Commit Graph

7403 Commits

Author SHA1 Message Date
Linus Torvalds
bca21755b9 Merge tag 'acpi-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
 "These are usual ACPICA code updates (although there are more of them
  than in the last few releases), a noticeable EC driver update (which
  mostly consists of cleanups, though), the device enumeration quirks
  handling rework from Hans, some updates eliminating unnecessary CPU
  cache flushing in some places (processor idle and system-wide PM code)
  and a bunch of assorted cleanups and fixes.

  Specifics:

   - Update ACPICA code in the kernel to the 20211217 upstream release
     including the following changes:

      - iASL/Disassembler: Additional support for NHLT table (Bob
        Moore).
      - Change a return_ACPI_STATUS (AE_BAD_PARAMETER) (Bob Moore).
      - Fix a couple of warnings under MSVC (Bob Moore).
      - iASL: Add TDEL table to both compiler/disassembler (Bob Moore).
      - iASL/NHLT table: "Specific Data" field support (Bob Moore).
      - Use original data_table_region pointer for accesses (Jessica
        Clarke).
      - Use original pointer for virtual origin tables (Jessica Clarke).
      - Macros: Remove ACPI_PHYSADDR_TO_PTR (Jessica Clarke).
      - Avoid subobject buffer overflow when validating RSDP signature
        (Jessica Clarke).
      - iASL: Add suppport for AGDI table (Ilkka Koskinen).
      - Hardware: Do not flush CPU cache when entering S4 and S5 (Kirill
        A. Shutemov).
      - Expand the ACPI_ACCESS_ definitions (Mark Langsdorf).
      - Utilities: Avoid deleting the same object twice in a row (Rafael
        Wysocki).
      - Executer: Fix REFCLASS_REFOF case in acpi_ex_opcode_1A_0T_1R()
        (Rafael Wysocki).
      - Fix AEST Processor generic resource substructure data field byte
        length (Shuuichirou Ishii).
      - Fix wrong interpretation of PCC address (Sudeep Holla).
      - Add support for PCC Opregion special context data (Sudeep
        Holla).

   - Implement OperationRegion handler for PCC Type 3 subtype (Sudeep
     Holla).

   - Introduce acpi_fetch_acpi_dev() as a replacement for
     acpi_bus_get_device() and use it in the ACPI subsystem (Rafael
     Wysocki).

   - Avoid using _CID for device enumaration if _HID is missing or
     invalid (Rafael Wysocki).

   - Rework quirk handling during ACPI device enumeration and add some
     new quirks for known broken platforms (Hans de Goede).

   - Avoid unnecessary or redundant CPU cache flushing during system PM
     transitions (Kirill A. Shutemov).

   - Add PM debug messages related to power resources (Rafael Wysocki).

   - Fix kernel-doc comment in the PCI host bridge ACPI driver (Yang
     Li).

   - Rework flushing of EC work while suspended to idle and clean up the
     handling of events in the ACPI EC driver (Rafael Wysocki).

   - Prohibit ec_sys module parameter write_support from being used when
     the system is locked down (Hans de Goede).

   - Make the ACPI processor thermal driver use cpufreq_cpu_get() to
     check for presence of cpufreq policy (Manfred Spraul).

   - Avoid unnecessary CPU cache flushing in the ACPI processor idle
     driver (Kirill A. Shutemov).

   - Replace kernel.h with the necessary inclusions in the ACPI
     processor driver (Andy Shevchenko).

   - Use swap() instead of open coding it in the ACPI processor idle
     driver (Guo Zhengkui).

   - Fix the handling of defective LPAT in the ACPI xpower PMIC driver
     and clean up some definitions of PMIC data structures (Hans de
     Goede).

   - Fix outdated comment in the ACPI DPTF driver (Sumeet Pawnikar).

   - Add AEST to the list of known ACPI table signatures (Shuuichirou
     Ishii).

   - Make ACPI NUMA code take hotpluggable memblocks into account when
     CONFIG_MEMORY_HOTPLUG is not set (Vitaly Kuznetsov).

   - Use default_groups in kobj_type in the ACPI sysfs code (Greg
     Kroah-Hartman).

   - Rearrange _CPC structure documentation (Andy Shevchenko).

   - Drop an always true check from the ACPI thermal driver (Adam
     Borowski).

   - Add new "not charging" quirk for Lenovo ThinkPads to the ACPI
     battery driver (Thomas Weißschuh)"

* tag 'acpi-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (64 commits)
  ACPI: PCC: Implement OperationRegion handler for the PCC Type 3 subtype
  ACPI / x86: Skip AC and battery devices on x86 Android tablets with broken DSDTs
  ACPI / x86: Introduce an acpi_quirk_skip_acpi_ac_and_battery() helper
  ACPI: processor: thermal: avoid cpufreq_get_policy()
  serdev: Do not instantiate serdevs on boards with known bogus DSDT entries
  i2c: acpi: Do not instantiate I2C-clients on boards with known bogus DSDT entries
  ACPI / x86: Add acpi_quirk_skip_[i2c_client|serdev]_enumeration() helpers
  ACPI: scan: Create platform device for BCM4752 and LNV4752 ACPI nodes
  PCI/ACPI: Fix acpi_pci_osc_control_set() kernel-doc comment
  ACPI: battery: Add the ThinkPad "Not Charging" quirk
  ACPI: sysfs: use default_groups in kobj_type
  ACPICA: Update version to 20211217
  ACPICA: iASL/NHLT table: "Specific Data" field support
  ACPICA: iASL: Add suppport for AGDI table
  ACPICA: iASL: Add TDEL table to both compiler/disassembler
  ACPICA: Fixed a couple of warnings under MSVC
  ACPICA: Change a return_ACPI_STATUS (AE_BAD_PARAMETER)
  ACPICA: Hardware: Do not flush CPU cache when entering S4 and S5
  ACPICA: Add support for PCC Opregion special context data
  ACPICA: Fix wrong interpretation of PCC address
  ...
2022-01-10 20:26:56 -08:00
Linus Torvalds
bb4ed26e7e Merge tag 'newsoc-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull RISC-V SoC updates from Arnd Bergmann:
 "Add support for StarFive JH7100 RISC-V SoC

  This adds support for the StarFive JH7100, including the necessary
  device drivers and DT files for the BeagleV Starlight prototype board,
  with additional boards to be added later. This SoC promises to be the
  first usable low-cost platform for RISC-V.

