iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
e66af07ca2
linux/drivers/tty/serial/sh-sci.c
Jiri Slaby 3f8bab174c serial: make uart_console_write->putchar()'s character an unsigned char 
Currently, uart_console_write->putchar's second parameter (the
character) is of type int. It makes little sense, provided uart_console_write()
accepts the input string as "const char *s" and passes its content -- the
characters -- to putchar(). So switch the character's type to unsigned
char.

We don't use char as that is signed on some platforms. That would cause
troubles for drivers which (implicitly) cast the char to u16 when
writing to the device. Sign extension would happen in that case and the
value written would be completely different to the provided char. DZ is
an example of such a driver -- on MIPS, it uses u16 for dz_out in
dz_console_putchar().

Note we do the char -> uchar conversion implicitly in
uart_console_write(). Provided we do not change size of the data type,
sign extension does not happen there, so the problem is void.

This makes the types consistent and unified with the rest of the uart
layer, which uses unsigned char in most places already. One exception is
xmit_buf, but that is going to be converted later.

Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Karol Gugala <kgugala@antmicro.com>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Takao Orito <orito.takao@socionext.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <peter@korsgaard.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com> [atmel_serial]
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Neil Armstrong <narmstrong@baylibre.com> # meson_serial
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220303080831.21783-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-03 15:06:31 +01:00

3489 lines
84 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
/*
* SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
*
* Copyright (C) 2002 - 2011 Paul Mundt
* Copyright (C) 2015 Glider bvba
* Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
*
* based off of the old drivers/char/sh-sci.c by:
*
* Copyright (C) 1999, 2000 Niibe Yutaka
* Copyright (C) 2000 Sugioka Toshinobu
* Modified to support multiple serial ports. Stuart Menefy (May 2000).
* Modified to support SecureEdge. David McCullough (2002)
* Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
* Removed SH7300 support (Jul 2007).
*/
#undef DEBUG
#include <linux/clk.h>
#include <linux/console.h>
#include <linux/ctype.h>
#include <linux/cpufreq.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/ktime.h>
#include <linux/major.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/scatterlist.h>
#include <linux/serial.h>
#include <linux/serial_sci.h>
#include <linux/sh_dma.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/sysrq.h>
#include <linux/timer.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#ifdef CONFIG_SUPERH
#include <asm/sh_bios.h>
#include <asm/platform_early.h>
#endif
#include "serial_mctrl_gpio.h"
#include "sh-sci.h"
/* Offsets into the sci_port->irqs array */
enum {
SCIx_ERI_IRQ,
SCIx_RXI_IRQ,
SCIx_TXI_IRQ,
SCIx_BRI_IRQ,
SCIx_DRI_IRQ,
SCIx_TEI_IRQ,
SCIx_NR_IRQS,
SCIx_MUX_IRQ = SCIx_NR_IRQS, /* special case */
};
#define SCIx_IRQ_IS_MUXED(port) \
((port)->irqs[SCIx_ERI_IRQ] == \
(port)->irqs[SCIx_RXI_IRQ]) || \
((port)->irqs[SCIx_ERI_IRQ] && \
((port)->irqs[SCIx_RXI_IRQ] < 0))
enum SCI_CLKS {
SCI_FCK, /* Functional Clock */
SCI_SCK, /* Optional External Clock */
SCI_BRG_INT, /* Optional BRG Internal Clock Source */
SCI_SCIF_CLK, /* Optional BRG External Clock Source */
SCI_NUM_CLKS
};
/* Bit x set means sampling rate x + 1 is supported */
#define SCI_SR(x) BIT((x) - 1)
#define SCI_SR_RANGE(x, y) GENMASK((y) - 1, (x) - 1)
#define SCI_SR_SCIFAB SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
SCI_SR(19) | SCI_SR(27)
#define min_sr(_port) ffs((_port)->sampling_rate_mask)
#define max_sr(_port) fls((_port)->sampling_rate_mask)
/* Iterate over all supported sampling rates, from high to low */
#define for_each_sr(_sr, _port) \
for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--) \
if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
struct plat_sci_reg {
u8 offset, size;
};
struct sci_port_params {
const struct plat_sci_reg regs[SCIx_NR_REGS];
unsigned int fifosize;
unsigned int overrun_reg;
unsigned int overrun_mask;
unsigned int sampling_rate_mask;
unsigned int error_mask;
unsigned int error_clear;
};
struct sci_port {
struct uart_port port;
/* Platform configuration */
const struct sci_port_params *params;
const struct plat_sci_port *cfg;
unsigned int sampling_rate_mask;
resource_size_t reg_size;
struct mctrl_gpios *gpios;
/* Clocks */
struct clk *clks[SCI_NUM_CLKS];
unsigned long clk_rates[SCI_NUM_CLKS];
int irqs[SCIx_NR_IRQS];
char *irqstr[SCIx_NR_IRQS];
struct dma_chan *chan_tx;
struct dma_chan *chan_rx;
#ifdef CONFIG_SERIAL_SH_SCI_DMA
struct dma_chan *chan_tx_saved;
struct dma_chan *chan_rx_saved;
dma_cookie_t cookie_tx;
dma_cookie_t cookie_rx[2];
dma_cookie_t active_rx;
dma_addr_t tx_dma_addr;
unsigned int tx_dma_len;
struct scatterlist sg_rx[2];
void *rx_buf[2];
size_t buf_len_rx;
struct work_struct work_tx;
struct hrtimer rx_timer;
unsigned int rx_timeout; /* microseconds */
#endif
unsigned int rx_frame;
int rx_trigger;
struct timer_list rx_fifo_timer;
int rx_fifo_timeout;
u16 hscif_tot;
bool has_rtscts;
bool autorts;
};
#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
static struct sci_port sci_ports[SCI_NPORTS];
static unsigned long sci_ports_in_use;
static struct uart_driver sci_uart_driver;
static inline struct sci_port *
to_sci_port(struct uart_port *uart)
{
return container_of(uart, struct sci_port, port);
}
static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
/*
* Common SCI definitions, dependent on the port's regshift
* value.
*/
[SCIx_SCI_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 8 },
[SCBRR] = { 0x01, 8 },
[SCSCR] = { 0x02, 8 },
[SCxTDR] = { 0x03, 8 },
[SCxSR] = { 0x04, 8 },
[SCxRDR] = { 0x05, 8 },
},
.fifosize = 1,
.overrun_reg = SCxSR,
.overrun_mask = SCI_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
},
/*
* Common definitions for legacy IrDA ports.
*/
[SCIx_IRDA_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 8 },
[SCBRR] = { 0x02, 8 },
[SCSCR] = { 0x04, 8 },
[SCxTDR] = { 0x06, 8 },
[SCxSR] = { 0x08, 16 },
[SCxRDR] = { 0x0a, 8 },
[SCFCR] = { 0x0c, 8 },
[SCFDR] = { 0x0e, 16 },
},
.fifosize = 1,
.overrun_reg = SCxSR,
.overrun_mask = SCI_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
},
/*
* Common SCIFA definitions.
*/
[SCIx_SCIFA_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x20, 8 },
[SCxSR] = { 0x14, 16 },
[SCxRDR] = { 0x24, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
[SCPCR] = { 0x30, 16 },
[SCPDR] = { 0x34, 16 },
},
.fifosize = 64,
.overrun_reg = SCxSR,
.overrun_mask = SCIFA_ORER,
.sampling_rate_mask = SCI_SR_SCIFAB,
.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
},
/*
* Common SCIFB definitions.
*/
[SCIx_SCIFB_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x40, 8 },
[SCxSR] = { 0x14, 16 },
[SCxRDR] = { 0x60, 8 },
[SCFCR] = { 0x18, 16 },
[SCTFDR] = { 0x38, 16 },
[SCRFDR] = { 0x3c, 16 },
[SCPCR] = { 0x30, 16 },
[SCPDR] = { 0x34, 16 },
},
.fifosize = 256,
.overrun_reg = SCxSR,
.overrun_mask = SCIFA_ORER,
.sampling_rate_mask = SCI_SR_SCIFAB,
.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
},
/*
* Common SH-2(A) SCIF definitions for ports with FIFO data
* count registers.
*/
[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x0c, 8 },
[SCxSR] = { 0x10, 16 },
[SCxRDR] = { 0x14, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
[SCSPTR] = { 0x20, 16 },
[SCLSR] = { 0x24, 16 },
},
.fifosize = 16,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* The "SCIFA" that is in RZ/A2, RZ/G2L and RZ/T.
* It looks like a normal SCIF with FIFO data, but with a
* compressed address space. Also, the break out of interrupts
* are different: ERI/BRI, RXI, TXI, TEI, DRI.
*/
[SCIx_RZ_SCIFA_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x02, 8 },
[SCSCR] = { 0x04, 16 },
[SCxTDR] = { 0x06, 8 },
[SCxSR] = { 0x08, 16 },
[SCxRDR] = { 0x0A, 8 },
[SCFCR] = { 0x0C, 16 },
[SCFDR] = { 0x0E, 16 },
[SCSPTR] = { 0x10, 16 },
[SCLSR] = { 0x12, 16 },
[SEMR] = { 0x14, 8 },
},
.fifosize = 16,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* Common SH-3 SCIF definitions.
*/
[SCIx_SH3_SCIF_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 8 },
[SCBRR] = { 0x02, 8 },
[SCSCR] = { 0x04, 8 },
[SCxTDR] = { 0x06, 8 },
[SCxSR] = { 0x08, 16 },
[SCxRDR] = { 0x0a, 8 },
[SCFCR] = { 0x0c, 8 },
[SCFDR] = { 0x0e, 16 },
},
.fifosize = 16,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* Common SH-4(A) SCIF(B) definitions.
*/
[SCIx_SH4_SCIF_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x0c, 8 },
[SCxSR] = { 0x10, 16 },
[SCxRDR] = { 0x14, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
[SCSPTR] = { 0x20, 16 },
[SCLSR] = { 0x24, 16 },
},
.fifosize = 16,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* Common SCIF definitions for ports with a Baud Rate Generator for
* External Clock (BRG).
*/
[SCIx_SH4_SCIF_BRG_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x0c, 8 },
[SCxSR] = { 0x10, 16 },
[SCxRDR] = { 0x14, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
[SCSPTR] = { 0x20, 16 },
[SCLSR] = { 0x24, 16 },
[SCDL] = { 0x30, 16 },
[SCCKS] = { 0x34, 16 },
},
.fifosize = 16,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* Common HSCIF definitions.
