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linux/drivers/pci/controller/pci-mvebu.c
Ilpo Järvinen 408599ec56 PCI: mvebu: Use FIELD_PREP() with Link Width 
mvebu_pcie_setup_hw() setups the Maximum Link Width field in the Link
Capabilities registers using an open-coded variant of FIELD_PREP() with
a literal in shift. Improve readability by using
FIELD_PREP(PCI_EXP_LNKCAP_MLW, ...).

Link: https://lore.kernel.org/r/20230919125648.1920-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-10-10 15:00:52 -05:00

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// SPDX-License-Identifier: GPL-2.0
/*
* PCIe driver for Marvell Armada 370 and Armada XP SoCs
*
* Author: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/mbus.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include "../pci.h"
#include "../pci-bridge-emul.h"
/*
* PCIe unit register offsets.
*/
#define PCIE_DEV_ID_OFF 0x0000
#define PCIE_CMD_OFF 0x0004
#define PCIE_DEV_REV_OFF 0x0008
#define PCIE_BAR_LO_OFF(n) (0x0010 + ((n) << 3))
#define PCIE_BAR_HI_OFF(n) (0x0014 + ((n) << 3))
#define PCIE_SSDEV_ID_OFF 0x002c
#define PCIE_CAP_PCIEXP 0x0060
#define PCIE_CAP_PCIERR_OFF 0x0100
#define PCIE_BAR_CTRL_OFF(n) (0x1804 + (((n) - 1) * 4))
#define PCIE_WIN04_CTRL_OFF(n) (0x1820 + ((n) << 4))
#define PCIE_WIN04_BASE_OFF(n) (0x1824 + ((n) << 4))
#define PCIE_WIN04_REMAP_OFF(n) (0x182c + ((n) << 4))
#define PCIE_WIN5_CTRL_OFF 0x1880
#define PCIE_WIN5_BASE_OFF 0x1884
#define PCIE_WIN5_REMAP_OFF 0x188c
#define PCIE_CONF_ADDR_OFF 0x18f8
#define PCIE_CONF_ADDR_EN 0x80000000
#define PCIE_CONF_REG(r) ((((r) & 0xf00) << 16) | ((r) & 0xfc))
#define PCIE_CONF_BUS(b) (((b) & 0xff) << 16)
#define PCIE_CONF_DEV(d) (((d) & 0x1f) << 11)
#define PCIE_CONF_FUNC(f) (((f) & 0x7) << 8)
#define PCIE_CONF_ADDR(bus, devfn, where) \
(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn)) | \
PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \
PCIE_CONF_ADDR_EN)
#define PCIE_CONF_DATA_OFF 0x18fc
#define PCIE_INT_CAUSE_OFF 0x1900
#define PCIE_INT_UNMASK_OFF 0x1910
#define PCIE_INT_INTX(i) BIT(24+i)
#define PCIE_INT_PM_PME BIT(28)
#define PCIE_INT_ALL_MASK GENMASK(31, 0)
#define PCIE_CTRL_OFF 0x1a00
#define PCIE_CTRL_X1_MODE 0x0001
#define PCIE_CTRL_RC_MODE BIT(1)
#define PCIE_CTRL_MASTER_HOT_RESET BIT(24)
#define PCIE_STAT_OFF 0x1a04
#define PCIE_STAT_BUS 0xff00
#define PCIE_STAT_DEV 0x1f0000
#define PCIE_STAT_LINK_DOWN BIT(0)
#define PCIE_SSPL_OFF 0x1a0c
#define PCIE_SSPL_VALUE_SHIFT 0
#define PCIE_SSPL_VALUE_MASK GENMASK(7, 0)
#define PCIE_SSPL_SCALE_SHIFT 8
#define PCIE_SSPL_SCALE_MASK GENMASK(9, 8)
#define PCIE_SSPL_ENABLE BIT(16)
#define PCIE_RC_RTSTA 0x1a14
#define PCIE_DEBUG_CTRL 0x1a60
#define PCIE_DEBUG_SOFT_RESET BIT(20)
struct mvebu_pcie_port;
/* Structure representing all PCIe interfaces */
struct mvebu_pcie {
struct platform_device *pdev;
struct mvebu_pcie_port *ports;
struct resource io;
struct resource realio;
struct resource mem;
int nports;
};
struct mvebu_pcie_window {
phys_addr_t base;
phys_addr_t remap;
size_t size;
};
/* Structure representing one PCIe interface */
struct mvebu_pcie_port {
char *name;
void __iomem *base;
u32 port;
u32 lane;
bool is_x4;
int devfn;
unsigned int mem_target;
unsigned int mem_attr;
unsigned int io_target;
unsigned int io_attr;
struct clk *clk;
struct gpio_desc *reset_gpio;
char *reset_name;
struct pci_bridge_emul bridge;
struct device_node *dn;
struct mvebu_pcie *pcie;
struct mvebu_pcie_window memwin;
struct mvebu_pcie_window iowin;
u32 saved_pcie_stat;
struct resource regs;
u8 slot_power_limit_value;
u8 slot_power_limit_scale;
struct irq_domain *intx_irq_domain;
raw_spinlock_t irq_lock;
int intx_irq;
};
static inline void mvebu_writel(struct mvebu_pcie_port *port, u32 val, u32 reg)
{
writel(val, port->base + reg);
}
static inline u32 mvebu_readl(struct mvebu_pcie_port *port, u32 reg)
{
return readl(port->base + reg);
}
static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port)
{
return port->io_target != -1 && port->io_attr != -1;
}
static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port)
{
return !(mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
}
static u8 mvebu_pcie_get_local_bus_nr(struct mvebu_pcie_port *port)
{
return (mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_BUS) >> 8;
}
static void mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port *port, int nr)
{
u32 stat;
stat = mvebu_readl(port, PCIE_STAT_OFF);
stat &= ~PCIE_STAT_BUS;
stat |= nr << 8;
mvebu_writel(port, stat, PCIE_STAT_OFF);
}
static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr)
{
u32 stat;
stat = mvebu_readl(port, PCIE_STAT_OFF);
stat &= ~PCIE_STAT_DEV;
stat |= nr << 16;
mvebu_writel(port, stat, PCIE_STAT_OFF);
}
static void mvebu_pcie_disable_wins(struct mvebu_pcie_port *port)
{
int i;
mvebu_writel(port, 0, PCIE_BAR_LO_OFF(0));
mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0));
for (i = 1; i < 3; i++) {
mvebu_writel(port, 0, PCIE_BAR_CTRL_OFF(i));
mvebu_writel(port, 0, PCIE_BAR_LO_OFF(i));
mvebu_writel(port, 0, PCIE_BAR_HI_OFF(i));
}
for (i = 0; i < 5; i++) {
mvebu_writel(port, 0, PCIE_WIN04_CTRL_OFF(i));
mvebu_writel(port, 0, PCIE_WIN04_BASE_OFF(i));
mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
}
mvebu_writel(port, 0, PCIE_WIN5_CTRL_OFF);
mvebu_writel(port, 0, PCIE_WIN5_BASE_OFF);
mvebu_writel(port, 0, PCIE_WIN5_REMAP_OFF);
}
/*
* Setup PCIE BARs and Address Decode Wins:
* BAR[0] -> internal registers (needed for MSI)
* BAR[1] -> covers all DRAM banks
* BAR[2] -> Disabled
* WIN[0-3] -> DRAM bank[0-3]
*/
static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port)
{
const struct mbus_dram_target_info *dram;
u32 size;
int i;
dram = mv_mbus_dram_info();
/* First, disable and clear BARs and windows. */
mvebu_pcie_disable_wins(port);
/* Setup windows for DDR banks. Count total DDR size on the fly. */
size = 0;
for (i = 0; i < dram->num_cs; i++) {
const struct mbus_dram_window *cs = dram->cs + i;
mvebu_writel(port, cs->base & 0xffff0000,
PCIE_WIN04_BASE_OFF(i));
mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
mvebu_writel(port,
((cs->size - 1) & 0xffff0000) |
(cs->mbus_attr << 8) |
(dram->mbus_dram_target_id << 4) | 1,
PCIE_WIN04_CTRL_OFF(i));
size += cs->size;
}
/* Round up 'size' to the nearest power of two. */
if ((size & (size - 1)) != 0)
size = 1 << fls(size);
/* Setup BAR[1] to all DRAM banks. */
mvebu_writel(port, dram->cs[0].base, PCIE_BAR_LO_OFF(1));
mvebu_writel(port, 0, PCIE_BAR_HI_OFF(1));
mvebu_writel(port, ((size - 1) & 0xffff0000) | 1,
PCIE_BAR_CTRL_OFF(1));
/*
* Point BAR[0] to the device's internal registers.
