Commit 3d679d5a authored by Shuo Liu's avatar Shuo Liu Committed by Greg Kroah-Hartman
Browse files

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: default avatarZhi Wang <zhi.a.wang@intel.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: default avatarShuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-14-shuo.a.liu@intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c7cf8d27

drivers/virt/acrn/hsm.c

+69 −0
Original line number Diff line number Diff line
@@ -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;

drivers/virt/acrn/hypercall.h

+12 −0
Original line number Diff line number Diff line
@@ -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 */

include/uapi/linux/acrn.h

+55 −0
Original line number Diff line number Diff line
@@ -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 */