[PATCH v2 18/18, KVMTOOL] kvm: add a vcpu feature for SPEv1 support

Andrew Murray
2019-12-20T14:31:31Z

This is a runtime configurable for KVM tool to enable Statistical
Profiling Extensions version 1 support in guest kernel. A command line
option --spe is required to use the same.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
[ Add SPE to init features ]
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
---
Makefile | 2 +-
arm/aarch64/arm-cpu.c | 2 +
arm/aarch64/include/kvm/kvm-config-arch.h | 2 +
arm/aarch64/include/kvm/kvm-cpu-arch.h | 3 +-
arm/aarch64/kvm-cpu.c | 4 ++
arm/include/arm-common/kvm-config-arch.h | 1 +
arm/include/arm-common/spe.h | 4 ++
arm/spe.c | 81 +++++++++++++++++++++++
8 files changed, 97 insertions(+), 2 deletions(-)
create mode 100644 arm/include/arm-common/spe.h
create mode 100644 arm/spe.c

diff --git a/Makefile b/Makefile
index 3862112c5ec6..04dddb3e7699 100644
--- a/Makefile
+++ b/Makefile
@@ -158,7 +158,7 @@ endif
# ARM
OBJS_ARM_COMMON := arm/fdt.o arm/gic.o arm/gicv2m.o arm/ioport.o \
arm/kvm.o arm/kvm-cpu.o arm/pci.o arm/timer.o \
- arm/pmu.o
+ arm/pmu.o arm/spe.o
HDRS_ARM_COMMON := arm/include
ifeq ($(ARCH), arm)
DEFINES += -DCONFIG_ARM
diff --git a/arm/aarch64/arm-cpu.c b/arm/aarch64/arm-cpu.c
index d7572b7790b1..6ccea033f361 100644
--- a/arm/aarch64/arm-cpu.c
+++ b/arm/aarch64/arm-cpu.c
@@ -6,6 +6,7 @@
#include "arm-common/gic.h"
#include "arm-common/timer.h"
#include "arm-common/pmu.h"
+#include "arm-common/spe.h"

#include <linux/byteorder.h>
#include <linux/types.h>
@@ -17,6 +18,7 @@ static void generate_fdt_nodes(void *fdt, struct kvm *kvm)
gic__generate_fdt_nodes(fdt, kvm->cfg.arch.irqchip);
timer__generate_fdt_nodes(fdt, kvm, timer_interrupts);
pmu__generate_fdt_nodes(fdt, kvm);
+ spe__generate_fdt_nodes(fdt, kvm);
}

static int arm_cpu__vcpu_init(struct kvm_cpu *vcpu)
diff --git a/arm/aarch64/include/kvm/kvm-config-arch.h b/arm/aarch64/include/kvm/kvm-config-arch.h
index 04be43dfa9b2..9968e1666de5 100644
--- a/arm/aarch64/include/kvm/kvm-config-arch.h
+++ b/arm/aarch64/include/kvm/kvm-config-arch.h
@@ -6,6 +6,8 @@
"Run AArch32 guest"), \
OPT_BOOLEAN('\0', "pmu", &(cfg)->has_pmuv3, \
"Create PMUv3 device"), \
+ OPT_BOOLEAN('\0', "spe", &(cfg)->has_spev1, \
+ "Create SPEv1 device"), \
OPT_U64('\0', "kaslr-seed", &(cfg)->kaslr_seed, \
"Specify random seed for Kernel Address Space " \
"Layout Randomization (KASLR)"),
diff --git a/arm/aarch64/include/kvm/kvm-cpu-arch.h b/arm/aarch64/include/kvm/kvm-cpu-arch.h
index 8dfb82ecbc37..080183fa4f81 100644
--- a/arm/aarch64/include/kvm/kvm-cpu-arch.h
+++ b/arm/aarch64/include/kvm/kvm-cpu-arch.h
@@ -8,7 +8,8 @@
#define ARM_VCPU_FEATURE_FLAGS(kvm, cpuid) { \
[0] = ((!!(cpuid) << KVM_ARM_VCPU_POWER_OFF) | \
(!!(kvm)->cfg.arch.aarch32_guest << KVM_ARM_VCPU_EL1_32BIT) | \
- (!!(kvm)->cfg.arch.has_pmuv3 << KVM_ARM_VCPU_PMU_V3)) \
+ (!!(kvm)->cfg.arch.has_pmuv3 << KVM_ARM_VCPU_PMU_V3) | \
+ (!!(kvm)->cfg.arch.has_spev1 << KVM_ARM_VCPU_SPE_V1)) \
}

