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Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c')
-rw-r--r--arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c626
1 files changed, 0 insertions, 626 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
deleted file mode 100644
index 4f6f679f279..00000000000
--- a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
+++ /dev/null
@@ -1,626 +0,0 @@
-/*
- * pcc-cpufreq.c - Processor Clocking Control firmware cpufreq interface
- *
- * Copyright (C) 2009 Red Hat, Matthew Garrett <mjg@redhat.com>
- * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
- * Nagananda Chumbalkar <nagananda.chumbalkar@hp.com>
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; version 2 of the License.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or NON
- * INFRINGEMENT. See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/smp.h>
-#include <linux/sched.h>
-#include <linux/cpufreq.h>
-#include <linux/compiler.h>
-#include <linux/slab.h>
-
-#include <linux/acpi.h>
-#include <linux/io.h>
-#include <linux/spinlock.h>
-#include <linux/uaccess.h>
-
-#include <acpi/processor.h>
-
-#define PCC_VERSION "1.00.00"
-#define POLL_LOOPS 300
-
-#define CMD_COMPLETE 0x1
-#define CMD_GET_FREQ 0x0
-#define CMD_SET_FREQ 0x1
-
-#define BUF_SZ 4
-
-#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
- "pcc-cpufreq", msg)
-
-struct pcc_register_resource {
- u8 descriptor;
- u16 length;
- u8 space_id;
- u8 bit_width;
- u8 bit_offset;
- u8 access_size;
- u64 address;
-} __attribute__ ((packed));
-
-struct pcc_memory_resource {
- u8 descriptor;
- u16 length;
- u8 space_id;
- u8 resource_usage;
- u8 type_specific;
- u64 granularity;
- u64 minimum;
- u64 maximum;
- u64 translation_offset;
- u64 address_length;
-} __attribute__ ((packed));
-
-static struct cpufreq_driver pcc_cpufreq_driver;
-
-struct pcc_header {
- u32 signature;
- u16 length;
- u8 major;
- u8 minor;
- u32 features;
- u16 command;
- u16 status;
- u32 latency;
- u32 minimum_time;
- u32 maximum_time;
- u32 nominal;
- u32 throttled_frequency;
- u32 minimum_frequency;
-};
-
-static void __iomem *pcch_virt_addr;
-static struct pcc_header __iomem *pcch_hdr;
-
-static DEFINE_SPINLOCK(pcc_lock);
-
-static struct acpi_generic_address doorbell;
-
-static u64 doorbell_preserve;
-static u64 doorbell_write;
-
-static u8 OSC_UUID[16] = {0x63, 0x9B, 0x2C, 0x9F, 0x70, 0x91, 0x49, 0x1f,
- 0xBB, 0x4F, 0xA5, 0x98, 0x2F, 0xA1, 0xB5, 0x46};
-
-struct pcc_cpu {
- u32 input_offset;
- u32 output_offset;
-};
-
-static struct pcc_cpu __percpu *pcc_cpu_info;
-
-static int pcc_cpufreq_verify(struct cpufreq_policy *policy)
-{
- cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
- policy->cpuinfo.max_freq);
- return 0;
-}
-
-static inline void pcc_cmd(void)
-{
- u64 doorbell_value;
- int i;
-
- acpi_read(&doorbell_value, &doorbell);
- acpi_write((doorbell_value & doorbell_preserve) | doorbell_write,
- &doorbell);
-
- for (i = 0; i < POLL_LOOPS; i++) {
- if (ioread16(&pcch_hdr->status) & CMD_COMPLETE)
- break;
- }
-}
-
-static inline void pcc_clear_mapping(void)
-{
- if (pcch_virt_addr)
- iounmap(pcch_virt_addr);
- pcch_virt_addr = NULL;
-}
-
