We should write transformed instruction encoding of the trapped
instruction in [m|h]tinst CSR at time of taking trap as defined
by the RISC-V privileged specification v1.12.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
target/riscv/cpu.h | 3 +
target/riscv/cpu_helper.c | 231 +++++++++++++++++++++++++++++++++++++-
target/riscv/instmap.h | 43 +++++++
3 files changed, 271 insertions(+), 6 deletions(-)
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 194a58d760..11726e9031 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -271,6 +271,9 @@ struct CPUArchState {
/* Signals whether the current exception occurred with two-stage address
translation active. */
bool two_stage_lookup;
+ /* Signals whether the current exception occurred while doing two-stage
+ address translation for the VS-stage page table walk. */
+ bool two_stage_indirect_lookup;
target_ulong scounteren;
target_ulong mcounteren;
diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index 16c6045459..62a6762617 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -22,6 +22,7 @@
#include "qemu/main-loop.h"
#include "cpu.h"
#include "exec/exec-all.h"
+#include "instmap.h"
#include "tcg/tcg-op.h"
#include "trace.h"
#include "semihosting/common-semi.h"
@@ -1055,7 +1056,8 @@ restart:
static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
MMUAccessType access_type, bool pmp_violation,
- bool first_stage, bool two_stage)
+ bool first_stage, bool two_stage,
+ bool two_stage_indirect)
{
CPUState *cs = env_cpu(env);
int page_fault_exceptions, vm;
@@ -1105,6 +1107,7 @@ static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
}
env->badaddr = address;
env->two_stage_lookup = two_stage;
+ env->two_stage_indirect_lookup = two_stage_indirect;
}
hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
@@ -1150,6 +1153,7 @@ void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
env->badaddr = addr;
env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
riscv_cpu_two_stage_lookup(mmu_idx);
+ env->two_stage_indirect_lookup = false;
cpu_loop_exit_restore(cs, retaddr);
}
@@ -1175,6 +1179,7 @@ void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
env->badaddr = addr;
env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
riscv_cpu_two_stage_lookup(mmu_idx);
+ env->two_stage_indirect_lookup = false;
cpu_loop_exit_restore(cs, retaddr);
}
@@ -1190,6 +1195,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
bool pmp_violation = false;
bool first_stage_error = true;
bool two_stage_lookup = false;
+ bool two_stage_indirect_error = false;
int ret = TRANSLATE_FAIL;
int mode = mmu_idx;
/* default TLB page size */
@@ -1227,6 +1233,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
*/
if (ret == TRANSLATE_G_STAGE_FAIL) {
first_stage_error = false;
+ two_stage_indirect_error = true;
access_type = MMU_DATA_LOAD;
}
@@ -1310,12 +1317,207 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
raise_mmu_exception(env, address, access_type, pmp_violation,
first_stage_error,
riscv_cpu_virt_enabled(env) ||
- riscv_cpu_two_stage_lookup(mmu_idx));
+ riscv_cpu_two_stage_lookup(mmu_idx),
+ two_stage_indirect_error);
cpu_loop_exit_restore(cs, retaddr);
}
return true;
}
+
+static target_ulong riscv_transformed_insn(CPURISCVState *env,
+ target_ulong insn)
+{
+ bool xinsn_has_addr_offset = false;
+ target_ulong xinsn = 0;
+
+ /*
+ * Only Quadrant 0 and Quadrant 2 of RVC instruction space need to
+ * be uncompressed. The Quadrant 1 of RVC instruction space need
+ * not be transformed because these instructions won't generate
+ * any load/store trap.
+ */
+
+ if ((insn & 0x3) != 0x3) {
+ /* Transform 16bit instruction into 32bit instruction */
+ switch (GET_C_OP(insn)) {
+ case OPC_RISC_C_OP_QUAD0: /* Quadrant 0 */
+ switch (GET_C_FUNC(insn)) {
+ case OPC_RISC_C_FUNC_FLD_LQ:
+ if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
+ xinsn = OPC_RISC_FLD;
+ xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ case OPC_RISC_C_FUNC_LW: /* C.LW */
+ xinsn = OPC_RISC_LW;
+ xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_I_IMM(xinsn, GET_C_LW_IMM(insn));
+ xinsn_has_addr_offset = true;
+ break;
+ case OPC_RISC_C_FUNC_FLW_LD:
+ if (riscv_cpu_xlen(env) == 32) { /* C.FLW (RV32) */
+ xinsn = OPC_RISC_FLW;
+ xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_I_IMM(xinsn, GET_C_LW_IMM(insn));
+ xinsn_has_addr_offset = true;
+ } else { /* C.LD (RV64/RV128) */
+ xinsn = OPC_RISC_LD;
+ xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ case OPC_RISC_C_FUNC_FSD_SQ:
+ if (riscv_cpu_xlen(env) != 128) { /* C.FSD (RV32/64) */
+ xinsn = OPC_RISC_FSD;
+ xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_S_IMM(xinsn, GET_C_SD_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ case OPC_RISC_C_FUNC_SW: /* C.SW */
+ xinsn = OPC_RISC_SW;
+ xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_S_IMM(xinsn, GET_C_SW_IMM(insn));
+ xinsn_has_addr_offset = true;
+ break;
+ case OPC_RISC_C_FUNC_FSW_SD:
+ if (riscv_cpu_xlen(env) == 32) { /* C.FSW (RV32) */
+ xinsn = OPC_RISC_FSW;
+ xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_S_IMM(xinsn, GET_C_SW_IMM(insn));
+ xinsn_has_addr_offset = true;
+ } else { /* C.SD (RV64/RV128) */
+ xinsn = OPC_RISC_SD;
+ xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
+ xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
+ xinsn = SET_S_IMM(xinsn, GET_C_SD_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ default:
+ break;
+ }
+ break;
+ case OPC_RISC_C_OP_QUAD2: /* Quadrant 2 */
+ switch (GET_C_FUNC(insn)) {
+ case OPC_RISC_C_FUNC_FLDSP_LQSP:
+ if (riscv_cpu_xlen(env) != 128) { /* C.FLDSP (RV32/64) */
+ xinsn = OPC_RISC_FLD;
+ xinsn = SET_RD(xinsn, GET_C_RD(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_I_IMM(xinsn, GET_C_LDSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ case OPC_RISC_C_FUNC_LWSP: /* C.LWSP */
+ xinsn = OPC_RISC_LW;
+ xinsn = SET_RD(xinsn, GET_C_RD(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_I_IMM(xinsn, GET_C_LWSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ break;
+ case OPC_RISC_C_FUNC_FLWSP_LDSP:
+ if (riscv_cpu_xlen(env) == 32) { /* C.FLWSP (RV32) */
+ xinsn = OPC_RISC_FLW;
+ xinsn = SET_RD(xinsn, GET_C_RD(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_I_IMM(xinsn, GET_C_LWSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ } else { /* C.LDSP (RV64/RV128) */
+ xinsn = OPC_RISC_LD;
+ xinsn = SET_RD(xinsn, GET_C_RD(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_I_IMM(xinsn, GET_C_LDSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ case OPC_RISC_C_FUNC_FSDSP_SQSP:
+ if (riscv_cpu_xlen(env) != 128) { /* C.FSDSP (RV32/64) */
+ xinsn = OPC_RISC_FSD;
+ xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_S_IMM(xinsn, GET_C_SDSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ case OPC_RISC_C_FUNC_SWSP: /* C.SWSP */
+ xinsn = OPC_RISC_SW;
+ xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_S_IMM(xinsn, GET_C_SWSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ break;
+ case 7:
+ if (riscv_cpu_xlen(env) == 32) { /* C.FSWSP (RV32) */
+ xinsn = OPC_RISC_FSW;
+ xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_S_IMM(xinsn, GET_C_SWSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ } else { /* C.SDSP (RV64/RV128) */
+ xinsn = OPC_RISC_SD;
+ xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
+ xinsn = SET_RS1(xinsn, 2);
+ xinsn = SET_S_IMM(xinsn, GET_C_SDSP_IMM(insn));
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+
+ /*
+ * Clear Bit1 of transformed instruction to indicate that
+ * original insruction was a 16bit instruction
+ */
+ xinsn &= ~((target_ulong)0x2);
+ } else {
+ /* No need to transform 32bit (or wider) instructions */
+ xinsn = insn;
+
+ /* Check for instructions which need address offset */
+ switch (MASK_OP_MAJOR(insn)) {
+ case OPC_RISC_LOAD:
+ case OPC_RISC_STORE:
+ case OPC_RISC_ATOMIC:
+ case OPC_RISC_FP_LOAD:
+ case OPC_RISC_FP_STORE:
+ xinsn_has_addr_offset = true;
+ break;
+ case OPC_RISC_SYSTEM:
+ if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
+ xinsn_has_addr_offset = true;
+ }
+ break;
+ }
+ }
+
+ if (xinsn_has_addr_offset) {
+ /*
+ * The "Addr. Offset" field in transformed instruction is non-zero
+ * only for misaligned load/store traps which are very unlikely on
+ * QEMU so for now always set "Addr. Offset" to zero.
