1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Amlogic Secure Monitor driver 4 * 5 * Copyright (C) 2016 Endless Mobile, Inc. 6 * Author: Carlo Caione <carlo@endlessm.com> 7 */ 8 9 #define pr_fmt(fmt) "meson-sm: " fmt 10 11 #include <linux/arm-smccc.h> 12 #include <linux/bug.h> 13 #include <linux/io.h> 14 #include <linux/module.h> 15 #include <linux/of.h> 16 #include <linux/of_platform.h> 17 #include <linux/platform_device.h> 18 #include <linux/printk.h> 19 #include <linux/property.h> 20 #include <linux/types.h> 21 #include <linux/sizes.h> 22 #include <linux/slab.h> 23 24 #include <linux/firmware/meson/meson_sm.h> 25 26 struct meson_sm_cmd { 27 unsigned int index; 28 u32 smc_id; 29 }; 30 #define CMD(d, s) { .index = (d), .smc_id = (s), } 31 32 struct meson_sm_chip { 33 unsigned int shmem_size; 34 u32 cmd_shmem_in_base; 35 u32 cmd_shmem_out_base; 36 struct meson_sm_cmd cmd[]; 37 }; 38 39 static const struct meson_sm_chip gxbb_chip = { 40 .shmem_size = SZ_4K, 41 .cmd_shmem_in_base = 0x82000020, 42 .cmd_shmem_out_base = 0x82000021, 43 .cmd = { 44 CMD(SM_EFUSE_READ, 0x82000030), 45 CMD(SM_EFUSE_WRITE, 0x82000031), 46 CMD(SM_EFUSE_USER_MAX, 0x82000033), 47 CMD(SM_GET_CHIP_ID, 0x82000044), 48 CMD(SM_THERMAL_CALIB_READ, 0x82000047), 49 CMD(SM_A1_PWRC_SET, 0x82000093), 50 CMD(SM_A1_PWRC_GET, 0x82000095), 51 { /* sentinel */ }, 52 }, 53 }; 54 55 struct meson_sm_firmware { 56 const struct meson_sm_chip *chip; 57 void __iomem *sm_shmem_in_base; 58 void __iomem *sm_shmem_out_base; 59 }; 60 61 static u32 meson_sm_get_cmd(const struct meson_sm_chip *chip, 62 unsigned int cmd_index) 63 { 64 const struct meson_sm_cmd *cmd = chip->cmd; 65 66 while (cmd->smc_id && cmd->index != cmd_index) 67 cmd++; 68 69 return cmd->smc_id; 70 } 71 72 static s32 __meson_sm_call(u32 cmd, u32 arg0, u32 arg1, u32 arg2, 73 u32 arg3, u32 arg4) 74 { 75 struct arm_smccc_res res; 76 77 arm_smccc_smc(cmd, arg0, arg1, arg2, arg3, arg4, 0, 0, &res); 78 return res.a0; 79 } 80 81 static void __iomem *meson_sm_map_shmem(u32 cmd_shmem, unsigned int size) 82 { 83 u32 sm_phy_base; 84 85 sm_phy_base = __meson_sm_call(cmd_shmem, 0, 0, 0, 0, 0); 86 if (!sm_phy_base) 87 return NULL; 88 89 return ioremap_cache(sm_phy_base, size); 90 } 91 92 /** 93 * meson_sm_call - generic SMC32 call to the secure-monitor 94 * 95 * @fw: Pointer to secure-monitor firmware 96 * @cmd_index: Index of the SMC32 function ID 97 * @ret: Returned value 98 * @arg0: SMC32 Argument 0 99 * @arg1: SMC32 Argument 1 100 * @arg2: SMC32 Argument 2 101 * @arg3: SMC32 Argument 3 102 * @arg4: SMC32 Argument 4 103 * 104 * Return: 0 on success, a negative value on error 105 */ 106 int meson_sm_call(struct meson_sm_firmware *fw, unsigned int cmd_index, 107 s32 *ret, u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4) 108 { 109 u32 cmd; 110 s32 lret; 111 112 if (!fw->chip) 113 return -ENOENT; 114 115 cmd = meson_sm_get_cmd(fw->chip, cmd_index); 116 if (!cmd) 117 return -EINVAL; 118 119 lret = __meson_sm_call(cmd, arg0, arg1, arg2, arg3, arg4); 120 121 if (ret) 122 *ret = lret; 123 124 return 0; 125 } 126 EXPORT_SYMBOL(meson_sm_call); 127 128 /** 129 * meson_sm_call_read - retrieve data from secure-monitor 130 * 131 * @fw: Pointer to secure-monitor firmware 132 * @buffer: Buffer to store the retrieved data 133 * @bsize: Size of the buffer 134 * @cmd_index: Index of the SMC32 function ID 135 * @arg0: SMC32 Argument 0 136 * @arg1: SMC32 Argument 1 137 * @arg2: SMC32 Argument 2 138 * @arg3: SMC32 Argument 3 139 * @arg4: SMC32 Argument 4 140 * 141 * Return: size of read data on success, a negative value on error 142 * When 0 is returned there is no guarantee about the amount of 143 * data read and bsize bytes are copied in buffer. 144 */ 145 int meson_sm_call_read(struct meson_sm_firmware *fw, void *buffer, 146 unsigned int bsize, unsigned int cmd_index, u32 arg0, 147 u32 arg1, u32 arg2, u32 arg3, u32 arg4) 148 { 149 s32 size; 150 int ret; 151 152 if (!fw->chip) 153 return -ENOENT; 154 155 if (!fw->chip->cmd_shmem_out_base) 156 return -EINVAL; 157 158 if (bsize > fw->chip->shmem_size) 159 return -EINVAL; 160 161 if (meson_sm_call(fw, cmd_index, &size, arg0, arg1, arg2, arg3, arg4) < 0) 162 return -EINVAL; 163 164 if (size < 0 || size > bsize) 165 return -EINVAL; 166 167 ret = size; 168 169 /* In some cases (for example GET_CHIP_ID command), 170 * SMC doesn't return the number of bytes read, even 171 * though the bytes were actually read into sm_shmem_out. 172 * So this check is needed. 173 */ 174 if (!size) 175 size = bsize; 176 177 if (buffer) 178 memcpy(buffer, fw->sm_shmem_out_base, size); 179 180 return ret; 181 } 182 EXPORT_SYMBOL(meson_sm_call_read); 183 184 /** 185 * meson_sm_call_write - send data to secure-monitor 186 * 187 * @fw: Pointer to secure-monitor firmware 188 * @buffer: Buffer containing data to send 189 * @size: Size of the data to send 190 * @cmd_index: Index of the SMC32 function ID 191 * @arg0: SMC32 Argument 0 192 * @arg1: SMC32 Argument 1 193 * @arg2: SMC32 Argument 2 194 * @arg3: SMC32 Argument 3 195 * @arg4: SMC32 Argument 4 196 * 197 * Return: size of sent data on success, a negative value on error 198 */ 199 int meson_sm_call_write(struct meson_sm_firmware *fw, void *buffer, 200 unsigned int size, unsigned int cmd_index, u32 arg0, 201 u32 arg1, u32 arg2, u32 arg3, u32 arg4) 202 { 203 s32 written; 204 205 if (!fw->chip) 206 return -ENOENT; 207 208 if (size > fw->chip->shmem_size) 209 return -EINVAL; 210 211 if (!fw->chip->cmd_shmem_in_base) 212 return -EINVAL; 213 214 memcpy(fw->sm_shmem_in_base, buffer, size); 215 216 if (meson_sm_call(fw, cmd_index, &written, arg0, arg1, arg2, arg3, arg4) < 0) 217 return -EINVAL; 218 219 if (written <= 0 || written > size) 220 return -EINVAL; 221 222 return written; 223 } 224 EXPORT_SYMBOL(meson_sm_call_write); 225 226 /** 227 * meson_sm_get - get pointer to meson_sm_firmware structure. 228 * 229 * @sm_node: Pointer to the secure-monitor Device Tree node. 230 * 231 * Return: NULL is the secure-monitor device is not ready. 232 */ 233 struct meson_sm_firmware *meson_sm_get(struct device_node *sm_node) 234 { 235 struct platform_device *pdev = of_find_device_by_node(sm_node); 236 struct meson_sm_firmware *fw; 237 238 if (!pdev) 239 return NULL; 240 241 fw = platform_get_drvdata(pdev); 242 243 put_device(&pdev->dev); 244 245 return fw; 246 } 247 EXPORT_SYMBOL_GPL(meson_sm_get); 248 249 /** 250 * meson_sm_get_thermal_calib - Read thermal sensor calibration data. 251 * @fw: Pointer to secure-monitor firmware. 252 * @trim_info: Pointer to store the returned calibration data. 253 * @tsensor_id: Sensor index to identify which sensor's calibration data 254 * to retrieve 255 * 256 * Return: 0 on success, negative error code on failure. 257 */ 258 int meson_sm_get_thermal_calib(struct meson_sm_firmware *fw, u32 *trim_info, 259 u32 tsensor_id) 260 { 261 return meson_sm_call(fw, SM_THERMAL_CALIB_READ, trim_info, tsensor_id, 262 0, 0, 0, 0); 263 } 264 EXPORT_SYMBOL_GPL(meson_sm_get_thermal_calib); 265 266 #define SM_CHIP_ID_LENGTH 119 267 #define SM_CHIP_ID_OFFSET 4 268 #define SM_CHIP_ID_SIZE 12 269 270 static ssize_t serial_show(struct device *dev, struct device_attribute *attr, 271 char *buf) 272 { 273 struct platform_device *pdev = to_platform_device(dev); 274 struct meson_sm_firmware *fw; 275 uint8_t *id_buf; 276 int ret; 277 278 fw = platform_get_drvdata(pdev); 279 280 id_buf = kmalloc(SM_CHIP_ID_LENGTH, GFP_KERNEL); 281 if (!id_buf) 282 return -ENOMEM; 283 284 ret = meson_sm_call_read(fw, id_buf, SM_CHIP_ID_LENGTH, SM_GET_CHIP_ID, 285 0, 0, 0, 0, 0); 286 if (ret < 0) { 287 kfree(id_buf); 288 return ret; 289 } 290 291 ret = sprintf(buf, "%12phN\n", &id_buf[SM_CHIP_ID_OFFSET]); 292 293 kfree(id_buf); 294 295 return ret; 296 } 297 298 static DEVICE_ATTR_RO(serial); 299 300 static struct attribute *meson_sm_sysfs_attrs[] = { 301 &dev_attr_serial.attr, 302 NULL, 303 }; 304 ATTRIBUTE_GROUPS(meson_sm_sysfs); 305 306 static const struct of_device_id meson_sm_ids[] = { 307 { .compatible = "amlogic,meson-gxbb-sm", .data = &gxbb_chip }, 308 { /* sentinel */ }, 309 }; 310 311 static int __init meson_sm_probe(struct platform_device *pdev) 312 { 313 struct device *dev = &pdev->dev; 314 const struct meson_sm_chip *chip; 315 struct meson_sm_firmware *fw; 316 317 fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL); 318 if (!fw) 319 return -ENOMEM; 320 321 chip = device_get_match_data(dev); 322 if (!chip) 323 return -EINVAL; 324 325 if (chip->cmd_shmem_in_base) { 326 fw->sm_shmem_in_base = meson_sm_map_shmem(chip->cmd_shmem_in_base, 327 chip->shmem_size); 328 if (WARN_ON(!fw->sm_shmem_in_base)) 329 goto out; 330 } 331 332 if (chip->cmd_shmem_out_base) { 333 fw->sm_shmem_out_base = meson_sm_map_shmem(chip->cmd_shmem_out_base, 334 chip->shmem_size); 335 if (WARN_ON(!fw->sm_shmem_out_base)) 336 goto unmap_in_base; 337 } 338 339 fw->chip = chip; 340 341 platform_set_drvdata(pdev, fw); 342 343 if (devm_of_platform_populate(dev)) 344 goto unmap_out_base; 345 346 pr_info("secure-monitor enabled\n"); 347 348 return 0; 349 350 unmap_out_base: 351 iounmap(fw->sm_shmem_out_base); 352 unmap_in_base: 353 iounmap(fw->sm_shmem_in_base); 354 out: 355 return -EINVAL; 356 } 357 358 static struct platform_driver meson_sm_driver = { 359 .driver = { 360 .name = "meson-sm", 361 .of_match_table = of_match_ptr(meson_sm_ids), 362 .dev_groups = meson_sm_sysfs_groups, 363 }, 364 }; 365 module_platform_driver_probe(meson_sm_driver, meson_sm_probe); 366 MODULE_DESCRIPTION("Amlogic Secure Monitor driver"); 367 MODULE_LICENSE("GPL v2"); 368