-static unsigned int pcc_get_freq(unsigned int cpu)
-{
- struct pcc_cpu *pcc_cpu_data;
- unsigned int curr_freq;
- unsigned int freq_limit;
- u16 status;
- u32 input_buffer;
- u32 output_buffer;
-
- spin_lock(&pcc_lock);
-
- dprintk("get: get_freq for CPU %d\n", cpu);
- pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu);
-
- input_buffer = 0x1;
- iowrite32(input_buffer,
- (pcch_virt_addr + pcc_cpu_data->input_offset));
- iowrite16(CMD_GET_FREQ, &pcch_hdr->command);
-
- pcc_cmd();
-
- output_buffer =
- ioread32(pcch_virt_addr + pcc_cpu_data->output_offset);
-
- /* Clear the input buffer - we are done with the current command */
- memset_io((pcch_virt_addr + pcc_cpu_data->input_offset), 0, BUF_SZ);
-
- status = ioread16(&pcch_hdr->status);
- if (status != CMD_COMPLETE) {
- dprintk("get: FAILED: for CPU %d, status is %d\n",
- cpu, status);
- goto cmd_incomplete;
- }
- iowrite16(0, &pcch_hdr->status);
- curr_freq = (((ioread32(&pcch_hdr->nominal) * (output_buffer & 0xff))
- / 100) * 1000);
-
- dprintk("get: SUCCESS: (virtual) output_offset for cpu %d is "
- "0x%x, contains a value of: 0x%x. Speed is: %d MHz\n",
- cpu, (pcch_virt_addr + pcc_cpu_data->output_offset),
- output_buffer, curr_freq);
-
- freq_limit = (output_buffer >> 8) & 0xff;
- if (freq_limit != 0xff) {
- dprintk("get: frequency for cpu %d is being temporarily"
- " capped at %d\n", cpu, curr_freq);
- }
-
- spin_unlock(&pcc_lock);
- return curr_freq;
-
-cmd_incomplete:
- iowrite16(0, &pcch_hdr->status);
- spin_unlock(&pcc_lock);
- return -EINVAL;
-}
-
-static int pcc_cpufreq_target(struct cpufreq_policy *policy,
- unsigned int target_freq,
- unsigned int relation)
-{
- struct pcc_cpu *pcc_cpu_data;
- struct cpufreq_freqs freqs;
- u16 status;
- u32 input_buffer;
- int cpu;
-
- spin_lock(&pcc_lock);
- cpu = policy->cpu;
- pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu);
-
- dprintk("target: CPU %d should go to target freq: %d "
- "(virtual) input_offset is 0x%x\n",
- cpu, target_freq,
- (pcch_virt_addr + pcc_cpu_data->input_offset));
-
- freqs.new = target_freq;
- freqs.cpu = cpu;
- cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
-
- input_buffer = 0x1 | (((target_freq * 100)
- / (ioread32(&pcch_hdr->nominal) * 1000)) << 8);
- iowrite32(input_buffer,
- (pcch_virt_addr + pcc_cpu_data->input_offset));
- iowrite16(CMD_SET_FREQ, &pcch_hdr->command);
-
- pcc_cmd();
-
- /* Clear the input buffer - we are done with the current command */
- memset_io((pcch_virt_addr + pcc_cpu_data->input_offset), 0, BUF_SZ);
-
- status = ioread16(&pcch_hdr->status);
- if (status != CMD_COMPLETE) {
- dprintk("target: FAILED for cpu %d, with status: 0x%x\n",
- cpu, status);
- goto cmd_incomplete;
- }
- iowrite16(0, &pcch_hdr->status);
-
- cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
- dprintk("target: was SUCCESSFUL for cpu %d\n", cpu);
- spin_unlock(&pcc_lock);
-
- return 0;
-
-cmd_incomplete:
- iowrite16(0, &pcch_hdr->status);
- spin_unlock(&pcc_lock);
- return -EINVAL;
-}
-
-static int pcc_get_offset(int cpu)
-{
- acpi_status status;
- struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
- union acpi_object *pccp, *offset;
- struct pcc_cpu *pcc_cpu_data;
- struct acpi_processor *pr;
- int ret = 0;