  I've taken this through the SoC tree in the anticipation of adding a
  few other Arm based SoCs as well, but those did not pass the review in
  time, so it's only this one"

* tag 'newsoc-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  reset: starfive-jh7100: Fix 32bit compilation
  RISC-V: Add BeagleV Starlight Beta device tree
  RISC-V: Add initial StarFive JH7100 device tree
  serial: 8250_dw: Add StarFive JH7100 quirk
  dt-bindings: serial: snps-dw-apb-uart: Add JH7100 uarts
  pinctrl: starfive: Add pinctrl driver for StarFive SoCs
  dt-bindings: pinctrl: Add StarFive JH7100 bindings
  dt-bindings: pinctrl: Add StarFive pinctrl definitions
  reset: starfive-jh7100: Add StarFive JH7100 reset driver
  dt-bindings: reset: Add Starfive JH7100 reset bindings
  dt-bindings: reset: Add StarFive JH7100 reset definitions
  clk: starfive: Add JH7100 clock generator driver
  dt-bindings: clock: starfive: Add JH7100 bindings
  dt-bindings: clock: starfive: Add JH7100 clock definitions
  dt-bindings: interrupt-controller: Add StarFive JH7100 plic
  dt-bindings: timer: Add StarFive JH7100 clint
  RISC-V: Add StarFive SoC Kconfig option
2022-01-10 08:32:37 -08:00
Rafael J. Wysocki
b659ea768a Merge branches 'acpi-scan', 'acpi-pm', 'acpi-power' and 'acpi-pci'
Merge ACPI device enumeration updates, ACPI power management updates
and PCI host bridge ACPI driver updates for 5.17-rc1:

 - Introduce acpi_fetch_acpi_dev() as a replacement for
   acpi_bus_get_device() and use it in the ACPI subsystem (Rafael
   Wysocki).

 - Avoid using _CID for device enumaration if _HID is missing or
   invalid (Rafael Wysocki).

 - Rework quirk handling during ACPI device enumeration and add some
   new quirks for known broken platforms (Hans de Goede).

 - Avoid unnecessary or redundant CPU cache flushing during system
   PM transitions (Kirill A. Shutemov).

 - Add PM debug messages related to power resources (Rafael Wysocki).

 - Fix kernel-doc comment in the PCI host bridge ACPI driver (Yang Li).

* acpi-scan:
  serdev: Do not instantiate serdevs on boards with known bogus DSDT entries
  i2c: acpi: Do not instantiate I2C-clients on boards with known bogus DSDT entries
  ACPI / x86: Add acpi_quirk_skip_[i2c_client|serdev]_enumeration() helpers
  ACPI: scan: Create platform device for BCM4752 and LNV4752 ACPI nodes
  ACPI: Use acpi_fetch_acpi_dev() instead of acpi_bus_get_device()
  ACPI: scan: Introduce acpi_fetch_acpi_dev()
  ACPI: scan: Do not add device IDs from _CID if _HID is not valid

* acpi-pm:
  ACPI: PM: Remove redundant cache flushing
  ACPI: PM: Avoid CPU cache flush when entering S4

* acpi-power:
  ACPI: PM: Emit debug messages when enabling/disabling wakeup power

* acpi-pci:
  PCI/ACPI: Fix acpi_pci_osc_control_set() kernel-doc comment
2022-01-10 16:48:27 +01:00
Hans de Goede
0890186a96 serdev: Do not instantiate serdevs on boards with known bogus DSDT entries
x86 ACPI devices which ship with only Android as their factory image use
older kernels which do not yet support ACPI serdev enumeration, as such
the serdev information in their ACPI tables is not reliable.

For example on the Asus ME176C tablet the serdev describing the Bluetooth
HCI points to the serdev_controller connected to the GPS and the other way
around.

Use the new acpi_quirk_skip_serdev_enumeration() helper to identify
known boards with this issue and then either abort adding the serdev
controller (creating a tty cdev instead) or only create the controller
leaving the instantation of the serdev itself up to platform code.

In the case where only the serdev controller is created the necessary
serdevs will instead be instantiated by the
drivers/platform/x86/x86-android-tablets.c kernel module.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-30 19:01:42 +01:00
Linus Torvalds
59b3f94488 Merge branch 'xsa' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Merge xen fixes from Juergen Gross:
 "Fixes for two issues related to Xen and malicious guests:

   - Guest can force the netback driver to hog large amounts of memory

   - Denial of Service in other guests due to event storms"

* 'xsa' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/netback: don't queue unlimited number of packages
  xen/netback: fix rx queue stall detection
  xen/console: harden hvc_xen against event channel storms
  xen/netfront: harden netfront against event channel storms
  xen/blkfront: harden blkfront against event channel storms
2021-12-20 07:42:21 -08:00
Emil Renner Berthing
b0ad20a3b6 serial: 8250_dw: Add StarFive JH7100 quirk
On the StarFive JH7100 RISC-V SoC the UART core clocks can't be set to
exactly 16 * 115200Hz and many other common bitrates. Trying this will
only result in a higher input clock, but low enough that the UART's
internal divisor can't come close enough to the baud rate target.
So rather than try to set the input clock it's better to skip the
clk_set_rate call and rely solely on the UART's internal divisor.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
2021-12-16 17:24:23 +01:00
Juergen Gross
fe415186b4 xen/console: harden hvc_xen against event channel storms
The Xen console driver is still vulnerable for an attack via excessive
number of events sent by the backend. Fix that by using a lateeoi event
channel.