+ */
+ xinsn = SET_RS1(xinsn, 0);
+ }
+
+ return xinsn;
+}
#endif /* !CONFIG_USER_ONLY */
/*
@@ -1340,6 +1542,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
uint64_t deleg = async ? env->mideleg : env->medeleg;
target_ulong tval = 0;
+ target_ulong tinst = 0;
target_ulong htval = 0;
target_ulong mtval2 = 0;
@@ -1355,18 +1558,31 @@ void riscv_cpu_do_interrupt(CPUState *cs)
if (!async) {
/* set tval to badaddr for traps with address information */
switch (cause) {
- case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
- case RISCV_EXCP_INST_ADDR_MIS:
- case RISCV_EXCP_INST_ACCESS_FAULT:
case RISCV_EXCP_LOAD_ADDR_MIS:
case RISCV_EXCP_STORE_AMO_ADDR_MIS:
case RISCV_EXCP_LOAD_ACCESS_FAULT:
case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
- case RISCV_EXCP_INST_PAGE_FAULT:
case RISCV_EXCP_LOAD_PAGE_FAULT:
case RISCV_EXCP_STORE_PAGE_FAULT:
+ write_gva = env->two_stage_lookup;
+ tval = env->badaddr;
+ if (env->two_stage_indirect_lookup) {
+ /*
+ * special pseudoinstruction for G-stage fault taken while
+ * doing VS-stage page table walk.
+ */
+ tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
+ } else {
+ /* transformed instruction for all other load/store faults */
+ tinst = riscv_transformed_insn(env, env->bins);
+ }
+ break;
+ case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
+ case RISCV_EXCP_INST_ADDR_MIS:
+ case RISCV_EXCP_INST_ACCESS_FAULT:
+ case RISCV_EXCP_INST_PAGE_FAULT:
write_gva = env->two_stage_lookup;
tval = env->badaddr;
break;
@@ -1448,6 +1664,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
env->sepc = env->pc;
env->stval = tval;
env->htval = htval;
+ env->htinst = tinst;
env->pc = (env->stvec >> 2 << 2) +
((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
riscv_cpu_set_mode(env, PRV_S);
@@ -1478,6 +1695,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
env->mepc = env->pc;
env->mtval = tval;
env->mtval2 = mtval2;
+ env->mtinst = tinst;
env->pc = (env->mtvec >> 2 << 2) +
((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
riscv_cpu_set_mode(env, PRV_M);
@@ -1490,6 +1708,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
*/
env->two_stage_lookup = false;
+ env->two_stage_indirect_lookup = false;
#endif
cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */
}
diff --git a/target/riscv/instmap.h b/target/riscv/instmap.h
index 40b6d2b64d..f564a69d90 100644
--- a/target/riscv/instmap.h
+++ b/target/riscv/instmap.h
@@ -184,6 +184,8 @@ enum {
OPC_RISC_CSRRWI = OPC_RISC_SYSTEM | (0x5 << 12),
OPC_RISC_CSRRSI = OPC_RISC_SYSTEM | (0x6 << 12),
OPC_RISC_CSRRCI = OPC_RISC_SYSTEM | (0x7 << 12),
+
+ OPC_RISC_HLVHSV = OPC_RISC_SYSTEM | (0x4 << 12),
};
#define MASK_OP_FP_LOAD(op) (MASK_OP_MAJOR(op) | (op & (0x7 << 12)))
@@ -316,6 +318,12 @@ enum {
#define GET_RS2(inst) extract32(inst, 20, 5)
#define GET_RD(inst) extract32(inst, 7, 5)
#define GET_IMM(inst) sextract64(inst, 20, 12)
+#define SET_RS1(inst, val) deposit32(inst, 15, 5, val)
+#define SET_RS2(inst, val) deposit32(inst, 20, 5, val)
+#define SET_RD(inst, val) deposit32(inst, 7, 5, val)
+#define SET_I_IMM(inst, val) deposit32(inst, 20, 12, val)
+#define SET_S_IMM(inst, val) \
+ deposit32(deposit32(inst, 7, 5, val), 25, 7, (val) >> 5)
/* RVC decoding macros */
#define GET_C_IMM(inst) (extract32(inst, 2, 5) \
@@ -346,6 +354,8 @@ enum {
| (extract32(inst, 5, 1) << 6))
#define GET_C_LD_IMM(inst) ((extract16(inst, 10, 3) << 3) \
| (extract16(inst, 5, 2) << 6))
+#define GET_C_SW_IMM(inst) GET_C_LW_IMM(inst)
+#define GET_C_SD_IMM(inst) GET_C_LD_IMM(inst)
#define GET_C_J_IMM(inst) ((extract32(inst, 3, 3) << 1) \
| (extract32(inst, 11, 1) << 4) \
| (extract32(inst, 2, 1) << 5) \
@@ -366,4 +376,37 @@ enum {
#define GET_C_RS1S(inst) (8 + extract16(inst, 7, 3))
#define GET_C_RS2S(inst) (8 + extract16(inst, 2, 3))
+#define GET_C_FUNC(inst) extract32(inst, 13, 3)
+#define GET_C_OP(inst) extract32(inst, 0, 2)
+
+enum {
+ /* RVC Quadrants */
+ OPC_RISC_C_OP_QUAD0 = 0x0,
+ OPC_RISC_C_OP_QUAD1 = 0x1,
+ OPC_RISC_C_OP_QUAD2 = 0x2
+};
+
+enum {
+ /* RVC Quadrant 0 */
+ OPC_RISC_C_FUNC_ADDI4SPN = 0x0,
+ OPC_RISC_C_FUNC_FLD_LQ = 0x1,
+ OPC_RISC_C_FUNC_LW = 0x2,
+ OPC_RISC_C_FUNC_FLW_LD = 0x3,
+ OPC_RISC_C_FUNC_FSD_SQ = 0x5,
+ OPC_RISC_C_FUNC_SW = 0x6,
+ OPC_RISC_C_FUNC_FSW_SD = 0x7
+};
+
+enum {
+ /* RVC Quadrant 2 */
+ OPC_RISC_C_FUNC_SLLI_SLLI64 = 0x0,
+ OPC_RISC_C_FUNC_FLDSP_LQSP = 0x1,
+ OPC_RISC_C_FUNC_LWSP = 0x2,
+ OPC_RISC_C_FUNC_FLWSP_LDSP = 0x3,
+ OPC_RISC_C_FUNC_JR_MV_EBREAK_JALR_ADD = 0x4,
+ OPC_RISC_C_FUNC_FSDSP_SQSP = 0x5,
+ OPC_RISC_C_FUNC_SWSP = 0x6,
+ OPC_RISC_C_FUNC_FSWSP_SDSP = 0x7
+};
+
#endif
--
2.34.1On Thu, Jun 9, 2022 at 1:31 PM Anup Patel <apatel@ventanamicro.com> wrote:
>
> We should write transformed instruction encoding of the trapped
> instruction in [m|h]tinst CSR at time of taking trap as defined
> by the RISC-V privileged specification v1.12.
