commit a5a92fd6ef038170231933c60cc2780f52b3a2e1
author Atish Patra <atish.patra@wdc.com> Mon Jun 20 16:15:52 2022 -0700
committer Alistair Francis <alistair@alistair23.me> Sun Jul 03 10:03:20 2022 +1000
tree 9bc5c4429818ee21e9f8cbe4954f6d5b1a0b04e0
parent 562009e47c622298f82ee7557be9e15d5e50cee5

target/riscv: Implement PMU CSR predicate function for S-mode

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>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-Id: <20220620231603.2547260-3-atishp@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/csr.c

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 46bd417..58d07c5 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -79,6 +79,57 @@
         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_mxl(env) == MXL_RV32) {
+            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: