[linux.git] / drivers / xen / xen-acpi-processor.c

/*
 * Copyright 2012 by Oracle Inc
 * Author: Konrad Rzeszutek Wilk <[email protected]>
 *
 * This code borrows ideas from https://lkml.org/lkml/2011/11/30/249
 * so many thanks go to Kevin Tian <[email protected]>
 * and Yu Ke <[email protected]>.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/cpumask.h>
#include <linux/cpufreq.h>
#include <linux/freezer.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/acpi.h>
#include <acpi/processor.h>
#include <xen/xen.h>
#include <xen/xen-ops.h>
#include <xen/interface/platform.h>
#include <asm/xen/hypercall.h>

static int no_hypercall;
MODULE_PARM_DESC(off, "Inhibit the hypercall.");
module_param_named(off, no_hypercall, int, 0400);

/*
 * Note: Do not convert the acpi_id* below to cpumask_var_t or use cpumask_bit
 * - as those shrink to nr_cpu_bits (which is dependent on possible_cpu), which
 * can be less than what we want to put in. Instead use the 'nr_acpi_bits'
 * which is dynamically computed based on the MADT or x2APIC table.
 */
static unsigned int nr_acpi_bits;
/* Mutex to protect the acpi_ids_done - for CPU hotplug use. */
static DEFINE_MUTEX(acpi_ids_mutex);
/* Which ACPI ID we have processed from 'struct acpi_processor'. */
static unsigned long *acpi_ids_done;
/* Which ACPI ID exist in the SSDT/DSDT processor definitions. */
static unsigned long *acpi_id_present;
/* And if there is an _CST definition (or a PBLK) for the ACPI IDs */
static unsigned long *acpi_id_cst_present;

static int push_cxx_to_hypervisor(struct acpi_processor *_pr)
{
	struct xen_platform_op op = {
		.cmd			= XENPF_set_processor_pminfo,
		.interface_version	= XENPF_INTERFACE_VERSION,
		.u.set_pminfo.id	= _pr->acpi_id,
		.u.set_pminfo.type	= XEN_PM_CX,
	};
	struct xen_processor_cx *dst_cx, *dst_cx_states = NULL;
	struct acpi_processor_cx *cx;
	unsigned int i, ok;
	int ret = 0;

	dst_cx_states = kcalloc(_pr->power.count,
				sizeof(struct xen_processor_cx), GFP_KERNEL);
	if (!dst_cx_states)
		return -ENOMEM;

	for (ok = 0, i = 1; i <= _pr->power.count; i++) {
		cx = &_pr->power.states[i];
		if (!cx->valid)
			continue;

		dst_cx = &(dst_cx_states[ok++]);

		dst_cx->reg.space_id = ACPI_ADR_SPACE_SYSTEM_IO;
		if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
			dst_cx->reg.bit_width = 8;
			dst_cx->reg.bit_offset = 0;
			dst_cx->reg.access_size = 1;
		} else {
			dst_cx->reg.space_id = ACPI_ADR_SPACE_FIXED_HARDWARE;
			if (cx->entry_method == ACPI_CSTATE_FFH) {
				/* NATIVE_CSTATE_BEYOND_HALT */
				dst_cx->reg.bit_offset = 2;
				dst_cx->reg.bit_width = 1; /* VENDOR_INTEL */
			}
			dst_cx->reg.access_size = 0;
		}
		dst_cx->reg.address = cx->address;

		dst_cx->type = cx->type;
		dst_cx->latency = cx->latency;

		dst_cx->dpcnt = 0;
		set_xen_guest_handle(dst_cx->dp, NULL);
	}
	if (!ok) {
		pr_debug("No _Cx for ACPI CPU %u\n", _pr->acpi_id);
		kfree(dst_cx_states);
		return -EINVAL;
	}
	op.u.set_pminfo.power.count = ok;
	op.u.set_pminfo.power.flags.bm_control = _pr->flags.bm_control;
	op.u.set_pminfo.power.flags.bm_check = _pr->flags.bm_check;
	op.u.set_pminfo.power.flags.has_cst = _pr->flags.has_cst;
	op.u.set_pminfo.power.flags.power_setup_done =
		_pr->flags.power_setup_done;

	set_xen_guest_handle(op.u.set_pminfo.power.states, dst_cx_states);

	if (!no_hypercall)
		ret = HYPERVISOR_platform_op(&op);

	if (!ret) {
		pr_debug("ACPI CPU%u - C-states uploaded.\n", _pr->acpi_id);
		for (i = 1; i <= _pr->power.count; i++) {
			cx = &_pr->power.states[i];
			if (!cx->valid)
				continue;
			pr_debug("     C%d: %s %d uS\n",
				 cx->type, cx->desc, (u32)cx->latency);
		}
	} else if ((ret != -EINVAL) && (ret != -ENOSYS))
		/* EINVAL means the ACPI ID is incorrect - meaning the ACPI
		 * table is referencing a non-existing CPU - which can happen
		 * with broken ACPI tables. */
		pr_err("(CX): Hypervisor error (%d) for ACPI CPU%u\n",
		       ret, _pr->acpi_id);

	kfree(dst_cx_states);

	return ret;
}
static struct xen_processor_px *
xen_copy_pss_data(struct acpi_processor *_pr,
		  struct xen_processor_performance *dst_perf)
{
	struct xen_processor_px *dst_states = NULL;
	unsigned int i;

