1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org> 4 */ 5 6 #include <linux/clk.h> 7 #include <linux/device.h> 8 #include <linux/io.h> 9 #include <linux/iopoll.h> 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/mod_devicetable.h> 13 #include <linux/nvmem-provider.h> 14 #include <linux/platform_device.h> 15 #include <linux/pm_domain.h> 16 #include <linux/pm_runtime.h> 17 #include <linux/property.h> 18 #include <linux/regulator/consumer.h> 19 20 /* Blow timer clock frequency in Mhz */ 21 #define QFPROM_BLOW_TIMER_OFFSET 0x03c 22 23 /* Amount of time required to hold charge to blow fuse in micro-seconds */ 24 #define QFPROM_FUSE_BLOW_POLL_US 100 25 #define QFPROM_FUSE_BLOW_TIMEOUT_US 10000 26 27 #define QFPROM_BLOW_STATUS_OFFSET 0x048 28 #define QFPROM_BLOW_STATUS_BUSY 0x1 29 #define QFPROM_BLOW_STATUS_READY 0x0 30 31 #define QFPROM_ACCEL_OFFSET 0x044 32 33 #define QFPROM_VERSION_OFFSET 0x0 34 #define QFPROM_MAJOR_VERSION_SHIFT 28 35 #define QFPROM_MAJOR_VERSION_MASK GENMASK(31, QFPROM_MAJOR_VERSION_SHIFT) 36 #define QFPROM_MINOR_VERSION_SHIFT 16 37 #define QFPROM_MINOR_VERSION_MASK GENMASK(27, QFPROM_MINOR_VERSION_SHIFT) 38 39 static bool read_raw_data; 40 module_param(read_raw_data, bool, 0644); 41 MODULE_PARM_DESC(read_raw_data, "Read raw instead of corrected data"); 42 43 /** 44 * struct qfprom_soc_data - config that varies from SoC to SoC. 45 * 46 * @accel_value: Should contain qfprom accel value. 47 * @qfprom_blow_timer_value: The timer value of qfprom when doing efuse blow. 48 * @qfprom_blow_set_freq: The frequency required to set when we start the 49 * fuse blowing. 50 * @qfprom_blow_uV: LDO voltage to be set when doing efuse blow 51 */ 52 struct qfprom_soc_data { 53 u32 accel_value; 54 u32 qfprom_blow_timer_value; 55 u32 qfprom_blow_set_freq; 56 int qfprom_blow_uV; 57 }; 58 59 /** 60 * struct qfprom_priv - structure holding qfprom attributes 61 * 62 * @qfpraw: iomapped memory space for qfprom-efuse raw address space. 63 * @qfpconf: iomapped memory space for qfprom-efuse configuration address 64 * space. 65 * @qfpcorrected: iomapped memory space for qfprom corrected address space. 66 * @qfpsecurity: iomapped memory space for qfprom security control space. 67 * @dev: qfprom device structure. 68 * @secclk: Clock supply. 69 * @vcc: Regulator supply. 70 * @soc_data: Data that for things that varies from SoC to SoC. 71 */ 72 struct qfprom_priv { 73 void __iomem *qfpraw; 74 void __iomem *qfpconf; 75 void __iomem *qfpcorrected; 76 void __iomem *qfpsecurity; 77 struct device *dev; 78 struct clk *secclk; 79 struct regulator *vcc; 80 const struct qfprom_soc_data *soc_data; 81 }; 82 83 /** 84 * struct qfprom_touched_values - saved values to restore after blowing 85 * 86 * @clk_rate: The rate the clock was at before blowing. 87 * @accel_val: The value of the accel reg before blowing. 88 * @timer_val: The value of the timer before blowing. 89 */ 90 struct qfprom_touched_values { 91 unsigned long clk_rate; 92 u32 accel_val; 93 u32 timer_val; 94 }; 95 96 /** 97 * struct qfprom_soc_compatible_data - Data matched against the SoC 98 * compatible string. 99 * 100 * @keepout: Array of keepout regions for this SoC. 101 * @nkeepout: Number of elements in the keepout array. 