pfr_telemetry.c
// SPDX-License-Identifier: GPL-2.0
/*
* ACPI Platform Firmware Runtime Telemetry driver
*
* Copyright (C) 2021 Intel Corporation
* Author: Chen Yu <yu.c.chen@intel.com>
*
* This driver allows user space to fetch telemetry data from the
* firmware with the help of the Platform Firmware Runtime Telemetry
* interface.
*/
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/platform_device.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/uio.h>
#include <linux/uuid.h>
#include <uapi/linux/pfrut.h>
#define PFRT_LOG_EXEC_IDX 0
#define PFRT_LOG_HISTORY_IDX 1
#define PFRT_LOG_ERR 0
#define PFRT_LOG_WARN 1
#define PFRT_LOG_INFO 2
#define PFRT_LOG_VERB 4
#define PFRT_FUNC_SET_LEV 1
#define PFRT_FUNC_GET_LEV 2
#define PFRT_FUNC_GET_DATA 3
#define PFRT_REVID_1 1
#define PFRT_REVID_2 2
#define PFRT_DEFAULT_REV_ID PFRT_REVID_1
enum log_index {
LOG_STATUS_IDX = 0,
LOG_EXT_STATUS_IDX = 1,
LOG_MAX_SZ_IDX = 2,
LOG_CHUNK1_LO_IDX = 3,
LOG_CHUNK1_HI_IDX = 4,
LOG_CHUNK1_SZ_IDX = 5,
LOG_CHUNK2_LO_IDX = 6,
LOG_CHUNK2_HI_IDX = 7,
LOG_CHUNK2_SZ_IDX = 8,
LOG_ROLLOVER_CNT_IDX = 9,
LOG_RESET_CNT_IDX = 10,
LOG_NR_IDX
};
struct pfrt_log_device {
int index;
struct pfrt_log_info info;
struct device *parent_dev;
struct miscdevice miscdev;
};
/* pfrt_guid is the parameter for _DSM method */
static const guid_t pfrt_log_guid =
GUID_INIT(0x75191659, 0x8178, 0x4D9D, 0xB8, 0x8F, 0xAC, 0x5E,
0x5E, 0x93, 0xE8, 0xBF);
static DEFINE_IDA(pfrt_log_ida);
static inline struct pfrt_log_device *to_pfrt_log_dev(struct file *file)
{
return container_of(file->private_data, struct pfrt_log_device, miscdev);
}
static int get_pfrt_log_data_info(struct pfrt_log_data_info *data_info,
struct pfrt_log_device *pfrt_log_dev)
{
acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
union acpi_object *out_obj, in_obj, in_buf;
int ret = -EBUSY;
memset(data_info, 0, sizeof(*data_info));
memset(&in_obj, 0, sizeof(in_obj));
memset(&in_buf, 0, sizeof(in_buf));
in_obj.type = ACPI_TYPE_PACKAGE;
in_obj.package.count = 1;
in_obj.package.elements = &in_buf;
in_buf.type = ACPI_TYPE_INTEGER;
in_buf.integer.value = pfrt_log_dev->info.log_type;
out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
pfrt_log_dev->info.log_revid, PFRT_FUNC_GET_DATA,
&in_obj, ACPI_TYPE_PACKAGE);
if (!out_obj)
return -EINVAL;
if (out_obj->package.count < LOG_NR_IDX ||
out_obj->package.elements[LOG_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_EXT_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_MAX_SZ_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_CHUNK1_LO_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_CHUNK1_HI_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_CHUNK1_SZ_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_CHUNK2_LO_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_CHUNK2_HI_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_CHUNK2_SZ_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_ROLLOVER_CNT_IDX].type != ACPI_TYPE_INTEGER ||
out_obj->package.elements[LOG_RESET_CNT_IDX].type != ACPI_TYPE_INTEGER)
goto free_acpi_buffer;
data_info->status = out_obj->package.elements[LOG_STATUS_IDX].integer.value;
data_info->ext_status =
out_obj->package.elements[LOG_EXT_STATUS_IDX].integer.value;
if (data_info->status != DSM_SUCCEED) {
dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", data_info->status);
dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n",
data_info->ext_status);
goto free_acpi_buffer;
}
data_info->max_data_size =
out_obj->package.elements[LOG_MAX_SZ_IDX].integer.value;
data_info->chunk1_addr_lo =
out_obj->package.elements[LOG_CHUNK1_LO_IDX].integer.value;
data_info->chunk1_addr_hi =