	BUILD_BUG_ON(sizeof(struct xen_processor_px) !=
		     sizeof(struct acpi_processor_px));

	dst_states = kcalloc(_pr->performance->state_count,
			     sizeof(struct xen_processor_px), GFP_KERNEL);
	if (!dst_states)
		return ERR_PTR(-ENOMEM);

	dst_perf->state_count = _pr->performance->state_count;
	for (i = 0; i < _pr->performance->state_count; i++) {
		/* Fortunatly for us, they are both the same size */
		memcpy(&(dst_states[i]), &(_pr->performance->states[i]),
		       sizeof(struct acpi_processor_px));
	}
	return dst_states;
}
static int xen_copy_psd_data(struct acpi_processor *_pr,
			     struct xen_processor_performance *dst)
{
	struct acpi_psd_package *pdomain;

	BUILD_BUG_ON(sizeof(struct xen_psd_package) !=
		     sizeof(struct acpi_psd_package));

	/* This information is enumerated only if acpi_processor_preregister_performance
	 * has been called.
	 */
	dst->shared_type = _pr->performance->shared_type;

	pdomain = &(_pr->performance->domain_info);

	/* 'acpi_processor_preregister_performance' does not parse if the
	 * num_processors <= 1, but Xen still requires it. Do it manually here.
	 */
	if (pdomain->num_processors <= 1) {
		if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
			dst->shared_type = CPUFREQ_SHARED_TYPE_ALL;
		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
			dst->shared_type = CPUFREQ_SHARED_TYPE_HW;
		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
			dst->shared_type = CPUFREQ_SHARED_TYPE_ANY;

	}
	memcpy(&(dst->domain_info), pdomain, sizeof(struct acpi_psd_package));
	return 0;
}
static int xen_copy_pct_data(struct acpi_pct_register *pct,
			     struct xen_pct_register *dst_pct)
{
	/* It would be nice if you could just do 'memcpy(pct, dst_pct') but
	 * sadly the Xen structure did not have the proper padding so the
	 * descriptor field takes two (dst_pct) bytes instead of one (pct).
	 */
	dst_pct->descriptor = pct->descriptor;
	dst_pct->length = pct->length;
	dst_pct->space_id = pct->space_id;
	dst_pct->bit_width = pct->bit_width;
	dst_pct->bit_offset = pct->bit_offset;
	dst_pct->reserved = pct->reserved;
	dst_pct->address = pct->address;
	return 0;
}
static int push_pxx_to_hypervisor(struct acpi_processor *_pr)
{
	int ret = 0;
	struct xen_platform_op op = {
		.cmd			= XENPF_set_processor_pminfo,
		.interface_version	= XENPF_INTERFACE_VERSION,
		.u.set_pminfo.id	= _pr->acpi_id,
		.u.set_pminfo.type	= XEN_PM_PX,
	};
	struct xen_processor_performance *dst_perf;
	struct xen_processor_px *dst_states = NULL;

	dst_perf = &op.u.set_pminfo.perf;

	dst_perf->platform_limit = _pr->performance_platform_limit;
	dst_perf->flags |= XEN_PX_PPC;
	xen_copy_pct_data(&(_pr->performance->control_register),
			  &dst_perf->control_register);
	xen_copy_pct_data(&(_pr->performance->status_register),
			  &dst_perf->status_register);
	dst_perf->flags |= XEN_PX_PCT;
	dst_states = xen_copy_pss_data(_pr, dst_perf);
	if (!IS_ERR_OR_NULL(dst_states)) {
		set_xen_guest_handle(dst_perf->states, dst_states);
		dst_perf->flags |= XEN_PX_PSS;
	}
	if (!xen_copy_psd_data(_pr, dst_perf))
		dst_perf->flags |= XEN_PX_PSD;

	if (dst_perf->flags != (XEN_PX_PSD | XEN_PX_PSS | XEN_PX_PCT | XEN_PX_PPC)) {
		pr_warn("ACPI CPU%u missing some P-state data (%x), skipping\n",
			_pr->acpi_id, dst_perf->flags);
		ret = -ENODEV;
		goto err_free;
	}

	if (!no_hypercall)
		ret = HYPERVISOR_platform_op(&op);

	if (!ret) {
		struct acpi_processor_performance *perf;
		unsigned int i;

		perf = _pr->performance;
		pr_debug("ACPI CPU%u - P-states uploaded.\n", _pr->acpi_id);
		for (i = 0; i < perf->state_count; i++) {
			pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
			(i == perf->state ? '*' : ' '), i,
			(u32) perf->states[i].core_frequency,
			(u32) perf->states[i].power,
			(u32) perf->states[i].transition_latency);
		}
	} else if ((ret != -EINVAL) && (ret != -ENOSYS))
		/* EINVAL means the ACPI ID is incorrect - meaning the ACPI
		 * table is referencing a non-existing CPU - which can happen
		 * with broken ACPI tables. */
		pr_warn("(_PXX): Hypervisor error (%d) for ACPI CPU%u\n",
			ret, _pr->acpi_id);
err_free:
	if (!IS_ERR_OR_NULL(dst_states))
		kfree(dst_states);

	return ret;
}
static int upload_pm_data(struct acpi_processor *_pr)
{
	int err = 0;

	mutex_lock(&acpi_ids_mutex);
	if (__test_and_set_bit(_pr->acpi_id, acpi_ids_done)) {
		mutex_unlock(&acpi_ids_mutex);
		return -EBUSY;
	}
	if (_pr->flags.power)
		err = push_cxx_to_hypervisor(_pr);

	if (_pr->performance && _pr->performance->states)
		err |= push_pxx_to_hypervisor(_pr);

	mutex_unlock(&acpi_ids_mutex);
	return err;
}
static unsigned int __init get_max_acpi_id(void)
{
	struct xenpf_pcpuinfo *info;
	struct xen_platform_op op = {
		.cmd = XENPF_get_cpuinfo,
		.interface_version = XENPF_INTERFACE_VERSION,
	};
	int ret = 0;
	unsigned int i, last_cpu, max_acpi_id = 0;

	info = &op.u.pcpu_info;
	info->xen_cpuid = 0;

	ret = HYPERVISOR_platform_op(&op);
	if (ret)
		return NR_CPUS;

