[PATCH v1] arm: mach-k3: common: EFI loader map memory below ram top

[Vitor Soares <ivitro@gmail.com>]

From: Vitor Soares <vitor.soares@toradex.com>

During the boot, the EFI loader maps the memory from ram_top to ram_end
as EFI_BOOT_SERVICES_DATA. When LMB does boot_fdt_add_mem_rsv_regions()
to OPTEE, TFA, R5, and M4F DMA/memory "no-map" for the kernel it produces
the following error message:

ERROR: reserving fdt memory region failed (addr=9cb00000 size=100000 flags=4)
ERROR: reserving fdt memory region failed (addr=9cc00000 size=e00000 flags=4)
ERROR: reserving fdt memory region failed (addr=9da00000 size=100000 flags=4)
ERROR: reserving fdt memory region failed (addr=9db00000 size=c00000 flags=4)
ERROR: reserving fdt memory region failed (addr=9e780000 size=80000 flags=4)
ERROR: reserving fdt memory region failed (addr=9e800000 size=1800000 flags=4)

To avoid this, don't flag with EFI_BOOT_SERVICES_DATA the memory from
ram_top to ram_end by the EFI loader.

Signed-off-by: Vitor Soares <vitor.soares@toradex.com>
---

Similar fix for the same issue can be found at
https://lore.kernel.org/all/20240308101230.2595220-1-patrice.chotard@foss.st.com/

 arch/arm/mach-k3/common.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm/mach-k3/common.c b/arch/arm/mach-k3/common.c
index b54f2ddc47..80e89b2a16 100644
--- a/arch/arm/mach-k3/common.c
+++ b/arch/arm/mach-k3/common.c
@@ -24,6 +24,7 @@
 #include <asm/io.h>
 #include <fs_loader.h>
 #include <fs.h>
+#include <efi_loader.h>
 #include <env.h>
 #include <elf.h>
 #include <soc.h>
@@ -607,3 +608,14 @@ void setup_qos(void)
 		writel(qos_data[i].val, (uintptr_t)qos_data[i].reg);
 }
 #endif
+
+void efi_add_known_memory(void)
+{
+	if (IS_ENABLED(CONFIG_EFI_LOADER))
+		/*
+		 * Memory over ram_top can be used by various firmware
+		 * 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);
+}
-- 
2.34.1