out_obj->package.elements[LOG_CHUNK1_HI_IDX].integer.value;
data_info->chunk1_size =
out_obj->package.elements[LOG_CHUNK1_SZ_IDX].integer.value;
data_info->chunk2_addr_lo =
out_obj->package.elements[LOG_CHUNK2_LO_IDX].integer.value;
data_info->chunk2_addr_hi =
out_obj->package.elements[LOG_CHUNK2_HI_IDX].integer.value;
data_info->chunk2_size =
out_obj->package.elements[LOG_CHUNK2_SZ_IDX].integer.value;
data_info->rollover_cnt =
out_obj->package.elements[LOG_ROLLOVER_CNT_IDX].integer.value;
data_info->reset_cnt =
out_obj->package.elements[LOG_RESET_CNT_IDX].integer.value;
ret = 0;
free_acpi_buffer:
kfree(out_obj);
return ret;
}
static int set_pfrt_log_level(int level, struct pfrt_log_device *pfrt_log_dev)
{
acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
union acpi_object *out_obj, *obj, in_obj, in_buf;
enum pfru_dsm_status status, ext_status;
int ret = 0;
memset(&in_obj, 0, sizeof(in_obj));
memset(&in_buf, 0, sizeof(in_buf));
in_obj.type = ACPI_TYPE_PACKAGE;
in_obj.package.count = 1;
in_obj.package.elements = &in_buf;
in_buf.type = ACPI_TYPE_INTEGER;
in_buf.integer.value = level;
out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
pfrt_log_dev->info.log_revid, PFRT_FUNC_SET_LEV,
&in_obj, ACPI_TYPE_PACKAGE);
if (!out_obj)
return -EINVAL;
obj = &out_obj->package.elements[0];
status = obj->integer.value;
if (status != DSM_SUCCEED) {
obj = &out_obj->package.elements[1];
ext_status = obj->integer.value;
dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", status);
dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n", ext_status);
ret = -EBUSY;
}
kfree(out_obj);
return ret;
}
static int get_pfrt_log_level(struct pfrt_log_device *pfrt_log_dev)
{
acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
union acpi_object *out_obj, *obj;
enum pfru_dsm_status status, ext_status;
int ret = -EBUSY;
out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
pfrt_log_dev->info.log_revid, PFRT_FUNC_GET_LEV,
NULL, ACPI_TYPE_PACKAGE);
if (!out_obj)
return -EINVAL;
obj = &out_obj->package.elements[0];
if (obj->type != ACPI_TYPE_INTEGER)
goto free_acpi_buffer;
status = obj->integer.value;
if (status != DSM_SUCCEED) {
obj = &out_obj->package.elements[1];
ext_status = obj->integer.value;
dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", status);
dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n", ext_status);
goto free_acpi_buffer;
}
obj = &out_obj->package.elements[2];
if (obj->type != ACPI_TYPE_INTEGER)
goto free_acpi_buffer;
ret = obj->integer.value;
free_acpi_buffer:
kfree(out_obj);
return ret;
}
static int valid_log_level(u32 level)
{
return level == PFRT_LOG_ERR || level == PFRT_LOG_WARN ||
level == PFRT_LOG_INFO || level == PFRT_LOG_VERB;
}
static int valid_log_type(u32 type)
{
return type == PFRT_LOG_EXEC_IDX || type == PFRT_LOG_HISTORY_IDX;
}
static inline int valid_log_revid(u32 id)
{
return id == PFRT_REVID_1 || id == PFRT_REVID_2;
}
static long pfrt_log_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct pfrt_log_device *pfrt_log_dev = to_pfrt_log_dev(file);
struct pfrt_log_data_info data_info;
struct pfrt_log_info info;
void __user *p;
int ret = 0;
p = (void __user *)arg;
switch (cmd) {
case PFRT_LOG_IOC_SET_INFO:
if (copy_from_user(&info, p, sizeof(info)))
return -EFAULT;
if (valid_log_revid(info.log_revid))
pfrt_log_dev->info.log_revid = info.log_revid;
if (valid_log_level(info.log_level)) {
ret = set_pfrt_log_level(info.log_level, pfrt_log_dev);
if (ret < 0)
return ret;
pfrt_log_dev->info.log_level = info.log_level;
}
if (valid_log_type(info.log_type))
pfrt_log_dev->info.log_type = info.log_type;
return 0;
case PFRT_LOG_IOC_GET_INFO:
