Commit Graph

8292 Commits

Author SHA1 Message Date
Jiri Slaby (SUSE)
0c8414a682 tty: vt: remove char32_t typedef
It boils down to uint32_t, so use u32 directly, instead. This makes the
code more obvious.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230112080136.4929-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:06:42 +01:00
Jiri Slaby (SUSE)
4ba77bfbad tty: vt: use sizeof(*variable) where possible
Instead of sizeof(type), use sizeof(*variable) which is preferred. We
are going to remove the unicode's char32_t typedef, so this makes the
switch easier.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230112080136.4929-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:06:42 +01:00
Jiri Slaby (SUSE)
70caeac76d tty: vt: remove reference to undefined NO_VC_UNI_SCREEN
NO_VC_UNI_SCREEN is defined nowhere. Remove the last reference to it.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230112080136.4929-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:06:41 +01:00
Jiri Slaby (SUSE)
3b140fbbbb tty: vt: drop get_vc_uniscr()
Its definition depends on the NO_VC_UNI_SCREEN macro. But that is never
defined, so remove all this completely. I.e. expand the macro to
vc->vc_uni_screen everywhere.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230112080136.4929-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:06:41 +01:00
Jiri Slaby (SUSE)
3831c2a454 tty: vt: remove vc_uniscr_debug_check()
VC_UNI_SCREEN_DEBUG is always defined as 0, so this code is never
executed. Drop it along with VC_UNI_SCREEN_DEBUG.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230112080136.4929-1-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:06:41 +01:00
Nate Drude
885692ae3c tty: serial: fsl_lpuart: increase maximum uart_nr to eight
Some SoCs like the i.MX93 have aliases for up to eight UARTs, see:
https://github.com/torvalds/linux/blob/v6.1/arch/arm64/boot/dts/freescale/imx93.dtsi#L31-L38

Increase UART_NR from 6 to 8 to support lpuart7 and lpuart8 and avoid
initialization failures like the following:

[    0.837146] fsl-lpuart 42690000.serial: serial6 out of range
[    0.842814] fsl-lpuart: probe of 42690000.serial failed with error -22

Signed-off-by: Nate Drude <nate.d@variscite.com>
Reviewed-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221222145634.2217793-1-nate.d@variscite.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:05:41 +01:00
Sherry Sun
509597ebca tty: serial: imx: disable the break condition when shutdown the uart port
The comment in imx_uart_shutdown() says to disable the break condition,
but it doesn't actually do that, here fix this by disabling UCR1_SNDBRK
when closing the uart port like other uart drivers do.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221214031137.28815-4-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:05:37 +01:00
Sherry Sun
10929eac41 tty: serial: fsl_lpuart: disable the break condition when shutdown the uart port
Need to disable the break condition for lpuart driver when closing
the uart port like other uart drivers do.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221214031137.28815-3-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:05:36 +01:00
Sherry Sun
c4c81db5cf tty: serial: fsl_lpuart: disable the CTS when send break signal
LPUART IP has a bug that it treats the CTS as higher priority than the
break signal, which cause the break signal sending through UARTCTRL_SBK
may impacted by the CTS input if the HW flow control is enabled.

Add this workaround patch to fix the IP bug, we can disable CTS before
asserting SBK to avoid any interference from CTS, and re-enable it when
break off.

Such as for the bluetooth chip power save feature, host can let the BT
chip get into sleep state by sending a UART break signal, and wake it up
by turning off the UART break. If the BT chip enters the sleep mode
successfully, it will pull up the CTS line, if the BT chip is woken up,
it will pull down the CTS line. If without this workaround patch, the
UART TX pin cannot send the break signal successfully as it affected by
the BT CTS pin. After adding this patch, the BT power save feature can
work well.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221214031137.28815-2-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:05:36 +01:00
Sherry Sun
4029dfc034 tty: serial: fsl_lpuart: clear LPUART Status Register in lpuart32_shutdown()
The LPUART Status Register needs to be cleared when closing the uart
port to get a clean environment when reopening the uart.

Fixes: 380c966c09 ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221125101953.18753-4-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:05:33 +01:00
Sherry Sun
1d4bd0e4ae tty: serial: fsl_lpuart: disable Rx/Tx DMA in lpuart32_shutdown()
UARTBAUD_RDMAE and UARTBAUD_TDMAE are enabled in lpuart32_startup(), but
lpuart32_shutdown() not disable them, only free the dma ring buffer and
release the dma channels, so here disable the Rx/Tx DMA first in
lpuart32_shutdown().

