loongarch: Add ELF relocation types documentation and comments

See https://github.com/loongson/la-abi-specs/blob/release/laelf.adoc#relocations

Signed-off-by: Xiaotian Wu <wuxiaotian@loongson.cn>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Xiaotian Wu 2023-06-13 17:06:34 +08:00 committed by Daniel Kiper
parent 22a6f8a482
commit 857af0e17b

View File

@ -24,6 +24,10 @@
#include <grub/i18n.h>
#include <grub/loongarch64/reloc.h>
/*
* LoongArch relocations documentation:
* https://github.com/loongson/la-abi-specs/blob/release/laelf.adoc#relocations
*/
static void grub_loongarch64_stack_push (grub_loongarch64_stack_t stack, grub_uint64_t x);
static grub_uint64_t grub_loongarch64_stack_pop (grub_loongarch64_stack_t stack);
@ -200,6 +204,11 @@ grub_loongarch64_sop_32_s_0_10_10_16_s2 (grub_loongarch64_stack_t stack,
*place =(*place) | ((a >> 18) & 0x3ff);
}
/*
* B26 relocation for the 28-bit PC-relative jump
* (*(uint32_t *) PC) [9 ... 0] = (S + A - PC) [27 ... 18]
* (*(uint32_t *) PC) [25 ... 10] = (S + A - PC) [17 ... 2]
*/
void grub_loongarch64_b26 (grub_uint32_t *place, grub_int64_t offset)
{
grub_uint32_t val;
@ -215,6 +224,10 @@ void grub_loongarch64_b26 (grub_uint32_t *place, grub_int64_t offset)
*place |= grub_cpu_to_le32 (val) & ~insmask;
}
/*
* ABS_HI20/PCALA_HI20 relocations for 32/64-bit absolute address/PC-relative offset
* (*(uint32_t *) PC) [24 ... 5] = (S + A) [31 ... 12]
*/
void grub_loongarch64_xxx_hi20 (grub_uint32_t *place, grub_int64_t offset)
{
const grub_uint32_t insmask = grub_cpu_to_le32_compile_time (0xfe00001f);
@ -227,6 +240,10 @@ void grub_loongarch64_xxx_hi20 (grub_uint32_t *place, grub_int64_t offset)
*place |= grub_cpu_to_le32 (val) & ~insmask;
}
/*
* ABS_LO12/PCALA_LO12 relocations for 32/64-bit absolute address
* (*(uint32_t *) PC) [21 ... 10] = (S + A) [11 ... 0]
*/
void grub_loongarch64_xxx_lo12 (grub_uint32_t *place, grub_int64_t offset)
{
const grub_uint32_t insmask = grub_cpu_to_le32_compile_time (0xffc003ff);
@ -235,6 +252,10 @@ void grub_loongarch64_xxx_lo12 (grub_uint32_t *place, grub_int64_t offset)
*place |= grub_cpu_to_le32 (offset << 10) & ~insmask;
}
/*
* ABS64_HI12 relocation for the 64-bit absolute address
* (*(uint32_t *) PC) [21 ... 10] = (S + A) [63 ... 52]
*/
void grub_loongarch64_abs64_hi12 (grub_uint32_t *place, grub_int64_t offset)
{
const grub_uint32_t insmask = grub_cpu_to_le32_compile_time (0xffc003ff);
@ -247,6 +268,10 @@ void grub_loongarch64_abs64_hi12 (grub_uint32_t *place, grub_int64_t offset)
*place |= grub_cpu_to_le32 (val) & ~insmask;
}
/*
* ABS64_LO20 relocation for the 64-bit absolute address
* (*(uint32_t *) PC) [24 ... 5] = (S + A) [51 ... 32]
*/
void grub_loongarch64_abs64_lo20 (grub_uint32_t *place, grub_int64_t offset)
{
const grub_uint32_t insmask = grub_cpu_to_le32_compile_time (0xfe00001f);