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1// SPDX-License-Identifier: GPL-2.02/*3 * Xilinx Zynq MPSoC Firmware layer for debugfs APIs4 *5 * Copyright (C) 2014-2018 Xilinx, Inc.6 *7 * Michal Simek <michal.simek@amd.com>8 * Davorin Mista <davorin.mista@aggios.com>9 * Jolly Shah <jollys@xilinx.com>10 * Rajan Vaja <rajanv@xilinx.com>11 */12 13#include <linux/compiler.h>14#include <linux/module.h>15#include <linux/slab.h>16#include <linux/debugfs.h>17#include <linux/uaccess.h>18 19#include <linux/firmware/xlnx-zynqmp.h>20#include "zynqmp-debug.h"21 22#define PM_API_NAME_LEN 5023 24struct pm_api_info {25 u32 api_id;26 char api_name[PM_API_NAME_LEN];27 char api_name_len;28};29 30static char debugfs_buf[PAGE_SIZE];31 32#define PM_API(id) {id, #id, strlen(#id)}33static struct pm_api_info pm_api_list[] = {34 PM_API(PM_GET_API_VERSION),35 PM_API(PM_QUERY_DATA),36};37 38static struct dentry *firmware_debugfs_root;39 40/**41 * zynqmp_pm_argument_value() - Extract argument value from a PM-API request42 * @arg: Entered PM-API argument in string format43 *44 * Return: Argument value in unsigned integer format on success45 * 0 otherwise46 */47static u64 zynqmp_pm_argument_value(char *arg)48{49 u64 value;50 51 if (!arg)52 return 0;53 54 if (!kstrtou64(arg, 0, &value))55 return value;56 57 return 0;58}59 60/**61 * get_pm_api_id() - Extract API-ID from a PM-API request62 * @pm_api_req: Entered PM-API argument in string format63 * @pm_id: API-ID64 *65 * Return: 0 on success else error code66 */67static int get_pm_api_id(char *pm_api_req, u32 *pm_id)68{69 int i;70 71 for (i = 0; i < ARRAY_SIZE(pm_api_list) ; i++) {72 if (!strncasecmp(pm_api_req, pm_api_list[i].api_name,73 pm_api_list[i].api_name_len)) {74 *pm_id = pm_api_list[i].api_id;75 break;76 }77 }78 79 /* If no name was entered look for PM-API ID instead */80 if (i == ARRAY_SIZE(pm_api_list) && kstrtouint(pm_api_req, 10, pm_id))81 return -EINVAL;82 83 return 0;84}85 86static int process_api_request(u32 pm_id, u64 *pm_api_arg, u32 *pm_api_ret)87{88 u32 pm_api_version;89 int ret;90 struct zynqmp_pm_query_data qdata = {0};91 92 switch (pm_id) {93 case PM_GET_API_VERSION:94 ret = zynqmp_pm_get_api_version(&pm_api_version);95 sprintf(debugfs_buf, "PM-API Version = %d.%d\n",96 pm_api_version >> 16, pm_api_version & 0xffff);97 break;98 case PM_QUERY_DATA:99 qdata.qid = pm_api_arg[0];100 qdata.arg1 = pm_api_arg[1];101 qdata.arg2 = pm_api_arg[2];102 qdata.arg3 = pm_api_arg[3];103 104 ret = zynqmp_pm_query_data(qdata, pm_api_ret);105 if (ret)106 break;107 108 switch (qdata.qid) {109 case PM_QID_CLOCK_GET_NAME:110 sprintf(debugfs_buf, "Clock name = %s\n",111 (char *)pm_api_ret);112 break;113 case PM_QID_CLOCK_GET_FIXEDFACTOR_PARAMS:114 sprintf(debugfs_buf, "Multiplier = %d, Divider = %d\n",115 pm_api_ret[1], pm_api_ret[2]);116 break;117 default:118 sprintf(debugfs_buf,119 "data[0] = 0x%08x\ndata[1] = 0x%08x\n data[2] = 0x%08x\ndata[3] = 0x%08x\n",120 pm_api_ret[0], pm_api_ret[1],121 pm_api_ret[2], pm_api_ret[3]);122 }123 break;124 