efi_loader: Enable RISC-V support
We have almost all pieces needed to support RISC-V UEFI binaries in place already.
The only missing piece are ELF relocations for runtime code and
data.
This patch adds respective support in the linker script and the runtime
relocation code. It also allows users to enable the EFI_LOADER configuration
switch on RISC-V platforms.
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
index d38780b..2909e76 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -1,6 +1,6 @@
config EFI_LOADER
bool "Support running EFI Applications in U-Boot"
- depends on (ARM || X86) && OF_LIBFDT
+ depends on (ARM || X86 || RISCV) && OF_LIBFDT
# We do not support bootefi booting ARMv7 in non-secure mode
depends on !ARMV7_NONSEC
# We need EFI_STUB_64BIT to be set on x86_64 with EFI_STUB
diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
index 042f9ae..241090f 100644
--- a/lib/efi_loader/efi_runtime.c
+++ b/lib/efi_loader/efi_runtime.c
@@ -40,6 +40,25 @@
#include <asm/elf.h>
#define R_RELATIVE R_386_RELATIVE
#define R_MASK 0xffULL
+#elif defined(CONFIG_RISCV)
+#include <elf.h>
+#define R_RELATIVE R_RISCV_RELATIVE
+#define R_MASK 0xffULL
+#define IS_RELA 1
+
+struct dyn_sym {
+ ulong foo1;
+ ulong addr;
+ u32 foo2;
+ u32 foo3;
+};
+#ifdef CONFIG_CPU_RISCV_32
+#define R_ABSOLUTE R_RISCV_32
+#define SYM_INDEX 8
+#else
+#define R_ABSOLUTE R_RISCV_64
+#define SYM_INDEX 32
+#endif
#else
#error Need to add relocation awareness
#endif
@@ -246,15 +265,27 @@
p = (void*)((ulong)rel->offset - base) + gd->relocaddr;
- if ((rel->info & R_MASK) != R_RELATIVE) {
- continue;
- }
+ debug("%s: rel->info=%#lx *p=%#lx rel->offset=%p\n", __func__, rel->info, *p, rel->offset);
+ switch (rel->info & R_MASK) {
+ case R_RELATIVE:
#ifdef IS_RELA
newaddr = rel->addend + offset - CONFIG_SYS_TEXT_BASE;
#else
newaddr = *p - lastoff + offset;
#endif
+ break;
+#ifdef R_ABSOLUTE
+ case R_ABSOLUTE: {
+ ulong symidx = rel->info >> SYM_INDEX;
+ extern struct dyn_sym __dyn_sym_start[];
+ newaddr = __dyn_sym_start[symidx].addr + offset;
+ break;
+ }
+#endif
+ default:
+ continue;
+ }
/* Check if the relocation is inside bounds */
if (map && ((newaddr < map->virtual_start) ||