*/
[SCIx_HSCIF_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x0c, 8 },
[SCxSR] = { 0x10, 16 },
[SCxRDR] = { 0x14, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
[SCSPTR] = { 0x20, 16 },
[SCLSR] = { 0x24, 16 },
[HSSRR] = { 0x40, 16 },
[SCDL] = { 0x30, 16 },
[SCCKS] = { 0x34, 16 },
[HSRTRGR] = { 0x54, 16 },
[HSTTRGR] = { 0x58, 16 },
},
.fifosize = 128,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR_RANGE(8, 32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
* register.
*/
[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x0c, 8 },
[SCxSR] = { 0x10, 16 },
[SCxRDR] = { 0x14, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
[SCLSR] = { 0x24, 16 },
},
.fifosize = 16,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* Common SH-4(A) SCIF(B) definitions for ports with FIFO data
* count registers.
*/
[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x0c, 8 },
[SCxSR] = { 0x10, 16 },
[SCxRDR] = { 0x14, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
[SCTFDR] = { 0x1c, 16 }, /* aliased to SCFDR */
[SCRFDR] = { 0x20, 16 },
[SCSPTR] = { 0x24, 16 },
[SCLSR] = { 0x28, 16 },
},
.fifosize = 16,
.overrun_reg = SCLSR,
.overrun_mask = SCLSR_ORER,
.sampling_rate_mask = SCI_SR(32),
.error_mask = SCIF_DEFAULT_ERROR_MASK,
.error_clear = SCIF_ERROR_CLEAR,
},
/*
* SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
* registers.
*/
[SCIx_SH7705_SCIF_REGTYPE] = {
.regs = {
[SCSMR] = { 0x00, 16 },
[SCBRR] = { 0x04, 8 },
[SCSCR] = { 0x08, 16 },
[SCxTDR] = { 0x20, 8 },
[SCxSR] = { 0x14, 16 },
[SCxRDR] = { 0x24, 8 },
[SCFCR] = { 0x18, 16 },
[SCFDR] = { 0x1c, 16 },
},
.fifosize = 64,
.overrun_reg = SCxSR,
.overrun_mask = SCIFA_ORER,
.sampling_rate_mask = SCI_SR(16),
.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
},
};
#define sci_getreg(up, offset) (&to_sci_port(up)->params->regs[offset])
/*
* The "offset" here is rather misleading, in that it refers to an enum
* value relative to the port mapping rather than the fixed offset
* itself, which needs to be manually retrieved from the platform's
* register map for the given port.
*/
static unsigned int sci_serial_in(struct uart_port *p, int offset)
{
const struct plat_sci_reg *reg = sci_getreg(p, offset);
if (reg->size == 8)
return ioread8(p->membase + (reg->offset << p->regshift));
else if (reg->size == 16)
return ioread16(p->membase + (reg->offset << p->regshift));
else
WARN(1, "Invalid register access\n");
return 0;
}
static void sci_serial_out(struct uart_port *p, int offset, int value)
{
const struct plat_sci_reg *reg = sci_getreg(p, offset);
if (reg->size == 8)
iowrite8(value, p->membase + (reg->offset << p->regshift));
else if (reg->size == 16)
iowrite16(value, p->membase + (reg->offset << p->regshift));
else
WARN(1, "Invalid register access\n");
}
static void sci_port_enable(struct sci_port *sci_port)
{
unsigned int i;
if (!sci_port->port.dev)
return;
pm_runtime_get_sync(sci_port->port.dev);
for (i = 0; i < SCI_NUM_CLKS; i++) {
clk_prepare_enable(sci_port->clks[i]);
sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
}
sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
}
static void sci_port_disable(struct sci_port *sci_port)
{
unsigned int i;
if (!sci_port->port.dev)
return;
for (i = SCI_NUM_CLKS; i-- > 0; )
clk_disable_unprepare(sci_port->clks[i]);
pm_runtime_put_sync(sci_port->port.dev);
}
static inline unsigned long port_rx_irq_mask(struct uart_port *port)
{
/*
* Not all ports (such as SCIFA) will support REIE. Rather than
* special-casing the port type, we check the port initialization
* IRQ enable mask to see whether the IRQ is desired at all. If
* it's unset, it's logically inferred that there's no point in
* testing for it.
*/
return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
}
static void sci_start_tx(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
unsigned short ctrl;
#ifdef CONFIG_SERIAL_SH_SCI_DMA
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
u16 new, scr = serial_port_in(port, SCSCR);
if (s->chan_tx)
new = scr | SCSCR_TDRQE;
else
new = scr & ~SCSCR_TDRQE;
if (new != scr)
serial_port_out(port, SCSCR, new);
}
if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
dma_submit_error(s->cookie_tx)) {
s->cookie_tx = 0;
schedule_work(&s->work_tx);
}
#endif
if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
ctrl = serial_port_in(port, SCSCR);
serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
}
}
static void sci_stop_tx(struct uart_port *port)
{
unsigned short ctrl;
/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
ctrl = serial_port_in(port, SCSCR);
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
ctrl &= ~SCSCR_TDRQE;
ctrl &= ~SCSCR_TIE;
serial_port_out(port, SCSCR, ctrl);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
if (to_sci_port(port)->chan_tx &&
!dma_submit_error(to_sci_port(port)->cookie_tx)) {
dmaengine_terminate_async(to_sci_port(port)->chan_tx);
to_sci_port(port)->cookie_tx = -EINVAL;
}
#endif
}
static void sci_start_rx(struct uart_port *port)
{
unsigned short ctrl;
ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
ctrl &= ~SCSCR_RDRQE;
serial_port_out(port, SCSCR, ctrl);
}
static void sci_stop_rx(struct uart_port *port)
{
unsigned short ctrl;
ctrl = serial_port_in(port, SCSCR);
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
ctrl &= ~SCSCR_RDRQE;
ctrl &= ~port_rx_irq_mask(port);
serial_port_out(port, SCSCR, ctrl);
}
static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
{
if (port->type == PORT_SCI) {
/* Just store the mask */
serial_port_out(port, SCxSR, mask);
} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
/* Only clear the status bits we want to clear */
serial_port_out(port, SCxSR,
serial_port_in(port, SCxSR) & mask);
} else {
/* Store the mask, clear parity/framing errors */
serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
}
}
#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
#ifdef CONFIG_CONSOLE_POLL
static int sci_poll_get_char(struct uart_port *port)
{
unsigned short status;
int c;
do {
status = serial_port_in(port, SCxSR);
if (status & SCxSR_ERRORS(port)) {
sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
continue;
}
break;
} while (1);
if (!(status & SCxSR_RDxF(port)))
return NO_POLL_CHAR;
c = serial_port_in(port, SCxRDR);
/* Dummy read */
serial_port_in(port, SCxSR);
sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
return c;
}
#endif
static void sci_poll_put_char(struct uart_port *port, unsigned char c)
{
unsigned short status;
do {
status = serial_port_in(port, SCxSR);
} while (!(status & SCxSR_TDxE(port)));
serial_port_out(port, SCxTDR, c);
sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
}
#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
CONFIG_SERIAL_SH_SCI_EARLYCON */
static void sci_init_pins(struct uart_port *port, unsigned int cflag)
{
struct sci_port *s = to_sci_port(port);
/*
* Use port-specific handler if provided.
*/
if (s->cfg->ops && s->cfg->ops->init_pins) {
s->cfg->ops->init_pins(port, cflag);
return;
}
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
u16 data = serial_port_in(port, SCPDR);
u16 ctrl = serial_port_in(port, SCPCR);
/* Enable RXD and TXD pin functions */
ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
if (to_sci_port(port)->has_rtscts) {
/* RTS# is output, active low, unless autorts */
if (!(port->mctrl & TIOCM_RTS)) {
ctrl |= SCPCR_RTSC;
data |= SCPDR_RTSD;
} else if (!s->autorts) {
ctrl |= SCPCR_RTSC;
data &= ~SCPDR_RTSD;
} else {
/* Enable RTS# pin function */
ctrl &= ~SCPCR_RTSC;
}
/* Enable CTS# pin function */
ctrl &= ~SCPCR_CTSC;
}
serial_port_out(port, SCPDR, data);
serial_port_out(port, SCPCR, ctrl);
} else if (sci_getreg(port, SCSPTR)->size) {
u16 status = serial_port_in(port, SCSPTR);
/* RTS# is always output; and active low, unless autorts */
status |= SCSPTR_RTSIO;
if (!(port->mctrl & TIOCM_RTS))
status |= SCSPTR_RTSDT;
else if (!s->autorts)
status &= ~SCSPTR_RTSDT;
/* CTS# and SCK are inputs */
status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
serial_port_out(port, SCSPTR, status);
}
}
static int sci_txfill(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
const struct plat_sci_reg *reg;
reg = sci_getreg(port, SCTFDR);
if (reg->size)
return serial_port_in(port, SCTFDR) & fifo_mask;
reg = sci_getreg(port, SCFDR);
if (reg->size)
return serial_port_in(port, SCFDR) >> 8;
return !(serial_port_in(port, SCxSR) & SCI_TDRE);
}
static int sci_txroom(struct uart_port *port)
{
return port->fifosize - sci_txfill(port);
}
static int sci_rxfill(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
const struct plat_sci_reg *reg;
reg = sci_getreg(port, SCRFDR);
if (reg->size)
return serial_port_in(port, SCRFDR) & fifo_mask;
reg = sci_getreg(port, SCFDR);
if (reg->size)
return serial_port_in(port, SCFDR) & fifo_mask;
return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
}
/* ********************************************************************** *
* the interrupt related routines *
* ********************************************************************** */
static void sci_transmit_chars(struct uart_port *port)
{
struct circ_buf *xmit = &port->state->xmit;
unsigned int stopped = uart_tx_stopped(port);
unsigned short status;
unsigned short ctrl;
int count;
status = serial_port_in(port, SCxSR);
if (!(status & SCxSR_TDxE(port))) {
ctrl = serial_port_in(port, SCSCR);
if (uart_circ_empty(xmit))
ctrl &= ~SCSCR_TIE;
else
ctrl |= SCSCR_TIE;
serial_port_out(port, SCSCR, ctrl);
return;
}
count = sci_txroom(port);
do {
unsigned char c;
if (port->x_char) {
c = port->x_char;
port->x_char = 0;
} else if (!uart_circ_empty(xmit) && !stopped) {
c = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
} else {
break;
}
serial_port_out(port, SCxTDR, c);
port->icount.tx++;
} while (--count > 0);
sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (uart_circ_empty(xmit))
sci_stop_tx(port);
}
static void sci_receive_chars(struct uart_port *port)
{
struct tty_port *tport = &port->state->port;
int i, count, copied = 0;
unsigned short status;
unsigned char flag;
status = serial_port_in(port, SCxSR);
if (!(status & SCxSR_RDxF(port)))
return;
while (1) {
/* Don't copy more bytes than there is room for in the buffer */
count = tty_buffer_request_room(tport, sci_rxfill(port));
/* If for any reason we can't copy more data, we're done! */
if (count == 0)
break;
if (port->type == PORT_SCI) {
char c = serial_port_in(port, SCxRDR);
if (uart_handle_sysrq_char(port, c))
count = 0;
else
tty_insert_flip_char(tport, c, TTY_NORMAL);
} else {
for (i = 0; i < count; i++) {
char c;
if (port->type == PORT_SCIF ||
port->type == PORT_HSCIF) {
status = serial_port_in(port, SCxSR);
c = serial_port_in(port, SCxRDR);
} else {
c = serial_port_in(port, SCxRDR);