Fixes: 42b68768e5 ("serial: fsl_lpuart: DMA support for 32-bit variant")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221125101953.18753-3-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:05:33 +01:00
Sherry Sun
e1d91dda0b tty: serial: fsl_lpuart: only enable Idle Line Interrupt for non-dma case
For the lpuart driver, the Idle Line Interrupt Enable now is only needed
for the CPU mode, so enable the UARTCTRL_ILIE at the correct place, and
clear it when shutdown.

Also need to configure the suitable UARTCTRL_IDLECFG, now the value is
0x7, represent 128 idle characters will trigger the Idle Line Interrupt.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221125101953.18753-2-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:05:33 +01:00
Sven Schnelle
7370a25f93 tty/vt: prevent registration of console with invalid number
If a user specifies an invalid console like 'console=tty3000',
the vt driver should prevent setting up a vt entry for that.

Suggested-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Link: https://lore.kernel.org/r/20221209112737.3222509-3-svens@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:04:56 +01:00
Sven Schnelle
db4df8e9d7 tty: fix out-of-bounds access in tty_driver_lookup_tty()
When specifying an invalid console= device like console=tty3270,
tty_driver_lookup_tty() returns the tty struct without checking
whether index is a valid number.

To reproduce:

qemu-system-x86_64 -enable-kvm -nographic -serial mon:stdio \
-kernel ../linux-build-x86/arch/x86/boot/bzImage \
-append "console=ttyS0 console=tty3270"

This crashes with:

[    0.770599] BUG: kernel NULL pointer dereference, address: 00000000000000ef
[    0.771265] #PF: supervisor read access in kernel mode
[    0.771773] #PF: error_code(0x0000) - not-present page
[    0.772609] Oops: 0000 [#1] PREEMPT SMP PTI
[    0.774878] RIP: 0010:tty_open+0x268/0x6f0
[    0.784013]  chrdev_open+0xbd/0x230
[    0.784444]  ? cdev_device_add+0x80/0x80
[    0.784920]  do_dentry_open+0x1e0/0x410
[    0.785389]  path_openat+0xca9/0x1050
[    0.785813]  do_filp_open+0xaa/0x150
[    0.786240]  file_open_name+0x133/0x1b0
[    0.786746]  filp_open+0x27/0x50
[    0.787244]  console_on_rootfs+0x14/0x4d
[    0.787800]  kernel_init_freeable+0x1e4/0x20d
[    0.788383]  ? rest_init+0xc0/0xc0
[    0.788881]  kernel_init+0x11/0x120
[    0.789356]  ret_from_fork+0x22/0x30

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221209112737.3222509-2-svens@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:04:56 +01:00
Ilpo Järvinen
8573b2ebce serial: 8250_early: Convert literals to use defines
Use existing defines for the serial register values in 8250_early.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221125130509.8482-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:01:20 +01:00
Ilpo Järvinen
afd216ca17 serial: 8250: Define IIR 64 byte bit & cleanup related code
16750 indicates 64 bytes FIFO with a IIR bit. Add define for it and
make related code more obvious.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221125130509.8482-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:01:20 +01:00
Ilpo Järvinen
3398cc4f2b serial: 8250: Add IIR FIFOs enabled field properly
Don't use magic literals & comments but define a real field instead
for UART_IIR_FIFO_ENABLED and name also the values.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221125130509.8482-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:01:20 +01:00
Ilpo Järvinen
67a9aee781 serial: 8250: Cleanup MCR literals
Use proper names from MCR bits.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221125130509.8482-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:01:20 +01:00
Ilpo Järvinen
d9c1d3cbde serial: 8250: Name MSR literals
Add UART_MSR_STATUS_BITS for CD, RI, DSR & CTS. Use names for the
literal.

Don't make the define for combined flags part of UAPI.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221125130509.8482-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:01:19 +01:00
Ilpo Järvinen
ef460db2a7 serial: 8250: Use defined IER bits
Instead of literal 0x0f, add a define for enabling all IER bits the
8250 driver is interested in.