	/* The max_present is the same irregardless of the xen_cpuid */
	last_cpu = op.u.pcpu_info.max_present;
	for (i = 0; i <= last_cpu; i++) {
		info->xen_cpuid = i;
		ret = HYPERVISOR_platform_op(&op);
		if (ret)
			continue;
		max_acpi_id = max(info->acpi_id, max_acpi_id);
	}
	max_acpi_id *= 2; /* Slack for CPU hotplug support. */
	pr_debug("Max ACPI ID: %u\n", max_acpi_id);
	return max_acpi_id;
}
/*
 * The read_acpi_id and check_acpi_ids are there to support the Xen
 * oddity of virtual CPUs != physical CPUs in the initial domain.
 * The user can supply 'xen_max_vcpus=X' on the Xen hypervisor line
 * which will band the amount of CPUs the initial domain can see.
 * In general that is OK, except it plays havoc with any of the
 * for_each_[present|online]_cpu macros which are banded to the virtual
 * CPU amount.
 */
static acpi_status
read_acpi_id(acpi_handle handle, u32 lvl, void *context, void **rv)
{
	u32 acpi_id;
	acpi_status status;
	acpi_object_type acpi_type;
	unsigned long long tmp;
	union acpi_object object = { 0 };
	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
	acpi_io_address pblk = 0;

	status = acpi_get_type(handle, &acpi_type);
	if (ACPI_FAILURE(status))
		return AE_OK;

	switch (acpi_type) {
	case ACPI_TYPE_PROCESSOR:
		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
		if (ACPI_FAILURE(status))
			return AE_OK;
		acpi_id = object.processor.proc_id;
		pblk = object.processor.pblk_address;
		break;
	case ACPI_TYPE_DEVICE:
		status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
		if (ACPI_FAILURE(status))
			return AE_OK;
		acpi_id = tmp;
		break;
	default:
		return AE_OK;
	}
	/* There are more ACPI Processor objects than in x2APIC or MADT.
	 * This can happen with incorrect ACPI SSDT declerations. */
	if (acpi_id > nr_acpi_bits) {
		pr_debug("We only have %u, trying to set %u\n",
			 nr_acpi_bits, acpi_id);
		return AE_OK;
	}
	/* OK, There is a ACPI Processor object */
	__set_bit(acpi_id, acpi_id_present);

	pr_debug("ACPI CPU%u w/ PBLK:0x%lx\n", acpi_id, (unsigned long)pblk);

	status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
	if (ACPI_FAILURE(status)) {
		if (!pblk)
			return AE_OK;
	}
	/* .. and it has a C-state */
	__set_bit(acpi_id, acpi_id_cst_present);

	return AE_OK;
}
static int check_acpi_ids(struct acpi_processor *pr_backup)
{

	if (!pr_backup)
		return -ENODEV;

	if (acpi_id_present && acpi_id_cst_present)
		/* OK, done this once .. skip to uploading */
		goto upload;

	/* All online CPUs have been processed at this stage. Now verify
	 * whether in fact "online CPUs" == physical CPUs.
	 */
	acpi_id_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
	if (!acpi_id_present)
		return -ENOMEM;

	acpi_id_cst_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
	if (!acpi_id_cst_present) {
		kfree(acpi_id_present);
		return -ENOMEM;
	}

	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
			    ACPI_UINT32_MAX,
			    read_acpi_id, NULL, NULL, NULL);
	acpi_get_devices("ACPI0007", read_acpi_id, NULL, NULL);

upload:
	if (!bitmap_equal(acpi_id_present, acpi_ids_done, nr_acpi_bits)) {
		unsigned int i;
		for_each_set_bit(i, acpi_id_present, nr_acpi_bits) {
			pr_backup->acpi_id = i;
			/* Mask out C-states if there are no _CST or PBLK */
			pr_backup->flags.power = test_bit(i, acpi_id_cst_present);
			(void)upload_pm_data(pr_backup);
		}
	}

	return 0;
}

/* acpi_perf_data is a pointer to percpu data. */
static struct acpi_processor_performance __percpu *acpi_perf_data;

static void free_acpi_perf_data(void)
{
	unsigned int i;

	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
	for_each_possible_cpu(i)
		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
				 ->shared_cpu_map);
	free_percpu(acpi_perf_data);
}

static int xen_upload_processor_pm_data(void)
{
	struct acpi_processor *pr_backup = NULL;
	unsigned int i;
	int rc = 0;

	pr_info("Uploading Xen processor PM info\n");

	for_each_possible_cpu(i) {
		struct acpi_processor *_pr;
		_pr = per_cpu(processors, i /* APIC ID */);
		if (!_pr)
			continue;

		if (!pr_backup) {
			pr_backup = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
			if (pr_backup)
				memcpy(pr_backup, _pr, sizeof(struct acpi_processor));
		}
		(void)upload_pm_data(_pr);
	}

	rc = check_acpi_ids(pr_backup);
	kfree(pr_backup);

	return rc;
}

static int xen_acpi_processor_resume(struct notifier_block *nb,
				     unsigned long action, void *data)
{
	bitmap_zero(acpi_ids_done, nr_acpi_bits);
	return xen_upload_processor_pm_data();
}

struct notifier_block xen_acpi_processor_resume_nb = {
	.notifier_call = xen_acpi_processor_resume,
};

static int __init xen_acpi_processor_init(void)
{
	unsigned int i;
	int rc;

	if (!xen_initial_domain())
		return -ENODEV;

	nr_acpi_bits = get_max_acpi_id() + 1;
	acpi_ids_done = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
	if (!acpi_ids_done)
		return -ENOMEM;

	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
	if (!acpi_perf_data) {
		pr_debug("Memory allocation error for acpi_perf_data\n");
		kfree(acpi_ids_done);
		return -ENOMEM;
	}
	for_each_possible_cpu(i) {
		if (!zalloc_cpumask_var_node(
			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
			GFP_KERNEL, cpu_to_node(i))) {
			rc = -ENOMEM;
			goto err_out;
		}
	}

	/* Do initialization in ACPI core. It is OK to fail here. */
	(void)acpi_processor_preregister_performance(acpi_perf_data);

	for_each_possible_cpu(i) {
		struct acpi_processor *pr;
		struct acpi_processor_performance *perf;

		pr = per_cpu(processors, i);
		perf = per_cpu_ptr(acpi_perf_data, i);
		if (!pr)
			continue;

		pr->performance = perf;
		rc = acpi_processor_get_performance_info(pr);
		if (rc)
			goto err_out;
	}

	rc = xen_upload_processor_pm_data();
	if (rc)
		goto err_unregister;

	xen_resume_notifier_register(&xen_acpi_processor_resume_nb);

	return 0;
err_unregister:
	for_each_possible_cpu(i)
		acpi_processor_unregister_performance(i);

err_out:
	/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
	free_acpi_perf_data();
	kfree(acpi_ids_done);
	return rc;
}
static void __exit xen_acpi_processor_exit(void)
{
	int i;

	xen_resume_notifier_unregister(&xen_acpi_processor_resume_nb);
	kfree(acpi_ids_done);
	kfree(acpi_id_present);
	kfree(acpi_id_cst_present);
	for_each_possible_cpu(i)
		acpi_processor_unregister_performance(i);

	free_acpi_perf_data();
}

MODULE_AUTHOR("Konrad Rzeszutek Wilk <[email protected]>");
MODULE_DESCRIPTION("Xen ACPI Processor P-states (and Cx) driver which uploads PM data to Xen hypervisor");
MODULE_LICENSE("GPL");

