Rajan Vaja | b321725 | 2018-09-12 12:38:39 -0700 | [diff] [blame] | 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), |
Rajan Vaja | e60f02d | 2018-09-12 12:38:40 -0700 | [diff] [blame] | 35 | PM_API(PM_QUERY_DATA), |
Rajan Vaja | b321725 | 2018-09-12 12:38:39 -0700 | [diff] [blame] | 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; |
Rajan Vaja | e60f02d | 2018-09-12 12:38:40 -0700 | [diff] [blame] | 91 | struct zynqmp_pm_query_data qdata = {0}; |
Rajan Vaja | b321725 | 2018-09-12 12:38:39 -0700 | [diff] [blame] | 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; |
Rajan Vaja | e60f02d | 2018-09-12 12:38:40 -0700 | [diff] [blame] | 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; |
Rajan Vaja | b321725 | 2018-09-12 12:38:39 -0700 | [diff] [blame] | 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 | } |