This patch adds PMU support, We just sets some cpucfg6 default value
to PMU config on kvm mode, and then check the PMU config with kvm ioctl
KVM_GET_DEVICE_ATTR.
e.g
'... -cpu max,pmu=on,pmnum=[1-16]';
'... -cpu max,pmu=on' (default pmnum = 4);
'... -cpu max,pmu=off' (disable PMU)
Signed-off-by: Song Gao <gaos...@loongson.cn>
---
This patch adds the 'RFC' heading because it requires
the kernel to merge into patch[1] first
[1]: https://lore.kernel.org/all/20240507120140.3119714-1-gaos...@loongson.cn/
target/loongarch/cpu.h | 2 +
target/loongarch/cpu.c | 64 +++++++++++++++++++++++++++
target/loongarch/kvm/kvm.c | 55 ++++++++++++++++++++++-
target/loongarch/loongarch-qmp-cmds.c | 2 +-
4 files changed, 121 insertions(+), 2 deletions(-)
diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
index 6c41fafb70..d834649106 100644
--- a/target/loongarch/cpu.h
+++ b/target/loongarch/cpu.h
@@ -184,6 +184,8 @@ FIELD(CPUCFG6, PMNUM, 4, 4)
FIELD(CPUCFG6, PMBITS, 8, 6)
FIELD(CPUCFG6, UPM, 14, 1)
+#define PMNUM_MAX 16
+
/* cpucfg[16] bits */
FIELD(CPUCFG16, L1_IUPRE, 0, 1)
FIELD(CPUCFG16, L1_IUUNIFY, 1, 1)
diff --git a/target/loongarch/cpu.c b/target/loongarch/cpu.c
index a0cad53676..c78ee3f0b1 100644
--- a/target/loongarch/cpu.c
+++ b/target/loongarch/cpu.c
@@ -8,6 +8,7 @@
#include "qemu/osdep.h"
#include "qemu/log.h"
#include "qemu/qemu-print.h"
+#include "qemu/error-report.h"
#include "qapi/error.h"
#include "qemu/module.h"
#include "sysemu/qtest.h"
@@ -19,6 +20,7 @@
#include "internals.h"
#include "fpu/softfloat-helpers.h"
#include "cpu-csr.h"
+#include "qapi/visitor.h"
#ifndef CONFIG_USER_ONLY
#include "sysemu/reset.h"
#endif
@@ -421,6 +423,14 @@ static void loongarch_la464_initfn(Object *obj)
data = FIELD_DP32(data, CPUCFG5, CC_DIV, 1);
env->cpucfg[5] = data;
+ if (kvm_enabled()) {
+ data = 0;
+ data = FIELD_DP32(data, CPUCFG6, PMP, 1);
+ data = FIELD_DP32(data, CPUCFG6, PMNUM, 3);
+ data = FIELD_DP32(data, CPUCFG6, PMBITS, 63);
+ env->cpucfg[6] = data;
+ }
+
data = 0;
data = FIELD_DP32(data, CPUCFG16, L1_IUPRE, 1);
data = FIELD_DP32(data, CPUCFG16, L1_DPRE, 1);
@@ -643,6 +653,48 @@ static void loongarch_set_lasx(Object *obj, bool value,
Error **errp)
}
}
+static bool loongarch_get_pmu(Object *obj, Error **errp)
+{
+ LoongArchCPU *cpu = LOONGARCH_CPU(obj);
+
+ return !!(FIELD_EX32(cpu->env.cpucfg[6], CPUCFG6, PMP));
+}
+
+static void loongarch_set_pmu(Object *obj, bool value, Error **errp)
+{
+ LoongArchCPU *cpu = LOONGARCH_CPU(obj);
+
+ cpu->env.cpucfg[6] = FIELD_DP32(cpu->env.cpucfg[6], CPUCFG6, PMP, value);
+}
+
+static void loongarch_get_pmnum(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ LoongArchCPU *cpu = LOONGARCH_CPU(obj);
+ uint32_t value = FIELD_EX32(cpu->env.cpucfg[6], CPUCFG6, PMNUM);
+
+ visit_type_uint32(v, name, &value, errp);
+}
+
+static void loongarch_set_pmnum(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ LoongArchCPU *cpu = LOONGARCH_CPU(obj);
+ uint32_t *value= opaque;
+
+ if (!visit_type_uint32(v, name, value, errp)) {
+ return;
+ }
+ if ((*value <= PMNUM_MAX) && (*value > 0)) {
+ cpu->env.cpucfg[6] = FIELD_DP32(cpu->env.cpucfg[6], CPUCFG6, PMNUM,
*value -1);
+ } else {
