[PATCH v2 6/6] lib: utils/fdt: Disable GPIO restart and poweroff nodes in fdt_fixups()

[Bin Meng]

On Fri, Jul 9, 2021 at 9:13 PM Anup Patel <anup.patel at wdc.com> wrote:
>
> We now have SBI SRST extension provided via generic GPIO restart and
> poweroff similar to Linux kernel so let's disable corresponding
> device tree nodes in fdt_fixups().
>
> Signed-off-by: Anup Patel <anup.patel at wdc.com>
> ---
>  include/sbi_utils/fdt/fdt_fixup.h | 17 +++++++++++++++--
>  lib/utils/fdt/fdt_fixup.c         | 25 +++++++++++++++++++++++--
>  2 files changed, 38 insertions(+), 4 deletions(-)
>
> diff --git a/include/sbi_utils/fdt/fdt_fixup.h b/include/sbi_utils/fdt/fdt_fixup.h
> index c38e5d9..cc86440 100644
> --- a/include/sbi_utils/fdt/fdt_fixup.h
> +++ b/include/sbi_utils/fdt/fdt_fixup.h
> @@ -21,6 +21,18 @@
>   */
>  void fdt_cpu_fixup(void *fdt);
>
> +/**
> + * Fix up the GPIO restart and poweroff nodes in the device tree
> + *
> + * This routine disabls the GPIO restart and poweroff nodes in the device

typo: disables

> + * tree because OpenSBI provides SBI SRST extension based on it.
> + *
> + * It is recommended that platform codes call this helper in their final_init()
> + *
> + * @param fdt: device tree blob
> + */
> +void fdt_gpio_reset_fixup(void *fdt);
> +
>  /**
>   * Fix up the PLIC node in the device tree
>   *
> @@ -64,8 +76,9 @@ int fdt_reserved_memory_nomap_fixup(void *fdt);
>   * General device tree fix-up
>   *
>   * This routine do all required device tree fix-ups for a typical platform.
> - * It fixes up the PLIC node and the reserved memory node in the device tree
> - * by calling the corresponding helper routines to accomplish the task.
> + * It fixes up the GPIO restart/poweroff node, PLIC node and the reserved
> + * memory node in the device tree by calling the corresponding helper
> + * routines to accomplish the task.
>   *
>   * It is recommended that platform codes call this helper in their final_init()
>   *
> diff --git a/lib/utils/fdt/fdt_fixup.c b/lib/utils/fdt/fdt_fixup.c
> index 1465500..52d1a0e 100644
> --- a/lib/utils/fdt/fdt_fixup.c
> +++ b/lib/utils/fdt/fdt_fixup.c
> @@ -51,6 +51,27 @@ void fdt_cpu_fixup(void *fdt)
>         }
>  }
>
> +void fdt_gpio_reset_fixup(void *fdt)
> +{
> +       int err, nodeoff;
> +
> +       nodeoff = fdt_node_offset_by_compatible(fdt, 0, "gpio-poweroff");
> +       if (nodeoff >= 0) {
> +               err = fdt_open_into(fdt, fdt, fdt_totalsize(fdt) + 32);
> +               if (err < 0)
> +                       return;
> +               fdt_setprop_string(fdt, nodeoff, "status", "disabled");

For OS that already supports gpio-poweroff/restart natively in the
kernel, but has not yet to support SBI SRST extension, this change
suddenly breaks them.

> +       }
> +
> +       nodeoff = fdt_node_offset_by_compatible(fdt, 0, "gpio-restart");
> +       if (nodeoff >= 0) {
> +               err = fdt_open_into(fdt, fdt, fdt_totalsize(fdt) + 32);
> +               if (err < 0)
> +                       return;
> +               fdt_setprop_string(fdt, nodeoff, "status", "disabled");
> +       }
> +}
> +
>  void fdt_plic_fixup(void *fdt)
>  {
>         u32 *cells;
> @@ -260,9 +281,9 @@ int fdt_reserved_memory_nomap_fixup(void *fdt)
>
>  void fdt_fixups(void *fdt)
>  {
> +       fdt_gpio_reset_fixup(fdt);
> +
>         fdt_plic_fixup(fdt);
>
>         fdt_reserved_memory_fixup(fdt);
>  }

Regards,
Bin