For the normal domU initial console this requires the introduction of
bind_evtchn_to_irq_lateeoi() as there is no xenbus device available
at the time the event channel is bound to the irq.

As the decision whether an interrupt was spurious or not requires to
test for bytes having been read from the backend, move sending the
event into the if statement, as sending an event without having found
any bytes to be read is making no sense at all.

This is part of XSA-391

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
V2:
- slightly adapt spurious irq detection (Jan Beulich)
V3:
- fix spurious irq detection (Jan Beulich)
2021-12-16 08:24:08 +01:00
Ji-Ze Hong (Peter Hong)
6c33ff7288 serial: 8250_fintek: Fix garbled text for console
Commit fab8a02b73 ("serial: 8250_fintek: Enable high speed mode on Fintek F81866")
introduced support to use high baudrate with Fintek SuperIO UARTs. It'll
change clocksources when the UART probed.

But when user add kernel parameter "console=ttyS0,115200 console=tty0" to make
the UART as console output, the console will output garbled text after the
following kernel message.

[    3.681188] Serial: 8250/16550 driver, 32 ports, IRQ sharing enabled

The issue is occurs in following step:
	probe_setup_port() -> fintek_8250_goto_highspeed()

It change clocksource from 115200 to 921600 with wrong time, it should change
clocksource in set_termios() not in probed. The following 3 patches are
implemented change clocksource in fintek_8250_set_termios().

Commit 58178914ae ("serial: 8250_fintek: UART dynamic clocksource on Fintek F81216H")
Commit 195638b6d4 ("serial: 8250_fintek: UART dynamic clocksource on Fintek F81866")
Commit 423d9118c6 ("serial: 8250_fintek: Add F81966 Support")

Due to the high baud rate had implemented above 3 patches and the patch
Commit fab8a02b73 ("serial: 8250_fintek: Enable high speed mode on Fintek F81866")
is bugged, So this patch will remove it.

Fixes: fab8a02b73 ("serial: 8250_fintek: Enable high speed mode on Fintek F81866")
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Link: https://lore.kernel.org/r/20211215075835.2072-1-hpeter+linux_kernel@gmail.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-15 21:51:07 +01:00
Tetsuo Handa
1ee33b1ca2 tty: n_hdlc: make n_hdlc_tty_wakeup() asynchronous
syzbot is reporting that an unprivileged user who logged in from tty
console can crash the system using a reproducer shown below [1], for
n_hdlc_tty_wakeup() is synchronously calling n_hdlc_send_frames().

----------
  #include <sys/ioctl.h>
  #include <unistd.h>

  int main(int argc, char *argv[])
  {
    const int disc = 0xd;

    ioctl(1, TIOCSETD, &disc);
    while (1) {
      ioctl(1, TCXONC, 0);
      write(1, "", 1);
      ioctl(1, TCXONC, 1); /* Kernel panic - not syncing: scheduling while atomic */
    }
  }
----------

Linus suspected that "struct tty_ldisc"->ops->write_wakeup() must not
sleep, and Jiri confirmed it from include/linux/tty_ldisc.h. Thus, defer
n_hdlc_send_frames() from n_hdlc_tty_wakeup() to a WQ context like
net/nfc/nci/uart.c does.

Link: https://syzkaller.appspot.com/bug?extid=5f47a8cea6a12b77a876 [1]
Reported-by: syzbot <syzbot+5f47a8cea6a12b77a876@syzkaller.appspotmail.com>
Cc: stable <stable@vger.kernel.org>
Analyzed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Confirmed-by: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://lore.kernel.org/r/40de8b7e-a3be-4486-4e33-1b1d1da452f8@i-love.sakura.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-15 21:50:39 +01:00
Linus Torvalds
5163953950 Merge tag 'tty-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
 "Here are some small TTY and Serial driver fixes for 5.16-rc4 to
  resolve a number of reported problems.

  They include:

   - liteuart serial driver fixes

   - 8250_pci serial driver fixes for pericom devices

   - 8250 RTS line control fix while in RS-485 mode

   - tegra serial driver fix

   - msm_serial driver fix

   - pl011 serial driver new id

   - fsl_lpuart revert of broken change

   - 8250_bcm7271 serial driver fix

   - MAINTAINERS file update for rpmsg tty driver that came in 5.16-rc1

   - vgacon fix for reported problem

  All of these, except for the 8250_bcm7271 fix have been in linux-next
  with no reported problem. The 8250_bcm7271 fix was added to the tree
  on Friday so no chance to be linux-next yet. But it should be fine as
  the affected developers submitted it"

* tag 'tty-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250_bcm7271: UART errors after resuming from S2
  serial: 8250_pci: rewrite pericom_do_set_divisor()
  serial: 8250_pci: Fix ACCES entries in pci_serial_quirks array
  serial: 8250: Fix RTS modem control while in rs485 mode
  Revert "tty: serial: fsl_lpuart: drop earlycon entry for i.MX8QXP"
  serial: tegra: Change lower tolerance baud rate limit for tegra20 and tegra30
  serial: liteuart: relax compile-test dependencies
  serial: liteuart: fix minor-number leak on probe errors
  serial: liteuart: fix use-after-free and memleak on unbind
  serial: liteuart: Fix NULL pointer dereference in ->remove()
  vgacon: Propagate console boot parameters before calling `vc_resize'
  tty: serial: msm_serial: Deactivate RX DMA for polling support
  serial: pl011: Add ACPI SBSA UART match id
  serial: core: fix transmit-buffer reset and memleak
  MAINTAINERS: Add rpmsg tty driver maintainer
2021-12-05 09:13:20 -08:00
Al Cooper
9cabe26e65 serial: 8250_bcm7271: UART errors after resuming from S2
There is a small window in time during resume where the hardware
flow control signal RTS can be asserted (which allows a sender to
resume sending data to the UART) but the baud rate has not yet
been restored. This will cause corrupted data and FRAMING, OVERRUN
and BREAK errors. This is happening because the MCTRL register is
shadowed in uart_port struct and is later used during resume to set
the MCTRL register during both serial8250_do_startup() and
uart_resume_port(). Unfortunately, serial8250_do_startup()
happens before the UART baud rate is restored. The fix is to clear
the shadowed mctrl value at the end of suspend and restore it at the
end of resume.