Don't make the define for combined flags part of UAPI.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221125130509.8482-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 15:01:19 +01:00
Jean Delvare
98a59cd26e serial: liteuart: drop obsolete dependency on COMPILE_TEST
Since commit 0166dc11be ("of: make CONFIG_OF user selectable"), it
is possible to test-build any driver which depends on OF on any
architecture by explicitly selecting OF. Therefore depending on
COMPILE_TEST as an alternative is no longer needed.

It is actually better to always build such drivers with OF enabled,
so that the test builds are closer to how each driver will actually be
built on its intended target. Building them without OF may not test
much as the compiler will optimize out potentially large parts of the
code. In the worst case, this could even pop false positive warnings.
Dropping COMPILE_TEST here improves the quality of our testing and
avoids wasting time on non-existent issues.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Karol Gugala <kgugala@antmicro.com>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Cc: Gabriel Somlo <gsomlo@gmail.com>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Gabriel Somlo <gsomlo@gmail.com>
Link: https://lore.kernel.org/r/20221125142756.3e51a28d@endymion.delvare
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:55 +01:00
Gabriel Somlo
f1c6c8b1b4 serial: liteuart: move polling putchar() function
The polling liteuart_putchar() function is only called from methods
conditionally enabled by CONFIG_SERIAL_LITEUART_CONSOLE. Move its
definition closer to the console code where it is dependent on the
same config option.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-15-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:41 +01:00
Gabriel Somlo
01a305a366 serial: liteuart: add IRQ support for the TX path
Switch the TX path to IRQ-driven operation, while maintaining support
for polling mode via the poll timer.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-14-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:41 +01:00
Gabriel Somlo
5602cf99dc serial: liteuart: add IRQ support for the RX path
Add support for IRQ-driven RX. Support for the TX path will be added
in a separate commit.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-13-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
7121d86eff serial: liteuart: move function definitions
Move definitions for liteuart_[stop|start]_tx(), liteuart_stop_rx(),
and liteuart_putchar() to a more convenient location in preparation
for adding IRQ support. This patch contains no functional changes.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-12-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
5dcceabe8e serial: liteuart: separate rx loop from poll timer
Convert the rx loop into its own dedicated function, and (for now)
call it from the poll timer. This is in preparation for adding irq
support to the receive path.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-11-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
a774aa4580 serial: liteuart: clean up rx loop variables
The `status` variable will always be `1` when passed into the call
to `uart_insert_char()`, so it can be eliminated altogether.

Use `u8` as the type for `ch`, as it matches the return type of
the `litex_read8()` call which produces its value.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-10-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
ca538cc727 serial: liteuart: simplify passing of uart_insert_char() flag
Simply provide the hard-coded TTY_NORMAL flag to uart_insert_char()
directly -- no need to dedicate a variable for that exclusive purpose.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-9-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
771268843c serial: liteuart: rx loop should only ack rx events
While receiving characters, it is necessary to acknowledge each one
by writing to the EV_PENDING register's EV_RX bit. Ensure we do not
also gratuitously set the EV_TX bit in the process.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-8-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
2ee91d42bf serial: liteuart: move tty_flip_buffer_push() out of rx loop
Calling tty_flip_buffer_push() for each individual received character
is overkill. Move it out of the rx loop, and only call it once per
set of characters received together.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-7-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
b9f5a18a9d serial: liteuart: minor style fix in liteuart_init()
Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-6-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
7378beacbb serial: liteuart: don't set unused port fields
Remove regshift and iobase port fields, since they are unused
by the driver.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-5-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
380596228d serial: liteuart: remove unused uart_ops stubs
Remove stub uart_ops methods that are not called unconditionally
from serial_core.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-4-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
5996b2e338 serial: liteuart: use bit number macros
Replace magic bit constants (e.g., 1, 2, 4) with BIT(x) expressions.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-3-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:40 +01:00
Gabriel Somlo
2696216bec serial: liteuart: use KBUILD_MODNAME as driver name
Replace hard-coded instances of "liteuart" with KBUILD_MODNAME.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-2-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:59:39 +01:00
Bin Meng
359fb3f870 serial: Rename earlycon semihost driver
Now that earlycon semihost driver works on RISC-V too, let's use a
much more generic name for the driver.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Tested-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20221209150437.795918-4-bmeng@tinylab.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:58:19 +01:00
Bin Meng
db5489f4be riscv: Implement semihost.h for earlycon semihost driver
Per RISC-V semihosting spec [1], implement semihost.h for the existing
Arm semihosting earlycon driver to work on RISC-V.

