diff mbox series

[v5,04/12] target/riscv: pmu: Make number of counters configurable

Message ID 20220219002518.1936806-5-atishp@rivosinc.com (mailing list archive)
State New, archived
Headers show
Series Improve PMU support | expand

Commit Message

Atish Kumar Patra Feb. 19, 2022, 12:25 a.m. UTC 
The RISC-V privilege specification provides flexibility to implement
any number of counters from 29 programmable counters. However, the QEMU
implements all the counters.

Make it configurable through pmu config parameter which now will indicate
how many programmable counters should be implemented by the cpu.

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
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/cpu.c |  2 +-
 target/riscv/cpu.h |  2 +-
 target/riscv/csr.c | 96 ++++++++++++++++++++++++++++++----------------
 3 files changed, 65 insertions(+), 35 deletions(-)
diff mbox series

Patch

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 173b9d3c5d3e..02e089710a7e 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -768,7 +768,7 @@  static Property riscv_cpu_properties[] = {
     DEFINE_PROP_BOOL("u", RISCVCPU, cfg.ext_u, true),
     DEFINE_PROP_BOOL("v", RISCVCPU, cfg.ext_v, false),
     DEFINE_PROP_BOOL("h", RISCVCPU, cfg.ext_h, true),
-    DEFINE_PROP_BOOL("pmu", RISCVCPU, cfg.ext_pmu, true),
+    DEFINE_PROP_UINT8("pmu-num", RISCVCPU, cfg.pmu_num, 16),
     DEFINE_PROP_BOOL("Zifencei", RISCVCPU, cfg.ext_ifencei, true),
     DEFINE_PROP_BOOL("Zicsr", RISCVCPU, cfg.ext_icsr, true),
     DEFINE_PROP_BOOL("Zfh", RISCVCPU, cfg.ext_zfh, false),
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 2dc491887f24..f6b994a74ed9 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -365,7 +365,6 @@  struct RISCVCPUConfig {
     bool ext_zbb;
     bool ext_zbc;
     bool ext_zbs;
-    bool ext_pmu;
     bool ext_ifencei;
     bool ext_icsr;
     bool ext_svinval;
@@ -379,6 +378,7 @@  struct RISCVCPUConfig {
     /* Vendor-specific custom extensions */
     bool ext_XVentanaCondOps;
 
+    uint8_t pmu_num;
     char *priv_spec;
     char *user_spec;
     char *bext_spec;
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 2c3bba81c8af..d69bd2d88454 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -62,15 +62,45 @@  static RISCVException vs(CPURISCVState *env, int csrno)
     return RISCV_EXCP_ILLEGAL_INST;
 }
 
+static RISCVException mctr(CPURISCVState *env, int csrno)
+{
+#if !defined(CONFIG_USER_ONLY)
+    CPUState *cs = env_cpu(env);
+    RISCVCPU *cpu = RISCV_CPU(cs);
+    int ctr_index;
+    int base_csrno = CSR_MHPMCOUNTER3;
+
+    if ((riscv_cpu_mxl(env) == MXL_RV32) && csrno >= CSR_MCYCLEH) {
+        /* Offset for RV32 mhpmcounternh counters */
+        base_csrno += 0x80;
+    }
+    ctr_index = csrno - base_csrno;
+    if (!cpu->cfg.pmu_num || ctr_index >= cpu->cfg.pmu_num) {
+        /* The PMU is not enabled or counter is out of range*/
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+#endif
+    return RISCV_EXCP_NONE;
+}
+
 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;
+    int base_csrno = CSR_HPMCOUNTER3;
+    bool rv32 = riscv_cpu_mxl(env) == MXL_RV32 ? true : false;
+
+    if (rv32 && csrno >= CSR_CYCLEH) {
+        /* Offset for RV32 hpmcounternh counters */
+        base_csrno += 0x80;
+    }
+    ctr_index = csrno - base_csrno;
 
-    if (!cpu->cfg.ext_pmu) {
-        /* The PMU extension is not enabled */
+    if (!cpu->cfg.pmu_num || ctr_index >= (cpu->cfg.pmu_num)) {
+        /* No counter is enabled in PMU or the counter is out of range */
         return RISCV_EXCP_ILLEGAL_INST;
     }
 
@@ -98,7 +128,7 @@  static RISCVException ctr(CPURISCVState *env, int csrno)
             }
             break;
         }
-        if (riscv_cpu_is_32bit(env)) {
+        if (rv32) {
             switch (csrno) {
             case CSR_CYCLEH:
                 if (!get_field(env->mcounteren, COUNTEREN_CY)) {
@@ -153,7 +183,7 @@  static RISCVException ctr(CPURISCVState *env, int csrno)
             }
             break;
         }
-        if (riscv_cpu_mxl(env) == MXL_RV32) {
+        if (rv32) {
             switch (csrno) {
             case CSR_CYCLEH:
                 if (!get_field(env->hcounteren, COUNTEREN_CY) &&
@@ -3493,35 +3523,35 @@  riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
     [CSR_HPMCOUNTER30]   = { "hpmcounter30",   ctr,    read_zero },
     [CSR_HPMCOUNTER31]   = { "hpmcounter31",   ctr,    read_zero },
 
