target/riscv: Don't assume PMU counters are continuous

Check the PMU available bitmask when checking if a counter is valid
rather than comparing the index against the number of PMUs.

Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20231031154000.18134-3-rbradford@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index fc26b52c8876e92b2e404208898e97e38ca89ec3..fde7ce1a5336b5d744c6676edadfe64b1688a2df 100644 (file)
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -188,7 +188,8 @@ static RISCVException zcmt(CPURISCVState *env, int csrno)
 #if !defined(CONFIG_USER_ONLY)
 static RISCVException mctr(CPURISCVState *env, int csrno)
 {
-    int pmu_num = riscv_cpu_cfg(env)->pmu_num;
+    RISCVCPU *cpu = env_archcpu(env);
+    uint32_t pmu_avail_ctrs = cpu->pmu_avail_ctrs;
     int ctr_index;
     int base_csrno = CSR_MHPMCOUNTER3;
 
@@ -197,7 +198,7 @@ static RISCVException mctr(CPURISCVState *env, int csrno)
         base_csrno += 0x80;
     }
     ctr_index = csrno - base_csrno;
-    if (!pmu_num || ctr_index >= pmu_num) {
+    if ((BIT(ctr_index) & pmu_avail_ctrs >> 3) == 0) {
         /* The PMU is not enabled or counter is out of range */
         return RISCV_EXCP_ILLEGAL_INST;
     }