>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
This fails to pass checkpatch
ERROR: suspect code indent for conditional statements (13, 17)
#257: FILE: target/riscv/cpu_helper.c:1480:
+ if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
+ xinsn = insn;
total: 1 errors, 0 warnings, 389 lines checked
Alistair
> ---
> target/riscv/cpu.h | 3 +
> target/riscv/cpu_helper.c | 231 +++++++++++++++++++++++++++++++++++++-
> target/riscv/instmap.h | 43 +++++++
> 3 files changed, 271 insertions(+), 6 deletions(-)
>
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index 194a58d760..11726e9031 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -271,6 +271,9 @@ struct CPUArchState {
> /* Signals whether the current exception occurred with two-stage address
> translation active. */
> bool two_stage_lookup;
> + /* Signals whether the current exception occurred while doing two-stage
> + address translation for the VS-stage page table walk. */
> + bool two_stage_indirect_lookup;
>
> target_ulong scounteren;
> target_ulong mcounteren;
> diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
> index 16c6045459..62a6762617 100644
> --- a/target/riscv/cpu_helper.c
> +++ b/target/riscv/cpu_helper.c
> @@ -22,6 +22,7 @@
> #include "qemu/main-loop.h"
> #include "cpu.h"
> #include "exec/exec-all.h"
> +#include "instmap.h"
> #include "tcg/tcg-op.h"
> #include "trace.h"
> #include "semihosting/common-semi.h"
> @@ -1055,7 +1056,8 @@ restart:
>
> static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
> MMUAccessType access_type, bool pmp_violation,
> - bool first_stage, bool two_stage)
> + bool first_stage, bool two_stage,
> + bool two_stage_indirect)
> {
> CPUState *cs = env_cpu(env);
> int page_fault_exceptions, vm;
> @@ -1105,6 +1107,7 @@ static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
> }
> env->badaddr = address;
> env->two_stage_lookup = two_stage;
> + env->two_stage_indirect_lookup = two_stage_indirect;
> }
>
> hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
> @@ -1150,6 +1153,7 @@ void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
> env->badaddr = addr;
> env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
> riscv_cpu_two_stage_lookup(mmu_idx);
> + env->two_stage_indirect_lookup = false;
> cpu_loop_exit_restore(cs, retaddr);
> }
>
> @@ -1175,6 +1179,7 @@ void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
> env->badaddr = addr;
> env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
> riscv_cpu_two_stage_lookup(mmu_idx);
> + env->two_stage_indirect_lookup = false;
> cpu_loop_exit_restore(cs, retaddr);
> }
>
> @@ -1190,6 +1195,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
> bool pmp_violation = false;
> bool first_stage_error = true;
> bool two_stage_lookup = false;
> + bool two_stage_indirect_error = false;
> int ret = TRANSLATE_FAIL;
> int mode = mmu_idx;
> /* default TLB page size */
> @@ -1227,6 +1233,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
> */
> if (ret == TRANSLATE_G_STAGE_FAIL) {
> first_stage_error = false;
> + two_stage_indirect_error = true;
> access_type = MMU_DATA_LOAD;
> }
>
> @@ -1310,12 +1317,207 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
> raise_mmu_exception(env, address, access_type, pmp_violation,
> first_stage_error,
> riscv_cpu_virt_enabled(env) ||
> - riscv_cpu_two_stage_lookup(mmu_idx));
> + riscv_cpu_two_stage_lookup(mmu_idx),
> + two_stage_indirect_error);
> cpu_loop_exit_restore(cs, retaddr);
> }
>
> return true;
> }
> +
> +static target_ulong riscv_transformed_insn(CPURISCVState *env,
> + target_ulong insn)
> +{
> + bool xinsn_has_addr_offset = false;
> + target_ulong xinsn = 0;
> +
> + /*
> + * Only Quadrant 0 and Quadrant 2 of RVC instruction space need to
> + * be uncompressed. The Quadrant 1 of RVC instruction space need
> + * not be transformed because these instructions won't generate
> + * any load/store trap.
> + */
> +
> + if ((insn & 0x3) != 0x3) {
> + /* Transform 16bit instruction into 32bit instruction */
> + switch (GET_C_OP(insn)) {
> + case OPC_RISC_C_OP_QUAD0: /* Quadrant 0 */
> + switch (GET_C_FUNC(insn)) {
> + case OPC_RISC_C_FUNC_FLD_LQ:
> + if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
> + xinsn = OPC_RISC_FLD;
> + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + case OPC_RISC_C_FUNC_LW: /* C.LW */
> + xinsn = OPC_RISC_LW;
> + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_I_IMM(xinsn, GET_C_LW_IMM(insn));
> + xinsn_has_addr_offset = true;
> + break;
> + case OPC_RISC_C_FUNC_FLW_LD:
> + if (riscv_cpu_xlen(env) == 32) { /* C.FLW (RV32) */
> + xinsn = OPC_RISC_FLW;
> + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_I_IMM(xinsn, GET_C_LW_IMM(insn));
> + xinsn_has_addr_offset = true;
> + } else { /* C.LD (RV64/RV128) */
> + xinsn = OPC_RISC_LD;
> + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + case OPC_RISC_C_FUNC_FSD_SQ:
> + if (riscv_cpu_xlen(env) != 128) { /* C.FSD (RV32/64) */
> + xinsn = OPC_RISC_FSD;
> + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_S_IMM(xinsn, GET_C_SD_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + case OPC_RISC_C_FUNC_SW: /* C.SW */
> + xinsn = OPC_RISC_SW;
> + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_S_IMM(xinsn, GET_C_SW_IMM(insn));
> + xinsn_has_addr_offset = true;
> + break;
> + case OPC_RISC_C_FUNC_FSW_SD:
> + if (riscv_cpu_xlen(env) == 32) { /* C.FSW (RV32) */
> + xinsn = OPC_RISC_FSW;
> + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_S_IMM(xinsn, GET_C_SW_IMM(insn));
> + xinsn_has_addr_offset = true;
> + } else { /* C.SD (RV64/RV128) */
> + xinsn = OPC_RISC_SD;
> + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_S_IMM(xinsn, GET_C_SD_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + default:
> + break;
> + }
> + break;
> + case OPC_RISC_C_OP_QUAD2: /* Quadrant 2 */
> + switch (GET_C_FUNC(insn)) {
> + case OPC_RISC_C_FUNC_FLDSP_LQSP:
> + if (riscv_cpu_xlen(env) != 128) { /* C.FLDSP (RV32/64) */
> + xinsn = OPC_RISC_FLD;
> + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_I_IMM(xinsn, GET_C_LDSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + case OPC_RISC_C_FUNC_LWSP: /* C.LWSP */
> + xinsn = OPC_RISC_LW;
> + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_I_IMM(xinsn, GET_C_LWSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + break;
> + case OPC_RISC_C_FUNC_FLWSP_LDSP:
> + if (riscv_cpu_xlen(env) == 32) { /* C.FLWSP (RV32) */
> + xinsn = OPC_RISC_FLW;
> + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_I_IMM(xinsn, GET_C_LWSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + } else { /* C.LDSP (RV64/RV128) */
> + xinsn = OPC_RISC_LD;
> + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_I_IMM(xinsn, GET_C_LDSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + case OPC_RISC_C_FUNC_FSDSP_SQSP:
> + if (riscv_cpu_xlen(env) != 128) { /* C.FSDSP (RV32/64) */
> + xinsn = OPC_RISC_FSD;
> + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_S_IMM(xinsn, GET_C_SDSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + case OPC_RISC_C_FUNC_SWSP: /* C.SWSP */
> + xinsn = OPC_RISC_SW;
> + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_S_IMM(xinsn, GET_C_SWSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + break;
> + case 7:
> + if (riscv_cpu_xlen(env) == 32) { /* C.FSWSP (RV32) */
> + xinsn = OPC_RISC_FSW;
> + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_S_IMM(xinsn, GET_C_SWSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + } else { /* C.SDSP (RV64/RV128) */
> + xinsn = OPC_RISC_SD;
> + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> + xinsn = SET_RS1(xinsn, 2);
> + xinsn = SET_S_IMM(xinsn, GET_C_SDSP_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + /*
> + * Clear Bit1 of transformed instruction to indicate that
> + * original insruction was a 16bit instruction
> + */
> + xinsn &= ~((target_ulong)0x2);
> + } else {
> + /* No need to transform 32bit (or wider) instructions */
> + xinsn = insn;
> +
> + /* Check for instructions which need address offset */
> + switch (MASK_OP_MAJOR(insn)) {
> + case OPC_RISC_LOAD:
> + case OPC_RISC_STORE:
> + case OPC_RISC_ATOMIC:
> + case OPC_RISC_FP_LOAD:
> + case OPC_RISC_FP_STORE:
> + xinsn_has_addr_offset = true;
> + break;
> + case OPC_RISC_SYSTEM:
> + if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
> + xinsn_has_addr_offset = true;
> + }
> + break;
> + }
> + }
> +
> + if (xinsn_has_addr_offset) {
> + /*
> + * The "Addr. Offset" field in transformed instruction is non-zero
> + * only for misaligned load/store traps which are very unlikely on
> + * QEMU so for now always set "Addr. Offset" to zero.
> + */
> + xinsn = SET_RS1(xinsn, 0);
> + }
> +
> + return xinsn;
> +}
> #endif /* !CONFIG_USER_ONLY */
>
> /*
> @@ -1340,6 +1542,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
> uint64_t deleg = async ? env->mideleg : env->medeleg;
> target_ulong tval = 0;
> + target_ulong tinst = 0;
> target_ulong htval = 0;
> target_ulong mtval2 = 0;
>
> @@ -1355,18 +1558,31 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> if (!async) {
> /* set tval to badaddr for traps with address information */
> switch (cause) {
> - case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
> case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
> - case RISCV_EXCP_INST_ADDR_MIS:
> - case RISCV_EXCP_INST_ACCESS_FAULT:
> case RISCV_EXCP_LOAD_ADDR_MIS:
> case RISCV_EXCP_STORE_AMO_ADDR_MIS:
> case RISCV_EXCP_LOAD_ACCESS_FAULT:
> case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
> - case RISCV_EXCP_INST_PAGE_FAULT:
> case RISCV_EXCP_LOAD_PAGE_FAULT:
> case RISCV_EXCP_STORE_PAGE_FAULT:
> + write_gva = env->two_stage_lookup;
> + tval = env->badaddr;
> + if (env->two_stage_indirect_lookup) {
> + /*
> + * special pseudoinstruction for G-stage fault taken while
> + * doing VS-stage page table walk.
> + */
> + tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
> + } else {
> + /* transformed instruction for all other load/store faults */
> + tinst = riscv_transformed_insn(env, env->bins);
> + }
> + break;
> + case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> + case RISCV_EXCP_INST_ADDR_MIS:
> + case RISCV_EXCP_INST_ACCESS_FAULT:
> + case RISCV_EXCP_INST_PAGE_FAULT:
> write_gva = env->two_stage_lookup;
> tval = env->badaddr;
> break;
> @@ -1448,6 +1664,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> env->sepc = env->pc;
> env->stval = tval;
> env->htval = htval;
> + env->htinst = tinst;
> env->pc = (env->stvec >> 2 << 2) +
> ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
> riscv_cpu_set_mode(env, PRV_S);
> @@ -1478,6 +1695,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> env->mepc = env->pc;
> env->mtval = tval;
> env->mtval2 = mtval2;
> + env->mtinst = tinst;
> env->pc = (env->mtvec >> 2 << 2) +
> ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
> riscv_cpu_set_mode(env, PRV_M);
> @@ -1490,6 +1708,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> */
>
> env->two_stage_lookup = false;
> + env->two_stage_indirect_lookup = false;
> #endif
> cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */
> }
> diff --git a/target/riscv/instmap.h b/target/riscv/instmap.h
> index 40b6d2b64d..f564a69d90 100644
> --- a/target/riscv/instmap.h
> +++ b/target/riscv/instmap.h
> @@ -184,6 +184,8 @@ enum {
> OPC_RISC_CSRRWI = OPC_RISC_SYSTEM | (0x5 << 12),
> OPC_RISC_CSRRSI = OPC_RISC_SYSTEM | (0x6 << 12),
> OPC_RISC_CSRRCI = OPC_RISC_SYSTEM | (0x7 << 12),
> +
> + OPC_RISC_HLVHSV = OPC_RISC_SYSTEM | (0x4 << 12),
> };
>
> #define MASK_OP_FP_LOAD(op) (MASK_OP_MAJOR(op) | (op & (0x7 << 12)))
> @@ -316,6 +318,12 @@ enum {
> #define GET_RS2(inst) extract32(inst, 20, 5)
> #define GET_RD(inst) extract32(inst, 7, 5)
> #define GET_IMM(inst) sextract64(inst, 20, 12)
> +#define SET_RS1(inst, val) deposit32(inst, 15, 5, val)
> +#define SET_RS2(inst, val) deposit32(inst, 20, 5, val)
> +#define SET_RD(inst, val) deposit32(inst, 7, 5, val)
> +#define SET_I_IMM(inst, val) deposit32(inst, 20, 12, val)
> +#define SET_S_IMM(inst, val) \
> + deposit32(deposit32(inst, 7, 5, val), 25, 7, (val) >> 5)
>
> /* RVC decoding macros */
> #define GET_C_IMM(inst) (extract32(inst, 2, 5) \
> @@ -346,6 +354,8 @@ enum {
> | (extract32(inst, 5, 1) << 6))
> #define GET_C_LD_IMM(inst) ((extract16(inst, 10, 3) << 3) \
> | (extract16(inst, 5, 2) << 6))
> +#define GET_C_SW_IMM(inst) GET_C_LW_IMM(inst)
> +#define GET_C_SD_IMM(inst) GET_C_LD_IMM(inst)
> #define GET_C_J_IMM(inst) ((extract32(inst, 3, 3) << 1) \
> | (extract32(inst, 11, 1) << 4) \
> | (extract32(inst, 2, 1) << 5) \
> @@ -366,4 +376,37 @@ enum {
> #define GET_C_RS1S(inst) (8 + extract16(inst, 7, 3))
> #define GET_C_RS2S(inst) (8 + extract16(inst, 2, 3))
>
> +#define GET_C_FUNC(inst) extract32(inst, 13, 3)
> +#define GET_C_OP(inst) extract32(inst, 0, 2)
> +
> +enum {
> + /* RVC Quadrants */
> + OPC_RISC_C_OP_QUAD0 = 0x0,
> + OPC_RISC_C_OP_QUAD1 = 0x1,
> + OPC_RISC_C_OP_QUAD2 = 0x2
> +};
> +
> +enum {
> + /* RVC Quadrant 0 */
> + OPC_RISC_C_FUNC_ADDI4SPN = 0x0,
> + OPC_RISC_C_FUNC_FLD_LQ = 0x1,
> + OPC_RISC_C_FUNC_LW = 0x2,
> + OPC_RISC_C_FUNC_FLW_LD = 0x3,
> + OPC_RISC_C_FUNC_FSD_SQ = 0x5,
> + OPC_RISC_C_FUNC_SW = 0x6,
> + OPC_RISC_C_FUNC_FSW_SD = 0x7
> +};
> +
> +enum {
> + /* RVC Quadrant 2 */
> + OPC_RISC_C_FUNC_SLLI_SLLI64 = 0x0,
> + OPC_RISC_C_FUNC_FLDSP_LQSP = 0x1,
> + OPC_RISC_C_FUNC_LWSP = 0x2,
> + OPC_RISC_C_FUNC_FLWSP_LDSP = 0x3,
> + OPC_RISC_C_FUNC_JR_MV_EBREAK_JALR_ADD = 0x4,
> + OPC_RISC_C_FUNC_FSDSP_SQSP = 0x5,
> + OPC_RISC_C_FUNC_SWSP = 0x6,
> + OPC_RISC_C_FUNC_FSWSP_SDSP = 0x7
> +};
> +
> #endif
> --
> 2.34.1
>
>
On Tue, Jun 28, 2022 at 4:48 AM Alistair Francis <alistair23@gmail.com> wrote:
>
> On Thu, Jun 9, 2022 at 1:31 PM Anup Patel <apatel@ventanamicro.com> wrote:
> >
> > We should write transformed instruction encoding of the trapped
> > instruction in [m|h]tinst CSR at time of taking trap as defined
> > by the RISC-V privileged specification v1.12.