Fixes: 41a469482d ("serial: 8250: Add new 8250-core based Broadcom STB driver")
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Link: https://lore.kernel.org/r/20211201201402.47446-1-alcooperx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-03 14:14:49 +01:00
Jay Dolan
bb1201d4b3 serial: 8250_pci: rewrite pericom_do_set_divisor()
Have pericom_do_set_divisor() use the uartclk instead of a hard coded
value to work with different speed crystals. Tested with 14.7456 and 24
MHz crystals.

Have pericom_do_set_divisor() always calculate the divisor rather than
call serial8250_do_set_divisor() for rates below baud_base.

Do not write registers or call serial8250_do_set_divisor() if valid
divisors could not be found.

Fixes: 6bf4e42f1d ("serial: 8250: Add support for higher baud rates to Pericom chips")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211122120604.3909-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:42:15 +01:00
Jay Dolan
c525c5d243 serial: 8250_pci: Fix ACCES entries in pci_serial_quirks array
Fix error in table for PCI_DEVICE_ID_ACCESIO_PCIE_ICM_4S that caused it
and PCI_DEVICE_ID_ACCESIO_PCIE_ICM232_4 to be missing their fourth port.

Fixes: 78d3820b9b ("serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211122120604.3909-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:42:10 +01:00
Lukas Wunner
f85e04503f serial: 8250: Fix RTS modem control while in rs485 mode
Commit f45709df77 ("serial: 8250: Don't touch RTS modem control while
in rs485 mode") sought to prevent user space from interfering with rs485
communication by ignoring a TIOCMSET ioctl() which changes RTS polarity.

It did so in serial8250_do_set_mctrl(), which turns out to be too deep
in the call stack:  When a uart_port is opened, RTS polarity is set by
the rs485-aware function uart_port_dtr_rts().  It calls down to
serial8250_do_set_mctrl() and that particular RTS polarity change should
*not* be ignored.

The user-visible result is that on 8250_omap ports which use rs485 with
inverse polarity (RTS bit in MCR register is 1 to receive, 0 to send),
a newly opened port initially sets up RTS for sending instead of
receiving.  That's because omap_8250_startup() sets the cached value
up->mcr to 0 and omap_8250_restore_regs() subsequently writes it to the
MCR register.  Due to the commit, serial8250_do_set_mctrl() preserves
that incorrect register value:

do_sys_openat2
  do_filp_open
    path_openat
      vfs_open
        do_dentry_open
	  chrdev_open
	    tty_open
	      uart_open
	        tty_port_open
		  uart_port_activate
		    uart_startup
		      uart_port_startup
		        serial8250_startup
			  omap_8250_startup # up->mcr = 0
			uart_change_speed
			  serial8250_set_termios
			    omap_8250_set_termios
			      omap_8250_restore_regs
			        serial8250_out_MCR # up->mcr written
		  tty_port_block_til_ready
		    uart_dtr_rts
		      uart_port_dtr_rts
		        serial8250_set_mctrl
			  omap8250_set_mctrl
			    serial8250_do_set_mctrl # mcr[1] = 1 ignored

Fix by intercepting RTS changes from user space in uart_tiocmset()
instead.

Link: https://lore.kernel.org/linux-serial/20211027111644.1996921-1-baocheng.su@siemens.com/
Fixes: f45709df77 ("serial: 8250: Don't touch RTS modem control while in rs485 mode")
Cc: Chao Zeng <chao.zeng@siemens.com>
Cc: stable@vger.kernel.org # v5.7+
Reported-by: Su Bao Cheng <baocheng.su@siemens.com>
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Tested-by: Su Bao Cheng <baocheng.su@siemens.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/21170e622a1aaf842a50b32146008b5374b3dd1d.1637596432.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:41:09 +01:00
Alexander Stein
4e9679738a Revert "tty: serial: fsl_lpuart: drop earlycon entry for i.MX8QXP"
Revert commit b4b844930f ("tty: serial: fsl_lpuart: drop earlycon entry
for i.MX8QXP"), because this breaks earlycon support on imx8qm/imx8qxp.
While it is true that for earlycon there is no difference between
i.MX8QXP and i.MX7ULP (for now at least), there are differences
regarding clocks and fixups for wakeup support. For that reason it was
deemed unacceptable to add the imx7ulp compatible to device tree in
order to get earlycon working again.

Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/20211124073109.805088-1-alexander.stein@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:27:44 +01:00
Patrik John
b40de7469e serial: tegra: Change lower tolerance baud rate limit for tegra20 and tegra30
The current implementation uses 0 as lower limit for the baud rate
tolerance for tegra20 and tegra30 chips which causes isses on UART
initialization as soon as baud rate clock is lower than required even
when within the standard UART tolerance of +/- 4%.

This fix aligns the implementation with the initial commit description
of +/- 4% tolerance for tegra chips other than tegra186 and
tegra194.

