Hi,
On 4/22/24 17:06, 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/STM32MP13 platforms, above ram_top, there is one
reserved-memory region tagged "no-map" dedicated to OP-TEE :
_ addr=de000000 size=2000000 for stm32mp157x-dkx and stm32mp135f-dk
_ addr=fe000000 size=2000000 for stm32mp157c-ev1
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
in case of stm32mp157x-dkx / stm32mp135f-dk or addr=fe000000 size=2000000
in case for stm2mp157c-ev1)
but now with LMB_NOMAP tag which produces the following error message :
_ for stm32mp157x-dkx / stm32mp135f-dk :
"ERROR: reserving fdt memory region failed (addr=de000000 size=2000000
flags=4)"
_ for stm32mp157c-ev1 :
"ERROR: reserving fdt memory region failed (addr=fe000000 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 <[email protected]>
---
Changes in v2:
_ update commit message by adding information about memory area
dedicated for OPTEE for various STM32MP1/STM32MP13 boards.
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);
+}
It seen like a temporary workaround after commit 7b78d6438a2b3
("efi_loader: Reserve unaccessible memory") to avoid warnings.
And it is working because in the default memory mapping
OP-TEE base address == RAM_TOP and the rest of memory is
used by OP-TEE tagged "no map" (protected by firewall)
Reviewed-by: Patrick Delaunay <[email protected]>
FYI: workaround because the memory above ram_top is
"already occupied by firmware" =
and it is OP-TEE for STM32MP2 platform.
For me the LMB type used by EFI in not correct for OP-TEE usage region
with "no-map" tag in device tree= see boot_fdt_add_mem_rsv_regions()
for linux DT parsing
and we have no way to indicated this LMB tag= LMB_NOMAP with EFI stack
(with enum efi_memory_type ?)
EFI_BOOT_SERVICES_DATA => doesn't means NOMAP flag for LMB....
so something is missing in EFI side like EFI_BOOT_NOMAP to be used in board
implementation of efi_add_known_memory() ?
Thanks
Patrick