> >
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
>
> This fails to pass checkpatch
>
> ERROR: suspect code indent for conditional statements (13, 17)
> #257: FILE: target/riscv/cpu_helper.c:1480:
> + if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
> + xinsn = insn;
>
> total: 1 errors, 0 warnings, 389 lines checked
Okay, I will quickly send v7.
Regards,
Anup
>
> Alistair
>
> > ---
> > target/riscv/cpu.h | 3 +
> > target/riscv/cpu_helper.c | 231 +++++++++++++++++++++++++++++++++++++-
> > target/riscv/instmap.h | 43 +++++++
> > 3 files changed, 271 insertions(+), 6 deletions(-)
> >
> > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> > index 194a58d760..11726e9031 100644
> > --- a/target/riscv/cpu.h
> > +++ b/target/riscv/cpu.h
> > @@ -271,6 +271,9 @@ struct CPUArchState {
> > /* Signals whether the current exception occurred with two-stage address
> > translation active. */
> > bool two_stage_lookup;
> > + /* Signals whether the current exception occurred while doing two-stage
> > + address translation for the VS-stage page table walk. */
> > + bool two_stage_indirect_lookup;
> >
> > target_ulong scounteren;
> > target_ulong mcounteren;
> > diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
> > index 16c6045459..62a6762617 100644
> > --- a/target/riscv/cpu_helper.c
> > +++ b/target/riscv/cpu_helper.c
> > @@ -22,6 +22,7 @@
> > #include "qemu/main-loop.h"
> > #include "cpu.h"
> > #include "exec/exec-all.h"
> > +#include "instmap.h"
> > #include "tcg/tcg-op.h"
> > #include "trace.h"
> > #include "semihosting/common-semi.h"
> > @@ -1055,7 +1056,8 @@ restart:
> >
> > static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
> > MMUAccessType access_type, bool pmp_violation,
> > - bool first_stage, bool two_stage)
> > + bool first_stage, bool two_stage,
> > + bool two_stage_indirect)
> > {
> > CPUState *cs = env_cpu(env);
> > int page_fault_exceptions, vm;
> > @@ -1105,6 +1107,7 @@ static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
> > }
> > env->badaddr = address;
> > env->two_stage_lookup = two_stage;
> > + env->two_stage_indirect_lookup = two_stage_indirect;
> > }
> >
> > hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
> > @@ -1150,6 +1153,7 @@ void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
> > env->badaddr = addr;
> > env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
> > riscv_cpu_two_stage_lookup(mmu_idx);
> > + env->two_stage_indirect_lookup = false;
> > cpu_loop_exit_restore(cs, retaddr);
> > }
> >
> > @@ -1175,6 +1179,7 @@ void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
> > env->badaddr = addr;
> > env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
> > riscv_cpu_two_stage_lookup(mmu_idx);
> > + env->two_stage_indirect_lookup = false;
> > cpu_loop_exit_restore(cs, retaddr);
> > }
> >
> > @@ -1190,6 +1195,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
> > bool pmp_violation = false;
> > bool first_stage_error = true;
> > bool two_stage_lookup = false;
> > + bool two_stage_indirect_error = false;
> > int ret = TRANSLATE_FAIL;
> > int mode = mmu_idx;
> > /* default TLB page size */
> > @@ -1227,6 +1233,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
> > */
> > if (ret == TRANSLATE_G_STAGE_FAIL) {
> > first_stage_error = false;
> > + two_stage_indirect_error = true;
> > access_type = MMU_DATA_LOAD;
> > }
> >
> > @@ -1310,12 +1317,207 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
> > raise_mmu_exception(env, address, access_type, pmp_violation,
> > first_stage_error,
> > riscv_cpu_virt_enabled(env) ||
> > - riscv_cpu_two_stage_lookup(mmu_idx));
> > + riscv_cpu_two_stage_lookup(mmu_idx),
> > + two_stage_indirect_error);
> > cpu_loop_exit_restore(cs, retaddr);
> > }
> >
> > return true;
> > }
> > +
> > +static target_ulong riscv_transformed_insn(CPURISCVState *env,
> > + target_ulong insn)
> > +{
> > + bool xinsn_has_addr_offset = false;
> > + target_ulong xinsn = 0;
> > +
> > + /*
> > + * Only Quadrant 0 and Quadrant 2 of RVC instruction space need to
> > + * be uncompressed. The Quadrant 1 of RVC instruction space need
> > + * not be transformed because these instructions won't generate
> > + * any load/store trap.
> > + */
> > +
> > + if ((insn & 0x3) != 0x3) {
> > + /* Transform 16bit instruction into 32bit instruction */
> > + switch (GET_C_OP(insn)) {
> > + case OPC_RISC_C_OP_QUAD0: /* Quadrant 0 */
> > + switch (GET_C_FUNC(insn)) {
> > + case OPC_RISC_C_FUNC_FLD_LQ:
> > + if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
> > + xinsn = OPC_RISC_FLD;
> > + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + case OPC_RISC_C_FUNC_LW: /* C.LW */
> > + xinsn = OPC_RISC_LW;
> > + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_I_IMM(xinsn, GET_C_LW_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + break;
> > + case OPC_RISC_C_FUNC_FLW_LD:
> > + if (riscv_cpu_xlen(env) == 32) { /* C.FLW (RV32) */
> > + xinsn = OPC_RISC_FLW;
> > + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_I_IMM(xinsn, GET_C_LW_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + } else { /* C.LD (RV64/RV128) */
> > + xinsn = OPC_RISC_LD;
> > + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + case OPC_RISC_C_FUNC_FSD_SQ:
> > + if (riscv_cpu_xlen(env) != 128) { /* C.FSD (RV32/64) */
> > + xinsn = OPC_RISC_FSD;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_S_IMM(xinsn, GET_C_SD_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + case OPC_RISC_C_FUNC_SW: /* C.SW */
> > + xinsn = OPC_RISC_SW;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_S_IMM(xinsn, GET_C_SW_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + break;
> > + case OPC_RISC_C_FUNC_FSW_SD:
> > + if (riscv_cpu_xlen(env) == 32) { /* C.FSW (RV32) */
> > + xinsn = OPC_RISC_FSW;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_S_IMM(xinsn, GET_C_SW_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + } else { /* C.SD (RV64/RV128) */
> > + xinsn = OPC_RISC_SD;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_S_IMM(xinsn, GET_C_SD_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + default:
> > + break;
> > + }
> > + break;
> > + case OPC_RISC_C_OP_QUAD2: /* Quadrant 2 */
> > + switch (GET_C_FUNC(insn)) {
> > + case OPC_RISC_C_FUNC_FLDSP_LQSP:
> > + if (riscv_cpu_xlen(env) != 128) { /* C.FLDSP (RV32/64) */
> > + xinsn = OPC_RISC_FLD;
> > + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_I_IMM(xinsn, GET_C_LDSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + case OPC_RISC_C_FUNC_LWSP: /* C.LWSP */
> > + xinsn = OPC_RISC_LW;
> > + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_I_IMM(xinsn, GET_C_LWSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + break;
> > + case OPC_RISC_C_FUNC_FLWSP_LDSP:
> > + if (riscv_cpu_xlen(env) == 32) { /* C.FLWSP (RV32) */
> > + xinsn = OPC_RISC_FLW;
> > + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_I_IMM(xinsn, GET_C_LWSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + } else { /* C.LDSP (RV64/RV128) */
> > + xinsn = OPC_RISC_LD;
> > + xinsn = SET_RD(xinsn, GET_C_RD(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_I_IMM(xinsn, GET_C_LDSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + case OPC_RISC_C_FUNC_FSDSP_SQSP:
> > + if (riscv_cpu_xlen(env) != 128) { /* C.FSDSP (RV32/64) */
> > + xinsn = OPC_RISC_FSD;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_S_IMM(xinsn, GET_C_SDSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + case OPC_RISC_C_FUNC_SWSP: /* C.SWSP */
> > + xinsn = OPC_RISC_SW;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_S_IMM(xinsn, GET_C_SWSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + break;
> > + case 7:
> > + if (riscv_cpu_xlen(env) == 32) { /* C.FSWSP (RV32) */
> > + xinsn = OPC_RISC_FSW;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_S_IMM(xinsn, GET_C_SWSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + } else { /* C.SDSP (RV64/RV128) */
> > + xinsn = OPC_RISC_SD;
> > + xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
> > + xinsn = SET_RS1(xinsn, 2);
> > + xinsn = SET_S_IMM(xinsn, GET_C_SDSP_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + default:
> > + break;
> > + }
> > + break;
> > + default:
> > + break;
> > + }
> > +
> > + /*
> > + * Clear Bit1 of transformed instruction to indicate that
> > + * original insruction was a 16bit instruction
> > + */
> > + xinsn &= ~((target_ulong)0x2);
> > + } else {
> > + /* No need to transform 32bit (or wider) instructions */
> > + xinsn = insn;
> > +
> > + /* Check for instructions which need address offset */
> > + switch (MASK_OP_MAJOR(insn)) {
> > + case OPC_RISC_LOAD:
> > + case OPC_RISC_STORE:
> > + case OPC_RISC_ATOMIC:
> > + case OPC_RISC_FP_LOAD:
> > + case OPC_RISC_FP_STORE:
> > + xinsn_has_addr_offset = true;
> > + break;
> > + case OPC_RISC_SYSTEM:
> > + if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
> > + }
> > + }
> > +
> > + if (xinsn_has_addr_offset) {
> > + /*
> > + * The "Addr. Offset" field in transformed instruction is non-zero
> > + * only for misaligned load/store traps which are very unlikely on
> > + * QEMU so for now always set "Addr. Offset" to zero.
