lib: Emulate AMO instructions when Zaamo is not available

The AMO instructions are very critical for Linux so allow low-end
RISC-V implementations without Zaamo to boot Linux by emulating AMO
instructions using Zalrsc when OpenSBI is compiled without Zaamo.

Signed-off-by: Chao-ying Fu <cfu@mips.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Link: https://lore.kernel.org/r/20250519121207.976949-1-apatel@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>
This commit is contained in:
Chao-ying Fu
2025-05-19 17:42:06 +05:30
committed by Anup Patel
parent 017a161788
commit 8a3071222a
6 changed files with 709 additions and 18 deletions

View File

@@ -13,15 +13,14 @@
#include <sbi/sbi_bitops.h>
#include <sbi/sbi_emulate_csr.h>
#include <sbi/sbi_error.h>
#include <sbi/sbi_illegal_atomic.h>
#include <sbi/sbi_illegal_insn.h>
#include <sbi/sbi_pmu.h>
#include <sbi/sbi_trap.h>
#include <sbi/sbi_unpriv.h>
#include <sbi/sbi_console.h>
typedef int (*illegal_insn_func)(ulong insn, struct sbi_trap_regs *regs);
static int truly_illegal_insn(ulong insn, struct sbi_trap_regs *regs)
int truly_illegal_insn(ulong insn, struct sbi_trap_regs *regs)
{
struct sbi_trap_info trap;
@@ -123,7 +122,7 @@ static const illegal_insn_func illegal_insn_table[32] = {
truly_illegal_insn, /* 8 */
truly_illegal_insn, /* 9 */
truly_illegal_insn, /* 10 */
truly_illegal_insn, /* 11 */
sbi_illegal_atomic, /* 11 */
truly_illegal_insn, /* 12 */
truly_illegal_insn, /* 13 */
truly_illegal_insn, /* 14 */