virt: acrn: Introduce interfaces to query C-states and P-states allowed by hypervisor

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.

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>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-14-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index 419271f32be88198a58f0a916a04ee376c82b513..b7f2deddc3e79ba6c83e02b698e8661b2acaeb6d 100644 (file)
--- 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 i, ret = 0;
 
        if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) {
@@ -267,6 +329,13 @@ 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 a8813397a3fe3efc189fb471a774363797442656..e640632366f0deb61ba92f1960295f7572b33279 100644 (file)
--- 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 b1c06b28ebdca195ed69b17da0d9fb87763bddbd..e997d80a0cc7a485a5c7d5bbbd327371003d8fcd 100644 (file)
--- a/include/uapi/linux/acrn.h
+++ b/include/uapi/linux/acrn.h
@@ -427,6 +427,58 @@ 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 - A C state package defined in ACPI
+ * @cx_reg:    Register of the C state object
+ * @type:      Type of the C state object
+ * @latency:   The worst-case latency to enter and exit this C state
+ * @power:     The average power consumption when in this C state
+ */
+struct acrn_cstate_data {
+       struct acrn_acpi_generic_address        cx_reg;
+       __u8                                    type;
+       __u32                                   latency;
+       __u64                                   power;
+};
+
+/**
+ * struct acrn_pstate_data - A P state package defined in ACPI
+ * @core_frequency:    CPU frequency (in MHz).
+ * @power:             Power dissipation (in milliwatts).
+ * @transition_latency:        The worst-case latency in microseconds that CPU is
+ *                     unavailable during a transition from any P state to
+ *                     this P state.
+ * @bus_master_latency:        The worst-case latency in microseconds that Bus Masters
+ *                     are prevented from accessing memory during a transition
+ *                     from any P state to this P state.
+ * @control:           The value to be written to Performance Control Register
+ * @status:            Transition status.
+ */
+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
 
@@ -478,4 +530,7 @@ 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 */