> > + */
> > + xinsn = SET_RS1(xinsn, 0);
> > + }
> > +
> > + return xinsn;
> > +}
> > #endif /* !CONFIG_USER_ONLY */
> >
> > /*
> > @@ -1340,6 +1542,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
> > uint64_t deleg = async ? env->mideleg : env->medeleg;
> > target_ulong tval = 0;
> > + target_ulong tinst = 0;
> > target_ulong htval = 0;
> > target_ulong mtval2 = 0;
> >
> > @@ -1355,18 +1558,31 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > if (!async) {
> > /* set tval to badaddr for traps with address information */
> > switch (cause) {
> > - case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> > case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
> > case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
> > - case RISCV_EXCP_INST_ADDR_MIS:
> > - case RISCV_EXCP_INST_ACCESS_FAULT:
> > case RISCV_EXCP_LOAD_ADDR_MIS:
> > case RISCV_EXCP_STORE_AMO_ADDR_MIS:
> > case RISCV_EXCP_LOAD_ACCESS_FAULT:
> > case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
> > - case RISCV_EXCP_INST_PAGE_FAULT:
> > case RISCV_EXCP_LOAD_PAGE_FAULT:
> > case RISCV_EXCP_STORE_PAGE_FAULT:
> > + write_gva = env->two_stage_lookup;
> > + tval = env->badaddr;
> > + if (env->two_stage_indirect_lookup) {
> > + /*
> > + * special pseudoinstruction for G-stage fault taken while
> > + * doing VS-stage page table walk.
> > + */
> > + tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
> > + } else {
> > + /* transformed instruction for all other load/store faults */
> > + tinst = riscv_transformed_insn(env, env->bins);
> > + }
> > + break;
> > + case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> > + case RISCV_EXCP_INST_ADDR_MIS:
> > + case RISCV_EXCP_INST_ACCESS_FAULT:
> > + case RISCV_EXCP_INST_PAGE_FAULT:
> > write_gva = env->two_stage_lookup;
> > tval = env->badaddr;
> > break;
> > @@ -1448,6 +1664,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > env->sepc = env->pc;
> > env->stval = tval;
> > env->htval = htval;
> > + env->htinst = tinst;
> > env->pc = (env->stvec >> 2 << 2) +
> > ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
> > riscv_cpu_set_mode(env, PRV_S);
> > @@ -1478,6 +1695,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > env->mepc = env->pc;
> > env->mtval = tval;
> > env->mtval2 = mtval2;
> > + env->mtinst = tinst;
> > env->pc = (env->mtvec >> 2 << 2) +
> > ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
> > riscv_cpu_set_mode(env, PRV_M);
> > @@ -1490,6 +1708,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > */
> >
> > env->two_stage_lookup = false;
> > + env->two_stage_indirect_lookup = false;
> > #endif
> > cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */
> > }
> > diff --git a/target/riscv/instmap.h b/target/riscv/instmap.h
> > index 40b6d2b64d..f564a69d90 100644
> > --- a/target/riscv/instmap.h
> > +++ b/target/riscv/instmap.h
> > @@ -184,6 +184,8 @@ enum {
> > OPC_RISC_CSRRWI = OPC_RISC_SYSTEM | (0x5 << 12),
> > OPC_RISC_CSRRSI = OPC_RISC_SYSTEM | (0x6 << 12),
> > OPC_RISC_CSRRCI = OPC_RISC_SYSTEM | (0x7 << 12),
> > +
> > + OPC_RISC_HLVHSV = OPC_RISC_SYSTEM | (0x4 << 12),
> > };
> >
> > #define MASK_OP_FP_LOAD(op) (MASK_OP_MAJOR(op) | (op & (0x7 << 12)))
> > @@ -316,6 +318,12 @@ enum {
> > #define GET_RS2(inst) extract32(inst, 20, 5)
> > #define GET_RD(inst) extract32(inst, 7, 5)
> > #define GET_IMM(inst) sextract64(inst, 20, 12)
> > +#define SET_RS1(inst, val) deposit32(inst, 15, 5, val)
> > +#define SET_RS2(inst, val) deposit32(inst, 20, 5, val)
> > +#define SET_RD(inst, val) deposit32(inst, 7, 5, val)
> > +#define SET_I_IMM(inst, val) deposit32(inst, 20, 12, val)
> > +#define SET_S_IMM(inst, val) \
> > + deposit32(deposit32(inst, 7, 5, val), 25, 7, (val) >> 5)
> >
> > /* RVC decoding macros */
> > #define GET_C_IMM(inst) (extract32(inst, 2, 5) \
> > @@ -346,6 +354,8 @@ enum {
> > | (extract32(inst, 5, 1) << 6))
> > #define GET_C_LD_IMM(inst) ((extract16(inst, 10, 3) << 3) \
> > | (extract16(inst, 5, 2) << 6))
> > +#define GET_C_SW_IMM(inst) GET_C_LW_IMM(inst)
> > +#define GET_C_SD_IMM(inst) GET_C_LD_IMM(inst)
> > #define GET_C_J_IMM(inst) ((extract32(inst, 3, 3) << 1) \
> > | (extract32(inst, 11, 1) << 4) \
> > | (extract32(inst, 2, 1) << 5) \
> > @@ -366,4 +376,37 @@ enum {
> > #define GET_C_RS1S(inst) (8 + extract16(inst, 7, 3))
> > #define GET_C_RS2S(inst) (8 + extract16(inst, 2, 3))
> >
> > +#define GET_C_FUNC(inst) extract32(inst, 13, 3)
> > +#define GET_C_OP(inst) extract32(inst, 0, 2)
> > +
> > +enum {
> > + /* RVC Quadrants */
> > + OPC_RISC_C_OP_QUAD0 = 0x0,
> > + OPC_RISC_C_OP_QUAD1 = 0x1,
> > + OPC_RISC_C_OP_QUAD2 = 0x2
> > +};
> > +
> > +enum {
> > + /* RVC Quadrant 0 */
> > + OPC_RISC_C_FUNC_ADDI4SPN = 0x0,
> > + OPC_RISC_C_FUNC_FLD_LQ = 0x1,
> > + OPC_RISC_C_FUNC_LW = 0x2,
> > + OPC_RISC_C_FUNC_FLW_LD = 0x3,
> > + OPC_RISC_C_FUNC_FSD_SQ = 0x5,
> > + OPC_RISC_C_FUNC_SW = 0x6,
> > + OPC_RISC_C_FUNC_FSW_SD = 0x7
> > +};
> > +
> > +enum {
> > + /* RVC Quadrant 2 */
> > + OPC_RISC_C_FUNC_SLLI_SLLI64 = 0x0,
> > + OPC_RISC_C_FUNC_FLDSP_LQSP = 0x1,
> > + OPC_RISC_C_FUNC_LWSP = 0x2,
> > + OPC_RISC_C_FUNC_FLWSP_LDSP = 0x3,
> > + OPC_RISC_C_FUNC_JR_MV_EBREAK_JALR_ADD = 0x4,
> > + OPC_RISC_C_FUNC_FSDSP_SQSP = 0x5,
> > + OPC_RISC_C_FUNC_SWSP = 0x6,
> > + OPC_RISC_C_FUNC_FSWSP_SDSP = 0x7
> > +};
> > +
> > #endif
> > --
> > 2.34.1
> >
> >
Hi Anup Patel,
I think there are some misunderstandings of the privileged spec with regards to
[m|h]tinst handling. Here are some possible issues I've found:
> + case OPC_RISC_C_FUNC_FLD_LQ:
> + if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
> + xinsn = OPC_RISC_FLD;
> + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> + xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
> + xinsn_has_addr_offset = true;
> + }
> + break;
The privileged spec requires that 'for basic loads and stores, the
transformations replace the instruction’s immediate offset fields with zero',
so this SET_I_IMM() line isn't necessary. Similarly for all the compressed
instruction cases, the SET_I_IMM() and SET_S_IMM() calls are all unnecessary.
