coreboot-libre-fam15h-rdimm/3rdparty/opensbi/lib/sbi/riscv_unpriv.c

159 lines
5.4 KiB
C

/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <sbi/riscv_encoding.h>
#include <sbi/riscv_unpriv.h>
#include <sbi/sbi_bits.h>
#include <sbi/sbi_hart.h>
#include <sbi/sbi_scratch.h>
#define DEFINE_UNPRIVILEGED_LOAD_FUNCTION(type, insn, insnlen) \
type load_##type(const type *addr, \
struct sbi_scratch *scratch, \
struct unpriv_trap *trap) \
{ \
register ulong __mstatus asm("a2"); \
type val = 0; \
trap->ilen = insnlen; \
trap->cause = 0; \
trap->tval = 0; \
sbi_hart_set_trap_info(scratch, trap); \
asm volatile( \
"csrrs %0, " STR(CSR_MSTATUS) ", %3\n" \
#insn " %1, %2\n" \
"csrw " STR(CSR_MSTATUS) ", %0" \
: "+&r"(__mstatus), "=&r"(val) \
: "m"(*addr), "r"(MSTATUS_MPRV)); \
sbi_hart_set_trap_info(scratch, NULL); \
return val; \
}
#define DEFINE_UNPRIVILEGED_STORE_FUNCTION(type, insn, insnlen) \
void store_##type(type *addr, type val, \
struct sbi_scratch *scratch, \
struct unpriv_trap *trap) \
{ \
register ulong __mstatus asm("a3"); \
trap->ilen = insnlen; \
trap->cause = 0; \
trap->tval = 0; \
sbi_hart_set_trap_info(scratch, trap); \
asm volatile( \
"csrrs %0, " STR(CSR_MSTATUS) ", %3\n" \
#insn " %1, %2\n" \
"csrw " STR(CSR_MSTATUS) ", %0" \
: "+&r"(__mstatus) \
: "r"(val), "m"(*addr), "r"(MSTATUS_MPRV)); \
sbi_hart_set_trap_info(scratch, NULL); \
}
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(u8, lbu, 4)
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(u16, lhu, 4)
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(s8, lb, 4)
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(s16, lh, 4)
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(s32, lw, 2)
DEFINE_UNPRIVILEGED_STORE_FUNCTION(u8, sb, 4)
DEFINE_UNPRIVILEGED_STORE_FUNCTION(u16, sh, 4)
DEFINE_UNPRIVILEGED_STORE_FUNCTION(u32, sw, 2)
#if __riscv_xlen == 64
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(u32, lwu, 4)
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(u64, ld, 2)
DEFINE_UNPRIVILEGED_STORE_FUNCTION(u64, sd, 2)
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(ulong, ld, 2)
#else
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(u32, lw, 2)
DEFINE_UNPRIVILEGED_LOAD_FUNCTION(ulong, lw, 2)
u64 load_u64(const u64 *addr,
struct sbi_scratch *scratch, struct unpriv_trap *trap)
{
u64 ret = load_u32((u32 *)addr, scratch, trap);
if (trap->cause)
return 0;
ret |= ((u64)load_u32((u32 *)addr + 1, scratch, trap) << 32);
if (trap->cause)
return 0;
return ret;
}
void store_u64(u64 *addr, u64 val,
struct sbi_scratch *scratch, struct unpriv_trap *trap)
{
store_u32((u32 *)addr, val, scratch, trap);
if (trap->cause)
return;
store_u32((u32 *)addr + 1, val >> 32, scratch, trap);
if (trap->cause)
return;
}
#endif
ulong get_insn(ulong mepc, bool virt, struct sbi_scratch *scratch,
struct unpriv_trap *trap)
{
ulong __mstatus = 0, __vsstatus = 0, val = 0;
#ifdef __riscv_compressed
ulong rvc_mask = 3, tmp;
#endif
trap->ilen = 4;
trap->cause = 0;
trap->tval = 0;
sbi_hart_set_trap_info(scratch, trap);
if (virt)
__vsstatus = csr_read_set(CSR_VSSTATUS, SSTATUS_MXR);
#ifndef __riscv_compressed
asm("csrrs %[mstatus], " STR(CSR_MSTATUS) ", %[mprv]\n"
#if __riscv_xlen == 64
STR(LWU) " %[insn], (%[addr])\n"
#else
STR(LW) " %[insn], (%[addr])\n"
#endif
"csrw " STR(CSR_MSTATUS) ", %[mstatus]"
: [mstatus] "+&r"(__mstatus), [insn] "=&r"(val)
: [mprv] "r"(MSTATUS_MPRV | MSTATUS_MXR), [addr] "r"(mepc));
#else
asm("csrrs %[mstatus], " STR(CSR_MSTATUS) ", %[mprv]\n"
"lhu %[insn], (%[addr])\n"
"and %[tmp], %[insn], %[rvc_mask]\n"
"bne %[tmp], %[rvc_mask], 2f\n"
"lhu %[tmp], 2(%[addr])\n"
"sll %[tmp], %[tmp], 16\n"
"add %[insn], %[insn], %[tmp]\n"
"2: csrw " STR(CSR_MSTATUS) ", %[mstatus]"
: [mstatus] "+&r"(__mstatus), [insn] "=&r"(val), [tmp] "=&r"(tmp)
: [mprv] "r"(MSTATUS_MPRV | MSTATUS_MXR), [addr] "r"(mepc),
[rvc_mask] "r"(rvc_mask));
#endif
if (virt)
csr_write(CSR_VSSTATUS, __vsstatus);
sbi_hart_set_trap_info(scratch, NULL);
switch (trap->cause) {
case CAUSE_LOAD_ACCESS:
trap->cause = CAUSE_FETCH_ACCESS;
trap->tval = mepc;
break;
case CAUSE_LOAD_PAGE_FAULT:
trap->cause = CAUSE_FETCH_PAGE_FAULT;
trap->tval = mepc;
break;
default:
break;
};
return val;
}