default:125 sprintf(debugfs_buf, "Unsupported PM-API request\n");126 ret = -EINVAL;127 }128 129 return ret;130}131 132/**133 * zynqmp_pm_debugfs_api_write() - debugfs write function134 * @file: User file135 * @ptr: User entered PM-API string136 * @len: Length of the userspace buffer137 * @off: Offset within the file138 *139 * Used for triggering pm api functions by writing140 * echo <pm_api_id> > /sys/kernel/debug/zynqmp_pm/power or141 * echo <pm_api_name> > /sys/kernel/debug/zynqmp_pm/power142 *143 * Return: Number of bytes copied if PM-API request succeeds,144 * the corresponding error code otherwise145 */146static ssize_t zynqmp_pm_debugfs_api_write(struct file *file,147 const char __user *ptr, size_t len,148 loff_t *off)149{150 char *kern_buff, *tmp_buff;151 char *pm_api_req;152 u32 pm_id = 0;153 u64 pm_api_arg[4] = {0, 0, 0, 0};154 /* Return values from PM APIs calls */155 u32 pm_api_ret[4] = {0, 0, 0, 0};156 157 int ret;158 int i = 0;159 160 strcpy(debugfs_buf, "");161 162 if (*off != 0 || len <= 1 || len > PAGE_SIZE - 1)163 return -EINVAL;164 165 kern_buff = memdup_user_nul(ptr, len);166 if (IS_ERR(kern_buff))167 return PTR_ERR(kern_buff);168 tmp_buff = kern_buff;169 170 /* Read the API name from a user request */171 pm_api_req = strsep(&kern_buff, " ");172 173 ret = get_pm_api_id(pm_api_req, &pm_id);174 if (ret < 0)175 goto err;176 177 /* Read node_id and arguments from the PM-API request */178 pm_api_req = strsep(&kern_buff, " ");179 while ((i < ARRAY_SIZE(pm_api_arg)) && pm_api_req) {180 pm_api_arg[i++] = zynqmp_pm_argument_value(pm_api_req);181 pm_api_req = strsep(&kern_buff, " ");182 }183 184 ret = process_api_request(pm_id, pm_api_arg, pm_api_ret);185 186err:187 kfree(tmp_buff);188 if (ret)189 return ret;190 191 return len;192}193 194/**195 * zynqmp_pm_debugfs_api_read() - debugfs read function196 * @file: User file197 * @ptr: Requested pm_api_version string198 * @len: Length of the userspace buffer199 * @off: Offset within the file200 *201 * Return: Length of the version string on success202 * else error code203 */204static ssize_t zynqmp_pm_debugfs_api_read(struct file *file, char __user *ptr,205 size_t len, loff_t *off)206{207 return simple_read_from_buffer(ptr, len, off, debugfs_buf,208 strlen(debugfs_buf));209}210 211/* Setup debugfs fops */212static const struct file_operations fops_zynqmp_pm_dbgfs = {213 .owner = THIS_MODULE,214 .write = zynqmp_pm_debugfs_api_write,215 .read = zynqmp_pm_debugfs_api_read,216};217 218/**219 * zynqmp_pm_api_debugfs_init - Initialize debugfs interface220 *221 * Return: None222 */223void zynqmp_pm_api_debugfs_init(void)224{225 /* Initialize debugfs interface */226 firmware_debugfs_root = debugfs_create_dir("zynqmp-firmware", NULL);227 debugfs_create_file("pm", 0660, firmware_debugfs_root, NULL,228 &fops_zynqmp_pm_dbgfs);229}230 231/**232 * zynqmp_pm_api_debugfs_exit - Remove debugfs interface233 *234 * Return: None235 */236void zynqmp_pm_api_debugfs_exit(void)237{238 debugfs_remove_recursive(firmware_debugfs_root);239}240