[Uboot-stm32] [PATCH] stm32mp: Reserve OPTEE area in EFI memory map

[Patrice CHOTARD]

On 4/19/24 09:44, Patrice CHOTARD wrote:
> 
> 
> On 4/17/24 09:45, Heinrich Schuchardt wrote:
>> On 17.04.24 09:25, Patrick DELAUNAY wrote:
>>> 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);
>>
>> With this change the EFI memory map passed to the operating system will
>> not contain any memory above gd->ram_top. Is this really your intent?
>> Don't you have any memory above 0xe0000000?
> 
> Hi Heinrich
> 
> On stm32mp157x-dk and stm32mp135x-dk boards, there is no memory above 0xe0000000.
> But, on stm32mp157x-ed1 or stm32mp157x-ev1, you are right, we got memory above 0xe0000000.
> 
> I will rework this patch to take into account memory that could be present above OPTEE area.

After double checking, this patch is correct but i need to update the commit message.

In fact for stm32mp157x-dk and stm32mp135x-dk boards, there is 512MB of memory (0xc0000000 0x20000000),
OPTEE is located at the end of memory : 0xde000000 0x02000000

But for stm32mp157c-ev1, there is 1GB of memory (0xC0000000 0x40000000), and identically,
OPTEE is located at the end of memory : 0xfe000000 0x2000000

So in both cases, above OPTEE reserved-memory area, there is no more free memory.

Thanks
Patrice

> 
> Thanks for pointing this
> Patrice
> 
>>
>> Best regards
>>
>> Heinrich
>>
>>>> +}
>>>
>>>
>>>
>>> Reviewed-by: Patrick Delaunay <patrick.delaunay at foss.st.com>
>>>
>>> Thanks
>>> Patrick
>>>
>>
> _______________________________________________
> Uboot-stm32 mailing list
> Uboot-stm32 at st-md-mailman.stormreply.com
> https://st-md-mailman.stormreply.com/mailman/listinfo/uboot-stm32