+ error_report("Performance counter number need be in [1- %d]\n",
PMNUM_MAX);
+ exit(EXIT_FAILURE);
+ }
+}
+
void loongarch_cpu_post_init(Object *obj)
{
LoongArchCPU *cpu = LOONGARCH_CPU(obj);
@@ -655,6 +707,18 @@ void loongarch_cpu_post_init(Object *obj)
object_property_add_bool(obj, "lasx", loongarch_get_lasx,
loongarch_set_lasx);
}
+
+ if (kvm_enabled()) {
+ object_property_add_bool(obj, "pmu", loongarch_get_pmu,
+ loongarch_set_pmu);
+ if (FIELD_EX32(cpu->env.cpucfg[6], CPUCFG6, PMP)) {
+ uint32_t value = 4;
+ object_property_add(obj, "pmnum", "uint32",
+ loongarch_get_pmnum,
+ loongarch_set_pmnum, NULL,
+ (void *)&value);
+ }
+ }
}
static void loongarch_cpu_init(Object *obj)
diff --git a/target/loongarch/kvm/kvm.c b/target/loongarch/kvm/kvm.c
index bc75552d0f..a9f9020071 100644
--- a/target/loongarch/kvm/kvm.c
+++ b/target/loongarch/kvm/kvm.c
@@ -556,6 +556,53 @@ static int kvm_check_cpucfg2(CPUState *cs)
return ret;
}
+static int kvm_check_cpucfg6(CPUState *cs)
+{
+ int ret;
+ uint64_t val;
+ struct kvm_device_attr attr = {
+ .group = KVM_LOONGARCH_VCPU_CPUCFG,
+ .attr = 6,
+ .addr = (uint64_t)&val,
+ };
+ LoongArchCPU *cpu = LOONGARCH_CPU(cs);
+ CPULoongArchState *env = &cpu->env;
+
+ ret = kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, &attr);
+ if (!ret) {
+ kvm_vcpu_ioctl(cs, KVM_GET_DEVICE_ATTR, &attr);
+
+ if (FIELD_EX32(env->cpucfg[6], CPUCFG6, PMP)) {
+ /* Check PMP */
+ if (!FIELD_EX32(val, CPUCFG6, PMP)) {
+ error_report("'pmu' feature not supported by KVM on this host"
+ " Please disable 'pmu' with "
+ "'... -cpu XXX,pmu=off ...'\n");
+ exit(EXIT_FAILURE);
+ }
+ /* Check PMNUM */
+ int guest_pmnum = FIELD_EX32(env->cpucfg[6], CPUCFG6, PMNUM);
+ int host_pmnum = FIELD_EX32(val, CPUCFG6, PMNUM);
+ if (guest_pmnum > host_pmnum){
+ warn_report("The guest pmnum %d larger than KVM support %d\n",
+ guest_pmnum, host_pmnum);
+ env->cpucfg[6] = FIELD_DP32(env->cpucfg[6], CPUCFG6,
+ PMNUM, host_pmnum);
+ }
+ /* Check PMBITS */
+ int guest_pmbits = FIELD_EX32(env->cpucfg[6], CPUCFG6, PMBITS);
+ int host_pmbits = FIELD_EX32(val, CPUCFG6, PMBITS);
+ if (guest_pmbits != host_pmbits) {
+ warn_report("The host not support PMBITS %d\n", guest_pmbits);
+ env->cpucfg[6] = FIELD_DP32(env->cpucfg[6], CPUCFG6,
+ PMBITS, host_pmbits);
+ }
+ }
+ }
+
+ return ret;
+}
+
static int kvm_loongarch_put_cpucfg(CPUState *cs)
{
int i, ret = 0;
@@ -568,7 +615,13 @@ static int kvm_loongarch_put_cpucfg(CPUState *cs)
if (ret) {
return ret;
}
- }
+ }
+ if (i == 6) {
+ ret = kvm_check_cpucfg6(cs);
+ if (ret) {
+ return ret;
+ }
+ }
val = env->cpucfg[i];
ret = kvm_set_one_reg(cs, KVM_IOC_CPUCFG(i), &val);
if (ret < 0) {
diff --git a/target/loongarch/loongarch-qmp-cmds.c
b/target/loongarch/loongarch-qmp-cmds.c
index 8721a5eb13..d7f2af363b 100644
--- a/target/loongarch/loongarch-qmp-cmds.c
+++ b/target/loongarch/loongarch-qmp-cmds.c
@@ -40,7 +40,7 @@ CpuDefinitionInfoList *qmp_query_cpu_definitions(Error **errp)
}
static const char *cpu_model_advertised_features[] = {
- "lsx", "lasx", NULL
+ "lsx", "lasx", "pmu", "pmnum", NULL
};
CpuModelExpansionInfo *qmp_query_cpu_model_expansion(CpuModelExpansionType
type,
--
2.25.1