status = serial_port_in(port, SCxSR);
}
if (uart_handle_sysrq_char(port, c)) {
count--; i--;
continue;
}
/* Store data and status */
if (status & SCxSR_FER(port)) {
flag = TTY_FRAME;
port->icount.frame++;
} else if (status & SCxSR_PER(port)) {
flag = TTY_PARITY;
port->icount.parity++;
} else
flag = TTY_NORMAL;
tty_insert_flip_char(tport, c, flag);
}
}
serial_port_in(port, SCxSR); /* dummy read */
sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
copied += count;
port->icount.rx += count;
}
if (copied) {
/* Tell the rest of the system the news. New characters! */
tty_flip_buffer_push(tport);
} else {
/* TTY buffers full; read from RX reg to prevent lockup */
serial_port_in(port, SCxRDR);
serial_port_in(port, SCxSR); /* dummy read */
sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
}
}
static int sci_handle_errors(struct uart_port *port)
{
int copied = 0;
unsigned short status = serial_port_in(port, SCxSR);
struct tty_port *tport = &port->state->port;
struct sci_port *s = to_sci_port(port);
/* Handle overruns */
if (status & s->params->overrun_mask) {
port->icount.overrun++;
/* overrun error */
if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
copied++;
}
if (status & SCxSR_FER(port)) {
/* frame error */
port->icount.frame++;
if (tty_insert_flip_char(tport, 0, TTY_FRAME))
copied++;
}
if (status & SCxSR_PER(port)) {
/* parity error */
port->icount.parity++;
if (tty_insert_flip_char(tport, 0, TTY_PARITY))
copied++;
}
if (copied)
tty_flip_buffer_push(tport);
return copied;
}
static int sci_handle_fifo_overrun(struct uart_port *port)
{
struct tty_port *tport = &port->state->port;
struct sci_port *s = to_sci_port(port);
const struct plat_sci_reg *reg;
int copied = 0;
u16 status;
reg = sci_getreg(port, s->params->overrun_reg);
if (!reg->size)
return 0;
status = serial_port_in(port, s->params->overrun_reg);
if (status & s->params->overrun_mask) {
status &= ~s->params->overrun_mask;
serial_port_out(port, s->params->overrun_reg, status);
port->icount.overrun++;
tty_insert_flip_char(tport, 0, TTY_OVERRUN);
tty_flip_buffer_push(tport);
copied++;
}
return copied;
}
static int sci_handle_breaks(struct uart_port *port)
{
int copied = 0;
unsigned short status = serial_port_in(port, SCxSR);
struct tty_port *tport = &port->state->port;
if (uart_handle_break(port))
return 0;
if (status & SCxSR_BRK(port)) {
port->icount.brk++;
/* Notify of BREAK */
if (tty_insert_flip_char(tport, 0, TTY_BREAK))
copied++;
}
if (copied)
tty_flip_buffer_push(tport);
copied += sci_handle_fifo_overrun(port);
return copied;
}
static int scif_set_rtrg(struct uart_port *port, int rx_trig)
{
unsigned int bits;
if (rx_trig >= port->fifosize)
rx_trig = port->fifosize - 1;
if (rx_trig < 1)
rx_trig = 1;
/* HSCIF can be set to an arbitrary level. */
if (sci_getreg(port, HSRTRGR)->size) {
serial_port_out(port, HSRTRGR, rx_trig);
return rx_trig;
}
switch (port->type) {
case PORT_SCIF:
if (rx_trig < 4) {
bits = 0;
rx_trig = 1;
} else if (rx_trig < 8) {
bits = SCFCR_RTRG0;
rx_trig = 4;
} else if (rx_trig < 14) {
bits = SCFCR_RTRG1;
rx_trig = 8;
} else {
bits = SCFCR_RTRG0 | SCFCR_RTRG1;
rx_trig = 14;
}
break;
case PORT_SCIFA:
case PORT_SCIFB:
if (rx_trig < 16) {
bits = 0;
rx_trig = 1;
} else if (rx_trig < 32) {
bits = SCFCR_RTRG0;
rx_trig = 16;
} else if (rx_trig < 48) {
bits = SCFCR_RTRG1;
rx_trig = 32;
} else {
bits = SCFCR_RTRG0 | SCFCR_RTRG1;
rx_trig = 48;
}
break;
default:
WARN(1, "unknown FIFO configuration");
return 1;
}
serial_port_out(port, SCFCR,
(serial_port_in(port, SCFCR) &
~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
return rx_trig;
}
static int scif_rtrg_enabled(struct uart_port *port)
{
if (sci_getreg(port, HSRTRGR)->size)
return serial_port_in(port, HSRTRGR) != 0;
else
return (serial_port_in(port, SCFCR) &
(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
}
static void rx_fifo_timer_fn(struct timer_list *t)
{
struct sci_port *s = from_timer(s, t, rx_fifo_timer);
struct uart_port *port = &s->port;
dev_dbg(port->dev, "Rx timed out\n");
scif_set_rtrg(port, 1);
}
static ssize_t rx_fifo_trigger_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uart_port *port = dev_get_drvdata(dev);
struct sci_port *sci = to_sci_port(port);
return sprintf(buf, "%d\n", sci->rx_trigger);
}
static ssize_t rx_fifo_trigger_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct uart_port *port = dev_get_drvdata(dev);
struct sci_port *sci = to_sci_port(port);
int ret;
long r;
ret = kstrtol(buf, 0, &r);
if (ret)
return ret;
sci->rx_trigger = scif_set_rtrg(port, r);
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
scif_set_rtrg(port, 1);
return count;
}
static DEVICE_ATTR_RW(rx_fifo_trigger);
static ssize_t rx_fifo_timeout_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct uart_port *port = dev_get_drvdata(dev);
struct sci_port *sci = to_sci_port(port);
int v;
if (port->type == PORT_HSCIF)
v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
else
v = sci->rx_fifo_timeout;
return sprintf(buf, "%d\n", v);
}
static ssize_t rx_fifo_timeout_store(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t count)
{
struct uart_port *port = dev_get_drvdata(dev);
struct sci_port *sci = to_sci_port(port);
int ret;
long r;
ret = kstrtol(buf, 0, &r);
if (ret)
return ret;
if (port->type == PORT_HSCIF) {
if (r < 0 || r > 3)
return -EINVAL;
sci->hscif_tot = r << HSSCR_TOT_SHIFT;
} else {
sci->rx_fifo_timeout = r;
scif_set_rtrg(port, 1);
if (r > 0)
timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
}
return count;
}
static DEVICE_ATTR_RW(rx_fifo_timeout);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
static void sci_dma_tx_complete(void *arg)
{
struct sci_port *s = arg;
struct uart_port *port = &s->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long flags;
dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
spin_lock_irqsave(&port->lock, flags);
xmit->tail += s->tx_dma_len;
xmit->tail &= UART_XMIT_SIZE - 1;
port->icount.tx += s->tx_dma_len;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (!uart_circ_empty(xmit)) {
s->cookie_tx = 0;
schedule_work(&s->work_tx);
} else {
s->cookie_tx = -EINVAL;
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
u16 ctrl = serial_port_in(port, SCSCR);
serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
}
}
spin_unlock_irqrestore(&port->lock, flags);
}
/* Locking: called with port lock held */
static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
{
struct uart_port *port = &s->port;
struct tty_port *tport = &port->state->port;
int copied;
copied = tty_insert_flip_string(tport, buf, count);
if (copied < count)
port->icount.buf_overrun++;
port->icount.rx += copied;
return copied;
}
static int sci_dma_rx_find_active(struct sci_port *s)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
if (s->active_rx == s->cookie_rx[i])
return i;
return -1;
}
static void sci_dma_rx_chan_invalidate(struct sci_port *s)
{
unsigned int i;
s->chan_rx = NULL;
for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
s->cookie_rx[i] = -EINVAL;
s->active_rx = 0;
}
static void sci_dma_rx_release(struct sci_port *s)
{
struct dma_chan *chan = s->chan_rx_saved;
s->chan_rx_saved = NULL;
sci_dma_rx_chan_invalidate(s);
dmaengine_terminate_sync(chan);
dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
sg_dma_address(&s->sg_rx[0]));
dma_release_channel(chan);
}
static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
{
long sec = usec / 1000000;
long nsec = (usec % 1000000) * 1000;
ktime_t t = ktime_set(sec, nsec);
hrtimer_start(hrt, t, HRTIMER_MODE_REL);
}
static void sci_dma_rx_reenable_irq(struct sci_port *s)
{
struct uart_port *port = &s->port;
u16 scr;
/* Direct new serial port interrupts back to CPU */
scr = serial_port_in(port, SCSCR);
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
scr &= ~SCSCR_RDRQE;
enable_irq(s->irqs[SCIx_RXI_IRQ]);
}
serial_port_out(port, SCSCR, scr | SCSCR_RIE);
}
static void sci_dma_rx_complete(void *arg)
{
struct sci_port *s = arg;
struct dma_chan *chan = s->chan_rx;
struct uart_port *port = &s->port;
struct dma_async_tx_descriptor *desc;
unsigned long flags;
int active, count = 0;
dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
s->active_rx);
spin_lock_irqsave(&port->lock, flags);
active = sci_dma_rx_find_active(s);
if (active >= 0)
count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
start_hrtimer_us(&s->rx_timer, s->rx_timeout);
if (count)
tty_flip_buffer_push(&port->state->port);
desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc)
goto fail;
desc->callback = sci_dma_rx_complete;
desc->callback_param = s;
s->cookie_rx[active] = dmaengine_submit(desc);
if (dma_submit_error(s->cookie_rx[active]))
goto fail;
s->active_rx = s->cookie_rx[!active];
dma_async_issue_pending(chan);
spin_unlock_irqrestore(&port->lock, flags);
dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
__func__, s->cookie_rx[active], active, s->active_rx);
return;
fail:
spin_unlock_irqrestore(&port->lock, flags);
dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
/* Switch to PIO */
spin_lock_irqsave(&port->lock, flags);
dmaengine_terminate_async(chan);
sci_dma_rx_chan_invalidate(s);
sci_dma_rx_reenable_irq(s);
spin_unlock_irqrestore(&port->lock, flags);
}
static void sci_dma_tx_release(struct sci_port *s)
{
struct dma_chan *chan = s->chan_tx_saved;
cancel_work_sync(&s->work_tx);
s->chan_tx_saved = s->chan_tx = NULL;
s->cookie_tx = -EINVAL;
dmaengine_terminate_sync(chan);
dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
DMA_TO_DEVICE);
dma_release_channel(chan);
}
static int sci_dma_rx_submit(struct sci_port *s, bool port_lock_held)
{
struct dma_chan *chan = s->chan_rx;
struct uart_port *port = &s->port;
unsigned long flags;
int i;
for (i = 0; i < 2; i++) {
struct scatterlist *sg = &s->sg_rx[i];
struct dma_async_tx_descriptor *desc;
desc = dmaengine_prep_slave_sg(chan,
sg, 1, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc)
goto fail;
desc->callback = sci_dma_rx_complete;
desc->callback_param = s;
s->cookie_rx[i] = dmaengine_submit(desc);
if (dma_submit_error(s->cookie_rx[i]))
goto fail;
}
s->active_rx = s->cookie_rx[0];
dma_async_issue_pending(chan);
return 0;
fail:
/* Switch to PIO */
if (!port_lock_held)
spin_lock_irqsave(&port->lock, flags);
if (i)
dmaengine_terminate_async(chan);
sci_dma_rx_chan_invalidate(s);
sci_start_rx(port);
if (!port_lock_held)
spin_unlock_irqrestore(&port->lock, flags);
return -EAGAIN;
}
static void sci_dma_tx_work_fn(struct work_struct *work)
{
struct sci_port *s = container_of(work, struct sci_port, work_tx);
struct dma_async_tx_descriptor *desc;
struct dma_chan *chan = s->chan_tx;
struct uart_port *port = &s->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long flags;
dma_addr_t buf;
int head, tail;
/*
* DMA is idle now.
