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 if (!eemi_ops) 94 return -ENXIO; 95 96 switch (pm_id) { 97 case PM_GET_API_VERSION: 98 ret = eemi_ops->get_api_version(&pm_api_version); 99 sprintf(debugfs_buf, "PM-API Version = %d.%d\n", 100 pm_api_version >> 16, pm_api_version & 0xffff); 101 break; 102 case PM_QUERY_DATA: 103 qdata.qid = pm_api_arg[0]; 104 qdata.arg1 = pm_api_arg[1]; 105 qdata.arg2 = pm_api_arg[2]; 106 qdata.arg3 = pm_api_arg[3]; 107 108 ret = eemi_ops->query_data(qdata, pm_api_ret); 109 if (ret) 110 break; 111 112 switch (qdata.qid) { 113 case PM_QID_CLOCK_GET_NAME: 114 sprintf(debugfs_buf, "Clock name = %s\n", 115 (char *)pm_api_ret); 116 break; 117 case PM_QID_CLOCK_GET_FIXEDFACTOR_PARAMS: 118 sprintf(debugfs_buf, "Multiplier = %d, Divider = %d\n", 119 pm_api_ret[1], pm_api_ret[2]); 120 break; 121 default: 122 sprintf(debugfs_buf, 123 "data[0] = 0x%08x\ndata[1] = 0x%08x\n data[2] = 0x%08x\ndata[3] = 0x%08x\n", 124 pm_api_ret[0], pm_api_ret[1], 125 pm_api_ret[2], pm_api_ret[3]); 126 } 127 break; 128 default: 129 sprintf(debugfs_buf, "Unsupported PM-API request\n"); 130 ret = -EINVAL; 131 } 132 133 return ret; 134 } 135 136 /** 137 * zynqmp_pm_debugfs_api_write() - debugfs write function 138 * @file: User file 139 * @ptr: User entered PM-API string 140 * @len: Length of the userspace buffer 141 * @off: Offset within the file 142 * 143 * Used for triggering pm api functions by writing 144 * echo <pm_api_id> > /sys/kernel/debug/zynqmp_pm/power or 145 * echo <pm_api_name> > /sys/kernel/debug/zynqmp_pm/power 146 * 147 * Return: Number of bytes copied if PM-API request succeeds, 148 * the corresponding error code otherwise 149 */ 150 static ssize_t zynqmp_pm_debugfs_api_write(struct file *file, 151 const char __user *ptr, size_t len, 152 loff_t *off) 153 { 154 char *kern_buff, *tmp_buff; 155 char *pm_api_req; 156 u32 pm_id = 0; 157 u64 pm_api_arg[4] = {0, 0, 0, 0}; 158 /* Return values from PM APIs calls */ 159 u32 pm_api_ret[4] = {0, 0, 0, 0}; 160 161 int ret; 162 int i = 0; 163 164 strcpy(debugfs_buf, ""); 165 166 if (*off != 0 || len == 0) 167 return -EINVAL; 168 169 kern_buff = kzalloc(len, GFP_KERNEL); 170 if (!kern_buff) 171 return -ENOMEM; 172 173 tmp_buff = kern_buff; 174 175 ret = strncpy_from_user(kern_buff, ptr, len); 176 if (ret < 0) { 177 ret = -EFAULT; 178 goto err; 179 } 180 181 /* Read the API name from a user request */ 182 pm_api_req = strsep(&kern_buff, " "); 183 184 ret = get_pm_api_id(pm_api_req, &pm_id); 185 if (ret < 0) 186 goto err; 187 188 /* Read node_id and arguments from the PM-API request */ 189 pm_api_req = strsep(&kern_buff, " "); 190 while ((i < ARRAY_SIZE(pm_api_arg)) && pm_api_req) { 191 pm_api_arg[i++] = zynqmp_pm_argument_value(pm_api_req); 192 pm_api_req = strsep(&kern_buff, " "); 193 } 194 195 ret = process_api_request(pm_id, pm_api_arg, pm_api_ret); 196 197 err: 198 kfree(tmp_buff); 199 if (ret) 200 return ret; 201 202 return len; 203 } 204 205 /** 206 * zynqmp_pm_debugfs_api_read() - debugfs read function 207 * @file: User file 208 * @ptr: Requested pm_api_version string 209 * @len: Length of the userspace buffer 210 * @off: Offset within the file 211 * 212 * Return: Length of the version string on success 213 * else error code 214 */ 215 static ssize_t zynqmp_pm_debugfs_api_read(struct file *file, char __user *ptr, 216 size_t len, loff_t *off) 217 { 218 return simple_read_from_buffer(ptr, len, off, debugfs_buf, 219 strlen(debugfs_buf)); 220 } 221 222 /* Setup debugfs fops */ 223 static const struct file_operations fops_zynqmp_pm_dbgfs = { 224 .owner = THIS_MODULE, 225 .write = zynqmp_pm_debugfs_api_write, 226 .read = zynqmp_pm_debugfs_api_read, 227 }; 228 229 /** 230 * zynqmp_pm_api_debugfs_init - Initialize debugfs interface 231 * 232 * Return: None 233 */ 234 void zynqmp_pm_api_debugfs_init(void) 235 { 236 /* Initialize debugfs interface */ 237 firmware_debugfs_root = debugfs_create_dir("zynqmp-firmware", NULL); 238 debugfs_create_file("pm", 0660, firmware_debugfs_root, NULL, 239 &fops_zynqmp_pm_dbgfs); 240 } 241 242 /** 243 * zynqmp_pm_api_debugfs_exit - Remove debugfs interface 244 * 245 * Return: None 246 */ 247 void zynqmp_pm_api_debugfs_exit(void) 248 { 249 debugfs_remove_recursive(firmware_debugfs_root); 250 } 251