*/
mvebu_writel(port, round_down(port->regs.start, SZ_1M), PCIE_BAR_LO_OFF(0));
mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0));
}
static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port)
{
u32 ctrl, lnkcap, cmd, dev_rev, unmask, sspl;
/* Setup PCIe controller to Root Complex mode. */
ctrl = mvebu_readl(port, PCIE_CTRL_OFF);
ctrl |= PCIE_CTRL_RC_MODE;
mvebu_writel(port, ctrl, PCIE_CTRL_OFF);
/*
* Set Maximum Link Width to X1 or X4 in Root Port's PCIe Link
* Capability register. This register is defined by PCIe specification
* as read-only but this mvebu controller has it as read-write and must
* be set to number of SerDes PCIe lanes (1 or 4). If this register is
* not set correctly then link with endpoint card is not established.
*/
lnkcap = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP);
lnkcap &= ~PCI_EXP_LNKCAP_MLW;
lnkcap |= FIELD_PREP(PCI_EXP_LNKCAP_MLW, port->is_x4 ? 4 : 1);
mvebu_writel(port, lnkcap, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP);
/* Disable Root Bridge I/O space, memory space and bus mastering. */
cmd = mvebu_readl(port, PCIE_CMD_OFF);
cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
mvebu_writel(port, cmd, PCIE_CMD_OFF);
/*
* Change Class Code of PCI Bridge device to PCI Bridge (0x6004)
* because default value is Memory controller (0x5080).
*
* Note that this mvebu PCI Bridge does not have compliant Type 1
* Configuration Space. Header Type is reported as Type 0 and it
* has format of Type 0 config space.
*
* Moreover Type 0 BAR registers (ranges 0x10 - 0x28 and 0x30 - 0x34)
* have the same format in Marvell's specification as in PCIe
* specification, but their meaning is totally different and they do
* different things: they are aliased into internal mvebu registers
* (e.g. PCIE_BAR_LO_OFF) and these should not be changed or
* reconfigured by pci device drivers.
*
* Therefore driver uses emulation of PCI Bridge which emulates
* access to configuration space via internal mvebu registers or
* emulated configuration buffer. Driver access these PCI Bridge
* directly for simplification, but these registers can be accessed
* also via standard mvebu way for accessing PCI config space.
*/
dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF);
dev_rev &= ~0xffffff00;
dev_rev |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8;
mvebu_writel(port, dev_rev, PCIE_DEV_REV_OFF);
/* Point PCIe unit MBUS decode windows to DRAM space. */
mvebu_pcie_setup_wins(port);
/*
* Program Root Port to automatically send Set_Slot_Power_Limit
* PCIe Message when changing status from Dl_Down to Dl_Up and valid
* slot power limit was specified.
*/
sspl = mvebu_readl(port, PCIE_SSPL_OFF);
sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE);
if (port->slot_power_limit_value) {
sspl |= port->slot_power_limit_value << PCIE_SSPL_VALUE_SHIFT;
sspl |= port->slot_power_limit_scale << PCIE_SSPL_SCALE_SHIFT;
sspl |= PCIE_SSPL_ENABLE;
}
mvebu_writel(port, sspl, PCIE_SSPL_OFF);
/* Mask all interrupt sources. */
mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF);
/* Clear all interrupt causes. */
mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF);
/* Check if "intx" interrupt was specified in DT. */
if (port->intx_irq > 0)
return;
/*
* Fallback code when "intx" interrupt was not specified in DT:
* Unmask all legacy INTx interrupts as driver does not provide a way
* for masking and unmasking of individual legacy INTx interrupts.
* Legacy INTx are reported via one shared GIC source and therefore
* kernel cannot distinguish which individual legacy INTx was triggered.
* These interrupts are shared, so it should not cause any issue. Just
* performance penalty as every PCIe interrupt handler needs to be
* called when some interrupt is triggered.
*/
unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
unmask |= PCIE_INT_INTX(0) | PCIE_INT_INTX(1) |
PCIE_INT_INTX(2) | PCIE_INT_INTX(3);
mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
}
static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
struct pci_bus *bus,
int devfn);
static int mvebu_pcie_child_rd_conf(struct pci_bus *bus, u32 devfn, int where,
int size, u32 *val)
{
struct mvebu_pcie *pcie = bus->sysdata;
struct mvebu_pcie_port *port;
void __iomem *conf_data;
port = mvebu_pcie_find_port(pcie, bus, devfn);
if (!port)
return PCIBIOS_DEVICE_NOT_FOUND;
if (!mvebu_pcie_link_up(port))
return PCIBIOS_DEVICE_NOT_FOUND;
conf_data = port->base + PCIE_CONF_DATA_OFF;
mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
PCIE_CONF_ADDR_OFF);
switch (size) {
case 1:
*val = readb_relaxed(conf_data + (where & 3));
break;
case 2:
*val = readw_relaxed(conf_data + (where & 2));
break;
case 4:
*val = readl_relaxed(conf_data);
break;
default:
return PCIBIOS_BAD_REGISTER_NUMBER;
}
return PCIBIOS_SUCCESSFUL;
}
static int mvebu_pcie_child_wr_conf(struct pci_bus *bus, u32 devfn,
int where, int size, u32 val)
{
struct mvebu_pcie *pcie = bus->sysdata;
struct mvebu_pcie_port *port;
void __iomem *conf_data;
port = mvebu_pcie_find_port(pcie, bus, devfn);
if (!port)
return PCIBIOS_DEVICE_NOT_FOUND;
if (!mvebu_pcie_link_up(port))
return PCIBIOS_DEVICE_NOT_FOUND;
conf_data = port->base + PCIE_CONF_DATA_OFF;
mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
PCIE_CONF_ADDR_OFF);
switch (size) {
case 1:
writeb(val, conf_data + (where & 3));
break;
case 2:
writew(val, conf_data + (where & 2));
break;
case 4:
writel(val, conf_data);
break;
default:
return PCIBIOS_BAD_REGISTER_NUMBER;
}
return PCIBIOS_SUCCESSFUL;
}
static struct pci_ops mvebu_pcie_child_ops = {
.read = mvebu_pcie_child_rd_conf,
.write = mvebu_pcie_child_wr_conf,
};
/*
* Remove windows, starting from the largest ones to the smallest
* ones.