* Port xmit buffer is already mapped, and it is one page... Just adjust
* offsets and lengths. Since it is a circular buffer, we have to
* transmit till the end, and then the rest. Take the port lock to get a
* consistent xmit buffer state.
*/
spin_lock_irq(&port->lock);
head = xmit->head;
tail = xmit->tail;
buf = s->tx_dma_addr + (tail & (UART_XMIT_SIZE - 1));
s->tx_dma_len = min_t(unsigned int,
CIRC_CNT(head, tail, UART_XMIT_SIZE),
CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE));
if (!s->tx_dma_len) {
/* Transmit buffer has been flushed */
spin_unlock_irq(&port->lock);
return;
}
desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc) {
spin_unlock_irq(&port->lock);
dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
goto switch_to_pio;
}
dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
DMA_TO_DEVICE);
desc->callback = sci_dma_tx_complete;
desc->callback_param = s;
s->cookie_tx = dmaengine_submit(desc);
if (dma_submit_error(s->cookie_tx)) {
spin_unlock_irq(&port->lock);
dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
goto switch_to_pio;
}
spin_unlock_irq(&port->lock);
dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
__func__, xmit->buf, tail, head, s->cookie_tx);
dma_async_issue_pending(chan);
return;
switch_to_pio:
spin_lock_irqsave(&port->lock, flags);
s->chan_tx = NULL;
sci_start_tx(port);
spin_unlock_irqrestore(&port->lock, flags);
return;
}
static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
{
struct sci_port *s = container_of(t, struct sci_port, rx_timer);
struct dma_chan *chan = s->chan_rx;
struct uart_port *port = &s->port;
struct dma_tx_state state;
enum dma_status status;
unsigned long flags;
unsigned int read;
int active, count;
dev_dbg(port->dev, "DMA Rx timed out\n");
spin_lock_irqsave(&port->lock, flags);
active = sci_dma_rx_find_active(s);
if (active < 0) {
spin_unlock_irqrestore(&port->lock, flags);
return HRTIMER_NORESTART;
}
status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
if (status == DMA_COMPLETE) {
spin_unlock_irqrestore(&port->lock, flags);
dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
s->active_rx, active);
/* Let packet complete handler take care of the packet */
return HRTIMER_NORESTART;
}
dmaengine_pause(chan);
/*
* sometimes DMA transfer doesn't stop even if it is stopped and
* data keeps on coming until transaction is complete so check
* for DMA_COMPLETE again
* Let packet complete handler take care of the packet
*/
status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
if (status == DMA_COMPLETE) {
spin_unlock_irqrestore(&port->lock, flags);
dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
return HRTIMER_NORESTART;
}
/* Handle incomplete DMA receive */
dmaengine_terminate_async(s->chan_rx);
read = sg_dma_len(&s->sg_rx[active]) - state.residue;
if (read) {
count = sci_dma_rx_push(s, s->rx_buf[active], read);
if (count)
tty_flip_buffer_push(&port->state->port);
}
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
sci_dma_rx_submit(s, true);
sci_dma_rx_reenable_irq(s);
spin_unlock_irqrestore(&port->lock, flags);
return HRTIMER_NORESTART;
}
static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
enum dma_transfer_direction dir)
{
struct dma_chan *chan;
struct dma_slave_config cfg;
int ret;
chan = dma_request_slave_channel(port->dev,
dir == DMA_MEM_TO_DEV ? "tx" : "rx");
if (!chan) {
dev_dbg(port->dev, "dma_request_slave_channel failed\n");
return NULL;
}
memset(&cfg, 0, sizeof(cfg));
cfg.direction = dir;
if (dir == DMA_MEM_TO_DEV) {
cfg.dst_addr = port->mapbase +
(sci_getreg(port, SCxTDR)->offset << port->regshift);
cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
} else {
cfg.src_addr = port->mapbase +
(sci_getreg(port, SCxRDR)->offset << port->regshift);
cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
}
ret = dmaengine_slave_config(chan, &cfg);
if (ret) {
dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
dma_release_channel(chan);
return NULL;
}
return chan;
}
static void sci_request_dma(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
struct dma_chan *chan;
dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
/*
* DMA on console may interfere with Kernel log messages which use
* plain putchar(). So, simply don't use it with a console.
*/
if (uart_console(port))
return;
if (!port->dev->of_node)
return;
s->cookie_tx = -EINVAL;
/*
* Don't request a dma channel if no channel was specified
* in the device tree.
*/
if (!of_find_property(port->dev->of_node, "dmas", NULL))
return;
chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
if (chan) {
/* UART circular tx buffer is an aligned page. */
s->tx_dma_addr = dma_map_single(chan->device->dev,
port->state->xmit.buf,
UART_XMIT_SIZE,
DMA_TO_DEVICE);
if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
dma_release_channel(chan);
} else {
dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
__func__, UART_XMIT_SIZE,
port->state->xmit.buf, &s->tx_dma_addr);
INIT_WORK(&s->work_tx, sci_dma_tx_work_fn);
s->chan_tx_saved = s->chan_tx = chan;
}
}
chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
if (chan) {
unsigned int i;
dma_addr_t dma;
void *buf;
s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
&dma, GFP_KERNEL);
if (!buf) {
dev_warn(port->dev,
"Failed to allocate Rx dma buffer, using PIO\n");
dma_release_channel(chan);
return;
}
for (i = 0; i < 2; i++) {
struct scatterlist *sg = &s->sg_rx[i];
sg_init_table(sg, 1);
s->rx_buf[i] = buf;
sg_dma_address(sg) = dma;
sg_dma_len(sg) = s->buf_len_rx;
buf += s->buf_len_rx;
dma += s->buf_len_rx;
}
hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
s->rx_timer.function = sci_dma_rx_timer_fn;
s->chan_rx_saved = s->chan_rx = chan;
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
sci_dma_rx_submit(s, false);
}
}
static void sci_free_dma(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
if (s->chan_tx_saved)
sci_dma_tx_release(s);
if (s->chan_rx_saved)
sci_dma_rx_release(s);
}
static void sci_flush_buffer(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
/*
* In uart_flush_buffer(), the xmit circular buffer has just been
* cleared, so we have to reset tx_dma_len accordingly, and stop any
* pending transfers
*/
s->tx_dma_len = 0;
if (s->chan_tx) {
dmaengine_terminate_async(s->chan_tx);
s->cookie_tx = -EINVAL;
}
}
#else /* !CONFIG_SERIAL_SH_SCI_DMA */
static inline void sci_request_dma(struct uart_port *port)
{
}
static inline void sci_free_dma(struct uart_port *port)
{
}
#define sci_flush_buffer NULL
#endif /* !CONFIG_SERIAL_SH_SCI_DMA */
static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
{
struct uart_port *port = ptr;
struct sci_port *s = to_sci_port(port);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
if (s->chan_rx) {
u16 scr = serial_port_in(port, SCSCR);
u16 ssr = serial_port_in(port, SCxSR);
/* Disable future Rx interrupts */
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
disable_irq_nosync(irq);
scr |= SCSCR_RDRQE;
} else {
if (sci_dma_rx_submit(s, false) < 0)
goto handle_pio;
scr &= ~SCSCR_RIE;
}
serial_port_out(port, SCSCR, scr);
/* Clear current interrupt */
serial_port_out(port, SCxSR,
ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
jiffies, s->rx_timeout);
start_hrtimer_us(&s->rx_timer, s->rx_timeout);
return IRQ_HANDLED;
}
handle_pio:
#endif
if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
if (!scif_rtrg_enabled(port))
scif_set_rtrg(port, s->rx_trigger);
mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
}
/* I think sci_receive_chars has to be called irrespective
* of whether the I_IXOFF is set, otherwise, how is the interrupt
* to be disabled?
