The RISC-V privileged specification v1.12 defines few execution
environment configuration CSRs that can be used enable/disable
extensions per privilege levels.
Add the basic support for these CSRs.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
---
target/riscv/cpu.h | 6 +++
target/riscv/cpu_bits.h | 39 ++++++++++++++++++
target/riscv/csr.c | 87 +++++++++++++++++++++++++++++++++++++++++
target/riscv/machine.c | 24 ++++++++++++
4 files changed, 156 insertions(+)
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 0741f9822cf0..675f8716b239 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -303,6 +303,12 @@ struct CPURISCVState {
target_ulong spmbase;
target_ulong upmmask;
target_ulong upmbase;
+
+ /* CSRs for execution enviornment configuration */
+
+ uint64_t menvcfg;
+ target_ulong senvcfg;
+ uint64_t henvcfg;
#endif
float_status fp_status;
diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
index 89440241632a..58a0a8d69f72 100644
--- a/target/riscv/cpu_bits.h
+++ b/target/riscv/cpu_bits.h
@@ -202,6 +202,9 @@
#define CSR_STVEC 0x105
#define CSR_SCOUNTEREN 0x106
+/* Supervisor Configuration CSRs */
+#define CSR_SENVCFG 0x10A
+
/* Supervisor Trap Handling */
#define CSR_SSCRATCH 0x140
#define CSR_SEPC 0x141
@@ -247,6 +250,10 @@
#define CSR_HTIMEDELTA 0x605
#define CSR_HTIMEDELTAH 0x615
+/* Hypervisor Configuration CSRs */
+#define CSR_HENVCFG 0x60A
+#define CSR_HENVCFGH 0x61A
+
/* Virtual CSRs */
#define CSR_VSSTATUS 0x200
#define CSR_VSIE 0x204
@@ -290,6 +297,10 @@
#define CSR_VSIEH 0x214
#define CSR_VSIPH 0x254
+/* Machine Configuration CSRs */
+#define CSR_MENVCFG 0x30A
+#define CSR_MENVCFGH 0x31A
+
/* Enhanced Physical Memory Protection (ePMP) */
#define CSR_MSECCFG 0x747
#define CSR_MSECCFGH 0x757
@@ -654,6 +665,34 @@ typedef enum RISCVException {
#define PM_EXT_CLEAN 0x00000002ULL
#define PM_EXT_DIRTY 0x00000003ULL
+/* Execution enviornment configuration bits */
+#define MENVCFG_FIOM BIT(0)
+#define MENVCFG_CBIE (3UL << 4)
+#define MENVCFG_CBCFE BIT(6)
+#define MENVCFG_CBZE BIT(7)
+#define MENVCFG_PBMTE BIT(62)
+#define MENVCFG_STCE BIT(63)
+
+/* For RV32 */
+#define MENVCFGH_PBMTE BIT(30)
+#define MENVCFGH_STCE BIT(31)
+
+#define SENVCFG_FIOM MENVCFG_FIOM
+#define SENVCFG_CBIE MENVCFG_CBIE
+#define SENVCFG_CBCFE MENVCFG_CBCFE
+#define SENVCFG_CBZE MENVCFG_CBZE
+
+#define HENVCFG_FIOM MENVCFG_FIOM
+#define HENVCFG_CBIE MENVCFG_CBIE
+#define HENVCFG_CBCFE MENVCFG_CBCFE
+#define HENVCFG_CBZE MENVCFG_CBZE
+#define HENVCFG_PBMTE MENVCFG_PBMTE
+#define HENVCFG_STCE MENVCFG_STCE
+
+/* For RV32 */
+#define HENVCFGH_PBMTE MENVCFGH_PBMTE
+#define HENVCFGH_STCE MENVCFGH_STCE
+
/* Offsets for every pair of control bits per each priv level */
#define XS_OFFSET 0ULL
#define U_OFFSET 2ULL
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 4366e5e95ce8..88c839a5ffaa 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -1366,6 +1366,81 @@ static RISCVException write_mtval(CPURISCVState *env,
int csrno,
return RISCV_EXCP_NONE;
}
+/* Execution environment configuration setup */