Link: https://github.com/riscv/riscv-semihosting-spec/blob/main/riscv-semihosting-spec.adoc [1]

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Tested-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20221209150437.795918-3-bmeng@tinylab.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:58:19 +01:00
Bin Meng
8890717526 serial: earlycon-arm-semihost: Move smh_putc() variants in respective arch's semihost.h
Move smh_putc() variants in respective arch/*/include/asm/semihost.h,
in preparation to add RISC-V support.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Tested-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20221209150437.795918-2-bmeng@tinylab.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:58:19 +01:00
Ricardo Ribalda
374b30f27f earlycon: Let users set the clock frequency
Some platforms, namely AMD Picasso, use non standard uart clocks (48M),
witch makes it impossible to use with earlycon.

Let the user select its own frequency.

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123-serial-clk-v3-1-49c516980ae0@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19 14:56:44 +01:00
Linus Torvalds
bad8c4a850 xen: branch for v6.2-rc4
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Merge tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - two cleanup patches

 - a fix of a memory leak in the Xen pvfront driver

 - a fix of a locking issue in the Xen hypervisor console driver

* tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/pvcalls: free active map buffer on pvcalls_front_free_map
  hvc/xen: lock console list traversal
  x86/xen: Remove the unused function p2m_index()
  xen: make remove callback of xen driver void returned
2023-01-12 17:02:20 -06:00
Roger Pau Monne
c0dccad87c hvc/xen: lock console list traversal
The currently lockless access to the xen console list in
vtermno_to_xencons() is incorrect, as additions and removals from the
list can happen anytime, and as such the traversal of the list to get
the private console data for a given termno needs to happen with the
lock held.  Note users that modify the list already do so with the
lock taken.

Adjust current lock takers to use the _irq{save,restore} helpers,
since the context in which vtermno_to_xencons() is called can have
interrupts disabled.  Use the _irq{save,restore} set of helpers to
switch the current callers to disable interrupts in the locked region.
I haven't checked if existing users could instead use the _irq
variant, as I think it's safer to use _irq{save,restore} upfront.

While there switch from using list_for_each_entry_safe to
list_for_each_entry: the current entry cursor won't be removed as
part of the code in the loop body, so using the _safe variant is
pointless.

Fixes: 02e19f9c7c ('hvc_xen: implement multiconsole support')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/20221130163611.14686-1-roger.pau@citrix.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-01-09 07:59:12 +01:00
Steven Rostedt (Google)
292a089d78 treewide: Convert del_timer*() to timer_shutdown*()
Due to several bugs caused by timers being re-armed after they are
shutdown and just before they are freed, a new state of timers was added
called "shutdown".  After a timer is set to this state, then it can no
longer be re-armed.

The following script was run to find all the trivial locations where
del_timer() or del_timer_sync() is called in the same function that the
object holding the timer is freed.  It also ignores any locations where
the timer->function is modified between the del_timer*() and the free(),
as that is not considered a "trivial" case.

This was created by using a coccinelle script and the following
commands:

    $ cat timer.cocci
    @@
    expression ptr, slab;
    identifier timer, rfield;
    @@
    (
    -       del_timer(&ptr->timer);
    +       timer_shutdown(&ptr->timer);
    |
    -       del_timer_sync(&ptr->timer);
    +       timer_shutdown_sync(&ptr->timer);
    )
      ... when strict
          when != ptr->timer
    (
            kfree_rcu(ptr, rfield);
    |
            kmem_cache_free(slab, ptr);
    |
            kfree(ptr);
    )

    $ spatch timer.cocci . > /tmp/t.patch
    $ patch -p1 < /tmp/t.patch

Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ]
Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ]
Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-25 13:38:09 -08:00
Linus Torvalds
71a7507afb Driver Core changes for 6.2-rc1
Here is the set of driver core and kernfs changes for 6.2-rc1.
 
 The "big" change in here is the addition of a new macro,
 container_of_const() that will preserve the "const-ness" of a pointer
 passed into it.
 