*/
sci_receive_chars(port);
return IRQ_HANDLED;
}
static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
{
struct uart_port *port = ptr;
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
sci_transmit_chars(port);
spin_unlock_irqrestore(&port->lock, flags);
return IRQ_HANDLED;
}
static irqreturn_t sci_br_interrupt(int irq, void *ptr)
{
struct uart_port *port = ptr;
/* Handle BREAKs */
sci_handle_breaks(port);
/* drop invalid character received before break was detected */
serial_port_in(port, SCxRDR);
sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
return IRQ_HANDLED;
}
static irqreturn_t sci_er_interrupt(int irq, void *ptr)
{
struct uart_port *port = ptr;
struct sci_port *s = to_sci_port(port);
if (s->irqs[SCIx_ERI_IRQ] == s->irqs[SCIx_BRI_IRQ]) {
/* Break and Error interrupts are muxed */
unsigned short ssr_status = serial_port_in(port, SCxSR);
/* Break Interrupt */
if (ssr_status & SCxSR_BRK(port))
sci_br_interrupt(irq, ptr);
/* Break only? */
if (!(ssr_status & SCxSR_ERRORS(port)))
return IRQ_HANDLED;
}
/* Handle errors */
if (port->type == PORT_SCI) {
if (sci_handle_errors(port)) {
/* discard character in rx buffer */
serial_port_in(port, SCxSR);
sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
}
} else {
sci_handle_fifo_overrun(port);
if (!s->chan_rx)
sci_receive_chars(port);
}
sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
/* Kick the transmission */
if (!s->chan_tx)
sci_tx_interrupt(irq, ptr);
return IRQ_HANDLED;
}
static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
{
unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
struct uart_port *port = ptr;
struct sci_port *s = to_sci_port(port);
irqreturn_t ret = IRQ_NONE;
ssr_status = serial_port_in(port, SCxSR);
scr_status = serial_port_in(port, SCSCR);
if (s->params->overrun_reg == SCxSR)
orer_status = ssr_status;
else if (sci_getreg(port, s->params->overrun_reg)->size)
orer_status = serial_port_in(port, s->params->overrun_reg);
err_enabled = scr_status & port_rx_irq_mask(port);
/* Tx Interrupt */
if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
!s->chan_tx)
ret = sci_tx_interrupt(irq, ptr);
/*
* Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
* DR flags
*/
if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
(scr_status & SCSCR_RIE))
ret = sci_rx_interrupt(irq, ptr);
/* Error Interrupt */
if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
ret = sci_er_interrupt(irq, ptr);
/* Break Interrupt */
if (s->irqs[SCIx_ERI_IRQ] != s->irqs[SCIx_BRI_IRQ] &&
(ssr_status & SCxSR_BRK(port)) && err_enabled)
ret = sci_br_interrupt(irq, ptr);
/* Overrun Interrupt */
if (orer_status & s->params->overrun_mask) {
sci_handle_fifo_overrun(port);
ret = IRQ_HANDLED;
}
return ret;
}
static const struct sci_irq_desc {
const char *desc;
irq_handler_t handler;
} sci_irq_desc[] = {
/*
* Split out handlers, the default case.
*/
[SCIx_ERI_IRQ] = {
.desc = "rx err",
.handler = sci_er_interrupt,
},
[SCIx_RXI_IRQ] = {
.desc = "rx full",
.handler = sci_rx_interrupt,
},
[SCIx_TXI_IRQ] = {
.desc = "tx empty",
.handler = sci_tx_interrupt,
},
[SCIx_BRI_IRQ] = {
.desc = "break",
.handler = sci_br_interrupt,
},
[SCIx_DRI_IRQ] = {
.desc = "rx ready",
.handler = sci_rx_interrupt,
},
[SCIx_TEI_IRQ] = {
.desc = "tx end",
.handler = sci_tx_interrupt,
},
/*
* Special muxed handler.
*/
[SCIx_MUX_IRQ] = {
.desc = "mux",
.handler = sci_mpxed_interrupt,
},
};
static int sci_request_irq(struct sci_port *port)
{
struct uart_port *up = &port->port;
int i, j, w, ret = 0;
for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
const struct sci_irq_desc *desc;
int irq;
/* Check if already registered (muxed) */
for (w = 0; w < i; w++)
if (port->irqs[w] == port->irqs[i])
w = i + 1;
if (w > i)
continue;
if (SCIx_IRQ_IS_MUXED(port)) {
i = SCIx_MUX_IRQ;
irq = up->irq;
} else {
irq = port->irqs[i];
/*
* Certain port types won't support all of the
* available interrupt sources.
*/
if (unlikely(irq < 0))
continue;
}
desc = sci_irq_desc + i;
port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
dev_name(up->dev), desc->desc);
if (!port->irqstr[j]) {
ret = -ENOMEM;
goto out_nomem;
}
ret = request_irq(irq, desc->handler, up->irqflags,
port->irqstr[j], port);
if (unlikely(ret)) {
dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
goto out_noirq;
}
}
return 0;
out_noirq:
while (--i >= 0)
free_irq(port->irqs[i], port);
out_nomem:
while (--j >= 0)
kfree(port->irqstr[j]);
return ret;
}
static void sci_free_irq(struct sci_port *port)
{
int i, j;
/*
* Intentionally in reverse order so we iterate over the muxed
* IRQ first.
*/
for (i = 0; i < SCIx_NR_IRQS; i++) {
int irq = port->irqs[i];
/*
* Certain port types won't support all of the available
* interrupt sources.
*/
if (unlikely(irq < 0))
continue;
/* Check if already freed (irq was muxed) */
for (j = 0; j < i; j++)
if (port->irqs[j] == irq)
j = i + 1;
if (j > i)
continue;
free_irq(port->irqs[i], port);
kfree(port->irqstr[i]);
if (SCIx_IRQ_IS_MUXED(port)) {
/* If there's only one IRQ, we're done. */
return;
}
}
}
static unsigned int sci_tx_empty(struct uart_port *port)
{
unsigned short status = serial_port_in(port, SCxSR);
unsigned short in_tx_fifo = sci_txfill(port);
return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
}
static void sci_set_rts(struct uart_port *port, bool state)
{
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
u16 data = serial_port_in(port, SCPDR);
/* Active low */
if (state)
data &= ~SCPDR_RTSD;
else
data |= SCPDR_RTSD;
serial_port_out(port, SCPDR, data);
/* RTS# is output */
serial_port_out(port, SCPCR,
serial_port_in(port, SCPCR) | SCPCR_RTSC);
} else if (sci_getreg(port, SCSPTR)->size) {
u16 ctrl = serial_port_in(port, SCSPTR);
/* Active low */
if (state)
ctrl &= ~SCSPTR_RTSDT;
else
ctrl |= SCSPTR_RTSDT;
serial_port_out(port, SCSPTR, ctrl);
}
}
static bool sci_get_cts(struct uart_port *port)
{
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
/* Active low */
return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
} else if (sci_getreg(port, SCSPTR)->size) {
/* Active low */
return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
}
return true;
}
/*
* Modem control is a bit of a mixed bag for SCI(F) ports. Generally
* CTS/RTS is supported in hardware by at least one port and controlled
* via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
* handled via the ->init_pins() op, which is a bit of a one-way street,
* lacking any ability to defer pin control -- this will later be
* converted over to the GPIO framework).
*
* Other modes (such as loopback) are supported generically on certain
* port types, but not others. For these it's sufficient to test for the
* existence of the support register and simply ignore the port type.
*/
static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct sci_port *s = to_sci_port(port);
if (mctrl & TIOCM_LOOP) {
const struct plat_sci_reg *reg;
/*
* Standard loopback mode for SCFCR ports.
*/
reg = sci_getreg(port, SCFCR);
if (reg->size)
serial_port_out(port, SCFCR,
serial_port_in(port, SCFCR) |
SCFCR_LOOP);
}
mctrl_gpio_set(s->gpios, mctrl);
if (!s->has_rtscts)
return;
if (!(mctrl & TIOCM_RTS)) {
/* Disable Auto RTS */
serial_port_out(port, SCFCR,
serial_port_in(port, SCFCR) & ~SCFCR_MCE);
/* Clear RTS */
sci_set_rts(port, 0);
} else if (s->autorts) {
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
/* Enable RTS# pin function */
serial_port_out(port, SCPCR,
serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
}
/* Enable Auto RTS */
serial_port_out(port, SCFCR,
serial_port_in(port, SCFCR) | SCFCR_MCE);
} else {
/* Set RTS */
sci_set_rts(port, 1);
}
}
static unsigned int sci_get_mctrl(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
struct mctrl_gpios *gpios = s->gpios;
unsigned int mctrl = 0;
mctrl_gpio_get(gpios, &mctrl);
/*
* CTS/RTS is handled in hardware when supported, while nothing
* else is wired up.
*/
if (s->autorts) {
if (sci_get_cts(port))
mctrl |= TIOCM_CTS;
} else if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS)) {
mctrl |= TIOCM_CTS;
}
if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR))
mctrl |= TIOCM_DSR;
if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD))
mctrl |= TIOCM_CAR;
return mctrl;
}
static void sci_enable_ms(struct uart_port *port)
{
mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
}
static void sci_break_ctl(struct uart_port *port, int break_state)
{
unsigned short scscr, scsptr;
unsigned long flags;
/* check whether the port has SCSPTR */
if (!sci_getreg(port, SCSPTR)->size) {
/*
* Not supported by hardware. Most parts couple break and rx
* interrupts together, with break detection always enabled.
