Previously, the number of PMP regions was hardcoded to 16 in QEMU.
This patch replaces the fixed value with a new `pmp_regions` field,
allowing platforms to configure the number of PMP regions.
If no specific value is provided, the default number of PMP regions
remains 16 to preserve the existing behavior.
A new CPU parameter num-pmp-regions has been introduced to the QEMU
command line. For example:
-cpu rv64, g=true, c=true, pmp=true, num-pmp-regions=8
Reviewed-by: Frank Chang <frank.ch...@sifive.com>
Signed-off-by: Jay Chang <jay.ch...@sifive.com>
---
target/riscv/cpu.c | 46 ++++++++++++++++++++++++++++++++++++++++++
target/riscv/cpu.h | 2 +-
target/riscv/cpu_cfg.h | 1 +
target/riscv/csr.c | 5 ++++-
target/riscv/machine.c | 3 ++-
target/riscv/pmp.c | 28 ++++++++++++++++---------
6 files changed, 73 insertions(+), 12 deletions(-)
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 09ded6829a..528d77b820 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -512,6 +512,7 @@ static void rv64_sifive_u_cpu_init(Object *obj)
cpu->cfg.ext_zicsr = true;
cpu->cfg.mmu = true;
cpu->cfg.pmp = true;
+ cpu->cfg.pmp_regions = 8;
}
static void rv64_sifive_e_cpu_init(Object *obj)
@@ -529,6 +530,7 @@ static void rv64_sifive_e_cpu_init(Object *obj)
cpu->cfg.ext_zifencei = true;
cpu->cfg.ext_zicsr = true;
cpu->cfg.pmp = true;
+ cpu->cfg.pmp_regions = 8;
}
static void rv64_thead_c906_cpu_init(Object *obj)
@@ -761,6 +763,7 @@ static void rv32_sifive_u_cpu_init(Object *obj)
cpu->cfg.ext_zicsr = true;
cpu->cfg.mmu = true;
cpu->cfg.pmp = true;
+ cpu->cfg.pmp_regions = 8;
}
static void rv32_sifive_e_cpu_init(Object *obj)
@@ -778,6 +781,7 @@ static void rv32_sifive_e_cpu_init(Object *obj)
cpu->cfg.ext_zifencei = true;
cpu->cfg.ext_zicsr = true;
cpu->cfg.pmp = true;
+ cpu->cfg.pmp_regions = 8;
}
static void rv32_ibex_cpu_init(Object *obj)
@@ -1478,6 +1482,7 @@ static void riscv_cpu_init(Object *obj)
cpu->cfg.cbom_blocksize = 64;
cpu->cfg.cbop_blocksize = 64;
cpu->cfg.cboz_blocksize = 64;
+ cpu->cfg.pmp_regions = 16;
cpu->env.vext_ver = VEXT_VERSION_1_00_0;
}
@@ -1935,6 +1940,46 @@ static const PropertyInfo prop_pmp = {
.set = prop_pmp_set,
};
+static void prop_num_pmp_regions_set(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ RISCVCPU *cpu = RISCV_CPU(obj);
+ uint16_t value;
+
+ visit_type_uint16(v, name, &value, errp);
+
+ if (cpu->cfg.pmp_regions != value && riscv_cpu_is_vendor(obj)) {
+ cpu_set_prop_err(cpu, name, errp);
+ return;
+ }
+
+ if (cpu->env.priv_ver < PRIV_VERSION_1_12_0 && value > 16) {
+ error_setg(errp, "Number of PMP regions exceeds maximum available");
+ return;
+ } else if (value > 64) {
+ error_setg(errp, "Number of PMP regions exceeds maximum available");
+ return;
+ }
+
+ cpu_option_add_user_setting(name, value);
+ cpu->cfg.pmp_regions = value;
+}
+
+static void prop_num_pmp_regions_get(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ uint16_t value = RISCV_CPU(obj)->cfg.pmp_regions;
+
+ visit_type_uint16(v, name, &value, errp);
+}
+
+static const PropertyInfo prop_num_pmp_regions = {
+ .type = "uint16",
+ .description = "num-pmp-regions",
+ .get = prop_num_pmp_regions_get,
+ .set = prop_num_pmp_regions_set,