/* We want to be loaded before the CPU freq scaling drivers are loaded.
 * They are loaded in late_initcall. */
device_initcall(xen_acpi_processor_init);
module_exit(xen_acpi_processor_exit);
Commit	Line	Data
59a56802 KRW	1	/*
	2	* Copyright 2012 by Oracle Inc
	3	* Author: Konrad Rzeszutek Wilk <[email protected]>
	4	*
	5	* This code borrows ideas from https://lkml.org/lkml/2011/11/30/249
	6	* so many thanks go to Kevin Tian <[email protected]>
	7	* and Yu Ke <[email protected]>.
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms and conditions of the GNU General Public License,
	11	* version 2, as published by the Free Software Foundation.
	12	*
	13	* This program is distributed in the hope it will be useful, but WITHOUT
	14	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	15	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	16	* more details.
	17	*
	18	*/
	19
283c0972 JP	20	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
283c0972 JP	21
59a56802 KRW	22	#include <linux/cpumask.h>
	23	#include <linux/cpufreq.h>
	24	#include <linux/freezer.h>
	25	#include <linux/kernel.h>
	26	#include <linux/kthread.h>
	27	#include <linux/init.h>
	28	#include <linux/module.h>
	29	#include <linux/types.h>
8b48463f	30	#include <linux/acpi.h>
59a56802	31	#include <acpi/processor.h>
323f90a6	32	#include <xen/xen.h>
cd979883	33	#include <xen/xen-ops.h>
59a56802 KRW	34	#include <xen/interface/platform.h>
	35	#include <asm/xen/hypercall.h>
	36
59a56802 KRW	37	static int no_hypercall;
	38	MODULE_PARM_DESC(off, "Inhibit the hypercall.");
	39	module_param_named(off, no_hypercall, int, 0400);
	40
	41	/*
	42	* Note: Do not convert the acpi_id* below to cpumask_var_t or use cpumask_bit
	43	* - as those shrink to nr_cpu_bits (which is dependent on possible_cpu), which
	44	* can be less than what we want to put in. Instead use the 'nr_acpi_bits'
	45	* which is dynamically computed based on the MADT or x2APIC table.
	46	*/
	47	static unsigned int nr_acpi_bits;
	48	/* Mutex to protect the acpi_ids_done - for CPU hotplug use. */
	49	static DEFINE_MUTEX(acpi_ids_mutex);
	50	/* Which ACPI ID we have processed from 'struct acpi_processor'. */
	51	static unsigned long *acpi_ids_done;
	52	/* Which ACPI ID exist in the SSDT/DSDT processor definitions. */
3fac1014	53	static unsigned long *acpi_id_present;
59a56802	54	/* And if there is an _CST definition (or a PBLK) for the ACPI IDs */
3fac1014	55	static unsigned long *acpi_id_cst_present;
59a56802 KRW	56
	57	static int push_cxx_to_hypervisor(struct acpi_processor *_pr)
	58	{
	59	struct xen_platform_op op = {
	60	.cmd = XENPF_set_processor_pminfo,
	61	.interface_version = XENPF_INTERFACE_VERSION,
	62	.u.set_pminfo.id = _pr->acpi_id,
	63	.u.set_pminfo.type = XEN_PM_CX,
	64	};
	65	struct xen_processor_cx dst_cx, dst_cx_states = NULL;
	66	struct acpi_processor_cx *cx;
	67	unsigned int i, ok;
	68	int ret = 0;
	69
	70	dst_cx_states = kcalloc(_pr->power.count,
	71	sizeof(struct xen_processor_cx), GFP_KERNEL);
	72	if (!dst_cx_states)
	73	return -ENOMEM;
	74
	75	for (ok = 0, i = 1; i <= _pr->power.count; i++) {
	76	cx = &_pr->power.states[i];
	77	if (!cx->valid)
	78	continue;
	79
	80	dst_cx = &(dst_cx_states[ok++]);
	81
	82	dst_cx->reg.space_id = ACPI_ADR_SPACE_SYSTEM_IO;
	83	if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
	84	dst_cx->reg.bit_width = 8;
	85	dst_cx->reg.bit_offset = 0;
	86	dst_cx->reg.access_size = 1;
	87	} else {
	88	dst_cx->reg.space_id = ACPI_ADR_SPACE_FIXED_HARDWARE;
	89	if (cx->entry_method == ACPI_CSTATE_FFH) {
	90	/* NATIVE_CSTATE_BEYOND_HALT */
	91	dst_cx->reg.bit_offset = 2;
	92	dst_cx->reg.bit_width = 1; /* VENDOR_INTEL */
	93	}
	94	dst_cx->reg.access_size = 0;
	95	}
	96	dst_cx->reg.address = cx->address;
	97
	98	dst_cx->type = cx->type;
	99	dst_cx->latency = cx->latency;
59a56802 KRW	100
	101	dst_cx->dpcnt = 0;
	102	set_xen_guest_handle(dst_cx->dp, NULL);
	103	}
	104	if (!ok) {
283c0972	105	pr_debug("No _Cx for ACPI CPU %u\n", _pr->acpi_id);
59a56802 KRW	106	kfree(dst_cx_states);
	107	return -EINVAL;
	108	}
	109	op.u.set_pminfo.power.count = ok;
	110	op.u.set_pminfo.power.flags.bm_control = _pr->flags.bm_control;
	111	op.u.set_pminfo.power.flags.bm_check = _pr->flags.bm_check;
	112	op.u.set_pminfo.power.flags.has_cst = _pr->flags.has_cst;
	113	op.u.set_pminfo.power.flags.power_setup_done =
	114	_pr->flags.power_setup_done;
	115
	116	set_xen_guest_handle(op.u.set_pminfo.power.states, dst_cx_states);
	117
	118	if (!no_hypercall)
cfafae94	119	ret = HYPERVISOR_platform_op(&op);
59a56802 KRW	120
	121	if (!ret) {
	122	pr_debug("ACPI CPU%u - C-states uploaded.\n", _pr->acpi_id);
	123	for (i = 1; i <= _pr->power.count; i++) {
	124	cx = &_pr->power.states[i];
	125	if (!cx->valid)
	126	continue;
	127	pr_debug(" C%d: %s %d uS\n",
	128	cx->type, cx->desc, (u32)cx->latency);
	129	}
1a4b50f6	130	} else if ((ret != -EINVAL) && (ret != -ENOSYS))