 The "problem" of the current container_of() macro is that if you pass in
 a "const *", out of it can comes a non-const pointer unless you
 specifically ask for it.  For many usages, we want to preserve the
 "const" attribute by using the same call.  For a specific example, this
 series changes the kobj_to_dev() macro to use it, allowing it to be used
 no matter what the const value is.  This prevents every subsystem from
 having to declare 2 different individual macros (i.e.
 kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
 the const value at build time, which having 2 macros would not do
 either.
 
 The driver for all of this have been discussions with the Rust kernel
 developers as to how to properly mark driver core, and kobject, objects
 as being "non-mutable".  The changes to the kobject and driver core in
 this pull request are the result of that, as there are lots of paths
 where kobjects and device pointers are not modified at all, so marking
 them as "const" allows the compiler to enforce this.
 
 So, a nice side affect of the Rust development effort has been already
 to clean up the driver core code to be more obvious about object rules.
 
 All of this has been bike-shedded in quite a lot of detail on lkml with
 different names and implementations resulting in the tiny version we
 have in here, much better than my original proposal.  Lots of subsystem
 maintainers have acked the changes as well.
 
 Other than this change, included in here are smaller stuff like:
   - kernfs fixes and updates to handle lock contention better
   - vmlinux.lds.h fixes and updates
   - sysfs and debugfs documentation updates
   - device property updates
 
 All of these have been in the linux-next tree for quite a while with no
 problems, OTHER than some merge issues with other trees that should be
 obvious when you hit them (block tree deletes a driver that this tree
 modifies, iommufd tree modifies code that this tree also touches).  If
 there are merge problems with these trees, please let me know.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the set of driver core and kernfs changes for 6.2-rc1.

  The "big" change in here is the addition of a new macro,
  container_of_const() that will preserve the "const-ness" of a pointer
  passed into it.

  The "problem" of the current container_of() macro is that if you pass
  in a "const *", out of it can comes a non-const pointer unless you
  specifically ask for it. For many usages, we want to preserve the
  "const" attribute by using the same call. For a specific example, this
  series changes the kobj_to_dev() macro to use it, allowing it to be
  used no matter what the const value is. This prevents every subsystem
  from having to declare 2 different individual macros (i.e.
  kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
  the const value at build time, which having 2 macros would not do
  either.

  The driver for all of this have been discussions with the Rust kernel
  developers as to how to properly mark driver core, and kobject,
  objects as being "non-mutable". The changes to the kobject and driver
  core in this pull request are the result of that, as there are lots of
  paths where kobjects and device pointers are not modified at all, so
  marking them as "const" allows the compiler to enforce this.

  So, a nice side affect of the Rust development effort has been already
  to clean up the driver core code to be more obvious about object
  rules.

  All of this has been bike-shedded in quite a lot of detail on lkml
  with different names and implementations resulting in the tiny version
  we have in here, much better than my original proposal. Lots of
  subsystem maintainers have acked the changes as well.

  Other than this change, included in here are smaller stuff like:

   - kernfs fixes and updates to handle lock contention better

   - vmlinux.lds.h fixes and updates

   - sysfs and debugfs documentation updates

   - device property updates

  All of these have been in the linux-next tree for quite a while with
  no problems"

* tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits)
  device property: Fix documentation for fwnode_get_next_parent()
  firmware_loader: fix up to_fw_sysfs() to preserve const
  usb.h: take advantage of container_of_const()
  device.h: move kobj_to_dev() to use container_of_const()
  container_of: add container_of_const() that preserves const-ness of the pointer
  driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion.
  driver core: fix up missed scsi/cxlflash class.devnode() conversion.
  driver core: fix up some missing class.devnode() conversions.
  driver core: make struct class.devnode() take a const *
  driver core: make struct class.dev_uevent() take a const *
  cacheinfo: Remove of_node_put() for fw_token
  device property: Add a blank line in Kconfig of tests
  device property: Rename goto label to be more precise
  device property: Move PROPERTY_ENTRY_BOOL() a bit down
  device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*()
  kernfs: fix all kernel-doc warnings and multiple typos
  driver core: pass a const * into of_device_uevent()
  kobject: kset_uevent_ops: make name() callback take a const *
  kobject: kset_uevent_ops: make filter() callback take a const *
  kobject: make kobject_namespace take a const *
  ...
2022-12-16 03:54:54 -08:00
Linus Torvalds
dd6f9b17cd TTY/Serial driver changes for 6.2-rc1
Here is the "big" set of tty/serial driver changes for 6.2-rc1.
 