+static RISCVException read_menvcfg(CPURISCVState *env, int csrno,
+ target_ulong *val)
+{
+ *val = env->menvcfg;
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_menvcfg(CPURISCVState *env, int csrno,
+ target_ulong val)
+{
+ env->menvcfg = val;
+ return RISCV_EXCP_NONE;
+}
+
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
+ target_ulong *val)
+{
+ *val = env->senvcfg;
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_senvcfg(CPURISCVState *env, int csrno,
+ target_ulong val)
+{
+ env->senvcfg = val;
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
+ target_ulong *val)
+{
+ *val = env->henvcfg;
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
+ target_ulong val)
+{
+ env->henvcfg = val;
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
+ target_ulong *val)
+{
+ *val = env->henvcfg >> 32;
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
+ target_ulong val)
+{
+ uint64_t valh = (uint64_t)val << 32;
+ env->henvcfg |= valh;
+
+ return RISCV_EXCP_NONE;
+}
+
static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
uint64_t *ret_val,
uint64_t new_val, uint64_t wr_mask)
@@ -3069,6 +3144,18 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
[CSR_MVIPH] = { "mviph", aia_any32, read_zero, write_ignore },
[CSR_MIPH] = { "miph", aia_any32, NULL, NULL, rmw_miph },
+ /* Execution environment configuration */
+ [CSR_MENVCFG] = { "menvcfg", any, read_menvcfg, write_menvcfg,
+ .min_priv_ver = PRIV_VERSION_1_12_0
},
+ [CSR_MENVCFGH] = { "menvcfgh", any32, read_menvcfgh, write_menvcfgh,
+ .min_priv_ver = PRIV_VERSION_1_12_0
},
+ [CSR_SENVCFG] = { "senvcfg", smode, read_senvcfg, write_senvcfg,
+ .min_priv_ver = PRIV_VERSION_1_12_0
},
+ [CSR_HENVCFG] = { "henvcfg", hmode, read_henvcfg, write_henvcfg,
+ .min_priv_ver = PRIV_VERSION_1_12_0
},
+ [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh, write_henvcfgh,
+ .min_priv_ver = PRIV_VERSION_1_12_0
},
+
/* Supervisor Trap Setup */
[CSR_SSTATUS] = { "sstatus", smode, read_sstatus, write_sstatus,
NULL,
read_sstatus_i128
},
diff --git a/target/riscv/machine.c b/target/riscv/machine.c
index 9895930b2976..4a50a05937fa 100644
--- a/target/riscv/machine.c
+++ b/target/riscv/machine.c
@@ -220,6 +220,29 @@ static const VMStateDescription vmstate_kvmtimer = {
}
};
+/* TODO: henvcfg need both hyper_needed & envcfg_needed */
+static bool envcfg_needed(void *opaque)
+{
+ RISCVCPU *cpu = opaque;
+ CPURISCVState *env = &cpu->env;
+
+ return (env->priv_ver >= PRIV_VERSION_1_12_0 ? 1 : 0);
+}
+
+static const VMStateDescription vmstate_envcfg = {
+ .name = "cpu/envcfg",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .needed = envcfg_needed,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT64(env.menvcfg, RISCVCPU),
+ VMSTATE_UINTTL(env.senvcfg, RISCVCPU),
+ VMSTATE_UINT64(env.henvcfg, RISCVCPU),
+
+ VMSTATE_END_OF_LIST()
+ }
+};
+
const VMStateDescription vmstate_riscv_cpu = {
.name = "cpu",
.version_id = 3,
@@ -280,6 +303,7 @@ const VMStateDescription vmstate_riscv_cpu = {
&vmstate_pointermasking,
&vmstate_rv128,
&vmstate_kvmtimer,
+ &vmstate_envcfg,
NULL
}
};