> + } else {
> + /* No need to transform 32bit (or wider) instructions */
> + xinsn = insn;
For AMO, lr, sc, and hypervisor load/store instructions, this is fine. But as
above, 32-bit integer load/store instructions and floating point load/store
instructions need have their immediate fields cleared to zero.
In addition, the various V-extension vector load/store instructions do not have
defined transformations, so they should show up in [m|h]tinst as all zeros.
> + if (xinsn_has_addr_offset) {
> + /*
> + * The "Addr. Offset" field in transformed instruction is non-zero
> + * only for misaligned load/store traps which are very unlikely on
> + * QEMU so for now always set "Addr. Offset" to zero.
> + */
> + xinsn = SET_RS1(xinsn, 0);
> + }
There seems to be two misconceptions here:
Firstly, QEMU *does* raise address misaligned exceptions for misaligned atomic
accesses.
However, if I understood correctly, the address misaligned exceptions are
irrelevant here because 'Addr. Offset' is only non-zero for a misaligned
accesses that faults but *not* due to an address misaligned exception.
For example, if an ld instruction reads 8 bytes starting from 0xa00ffe, and the
page 0xa00000 to 0xa00fff is mapped, but 0xa01000 to 0xa01fff is not, a load
page fault is raised with [m|s]tval = 0xa01000, while the original virtual
address of the access is 0xa00ffe. The 'Addr. Offset' in this case is 2, i.e.
the difference calculated with (0xa01000 - 0xa00ffe). This means that we *do*
have to set 'Addr. Offset' *because* we handle some misaligned load/store
instructions.
> @@ -1355,18 +1558,31 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> if (!async) {
> /* set tval to badaddr for traps with address information */
> switch (cause) {
> - case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
> case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
> - case RISCV_EXCP_INST_ADDR_MIS:
> - case RISCV_EXCP_INST_ACCESS_FAULT:
> case RISCV_EXCP_LOAD_ADDR_MIS:
> case RISCV_EXCP_STORE_AMO_ADDR_MIS:
> case RISCV_EXCP_LOAD_ACCESS_FAULT:
> case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
> - case RISCV_EXCP_INST_PAGE_FAULT:
> case RISCV_EXCP_LOAD_PAGE_FAULT:
> case RISCV_EXCP_STORE_PAGE_FAULT:
> + write_gva = env->two_stage_lookup;
> + tval = env->badaddr;
> + if (env->two_stage_indirect_lookup) {
> + /*
> + * special pseudoinstruction for G-stage fault taken while
> + * doing VS-stage page table walk.
> + */
> + tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
> + } else {
> + /* transformed instruction for all other load/store faults */
> + tinst = riscv_transformed_insn(env, env->bins);
> + }
> + break;
> + case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> + case RISCV_EXCP_INST_ADDR_MIS:
> + case RISCV_EXCP_INST_ACCESS_FAULT:
> + case RISCV_EXCP_INST_PAGE_FAULT:
> write_gva = env->two_stage_lookup;
> tval = env->badaddr;
> break;
Instruction guest-page faults should set [m|h]tinst to one of the
pseudoinstructions if env->two_stage_lookup is true. Otherwise it should set
[m|h]tinst to zero.
In any case, as this seems to be one of the first implementations of
[m|h]tinst, it might be worthwhile to confirm with the spec authors and clarify
any unclear bits before this gets released.
dramforever
On Fri, Jun 10, 2022 at 3:00 PM dramforever <dramforever@live.com> wrote:
>
> Hi Anup Patel,
>
> I think there are some misunderstandings of the privileged spec with regards to
> [m|h]tinst handling. Here are some possible issues I've found:
>
> > + case OPC_RISC_C_FUNC_FLD_LQ:
> > + if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
> > + xinsn = OPC_RISC_FLD;
> > + xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
> > + xinsn = SET_RS1(xinsn, GET_C_RS1S(insn));
> > + xinsn = SET_I_IMM(xinsn, GET_C_LD_IMM(insn));
> > + xinsn_has_addr_offset = true;
> > + }
> > + break;
>
> The privileged spec requires that 'for basic loads and stores, the
> transformations replace the instruction’s immediate offset fields with zero',
> so this SET_I_IMM() line isn't necessary. Similarly for all the compressed
> instruction cases, the SET_I_IMM() and SET_S_IMM() calls are all unnecessary.
Sure, I will update.
>
> > + } else {
> > + /* No need to transform 32bit (or wider) instructions */
> > + xinsn = insn;
>
> For AMO, lr, sc, and hypervisor load/store instructions, this is fine. But as
> above, 32-bit integer load/store instructions and floating point load/store
> instructions need have their immediate fields cleared to zero.
Okay, I will update.
>
> In addition, the various V-extension vector load/store instructions do not have
> defined transformations, so they should show up in [m|h]tinst as all zeros.
Okay, I will update.
>
> > + if (xinsn_has_addr_offset) {
> > + /*
> > + * The "Addr. Offset" field in transformed instruction is non-zero
> > + * only for misaligned load/store traps which are very unlikely on
> > + * QEMU so for now always set "Addr. Offset" to zero.
> > + */
> > + xinsn = SET_RS1(xinsn, 0);
> > + }
>
> There seems to be two misconceptions here:
>
> Firstly, QEMU *does* raise address misaligned exceptions for misaligned atomic
> accesses.
>
> However, if I understood correctly, the address misaligned exceptions are
> irrelevant here because 'Addr. Offset' is only non-zero for a misaligned
> accesses that faults but *not* due to an address misaligned exception.
>
> For example, if an ld instruction reads 8 bytes starting from 0xa00ffe, and the
> page 0xa00000 to 0xa00fff is mapped, but 0xa01000 to 0xa01fff is not, a load
> page fault is raised with [m|s]tval = 0xa01000, while the original virtual
> address of the access is 0xa00ffe. The 'Addr. Offset' in this case is 2, i.e.
> the difference calculated with (0xa01000 - 0xa00ffe). This means that we *do*
> have to set 'Addr. Offset' *because* we handle some misaligned load/store
> instructions.