 As in previous kernel releases, nothing big here at all, just some small
 incremental serial/tty layer cleanups and some individual driver
 additions and fixes.  Highlights are:
   - serial helper macros from Jiri Slaby to reduce the amount of
     duplicated code in serial drivers
   - api cleanups and consolidations from Ilpo Järvinen in lots of serial
     drivers
   - the usual set of n_gsm fixes from Daniel Starke as that code gets
     exercised more
   - TIOCSTI is finally able to be disabled if requested (security
     hardening feature from Kees Cook)
   - fsl_lpuart driver fixes and features added
   - other small serial driver additions and fixes
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the "big" set of tty/serial driver changes for 6.2-rc1.

  As in previous kernel releases, nothing big here at all, just some
  small incremental serial/tty layer cleanups and some individual driver
  additions and fixes. Highlights are:

   - serial helper macros from Jiri Slaby to reduce the amount of
     duplicated code in serial drivers

   - api cleanups and consolidations from Ilpo Järvinen in lots of
     serial drivers

   - the usual set of n_gsm fixes from Daniel Starke as that code gets
     exercised more

   - TIOCSTI is finally able to be disabled if requested (security
     hardening feature from Kees Cook)

   - fsl_lpuart driver fixes and features added

   - other small serial driver additions and fixes

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'tty-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (97 commits)
  serial: atmel: don't stop the transmitter when doing PIO
  serial: atmel: cleanup atmel_start+stop_tx()
  tty: serial: fsl_lpuart: switch to new dmaengine_terminate_* API
  serial: sunsab: Fix error handling in sunsab_init()
  serial: altera_uart: fix locking in polling mode
  serial: pch: Fix PCI device refcount leak in pch_request_dma()
  tty: serial: fsl_lpuart: Use pm_ptr() to avoid need to make pm __maybe_unused
  tty: serial: fsl_lpuart: Add runtime pm support
  tty: serial: fsl_lpuart: enable wakeup source for lpuart
  serdev: Replace poll loop by readx_poll_timeout() macro
  tty: synclink_gt: unwind actions in error path of net device open
  serial: stm32: move dma_request_chan() before clk_prepare_enable()
  dt-bindings: serial: xlnx,opb-uartlite: Drop 'contains' from 'xlnx,use-parity'
  serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle.
  serial: amba-pl011: avoid SBSA UART accessing DMACR register
  tty: serial: altera_jtaguart: remove struct altera_jtaguart
  tty: serial: altera_jtaguart: use uart_port::read_status_mask
  tty: serial: altera_jtaguart: remove unused altera_jtaguart::sigs
  tty: serial: altera_jtaguart: remove flag from altera_jtaguart_rx_chars()
  n_tty: Rename tail to old_tail in n_tty_read()
  ...
2022-12-16 03:31:56 -08:00
Dawei Li
7cffcade57 xen: make remove callback of xen driver void returned
Since commit fc7a6209d5 ("bus: Make remove callback return void")
forces bus_type::remove be void-returned, it doesn't make much sense for
any bus based driver implementing remove callbalk to return non-void to
its caller.

This change is for xen bus based drivers.

Acked-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Link: https://lore.kernel.org/r/TYCP286MB23238119AB4DF190997075C9CAE39@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-12-15 16:06:10 +01:00
Linus Torvalds
98d0052d0d printk changes for 6.2
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Merge tag 'printk-for-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk updates from Petr Mladek:

 - Add NMI-safe SRCU reader API. It uses atomic_inc() instead of
   this_cpu_inc() on strong load-store architectures.

 - Introduce new console_list_lock to synchronize a manipulation of the
   list of registered consoles and their flags.

   This is a first step in removing the big-kernel-lock-like behavior of
   console_lock(). This semaphore still serializes console->write()
   calbacks against:

      - each other. It primary prevents potential races between early
        and proper console drivers using the same device.

      - suspend()/resume() callbacks and init() operations in some
        drivers.

      - various other operations in the tty/vt and framebufer
        susbsystems. It is likely that console_lock() serializes even
        operations that are not directly conflicting with the
        console->write() callbacks here. This is the most complicated
        big-kernel-lock aspect of the console_lock() that will be hard
        to untangle.

 - Introduce new console_srcu lock that is used to safely iterate and
   access the registered console drivers under SRCU read lock.