*/
return;
}
spin_lock_irqsave(&port->lock, flags);
scsptr = serial_port_in(port, SCSPTR);
scscr = serial_port_in(port, SCSCR);
if (break_state == -1) {
scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
scscr &= ~SCSCR_TE;
} else {
scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
scscr |= SCSCR_TE;
}
serial_port_out(port, SCSPTR, scsptr);
serial_port_out(port, SCSCR, scscr);
spin_unlock_irqrestore(&port->lock, flags);
}
static int sci_startup(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
int ret;
dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
sci_request_dma(port);
ret = sci_request_irq(s);
if (unlikely(ret < 0)) {
sci_free_dma(port);
return ret;
}
return 0;
}
static void sci_shutdown(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
unsigned long flags;
u16 scr;
dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
s->autorts = false;
mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
spin_lock_irqsave(&port->lock, flags);
sci_stop_rx(port);
sci_stop_tx(port);
/*
* Stop RX and TX, disable related interrupts, keep clock source
* and HSCIF TOT bits
*/
scr = serial_port_in(port, SCSCR);
serial_port_out(port, SCSCR, scr &
(SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
spin_unlock_irqrestore(&port->lock, flags);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
if (s->chan_rx_saved) {
dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
port->line);
hrtimer_cancel(&s->rx_timer);
}
#endif
if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
del_timer_sync(&s->rx_fifo_timer);
sci_free_irq(s);
sci_free_dma(port);
}
static int sci_sck_calc(struct sci_port *s, unsigned int bps,
unsigned int *srr)
{
unsigned long freq = s->clk_rates[SCI_SCK];
int err, min_err = INT_MAX;
unsigned int sr;
if (s->port.type != PORT_HSCIF)
freq *= 2;
for_each_sr(sr, s) {
err = DIV_ROUND_CLOSEST(freq, sr) - bps;
if (abs(err) >= abs(min_err))
continue;
min_err = err;
*srr = sr - 1;
if (!err)
break;
}
dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
*srr + 1);
return min_err;
}
static int sci_brg_calc(struct sci_port *s, unsigned int bps,
unsigned long freq, unsigned int *dlr,
unsigned int *srr)
{
int err, min_err = INT_MAX;
unsigned int sr, dl;
if (s->port.type != PORT_HSCIF)
freq *= 2;
for_each_sr(sr, s) {
dl = DIV_ROUND_CLOSEST(freq, sr * bps);
dl = clamp(dl, 1U, 65535U);
err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
if (abs(err) >= abs(min_err))
continue;
min_err = err;
*dlr = dl;
*srr = sr - 1;
if (!err)
break;
}
dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
min_err, *dlr, *srr + 1);
return min_err;
}
/* calculate sample rate, BRR, and clock select */
static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
unsigned int *brr, unsigned int *srr,
unsigned int *cks)
{
unsigned long freq = s->clk_rates[SCI_FCK];
unsigned int sr, br, prediv, scrate, c;
int err, min_err = INT_MAX;
if (s->port.type != PORT_HSCIF)
freq *= 2;
/*
* Find the combination of sample rate and clock select with the
* smallest deviation from the desired baud rate.
* Prefer high sample rates to maximise the receive margin.
*
* M: Receive margin (%)
* N: Ratio of bit rate to clock (N = sampling rate)
* D: Clock duty (D = 0 to 1.0)
* L: Frame length (L = 9 to 12)
* F: Absolute value of clock frequency deviation
*
* M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
* (|D - 0.5| / N * (1 + F))|
* NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
*/
for_each_sr(sr, s) {
for (c = 0; c <= 3; c++) {
/* integerized formulas from HSCIF documentation */
prediv = sr << (2 * c + 1);
/*
* We need to calculate:
*
* br = freq / (prediv * bps) clamped to [1..256]
* err = freq / (br * prediv) - bps
*
* Watch out for overflow when calculating the desired
* sampling clock rate!
*/
if (bps > UINT_MAX / prediv)
break;
scrate = prediv * bps;
br = DIV_ROUND_CLOSEST(freq, scrate);
br = clamp(br, 1U, 256U);
err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
if (abs(err) >= abs(min_err))
continue;
min_err = err;
*brr = br - 1;
*srr = sr - 1;
*cks = c;
if (!err)
goto found;
}
}
found:
dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
min_err, *brr, *srr + 1, *cks);
return min_err;
}
static void sci_reset(struct uart_port *port)
{
const struct plat_sci_reg *reg;
unsigned int status;
struct sci_port *s = to_sci_port(port);
serial_port_out(port, SCSCR, s->hscif_tot); /* TE=0, RE=0, CKE1=0 */
reg = sci_getreg(port, SCFCR);
if (reg->size)
serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
sci_clear_SCxSR(port,
SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
SCxSR_BREAK_CLEAR(port));
if (sci_getreg(port, SCLSR)->size) {
status = serial_port_in(port, SCLSR);
status &= ~(SCLSR_TO | SCLSR_ORER);
serial_port_out(port, SCLSR, status);
}
if (s->rx_trigger > 1) {
if (s->rx_fifo_timeout) {
scif_set_rtrg(port, 1);
timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
} else {
if (port->type == PORT_SCIFA ||
port->type == PORT_SCIFB)
scif_set_rtrg(port, 1);
else
scif_set_rtrg(port, s->rx_trigger);
}
}
}
static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
struct sci_port *s = to_sci_port(port);
const struct plat_sci_reg *reg;
int min_err = INT_MAX, err;
unsigned long max_freq = 0;
int best_clk = -1;
unsigned long flags;
if ((termios->c_cflag & CSIZE) == CS7)
smr_val |= SCSMR_CHR;
if (termios->c_cflag & PARENB)
smr_val |= SCSMR_PE;
if (termios->c_cflag & PARODD)
smr_val |= SCSMR_PE | SCSMR_ODD;
if (termios->c_cflag & CSTOPB)
smr_val |= SCSMR_STOP;
/*
* earlyprintk comes here early on with port->uartclk set to zero.
* the clock framework is not up and running at this point so here
* we assume that 115200 is the maximum baud rate. please note that
* the baud rate is not programmed during earlyprintk - it is assumed
* that the previous boot loader has enabled required clocks and
* setup the baud rate generator hardware for us already.
*/
if (!port->uartclk) {
baud = uart_get_baud_rate(port, termios, old, 0, 115200);
goto done;
}
for (i = 0; i < SCI_NUM_CLKS; i++)
max_freq = max(max_freq, s->clk_rates[i]);
baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
if (!baud)
goto done;
/*
* There can be multiple sources for the sampling clock. Find the one
* that gives us the smallest deviation from the desired baud rate.
*/
/* Optional Undivided External Clock */
if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
port->type != PORT_SCIFB) {
err = sci_sck_calc(s, baud, &srr1);
if (abs(err) < abs(min_err)) {
best_clk = SCI_SCK;
scr_val = SCSCR_CKE1;
sccks = SCCKS_CKS;
min_err = err;
srr = srr1;
if (!err)
goto done;
}
}
/* Optional BRG Frequency Divided External Clock */
if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
&srr1);
if (abs(err) < abs(min_err)) {
best_clk = SCI_SCIF_CLK;
scr_val = SCSCR_CKE1;
sccks = 0;
min_err = err;
dl = dl1;
srr = srr1;
if (!err)
goto done;
}
}
/* Optional BRG Frequency Divided Internal Clock */
if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
&srr1);
if (abs(err) < abs(min_err)) {
best_clk = SCI_BRG_INT;
scr_val = SCSCR_CKE1;
sccks = SCCKS_XIN;
min_err = err;
dl = dl1;
srr = srr1;
if (!min_err)
goto done;
}
}
/* Divided Functional Clock using standard Bit Rate Register */
err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
if (abs(err) < abs(min_err)) {
best_clk = SCI_FCK;
scr_val = 0;
min_err = err;
brr = brr1;
srr = srr1;
cks = cks1;
}
done:
if (best_clk >= 0)
dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
s->clks[best_clk], baud, min_err);
sci_port_enable(s);
/*
* Program the optional External Baud Rate Generator (BRG) first.
* It controls the mux to select (H)SCK or frequency divided clock.
*/
if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
serial_port_out(port, SCDL, dl);
serial_port_out(port, SCCKS, sccks);
}
spin_lock_irqsave(&port->lock, flags);
sci_reset(port);
uart_update_timeout(port, termios->c_cflag, baud);
/* byte size and parity */
bits = tty_get_frame_size(termios->c_cflag);
if (sci_getreg(port, SEMR)->size)
serial_port_out(port, SEMR, 0);
if (best_clk >= 0) {
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
switch (srr + 1) {
case 5: smr_val |= SCSMR_SRC_5; break;
case 7: smr_val |= SCSMR_SRC_7; break;
case 11: smr_val |= SCSMR_SRC_11; break;
case 13: smr_val |= SCSMR_SRC_13; break;
case 16: smr_val |= SCSMR_SRC_16; break;
case 17: smr_val |= SCSMR_SRC_17; break;
case 19: smr_val |= SCSMR_SRC_19; break;
case 27: smr_val |= SCSMR_SRC_27; break;
}
smr_val |= cks;
serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
serial_port_out(port, SCSMR, smr_val);
serial_port_out(port, SCBRR, brr);
if (sci_getreg(port, HSSRR)->size) {
unsigned int hssrr = srr | HSCIF_SRE;
/* Calculate deviation from intended rate at the
* center of the last stop bit in sampling clocks.
*/
int last_stop = bits * 2 - 1;
int deviation = DIV_ROUND_CLOSEST(min_err * last_stop *
(int)(srr + 1),
2 * (int)baud);
if (abs(deviation) >= 2) {
/* At least two sampling clocks off at the
* last stop bit; we can increase the error
* margin by shifting the sampling point.
*/
int shift = clamp(deviation / 2, -8, 7);
hssrr |= (shift << HSCIF_SRHP_SHIFT) &
HSCIF_SRHP_MASK;
hssrr |= HSCIF_SRDE;
}
serial_port_out(port, HSSRR, hssrr);
}
/* Wait one bit interval */
udelay((1000000 + (baud - 1)) / baud);
} else {
/* Don't touch the bit rate configuration */
scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
smr_val |= serial_port_in(port, SCSMR) &
(SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
serial_port_out(port, SCSMR, smr_val);
}
sci_init_pins(port, termios->c_cflag);
port->status &= ~UPSTAT_AUTOCTS;
s->autorts = false;
reg = sci_getreg(port, SCFCR);
if (reg->size) {
unsigned short ctrl = serial_port_in(port, SCFCR);
if ((port->flags & UPF_HARD_FLOW) &&
(termios->c_cflag & CRTSCTS)) {
/* There is no CTS interrupt to restart the hardware */
port->status |= UPSTAT_AUTOCTS;
/* MCE is enabled when RTS is raised */
s->autorts = true;
}
/*
* As we've done a sci_reset() above, ensure we don't
* interfere with the FIFOs while toggling MCE. As the
* reset values could still be set, simply mask them out.
*/
ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
serial_port_out(port, SCFCR, ctrl);
}
if (port->flags & UPF_HARD_FLOW) {
/* Refresh (Auto) RTS */
sci_set_mctrl(port, port->mctrl);
}
scr_val |= SCSCR_RE | SCSCR_TE |
(s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
if ((srr + 1 == 5) &&
(port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
/*
* In asynchronous mode, when the sampling rate is 1/5, first
* received data may become invalid on some SCIFA and SCIFB.
* To avoid this problem wait more than 1 serial data time (1
* bit time x serial data number) after setting SCSCR.RE = 1.
