[PATCH] riscv, qemu_fw_cfg: Add support for RISC-V architecture

[Alistair Francis]

On Wed, Oct 11, 2023 at 11:34 PM Björn Töpel <bjorn at kernel.org> wrote:
>
> From: Björn Töpel <bjorn at rivosinc.com>
>
> Qemu fw_cfg support was missing for RISC-V, which made it hard to do
> proper vmcore dumps from qemu.
>
> Add the missing RISC-V arch-defines.
>
> You can now do vmcore dumps from qemu. Add "-device vmcoreinfo" to the
> qemu command-line. From the qemu montior:
>   (qemu) dump-guest-memory vmcore
>
> The vmcore can now be used, e.g., with the "crash" utility.
>
> Signed-off-by: Björn Töpel <bjorn at rivosinc.com>

Acked-by: Alistair Francis <alistair.francis at wdc.com>

Alistair

> ---
>  drivers/firmware/Kconfig       | 2 +-
>  drivers/firmware/qemu_fw_cfg.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
> index b59e3041fd62..f05ff56629b3 100644
> --- a/drivers/firmware/Kconfig
> +++ b/drivers/firmware/Kconfig
> @@ -155,7 +155,7 @@ config RASPBERRYPI_FIRMWARE
>
>  config FW_CFG_SYSFS
>         tristate "QEMU fw_cfg device support in sysfs"
> -       depends on SYSFS && (ARM || ARM64 || PARISC || PPC_PMAC || SPARC || X86)
> +       depends on SYSFS && (ARM || ARM64 || PARISC || PPC_PMAC || RISCV || SPARC || X86)
>         depends on HAS_IOPORT_MAP
>         default n
>         help
> diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
> index a69399a6b7c0..1448f61173b3 100644
> --- a/drivers/firmware/qemu_fw_cfg.c
> +++ b/drivers/firmware/qemu_fw_cfg.c
> @@ -211,7 +211,7 @@ static void fw_cfg_io_cleanup(void)
>
>  /* arch-specific ctrl & data register offsets are not available in ACPI, DT */
>  #if !(defined(FW_CFG_CTRL_OFF) && defined(FW_CFG_DATA_OFF))
> -# if (defined(CONFIG_ARM) || defined(CONFIG_ARM64))
> +# if (defined(CONFIG_ARM) || defined(CONFIG_ARM64) || defined(CONFIG_RISCV))
>  #  define FW_CFG_CTRL_OFF 0x08
>  #  define FW_CFG_DATA_OFF 0x00
>  #  define FW_CFG_DMA_OFF 0x10
>
> base-commit: 1c8b86a3799f7e5be903c3f49fcdaee29fd385b5
> --
> 2.39.2
>
>