+};
+
static int priv_spec_from_str(const char *priv_spec_str)
{
int priv_version = -1;
@@ -2934,6 +2979,7 @@ static const Property riscv_cpu_properties[] = {
{.name = "mmu", .info = &prop_mmu},
{.name = "pmp", .info = &prop_pmp},
+ {.name = "num-pmp-regions", .info = &prop_num_pmp_regions},
{.name = "priv_spec", .info = &prop_priv_spec},
{.name = "vext_spec", .info = &prop_vext_spec},
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 51e49e03de..50d58c15f2 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -162,7 +162,7 @@ extern RISCVCPUImpliedExtsRule
*riscv_multi_ext_implied_rules[];
#define MMU_USER_IDX 3
-#define MAX_RISCV_PMPS (16)
+#define MAX_RISCV_PMPS (64)
#if !defined(CONFIG_USER_ONLY)
#include "pmp.h"
diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index 8a843482cc..8c805b45f6 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -189,6 +189,7 @@ struct RISCVCPUConfig {
uint16_t cbom_blocksize;
uint16_t cbop_blocksize;
uint16_t cboz_blocksize;
+ uint16_t pmp_regions;
bool mmu;
bool pmp;
bool debug;
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index f8f61ffff5..65f91be9c0 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -736,7 +736,10 @@ static RISCVException dbltrp_hmode(CPURISCVState *env, int
csrno)
static RISCVException pmp(CPURISCVState *env, int csrno)
{
if (riscv_cpu_cfg(env)->pmp) {
- if (csrno <= CSR_PMPCFG3) {
+ uint16_t MAX_PMPCFG = (env->priv_ver >= PRIV_VERSION_1_12_0) ?
++ CSR_PMPCFG15 : CSR_PMPCFG3;
+
+ if (csrno <= MAX_PMPCFG) {
uint32_t reg_index = csrno - CSR_PMPCFG0;
/* TODO: RV128 restriction check */
diff --git a/target/riscv/machine.c b/target/riscv/machine.c
index 889e2b6570..c3e4e78802 100644
--- a/target/riscv/machine.c
+++ b/target/riscv/machine.c
@@ -36,8 +36,9 @@ static int pmp_post_load(void *opaque, int version_id)
RISCVCPU *cpu = opaque;
CPURISCVState *env = &cpu->env;
int i;
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
- for (i = 0; i < MAX_RISCV_PMPS; i++) {
+ for (i = 0; i < pmp_regions; i++) {
pmp_update_rule_addr(env, i);
}
pmp_update_rule_nums(env);
diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c
index c685f7f2c5..3439295d41 100644
--- a/target/riscv/pmp.c
+++ b/target/riscv/pmp.c
@@ -121,7 +121,9 @@ uint32_t pmp_get_num_rules(CPURISCVState *env)
*/
static inline uint8_t pmp_read_cfg(CPURISCVState *env, uint32_t pmp_index)
{
- if (pmp_index < MAX_RISCV_PMPS) {
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
+
+ if (pmp_index < pmp_regions) {
return env->pmp_state.pmp[pmp_index].cfg_reg;
}
@@ -135,7 +137,9 @@ static inline uint8_t pmp_read_cfg(CPURISCVState *env,
uint32_t pmp_index)
*/
static bool pmp_write_cfg(CPURISCVState *env, uint32_t pmp_index, uint8_t val)
{
- if (pmp_index < MAX_RISCV_PMPS) {
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
+
+ if (pmp_index < pmp_regions) {
if (env->pmp_state.pmp[pmp_index].cfg_reg == val) {
/* no change */
return false;
@@ -235,9 +239,10 @@ void pmp_update_rule_addr(CPURISCVState *env, uint32_t
pmp_index)
void pmp_update_rule_nums(CPURISCVState *env)
{
int i;
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
env->pmp_state.num_rules = 0;