Fixes: d781ec21ba ("serial: tegra: report clk rate errors")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Patrik John <patrik.john@u-blox.com>
Link: https://lore.kernel.org/r/sig.19614244f8.20211123132737.88341-1-patrik.john@u-blox.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:26:32 +01:00
Johan Hovold
0b993fc1fe serial: liteuart: relax compile-test dependencies
The LITEX symbol is neither a build or runtime dependency for the
liteuart serial driver.

LITEX is selected by the "LiteX SoC Controller" driver, which does a
probe-time register-access sanity check and panics if the SoC has not
been configured correctly. That driver's Kconfig entry asserts that any
LiteX driver using the LiteX register accessors should depend on LITEX,
but currently only the serial driver complies.

Relax this LITEX "dependency" in order to make it easier to compile test
the driver.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211117100512.5058-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:25:49 +01:00
Johan Hovold
dd5e90b16c serial: liteuart: fix minor-number leak on probe errors
Make sure to release the allocated minor number before returning on
probe errors.

Fixes: 1da81e5562 ("drivers/tty/serial: add LiteUART driver")
Cc: stable@vger.kernel.org      # 5.11
Cc: Filip Kokosinski <fkokosinski@antmicro.com>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Reviewed-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211117100512.5058-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:25:49 +01:00
Johan Hovold
05f929b395 serial: liteuart: fix use-after-free and memleak on unbind
Deregister the port when unbinding the driver to prevent it from being
used after releasing the driver data and leaking memory allocated by
serial core.

Fixes: 1da81e5562 ("drivers/tty/serial: add LiteUART driver")
Cc: stable@vger.kernel.org      # 5.11
Cc: Filip Kokosinski <fkokosinski@antmicro.com>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Reviewed-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211117100512.5058-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:25:49 +01:00
Ilia Sergachev
0f55f89d98 serial: liteuart: Fix NULL pointer dereference in ->remove()
drvdata has to be set in _probe() - otherwise platform_get_drvdata()
causes null pointer dereference BUG in _remove().

Fixes: 1da81e5562 ("drivers/tty/serial: add LiteUART driver")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ilia Sergachev <silia@ethz.ch>
Link: https://lore.kernel.org/r/20211115224944.23f8c12b@dtkw
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:25:24 +01:00
Sven Eckelmann
7492ffc90f tty: serial: msm_serial: Deactivate RX DMA for polling support
The CONSOLE_POLLING mode is used for tools like k(g)db. In this kind of
setup, it is often sharing a serial device with the normal system console.
This is usually no problem because the polling helpers can consume input
values directly (when in kgdb context) and the normal Linux handlers can
only consume new input values after kgdb switched back.

This is not true anymore when RX DMA is enabled for UARTDM controllers.
Single input values can no longer be received correctly. Instead following
seems to happen:

* on 1. input, some old input is read (continuously)
* on 2. input, two old inputs are read (continuously)
* on 3. input, three old input values are read (continuously)
* on 4. input, 4 previous inputs are received

This repeats then for each group of 4 input values.

This behavior changes slightly depending on what state the controller was
when the first input was received. But this makes working with kgdb
basically impossible because control messages are always corrupted when
kgdboc tries to parse them.

RX DMA should therefore be off when CONSOLE_POLLING is enabled to avoid
these kind of problems. No such problem was noticed for TX DMA.

Fixes: 9969394501 ("tty: serial: msm: Add RX DMA support")
Cc: stable@vger.kernel.org
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Link: https://lore.kernel.org/r/20211113121050.7266-1-sven@narfation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:23:34 +01:00
Pierre Gondois
ac442a077a serial: pl011: Add ACPI SBSA UART match id
The document 'ACPI for Arm Components 1.0' defines the following
_HID mappings:
-'Prime cell UART (PL011)': ARMH0011
-'SBSA UART': ARMHB000

Use the sbsa-uart driver when a device is described with
the 'ARMHB000' _HID.

Note:
PL011 devices currently use the sbsa-uart driver instead of the
uart-pl011 driver. Indeed, PL011 devices are not bound to a clock
in ACPI. It is not possible to change their baudrate.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Link: https://lore.kernel.org/r/20211109172248.19061-1-Pierre.Gondois@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:23:28 +01:00
Johan Hovold
00de977f9e serial: core: fix transmit-buffer reset and memleak
Commit 761ed4a945 ("tty: serial_core: convert uart_close to use
tty_port_close") converted serial core to use tty_port_close() but
failed to notice that the transmit buffer still needs to be freed on
final close.

Not freeing the transmit buffer means that the buffer is no longer
cleared on next open so that any ioctl() waiting for the buffer to drain
might wait indefinitely (e.g. on termios changes) or that stale data can
end up being transmitted in case tx is restarted.

Furthermore, the buffer of any port that has been opened would leak on
driver unbind.

Note that the port lock is held when clearing the buffer pointer due to
the ldisc race worked around by commit a5ba1d95e4 ("uart: fix race
between uart_put_char() and uart_shutdown()").

Also note that the tty-port shutdown() callback is not called for
console ports so it is not strictly necessary to free the buffer page
after releasing the lock (cf. d72402145a ("tty/serial: do not free
trasnmit buffer page under port lock")).

Link: https://lore.kernel.org/r/319321886d97c456203d5c6a576a5480d07c3478.1635781688.git.baruch@tkos.co.il
Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Cc: stable@vger.kernel.org      # 4.9
Cc: Rob Herring <robh@kernel.org>
Reported-by: Baruch Siach <baruch@tkos.co.il>
Tested-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211108085431.12637-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 18:23:08 +01:00
Juergen Gross
0239143490 xen: flag hvc_xen to be not essential for system boot
The Xen pv console driver is not essential for boot. Set the respective
flag.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20211022064800.14978-4-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-23 13:42:08 -06:00
Linus Torvalds
abfecb3909 Merge tag 'tty-5.16-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 and serial driver updates for 5.16-rc1.