102 */ 103 struct qfprom_soc_compatible_data { 104 const struct nvmem_keepout *keepout; 105 unsigned int nkeepout; 106 }; 107 108 static const struct nvmem_keepout sc7180_qfprom_keepout[] = { 109 {.start = 0x128, .end = 0x148}, 110 {.start = 0x220, .end = 0x228} 111 }; 112 113 static const struct qfprom_soc_compatible_data sc7180_qfprom = { 114 .keepout = sc7180_qfprom_keepout, 115 .nkeepout = ARRAY_SIZE(sc7180_qfprom_keepout) 116 }; 117 118 static const struct nvmem_keepout sc7280_qfprom_keepout[] = { 119 {.start = 0x128, .end = 0x148}, 120 {.start = 0x238, .end = 0x248} 121 }; 122 123 static const struct qfprom_soc_compatible_data sc7280_qfprom = { 124 .keepout = sc7280_qfprom_keepout, 125 .nkeepout = ARRAY_SIZE(sc7280_qfprom_keepout) 126 }; 127 128 /** 129 * qfprom_disable_fuse_blowing() - Undo enabling of fuse blowing. 130 * @priv: Our driver data. 131 * @old: The data that was stashed from before fuse blowing. 132 * 133 * Resets the value of the blow timer, accel register and the clock 134 * and voltage settings. 135 * 136 * Prints messages if there are errors but doesn't return an error code 137 * since there's not much we can do upon failure. 138 */ 139 static void qfprom_disable_fuse_blowing(const struct qfprom_priv *priv, 140 const struct qfprom_touched_values *old) 141 { 142 int ret; 143 144 writel(old->timer_val, priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); 145 writel(old->accel_val, priv->qfpconf + QFPROM_ACCEL_OFFSET); 146 147 dev_pm_genpd_set_performance_state(priv->dev, 0); 148 pm_runtime_put(priv->dev); 149 150 /* 151 * This may be a shared rail and may be able to run at a lower rate 152 * when we're not blowing fuses. At the moment, the regulator framework 153 * applies voltage constraints even on disabled rails, so remove our 154 * constraints and allow the rail to be adjusted by other users. 155 */ 156 ret = regulator_set_voltage(priv->vcc, 0, INT_MAX); 157 if (ret) 158 dev_warn(priv->dev, "Failed to set 0 voltage (ignoring)\n"); 159 160 ret = regulator_disable(priv->vcc); 161 if (ret) 162 dev_warn(priv->dev, "Failed to disable regulator (ignoring)\n"); 163 164 ret = clk_set_rate(priv->secclk, old->clk_rate); 165 if (ret) 166 dev_warn(priv->dev, 167 "Failed to set clock rate for disable (ignoring)\n"); 168 169 clk_disable_unprepare(priv->secclk); 170 } 171 172 /** 173 * qfprom_enable_fuse_blowing() - Enable fuse blowing. 174 * @priv: Our driver data. 175 * @old: We'll stash stuff here to use when disabling. 176 * 177 * Sets the value of the blow timer, accel register and the clock 178 * and voltage settings. 179 * 180 * Prints messages if there are errors so caller doesn't need to. 181 * 182 * Return: 0 or -err. 183 */ 184 static int qfprom_enable_fuse_blowing(const struct qfprom_priv *priv, 185 struct qfprom_touched_values *old) 186 { 187 int ret; 188 int qfprom_blow_uV = priv->soc_data->qfprom_blow_uV; 189 190 ret = clk_prepare_enable(priv->secclk); 191 if (ret) { 192 dev_err(priv->dev, "Failed to enable clock\n"); 193 return ret; 194 } 195 196 old->clk_rate = clk_get_rate(priv->secclk); 197 ret = clk_set_rate(priv->secclk, priv->soc_data->qfprom_blow_set_freq); 198 if (ret) { 199 dev_err(priv->dev, "Failed to set clock rate for enable\n"); 200 goto err_clk_prepared; 201 } 202 203 /* 204 * Hardware requires a minimum voltage for fuse blowing. 205 * This may be a shared rail so don't specify a maximum. 206 * Regulator constraints will cap to the actual maximum. 