b930fe5e KRW	131	/* EINVAL means the ACPI ID is incorrect - meaning the ACPI
	132	* table is referencing a non-existing CPU - which can happen
	133	* with broken ACPI tables. */
283c0972	134	pr_err("(CX): Hypervisor error (%d) for ACPI CPU%u\n",
59a56802 KRW	135	ret, _pr->acpi_id);
	136
	137	kfree(dst_cx_states);
	138
	139	return ret;
	140	}
	141	static struct xen_processor_px *
	142	xen_copy_pss_data(struct acpi_processor *_pr,
	143	struct xen_processor_performance *dst_perf)
	144	{
	145	struct xen_processor_px *dst_states = NULL;
	146	unsigned int i;
	147
	148	BUILD_BUG_ON(sizeof(struct xen_processor_px) !=
	149	sizeof(struct acpi_processor_px));
	150
	151	dst_states = kcalloc(_pr->performance->state_count,
	152	sizeof(struct xen_processor_px), GFP_KERNEL);
	153	if (!dst_states)
	154	return ERR_PTR(-ENOMEM);
	155
	156	dst_perf->state_count = _pr->performance->state_count;
	157	for (i = 0; i < _pr->performance->state_count; i++) {
	158	/* Fortunatly for us, they are both the same size */
	159	memcpy(&(dst_states[i]), &(_pr->performance->states[i]),
	160	sizeof(struct acpi_processor_px));
	161	}
	162	return dst_states;
	163	}
	164	static int xen_copy_psd_data(struct acpi_processor *_pr,
	165	struct xen_processor_performance *dst)
	166	{
	167	struct acpi_psd_package *pdomain;
	168
	169	BUILD_BUG_ON(sizeof(struct xen_psd_package) !=
	170	sizeof(struct acpi_psd_package));
	171
	172	/* This information is enumerated only if acpi_processor_preregister_performance
	173	* has been called.
	174	*/
	175	dst->shared_type = _pr->performance->shared_type;
	176
	177	pdomain = &(_pr->performance->domain_info);
	178
	179	/* 'acpi_processor_preregister_performance' does not parse if the
	180	* num_processors <= 1, but Xen still requires it. Do it manually here.
	181	*/
	182	if (pdomain->num_processors <= 1) {
	183	if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
	184	dst->shared_type = CPUFREQ_SHARED_TYPE_ALL;
	185	else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
	186	dst->shared_type = CPUFREQ_SHARED_TYPE_HW;
	187	else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
	188	dst->shared_type = CPUFREQ_SHARED_TYPE_ANY;
	189
	190	}
	191	memcpy(&(dst->domain_info), pdomain, sizeof(struct acpi_psd_package));
	192	return 0;
	193	}
	194	static int xen_copy_pct_data(struct acpi_pct_register *pct,
	195	struct xen_pct_register *dst_pct)
	196	{
	197	/* It would be nice if you could just do 'memcpy(pct, dst_pct') but
	198	* sadly the Xen structure did not have the proper padding so the
199	* descriptor field takes two (dst_pct) bytes instead of one (pct).
200	*/
201	dst_pct->descriptor = pct->descriptor;
202	dst_pct->length = pct->length;
203	dst_pct->space_id = pct->space_id;
204	dst_pct->bit_width = pct->bit_width;
205	dst_pct->bit_offset = pct->bit_offset;
206	dst_pct->reserved = pct->reserved;
207	dst_pct->address = pct->address;
208	return 0;
209	}
210	static int push_pxx_to_hypervisor(struct acpi_processor *_pr)
211	{
212	int ret = 0;
213	struct xen_platform_op op = {
214	.cmd = XENPF_set_processor_pminfo,
215	.interface_version = XENPF_INTERFACE_VERSION,
216	.u.set_pminfo.id = _pr->acpi_id,
217	.u.set_pminfo.type = XEN_PM_PX,
218	};
219	struct xen_processor_performance *dst_perf;
220	struct xen_processor_px *dst_states = NULL;
221
222	dst_perf = &op.u.set_pminfo.perf;
223
224	dst_perf->platform_limit = _pr->performance_platform_limit;
225	dst_perf->flags \|= XEN_PX_PPC;
226	xen_copy_pct_data(&(_pr->performance->control_register),
227	&dst_perf->control_register);
228	xen_copy_pct_data(&(_pr->performance->status_register),
229	&dst_perf->status_register);
230	dst_perf->flags \|= XEN_PX_PCT;
231	dst_states = xen_copy_pss_data(_pr, dst_perf);
232	if (!IS_ERR_OR_NULL(dst_states)) {
233	set_xen_guest_handle(dst_perf->states, dst_states);
234	dst_perf->flags \|= XEN_PX_PSS;
235	}
236	if (!xen_copy_psd_data(_pr, dst_perf))
237	dst_perf->flags \|= XEN_PX_PSD;
238
239	if (dst_perf->flags != (XEN_PX_PSD \| XEN_PX_PSS \| XEN_PX_PCT \| XEN_PX_PPC)) {
283c0972	240	pr_warn("ACPI CPU%u missing some P-state data (%x), skipping\n",
59a56802 KRW	241	_pr->acpi_id, dst_perf->flags);
	242	ret = -ENODEV;
	243	goto err_free;
	244	}
	245
	246	if (!no_hypercall)
cfafae94	247	ret = HYPERVISOR_platform_op(&op);
59a56802 KRW	248
	249	if (!ret) {
	250	struct acpi_processor_performance *perf;
	251	unsigned int i;
	252
	253	perf = _pr->performance;
	254	pr_debug("ACPI CPU%u - P-states uploaded.\n", _pr->acpi_id);
	255	for (i = 0; i < perf->state_count; i++) {
	256	pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
	257	(i == perf->state ? '*' : ' '), i,
	258	(u32) perf->states[i].core_frequency,
	259	(u32) perf->states[i].power,
	260	(u32) perf->states[i].transition_latency);
	261	}
1a4b50f6	262	} else if ((ret != -EINVAL) && (ret != -ENOSYS))
59a56802 KRW	263	/* EINVAL means the ACPI ID is incorrect - meaning the ACPI