*/
static void mvebu_pcie_del_windows(struct mvebu_pcie_port *port,
phys_addr_t base, size_t size)
{
while (size) {
size_t sz = 1 << (fls(size) - 1);
mvebu_mbus_del_window(base, sz);
base += sz;
size -= sz;
}
}
/*
* MBus windows can only have a power of two size, but PCI BARs do not
* have this constraint. Therefore, we have to split the PCI BAR into
* areas each having a power of two size. We start from the largest
* one (i.e highest order bit set in the size).
*/
static int mvebu_pcie_add_windows(struct mvebu_pcie_port *port,
unsigned int target, unsigned int attribute,
phys_addr_t base, size_t size,
phys_addr_t remap)
{
size_t size_mapped = 0;
while (size) {
size_t sz = 1 << (fls(size) - 1);
int ret;
ret = mvebu_mbus_add_window_remap_by_id(target, attribute, base,
sz, remap);
if (ret) {
phys_addr_t end = base + sz - 1;
dev_err(&port->pcie->pdev->dev,
"Could not create MBus window at [mem %pa-%pa]: %d\n",
&base, &end, ret);
mvebu_pcie_del_windows(port, base - size_mapped,
size_mapped);
return ret;
}
size -= sz;
size_mapped += sz;
base += sz;
if (remap != MVEBU_MBUS_NO_REMAP)
remap += sz;
}
return 0;
}
static int mvebu_pcie_set_window(struct mvebu_pcie_port *port,
unsigned int target, unsigned int attribute,
const struct mvebu_pcie_window *desired,
struct mvebu_pcie_window *cur)
{
int ret;
if (desired->base == cur->base && desired->remap == cur->remap &&
desired->size == cur->size)
return 0;
if (cur->size != 0) {
mvebu_pcie_del_windows(port, cur->base, cur->size);
cur->size = 0;
cur->base = 0;
/*
* If something tries to change the window while it is enabled
* the change will not be done atomically. That would be
* difficult to do in the general case.
*/
}
if (desired->size == 0)
return 0;
ret = mvebu_pcie_add_windows(port, target, attribute, desired->base,
desired->size, desired->remap);
if (ret) {
cur->size = 0;
cur->base = 0;
return ret;
}
*cur = *desired;
return 0;
}
static int mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port)
{
struct mvebu_pcie_window desired = {};
struct pci_bridge_emul_conf *conf = &port->bridge.conf;
/* Are the new iobase/iolimit values invalid? */
if (conf->iolimit < conf->iobase ||
le16_to_cpu(conf->iolimitupper) < le16_to_cpu(conf->iobaseupper))
return mvebu_pcie_set_window(port, port->io_target, port->io_attr,
&desired, &port->iowin);
/*
* We read the PCI-to-PCI bridge emulated registers, and
* calculate the base address and size of the address decoding
* window to setup, according to the PCI-to-PCI bridge
* specifications. iobase is the bus address, port->iowin_base
* is the CPU address.
*/
desired.remap = ((conf->iobase & 0xF0) << 8) |
(le16_to_cpu(conf->iobaseupper) << 16);
desired.base = port->pcie->io.start + desired.remap;
desired.size = ((0xFFF | ((conf->iolimit & 0xF0) << 8) |
(le16_to_cpu(conf->iolimitupper) << 16)) -
desired.remap) +
1;
return mvebu_pcie_set_window(port, port->io_target, port->io_attr, &desired,
&port->iowin);
}
static int mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port)
{
struct mvebu_pcie_window desired = {.remap = MVEBU_MBUS_NO_REMAP};
struct pci_bridge_emul_conf *conf = &port->bridge.conf;
/* Are the new membase/memlimit values invalid? */
if (le16_to_cpu(conf->memlimit) < le16_to_cpu(conf->membase))
return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr,
&desired, &port->memwin);
/*
* We read the PCI-to-PCI bridge emulated registers, and
* calculate the base address and size of the address decoding
* window to setup, according to the PCI-to-PCI bridge
* specifications.
*/
desired.base = ((le16_to_cpu(conf->membase) & 0xFFF0) << 16);
desired.size = (((le16_to_cpu(conf->memlimit) & 0xFFF0) << 16) | 0xFFFFF) -
desired.base + 1;
return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr, &desired,
&port->memwin);
}
static pci_bridge_emul_read_status_t
mvebu_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge,
int reg, u32 *value)
{
struct mvebu_pcie_port *port = bridge->data;
switch (reg) {
case PCI_COMMAND:
*value = mvebu_readl(port, PCIE_CMD_OFF);
break;
case PCI_PRIMARY_BUS: {
/*
* From the whole 32bit register we support reading from HW only
* secondary bus number which is mvebu local bus number.
* Other bits are retrieved only from emulated config buffer.
*/
__le32 *cfgspace = (__le32 *)&bridge->conf;
u32 val = le32_to_cpu(cfgspace[PCI_PRIMARY_BUS / 4]);
val &= ~0xff00;
val |= mvebu_pcie_get_local_bus_nr(port) << 8;
*value = val;
break;
}
case PCI_INTERRUPT_LINE: {
/*
* From the whole 32bit register we support reading from HW only
* one bit: PCI_BRIDGE_CTL_BUS_RESET.
* Other bits are retrieved only from emulated config buffer.
*/
__le32 *cfgspace = (__le32 *)&bridge->conf;
u32 val = le32_to_cpu(cfgspace[PCI_INTERRUPT_LINE / 4]);
if (mvebu_readl(port, PCIE_CTRL_OFF) & PCIE_CTRL_MASTER_HOT_RESET)
val |= PCI_BRIDGE_CTL_BUS_RESET << 16;
else
val &= ~(PCI_BRIDGE_CTL_BUS_RESET << 16);
*value = val;
break;
}
default:
return PCI_BRIDGE_EMUL_NOT_HANDLED;
}
return PCI_BRIDGE_EMUL_HANDLED;
}
static pci_bridge_emul_read_status_t
mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
int reg, u32 *value)
{
struct mvebu_pcie_port *port = bridge->data;
switch (reg) {
case PCI_EXP_DEVCAP:
*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP);
break;
case PCI_EXP_DEVCTL:
*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
break;
case PCI_EXP_LNKCAP:
/*
* PCIe requires that the Clock Power Management capability bit
* is hard-wired to zero for downstream ports but HW returns 1.
