1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Xilinx Zynq MPSoC Firmware layer for debugfs APIs 4 * 5 * Copyright (C) 2014-2018 Xilinx, Inc. 6 * 7 * Michal Simek <michal.simek@xilinx.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 50 23 24 struct pm_api_info { 25 u32 api_id; 26 char api_name[PM_API_NAME_LEN]; 27 char api_name_len; 28 }; 29 30 static char debugfs_buf[PAGE_SIZE]; 31 32 #define PM_API(id) {id, #id, strlen(#id)} 33 static struct pm_api_info pm_api_list[] = { 34 PM_API(PM_GET_API_VERSION), 35 PM_API(PM_QUERY_DATA), 36 }; 37 38 struct dentry *firmware_debugfs_root; 39 40 /** 41 * zynqmp_pm_argument_value() - Extract argument value from a PM-API request 42 * @arg: Entered PM-API argument in string format 43 * 44 * Return: Argument value in unsigned integer format on success 45 * 0 otherwise 46 */ 47 static 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 request 62 * @pm_api_req: Entered PM-API argument in string format 63 * @pm_id: API-ID 64 * 65 * Return: 0 on success else error code 66 */ 67 static 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 86 static int process_api_request(u32 pm_id, u64 *pm_api_arg, u32 *pm_api_ret) 87 { 88 const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops(); 89 u32 pm_api_version; 90 int ret; 91 struct zynqmp_pm_query_data qdata = {0}; 92 93 switch (pm_id) { 94 case PM_GET_API_VERSION: 95 ret = eemi_ops->get_api_version(&pm_api_version); 96 sprintf(debugfs_buf, "PM-API Version = %d.%d\n", 97 pm_api_version >> 16, pm_api_version & 0xffff); 98 break; 99 case PM_QUERY_DATA: 100 qdata.qid = pm_api_arg[0]; 101 qdata.arg1 = pm_api_arg[1]; 102 qdata.arg2 = pm_api_arg[2]; 103 qdata.arg3 = pm_api_arg[3]; 104 105 ret = eemi_ops->query_data(qdata, pm_api_ret); 106 if (ret) 107 break; 108 109 switch (qdata.qid) { 110 case PM_QID_CLOCK_GET_NAME: 111 sprintf(debugfs_buf, "Clock name = %s\n", 112 (char *)pm_api_ret); 113 break; 114 case PM_QID_CLOCK_GET_FIXEDFACTOR_PARAMS: 115 sprintf(debugfs_buf, "Multiplier = %d, Divider = %d\n", 116 pm_api_ret[1], pm_api_ret[2]); 117 break; 118 default: 119 sprintf(debugfs_buf, 120 "data[0] = 0x%08x\ndata[1] = 0x%08x\n data[2] = 0x%08x\ndata[3] = 0x%08x\n", 121 pm_api_ret[0], pm_api_ret[1], 122 pm_api_ret[2], pm_api_ret[3]); 123 } 124 break; 125 default: 126 sprintf(debugfs_buf, "Unsupported PM-API request\n"); 127 ret = -EINVAL; 128 } 129 130 return ret; 131 } 132 133 /** 134 * zynqmp_pm_debugfs_api_write() - debugfs write function 135 * @file: User file 136 * @ptr: User entered PM-API string 137 * @len: Length of the userspace buffer 138 * @off: Offset within the file 139 * 140 * Used for triggering pm api functions by writing 141 * echo <pm_api_id> > /sys/kernel/debug/zynqmp_pm/power or 142 * echo <pm_api_name> > /sys/kernel/debug/zynqmp_pm/power 143 * 144 * Return: Number of bytes copied if PM-API request succeeds, 145 * the corresponding error code otherwise 146 */ 147 static ssize_t zynqmp_pm_debugfs_api_write(struct file *file, 148 const char __user *ptr, size_t len, 149 loff_t *off) 150 { 151 char *kern_buff, *tmp_buff; 152 char *pm_api_req; 153 u32 pm_id = 0; 154 u64 pm_api_arg[4] = {0, 0, 0, 0}; 155 /* Return values from PM APIs calls */ 156 u32 pm_api_ret[4] = {0, 0, 0, 0}; 157 158 int ret; 159 int i = 0; 160 161 strcpy(debugfs_buf, ""); 162 163 if (*off != 0 || len <= 1 || len > PAGE_SIZE - 1) 164 return -EINVAL; 165 166 kern_buff = memdup_user_nul(ptr, len); 167 if (IS_ERR(kern_buff)) 168 return PTR_ERR(kern_buff); 169 tmp_buff = kern_buff; 170 171 /* Read the API name from a user request */ 172 pm_api_req = strsep(&kern_buff, " "); 173 174 ret = get_pm_api_id(pm_api_req, &pm_id); 175 if (ret < 0) 176 goto err; 177 178 /* Read node_id and arguments from the PM-API request */ 179 pm_api_req = strsep(&kern_buff, " "); 180 while ((i < ARRAY_SIZE(pm_api_arg)) && pm_api_req) { 181 pm_api_arg[i++] = zynqmp_pm_argument_value(pm_api_req); 182 pm_api_req = strsep(&kern_buff, " "); 183 } 184 185 ret = process_api_request(pm_id, pm_api_arg, pm_api_ret); 186 187 err: 188 kfree(tmp_buff); 189 if (ret) 190 return ret; 191 192 return len; 193 } 194 195 /** 196 * zynqmp_pm_debugfs_api_read() - debugfs read function 197 * @file: User file 198 * @ptr: Requested pm_api_version string 199 * @len: Length of the userspace buffer 200 * @off: Offset within the file 201 * 202 * Return: Length of the version string on success 203 * else error code 204 */ 205 static ssize_t zynqmp_pm_debugfs_api_read(struct file *file, char __user *ptr, 206 size_t len, loff_t *off) 207 { 208 return simple_read_from_buffer(ptr, len, off, debugfs_buf, 209 strlen(debugfs_buf)); 210 } 211 212 /* Setup debugfs fops */ 213 static const struct file_operations fops_zynqmp_pm_dbgfs = { 214 .owner = THIS_MODULE, 215 .write = zynqmp_pm_debugfs_api_write, 216 .read = zynqmp_pm_debugfs_api_read, 217 }; 218 219 /** 220 * zynqmp_pm_api_debugfs_init - Initialize debugfs interface 221 * 222 * Return: None 223 */ 224 void zynqmp_pm_api_debugfs_init(void) 225 { 226 /* Initialize debugfs interface */ 227 firmware_debugfs_root = debugfs_create_dir("zynqmp-firmware", NULL); 228 debugfs_create_file("pm", 0660, firmware_debugfs_root, NULL, 229 &fops_zynqmp_pm_dbgfs); 230 } 231 232 /** 233 * zynqmp_pm_api_debugfs_exit - Remove debugfs interface 234 * 235 * Return: None 236 */ 237 void zynqmp_pm_api_debugfs_exit(void) 238 { 239 debugfs_remove_recursive(firmware_debugfs_root); 240 } 241