	264	* table is referencing a non-existing CPU - which can happen
	265	* with broken ACPI tables. */
283c0972 JP	266	pr_warn("(_PXX): Hypervisor error (%d) for ACPI CPU%u\n",
283c0972 JP	267	ret, _pr->acpi_id);
59a56802 KRW	268	err_free:
	269	if (!IS_ERR_OR_NULL(dst_states))
	270	kfree(dst_states);
	271
	272	return ret;
	273	}
	274	static int upload_pm_data(struct acpi_processor *_pr)
	275	{
	276	int err = 0;
	277
	278	mutex_lock(&acpi_ids_mutex);
	279	if (__test_and_set_bit(_pr->acpi_id, acpi_ids_done)) {
	280	mutex_unlock(&acpi_ids_mutex);
	281	return -EBUSY;
	282	}
	283	if (_pr->flags.power)
	284	err = push_cxx_to_hypervisor(_pr);
	285
	286	if (_pr->performance && _pr->performance->states)
	287	err \|= push_pxx_to_hypervisor(_pr);
	288
	289	mutex_unlock(&acpi_ids_mutex);
	290	return err;
	291	}
	292	static unsigned int __init get_max_acpi_id(void)
	293	{
	294	struct xenpf_pcpuinfo *info;
	295	struct xen_platform_op op = {
	296	.cmd = XENPF_get_cpuinfo,
	297	.interface_version = XENPF_INTERFACE_VERSION,
	298	};
	299	int ret = 0;
	300	unsigned int i, last_cpu, max_acpi_id = 0;
	301
	302	info = &op.u.pcpu_info;
	303	info->xen_cpuid = 0;
	304
cfafae94	305	ret = HYPERVISOR_platform_op(&op);
59a56802 KRW	306	if (ret)
	307	return NR_CPUS;
	308
	309	/* The max_present is the same irregardless of the xen_cpuid */
	310	last_cpu = op.u.pcpu_info.max_present;
	311	for (i = 0; i <= last_cpu; i++) {
	312	info->xen_cpuid = i;
cfafae94	313	ret = HYPERVISOR_platform_op(&op);
59a56802 KRW	314	if (ret)
	315	continue;
	316	max_acpi_id = max(info->acpi_id, max_acpi_id);
	317	}
	318	max_acpi_id = 2; / Slack for CPU hotplug support. */
283c0972	319	pr_debug("Max ACPI ID: %u\n", max_acpi_id);
59a56802 KRW	320	return max_acpi_id;
	321	}
	322	/*
	323	* The read_acpi_id and check_acpi_ids are there to support the Xen
	324	* oddity of virtual CPUs != physical CPUs in the initial domain.
	325	* The user can supply 'xen_max_vcpus=X' on the Xen hypervisor line
	326	* which will band the amount of CPUs the initial domain can see.
	327	* In general that is OK, except it plays havoc with any of the
	328	* for_each_[present\|online]_cpu macros which are banded to the virtual
	329	* CPU amount.
	330	*/
18c0025b	331	static acpi_status
59a56802 KRW	332	read_acpi_id(acpi_handle handle, u32 lvl, void context, void *rv)
	333	{
	334	u32 acpi_id;
	335	acpi_status status;
	336	acpi_object_type acpi_type;
	337	unsigned long long tmp;
	338	union acpi_object object = { 0 };
	339	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
	340	acpi_io_address pblk = 0;
	341
	342	status = acpi_get_type(handle, &acpi_type);
	343	if (ACPI_FAILURE(status))
	344	return AE_OK;
	345
	346	switch (acpi_type) {
	347	case ACPI_TYPE_PROCESSOR:
	348	status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
	349	if (ACPI_FAILURE(status))
	350	return AE_OK;
	351	acpi_id = object.processor.proc_id;
	352	pblk = object.processor.pblk_address;
	353	break;
	354	case ACPI_TYPE_DEVICE:
	355	status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
	356	if (ACPI_FAILURE(status))
	357	return AE_OK;
	358	acpi_id = tmp;
	359	break;
	360	default:
	361	return AE_OK;
	362	}
	363	/* There are more ACPI Processor objects than in x2APIC or MADT.
	364	* This can happen with incorrect ACPI SSDT declerations. */
	365	if (acpi_id > nr_acpi_bits) {
283c0972	366	pr_debug("We only have %u, trying to set %u\n",
59a56802 KRW	367	nr_acpi_bits, acpi_id);
	368	return AE_OK;
	369	}
	370	/* OK, There is a ACPI Processor object */
	371	__set_bit(acpi_id, acpi_id_present);
	372
283c0972	373	pr_debug("ACPI CPU%u w/ PBLK:0x%lx\n", acpi_id, (unsigned long)pblk);
59a56802 KRW	374
	375	status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
	376	if (ACPI_FAILURE(status)) {
	377	if (!pblk)
	378	return AE_OK;
	379	}
	380	/* .. and it has a C-state */
	381	__set_bit(acpi_id, acpi_id_cst_present);
	382
	383	return AE_OK;
	384	}
18c0025b	385	static int check_acpi_ids(struct acpi_processor *pr_backup)
59a56802 KRW	386	{
	387
	388	if (!pr_backup)
	389	return -ENODEV;
	390
3fac1014 BG	391	if (acpi_id_present && acpi_id_cst_present)
	392	/* OK, done this once .. skip to uploading */
	393	goto upload;
	394
59a56802 KRW	395	/* All online CPUs have been processed at this stage. Now verify
	396	* whether in fact "online CPUs" == physical CPUs.
	397	*/
	398	acpi_id_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
	399	if (!acpi_id_present)
	400	return -ENOMEM;
	401
	402	acpi_id_cst_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
	403	if (!acpi_id_cst_present) {
	404	kfree(acpi_id_present);
	405	return -ENOMEM;
	406	}
	407
	408	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
	409	ACPI_UINT32_MAX,
	410	read_acpi_id, NULL, NULL, NULL);
	411	acpi_get_devices("ACPI0007", read_acpi_id, NULL, NULL);
	412
3fac1014	413	upload:
