OpenCloudOS-Kernel/drivers/cpufreq/pcc-cpufreq.c

633 lines
16 KiB
C
Raw Normal View History

/*
* 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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#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 "1.10.00"
#define POLL_LOOPS 300
#define CMD_COMPLETE 0x1
#define CMD_GET_FREQ 0x0
#define CMD_SET_FREQ 0x1
#define BUF_SZ 4
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] = {0x9F, 0x2C, 0x9B, 0x63, 0x91, 0x70, 0x1f, 0x49,
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;
cpufreq: Avoid creating excessively large stack frames In the process of modifying a cpufreq policy, the cpufreq core makes a copy of it including all of the internals which is stored on the CPU stack. Because struct cpufreq_policy is relatively large, this may cause the size of the stack frame to exceed the 2 KB limit and so the GCC complains when -Wframe-larger-than= is used. In fact, it is not necessary to copy the entire policy structure in order to modify it, however. First, because cpufreq_set_policy() obtains the min and max policy limits from frequency QoS now, it is not necessary to pass the limits to it from the callers. The only things that need to be passed to it from there are the new governor pointer or (if there is a built-in governor in the driver) the "policy" value representing the governor choice. They both can be passed as individual arguments, though, so make cpufreq_set_policy() take them this way and rework its callers accordingly. This avoids making copies of cpufreq policies in the callers of cpufreq_set_policy(). Second, cpufreq_set_policy() still needs to pass the new policy data to the ->verify() callback of the cpufreq driver whose task is to sanitize the min and max policy limits. It still does not need to make a full copy of struct cpufreq_policy for this purpose, but it needs to pass a few items from it to the driver in case they are needed (different drivers have different needs in that respect and all of them have to be covered). For this reason, introduce struct cpufreq_policy_data to hold copies of the members of struct cpufreq_policy used by the existing ->verify() driver callbacks and pass a pointer to a temporary structure of that type to ->verify() (instead of passing a pointer to full struct cpufreq_policy to it). While at it, notice that intel_pstate and longrun don't really need to verify the "policy" value in struct cpufreq_policy, so drop those check from them to avoid copying "policy" into struct cpufreq_policy_data (which allows it to be slightly smaller). Also while at it fix up white space in a couple of places and make cpufreq_set_policy() static (as it can be so). Fixes: 3000ce3c52f8 ("cpufreq: Use per-policy frequency QoS") Link: https://lore.kernel.org/linux-pm/CAMuHMdX6-jb1W8uC2_237m8ctCpsnGp=JCxqt8pCWVqNXHmkVg@mail.gmail.com Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: 5.4+ <stable@vger.kernel.org> # 5.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-01-27 06:40:11 +08:00
static int pcc_cpufreq_verify(struct cpufreq_policy_data *policy)
{
cpufreq_verify_within_cpu_limits(policy);
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);
pr_debug("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) {
pr_debug("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);
pr_debug("get: SUCCESS: (virtual) output_offset for cpu %d is "
"0x%p, 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) {
pr_debug("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 0;
}
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;
cpu = policy->cpu;
pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu);
pr_debug("target: CPU %d should go to target freq: %d "
"(virtual) input_offset is 0x%p\n",
cpu, target_freq,
(pcch_virt_addr + pcc_cpu_data->input_offset));
freqs.old = policy->cur;
freqs.new = target_freq;
cpufreq_freq_transition_begin(policy, &freqs);
cpufreq: pcc-cpufreq: Fix wait_event() under spinlock Fix the following bug introduced by commit 8fec051eea73 (cpufreq: Convert existing drivers to use cpufreq_freq_transition_{begin|end}) that forgot to move the spin_lock() in pcc_cpufreq_target() past cpufreq_freq_transition_begin() which calls wait_event(): BUG: sleeping function called from invalid context at drivers/cpufreq/cpufreq.c:370 in_atomic(): 1, irqs_disabled(): 0, pid: 2636, name: modprobe Preemption disabled at:[<ffffffffa04d74d7>] pcc_cpufreq_target+0x27/0x200 [pcc_cpufreq] [ 51.025044] CPU: 57 PID: 2636 Comm: modprobe Tainted: G E 3.17.0-default #7 Hardware name: Hewlett-Packard ProLiant DL980 G7, BIOS P66 07/07/2010 00000000ffffffff ffff88026c46b828 ffffffff81589dbd 0000000000000000 ffff880037978090 ffff88026c46b848 ffffffff8108e1df ffff880037978090 0000000000000000 ffff88026c46b878 ffffffff8108e298 ffff88026d73ec00 Call Trace: [<ffffffff81589dbd>] dump_stack+0x4d/0x90 [<ffffffff8108e1df>] ___might_sleep+0x10f/0x180 [<ffffffff8108e298>] __might_sleep+0x48/0xd0 [<ffffffff8145b905>] cpufreq_freq_transition_begin+0x75/0x140 drivers/cpufreq/cpufreq.c:370 wait_event(policy->transition_wait, !policy->transition_ongoing); [<ffffffff8108fc99>] ? preempt_count_add+0xb9/0xc0 [<ffffffffa04d7513>] pcc_cpufreq_target+0x63/0x200 [pcc_cpufreq] drivers/cpufreq/pcc-cpufreq.c:207 spin_lock(&pcc_lock); [<ffffffff810e0d0f>] ? update_ts_time_stats+0x7f/0xb0 [<ffffffff8145be55>] __cpufreq_driver_target+0x85/0x170 [<ffffffff8145e4c8>] od_check_cpu+0xa8/0xb0 [<ffffffff8145ef10>] dbs_check_cpu+0x180/0x1d0 [<ffffffff8145f310>] cpufreq_governor_dbs+0x3b0/0x720 [<ffffffff8145ebe3>] od_cpufreq_governor_dbs+0x33/0xe0 [<ffffffff814593d9>] __cpufreq_governor+0xa9/0x210 [<ffffffff81459fb2>] cpufreq_set_policy+0x1e2/0x2e0 [<ffffffff8145a6cc>] cpufreq_init_policy+0x8c/0x110 [<ffffffff8145c9a0>] ? cpufreq_update_policy+0x1b0/0x1b0 [<ffffffff8108fb99>] ? preempt_count_sub+0xb9/0x100 [<ffffffff8145c6c6>] __cpufreq_add_dev+0x596/0x6b0 [<ffffffffa016c608>] ? pcc_cpufreq_probe+0x4b4/0x4b4 [pcc_cpufreq] [<ffffffff8145c7ee>] cpufreq_add_dev+0xe/0x10 [<ffffffff81408e81>] subsys_interface_register+0xc1/0xf0 [<ffffffff8108fb99>] ? preempt_count_sub+0xb9/0x100 [<ffffffff8145b3d7>] cpufreq_register_driver+0x117/0x2a0 [<ffffffffa016c65d>] pcc_cpufreq_init+0x55/0x9f8 [pcc_cpufreq] [<ffffffffa016c608>] ? pcc_cpufreq_probe+0x4b4/0x4b4 [pcc_cpufreq] [<ffffffff81000298>] do_one_initcall+0xc8/0x1f0 [<ffffffff811a731d>] ? __vunmap+0x9d/0x100 [<ffffffff810eb9a0>] do_init_module+0x30/0x1b0 [<ffffffff810edfa6>] load_module+0x686/0x710 [<ffffffff810ebb20>] ? do_init_module+0x1b0/0x1b0 [<ffffffff810ee1db>] SyS_init_module+0x9b/0xc0 [<ffffffff8158f7a9>] system_call_fastpath+0x16/0x1b Fixes: 8fec051eea73 (cpufreq: Convert existing drivers to use cpufreq_freq_transition_{begin|end}) Reported-and-tested-by: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: 3.15+ <stable@vger.kernel.org> # 3.15+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-28 03:56:08 +08:00
spin_lock(&pcc_lock);
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);
iowrite16(0, &pcch_hdr->status);
cpufreq_freq_transition_end(policy, &freqs, status != CMD_COMPLETE);
spin_unlock(&pcc_lock);
if (status != CMD_COMPLETE) {
pr_debug("target: FAILED for cpu %d, with status: 0x%x\n",
cpu, status);
return -EINVAL;
}
pr_debug("target: was SUCCESSFUL for cpu %d\n", cpu);
return 0;
}
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);
if (!pr)
return -ENODEV;
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);
pr_debug("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;
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;
int ret = 0;
status = acpi_get_handle(NULL, "\\_SB", &handle);
if (ACPI_FAILURE(status))
return -ENODEV;
if (!acpi_has_method(handle, "PCCH"))
return -ENODEV;
status = acpi_get_handle(handle, "_OSC", &osc_handle);
if (ACPI_SUCCESS(status)) {
ret = pcc_cpufreq_do_osc(&osc_handle);
if (ret)
pr_debug("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;
pr_debug("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(mem_resource->minimum,
mem_resource->address_length);
if (pcch_virt_addr == NULL) {
pr_debug("probe: could not map shared mem region\n");
ret = -ENOMEM;
goto out_free;
}
pcch_hdr = pcch_virt_addr;
pr_debug("probe: PCCH header (virtual) addr: 0x%p\n", pcch_hdr);
pr_debug("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));
pr_debug("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 = 4;
doorbell.address = reg_resource->address;
pr_debug("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;
pr_debug("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) {
pr_debug("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;
pr_debug("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",
};
static int __init pcc_cpufreq_init(void)
{
int ret;
/* Skip initialization if another cpufreq driver is there. */
if (cpufreq_get_current_driver())
return -EEXIST;
if (acpi_disabled)
return -ENODEV;
ret = pcc_cpufreq_probe();
if (ret) {
pr_debug("pcc_cpufreq_init: PCCH evaluation failed\n");
return ret;
}
if (num_present_cpus() > 4) {
pcc_cpufreq_driver.flags |= CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING;
pr_err("%s: Too many CPUs, dynamic performance scaling disabled\n",
__func__);
pr_err("%s: Try to enable another scaling driver through BIOS settings\n",
__func__);
pr_err("%s: and complain to the system vendor\n", __func__);
}
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);
}
static const struct acpi_device_id processor_device_ids[] = {
{ACPI_PROCESSOR_OBJECT_HID, },
{ACPI_PROCESSOR_DEVICE_HID, },
{},
};
MODULE_DEVICE_TABLE(acpi, processor_device_ids);
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);