* Additionally enable Data Link Layer Link Active Reporting
* Capable bit as DL_Active indication is provided too.
*/
*value = (mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) &
~PCI_EXP_LNKCAP_CLKPM) | PCI_EXP_LNKCAP_DLLLARC;
break;
case PCI_EXP_LNKCTL:
/* DL_Active indication is provided via PCIE_STAT_OFF */
*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL) |
(mvebu_pcie_link_up(port) ?
(PCI_EXP_LNKSTA_DLLLA << 16) : 0);
break;
case PCI_EXP_SLTCTL: {
u16 slotctl = le16_to_cpu(bridge->pcie_conf.slotctl);
u16 slotsta = le16_to_cpu(bridge->pcie_conf.slotsta);
u32 val = 0;
/*
* When slot power limit was not specified in DT then
* ASPL_DISABLE bit is stored only in emulated config space.
* Otherwise reflect status of PCIE_SSPL_ENABLE bit in HW.
*/
if (!port->slot_power_limit_value)
val |= slotctl & PCI_EXP_SLTCTL_ASPL_DISABLE;
else if (!(mvebu_readl(port, PCIE_SSPL_OFF) & PCIE_SSPL_ENABLE))
val |= PCI_EXP_SLTCTL_ASPL_DISABLE;
/* This callback is 32-bit and in high bits is slot status. */
val |= slotsta << 16;
*value = val;
break;
}
case PCI_EXP_RTSTA:
*value = mvebu_readl(port, PCIE_RC_RTSTA);
break;
case PCI_EXP_DEVCAP2:
*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP2);
break;
case PCI_EXP_DEVCTL2:
*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
break;
case PCI_EXP_LNKCTL2:
*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
break;
default:
return PCI_BRIDGE_EMUL_NOT_HANDLED;
}
return PCI_BRIDGE_EMUL_HANDLED;
}
static pci_bridge_emul_read_status_t
mvebu_pci_bridge_emul_ext_conf_read(struct pci_bridge_emul *bridge,
int reg, u32 *value)
{
struct mvebu_pcie_port *port = bridge->data;
switch (reg) {
case 0:
case PCI_ERR_UNCOR_STATUS:
case PCI_ERR_UNCOR_MASK:
case PCI_ERR_UNCOR_SEVER:
case PCI_ERR_COR_STATUS:
case PCI_ERR_COR_MASK:
case PCI_ERR_CAP:
case PCI_ERR_HEADER_LOG+0:
case PCI_ERR_HEADER_LOG+4:
case PCI_ERR_HEADER_LOG+8:
case PCI_ERR_HEADER_LOG+12:
case PCI_ERR_ROOT_COMMAND:
case PCI_ERR_ROOT_STATUS:
case PCI_ERR_ROOT_ERR_SRC:
*value = mvebu_readl(port, PCIE_CAP_PCIERR_OFF + reg);
break;
default:
return PCI_BRIDGE_EMUL_NOT_HANDLED;
}
return PCI_BRIDGE_EMUL_HANDLED;
}
static void
mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
int reg, u32 old, u32 new, u32 mask)
{
struct mvebu_pcie_port *port = bridge->data;
struct pci_bridge_emul_conf *conf = &bridge->conf;
switch (reg) {
case PCI_COMMAND:
mvebu_writel(port, new, PCIE_CMD_OFF);
break;
case PCI_IO_BASE:
if ((mask & 0xffff) && mvebu_has_ioport(port) &&
mvebu_pcie_handle_iobase_change(port)) {
/* On error disable IO range */
conf->iobase &= ~0xf0;
conf->iolimit &= ~0xf0;
conf->iobase |= 0xf0;
conf->iobaseupper = cpu_to_le16(0x0000);
conf->iolimitupper = cpu_to_le16(0x0000);
}
break;
case PCI_MEMORY_BASE:
if (mvebu_pcie_handle_membase_change(port)) {
/* On error disable mem range */
conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) & ~0xfff0);
conf->memlimit = cpu_to_le16(le16_to_cpu(conf->memlimit) & ~0xfff0);
conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) | 0xfff0);
}
break;
case PCI_IO_BASE_UPPER16:
if (mvebu_has_ioport(port) &&
mvebu_pcie_handle_iobase_change(port)) {
/* On error disable IO range */
conf->iobase &= ~0xf0;
conf->iolimit &= ~0xf0;
conf->iobase |= 0xf0;
conf->iobaseupper = cpu_to_le16(0x0000);
conf->iolimitupper = cpu_to_le16(0x0000);
}
break;
case PCI_PRIMARY_BUS:
if (mask & 0xff00)
mvebu_pcie_set_local_bus_nr(port, conf->secondary_bus);
break;
case PCI_INTERRUPT_LINE:
if (mask & (PCI_BRIDGE_CTL_BUS_RESET << 16)) {
u32 ctrl = mvebu_readl(port, PCIE_CTRL_OFF);
if (new & (PCI_BRIDGE_CTL_BUS_RESET << 16))
ctrl |= PCIE_CTRL_MASTER_HOT_RESET;
else
ctrl &= ~PCIE_CTRL_MASTER_HOT_RESET;
mvebu_writel(port, ctrl, PCIE_CTRL_OFF);
}
break;
default:
break;
}
}
static void
mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
int reg, u32 old, u32 new, u32 mask)
{
struct mvebu_pcie_port *port = bridge->data;
switch (reg) {
case PCI_EXP_DEVCTL:
mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
break;
case PCI_EXP_LNKCTL:
/*
* PCIe requires that the Enable Clock Power Management bit
* is hard-wired to zero for downstream ports but HW allows
* to change it.
*/
new &= ~PCI_EXP_LNKCTL_CLKREQ_EN;
mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL);
break;
case PCI_EXP_SLTCTL:
/*
* Allow to change PCIE_SSPL_ENABLE bit only when slot power
* limit was specified in DT and configured into HW.
*/
if ((mask & PCI_EXP_SLTCTL_ASPL_DISABLE) &&
port->slot_power_limit_value) {
u32 sspl = mvebu_readl(port, PCIE_SSPL_OFF);
if (new & PCI_EXP_SLTCTL_ASPL_DISABLE)
sspl &= ~PCIE_SSPL_ENABLE;
else
sspl |= PCIE_SSPL_ENABLE;
mvebu_writel(port, sspl, PCIE_SSPL_OFF);
}
break;
case PCI_EXP_RTSTA:
/*
* PME Status bit in Root Status Register (PCIE_RC_RTSTA)
* is read-only and can be cleared only by writing 0b to the
* Interrupt Cause RW0C register (PCIE_INT_CAUSE_OFF). So
* clear PME via Interrupt Cause.