*/
udelay(DIV_ROUND_UP(10 * 1000000, baud));
}
/* Calculate delay for 2 DMA buffers (4 FIFO). */
s->rx_frame = (10000 * bits) / (baud / 100);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
#endif
if ((termios->c_cflag & CREAD) != 0)
sci_start_rx(port);
spin_unlock_irqrestore(&port->lock, flags);
sci_port_disable(s);
if (UART_ENABLE_MS(port, termios->c_cflag))
sci_enable_ms(port);
}
static void sci_pm(struct uart_port *port, unsigned int state,
unsigned int oldstate)
{
struct sci_port *sci_port = to_sci_port(port);
switch (state) {
case UART_PM_STATE_OFF:
sci_port_disable(sci_port);
break;
default:
sci_port_enable(sci_port);
break;
}
}
static const char *sci_type(struct uart_port *port)
{
switch (port->type) {
case PORT_IRDA:
return "irda";
case PORT_SCI:
return "sci";
case PORT_SCIF:
return "scif";
case PORT_SCIFA:
return "scifa";
case PORT_SCIFB:
return "scifb";
case PORT_HSCIF:
return "hscif";
}
return NULL;
}
static int sci_remap_port(struct uart_port *port)
{
struct sci_port *sport = to_sci_port(port);
/*
* Nothing to do if there's already an established membase.
*/
if (port->membase)
return 0;
if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
port->membase = ioremap(port->mapbase, sport->reg_size);
if (unlikely(!port->membase)) {
dev_err(port->dev, "can't remap port#%d\n", port->line);
return -ENXIO;
}
} else {
/*
* For the simple (and majority of) cases where we don't
* need to do any remapping, just cast the cookie
* directly.
*/
port->membase = (void __iomem *)(uintptr_t)port->mapbase;
}
return 0;
}
static void sci_release_port(struct uart_port *port)
{
struct sci_port *sport = to_sci_port(port);
if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
iounmap(port->membase);
port->membase = NULL;
}
release_mem_region(port->mapbase, sport->reg_size);
}
static int sci_request_port(struct uart_port *port)
{
struct resource *res;
struct sci_port *sport = to_sci_port(port);
int ret;
res = request_mem_region(port->mapbase, sport->reg_size,
dev_name(port->dev));
if (unlikely(res == NULL)) {
dev_err(port->dev, "request_mem_region failed.");
return -EBUSY;
}
ret = sci_remap_port(port);
if (unlikely(ret != 0)) {
release_resource(res);
return ret;
}
return 0;
}
static void sci_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE) {
struct sci_port *sport = to_sci_port(port);
port->type = sport->cfg->type;
sci_request_port(port);
}
}
static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
{
if (ser->baud_base < 2400)
/* No paper tape reader for Mitch.. */
return -EINVAL;
return 0;
}
static const struct uart_ops sci_uart_ops = {
.tx_empty = sci_tx_empty,
.set_mctrl = sci_set_mctrl,
.get_mctrl = sci_get_mctrl,
.start_tx = sci_start_tx,
.stop_tx = sci_stop_tx,
.stop_rx = sci_stop_rx,
.enable_ms = sci_enable_ms,
.break_ctl = sci_break_ctl,
.startup = sci_startup,
.shutdown = sci_shutdown,
.flush_buffer = sci_flush_buffer,
.set_termios = sci_set_termios,
.pm = sci_pm,
.type = sci_type,
.release_port = sci_release_port,
.request_port = sci_request_port,
.config_port = sci_config_port,
.verify_port = sci_verify_port,
#ifdef CONFIG_CONSOLE_POLL
.poll_get_char = sci_poll_get_char,
.poll_put_char = sci_poll_put_char,
#endif
};
static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
{
const char *clk_names[] = {
[SCI_FCK] = "fck",
[SCI_SCK] = "sck",
[SCI_BRG_INT] = "brg_int",
[SCI_SCIF_CLK] = "scif_clk",
};
struct clk *clk;
unsigned int i;
if (sci_port->cfg->type == PORT_HSCIF)
clk_names[SCI_SCK] = "hsck";
for (i = 0; i < SCI_NUM_CLKS; i++) {
clk = devm_clk_get_optional(dev, clk_names[i]);
if (IS_ERR(clk))
return PTR_ERR(clk);
if (!clk && i == SCI_FCK) {
/*
* Not all SH platforms declare a clock lookup entry
* for SCI devices, in which case we need to get the
* global "peripheral_clk" clock.
*/
clk = devm_clk_get(dev, "peripheral_clk");
if (IS_ERR(clk))
return dev_err_probe(dev, PTR_ERR(clk),
"failed to get %s\n",
clk_names[i]);
}
if (!clk)
dev_dbg(dev, "failed to get %s\n", clk_names[i]);
else
dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
clk, clk_get_rate(clk));
sci_port->clks[i] = clk;
}
return 0;
}
static const struct sci_port_params *
sci_probe_regmap(const struct plat_sci_port *cfg)
{
unsigned int regtype;
if (cfg->regtype != SCIx_PROBE_REGTYPE)
return &sci_port_params[cfg->regtype];
switch (cfg->type) {
case PORT_SCI:
regtype = SCIx_SCI_REGTYPE;
break;
case PORT_IRDA:
regtype = SCIx_IRDA_REGTYPE;
break;
case PORT_SCIFA:
regtype = SCIx_SCIFA_REGTYPE;
break;
case PORT_SCIFB:
regtype = SCIx_SCIFB_REGTYPE;
break;
case PORT_SCIF:
/*
* The SH-4 is a bit of a misnomer here, although that's
* where this particular port layout originated. This
* configuration (or some slight variation thereof)
* remains the dominant model for all SCIFs.
*/
regtype = SCIx_SH4_SCIF_REGTYPE;
break;
case PORT_HSCIF:
regtype = SCIx_HSCIF_REGTYPE;
break;
default:
pr_err("Can't probe register map for given port\n");
return NULL;
}
return &sci_port_params[regtype];
}
static int sci_init_single(struct platform_device *dev,
struct sci_port *sci_port, unsigned int index,
const struct plat_sci_port *p, bool early)
{
struct uart_port *port = &sci_port->port;
const struct resource *res;
unsigned int i;
int ret;
sci_port->cfg = p;
port->ops = &sci_uart_ops;
port->iotype = UPIO_MEM;
port->line = index;
port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_SH_SCI_CONSOLE);
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
if (res == NULL)
return -ENOMEM;
port->mapbase = res->start;
sci_port->reg_size = resource_size(res);
for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) {
if (i)
sci_port->irqs[i] = platform_get_irq_optional(dev, i);
else
sci_port->irqs[i] = platform_get_irq(dev, i);
}
/* The SCI generates several interrupts. They can be muxed together or
* connected to different interrupt lines. In the muxed case only one
* interrupt resource is specified as there is only one interrupt ID.
* In the non-muxed case, up to 6 interrupt signals might be generated
* from the SCI, however those signals might have their own individual
* interrupt ID numbers, or muxed together with another interrupt.
*/
if (sci_port->irqs[0] < 0)
return -ENXIO;
if (sci_port->irqs[1] < 0)
for (i = 1; i < ARRAY_SIZE(sci_port->irqs); i++)
sci_port->irqs[i] = sci_port->irqs[0];
sci_port->params = sci_probe_regmap(p);
if (unlikely(sci_port->params == NULL))
return -EINVAL;
switch (p->type) {
case PORT_SCIFB:
sci_port->rx_trigger = 48;
break;
case PORT_HSCIF:
sci_port->rx_trigger = 64;
break;
case PORT_SCIFA:
sci_port->rx_trigger = 32;
break;
case PORT_SCIF:
if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
/* RX triggering not implemented for this IP */
sci_port->rx_trigger = 1;
else
sci_port->rx_trigger = 8;
break;
default:
sci_port->rx_trigger = 1;
break;
}
sci_port->rx_fifo_timeout = 0;
sci_port->hscif_tot = 0;
/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
* match the SoC datasheet, this should be investigated. Let platform
* data override the sampling rate for now.
*/
sci_port->sampling_rate_mask = p->sampling_rate
? SCI_SR(p->sampling_rate)
: sci_port->params->sampling_rate_mask;
if (!early) {
ret = sci_init_clocks(sci_port, &dev->dev);
if (ret < 0)
return ret;
port->dev = &dev->dev;
pm_runtime_enable(&dev->dev);
}
port->type = p->type;
port->flags = UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
port->fifosize = sci_port->params->fifosize;
if (port->type == PORT_SCI) {
if (sci_port->reg_size >= 0x20)
port->regshift = 2;
else
port->regshift = 1;
}
/*
* The UART port needs an IRQ value, so we peg this to the RX IRQ
* for the multi-IRQ ports, which is where we are primarily
* concerned with the shutdown path synchronization.
*
* For the muxed case there's nothing more to do.
*/
port->irq = sci_port->irqs[SCIx_RXI_IRQ];
port->irqflags = 0;
port->serial_in = sci_serial_in;
port->serial_out = sci_serial_out;
return 0;
}
static void sci_cleanup_single(struct sci_port *port)
{
pm_runtime_disable(port->port.dev);
}
#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
static void serial_console_putchar(struct uart_port *port, unsigned char ch)
{
sci_poll_put_char(port, ch);
}
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*/
static void serial_console_write(struct console *co, const char *s,
unsigned count)
{
struct sci_port *sci_port = &sci_ports[co->index];
struct uart_port *port = &sci_port->port;
unsigned short bits, ctrl, ctrl_temp;
unsigned long flags;
int locked = 1;
if (port->sysrq)
locked = 0;
else if (oops_in_progress)
locked = spin_trylock_irqsave(&port->lock, flags);
else
spin_lock_irqsave(&port->lock, flags);
/* first save SCSCR then disable interrupts, keep clock source */
ctrl = serial_port_in(port, SCSCR);
ctrl_temp = SCSCR_RE | SCSCR_TE |
(sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
(ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
uart_console_write(port, s, count, serial_console_putchar);
/* wait until fifo is empty and last bit has been transmitted */
bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
while ((serial_port_in(port, SCxSR) & bits) != bits)
cpu_relax();
/* restore the SCSCR */
serial_port_out(port, SCSCR, ctrl);
if (locked)
spin_unlock_irqrestore(&port->lock, flags);
}
static int serial_console_setup(struct console *co, char *options)
{
struct sci_port *sci_port;
struct uart_port *port;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
int ret;
/*
* Refuse to handle any bogus ports.
*/
if (co->index < 0 || co->index >= SCI_NPORTS)
return -ENODEV;
sci_port = &sci_ports[co->index];
port = &sci_port->port;
/*
* Refuse to handle uninitialized ports.
