[PATCH v4 02/11] target/riscv: Implement PMU CSR predicate function for S-mode

[Atish Patra]

From: Atish Patra <atish.patra@wdc.com>

Currently, the predicate function for PMU related CSRs only works if
virtualization is enabled. It also does not check mcounteren bits before
before cycle/minstret/hpmcounterx access.

Support supervisor mode access in the predicate function as well.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
---
 target/riscv/csr.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 53a621fdbaef..823cc306d74b 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -63,12 +63,64 @@ static RISCVException ctr(CPURISCVState *env, int csrno)
 #if !defined(CONFIG_USER_ONLY)
     CPUState *cs = env_cpu(env);
     RISCVCPU *cpu = RISCV_CPU(cs);
+    int ctr_index;
 
     if (!cpu->cfg.ext_counters) {
         /* The Counters extensions is not enabled */
         return RISCV_EXCP_ILLEGAL_INST;
     }
 
+    if (env->priv == PRV_S) {
+        switch (csrno) {
+        case CSR_CYCLE:
+            if (!get_field(env->mcounteren, COUNTEREN_CY)) {
+                return RISCV_EXCP_ILLEGAL_INST;
+            }
+            break;
+        case CSR_TIME:
+            if (!get_field(env->mcounteren, COUNTEREN_TM)) {
+                return RISCV_EXCP_ILLEGAL_INST;
+            }
+            break;
+        case CSR_INSTRET:
+            if (!get_field(env->mcounteren, COUNTEREN_IR)) {
+                return RISCV_EXCP_ILLEGAL_INST;
+            }
+            break;
+        case CSR_HPMCOUNTER3...CSR_HPMCOUNTER31:
+            ctr_index = csrno - CSR_CYCLE;
+            if (!get_field(env->mcounteren, 1 << ctr_index)) {
+                return RISCV_EXCP_ILLEGAL_INST;
+            }
+            break;
+        }
+        if (riscv_cpu_is_32bit(env)) {
+            switch (csrno) {
+            case CSR_CYCLEH:
+                if (!get_field(env->mcounteren, COUNTEREN_CY)) {
+                    return RISCV_EXCP_ILLEGAL_INST;
+                }
+                break;
+            case CSR_TIMEH:
+                if (!get_field(env->mcounteren, COUNTEREN_TM)) {
+                    return RISCV_EXCP_ILLEGAL_INST;
+                }
+                break;
+            case CSR_INSTRETH:
+                if (!get_field(env->mcounteren, COUNTEREN_IR)) {
+                    return RISCV_EXCP_ILLEGAL_INST;
+                }
+                break;
+            case CSR_HPMCOUNTER3H...CSR_HPMCOUNTER31H:
+                ctr_index = csrno - CSR_CYCLEH;
+                if (!get_field(env->mcounteren, 1 << ctr_index)) {
+                    return RISCV_EXCP_ILLEGAL_INST;
+                }
+                break;
+            }
+        }
+    }
+
     if (riscv_cpu_virt_enabled(env)) {
         switch (csrno) {
         case CSR_CYCLE:
-- 
2.30.2