*/
if (new & PCI_EXP_RTSTA_PME)
mvebu_writel(port, ~PCIE_INT_PM_PME, PCIE_INT_CAUSE_OFF);
break;
case PCI_EXP_DEVCTL2:
mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
break;
case PCI_EXP_LNKCTL2:
mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
break;
default:
break;
}
}
static void
mvebu_pci_bridge_emul_ext_conf_write(struct pci_bridge_emul *bridge,
int reg, u32 old, u32 new, u32 mask)
{
struct mvebu_pcie_port *port = bridge->data;
switch (reg) {
/* These are W1C registers, so clear other bits */
case PCI_ERR_UNCOR_STATUS:
case PCI_ERR_COR_STATUS:
case PCI_ERR_ROOT_STATUS:
new &= mask;
fallthrough;
case PCI_ERR_UNCOR_MASK:
case PCI_ERR_UNCOR_SEVER:
case PCI_ERR_COR_MASK:
case PCI_ERR_CAP:
case PCI_ERR_HEADER_LOG+0:
case PCI_ERR_HEADER_LOG+4:
case PCI_ERR_HEADER_LOG+8:
case PCI_ERR_HEADER_LOG+12:
case PCI_ERR_ROOT_COMMAND:
case PCI_ERR_ROOT_ERR_SRC:
mvebu_writel(port, new, PCIE_CAP_PCIERR_OFF + reg);
break;
default:
break;
}
}
static const struct pci_bridge_emul_ops mvebu_pci_bridge_emul_ops = {
.read_base = mvebu_pci_bridge_emul_base_conf_read,
.write_base = mvebu_pci_bridge_emul_base_conf_write,
.read_pcie = mvebu_pci_bridge_emul_pcie_conf_read,
.write_pcie = mvebu_pci_bridge_emul_pcie_conf_write,
.read_ext = mvebu_pci_bridge_emul_ext_conf_read,
.write_ext = mvebu_pci_bridge_emul_ext_conf_write,
};
/*
* Initialize the configuration space of the PCI-to-PCI bridge
* associated with the given PCIe interface.
*/
static int mvebu_pci_bridge_emul_init(struct mvebu_pcie_port *port)
{
unsigned int bridge_flags = PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD;
struct pci_bridge_emul *bridge = &port->bridge;
u32 dev_id = mvebu_readl(port, PCIE_DEV_ID_OFF);
u32 dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF);
u32 ssdev_id = mvebu_readl(port, PCIE_SSDEV_ID_OFF);
u32 pcie_cap = mvebu_readl(port, PCIE_CAP_PCIEXP);
u8 pcie_cap_ver = ((pcie_cap >> 16) & PCI_EXP_FLAGS_VERS);
bridge->conf.vendor = cpu_to_le16(dev_id & 0xffff);
bridge->conf.device = cpu_to_le16(dev_id >> 16);
bridge->conf.class_revision = cpu_to_le32(dev_rev & 0xff);
if (mvebu_has_ioport(port)) {
/* We support 32 bits I/O addressing */
bridge->conf.iobase = PCI_IO_RANGE_TYPE_32;
bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32;
} else {
bridge_flags |= PCI_BRIDGE_EMUL_NO_IO_FORWARD;
}
/*
* Older mvebu hardware provides PCIe Capability structure only in
* version 1. New hardware provides it in version 2.
* Enable slot support which is emulated.
*/
bridge->pcie_conf.cap = cpu_to_le16(pcie_cap_ver | PCI_EXP_FLAGS_SLOT);
/*
* Set Presence Detect State bit permanently as there is no support for
* unplugging PCIe card from the slot. Assume that PCIe card is always
* connected in slot.
*
* Set physical slot number to port+1 as mvebu ports are indexed from
* zero and zero value is reserved for ports within the same silicon
* as Root Port which is not mvebu case.
*
* Also set correct slot power limit.
*/
bridge->pcie_conf.slotcap = cpu_to_le32(
FIELD_PREP(PCI_EXP_SLTCAP_SPLV, port->slot_power_limit_value) |
FIELD_PREP(PCI_EXP_SLTCAP_SPLS, port->slot_power_limit_scale) |
FIELD_PREP(PCI_EXP_SLTCAP_PSN, port->port+1));
bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS);
bridge->subsystem_vendor_id = ssdev_id & 0xffff;
bridge->subsystem_id = ssdev_id >> 16;
bridge->has_pcie = true;
bridge->pcie_start = PCIE_CAP_PCIEXP;
bridge->data = port;
bridge->ops = &mvebu_pci_bridge_emul_ops;
return pci_bridge_emul_init(bridge, bridge_flags);
}
static inline struct mvebu_pcie *sys_to_pcie(struct pci_sys_data *sys)
{
return sys->private_data;
}
static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
struct pci_bus *bus,
int devfn)
{
int i;
for (i = 0; i < pcie->nports; i++) {
struct mvebu_pcie_port *port = &pcie->ports[i];
if (!port->base)
continue;
if (bus->number == 0 && port->devfn == devfn)
return port;
if (bus->number != 0 &&
bus->number >= port->bridge.conf.secondary_bus &&
bus->number <= port->bridge.conf.subordinate_bus)
return port;
}
return NULL;
}
/* PCI configuration space write function */
static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
int where, int size, u32 val)
{
struct mvebu_pcie *pcie = bus->sysdata;
struct mvebu_pcie_port *port;
port = mvebu_pcie_find_port(pcie, bus, devfn);
if (!port)
return PCIBIOS_DEVICE_NOT_FOUND;
return pci_bridge_emul_conf_write(&port->bridge, where, size, val);
}
/* PCI configuration space read function */
static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
int size, u32 *val)
{
struct mvebu_pcie *pcie = bus->sysdata;
struct mvebu_pcie_port *port;
port = mvebu_pcie_find_port(pcie, bus, devfn);
if (!port)
return PCIBIOS_DEVICE_NOT_FOUND;
return pci_bridge_emul_conf_read(&port->bridge, where, size, val);
}
static struct pci_ops mvebu_pcie_ops = {
.read = mvebu_pcie_rd_conf,
.write = mvebu_pcie_wr_conf,
};
static void mvebu_pcie_intx_irq_mask(struct irq_data *d)
{
struct mvebu_pcie_port *port = d->domain->host_data;
irq_hw_number_t hwirq = irqd_to_hwirq(d);
unsigned long flags;
u32 unmask;
raw_spin_lock_irqsave(&port->irq_lock, flags);
unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
unmask &= ~PCIE_INT_INTX(hwirq);
mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
raw_spin_unlock_irqrestore(&port->irq_lock, flags);
}
static void mvebu_pcie_intx_irq_unmask(struct irq_data *d)
{
struct mvebu_pcie_port *port = d->domain->host_data;
irq_hw_number_t hwirq = irqd_to_hwirq(d);
unsigned long flags;
u32 unmask;
raw_spin_lock_irqsave(&port->irq_lock, flags);
unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
unmask |= PCIE_INT_INTX(hwirq);
mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
raw_spin_unlock_irqrestore(&port->irq_lock, flags);
}
static struct irq_chip intx_irq_chip = {
.name = "mvebu-INTx",
.irq_mask = mvebu_pcie_intx_irq_mask,
.irq_unmask = mvebu_pcie_intx_irq_unmask,
};
static int mvebu_pcie_intx_irq_map(struct irq_domain *h,
unsigned int virq, irq_hw_number_t hwirq)
{
struct mvebu_pcie_port *port = h->host_data;
irq_set_status_flags(virq, IRQ_LEVEL);
irq_set_chip_and_handler(virq, &intx_irq_chip, handle_level_irq);
irq_set_chip_data(virq, port);
return 0;
}
static const struct irq_domain_ops mvebu_pcie_intx_irq_domain_ops = {