-
- pr = per_cpu(processors, cpu);
- pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu);
-
- status = acpi_evaluate_object(pr->handle, "PCCP", NULL, &buffer);
- if (ACPI_FAILURE(status))
- return -ENODEV;
-
- pccp = buffer.pointer;
- if (!pccp || pccp->type != ACPI_TYPE_PACKAGE) {
- ret = -ENODEV;
- goto out_free;
- };
-
- offset = &(pccp->package.elements[0]);
- if (!offset || offset->type != ACPI_TYPE_INTEGER) {
- ret = -ENODEV;
- goto out_free;
- }
-
- pcc_cpu_data->input_offset = offset->integer.value;
-
- offset = &(pccp->package.elements[1]);
- if (!offset || offset->type != ACPI_TYPE_INTEGER) {
- ret = -ENODEV;
- goto out_free;
- }
-
- pcc_cpu_data->output_offset = offset->integer.value;
-
- memset_io((pcch_virt_addr + pcc_cpu_data->input_offset), 0, BUF_SZ);
- memset_io((pcch_virt_addr + pcc_cpu_data->output_offset), 0, BUF_SZ);
-
- dprintk("pcc_get_offset: for CPU %d: pcc_cpu_data "
- "input_offset: 0x%x, pcc_cpu_data output_offset: 0x%x\n",
- cpu, pcc_cpu_data->input_offset, pcc_cpu_data->output_offset);
-out_free:
- kfree(buffer.pointer);
- return ret;
-}
-
-static int __init pcc_cpufreq_do_osc(acpi_handle *handle)
-{
- acpi_status status;
- struct acpi_object_list input;
- struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
- union acpi_object in_params[4];
- union acpi_object *out_obj;
- u32 capabilities[2];
- u32 errors;
- u32 supported;
- int ret = 0;
-
- input.count = 4;
- input.pointer = in_params;
- input.count = 4;
- input.pointer = in_params;
- in_params[0].type = ACPI_TYPE_BUFFER;
- in_params[0].buffer.length = 16;
- in_params[0].buffer.pointer = OSC_UUID;
- in_params[1].type = ACPI_TYPE_INTEGER;
- in_params[1].integer.value = 1;
- in_params[2].type = ACPI_TYPE_INTEGER;
- in_params[2].integer.value = 2;
- in_params[3].type = ACPI_TYPE_BUFFER;
- in_params[3].buffer.length = 8;
- in_params[3].buffer.pointer = (u8 *)&capabilities;
-
- capabilities[0] = OSC_QUERY_ENABLE;
- capabilities[1] = 0x1;
-
- status = acpi_evaluate_object(*handle, "_OSC", &input, &output);
- if (ACPI_FAILURE(status))
- return -ENODEV;
-
- if (!output.length)
- return -ENODEV;
-
- out_obj = output.pointer;
- if (out_obj->type != ACPI_TYPE_BUFFER) {
- ret = -ENODEV;
- goto out_free;
- }
-
- errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
- if (errors) {
- ret = -ENODEV;
- goto out_free;
- }
-
- supported = *((u32 *)(out_obj->buffer.pointer + 4));
- if (!(supported & 0x1)) {
- ret = -ENODEV;
- goto out_free;
- }
-
- kfree(output.pointer);
- capabilities[0] = 0x0;
- capabilities[1] = 0x1;
-
- status = acpi_evaluate_object(*handle, "_OSC", &input, &output);
- if (ACPI_FAILURE(status))
- return -ENODEV;
-
- if (!output.length)
- return -ENODEV;
-
- out_obj = output.pointer;
- if (out_obj->type != ACPI_TYPE_BUFFER) {
- ret = -ENODEV;
- goto out_free;
- }
-
- errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
- if (errors) {
- ret = -ENODEV;
- goto out_free;
- }
-
- supported = *((u32 *)(out_obj->buffer.pointer + 4));
- if (!(supported & 0x1)) {
- ret = -ENODEV;
- goto out_free;
- }
-
-out_free:
- kfree(output.pointer);
- return ret;
-}
-
-static int __init pcc_cpufreq_probe(void)
-{
- acpi_status status;
- struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
- struct pcc_memory_resource *mem_resource;
- struct pcc_register_resource *reg_resource;
- union acpi_object *out_obj, *member;
- acpi_handle handle, osc_handle, pcch_handle;
- int ret = 0;
-
- status = acpi_get_handle(NULL, "\\_SB", &handle);
- if (ACPI_FAILURE(status))
- return -ENODEV;
-
- status = acpi_get_handle(handle, "PCCH", &pcch_handle);
- if (ACPI_FAILURE(status))
- return -ENODEV;
-
- status = acpi_get_handle(handle, "_OSC", &osc_handle);
- if (ACPI_SUCCESS(status)) {
- ret = pcc_cpufreq_do_osc(&osc_handle);
- if (ret)
- dprintk("probe: _OSC evaluation did not succeed\n");
- /* Firmware's use of _OSC is optional */
- ret = 0;
- }
-
- status = acpi_evaluate_object(handle, "PCCH", NULL, &output);
- if (ACPI_FAILURE(status))
- return -ENODEV;
-
- out_obj = output.pointer;
- if (out_obj->type != ACPI_TYPE_PACKAGE) {
- ret = -ENODEV;
- goto out_free;
- }
-
- member = &out_obj->package.elements[0];
- if (member->type != ACPI_TYPE_BUFFER) {
- ret = -ENODEV;
- goto out_free;
- }
-
- mem_resource = (struct pcc_memory_resource *)member->buffer.pointer;
-
- dprintk("probe: mem_resource descriptor: 0x%x,"
- " length: %d, space_id: %d, resource_usage: %d,"
- " type_specific: %d, granularity: 0x%llx,"
- " minimum: 0x%llx, maximum: 0x%llx,"
- " translation_offset: 0x%llx, address_length: 0x%llx\n",
- mem_resource->descriptor, mem_resource->length,
- mem_resource->space_id, mem_resource->resource_usage,
- mem_resource->type_specific, mem_resource->granularity,
- mem_resource->minimum, mem_resource->maximum,
- mem_resource->translation_offset,
- mem_resource->address_length);
-
- if (mem_resource->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) {
- ret = -ENODEV;
- goto out_free;
- }
-
- pcch_virt_addr = ioremap_nocache(mem_resource->minimum,
- mem_resource->address_length);
- if (pcch_virt_addr == NULL) {
- dprintk("probe: could not map shared mem region\n");
- goto out_free;
- }
- pcch_hdr = pcch_virt_addr;
-
- dprintk("probe: PCCH header (virtual) addr: 0x%p\n", pcch_hdr);
- dprintk("probe: PCCH header is at physical address: 0x%llx,"
- " signature: 0x%x, length: %d bytes, major: %d, minor: %d,"
- " supported features: 0x%x, command field: 0x%x,"
- " status field: 0x%x, nominal latency: %d us\n",
- mem_resource->minimum, ioread32(&pcch_hdr->signature),
- ioread16(&pcch_hdr->length), ioread8(&pcch_hdr->major),
- ioread8(&pcch_hdr->minor), ioread32(&pcch_hdr->features),
- ioread16(&pcch_hdr->command), ioread16(&pcch_hdr->status),
- ioread32(&pcch_hdr->latency));
-
- dprintk("probe: min time between commands: %d us,"
- " max time between commands: %d us,"
- " nominal CPU frequency: %d MHz,"
- " minimum CPU frequency: %d MHz,"
- " minimum CPU frequency without throttling: %d MHz\n",
- ioread32(&pcch_hdr->minimum_time),
- ioread32(&pcch_hdr->maximum_time),
- ioread32(&pcch_hdr->nominal),
- ioread32(&pcch_hdr->throttled_frequency),
- ioread32(&pcch_hdr->minimum_frequency));
-
- member = &out_obj->package.elements[1];
- if (member->type != ACPI_TYPE_BUFFER) {
- ret = -ENODEV;
- goto pcch_free;
- }
-
- reg_resource = (struct pcc_register_resource *)member->buffer.pointer;
-
- doorbell.space_id = reg_resource->space_id;
