diff mbox series

[v6,04/12] target/riscv: pmu: Make number of counters configurable

Message ID 20220303235440.638790-5-atishp@rivosinc.com (mailing list archive)
State New, archived
Headers show
Series Improve PMU support | expand

Commit Message

Atish Kumar Patra March 3, 2022, 11:54 p.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 3b781ef455ff..2d2b0b04fbc8 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -779,7 +779,7 @@  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 9bece5056c63..299dccf286e0 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;
@@ -383,6 +382,7 @@  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 88ae827ba174..75f18a6323c2 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -64,15 +64,45 @@  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;
     }
 
@@ -100,7 +130,7 @@  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)) {
@@ -155,7 +185,7 @@  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) &&
@@ -3509,35 +3539,35 @@  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 },