  Nothing major in here at all, just lots of tiny serial and tty driver
  updates for various reported things, and some good cleanups. These
  include:

   - more good tty api cleanups from Jiri

   - stm32 serial driver updates

   - softlockup fix for non-preempt systems under high serial load

   - rpmsg serial driver update

   - 8250 drivers updates and fixes

   - n_gsm line discipline fixes and updates as people are finally
     starting to use it.

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

* tag 'tty-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (86 commits)
  tty: Fix extra "not" in TTY_DRIVER_REAL_RAW description
  serial: cpm_uart: Protect udbg definitions by CONFIG_SERIAL_CPM_CONSOLE
  tty: rpmsg: Define tty name via constant string literal
  tty: rpmsg: Add pr_fmt() to prefix messages
  tty: rpmsg: Use dev_err_probe() in ->probe()
  tty: rpmsg: Unify variable used to keep an error code
  tty: rpmsg: Assign returned id to a local variable
  serial: stm32: push DMA RX data before suspending
  serial: stm32: terminate / restart DMA transfer at suspend / resume
  serial: stm32: rework RX dma initialization and release
  serial: 8250_pci: Remove empty stub pci_quatech_exit()
  serial: 8250_pci: Replace custom pci_match_id() implementation
  serial: xilinx_uartps: Fix race condition causing stuck TX
  serial: sunzilog: Mark sunzilog_putchar() __maybe_unused
  Revert "tty: hvc: pass DMA capable memory to put_chars()"
  Revert "virtio-console: remove unnecessary kmemdup()"
  serial: 8250_pci: Replace dev_*() by pci_*() macros
  serial: 8250_pci: Get rid of redundant 'else' keyword
  serial: 8250_pci: Refactor the loop in pci_ite887x_init()
  tty: add rpmsg driver
  ...
2021-11-04 09:09:37 -07:00
Geert Uytterhoeven
d142585bce serial: cpm_uart: Protect udbg definitions by CONFIG_SERIAL_CPM_CONSOLE
If CONFIG_CONSOLE_POLL=y, and CONFIG_SERIAL_CPM=m (hence
CONFIG_SERIAL_CPM_CONSOLE=n):

    drivers/tty/serial/cpm_uart/cpm_uart_core.c:1109:12: warning: ‘udbg_cpm_getc’ defined but not used [-Wunused-function]
     1109 | static int udbg_cpm_getc(void)
	  |            ^~~~~~~~~~~~~
    drivers/tty/serial/cpm_uart/cpm_uart_core.c:1095:13: warning: ‘udbg_cpm_putc’ defined but not used [-Wunused-function]
     1095 | static void udbg_cpm_putc(char c)
	  |             ^~~~~~~~~~~~~

Fix this by making the udbg definitions depend on
CONFIG_SERIAL_CPM_CONSOLE, in addition to CONFIG_CONSOLE_POLL.

Fixes: a60526097f ("tty: serial: cpm_uart: Add udbg support for enabling xmon")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211027075326.3270785-1-geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-30 11:01:48 +02:00
Andy Shevchenko
73a3d4f418 tty: rpmsg: Define tty name via constant string literal
Driver uses already twice the same string literal.

Define it in one place, so every user will have this
name consistent.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211025135148.53944-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:19:42 +02:00
Andy Shevchenko
88af70be4a tty: rpmsg: Add pr_fmt() to prefix messages
Make all messages to be prefixed in a unified way.
Add pr_fmt() to achieve this.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211025135148.53944-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:19:41 +02:00
Andy Shevchenko
8673ef7bd9 tty: rpmsg: Use dev_err_probe() in ->probe()
It's fine to use dev_err_probe() in ->probe() even if we know
it won't be deferred.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211025135148.53944-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:19:41 +02:00
Andy Shevchenko
408a507996 tty: rpmsg: Unify variable used to keep an error code
In some ret is used, in the other err. Let's unify it across the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211025135148.53944-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:19:41 +02:00
Andy Shevchenko
0572da285d tty: rpmsg: Assign returned id to a local variable
Instead of putting garbage in the data structure, assign allocated id
or an error code to a temporary variable. This makes code cleaner.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211025135148.53944-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:19:41 +02:00
Erwan Le Ray
6333a48506 serial: stm32: push DMA RX data before suspending
Data may be stored in DMA RX buffer, when suspending. The data needs
to be pushed to the upper layer. We can't rely on the timeout IRQ (RTOR)
that can't be triggered into low power state. So safely clear DMA request
(DMAR), force the DMA reception routines to push RX buffer content, before
disabling RX DMA. This way, handover to pio mode is safe.
Only call tty_flip_buffer_push() when there is RX data to handle.

Move the locking outside of stm32_usart_receive_chars() to prevent a race
condition, when disabling DMA request upon suspend / pm_runtime_suspend.
Data may be received under IRQ and pushed before
stm32_usart_receive_chars() has pushed older data from DMA rx_buf upon
suspend.
The sequence in suspend routine needs proper locking to avoid this.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:18:47 +02:00
Erwan Le Ray
6eeb348c84 serial: stm32: terminate / restart DMA transfer at suspend / resume
DMA prevents the system to suspend when an UART RX wake-up source is
using DMA. DMA can't suspend while DMA channels are still active.

Terminate DMA transfer at suspend, and restart a new DMA transfer at
resume. Create stm32_usart_start_rx_dma_cyclic function to factorize
dma RX initialization. Move RX DMA code related to wakeup into
stm32_usart_serial_en_wakeup() routine to ease further improvements
on wakeup from low power modes.

Don't enable/disable wakeup on uninitialized port.