.map = mvebu_pcie_intx_irq_map,
.xlate = irq_domain_xlate_onecell,
};
static int mvebu_pcie_init_irq_domain(struct mvebu_pcie_port *port)
{
struct device *dev = &port->pcie->pdev->dev;
struct device_node *pcie_intc_node;
raw_spin_lock_init(&port->irq_lock);
pcie_intc_node = of_get_next_child(port->dn, NULL);
if (!pcie_intc_node) {
dev_err(dev, "No PCIe Intc node found for %s\n", port->name);
return -ENODEV;
}
port->intx_irq_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
&mvebu_pcie_intx_irq_domain_ops,
port);
of_node_put(pcie_intc_node);
if (!port->intx_irq_domain) {
dev_err(dev, "Failed to get INTx IRQ domain for %s\n", port->name);
return -ENOMEM;
}
return 0;
}
static void mvebu_pcie_irq_handler(struct irq_desc *desc)
{
struct mvebu_pcie_port *port = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
struct device *dev = &port->pcie->pdev->dev;
u32 cause, unmask, status;
int i;
chained_irq_enter(chip, desc);
cause = mvebu_readl(port, PCIE_INT_CAUSE_OFF);
unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
status = cause & unmask;
/* Process legacy INTx interrupts */
for (i = 0; i < PCI_NUM_INTX; i++) {
if (!(status & PCIE_INT_INTX(i)))
continue;
if (generic_handle_domain_irq(port->intx_irq_domain, i) == -EINVAL)
dev_err_ratelimited(dev, "unexpected INT%c IRQ\n", (char)i+'A');
}
chained_irq_exit(chip, desc);
}
static int mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
/* Interrupt support on mvebu emulated bridges is not implemented yet */
if (dev->bus->number == 0)
return 0; /* Proper return code 0 == NO_IRQ */
return of_irq_parse_and_map_pci(dev, slot, pin);
}
static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev,
const struct resource *res,
resource_size_t start,
resource_size_t size,
resource_size_t align)
{
if (dev->bus->number != 0)
return start;
/*
* On the PCI-to-PCI bridge side, the I/O windows must have at
* least a 64 KB size and the memory windows must have at
* least a 1 MB size. Moreover, MBus windows need to have a
* base address aligned on their size, and their size must be
* a power of two. This means that if the BAR doesn't have a
* power of two size, several MBus windows will actually be
* created. We need to ensure that the biggest MBus window
* (which will be the first one) is aligned on its size, which
* explains the rounddown_pow_of_two() being done here.
*/
if (res->flags & IORESOURCE_IO)
return round_up(start, max_t(resource_size_t, SZ_64K,
rounddown_pow_of_two(size)));
else if (res->flags & IORESOURCE_MEM)
return round_up(start, max_t(resource_size_t, SZ_1M,
rounddown_pow_of_two(size)));
else
return start;
}
static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev,
struct device_node *np,
struct mvebu_pcie_port *port)
{
int ret = 0;
ret = of_address_to_resource(np, 0, &port->regs);
if (ret)
return (void __iomem *)ERR_PTR(ret);
return devm_ioremap_resource(&pdev->dev, &port->regs);
}
#define DT_FLAGS_TO_TYPE(flags) (((flags) >> 24) & 0x03)
#define DT_TYPE_IO 0x1
#define DT_TYPE_MEM32 0x2
#define DT_CPUADDR_TO_TARGET(cpuaddr) (((cpuaddr) >> 56) & 0xFF)
#define DT_CPUADDR_TO_ATTR(cpuaddr) (((cpuaddr) >> 48) & 0xFF)
static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
unsigned long type,
unsigned int *tgt,
unsigned int *attr)
{
const int na = 3, ns = 2;
const __be32 *range;
int rlen, nranges, rangesz, pna, i;
*tgt = -1;
*attr = -1;
range = of_get_property(np, "ranges", &rlen);
if (!range)
return -EINVAL;
pna = of_n_addr_cells(np);
rangesz = pna + na + ns;
nranges = rlen / sizeof(__be32) / rangesz;
for (i = 0; i < nranges; i++, range += rangesz) {
u32 flags = of_read_number(range, 1);
u32 slot = of_read_number(range + 1, 1);
u64 cpuaddr = of_read_number(range + na, pna);
unsigned long rtype;
if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO)
rtype = IORESOURCE_IO;
else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32)
rtype = IORESOURCE_MEM;
else
continue;
if (slot == PCI_SLOT(devfn) && type == rtype) {
*tgt = DT_CPUADDR_TO_TARGET(cpuaddr);
*attr = DT_CPUADDR_TO_ATTR(cpuaddr);
return 0;
}
}
return -ENOENT;
}
static int mvebu_pcie_suspend(struct device *dev)
{
struct mvebu_pcie *pcie;
int i;
pcie = dev_get_drvdata(dev);
for (i = 0; i < pcie->nports; i++) {
struct mvebu_pcie_port *port = pcie->ports + i;
if (!port->base)
continue;
port->saved_pcie_stat = mvebu_readl(port, PCIE_STAT_OFF);
}
return 0;
}
static int mvebu_pcie_resume(struct device *dev)
{
struct mvebu_pcie *pcie;
int i;
pcie = dev_get_drvdata(dev);
for (i = 0; i < pcie->nports; i++) {
struct mvebu_pcie_port *port = pcie->ports + i;
if (!port->base)
continue;
mvebu_writel(port, port->saved_pcie_stat, PCIE_STAT_OFF);
mvebu_pcie_setup_hw(port);
}
return 0;
}
static void mvebu_pcie_port_clk_put(void *data)
{
struct mvebu_pcie_port *port = data;
clk_put(port->clk);
}
static int mvebu_pcie_parse_port(struct mvebu_pcie *pcie,
struct mvebu_pcie_port *port, struct device_node *child)
{
struct device *dev = &pcie->pdev->dev;
u32 slot_power_limit;
int ret;
u32 num_lanes;
port->pcie = pcie;
if (of_property_read_u32(child, "marvell,pcie-port", &port->port)) {
dev_warn(dev, "ignoring %pOF, missing pcie-port property\n",
child);
goto skip;
}
if (of_property_read_u32(child, "marvell,pcie-lane", &port->lane))
port->lane = 0;
if (!of_property_read_u32(child, "num-lanes", &num_lanes) && num_lanes == 4)
port->is_x4 = true;
port->name = devm_kasprintf(dev, GFP_KERNEL, "pcie%d.%d", port->port,
port->lane);
if (!port->name) {
ret = -ENOMEM;
goto err;
}
port->devfn = of_pci_get_devfn(child);
if (port->devfn < 0)
goto skip;
if (PCI_FUNC(port->devfn) != 0) {
dev_err(dev, "%s: invalid function number, must be zero\n",
port->name);
goto skip;
}
ret = mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_MEM,
&port->mem_target, &port->mem_attr);
if (ret < 0) {
dev_err(dev, "%s: cannot get tgt/attr for mem window\n",
port->name);
goto skip;
}
if (resource_size(&pcie->io) != 0) {
mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_IO,
&port->io_target, &port->io_attr);
} else {
port->io_target = -1;
port->io_attr = -1;
}
/*
* Old DT bindings do not contain "intx" interrupt
* so do not fail probing driver when interrupt does not exist.