207 */ 208 ret = regulator_set_voltage(priv->vcc, qfprom_blow_uV, INT_MAX); 209 if (ret) { 210 dev_err(priv->dev, "Failed to set %duV\n", qfprom_blow_uV); 211 goto err_clk_rate_set; 212 } 213 214 ret = regulator_enable(priv->vcc); 215 if (ret) { 216 dev_err(priv->dev, "Failed to enable regulator\n"); 217 goto err_clk_rate_set; 218 } 219 220 ret = pm_runtime_resume_and_get(priv->dev); 221 if (ret < 0) { 222 dev_err(priv->dev, "Failed to enable power-domain\n"); 223 goto err_reg_enable; 224 } 225 dev_pm_genpd_set_performance_state(priv->dev, INT_MAX); 226 227 old->timer_val = readl(priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); 228 old->accel_val = readl(priv->qfpconf + QFPROM_ACCEL_OFFSET); 229 writel(priv->soc_data->qfprom_blow_timer_value, 230 priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); 231 writel(priv->soc_data->accel_value, 232 priv->qfpconf + QFPROM_ACCEL_OFFSET); 233 234 return 0; 235 236 err_reg_enable: 237 regulator_disable(priv->vcc); 238 err_clk_rate_set: 239 clk_set_rate(priv->secclk, old->clk_rate); 240 err_clk_prepared: 241 clk_disable_unprepare(priv->secclk); 242 return ret; 243 } 244 245 /** 246 * qfprom_reg_write() - Write to fuses. 247 * @context: Our driver data. 248 * @reg: The offset to write at. 249 * @_val: Pointer to data to write. 250 * @bytes: The number of bytes to write. 251 * 252 * Writes to fuses. WARNING: THIS IS PERMANENT. 253 * 254 * Return: 0 or -err. 255 */ 256 static int qfprom_reg_write(void *context, unsigned int reg, void *_val, 257 size_t bytes) 258 { 259 struct qfprom_priv *priv = context; 260 struct qfprom_touched_values old; 261 int words = bytes / 4; 262 u32 *value = _val; 263 u32 blow_status; 264 int ret; 265 int i; 266 267 dev_dbg(priv->dev, 268 "Writing to raw qfprom region : %#010x of size: %zu\n", 269 reg, bytes); 270 271 /* 272 * The hardware only allows us to write word at a time, but we can 273 * read byte at a time. Until the nvmem framework allows a separate 274 * word_size and stride for reading vs. writing, we'll enforce here. 275 */ 276 if (bytes % 4) { 277 dev_err(priv->dev, 278 "%zu is not an integral number of words\n", bytes); 279 return -EINVAL; 280 } 281 if (reg % 4) { 282 dev_err(priv->dev, 283 "Invalid offset: %#x. Must be word aligned\n", reg); 284 return -EINVAL; 285 } 286 287 ret = qfprom_enable_fuse_blowing(priv, &old); 288 if (ret) 289 return ret; 290 291 ret = readl_relaxed_poll_timeout( 292 priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET, 293 blow_status, blow_status == QFPROM_BLOW_STATUS_READY, 294 QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US); 295 296 if (ret) { 297 dev_err(priv->dev, 298 "Timeout waiting for initial ready; aborting.\n"); 299 goto exit_enabled_fuse_blowing; 300 } 301 302 for (i = 0; i < words; i++) 303 writel(value[i], priv->qfpraw + reg + (i * 4)); 304 305 ret = readl_relaxed_poll_timeout( 306 priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET, 307 blow_status, blow_status == QFPROM_BLOW_STATUS_READY, 308 QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US); 309 310 /* Give an error, but not much we can do in this case */ 311 if (ret) 312 dev_err(priv->dev, "Timeout waiting for finish.\n"); 313 314 exit_enabled_fuse_blowing: 315 qfprom_disable_fuse_blowing(priv, &old); 316 317 return ret; 318 } 319 320 static int qfprom_reg_read(void *context, 321 unsigned int reg, void *_val, size_t bytes) 322 { 323 struct qfprom_priv *priv = context; 324 u8 *val = _val; 325 int i = 0, words = bytes; 326 void __iomem *base = priv->qfpcorrected; 327 328 if (read_raw_data && priv->qfpraw) 329 base = priv->qfpraw; 330 331 while (words--) 332 *val++ = readb(base + reg + i++); 333 334 return 0; 335 } 336 337 static void qfprom_runtime_disable(void *data) 338 { 339 pm_runtime_disable(data); 340 } 341 342 static const struct qfprom_soc_data qfprom_7_8_data = { 343 .accel_value = 0xD10, 344 .qfprom_blow_timer_value = 25, 345 .qfprom_blow_set_freq = 4800000, 346 .qfprom_blow_uV = 1800000, 347 }; 348 349 static const struct qfprom_soc_data qfprom_7_15_data = { 