There may be data residue in the RX FIFO while suspending. Flush it at
suspend time. Receiver timeout interrupt won't trigger later in low power
mode, so call stm32_usart_receive_chars() in case there's data to handle.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:18:47 +02:00
Erwan Le Ray
e0abc903de serial: stm32: rework RX dma initialization and release
The RX DMA channel is kept active forever (from the probe). That prevents
going to low power mode when it is used. This change moves the
DMA configuration and enabling procedures to startup routine to allow
transition to low power mode.
The DMA disabling procedure is implemented in stop_rx routine as this
ops has to stop characters reception, and DMA transation in shutdown.
Clean useless dma_async_tx_descriptor initialization to NULL value.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:18:47 +02:00
Andy Shevchenko
175003d7f9 serial: 8250_pci: Remove empty stub pci_quatech_exit()
The ->exit() callback is checked for presence anyway,
no need to have an empty stub.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211026133452.61657-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:18:10 +02:00
Andy Shevchenko
4290242776 serial: 8250_pci: Replace custom pci_match_id() implementation
Replace pci_quatech_amcc() with generic pci_match_id().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211026133452.61657-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:18:10 +02:00
Anssi Hannula
88b20f84f0 serial: xilinx_uartps: Fix race condition causing stuck TX
xilinx_uartps .start_tx() clears TXEMPTY when enabling TXEMPTY to avoid
any previous TXEVENT event asserting the UART interrupt. This clear
operation is done immediately after filling the TX FIFO.

However, if the bytes inserted by cdns_uart_handle_tx() are consumed by
the UART before the TXEMPTY is cleared, the clear operation eats the new
TXEMPTY event as well, causing cdns_uart_isr() to never receive the
TXEMPTY event. If there are bytes still queued in circbuf, TX will get
stuck as they will never get transferred to FIFO (unless new bytes are
queued to circbuf in which case .start_tx() is called again).

While the racy missed TXEMPTY occurs fairly often with short data
sequences (e.g. write 1 byte), in those cases circbuf is usually empty
so no action on TXEMPTY would have been needed anyway. On the other
hand, longer data sequences make the race much more unlikely as UART
takes longer to consume the TX FIFO. Therefore it is rare for this race
to cause visible issues in general.

Fix the race by clearing the TXEMPTY bit in ISR *before* filling the
FIFO.

The TXEMPTY bit in ISR will only get asserted at the exact moment the
TX FIFO *becomes* empty, so clearing the bit before filling FIFO does
not cause an extra immediate assertion even if the FIFO is initially
empty.

This is hard to reproduce directly on a normal system, but inserting
e.g. udelay(200) after cdns_uart_handle_tx(port), setting 4000000 baud,
and then running "dd if=/dev/zero bs=128 of=/dev/ttyPS0 count=50"
reliably reproduces the issue on my ZynqMP test system unless this fix
is applied.

Fixes: 85baf542d5 ("tty: xuartps: support 64 byte FIFO size")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Link: https://lore.kernel.org/r/20211026102741.2910441-1-anssi.hannula@bitwise.fi
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:17:05 +02:00
Geert Uytterhoeven
159f1f9e46 serial: sunzilog: Mark sunzilog_putchar() __maybe_unused
If CONSOLE_POLL=n, CONFIG_SERIAL_SUNZILOG_CONSOLE=n, and CONFIG_SERIO=m:

    drivers/tty/serial/sunzilog.c:1128:13: error: ‘sunzilog_putchar’ defined but not used [-Werror=unused-function]
     1128 | static void sunzilog_putchar(struct uart_port *port, int ch)
	  |             ^~~~~~~~~~~~~~~~

Fix this by marking sunzilog_putchar() __maybe_unused.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211026080426.2444756-1-geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:15:04 +02:00
Greg Kroah-Hartman
60f41e8484 Revert "tty: hvc: pass DMA capable memory to put_chars()"
This reverts commit 0986d7bc55.

It still has some issues and needs to be dropped at this point in time.

Link: https://lore.kernel.org/r/208f7a41-a9fa-630c-cb44-c37c503f3a72@kernel.org
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Cc: Xianting Tian <xianting.tian@linux.alibaba.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 08:48:09 +02:00
Andy Shevchenko
1177384179 serial: 8250_pci: Replace dev_*() by pci_*() macros
PCI subsystem provides convenient shortcut macros for message printing.
Use those macros instead of dev_*().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jiri Slaby <jslaby@kernel.org>
Link: https://lore.kernel.org/r/20211022135147.70965-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 08:41:20 +02:00
Andy Shevchenko
0187f884e2 serial: 8250_pci: Get rid of redundant 'else' keyword
The 'else' keyword is not needed when previous conditional branch returns
to the upper layer. Get rid of redundant 'else' keyword in such cases.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jiri Slaby <jslaby@kernel.org>
Link: https://lore.kernel.org/r/20211022135147.70965-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 08:41:13 +02:00
Andy Shevchenko
35b4f17231 serial: 8250_pci: Refactor the loop in pci_ite887x_init()
The loop can be refactored by using ARRAY_SIZE() instead of NULL terminator.
This reduces code base and makes it easier to read and understand.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jiri Slaby <jslaby@kernel.org>
Link: https://lore.kernel.org/r/20211022135147.70965-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 08:41:00 +02:00
Arnaud Pouliquen
7c0408d805 tty: add rpmsg driver
This driver exposes a standard TTY interface on top of the rpmsg
framework through a rpmsg service.

This driver supports multi-instances, offering a /dev/ttyRPMSGx entry
per rpmsg endpoint.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20211015094701.5732-3-arnaud.pouliquen@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 12:35:35 +02:00
Johan Hovold
74365bc138 serial: 8250_dw: drop bogus uartclk optimisation
The driver was updating the port uartclk before setting the new rate in
an attempt to avoid having the clock notifier redundantly update the
divisors.

The set_termios() callback is however called under the termios semaphore
and tty-port mutex so the worker scheduled by the clock notifier will
block in serial8250_update_uartclk() until the uartclk and divisors have
been updated anyway.