*/
port->intx_irq = of_irq_get_byname(child, "intx");
if (port->intx_irq == -EPROBE_DEFER) {
ret = port->intx_irq;
goto err;
}
if (port->intx_irq <= 0) {
dev_warn(dev, "%s: legacy INTx interrupts cannot be masked individually, "
"%pOF does not contain intx interrupt\n",
port->name, child);
}
port->reset_name = devm_kasprintf(dev, GFP_KERNEL, "%s-reset",
port->name);
if (!port->reset_name) {
ret = -ENOMEM;
goto err;
}
port->reset_gpio = devm_fwnode_gpiod_get(dev, of_fwnode_handle(child),
"reset", GPIOD_OUT_HIGH,
port->name);
ret = PTR_ERR_OR_ZERO(port->reset_gpio);
if (ret) {
if (ret != -ENOENT)
goto err;
/* reset gpio is optional */
port->reset_gpio = NULL;
devm_kfree(dev, port->reset_name);
port->reset_name = NULL;
}
slot_power_limit = of_pci_get_slot_power_limit(child,
&port->slot_power_limit_value,
&port->slot_power_limit_scale);
if (slot_power_limit)
dev_info(dev, "%s: Slot power limit %u.%uW\n",
port->name,
slot_power_limit / 1000,
(slot_power_limit / 100) % 10);
port->clk = of_clk_get_by_name(child, NULL);
if (IS_ERR(port->clk)) {
dev_err(dev, "%s: cannot get clock\n", port->name);
goto skip;
}
ret = devm_add_action(dev, mvebu_pcie_port_clk_put, port);
if (ret < 0) {
clk_put(port->clk);
goto err;
}
return 1;
skip:
ret = 0;
/* In the case of skipping, we need to free these */
devm_kfree(dev, port->reset_name);
port->reset_name = NULL;
devm_kfree(dev, port->name);
port->name = NULL;
err:
return ret;
}
/*
* Power up a PCIe port. PCIe requires the refclk to be stable for 100µs
* prior to releasing PERST. See table 2-4 in section 2.6.2 AC Specifications
* of the PCI Express Card Electromechanical Specification, 1.1.
*/
static int mvebu_pcie_powerup(struct mvebu_pcie_port *port)
{
int ret;
ret = clk_prepare_enable(port->clk);
if (ret < 0)
return ret;
if (port->reset_gpio) {
u32 reset_udelay = PCI_PM_D3COLD_WAIT * 1000;
of_property_read_u32(port->dn, "reset-delay-us",
&reset_udelay);
udelay(100);
gpiod_set_value_cansleep(port->reset_gpio, 0);
msleep(reset_udelay / 1000);
}
return 0;
}
/*
* Power down a PCIe port. Strictly, PCIe requires us to place the card
* in D3hot state before asserting PERST#.
*/
static void mvebu_pcie_powerdown(struct mvebu_pcie_port *port)
{
gpiod_set_value_cansleep(port->reset_gpio, 1);
clk_disable_unprepare(port->clk);
}
/*
* devm_of_pci_get_host_bridge_resources() only sets up translateable resources,
* so we need extra resource setup parsing our special DT properties encoding
* the MEM and IO apertures.
*/
static int mvebu_pcie_parse_request_resources(struct mvebu_pcie *pcie)
{
struct device *dev = &pcie->pdev->dev;
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
int ret;
/* Get the PCIe memory aperture */
mvebu_mbus_get_pcie_mem_aperture(&pcie->mem);
if (resource_size(&pcie->mem) == 0) {
dev_err(dev, "invalid memory aperture size\n");
return -EINVAL;
}
pcie->mem.name = "PCI MEM";
pci_add_resource(&bridge->windows, &pcie->mem);
ret = devm_request_resource(dev, &iomem_resource, &pcie->mem);
if (ret)
return ret;
/* Get the PCIe IO aperture */
mvebu_mbus_get_pcie_io_aperture(&pcie->io);
if (resource_size(&pcie->io) != 0) {
pcie->realio.flags = pcie->io.flags;
pcie->realio.start = PCIBIOS_MIN_IO;
pcie->realio.end = min_t(resource_size_t,
IO_SPACE_LIMIT - SZ_64K,
resource_size(&pcie->io) - 1);
pcie->realio.name = "PCI I/O";
ret = devm_pci_remap_iospace(dev, &pcie->realio, pcie->io.start);
if (ret)
return ret;
pci_add_resource(&bridge->windows, &pcie->realio);
ret = devm_request_resource(dev, &ioport_resource, &pcie->realio);
if (ret)
return ret;
}
return 0;
}
static int mvebu_pcie_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct mvebu_pcie *pcie;
struct pci_host_bridge *bridge;
struct device_node *np = dev->of_node;
struct device_node *child;
int num, i, ret;
bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct mvebu_pcie));
if (!bridge)
return -ENOMEM;
pcie = pci_host_bridge_priv(bridge);
pcie->pdev = pdev;
platform_set_drvdata(pdev, pcie);
ret = mvebu_pcie_parse_request_resources(pcie);
if (ret)
return ret;
num = of_get_available_child_count(np);
pcie->ports = devm_kcalloc(dev, num, sizeof(*pcie->ports), GFP_KERNEL);
if (!pcie->ports)
return -ENOMEM;
i = 0;
for_each_available_child_of_node(np, child) {
struct mvebu_pcie_port *port = &pcie->ports[i];
ret = mvebu_pcie_parse_port(pcie, port, child);
if (ret < 0) {
of_node_put(child);
return ret;
} else if (ret == 0) {
continue;
}
port->dn = child;
i++;
}
pcie->nports = i;
for (i = 0; i < pcie->nports; i++) {
struct mvebu_pcie_port *port = &pcie->ports[i];
int irq = port->intx_irq;
child = port->dn;
if (!child)
continue;
ret = mvebu_pcie_powerup(port);
if (ret < 0)
continue;
port->base = mvebu_pcie_map_registers(pdev, child, port);
if (IS_ERR(port->base)) {
dev_err(dev, "%s: cannot map registers\n", port->name);
port->base = NULL;
mvebu_pcie_powerdown(port);
continue;
}
ret = mvebu_pci_bridge_emul_init(port);
if (ret < 0) {
dev_err(dev, "%s: cannot init emulated bridge\n",
port->name);
devm_iounmap(dev, port->base);
port->base = NULL;
mvebu_pcie_powerdown(port);
continue;
}
if (irq > 0) {
ret = mvebu_pcie_init_irq_domain(port);
if (ret) {
dev_err(dev, "%s: cannot init irq domain\n",
port->name);
pci_bridge_emul_cleanup(&port->bridge);
devm_iounmap(dev, port->base);
port->base = NULL;
mvebu_pcie_powerdown(port);
continue;
}
irq_set_chained_handler_and_data(irq,
mvebu_pcie_irq_handler,
port);
}
/*
* PCIe topology exported by mvebu hw is quite complicated. In
* reality has something like N fully independent host bridges
* where each host bridge has one PCIe Root Port (which acts as
* PCI Bridge device). Each host bridge has its own independent
* internal registers, independent access to PCI config space,
* independent interrupt lines, independent window and memory
* access configuration. But additionally there is some kind of
* peer-to-peer support between PCIe devices behind different
* host bridges limited just to forwarding of memory and I/O
* transactions (forwarding of error messages and config cycles
* is not supported). So we could say there are N independent
* PCIe Root Complexes.