-    [CSR_MHPMCOUNTER3]   = { "mhpmcounter3",   any,    read_zero },
-    [CSR_MHPMCOUNTER4]   = { "mhpmcounter4",   any,    read_zero },
-    [CSR_MHPMCOUNTER5]   = { "mhpmcounter5",   any,    read_zero },
-    [CSR_MHPMCOUNTER6]   = { "mhpmcounter6",   any,    read_zero },
-    [CSR_MHPMCOUNTER7]   = { "mhpmcounter7",   any,    read_zero },
-    [CSR_MHPMCOUNTER8]   = { "mhpmcounter8",   any,    read_zero },
-    [CSR_MHPMCOUNTER9]   = { "mhpmcounter9",   any,    read_zero },
-    [CSR_MHPMCOUNTER10]  = { "mhpmcounter10",  any,    read_zero },
-    [CSR_MHPMCOUNTER11]  = { "mhpmcounter11",  any,    read_zero },
-    [CSR_MHPMCOUNTER12]  = { "mhpmcounter12",  any,    read_zero },
-    [CSR_MHPMCOUNTER13]  = { "mhpmcounter13",  any,    read_zero },
-    [CSR_MHPMCOUNTER14]  = { "mhpmcounter14",  any,    read_zero },
-    [CSR_MHPMCOUNTER15]  = { "mhpmcounter15",  any,    read_zero },
-    [CSR_MHPMCOUNTER16]  = { "mhpmcounter16",  any,    read_zero },
-    [CSR_MHPMCOUNTER17]  = { "mhpmcounter17",  any,    read_zero },
-    [CSR_MHPMCOUNTER18]  = { "mhpmcounter18",  any,    read_zero },
-    [CSR_MHPMCOUNTER19]  = { "mhpmcounter19",  any,    read_zero },
-    [CSR_MHPMCOUNTER20]  = { "mhpmcounter20",  any,    read_zero },
-    [CSR_MHPMCOUNTER21]  = { "mhpmcounter21",  any,    read_zero },
-    [CSR_MHPMCOUNTER22]  = { "mhpmcounter22",  any,    read_zero },
-    [CSR_MHPMCOUNTER23]  = { "mhpmcounter23",  any,    read_zero },
-    [CSR_MHPMCOUNTER24]  = { "mhpmcounter24",  any,    read_zero },
-    [CSR_MHPMCOUNTER25]  = { "mhpmcounter25",  any,    read_zero },
-    [CSR_MHPMCOUNTER26]  = { "mhpmcounter26",  any,    read_zero },
-    [CSR_MHPMCOUNTER27]  = { "mhpmcounter27",  any,    read_zero },
-    [CSR_MHPMCOUNTER28]  = { "mhpmcounter28",  any,    read_zero },
-    [CSR_MHPMCOUNTER29]  = { "mhpmcounter29",  any,    read_zero },
-    [CSR_MHPMCOUNTER30]  = { "mhpmcounter30",  any,    read_zero },
-    [CSR_MHPMCOUNTER31]  = { "mhpmcounter31",  any,    read_zero },
+    [CSR_MHPMCOUNTER3]   = { "mhpmcounter3",   mctr,   read_zero },
+    [CSR_MHPMCOUNTER4]   = { "mhpmcounter4",   mctr,   read_zero },
+    [CSR_MHPMCOUNTER5]   = { "mhpmcounter5",   mctr,   read_zero },
+    [CSR_MHPMCOUNTER6]   = { "mhpmcounter6",   mctr,   read_zero },
+    [CSR_MHPMCOUNTER7]   = { "mhpmcounter7",   mctr,   read_zero },
+    [CSR_MHPMCOUNTER8]   = { "mhpmcounter8",   mctr,   read_zero },
+    [CSR_MHPMCOUNTER9]   = { "mhpmcounter9",   mctr,   read_zero },
+    [CSR_MHPMCOUNTER10]  = { "mhpmcounter10",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER11]  = { "mhpmcounter11",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER12]  = { "mhpmcounter12",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER13]  = { "mhpmcounter13",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER14]  = { "mhpmcounter14",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER15]  = { "mhpmcounter15",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER16]  = { "mhpmcounter16",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER17]  = { "mhpmcounter17",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER18]  = { "mhpmcounter18",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER19]  = { "mhpmcounter19",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER20]  = { "mhpmcounter20",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER21]  = { "mhpmcounter21",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER22]  = { "mhpmcounter22",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER23]  = { "mhpmcounter23",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER24]  = { "mhpmcounter24",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER25]  = { "mhpmcounter25",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER26]  = { "mhpmcounter26",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER27]  = { "mhpmcounter27",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER28]  = { "mhpmcounter28",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER29]  = { "mhpmcounter29",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER30]  = { "mhpmcounter30",  mctr,   read_zero },
+    [CSR_MHPMCOUNTER31]  = { "mhpmcounter31",  mctr,   read_zero },
 
     [CSR_MHPMEVENT3]     = { "mhpmevent3",     any,    read_zero },
     [CSR_MHPMEVENT4]     = { "mhpmevent4",     any,    read_zero },