[PATCH v6 13/18] virt: acrn: Introduce interfaces to query C-states and P-states allowed by hypervisor

shuo.a.liu
2020-12-01T09:41:48Z

The C-states and P-states data are used to support CPU power management.
The hypervisor controls C-states and P-states for a User VM.

ACRN userspace need to query the data from the hypervisor to build ACPI
tables for a User VM.

HSM provides ioctls for ACRN userspace to query C-states and P-states
data obtained from the hypervisor.

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/virt/acrn/hsm.c | 69 +++++++++++++++++++++++++++++++++++
drivers/virt/acrn/hypercall.h | 12 ++++++
include/uapi/linux/acrn.h | 35 ++++++++++++++++++
3 files changed, 116 insertions(+)

diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index 43fb2e32108c..700006e2465b 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -38,6 +38,67 @@ static int acrn_dev_open(struct inode *inode, struct file *filp)
return 0;
}

+static int pmcmd_ioctl(u64 cmd, void __user *uptr)
+{
+ struct acrn_pstate_data *px_data;
+ struct acrn_cstate_data *cx_data;
+ u64 *pm_info;
+ int ret = 0;
+
+ switch (cmd & PMCMD_TYPE_MASK) {
+ case ACRN_PMCMD_GET_PX_CNT:
+ case ACRN_PMCMD_GET_CX_CNT:
+ pm_info = kmalloc(sizeof(u64), GFP_KERNEL);
+ if (!pm_info)
+ return -ENOMEM;
+
+ ret = hcall_get_cpu_state(cmd, virt_to_phys(pm_info));
+ if (ret < 0) {
+ kfree(pm_info);
+ break;
+ }
+
+ if (copy_to_user(uptr, pm_info, sizeof(u64)))
+ ret = -EFAULT;
+ kfree(pm_info);
+ break;
+ case ACRN_PMCMD_GET_PX_DATA:
+ px_data = kmalloc(sizeof(*px_data), GFP_KERNEL);
+ if (!px_data)
+ return -ENOMEM;
+
+ ret = hcall_get_cpu_state(cmd, virt_to_phys(px_data));
+ if (ret < 0) {
+ kfree(px_data);
+ break;
+ }
+
+ if (copy_to_user(uptr, px_data, sizeof(*px_data)))
+ ret = -EFAULT;
+ kfree(px_data);
+ break;
+ case ACRN_PMCMD_GET_CX_DATA:
+ cx_data = kmalloc(sizeof(*cx_data), GFP_KERNEL);
+ if (!cx_data)
+ return -ENOMEM;
+
+ ret = hcall_get_cpu_state(cmd, virt_to_phys(cx_data));
+ if (ret < 0) {
+ kfree(cx_data);
+ break;
+ }
+
+ if (copy_to_user(uptr, cx_data, sizeof(*cx_data)))
+ ret = -EFAULT;
+ kfree(cx_data);
+ break;
+ default:
+ break;
+ }
+
+ return ret;
+}
+
/*
* HSM relies on hypercall layer of the ACRN hypervisor to do the
* sanity check against the input parameters.
@@ -54,6 +115,7 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
struct acrn_msi_entry *msi;
struct acrn_pcidev *pcidev;
struct page *page;
+ u64 cstate_cmd;
int ret = 0;

if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) {
@@ -246,6 +308,13 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
case ACRN_IOCTL_CLEAR_VM_IOREQ:
acrn_ioreq_request_clear(vm);
break;
+ case ACRN_IOCTL_PM_GET_CPU_STATE:
+ if (copy_from_user(&cstate_cmd, (void *)ioctl_param,
+ sizeof(cstate_cmd)))
+ return -EFAULT;
+
+ ret = pmcmd_ioctl(cstate_cmd, (void __user *)ioctl_param);
+ break;
default:
dev_dbg(acrn_dev.this_device, "Unknown IOCTL 0x%x!\n", cmd);
ret = -ENOTTY;
diff --git a/drivers/virt/acrn/hypercall.h b/drivers/virt/acrn/hypercall.h
index a8813397a3fe..e640632366f0 100644
--- a/drivers/virt/acrn/hypercall.h
+++ b/drivers/virt/acrn/hypercall.h
@@ -39,6 +39,9 @@
#define HC_ASSIGN_PCIDEV _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x05)
#define HC_DEASSIGN_PCIDEV _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x06)

+#define HC_ID_PM_BASE 0x80UL
+#define HC_PM_GET_CPU_STATE _HC_ID(HC_ID, HC_ID_PM_BASE + 0x00)
+
/**
* hcall_create_vm() - Create a User VM
* @vminfo: Service VM GPA of info of User VM creation
@@ -225,4 +228,13 @@ static inline long hcall_reset_ptdev_intr(u64 vmid, u64 irq)
return acrn_hypercall2(HC_RESET_PTDEV_INTR, vmid, irq);
}

+/*
+ * hcall_get_cpu_state() - Get P-states and C-states info from the hypervisor
+ * @state: Service VM GPA of buffer of P-states and C-states
+ */
+static inline long hcall_get_cpu_state(u64 cmd, u64 state)
+{
+ return acrn_hypercall2(HC_PM_GET_CPU_STATE, cmd, state);
+}
+
#endif /* __ACRN_HSM_HYPERCALL_H */
diff --git a/include/uapi/linux/acrn.h b/include/uapi/linux/acrn.h
index 959dfbccc6a4..cb584f61056b 100644
--- a/include/uapi/linux/acrn.h
+++ b/include/uapi/linux/acrn.h
@@ -346,6 +346,38 @@ struct acrn_msi_entry {
__u64 msi_data;
};

+struct acrn_acpi_generic_address {
+ __u8 space_id;
+ __u8 bit_width;
+ __u8 bit_offset;
+ __u8 access_size;
+ __u64 address;
+} __attribute__ ((__packed__));
+
+struct acrn_cstate_data {
+ struct acrn_acpi_generic_address cx_reg;
+ __u8 type;
+ __u32 latency;
+ __u64 power;
+};
+
+struct acrn_pstate_data {
+ __u64 core_frequency;
+ __u64 power;
+ __u64 transition_latency;
+ __u64 bus_master_latency;
+ __u64 control;
+ __u64 status;
+};
+
+#define PMCMD_TYPE_MASK 0x000000ff
+enum acrn_pm_cmd_type {
+ ACRN_PMCMD_GET_PX_CNT,
+ ACRN_PMCMD_GET_PX_DATA,
+ ACRN_PMCMD_GET_CX_CNT,
+ ACRN_PMCMD_GET_CX_DATA,
+};
+
/* The ioctl type, documented in ioctl-number.rst */
#define ACRN_IOCTL_TYPE 0xA2

@@ -397,4 +429,7 @@ struct acrn_msi_entry {
#define ACRN_IOCTL_DEASSIGN_PCIDEV \
_IOW(ACRN_IOCTL_TYPE, 0x56, struct acrn_pcidev)

+#define ACRN_IOCTL_PM_GET_CPU_STATE \
+ _IOWR(ACRN_IOCTL_TYPE, 0x60, __u64)
+
#endif /* _UAPI_ACRN_H */
--
2.28.0