*
* For this kind of setup DT should have been structured into
* N independent PCIe controllers / host bridges. But instead
* structure in past was defined to put PCIe Root Ports of all
* host bridges into one bus zero, like in classic multi-port
* Root Complex setup with just one host bridge.
*
* This means that pci-mvebu.c driver provides "virtual" bus 0
* on which registers all PCIe Root Ports (PCI Bridge devices)
* specified in DT by their BDF addresses and virtually routes
* PCI config access of each PCI bridge device to specific PCIe
* host bridge.
*
* Normally PCI Bridge should choose between Type 0 and Type 1
* config requests based on primary and secondary bus numbers
* configured on the bridge itself. But because mvebu PCI Bridge
* does not have registers for primary and secondary bus numbers
* in its config space, it determinates type of config requests
* via its own custom way.
*
* There are two options how mvebu determinate type of config
* request.
*
* 1. If Secondary Bus Number Enable bit is not set or is not
* available (applies for pre-XP PCIe controllers) then Type 0
* is used if target bus number equals Local Bus Number (bits
* [15:8] in register 0x1a04) and target device number differs
* from Local Device Number (bits [20:16] in register 0x1a04).
* Type 1 is used if target bus number differs from Local Bus
* Number. And when target bus number equals Local Bus Number
* and target device equals Local Device Number then request is
* routed to Local PCI Bridge (PCIe Root Port).
*
* 2. If Secondary Bus Number Enable bit is set (bit 7 in
* register 0x1a2c) then mvebu hw determinate type of config
* request like compliant PCI Bridge based on primary bus number
* which is configured via Local Bus Number (bits [15:8] in
* register 0x1a04) and secondary bus number which is configured
* via Secondary Bus Number (bits [7:0] in register 0x1a2c).
* Local PCI Bridge (PCIe Root Port) is available on primary bus
* as device with Local Device Number (bits [20:16] in register
* 0x1a04).
*
* Secondary Bus Number Enable bit is disabled by default and
* option 2. is not available on pre-XP PCIe controllers. Hence
* this driver always use option 1.
*
* Basically it means that primary and secondary buses shares
* one virtual number configured via Local Bus Number bits and
* Local Device Number bits determinates if accessing primary
* or secondary bus. Set Local Device Number to 1 and redirect
* all writes of PCI Bridge Secondary Bus Number register to
* Local Bus Number (bits [15:8] in register 0x1a04).
*
* So when accessing devices on buses behind secondary bus
* number it would work correctly. And also when accessing
* device 0 at secondary bus number via config space would be
* correctly routed to secondary bus. Due to issues described
* in mvebu_pcie_setup_hw(), PCI Bridges at primary bus (zero)
* are not accessed directly via PCI config space but rarher
* indirectly via kernel emulated PCI bridge driver.
*/
mvebu_pcie_setup_hw(port);
mvebu_pcie_set_local_dev_nr(port, 1);
mvebu_pcie_set_local_bus_nr(port, 0);
}
bridge->sysdata = pcie;
bridge->ops = &mvebu_pcie_ops;
bridge->child_ops = &mvebu_pcie_child_ops;
bridge->align_resource = mvebu_pcie_align_resource;
bridge->map_irq = mvebu_pcie_map_irq;
return pci_host_probe(bridge);
}
static void mvebu_pcie_remove(struct platform_device *pdev)
{
struct mvebu_pcie *pcie = platform_get_drvdata(pdev);
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
u32 cmd, sspl;
int i;
/* Remove PCI bus with all devices. */
pci_lock_rescan_remove();
pci_stop_root_bus(bridge->bus);
pci_remove_root_bus(bridge->bus);
pci_unlock_rescan_remove();
for (i = 0; i < pcie->nports; i++) {
struct mvebu_pcie_port *port = &pcie->ports[i];
int irq = port->intx_irq;
if (!port->base)
continue;
/* Disable Root Bridge I/O space, memory space and bus mastering. */
cmd = mvebu_readl(port, PCIE_CMD_OFF);
cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
mvebu_writel(port, cmd, PCIE_CMD_OFF);
/* Mask all interrupt sources. */
mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF);
/* Clear all interrupt causes. */
mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF);
if (irq > 0)
irq_set_chained_handler_and_data(irq, NULL, NULL);
/* Remove IRQ domains. */
if (port->intx_irq_domain)
irq_domain_remove(port->intx_irq_domain);
/* Free config space for emulated root bridge. */
pci_bridge_emul_cleanup(&port->bridge);
/* Disable sending Set_Slot_Power_Limit PCIe Message. */
sspl = mvebu_readl(port, PCIE_SSPL_OFF);
sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE);
mvebu_writel(port, sspl, PCIE_SSPL_OFF);
/* Disable and clear BARs and windows. */
mvebu_pcie_disable_wins(port);
/* Delete PCIe IO and MEM windows. */
if (port->iowin.size)
mvebu_pcie_del_windows(port, port->iowin.base, port->iowin.size);
if (port->memwin.size)
mvebu_pcie_del_windows(port, port->memwin.base, port->memwin.size);
/* Power down card and disable clocks. Must be the last step. */
mvebu_pcie_powerdown(port);
}
}
static const struct of_device_id mvebu_pcie_of_match_table[] = {
{ .compatible = "marvell,armada-xp-pcie", },
{ .compatible = "marvell,armada-370-pcie", },
{ .compatible = "marvell,dove-pcie", },
{ .compatible = "marvell,kirkwood-pcie", },
{},
};
static const struct dev_pm_ops mvebu_pcie_pm_ops = {
NOIRQ_SYSTEM_SLEEP_PM_OPS(mvebu_pcie_suspend, mvebu_pcie_resume)
};
static struct platform_driver mvebu_pcie_driver = {
.driver = {
.name = "mvebu-pcie",
.of_match_table = mvebu_pcie_of_match_table,
.pm = &mvebu_pcie_pm_ops,
},
.probe = mvebu_pcie_probe,
.remove_new = mvebu_pcie_remove,
};
module_platform_driver(mvebu_pcie_driver);
MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@bootlin.com>");
MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
MODULE_DESCRIPTION("Marvell EBU PCIe controller");
MODULE_LICENSE("GPL v2");
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