kernel/drivers/tty/hvc/Kconfig, branch linux-6.9.y

tty: hvc: Don't enable the RISC-V SBI console by default

2024-02-19T08:43:33Z

The new SBI console has the same problem as the old one: there's only one shared backing hardware and no synchronization, so the two drivers end up stepping on each other. This was the same issue the old SBI-0.1 console drivers had, but that was disabled by default when SBI-0.1 was. So just mark the new driver as nonportable. Reported-by: Emil Renner Berthing Fixes: 88ead68e764c ("tty: Add SBI debug console support to HVC SBI driver") Signed-off-by: Palmer Dabbelt Reviewed-by: Paul Walmsley Reviewed-by: Anup Patel Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20240214153429.16484-2-palmer@rivosinc.com Signed-off-by: Greg Kroah-Hartman

tty: Add SBI debug console support to HVC SBI driver

2024-01-10T15:04:05Z

RISC-V SBI specification supports advanced debug console support via SBI DBCN extension. Extend the HVC SBI driver to support it. Signed-off-by: Atish Patra Signed-off-by: Anup Patel Reviewed-by: Andrew Jones Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20231124070905.1043092-5-apatel@ventanamicro.com Signed-off-by: Palmer Dabbelt

tty: hvc: dcc: Bind driver to CPU core0 for reads and writes

2022-05-05T20:45:57Z

Some external debuggers do not handle reads/writes from/to DCC on secondary cores. Each core has its own DCC device registers, so when a core reads or writes from/to DCC, it only accesses its own DCC device. Since kernel code can run on any core, every time the kernel wants to write to the console, it might write to a different DCC. In SMP mode, external debugger creates multiple windows, and each window shows the DCC output only from that core's DCC. The result is that console output is either lost or scattered across windows. Selecting this debug option will enable code that serializes all console input and output to core 0. The DCC driver will create input and output FIFOs that all cores will use. Reads and writes from/to DCC are handled by a workqueue that runs only core 0. This is a debug feature to be used only in early stage development where debug serial console support would not be present. It disables PM feature like CPU hotplug and is not suitable for production environment. Signed-off-by: Shanker Donthineni Acked-by: Adam Wallis Signed-off-by: Timur Tabi Signed-off-by: Elliot Berman Signed-off-by: Sai Prakash Ranjan Link: https://lore.kernel.org/r/20220428090858.14489-1-quic_saipraka@quicinc.com Signed-off-by: Greg Kroah-Hartman

tty: hvc: fix link error with CONFIG_SERIAL_CORE_CONSOLE=n

2020-09-27T12:17:43Z

aarch64-linux-gnu-ld: drivers/tty/hvc/hvc_dcc.o: in function `dcc_early_write': hvc_dcc.c:(.text+0x164): undefined reference to `uart_console_write' The driver uses the uart_console_write(), but SERIAL_CORE_CONSOLE is not selected, so uart_console_write is not defined, then we get the error. Fix this by selecting SERIAL_CORE_CONSOLE. Fixes: d1a1af2cdf19 ("hvc: dcc: Add earlycon support") Reported-by: Hulk Robot Signed-off-by: Yang Yingliang Link: https://lore.kernel.org/r/20200919063535.2809707-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman

tty: riscv: Using RISCV_SBI_V01 instead of RISCV_SBI

2020-04-21T23:15:04Z

As shown in SBI v0.2, the legacy console SBI functions (sbi_console_getchar() and sbi_console_putchar()) are expected to be deprecated; they have no replacement. Let's HVC_RISCV_SBI and SERIAL_EARLYCON_RISCV_SBI depends on RISCV_SBI_V01. Fixes: efca13989250 ("RISC-V: Introduce a new config for SBI v0.1") Signed-off-by: Kefeng Wang Reviewed-by: Anup Patel Signed-off-by: Palmer Dabbelt

tty: source all tty Kconfig files in one place

2020-03-12T16:17:30Z

'source' (include) all of the tty/*/Kconfig files from drivers/tty/Kconfig instead of from drivers/char/Kconfig. This consolidates them both in source code and in menu presentation to the user. Move hvc/Kconfig and serial/Kconfig 'source' lines into the if TTY/endif block and remove the if TTY/endif blocks from those 2 files. Cc: linux-serial@vger.kernel.org Cc: Jiri Slaby Cc: Greg Kroah-Hartman Cc: Arnd Bergmann Suggested-by: Jiri Slaby Suggested-by: Arnd Bergmann Acked-by: Arnd Bergmann Signed-off-by: Randy Dunlap Link: https://lore.kernel.org/r/20200311225736.32147-3-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman

Merge tag 'tty-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2019-12-03T22:09:14Z

Pull tty/serial updates from Greg KH: "Here is the "big" tty and serial driver patches for 5.5-rc1. It's a bit later in the merge window than normal as I wanted to make sure some last-minute patches applied to it were all sane. They seem to be :) There's a lot of little stuff in here, for the tty core, and for lots of serial drivers: - reverts of uartlite serial driver patches that were wrong - msm-serial driver fixes - serial core updates and fixes - tty core fixes - serial driver dma mapping api changes - lots of other tiny fixes and updates for serial drivers All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits) Revert "serial/8250: Add support for NI-Serial PXI/PXIe+485 devices" vcs: prevent write access to vcsu devices tty: vt: keyboard: reject invalid keycodes tty: don't crash in tty_init_dev when missing tty_port serial: stm32: fix clearing interrupt error flags tty: Fix Kconfig indentation, continued serial: serial_core: Perform NULL checks for break_ctl ops tty: remove unused argument from tty_open_by_driver() tty: Fix Kconfig indentation {tty: serial, nand: onenand}: samsung: rename to fix build warning serial: ifx6x60: add missed pm_runtime_disable serial: pl011: Fix DMA ->flush_buffer() Revert "serial-uartlite: Move the uart register" Revert "serial-uartlite: Add get serial id if not provided" Revert "serial-uartlite: Do not use static struct uart_driver out of probe()" Revert "serial-uartlite: Add runtime support" Revert "serial-uartlite: Change logic how console_port is setup" Revert "serial-uartlite: Use allocated structure instead of static ones" tty: serial: msm_serial: Use dma_request_chan() directly for channel request tty: serial: tegra: Use dma_request_chan() directly for channel request ...

tty: Fix Kconfig indentation, continued

2019-11-21T13:38:31Z

Adjust indentation from seven spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20191121132847.29015-1-krzk@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: Fix Kconfig indentation

2019-11-20T14:20:13Z

Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20191120133843.13189-1-krzk@kernel.org Signed-off-by: Greg Kroah-Hartman

riscv: don't allow selecting SBI based drivers for M-mode

2019-11-13T21:20:02Z

When running in M-mode we can't use SBI based drivers. Add a new CONFIG_RISCV_SBI that drivers that do SBI calls can depend on instead. Signed-off-by: Damien Le Moal Reviewed-by: Anup Patel Signed-off-by: Christoph Hellwig Signed-off-by: Paul Walmsley