*/
if (!port->ops)
return -ENODEV;
ret = sci_remap_port(port);
if (unlikely(ret != 0))
return ret;
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(port, co, baud, parity, bits, flow);
}
static struct console serial_console = {
.name = "ttySC",
.device = uart_console_device,
.write = serial_console_write,
.setup = serial_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &sci_uart_driver,
};
#ifdef CONFIG_SUPERH
static struct console early_serial_console = {
.name = "early_ttySC",
.write = serial_console_write,
.flags = CON_PRINTBUFFER,
.index = -1,
};
static char early_serial_buf[32];
static int sci_probe_earlyprintk(struct platform_device *pdev)
{
const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
if (early_serial_console.data)
return -EEXIST;
early_serial_console.index = pdev->id;
sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
serial_console_setup(&early_serial_console, early_serial_buf);
if (!strstr(early_serial_buf, "keep"))
early_serial_console.flags |= CON_BOOT;
register_console(&early_serial_console);
return 0;
}
#endif
#define SCI_CONSOLE (&serial_console)
#else
static inline int sci_probe_earlyprintk(struct platform_device *pdev)
{
return -EINVAL;
}
#define SCI_CONSOLE NULL
#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
static DEFINE_MUTEX(sci_uart_registration_lock);
static struct uart_driver sci_uart_driver = {
.owner = THIS_MODULE,
.driver_name = "sci",
.dev_name = "ttySC",
.major = SCI_MAJOR,
.minor = SCI_MINOR_START,
.nr = SCI_NPORTS,
.cons = SCI_CONSOLE,
};
static int sci_remove(struct platform_device *dev)
{
struct sci_port *port = platform_get_drvdata(dev);
unsigned int type = port->port.type; /* uart_remove_... clears it */
sci_ports_in_use &= ~BIT(port->port.line);
uart_remove_one_port(&sci_uart_driver, &port->port);
sci_cleanup_single(port);
if (port->port.fifosize > 1)
device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
return 0;
}
#define SCI_OF_DATA(type, regtype) (void *)((type) << 16 | (regtype))
#define SCI_OF_TYPE(data) ((unsigned long)(data) >> 16)
#define SCI_OF_REGTYPE(data) ((unsigned long)(data) & 0xffff)
static const struct of_device_id of_sci_match[] = {
/* SoC-specific types */
{
.compatible = "renesas,scif-r7s72100",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
},
{
.compatible = "renesas,scif-r7s9210",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
},
{
.compatible = "renesas,scif-r9a07g044",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
},
/* Family-specific types */
{
.compatible = "renesas,rcar-gen1-scif",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
}, {
.compatible = "renesas,rcar-gen2-scif",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
}, {
.compatible = "renesas,rcar-gen3-scif",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
}, {
.compatible = "renesas,rcar-gen4-scif",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
},
/* Generic types */
{
.compatible = "renesas,scif",
.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
}, {
.compatible = "renesas,scifa",
.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
}, {
.compatible = "renesas,scifb",
.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
}, {
.compatible = "renesas,hscif",
.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
}, {
.compatible = "renesas,sci",
.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
}, {
/* Terminator */
},
};
MODULE_DEVICE_TABLE(of, of_sci_match);
static void sci_reset_control_assert(void *data)
{
reset_control_assert(data);
}
static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
unsigned int *dev_id)
{
struct device_node *np = pdev->dev.of_node;
struct reset_control *rstc;
struct plat_sci_port *p;
struct sci_port *sp;
const void *data;
int id, ret;
if (!IS_ENABLED(CONFIG_OF) || !np)
return ERR_PTR(-EINVAL);
data = of_device_get_match_data(&pdev->dev);
rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
if (IS_ERR(rstc))
return ERR_PTR(dev_err_probe(&pdev->dev, PTR_ERR(rstc),
"failed to get reset ctrl\n"));
ret = reset_control_deassert(rstc);
if (ret) {
dev_err(&pdev->dev, "failed to deassert reset %d\n", ret);
return ERR_PTR(ret);
}
ret = devm_add_action_or_reset(&pdev->dev, sci_reset_control_assert, rstc);
if (ret) {
dev_err(&pdev->dev, "failed to register assert devm action, %d\n",
ret);
return ERR_PTR(ret);
}
p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
if (!p)
return ERR_PTR(-ENOMEM);
/* Get the line number from the aliases node. */
id = of_alias_get_id(np, "serial");
if (id < 0 && ~sci_ports_in_use)
id = ffz(sci_ports_in_use);
if (id < 0) {
dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
return ERR_PTR(-EINVAL);
}
if (id >= ARRAY_SIZE(sci_ports)) {
dev_err(&pdev->dev, "serial%d out of range\n", id);
return ERR_PTR(-EINVAL);
}
sp = &sci_ports[id];
*dev_id = id;
p->type = SCI_OF_TYPE(data);
p->regtype = SCI_OF_REGTYPE(data);
sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
return p;
}
static int sci_probe_single(struct platform_device *dev,
unsigned int index,
struct plat_sci_port *p,
struct sci_port *sciport)
{
int ret;
/* Sanity check */
if (unlikely(index >= SCI_NPORTS)) {
dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
index+1, SCI_NPORTS);
dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
return -EINVAL;
}
BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
if (sci_ports_in_use & BIT(index))
return -EBUSY;
mutex_lock(&sci_uart_registration_lock);
if (!sci_uart_driver.state) {
ret = uart_register_driver(&sci_uart_driver);
if (ret) {
mutex_unlock(&sci_uart_registration_lock);
return ret;
}
}
mutex_unlock(&sci_uart_registration_lock);
ret = sci_init_single(dev, sciport, index, p, false);
if (ret)
return ret;
sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
if (IS_ERR(sciport->gpios))
return PTR_ERR(sciport->gpios);
if (sciport->has_rtscts) {
if (mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_CTS) ||
mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_RTS)) {
dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
return -EINVAL;
}
sciport->port.flags |= UPF_HARD_FLOW;
}
ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
if (ret) {
sci_cleanup_single(sciport);
return ret;
}
return 0;
}
static int sci_probe(struct platform_device *dev)
{
struct plat_sci_port *p;
struct sci_port *sp;
unsigned int dev_id;
int ret;
/*
* If we've come here via earlyprintk initialization, head off to
* the special early probe. We don't have sufficient device state
* to make it beyond this yet.
*/
#ifdef CONFIG_SUPERH
if (is_sh_early_platform_device(dev))
return sci_probe_earlyprintk(dev);
#endif
if (dev->dev.of_node) {
p = sci_parse_dt(dev, &dev_id);
if (IS_ERR(p))
return PTR_ERR(p);
} else {
p = dev->dev.platform_data;
if (p == NULL) {
dev_err(&dev->dev, "no platform data supplied\n");
return -EINVAL;
}
dev_id = dev->id;
}
sp = &sci_ports[dev_id];
platform_set_drvdata(dev, sp);
ret = sci_probe_single(dev, dev_id, p, sp);
if (ret)
return ret;
if (sp->port.fifosize > 1) {
ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_trigger);
if (ret)
return ret;
}
if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
sp->port.type == PORT_HSCIF) {
ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
if (ret) {
if (sp->port.fifosize > 1) {
device_remove_file(&dev->dev,
&dev_attr_rx_fifo_trigger);
}
return ret;
}
}
#ifdef CONFIG_SH_STANDARD_BIOS
sh_bios_gdb_detach();
#endif
sci_ports_in_use |= BIT(dev_id);
return 0;
}
static __maybe_unused int sci_suspend(struct device *dev)
{
struct sci_port *sport = dev_get_drvdata(dev);
if (sport)
uart_suspend_port(&sci_uart_driver, &sport->port);
return 0;
}
static __maybe_unused int sci_resume(struct device *dev)
{
struct sci_port *sport = dev_get_drvdata(dev);
if (sport)
uart_resume_port(&sci_uart_driver, &sport->port);
return 0;
}
static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
static struct platform_driver sci_driver = {
.probe = sci_probe,
.remove = sci_remove,
.driver = {
.name = "sh-sci",
.pm = &sci_dev_pm_ops,
.of_match_table = of_match_ptr(of_sci_match),
},
};
static int __init sci_init(void)
{
pr_info("%s\n", banner);
return platform_driver_register(&sci_driver);
}
static void __exit sci_exit(void)
{
platform_driver_unregister(&sci_driver);
if (sci_uart_driver.state)
uart_unregister_driver(&sci_uart_driver);
}
#if defined(CONFIG_SUPERH) && defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
sh_early_platform_init_buffer("earlyprintk", &sci_driver,
early_serial_buf, ARRAY_SIZE(early_serial_buf));
#endif
#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
static struct plat_sci_port port_cfg __initdata;
static int __init early_console_setup(struct earlycon_device *device,
int type)
{
if (!device->port.membase)
return -ENODEV;
device->port.serial_in = sci_serial_in;
device->port.serial_out = sci_serial_out;
device->port.type = type;
memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
port_cfg.type = type;
sci_ports[0].cfg = &port_cfg;
sci_ports[0].params = sci_probe_regmap(&port_cfg);
port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
sci_serial_out(&sci_ports[0].port, SCSCR,
SCSCR_RE | SCSCR_TE | port_cfg.scscr);
device->con->write = serial_console_write;
return 0;
}
static int __init sci_early_console_setup(struct earlycon_device *device,
const char *opt)
{
return early_console_setup(device, PORT_SCI);
}
static int __init scif_early_console_setup(struct earlycon_device *device,
const char *opt)
{
return early_console_setup(device, PORT_SCIF);
}
static int __init rzscifa_early_console_setup(struct earlycon_device *device,
const char *opt)
{
port_cfg.regtype = SCIx_RZ_SCIFA_REGTYPE;
return early_console_setup(device, PORT_SCIF);
}
static int __init scifa_early_console_setup(struct earlycon_device *device,
const char *opt)
{
return early_console_setup(device, PORT_SCIFA);
}
static int __init scifb_early_console_setup(struct earlycon_device *device,
const char *opt)
{
return early_console_setup(device, PORT_SCIFB);
}
static int __init hscif_early_console_setup(struct earlycon_device *device,
const char *opt)
{
return early_console_setup(device, PORT_HSCIF);
}
OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rzscifa_early_console_setup);
OF_EARLYCON_DECLARE(scif, "renesas,scif-r9a07g044", rzscifa_early_console_setup);
OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
module_init(sci_init);
module_exit(sci_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:sh-sci");
MODULE_AUTHOR("Paul Mundt");
MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
Reference in New Issue View Git Blame Copy Permalink