Well, I am aware of how "Addr. Offset" field is set but I was not aware that
QEMU generates misaligned exception in a specific case (i.e. misaligned
atomic).
I will update this patch to
>
> > @@ -1355,18 +1558,31 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > if (!async) {
> > /* set tval to badaddr for traps with address information */
> > switch (cause) {
> > - case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> > case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
> > case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
> > - case RISCV_EXCP_INST_ADDR_MIS:
> > - case RISCV_EXCP_INST_ACCESS_FAULT:
> > case RISCV_EXCP_LOAD_ADDR_MIS:
> > case RISCV_EXCP_STORE_AMO_ADDR_MIS:
> > case RISCV_EXCP_LOAD_ACCESS_FAULT:
> > case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
> > - case RISCV_EXCP_INST_PAGE_FAULT:
> > case RISCV_EXCP_LOAD_PAGE_FAULT:
> > case RISCV_EXCP_STORE_PAGE_FAULT:
> > + write_gva = env->two_stage_lookup;
> > + tval = env->badaddr;
> > + if (env->two_stage_indirect_lookup) {
> > + /*
> > + * special pseudoinstruction for G-stage fault taken while
> > + * doing VS-stage page table walk.
> > + */
> > + tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
> > + } else {
> > + /* transformed instruction for all other load/store faults */
> > + tinst = riscv_transformed_insn(env, env->bins);
> > + }
> > + break;
> > + case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> > + case RISCV_EXCP_INST_ADDR_MIS:
> > + case RISCV_EXCP_INST_ACCESS_FAULT:
> > + case RISCV_EXCP_INST_PAGE_FAULT:
> > write_gva = env->two_stage_lookup;
> > tval = env->badaddr;
> > break;
>
> Instruction guest-page faults should set [m|h]tinst to one of the
> pseudoinstructions if env->two_stage_lookup is true. Otherwise it should set
> [m|h]tinst to zero.
>
> In any case, as this seems to be one of the first implementations of
> [m|h]tinst, it might be worthwhile to confirm with the spec authors and clarify
> any unclear bits before this gets released.
This is already handled because tinst is initialized to zero.
Regards,
Anup
>
> dramforever
>
>> In addition, the various V-extension vector load/store instructions do not have
>> defined transformations, so they should show up in [m|h]tinst as all zeros.
> Okay, I will update.
Just a clarification/suggestion: It might be easier to only write non-zero for
instructions with currently defined transformation. Writing zero is always
legal, but writing an undefined transformed instruction is not.
>>> @@ -1355,18 +1558,31 @@ void riscv_cpu_do_interrupt(CPUState *cs)
>>> if (!async) {
>>> /* set tval to badaddr for traps with address information */
>>> switch (cause) {
>>> - case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
>>> case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
>>> case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
>>> - case RISCV_EXCP_INST_ADDR_MIS:
>>> - case RISCV_EXCP_INST_ACCESS_FAULT:
>>> case RISCV_EXCP_LOAD_ADDR_MIS:
>>> case RISCV_EXCP_STORE_AMO_ADDR_MIS:
>>> case RISCV_EXCP_LOAD_ACCESS_FAULT:
>>> case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
>>> - case RISCV_EXCP_INST_PAGE_FAULT:
>>> case RISCV_EXCP_LOAD_PAGE_FAULT:
>>> case RISCV_EXCP_STORE_PAGE_FAULT:
>>> + write_gva = env->two_stage_lookup;
>>> + tval = env->badaddr;
>>> + if (env->two_stage_indirect_lookup) {
>>> + /*
>>> + * special pseudoinstruction for G-stage fault taken while
>>> + * doing VS-stage page table walk.
>>> + */
>>> + tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
>>> + } else {
>>> + /* transformed instruction for all other load/store faults */
>>> + tinst = riscv_transformed_insn(env, env->bins);
>>> + }
>>> + break;
>>> + case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
>>> + case RISCV_EXCP_INST_ADDR_MIS:
>>> + case RISCV_EXCP_INST_ACCESS_FAULT:
>>> + case RISCV_EXCP_INST_PAGE_FAULT:
>>> write_gva = env->two_stage_lookup;
>>> tval = env->badaddr;
>>> break;
>> Instruction guest-page faults should set [m|h]tinst to one of the
>> pseudoinstructions if env->two_stage_lookup is true. Otherwise it should set
>> [m|h]tinst to zero.
>>
>> In any case, as this seems to be one of the first implementations of
>> [m|h]tinst, it might be worthwhile to confirm with the spec authors and clarify
>> any unclear bits before this gets released.
> This is already handled because tinst is initialized to zero.
If an instruction guest-page fault occurs due to a G-stage fault while doing
VS-stage page table walk, i.e. env->two_stage_indirect_lookup is true (I had
mistakenly wrote env->two_stage_lookup earlier), and the faulting guest
physical address (env->guest_phys_fault_addr) is written to mtval2/htval,
[m|h]tinst must be a pseudoinstruction and not zero. This case is not handled
in the v5 patch.
dramforever
On Fri, Jun 10, 2022 at 5:20 PM dramforever <dramforever@live.com> wrote:
>
> >
> >> In addition, the various V-extension vector load/store instructions do not have
> >> defined transformations, so they should show up in [m|h]tinst as all zeros.
> > Okay, I will update.
> Just a clarification/suggestion: It might be easier to only write non-zero for
> instructions with currently defined transformation. Writing zero is always
> legal, but writing an undefined transformed instruction is not.
> >>> @@ -1355,18 +1558,31 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> >>> if (!async) {
> >>> /* set tval to badaddr for traps with address information */
> >>> switch (cause) {
> >>> - case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> >>> case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
> >>> case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
> >>> - case RISCV_EXCP_INST_ADDR_MIS:
> >>> - case RISCV_EXCP_INST_ACCESS_FAULT:
> >>> case RISCV_EXCP_LOAD_ADDR_MIS:
> >>> case RISCV_EXCP_STORE_AMO_ADDR_MIS:
> >>> case RISCV_EXCP_LOAD_ACCESS_FAULT:
> >>> case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
> >>> - case RISCV_EXCP_INST_PAGE_FAULT:
> >>> case RISCV_EXCP_LOAD_PAGE_FAULT:
> >>> case RISCV_EXCP_STORE_PAGE_FAULT:
> >>> + write_gva = env->two_stage_lookup;
> >>> + tval = env->badaddr;
> >>> + if (env->two_stage_indirect_lookup) {
> >>> + /*
> >>> + * special pseudoinstruction for G-stage fault taken while
> >>> + * doing VS-stage page table walk.
> >>> + */
> >>> + tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
> >>> + } else {
> >>> + /* transformed instruction for all other load/store faults */
> >>> + tinst = riscv_transformed_insn(env, env->bins);
> >>> + }
> >>> + break;
> >>> + case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
> >>> + case RISCV_EXCP_INST_ADDR_MIS:
> >>> + case RISCV_EXCP_INST_ACCESS_FAULT:
> >>> + case RISCV_EXCP_INST_PAGE_FAULT:
> >>> write_gva = env->two_stage_lookup;
> >>> tval = env->badaddr;
> >>> break;
> >> Instruction guest-page faults should set [m|h]tinst to one of the
> >> pseudoinstructions if env->two_stage_lookup is true. Otherwise it should set
> >> [m|h]tinst to zero.
> >>
> >> In any case, as this seems to be one of the first implementations of
> >> [m|h]tinst, it might be worthwhile to confirm with the spec authors and clarify
> >> any unclear bits before this gets released.
> > This is already handled because tinst is initialized to zero.
>
> If an instruction guest-page fault occurs due to a G-stage fault while doing
> VS-stage page table walk, i.e. env->two_stage_indirect_lookup is true (I had
> mistakenly wrote env->two_stage_lookup earlier), and the faulting guest
> physical address (env->guest_phys_fault_addr) is written to mtval2/htval,
> [m|h]tinst must be a pseudoinstruction and not zero. This case is not handled
> in the v5 patch.
The v5 patch is writing pseudoinstruction in [m|h]tinst when
env->two_stage_indirect_lookup is true.
Regards,
Anup
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