350 .accel_value = 0xD08, 351 .qfprom_blow_timer_value = 24, 352 .qfprom_blow_set_freq = 4800000, 353 .qfprom_blow_uV = 1900000, 354 }; 355 356 static int qfprom_probe(struct platform_device *pdev) 357 { 358 struct nvmem_config econfig = { 359 .name = "qfprom", 360 .add_legacy_fixed_of_cells = true, 361 .stride = 1, 362 .word_size = 1, 363 .id = NVMEM_DEVID_AUTO, 364 .reg_read = qfprom_reg_read, 365 }; 366 struct device *dev = &pdev->dev; 367 struct resource *res; 368 struct nvmem_device *nvmem; 369 const struct qfprom_soc_compatible_data *soc_data; 370 struct qfprom_priv *priv; 371 int ret; 372 373 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 374 if (!priv) 375 return -ENOMEM; 376 377 /* The corrected section is always provided */ 378 priv->qfpcorrected = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 379 if (IS_ERR(priv->qfpcorrected)) 380 return PTR_ERR(priv->qfpcorrected); 381 382 econfig.size = resource_size(res); 383 econfig.dev = dev; 384 econfig.priv = priv; 385 386 priv->dev = dev; 387 soc_data = device_get_match_data(dev); 388 if (soc_data) { 389 econfig.keepout = soc_data->keepout; 390 econfig.nkeepout = soc_data->nkeepout; 391 } 392 393 /* 394 * If more than one region is provided then the OS has the ability 395 * to write. 396 */ 397 res = platform_get_resource(pdev, IORESOURCE_MEM, 1); 398 if (res) { 399 u32 version; 400 int major_version, minor_version; 401 402 priv->qfpraw = devm_ioremap_resource(dev, res); 403 if (IS_ERR(priv->qfpraw)) 404 return PTR_ERR(priv->qfpraw); 405 priv->qfpconf = devm_platform_ioremap_resource(pdev, 2); 406 if (IS_ERR(priv->qfpconf)) 407 return PTR_ERR(priv->qfpconf); 408 priv->qfpsecurity = devm_platform_ioremap_resource(pdev, 3); 409 if (IS_ERR(priv->qfpsecurity)) 410 return PTR_ERR(priv->qfpsecurity); 411 412 version = readl(priv->qfpsecurity + QFPROM_VERSION_OFFSET); 413 major_version = (version & QFPROM_MAJOR_VERSION_MASK) >> 414 QFPROM_MAJOR_VERSION_SHIFT; 415 minor_version = (version & QFPROM_MINOR_VERSION_MASK) >> 416 QFPROM_MINOR_VERSION_SHIFT; 417 418 if (major_version == 7 && minor_version == 8) 419 priv->soc_data = &qfprom_7_8_data; 420 else if (major_version == 7 && minor_version == 15) 421 priv->soc_data = &qfprom_7_15_data; 422 423 priv->vcc = devm_regulator_get(&pdev->dev, "vcc"); 424 if (IS_ERR(priv->vcc)) 425 return PTR_ERR(priv->vcc); 426 427 priv->secclk = devm_clk_get_optional(dev, "core"); 428 if (IS_ERR(priv->secclk)) 429 return dev_err_probe(dev, PTR_ERR(priv->secclk), "Error getting clock\n"); 430 431 /* Only enable writing if we have SoC data and a valid clock */ 432 if (priv->soc_data && priv->secclk) 433 econfig.reg_write = qfprom_reg_write; 434 } 435 436 pm_runtime_enable(dev); 437 ret = devm_add_action_or_reset(dev, qfprom_runtime_disable, dev); 438 if (ret) 439 return ret; 440 441 nvmem = devm_nvmem_register(dev, &econfig); 442 443 return PTR_ERR_OR_ZERO(nvmem); 444 } 445 446 static const struct of_device_id qfprom_of_match[] = { 447 { .compatible = "qcom,qfprom",}, 448 { .compatible = "qcom,sc7180-qfprom", .data = &sc7180_qfprom}, 449 { .compatible = "qcom,sc7280-qfprom", .data = &sc7280_qfprom}, 450 {/* sentinel */}, 451 }; 452 MODULE_DEVICE_TABLE(of, qfprom_of_match); 453 454 static struct platform_driver qfprom_driver = { 455 .probe = qfprom_probe, 456 .driver = { 457 .name = "qcom,qfprom", 458 .of_match_table = qfprom_of_match, 459 }, 460 }; 461 module_platform_driver(qfprom_driver); 462 MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>"); 463 MODULE_DESCRIPTION("Qualcomm QFPROM driver"); 464 MODULE_LICENSE("GPL v2"); 465