59a56802 KRW	414	if (!bitmap_equal(acpi_id_present, acpi_ids_done, nr_acpi_bits)) {
	415	unsigned int i;
	416	for_each_set_bit(i, acpi_id_present, nr_acpi_bits) {
	417	pr_backup->acpi_id = i;
	418	/* Mask out C-states if there are no _CST or PBLK */
	419	pr_backup->flags.power = test_bit(i, acpi_id_cst_present);
	420	(void)upload_pm_data(pr_backup);
	421	}
	422	}
3fac1014	423
59a56802 KRW	424	return 0;
59a56802 KRW	425	}
59a56802	426
59a56802 KRW	427	/* acpi_perf_data is a pointer to percpu data. */
	428	static struct acpi_processor_performance __percpu *acpi_perf_data;
	429
	430	static void free_acpi_perf_data(void)
	431	{
	432	unsigned int i;
	433
	434	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
	435	for_each_possible_cpu(i)
	436	free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
	437	->shared_cpu_map);
	438	free_percpu(acpi_perf_data);
	439	}
	440
3fac1014	441	static int xen_upload_processor_pm_data(void)
59a56802 KRW	442	{
59a56802 KRW	443	struct acpi_processor *pr_backup = NULL;
3fac1014 BG	444	unsigned int i;
	445	int rc = 0;
	446
283c0972	447	pr_info("Uploading Xen processor PM info\n");
3fac1014 BG	448
	449	for_each_possible_cpu(i) {
	450	struct acpi_processor *_pr;
	451	_pr = per_cpu(processors, i /* APIC ID */);
	452	if (!_pr)
	453	continue;
	454
	455	if (!pr_backup) {
	456	pr_backup = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
	457	if (pr_backup)
	458	memcpy(pr_backup, _pr, sizeof(struct acpi_processor));
	459	}
	460	(void)upload_pm_data(_pr);
	461	}
	462
	463	rc = check_acpi_ids(pr_backup);
	464	kfree(pr_backup);
	465
	466	return rc;
	467	}
	468
cd979883 SG	469	static int xen_acpi_processor_resume(struct notifier_block *nb,
cd979883 SG	470	unsigned long action, void *data)
3fac1014 BG	471	{
3fac1014 BG	472	bitmap_zero(acpi_ids_done, nr_acpi_bits);
cd979883	473	return xen_upload_processor_pm_data();
3fac1014 BG	474	}
3fac1014 BG	475
cd979883 SG	476	struct notifier_block xen_acpi_processor_resume_nb = {
cd979883 SG	477	.notifier_call = xen_acpi_processor_resume,
3fac1014 BG	478	};
	479
	480	static int __init xen_acpi_processor_init(void)
	481	{
59a56802	482	unsigned int i;
6f2d9d99	483	int rc;
59a56802	484
6f2d9d99 JB	485	if (!xen_initial_domain())
6f2d9d99 JB	486	return -ENODEV;
59a56802 KRW	487
	488	nr_acpi_bits = get_max_acpi_id() + 1;
	489	acpi_ids_done = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
	490	if (!acpi_ids_done)
	491	return -ENOMEM;
	492
	493	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
	494	if (!acpi_perf_data) {
283c0972	495	pr_debug("Memory allocation error for acpi_perf_data\n");
59a56802 KRW	496	kfree(acpi_ids_done);
	497	return -ENOMEM;
	498	}
	499	for_each_possible_cpu(i) {
	500	if (!zalloc_cpumask_var_node(
	501	&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
	502	GFP_KERNEL, cpu_to_node(i))) {
	503	rc = -ENOMEM;
	504	goto err_out;
	505	}
	506	}
	507
	508	/* Do initialization in ACPI core. It is OK to fail here. */
	509	(void)acpi_processor_preregister_performance(acpi_perf_data);
	510
	511	for_each_possible_cpu(i) {
c705c78c	512	struct acpi_processor *pr;
59a56802 KRW	513	struct acpi_processor_performance *perf;
59a56802 KRW	514
c705c78c	515	pr = per_cpu(processors, i);
59a56802	516	perf = per_cpu_ptr(acpi_perf_data, i);
949dd8c1 KRW	517	if (!pr)
	518	continue;
	519
c705c78c KRW	520	pr->performance = perf;
c705c78c KRW	521	rc = acpi_processor_get_performance_info(pr);
27257fc0	522	if (rc)
59a56802 KRW	523	goto err_out;
59a56802 KRW	524	}
59a56802	525
3fac1014	526	rc = xen_upload_processor_pm_data();
17f9b896 KRW	527	if (rc)
17f9b896 KRW	528	goto err_unregister;
59a56802	529
cd979883	530	xen_resume_notifier_register(&xen_acpi_processor_resume_nb);
3fac1014	531
59a56802 KRW	532	return 0;
59a56802 KRW	533	err_unregister:
b2f8dc4c RW	534	for_each_possible_cpu(i)
	535	acpi_processor_unregister_performance(i);
	536
59a56802 KRW	537	err_out:
	538	/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
	539	free_acpi_perf_data();
	540	kfree(acpi_ids_done);
	541	return rc;
	542	}
	543	static void __exit xen_acpi_processor_exit(void)
	544	{
	545	int i;
	546
cd979883	547	xen_resume_notifier_unregister(&xen_acpi_processor_resume_nb);
59a56802	548	kfree(acpi_ids_done);
3fac1014 BG	549	kfree(acpi_id_present);
3fac1014 BG	550	kfree(acpi_id_cst_present);
b2f8dc4c RW	551	for_each_possible_cpu(i)
	552	acpi_processor_unregister_performance(i);
	553
59a56802 KRW	554	free_acpi_perf_data();
	555	}
	556
	557	MODULE_AUTHOR("Konrad Rzeszutek Wilk <[email protected]>");
	558	MODULE_DESCRIPTION("Xen ACPI Processor P-states (and Cx) driver which uploads PM data to Xen hypervisor");
	559	MODULE_LICENSE("GPL");
	560
	561	/* We want to be loaded before the CPU freq scaling drivers are loaded.
	562	* They are loaded in late_initcall. */
	563	device_initcall(xen_acpi_processor_init);
	564	module_exit(xen_acpi_processor_exit);