[PATCH] stm32mp: Reserve OPTEE area in EFI memory map

[Patrick DELAUNAY]

Hi,

On 3/8/24 11:12, Patrice Chotard wrote:
> Since commit 7b78d6438a2b3 ("efi_loader: Reserve unaccessible memory")
> memory region above ram_top is tagged in EFI memory map as
> EFI_BOOT_SERVICES_DATA.
> In case of STM32MP1 platform, above ram_top, there is one reserved-memory
> region tagged "no-map" dedicated to OP-TEE (addr=de000000 size=2000000).
>
> Before booting kernel, EFI memory map is first built, the OPTEE region is
> tagged as EFI_BOOT_SERVICES_DATA and when reserving LMB, the tag LMB_NONE
> is used.
>
> Then after, the LMB are completed by boot_fdt_add_mem_rsv_regions()
> which try to add again the same OPTEE region (addr=de000000 size=2000000)
> but now with LMB_NOMAP tag which produces the following error message :
>
> "ERROR: reserving fdt memory region failed (addr=de000000 size=2000000 flags=4)"
>
> To avoid this, OPTEE area shouldn't be used by EFI, so we need to mark
> it as reserved.
>
> Signed-off-by: Patrice Chotard <patrice.chotard at foss.st.com>
> ---
>
>   arch/arm/mach-stm32mp/dram_init.c | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
>
> diff --git a/arch/arm/mach-stm32mp/dram_init.c b/arch/arm/mach-stm32mp/dram_init.c
> index fb1208fc5d5..f67f54f2ae0 100644
> --- a/arch/arm/mach-stm32mp/dram_init.c
> +++ b/arch/arm/mach-stm32mp/dram_init.c
> @@ -7,6 +7,7 @@
>   
>   #include <common.h>
>   #include <dm.h>
> +#include <efi_loader.h>
>   #include <image.h>
>   #include <init.h>
>   #include <lmb.h>
> @@ -75,3 +76,14 @@ phys_addr_t board_get_usable_ram_top(phys_size_t total_size)
>   
>   	return reg + size;
>   }
> +
> +void efi_add_known_memory(void)
> +{
> +	if (IS_ENABLED(CONFIG_EFI_LOADER))
> +		/*
> +		 * Memory over ram_top is reserved to OPTEE.
> +		 * Declare to EFI only memory area below ram_top
> +		 */
> +		efi_add_memory_map(gd->ram_base, gd->ram_top - gd->ram_base,
> +				   EFI_CONVENTIONAL_MEMORY);
> +}



Reviewed-by: Patrick Delaunay <patrick.delaunay at foss.st.com>

Thanks
Patrick