   This is a prerequisite for introducing atomic console drivers and
   console kthreads. It will reduce the complexity of serialization
   against normal consoles and console_lock(). Also it should remove the
   risk of deadlock during critical situations, like Oops or panic, when
   only atomic consoles are registered.

 - Check whether the console is registered instead of enabled on many
   locations. It was a historical leftover.

 - Cleanly force a preferred console in xenfb code instead of a dirty
   hack.

 - A lot of code and comment clean ups and improvements.

* tag 'printk-for-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (47 commits)
  printk: htmldocs: add missing description
  tty: serial: sh-sci: use setup() callback for early console
  printk: relieve console_lock of list synchronization duties
  tty: serial: kgdboc: use console_list_lock to trap exit
  tty: serial: kgdboc: synchronize tty_find_polling_driver() and register_console()
  tty: serial: kgdboc: use console_list_lock for list traversal
  tty: serial: kgdboc: use srcu console list iterator
  proc: consoles: use console_list_lock for list iteration
  tty: tty_io: use console_list_lock for list synchronization
  printk, xen: fbfront: create/use safe function for forcing preferred
  netconsole: avoid CON_ENABLED misuse to track registration
  usb: early: xhci-dbc: use console_is_registered()
  tty: serial: xilinx_uartps: use console_is_registered()
  tty: serial: samsung_tty: use console_is_registered()
  tty: serial: pic32_uart: use console_is_registered()
  tty: serial: earlycon: use console_is_registered()
  tty: hvc: use console_is_registered()
  efi: earlycon: use console_is_registered()
  tty: nfcon: use console_is_registered()
  serial_core: replace uart_console_enabled() with uart_console_registered()
  ...
2022-12-12 09:01:36 -08:00
John Ogness
ff707dfd79 tty: serial: sh-sci: use setup() callback for early console
When setting up the early console, the setup() callback of the
regular console is used. It is called manually before registering
the early console instead of providing a setup() callback for the
early console. This is probably because the early setup needs a
different @options during the early stage.

The issue here is that the setup() callback is called without the
console_list_lock held and functions such as uart_set_options()
expect that.

Rather than manually calling the setup() function before registering,
provide an early console setup() callback that will use the different
early options. This ensures that the error checking, ordering, and
locking context when setting up the early console are correct.

Since this early console can only be registered via the earlyprintk=
parameter, the @options argument of the setup() callback will always
be NULL. Rather than simply ignoring the argument, add a WARN_ON()
to get our attention in case the setup() callback semantics should
change in the future.

Note that technically the current implementation works because it is
only used in early boot. And since the early console setup is
performed before registering, it cannot race with anything and thus
does not need any locking. However, longterm maintenance is easier
when drivers rely on the subsystem API rather than manually
implementing steps that could cause breakage in the future.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-41-john.ogness@linutronix.de
2022-12-02 11:25:02 +01:00
John Ogness
e2b3965228 tty: serial: kgdboc: use console_list_lock to trap exit
kgdboc_earlycon_init() uses the console_lock to ensure that no consoles
are unregistered until the kgdboc_earlycon is setup. The console_list_lock
should be used instead because list synchronization responsibility will
be removed from the console_lock in a later change.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-39-john.ogness@linutronix.de
2022-12-02 11:25:02 +01:00
John Ogness
6193bc9084 tty: serial: kgdboc: synchronize tty_find_polling_driver() and register_console()
Calling tty_find_polling_driver() can lead to uart_set_options() being
called (via the poll_init() callback of tty_operations) to configure the
uart. But uart_set_options() can also be called by register_console()
(via the setup() callback of console).

Take the console_list_lock to synchronize against register_console() and
also use it for console list traversal. This also ensures the console list
cannot change until the polling console has been chosen.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-38-john.ogness@linutronix.de
2022-12-02 11:25:02 +01:00
John Ogness
6685744369 tty: serial: kgdboc: use console_list_lock for list traversal
configure_kgdboc() uses the console_lock for console list iteration. Use
the console_list_lock instead because list synchronization responsibility
will be removed from the console_lock in a later change.

The SRCU iterator could have been used here, but a later change will
relocate the locking of the console_list_lock to also provide
synchronization against register_console().

Note, the console_lock is still needed to serialize the device()
callback with other console operations.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-37-john.ogness@linutronix.de
2022-12-02 11:25:02 +01:00