#define ARM_MPIDR_HWID_BITMASK 0xFF00FFFFFFUL
diff --git a/arm/aarch64/kvm-cpu.c b/arm/aarch64/kvm-cpu.c
index 9f3e8586880c..90c2e1784e97 100644
--- a/arm/aarch64/kvm-cpu.c
+++ b/arm/aarch64/kvm-cpu.c
@@ -140,6 +140,10 @@ void kvm_cpu__select_features(struct kvm *kvm, struct kvm_vcpu_init *init)
/* Enable SVE if available */
if (kvm__supports_extension(kvm, KVM_CAP_ARM_SVE))
init->features[0] |= 1UL << KVM_ARM_VCPU_SVE;
+
+ /* Enable SPE if available */
+ if (kvm__supports_extension(kvm, KVM_CAP_ARM_SPE_V1))
+ init->features[0] |= 1UL << KVM_ARM_VCPU_SPE_V1;
}

int kvm_cpu__configure_features(struct kvm_cpu *vcpu)
diff --git a/arm/include/arm-common/kvm-config-arch.h b/arm/include/arm-common/kvm-config-arch.h
index 5734c46ab9e6..742733e289af 100644
--- a/arm/include/arm-common/kvm-config-arch.h
+++ b/arm/include/arm-common/kvm-config-arch.h
@@ -9,6 +9,7 @@ struct kvm_config_arch {
bool virtio_trans_pci;
bool aarch32_guest;
bool has_pmuv3;
+ bool has_spev1;
u64 kaslr_seed;
enum irqchip_type irqchip;
u64 fw_addr;
diff --git a/arm/include/arm-common/spe.h b/arm/include/arm-common/spe.h
new file mode 100644
index 000000000000..bcfa40877f6f
--- /dev/null
+++ b/arm/include/arm-common/spe.h
@@ -0,0 +1,4 @@
+
+#define KVM_ARM_SPEV1_PPI 21
+
+void spe__generate_fdt_nodes(void *fdt, struct kvm *kvm);
diff --git a/arm/spe.c b/arm/spe.c
new file mode 100644
index 000000000000..ec03b01a3866
--- /dev/null
+++ b/arm/spe.c
@@ -0,0 +1,81 @@
+#include "kvm/fdt.h"
+#include "kvm/kvm.h"
+#include "kvm/kvm-cpu.h"
+#include "kvm/util.h"
+
+#include "arm-common/gic.h"
+#include "arm-common/spe.h"
+
+#ifdef CONFIG_ARM64
+static int set_spe_attr(struct kvm *kvm, int vcpu_idx,
+ struct kvm_device_attr *attr)
+{
+ int ret, fd;
+
+ fd = kvm->cpus[vcpu_idx]->vcpu_fd;
+
+ ret = ioctl(fd, KVM_HAS_DEVICE_ATTR, attr);
+ if (!ret) {
+ ret = ioctl(fd, KVM_SET_DEVICE_ATTR, attr);
+ if (ret)
+ pr_err("SPE KVM_SET_DEVICE_ATTR failed (%d)\n", ret);
+ } else {
+ pr_err("Unsupported SPE on vcpu%d\n", vcpu_idx);
+ }
+
+ return ret;
+}
+
+void spe__generate_fdt_nodes(void *fdt, struct kvm *kvm)
+{
+ const char compatible[] = "arm,statistical-profiling-extension-v1";
+ int irq = KVM_ARM_SPEV1_PPI;
+ int i, ret;
+
+ u32 cpu_mask = (((1 << kvm->nrcpus) - 1) << GIC_FDT_IRQ_PPI_CPU_SHIFT) \
+ & GIC_FDT_IRQ_PPI_CPU_MASK;
+ u32 irq_prop[] = {
+ cpu_to_fdt32(GIC_FDT_IRQ_TYPE_PPI),
+ cpu_to_fdt32(irq - 16),
+ cpu_to_fdt32(cpu_mask | IRQ_TYPE_LEVEL_HIGH),
+ };
+
+ if (!kvm->cfg.arch.has_spev1)
+ return;
+
+ if (!kvm__supports_extension(kvm, KVM_CAP_ARM_SPE_V1)) {
+ pr_info("SPE unsupported\n");
+ return;
+ }
+
+ for (i = 0; i < kvm->nrcpus; i++) {
+ struct kvm_device_attr spe_attr;
+
+ spe_attr = (struct kvm_device_attr){
+ .group = KVM_ARM_VCPU_SPE_V1_CTRL,
+ .addr = (u64)(unsigned long)&irq,
+ .attr = KVM_ARM_VCPU_SPE_V1_IRQ,
+ };
+
+ ret = set_spe_attr(kvm, i, &spe_attr);
+ if (ret)
+ return;
+
+ spe_attr = (struct kvm_device_attr){
+ .group = KVM_ARM_VCPU_SPE_V1_CTRL,
+ .attr = KVM_ARM_VCPU_SPE_V1_INIT,
+ };
+
+ ret = set_spe_attr(kvm, i, &spe_attr);
+ if (ret)
+ return;
+ }
+
+ _FDT(fdt_begin_node(fdt, "spe"));
+ _FDT(fdt_property(fdt, "compatible", compatible, sizeof(compatible)));
+ _FDT(fdt_property(fdt, "interrupts", irq_prop, sizeof(irq_prop)));
+ _FDT(fdt_end_node(fdt));
+}
+#else
+void spe__generate_fdt_nodes(void *fdt, struct kvm *kvm) { }
+#endif
--
2.21.0