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-rw-r--r--drivers/xen/xen-acpi-processor.c604
1 files changed, 604 insertions, 0 deletions
diff --git a/drivers/xen/xen-acpi-processor.c b/drivers/xen/xen-acpi-processor.c
new file mode 100644
index 000000000..9cb61db67
--- /dev/null
+++ b/drivers/xen/xen-acpi-processor.c
@@ -0,0 +1,604 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2012 by Oracle Inc
+ * Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
+ *
+ * This code borrows ideas from
+ * https://lore.kernel.org/lkml/1322673664-14642-6-git-send-email-konrad.wilk@oracle.com
+ * so many thanks go to Kevin Tian <kevin.tian@intel.com>
+ * and Yu Ke <ke.yu@intel.com>.
+ */
+
+#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/syscore_ops.h>
+#include <linux/acpi.h>
+#include <acpi/processor.h>
+#include <xen/xen.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;
+/* Which ACPI P-State dependencies for a enumerated processor */
+static struct acpi_psd_package *acpi_psd;
+
+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;
+ }
+ if (invalid_phys_cpuid(acpi_get_phys_id(handle,
+ acpi_type == ACPI_TYPE_DEVICE,
+ acpi_id))) {
+ pr_debug("CPU with ACPI ID %u is unavailable\n", acpi_id);
+ 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("max acpi id %u, trying to set %u\n",
+ nr_acpi_bits - 1, 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);
+
+ /* It has P-state dependencies */
+ if (!acpi_processor_get_psd(handle, &acpi_psd[acpi_id])) {
+ pr_debug("ACPI CPU%u w/ PST:coord_type = %llu domain = %llu\n",
+ acpi_id, acpi_psd[acpi_id].coord_type,
+ acpi_psd[acpi_id].domain);
+ }
+
+ 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 = bitmap_zalloc(nr_acpi_bits, GFP_KERNEL);
+ if (!acpi_id_present)
+ return -ENOMEM;
+
+ acpi_id_cst_present = bitmap_zalloc(nr_acpi_bits, GFP_KERNEL);
+ if (!acpi_id_cst_present) {
+ bitmap_free(acpi_id_present);
+ return -ENOMEM;
+ }
+
+ acpi_psd = kcalloc(nr_acpi_bits, sizeof(struct acpi_psd_package),
+ GFP_KERNEL);
+ if (!acpi_psd) {
+ bitmap_free(acpi_id_present);
+ bitmap_free(acpi_id_cst_present);
+ return -ENOMEM;
+ }
+
+ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
+ ACPI_UINT32_MAX,
+ read_acpi_id, NULL, NULL, NULL);
+ acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, 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);
+ /* num_entries is non-zero if we evaluated _PSD */
+ if (acpi_psd[i].num_entries) {
+ memcpy(&pr_backup->performance->domain_info,
+ &acpi_psd[i],
+ sizeof(struct acpi_psd_package));
+ }
+ (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)
+{
+ 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;
+ 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 void xen_acpi_processor_resume_worker(struct work_struct *dummy)
+{
+ int rc;
+
+ bitmap_zero(acpi_ids_done, nr_acpi_bits);
+
+ rc = xen_upload_processor_pm_data();
+ if (rc != 0)
+ pr_info("ACPI data upload failed, error = %d\n", rc);
+}
+
+static void xen_acpi_processor_resume(void)
+{
+ static DECLARE_WORK(wq, xen_acpi_processor_resume_worker);
+
+ /*
+ * xen_upload_processor_pm_data() calls non-atomic code.
+ * However, the context for xen_acpi_processor_resume is syscore
+ * with only the boot CPU online and in an atomic context.
+ *
+ * So defer the upload for some point safer.
+ */
+ schedule_work(&wq);
+}
+
+static struct syscore_ops xap_syscore_ops = {
+ .resume = xen_acpi_processor_resume,
+};
+
+static int __init xen_acpi_processor_init(void)
+{
+ int i;
+ int rc;
+
+ if (!xen_initial_domain())
+ return -ENODEV;
+
+ nr_acpi_bits = get_max_acpi_id() + 1;
+ acpi_ids_done = bitmap_zalloc(nr_acpi_bits, 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");
+ bitmap_free(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;
+
+ register_syscore_ops(&xap_syscore_ops);
+
+ 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();
+ bitmap_free(acpi_ids_done);
+ return rc;
+}
+static void __exit xen_acpi_processor_exit(void)
+{
+ int i;
+
+ unregister_syscore_ops(&xap_syscore_ops);
+ bitmap_free(acpi_ids_done);
+ bitmap_free(acpi_id_present);
+ bitmap_free(acpi_id_cst_present);
+ kfree(acpi_psd);
+ for_each_possible_cpu(i)
+ acpi_processor_unregister_performance(i);
+
+ free_acpi_perf_data();
+}
+
+MODULE_AUTHOR("Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>");
+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);