[PATCH v2 2/3] rpi5: initial support

[Peter Robinson]

> rpi5: add alternative way to get MBOX address via FDT
>  node

Same note about descriptive commit titles, it's useful not to have 3
consecutive commits with the same title.

> MBOX on RPI5/bcm2712 has a different offset. Find it via
> "brcm,bcm2835-mbox" node.

Do we do use the DT node just for the RPi5 and the old method for all
older RPi, or do we move all generations to finding it by DT?

> Signed-off-by: Dmitry Malkin <dmitry at bedrocksystems.com>
> ---
> v2:
>       new patch
> ---
>  arch/arm/mach-bcm283x/include/mach/base.h |  1 +
>  arch/arm/mach-bcm283x/include/mach/mbox.h |  4 ++--
>  arch/arm/mach-bcm283x/init.c              | 12 +++++++++++-
>  3 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-bcm283x/include/mach/base.h
> b/arch/arm/mach-bcm283x/include/mach/base.h
> index 4ccaf69693..8cd224921e 100644
> --- a/arch/arm/mach-bcm283x/include/mach/base.h
> +++ b/arch/arm/mach-bcm283x/include/mach/base.h
> @@ -7,6 +7,7 @@
>  #define _BCM283x_BASE_H_
>
>  extern unsigned long rpi_bcm283x_base;
> +extern unsigned long rpi_bcm283x_mbox_addr;
>
>  #ifdef CONFIG_ARMV7_LPAE
>  #ifdef CONFIG_TARGET_RPI_4_32B
> diff --git a/arch/arm/mach-bcm283x/include/mach/mbox.h
> b/arch/arm/mach-bcm283x/include/mach/mbox.h
> index 490664f878..ad086be467 100644
> --- a/arch/arm/mach-bcm283x/include/mach/mbox.h
> +++ b/arch/arm/mach-bcm283x/include/mach/mbox.h
> @@ -38,8 +38,8 @@
>
>  /* Raw mailbox HW */
>
> -#define BCM2835_MBOX_PHYSADDR ({ BUG_ON(!rpi_bcm283x_base); \
> -                 rpi_bcm283x_base + 0x0000b880; })
> +#define BCM2835_MBOX_PHYSADDR ({ BUG_ON(!rpi_bcm283x_mbox_addr); \
> +                 rpi_bcm283x_mbox_addr; })
>
>  struct bcm2835_mbox_regs {
>      u32 read;
> diff --git a/arch/arm/mach-bcm283x/init.c b/arch/arm/mach-bcm283x/init.c
> index 362838e9b9..aef3a31f29 100644
> --- a/arch/arm/mach-bcm283x/init.c
> +++ b/arch/arm/mach-bcm283x/init.c
> @@ -145,6 +145,11 @@ static void rpi_update_mem_map(void) {}
>
>  unsigned long rpi_bcm283x_base = 0x3f000000;
>
> +/* This is intialized before relocation. Enforce .data section usage.
> + * Otherwise it's going to .bss and will be zero after relocation.
> + */
> +unsigned long __section(".data") rpi_bcm283x_mbox_addr;
> +
>  int arch_cpu_init(void)
>  {
>      icache_enable();
> @@ -154,7 +159,7 @@ int arch_cpu_init(void)
>
>  int mach_cpu_init(void)
>  {
> -    int ret, soc_offset;
> +    int ret, soc_offset, mbox_offset;
>      u64 io_base, size;
>
>      rpi_update_mem_map();
> @@ -170,6 +175,11 @@ int mach_cpu_init(void)
>          return ret;
>
>      rpi_bcm283x_base = io_base;
> +    rpi_bcm283x_mbox_addr = rpi_bcm283x_base + 0xb880;
> +
> +    mbox_offset = fdt_node_offset_by_compatible((void*)gd->fdt_blob,
> soc_offset, "brcm,bcm2835-mbox");
> +    if (mbox_offset > soc_offset)
> +        rpi_bcm283x_mbox_addr =
> fdt_get_base_address((void*)gd->fdt_blob, mbox_offset);
>
>      return 0;
>  }
> --
> 2.40.1