swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: dc4060a5dc2557e6b5aa813bf5b73677299d62d2 authored by Linus Torvalds on 14 April 2019, 22:17:41 UTC
Linux 5.1-rc5
Linux 5.1-rc5
Tip revision: dc4060a
zynqmp-debug.c
// SPDX-License-Identifier: GPL-2.0
/*
* Xilinx Zynq MPSoC Firmware layer for debugfs APIs
*
* Copyright (C) 2014-2018 Xilinx, Inc.
*
* Michal Simek <michal.simek@xilinx.com>
* Davorin Mista <davorin.mista@aggios.com>
* Jolly Shah <jollys@xilinx.com>
* Rajan Vaja <rajanv@xilinx.com>
*/
#include <linux/compiler.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/firmware/xlnx-zynqmp.h>
#include "zynqmp-debug.h"
#define PM_API_NAME_LEN 50
struct pm_api_info {
u32 api_id;
char api_name[PM_API_NAME_LEN];
char api_name_len;
};
static char debugfs_buf[PAGE_SIZE];
#define PM_API(id) {id, #id, strlen(#id)}
static struct pm_api_info pm_api_list[] = {
PM_API(PM_GET_API_VERSION),
PM_API(PM_QUERY_DATA),
};
struct dentry *firmware_debugfs_root;
/**
* zynqmp_pm_argument_value() - Extract argument value from a PM-API request
* @arg: Entered PM-API argument in string format
*
* Return: Argument value in unsigned integer format on success
* 0 otherwise
*/
static u64 zynqmp_pm_argument_value(char *arg)
{
u64 value;
if (!arg)
return 0;
if (!kstrtou64(arg, 0, &value))
return value;
return 0;
}
/**
* get_pm_api_id() - Extract API-ID from a PM-API request
* @pm_api_req: Entered PM-API argument in string format
* @pm_id: API-ID
*
* Return: 0 on success else error code
*/
static int get_pm_api_id(char *pm_api_req, u32 *pm_id)
{
int i;
for (i = 0; i < ARRAY_SIZE(pm_api_list) ; i++) {
if (!strncasecmp(pm_api_req, pm_api_list[i].api_name,
pm_api_list[i].api_name_len)) {
*pm_id = pm_api_list[i].api_id;
break;
}
}
/* If no name was entered look for PM-API ID instead */
if (i == ARRAY_SIZE(pm_api_list) && kstrtouint(pm_api_req, 10, pm_id))
return -EINVAL;
return 0;
}
static int process_api_request(u32 pm_id, u64 *pm_api_arg, u32 *pm_api_ret)
{
const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
u32 pm_api_version;
int ret;
struct zynqmp_pm_query_data qdata = {0};
if (!eemi_ops)
return -ENXIO;
switch (pm_id) {
case PM_GET_API_VERSION:
ret = eemi_ops->get_api_version(&pm_api_version);
sprintf(debugfs_buf, "PM-API Version = %d.%d\n",
pm_api_version >> 16, pm_api_version & 0xffff);
break;
case PM_QUERY_DATA:
qdata.qid = pm_api_arg[0];
qdata.arg1 = pm_api_arg[1];
qdata.arg2 = pm_api_arg[2];
qdata.arg3 = pm_api_arg[3];
ret = eemi_ops->query_data(qdata, pm_api_ret);
if (ret)
break;
switch (qdata.qid) {
case PM_QID_CLOCK_GET_NAME:
sprintf(debugfs_buf, "Clock name = %s\n",
(char *)pm_api_ret);
break;
case PM_QID_CLOCK_GET_FIXEDFACTOR_PARAMS:
sprintf(debugfs_buf, "Multiplier = %d, Divider = %d\n",
pm_api_ret[1], pm_api_ret[2]);
break;
default:
sprintf(debugfs_buf,
"data[0] = 0x%08x\ndata[1] = 0x%08x\n data[2] = 0x%08x\ndata[3] = 0x%08x\n",
pm_api_ret[0], pm_api_ret[1],
pm_api_ret[2], pm_api_ret[3]);
}
break;
default:
sprintf(debugfs_buf, "Unsupported PM-API request\n");
ret = -EINVAL;
}
return ret;
}
/**
* zynqmp_pm_debugfs_api_write() - debugfs write function
* @file: User file
* @ptr: User entered PM-API string
* @len: Length of the userspace buffer
* @off: Offset within the file
*
* Used for triggering pm api functions by writing
* echo <pm_api_id> > /sys/kernel/debug/zynqmp_pm/power or
* echo <pm_api_name> > /sys/kernel/debug/zynqmp_pm/power
*
* Return: Number of bytes copied if PM-API request succeeds,
* the corresponding error code otherwise
*/
static ssize_t zynqmp_pm_debugfs_api_write(struct file *file,
const char __user *ptr, size_t len,
loff_t *off)
{
char *kern_buff, *tmp_buff;
char *pm_api_req;
u32 pm_id = 0;
u64 pm_api_arg[4] = {0, 0, 0, 0};
/* Return values from PM APIs calls */
u32 pm_api_ret[4] = {0, 0, 0, 0};
int ret;
int i = 0;
strcpy(debugfs_buf, "");
if (*off != 0 || len == 0)
return -EINVAL;
kern_buff = kzalloc(len, GFP_KERNEL);
if (!kern_buff)
return -ENOMEM;
tmp_buff = kern_buff;
ret = strncpy_from_user(kern_buff, ptr, len);
if (ret < 0) {
ret = -EFAULT;
goto err;
}
/* Read the API name from a user request */
pm_api_req = strsep(&kern_buff, " ");
ret = get_pm_api_id(pm_api_req, &pm_id);
if (ret < 0)
goto err;
/* Read node_id and arguments from the PM-API request */
pm_api_req = strsep(&kern_buff, " ");
while ((i < ARRAY_SIZE(pm_api_arg)) && pm_api_req) {
pm_api_arg[i++] = zynqmp_pm_argument_value(pm_api_req);
pm_api_req = strsep(&kern_buff, " ");
}
ret = process_api_request(pm_id, pm_api_arg, pm_api_ret);
err:
kfree(tmp_buff);
if (ret)
return ret;
return len;
}
/**
* zynqmp_pm_debugfs_api_read() - debugfs read function
* @file: User file
* @ptr: Requested pm_api_version string
* @len: Length of the userspace buffer
* @off: Offset within the file
*
* Return: Length of the version string on success
* else error code
*/
static ssize_t zynqmp_pm_debugfs_api_read(struct file *file, char __user *ptr,
size_t len, loff_t *off)
{
return simple_read_from_buffer(ptr, len, off, debugfs_buf,
strlen(debugfs_buf));
}
/* Setup debugfs fops */
static const struct file_operations fops_zynqmp_pm_dbgfs = {
.owner = THIS_MODULE,
.write = zynqmp_pm_debugfs_api_write,
.read = zynqmp_pm_debugfs_api_read,
};
/**
* zynqmp_pm_api_debugfs_init - Initialize debugfs interface
*
* Return: None
*/
void zynqmp_pm_api_debugfs_init(void)
{
/* Initialize debugfs interface */
firmware_debugfs_root = debugfs_create_dir("zynqmp-firmware", NULL);
debugfs_create_file("pm", 0660, firmware_debugfs_root, NULL,
&fops_zynqmp_pm_dbgfs);
}
/**
* zynqmp_pm_api_debugfs_exit - Remove debugfs interface
*
* Return: None
*/
void zynqmp_pm_api_debugfs_exit(void)
{
debugfs_remove_recursive(firmware_debugfs_root);
}