- doorbell.bit_width = reg_resource->bit_width;
- doorbell.bit_offset = reg_resource->bit_offset;
- doorbell.access_width = 64;
- doorbell.address = reg_resource->address;
-
- dprintk("probe: doorbell: space_id is %d, bit_width is %d, "
- "bit_offset is %d, access_width is %d, address is 0x%llx\n",
- doorbell.space_id, doorbell.bit_width, doorbell.bit_offset,
- doorbell.access_width, reg_resource->address);
-
- member = &out_obj->package.elements[2];
- if (member->type != ACPI_TYPE_INTEGER) {
- ret = -ENODEV;
- goto pcch_free;
- }
-
- doorbell_preserve = member->integer.value;
-
- member = &out_obj->package.elements[3];
- if (member->type != ACPI_TYPE_INTEGER) {
- ret = -ENODEV;
- goto pcch_free;
- }
-
- doorbell_write = member->integer.value;
-
- dprintk("probe: doorbell_preserve: 0x%llx,"
- " doorbell_write: 0x%llx\n",
- doorbell_preserve, doorbell_write);
-
- pcc_cpu_info = alloc_percpu(struct pcc_cpu);
- if (!pcc_cpu_info) {
- ret = -ENOMEM;
- goto pcch_free;
- }
-
- printk(KERN_DEBUG "pcc-cpufreq: (v%s) driver loaded with frequency"
- " limits: %d MHz, %d MHz\n", PCC_VERSION,
- ioread32(&pcch_hdr->minimum_frequency),
- ioread32(&pcch_hdr->nominal));
- kfree(output.pointer);
- return ret;
-pcch_free:
- pcc_clear_mapping();
-out_free:
- kfree(output.pointer);
- return ret;
-}
-
-static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
-{
- unsigned int cpu = policy->cpu;
- unsigned int result = 0;
-
- if (!pcch_virt_addr) {
- result = -1;
- goto out;
- }
-
- result = pcc_get_offset(cpu);
- if (result) {
- dprintk("init: PCCP evaluation failed\n");
- goto out;
- }
-
- policy->max = policy->cpuinfo.max_freq =
- ioread32(&pcch_hdr->nominal) * 1000;
- policy->min = policy->cpuinfo.min_freq =
- ioread32(&pcch_hdr->minimum_frequency) * 1000;
- policy->cur = pcc_get_freq(cpu);
-
- if (!policy->cur) {
- dprintk("init: Unable to get current CPU frequency\n");
- result = -EINVAL;
- goto out;
- }
-
- dprintk("init: policy->max is %d, policy->min is %d\n",
- policy->max, policy->min);
-out:
- return result;
-}
-
-static int pcc_cpufreq_cpu_exit(struct cpufreq_policy *policy)
-{
- return 0;
-}
-
-static struct cpufreq_driver pcc_cpufreq_driver = {
- .flags = CPUFREQ_CONST_LOOPS,
- .get = pcc_get_freq,
- .verify = pcc_cpufreq_verify,
- .target = pcc_cpufreq_target,
- .init = pcc_cpufreq_cpu_init,
- .exit = pcc_cpufreq_cpu_exit,
- .name = "pcc-cpufreq",
- .owner = THIS_MODULE,
-};
-
-static int __init pcc_cpufreq_init(void)
-{
- int ret;
-
- if (acpi_disabled)
- return 0;
-
- ret = pcc_cpufreq_probe();
- if (ret) {
- dprintk("pcc_cpufreq_init: PCCH evaluation failed\n");
- return ret;
- }
-
- ret = cpufreq_register_driver(&pcc_cpufreq_driver);
-
- return ret;
-}
-
-static void __exit pcc_cpufreq_exit(void)
-{
- cpufreq_unregister_driver(&pcc_cpufreq_driver);
-
- pcc_clear_mapping();
-
- free_percpu(pcc_cpu_info);
-}
-
-MODULE_AUTHOR("Matthew Garrett, Naga Chumbalkar");
-MODULE_VERSION(PCC_VERSION);
-MODULE_DESCRIPTION("Processor Clocking Control interface driver");
-MODULE_LICENSE("GPL");
-
-late_initcall(pcc_cpufreq_init);
-module_exit(pcc_cpufreq_exit);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-04 08:01:05 +0000