info.log_level = get_pfrt_log_level(pfrt_log_dev);
if (ret < 0)
return ret;
info.log_type = pfrt_log_dev->info.log_type;
info.log_revid = pfrt_log_dev->info.log_revid;
if (copy_to_user(p, &info, sizeof(info)))
return -EFAULT;
return 0;
case PFRT_LOG_IOC_GET_DATA_INFO:
ret = get_pfrt_log_data_info(&data_info, pfrt_log_dev);
if (ret)
return ret;
if (copy_to_user(p, &data_info, sizeof(struct pfrt_log_data_info)))
return -EFAULT;
return 0;
default:
return -ENOTTY;
}
}
static int
pfrt_log_mmap(struct file *file, struct vm_area_struct *vma)
{
struct pfrt_log_device *pfrt_log_dev;
struct pfrt_log_data_info info;
unsigned long psize, vsize;
phys_addr_t base_addr;
int ret;
if (vma->vm_flags & VM_WRITE)
return -EROFS;
/* changing from read to write with mprotect is not allowed */
vma->vm_flags &= ~VM_MAYWRITE;
pfrt_log_dev = to_pfrt_log_dev(file);
ret = get_pfrt_log_data_info(&info, pfrt_log_dev);
if (ret)
return ret;
base_addr = (phys_addr_t)((info.chunk2_addr_hi << 32) | info.chunk2_addr_lo);
/* pfrt update has not been launched yet */
if (!base_addr)
return -ENODEV;
psize = info.max_data_size;
/* base address and total buffer size must be page aligned */
if (!PAGE_ALIGNED(base_addr) || !PAGE_ALIGNED(psize))
return -ENODEV;
vsize = vma->vm_end - vma->vm_start;
if (vsize > psize)
return -EINVAL;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
if (io_remap_pfn_range(vma, vma->vm_start, PFN_DOWN(base_addr),
vsize, vma->vm_page_prot))
return -EAGAIN;
return 0;
}
static const struct file_operations acpi_pfrt_log_fops = {
.owner = THIS_MODULE,
.mmap = pfrt_log_mmap,
.unlocked_ioctl = pfrt_log_ioctl,
.llseek = noop_llseek,
};
static int acpi_pfrt_log_remove(struct platform_device *pdev)
{
struct pfrt_log_device *pfrt_log_dev = platform_get_drvdata(pdev);
misc_deregister(&pfrt_log_dev->miscdev);
return 0;
}
static void pfrt_log_put_idx(void *data)
{
struct pfrt_log_device *pfrt_log_dev = data;
ida_free(&pfrt_log_ida, pfrt_log_dev->index);
}
static int acpi_pfrt_log_probe(struct platform_device *pdev)
{
acpi_handle handle = ACPI_HANDLE(&pdev->dev);
struct pfrt_log_device *pfrt_log_dev;
int ret;
if (!acpi_has_method(handle, "_DSM")) {
dev_dbg(&pdev->dev, "Missing _DSM\n");
return -ENODEV;
}
pfrt_log_dev = devm_kzalloc(&pdev->dev, sizeof(*pfrt_log_dev), GFP_KERNEL);
if (!pfrt_log_dev)
return -ENOMEM;
ret = ida_alloc(&pfrt_log_ida, GFP_KERNEL);
if (ret < 0)
return ret;
pfrt_log_dev->index = ret;
ret = devm_add_action_or_reset(&pdev->dev, pfrt_log_put_idx, pfrt_log_dev);
if (ret)
return ret;
pfrt_log_dev->info.log_revid = PFRT_DEFAULT_REV_ID;
pfrt_log_dev->parent_dev = &pdev->dev;
pfrt_log_dev->miscdev.minor = MISC_DYNAMIC_MINOR;
pfrt_log_dev->miscdev.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
"pfrt%d",
pfrt_log_dev->index);
if (!pfrt_log_dev->miscdev.name)
return -ENOMEM;
pfrt_log_dev->miscdev.nodename = devm_kasprintf(&pdev->dev, GFP_KERNEL,
"acpi_pfr_telemetry%d",
pfrt_log_dev->index);
if (!pfrt_log_dev->miscdev.nodename)
return -ENOMEM;
pfrt_log_dev->miscdev.fops = &acpi_pfrt_log_fops;
pfrt_log_dev->miscdev.parent = &pdev->dev;
ret = misc_register(&pfrt_log_dev->miscdev);
if (ret)
return ret;
platform_set_drvdata(pdev, pfrt_log_dev);
return 0;
}
static const struct acpi_device_id acpi_pfrt_log_ids[] = {
{"INTC1081"},
{}
};
MODULE_DEVICE_TABLE(acpi, acpi_pfrt_log_ids);
static struct platform_driver acpi_pfrt_log_driver = {
.driver = {
.name = "pfr_telemetry",
.acpi_match_table = acpi_pfrt_log_ids,
},
.probe = acpi_pfrt_log_probe,
.remove = acpi_pfrt_log_remove,
};
module_platform_driver(acpi_pfrt_log_driver);
MODULE_DESCRIPTION("Platform Firmware Runtime Update Telemetry driver");
MODULE_LICENSE("GPL v2");