Drop the unnecessary swaps and incorrect comment and simply update the
uartclk field if the clock-rate change was successful.

Tested-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211015111422.1027-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 10:38:49 +02:00
Johan Hovold
d2248ca8d6 serial: 8250: rename unlock labels
Rename a couple of oddly named labels that are used to unlock before
returning after what they do (rather than after the context they are
used in) to improve readability.

Tested-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211015111422.1027-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 10:37:10 +02:00
Johan Hovold
211cde4f58 serial: 8250: fix racy uartclk update
Commit 868f3ee6e4 ("serial: 8250: Add 8250 port clock update method")
added a hack to support SoCs where the UART reference clock can
change behind the back of the driver but failed to add the proper
locking.

First, make sure to take a reference to the tty struct to avoid
dereferencing a NULL pointer if the clock change races with a hangup.

Second, the termios semaphore must be held during the update to prevent
a racing termios change.

Fixes: 868f3ee6e4 ("serial: 8250: Add 8250 port clock update method")
Fixes: c8dff3aa82 ("serial: 8250: Skip uninitialized TTY port baud rate update")
Cc: stable@vger.kernel.org      # 5.9
Cc: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211015111422.1027-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 10:37:10 +02:00
Erwan Le Ray
d1ec8a2eab serial: stm32: update throttle and unthrottle ops for dma mode
Disable DMA request line (if enabled) to switch in PIO mode in throttle
ops, so the RX data gets queues into the FIFO. The hardware flow control
is triggered when the RX FIFO is full.

Switch back to DMA mode (re-enable DMA request line) in unthrottle ops.
Hardware flow control is stopped when FIFO is not full anymore.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211020150332.10214-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 10:36:29 +02:00
Erwan Le Ray
33bb2f6ac3 serial: stm32: rework RX over DMA
This patch reworks RX support over DMA to improve reliability:
- change dma buffer cyclic configuration by using 2 periods. DMA buffer
data are handled by a flip-flop between the 2 periods in order to avoid
risk of data loss/corruption
- change the size of dma buffer to 4096 to limit overruns
- add rx errors management (breaks, parity, framing and overrun).
  When an error occurs on the uart line, the dma request line is masked at
  HW level. The SW must 1st clear DMAR (dma request line enable), to
  handle the error, then re-enable DMAR to recover. So, any correct data
  is taken from the DMA buffer, before handling the error itself. Then
  errors are handled from RDR/ISR/FIFO (e.g. in PIO mode). Last, DMA
  reception is resumed.
- add a condition on DMA request line in DMA RX routines in order to
switch to PIO mode when no DMA request line is disabled, even if the DMA
channel is still enabled.
  When the UART is wakeup source and is configured to use DMA for RX, any
  incoming data that wakes up the system isn't correctly received.
  At data reception, the irq_handler handles the WUF irq, and then the
  data reception over DMA.
  As the DMA transfer has been terminated at suspend, and will be restored
  by resume callback (which has no yet been called by system), the data
  can't be received.
  The wake-up data has to be handled in PIO mode while suspend callback
  has not been called.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211020150332.10214-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 10:36:29 +02:00
Erwan Le Ray
cc58d0a3f0 serial: stm32: re-introduce an irq flag condition in usart_receive_chars
Re-introduce an irq flag condition in usart_receive_chars.
This condition has been deleted by commit 75f4e830fa ("serial: do not
restore interrupt state in sysrq helper").
This code was present to handle threaded case, and has been removed
because it is no more needed in this case. Nevertheless an irq safe lock
is still needed in some cases, when DMA should be stopped to receive errors
or breaks in PIO mode.
This patch is a precursor to the complete rework or stm32 serial driver
DMA implementation.

Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211020150332.10214-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 10:36:29 +02:00
Xianting Tian
0986d7bc55 tty: hvc: pass DMA capable memory to put_chars()
As well known, hvc backend can register its opertions to hvc backend.
the operations contain put_chars(), get_chars() and so on.

Some hvc backend may do dma in its operations. eg, put_chars() of
virtio-console. But in the code of hvc framework, it may pass DMA
incapable memory to put_chars() under a specific configuration, which
is explained in commit c4baad5029(virtio-console: avoid DMA from stack):
1, c[] is on stack,
   hvc_console_print():
        char c[N_OUTBUF] __ALIGNED__;
        cons_ops[index]->put_chars(vtermnos[index], c, i);
2, ch is on stack,
   static void hvc_poll_put_char(,,char ch)
   {
        struct tty_struct *tty = driver->ttys[0];
        struct hvc_struct *hp = tty->driver_data;
        int n;

        do {
                n = hp->ops->put_chars(hp->vtermno, &ch, 1);
        } while (n <= 0);
   }

Commit c4baad5029 is just the fix to avoid DMA from stack memory, which
is passed to virtio-console by hvc framework in above code. But I think
the fix is aggressive, it directly uses kmemdup() to alloc new buffer
from kmalloc area and do memcpy no matter the memory is in kmalloc area
or not. But most importantly, it should better be fixed in the hvc
framework, by changing it to never pass stack memory to the put_chars()
function in the first place. Otherwise, we still face the same issue if
a new hvc backend using dma added in the furture.

In this patch, add 'char cons_outbuf[]' as part of 'struct hvc_struct',
so hp->cons_outbuf is no longer the stack memory, we can use it in above
cases safely. We also add lock to protect cons_outbuf instead of using
the global lock of hvc.

Introduce another array(cons_hvcs[]) for hvc pointers next to the
cons_ops[] and vtermnos[] arrays. With the array, we can easily find
hvc's cons_outbuf and its lock.

With the patch, we can revert the fix c4baad5029.

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Link: https://lore.kernel.org/r/20211015024658.1353987-3-xianting.tian@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21 10:34:33 +02:00