- for (i = 0; i < MAX_RISCV_PMPS; i++) {
+ for (i = 0; i < pmp_regions; i++) {
const uint8_t a_field =
pmp_get_a_field(env->pmp_state.pmp[i].cfg_reg);
if (PMP_AMATCH_OFF != a_field) {
@@ -331,6 +336,7 @@ bool pmp_hart_has_privs(CPURISCVState *env, hwaddr addr,
int pmp_size = 0;
hwaddr s = 0;
hwaddr e = 0;
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
/* Short cut if no rules */
if (0 == pmp_get_num_rules(env)) {
@@ -355,7 +361,7 @@ bool pmp_hart_has_privs(CPURISCVState *env, hwaddr addr,
* 1.10 draft priv spec states there is an implicit order
* from low to high
*/
- for (i = 0; i < MAX_RISCV_PMPS; i++) {
+ for (i = 0; i < pmp_regions; i++) {
s = pmp_is_in_range(env, i, addr);
e = pmp_is_in_range(env, i, addr + pmp_size - 1);
@@ -526,8 +532,9 @@ void pmpaddr_csr_write(CPURISCVState *env, uint32_t
addr_index,
{
trace_pmpaddr_csr_write(env->mhartid, addr_index, val);
bool is_next_cfg_tor = false;
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
- if (addr_index < MAX_RISCV_PMPS) {
+ if (addr_index < pmp_regions) {
if (env->pmp_state.pmp[addr_index].addr_reg == val) {
/* no change */
return;
@@ -537,7 +544,7 @@ void pmpaddr_csr_write(CPURISCVState *env, uint32_t
addr_index,
* In TOR mode, need to check the lock bit of the next pmp
* (if there is a next).
*/
- if (addr_index + 1 < MAX_RISCV_PMPS) {
+ if (addr_index + 1 < pmp_regions) {
uint8_t pmp_cfg = env->pmp_state.pmp[addr_index + 1].cfg_reg;
is_next_cfg_tor = PMP_AMATCH_TOR == pmp_get_a_field(pmp_cfg);
@@ -572,8 +579,9 @@ void pmpaddr_csr_write(CPURISCVState *env, uint32_t
addr_index,
target_ulong pmpaddr_csr_read(CPURISCVState *env, uint32_t addr_index)
{
target_ulong val = 0;
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
- if (addr_index < MAX_RISCV_PMPS) {
+ if (addr_index < pmp_regions) {
val = env->pmp_state.pmp[addr_index].addr_reg;
trace_pmpaddr_csr_read(env->mhartid, addr_index, val);
} else {
@@ -591,6 +599,7 @@ void mseccfg_csr_write(CPURISCVState *env, target_ulong val)
{
int i;
uint64_t mask = MSECCFG_MMWP | MSECCFG_MML;
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
/* Update PMM field only if the value is valid according to Zjpm v1.0 */
if (riscv_cpu_cfg(env)->ext_smmpm &&
riscv_cpu_mxl(env) == MXL_RV64 &&
@@ -602,7 +611,7 @@ void mseccfg_csr_write(CPURISCVState *env, target_ulong val)
/* RLB cannot be enabled if it's already 0 and if any regions are locked */
if (!MSECCFG_RLB_ISSET(env)) {
- for (i = 0; i < MAX_RISCV_PMPS; i++) {
+ for (i = 0; i < pmp_regions; i++) {
if (pmp_is_locked(env, i)) {
val &= ~MSECCFG_RLB;
break;
@@ -658,6 +667,7 @@ target_ulong pmp_get_tlb_size(CPURISCVState *env, hwaddr
addr)
hwaddr tlb_sa = addr & ~(TARGET_PAGE_SIZE - 1);
hwaddr tlb_ea = tlb_sa + TARGET_PAGE_SIZE - 1;
int i;
+ uint16_t pmp_regions = riscv_cpu_cfg(env)->pmp_regions;
/*
* If PMP is not supported or there are no PMP rules, the TLB page will not
@@ -668,7 +678,7 @@ target_ulong pmp_get_tlb_size(CPURISCVState *env, hwaddr
addr)
return TARGET_PAGE_SIZE;
}
- for (i = 0; i < MAX_RISCV_PMPS; i++) {
+ for (i = 0; i < pmp_regions; i++) {
if (pmp_get_a_field(env->pmp_state.pmp[i].cfg_reg) == PMP_AMATCH_OFF) {
continue;
}
--
2.48.1
