[Qemu-devel] [PATCH v4 2/3] hw/arm/virt: Add PMU node for virt machine

[Shannon Zhao <zhaoshenglong@huawei.com>]

From: Shannon Zhao <shannon.zhao@linaro.org>

Add a virtual PMU device for virt machine while use PPI 7 for PMU
overflow interrupt number.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
---
 hw/arm/virt.c         | 33 +++++++++++++++++++++++++++++++++
 include/hw/arm/virt.h |  4 ++++
 include/sysemu/kvm.h  |  1 +
 stubs/kvm.c           |  5 +++++
 target-arm/kvm64.c    | 41 +++++++++++++++++++++++++++++++++++++++++
 5 files changed, 84 insertions(+)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 56d35c7..376cb87 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -428,6 +428,37 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type)
     qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
 }
 
+static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype)
+{
+    CPUState *cpu;
+    ARMCPU *armcpu;
+    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
+
+    CPU_FOREACH(cpu) {
+        armcpu = ARM_CPU(cpu);
+        if (!armcpu->has_pmu ||
+            !kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ))) {
+            return;
+        }
+    }
+
+    if (gictype == 2) {
+        irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
+                             GIC_FDT_IRQ_PPI_CPU_WIDTH,
+                             (1 << vbi->smp_cpus) - 1);
+    }
+
+    armcpu = ARM_CPU(qemu_get_cpu(0));
+    qemu_fdt_add_subnode(vbi->fdt, "/pmu");
+    if (arm_feature(&armcpu->env, ARM_FEATURE_V8)) {
+        const char compat[] = "arm,armv8-pmuv3";
+        qemu_fdt_setprop(vbi->fdt, "/pmu", "compatible",
+                         compat, sizeof(compat));
+        qemu_fdt_setprop_cells(vbi->fdt, "/pmu", "interrupts",
+                               GIC_FDT_IRQ_TYPE_PPI, VIRTUAL_PMU_IRQ, irqflags);
+    }
+}
+
 static void create_v2m(VirtBoardInfo *vbi, qemu_irq *pic)
 {
     int i;
@@ -1246,6 +1277,8 @@ static void machvirt_init(MachineState *machine)
 
     create_gic(vbi, pic, gic_version, vms->secure);
 
+    fdt_add_pmu_nodes(vbi, gic_version);
+
     create_uart(vbi, pic, VIRT_UART, sysmem);
 
     if (vms->secure) {
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index ecd8589..b50f095 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -40,6 +40,10 @@
 #define ARCH_TIMER_NS_EL1_IRQ 14
 #define ARCH_TIMER_NS_EL2_IRQ 10
 
+#define VIRTUAL_PMU_IRQ 7
+
+#define PPI(irq) ((irq) + 16)
+
 enum {
     VIRT_FLASH,
     VIRT_MEM,
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index 0e18f15..4522043 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -523,4 +523,5 @@ int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source);
  * Returns: 0 on success, or a negative errno on failure.
  */
 int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target);
+int kvm_arm_pmu_create(CPUState *cs, int irq);
 #endif
diff --git a/stubs/kvm.c b/stubs/kvm.c
index ddd6204..667e269 100644
--- a/stubs/kvm.c
+++ b/stubs/kvm.c
@@ -6,3 +6,8 @@ int kvm_arch_irqchip_create(MachineState *ms, KVMState *s)
 {
     return 0;
 }
+
+int kvm_arm_pmu_create(CPUState *cs, int irq)
+{
+    return 0;
+}
diff --git a/target-arm/kvm64.c b/target-arm/kvm64.c
index b364789..893f983 100644
--- a/target-arm/kvm64.c
+++ b/target-arm/kvm64.c
@@ -382,6 +382,47 @@ static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr)
     return NULL;
 }
 
+static bool kvm_arm_pmu_support_ctrl(CPUState *cs, struct kvm_device_attr *attr)
+{
+    return kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr) == 0;
+}
+
+int kvm_arm_pmu_create(CPUState *cs, int irq)
+{
+    int err;
+
+    struct kvm_device_attr attr = {
+        .group = KVM_ARM_VCPU_PMU_V3_CTRL,
+        .addr = (intptr_t)&irq,
+        .attr = KVM_ARM_VCPU_PMU_V3_IRQ,
+        .flags = 0,
+    };
+
+    if (!kvm_arm_pmu_support_ctrl(cs, &attr)) {
+        return 0;
+    }
+
+    err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr);
+    if (err < 0) {
+        fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n",
+                strerror(-err));
+        abort();
+    }
+
+    attr.group = KVM_ARM_VCPU_PMU_V3_CTRL;
+    attr.attr = KVM_ARM_VCPU_PMU_V3_INIT;
+    attr.addr = 0;
+    attr.flags = 0;
+
+    err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr);
+    if (err < 0) {
+        fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n",
+                strerror(-err));
+        abort();
+    }
+
+    return 1;
+}
 
 static inline void set_feature(uint64_t *features, int feature)
 {
-- 
2.0.4