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 1000
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 */
qfprom_disable_fuse_blowing(const struct qfprom_priv * priv,const struct qfprom_touched_values * old)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 */
qfprom_enable_fuse_blowing(const struct qfprom_priv * priv,struct qfprom_touched_values * old)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_get_sync(priv->dev);
221 if (ret < 0) {
222 pm_runtime_put_noidle(priv->dev);
223 dev_err(priv->dev, "Failed to enable power-domain\n");
224 goto err_reg_enable;
225 }
226 dev_pm_genpd_set_performance_state(priv->dev, INT_MAX);
227
228 old->timer_val = readl(priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET);
229 old->accel_val = readl(priv->qfpconf + QFPROM_ACCEL_OFFSET);
230 writel(priv->soc_data->qfprom_blow_timer_value,
231 priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET);
232 writel(priv->soc_data->accel_value,
233 priv->qfpconf + QFPROM_ACCEL_OFFSET);
234
235 return 0;
236
237 err_reg_enable:
238 regulator_disable(priv->vcc);
239 err_clk_rate_set:
240 clk_set_rate(priv->secclk, old->clk_rate);
241 err_clk_prepared:
242 clk_disable_unprepare(priv->secclk);
243 return ret;
244 }
245
246 /**
247 * qfprom_efuse_reg_write() - Write to fuses.
248 * @context: Our driver data.
249 * @reg: The offset to write at.
250 * @_val: Pointer to data to write.
251 * @bytes: The number of bytes to write.
252 *
253 * Writes to fuses. WARNING: THIS IS PERMANENT.
254 *
255 * Return: 0 or -err.
256 */
qfprom_reg_write(void * context,unsigned int reg,void * _val,size_t bytes)257 static int qfprom_reg_write(void *context, unsigned int reg, void *_val,
258 size_t bytes)
259 {
260 struct qfprom_priv *priv = context;
261 struct qfprom_touched_values old;
262 int words = bytes / 4;
263 u32 *value = _val;
264 u32 blow_status;
265 int ret;
266 int i;
267
268 dev_dbg(priv->dev,
269 "Writing to raw qfprom region : %#010x of size: %zu\n",
270 reg, bytes);
271
272 /*
273 * The hardware only allows us to write word at a time, but we can
274 * read byte at a time. Until the nvmem framework allows a separate
275 * word_size and stride for reading vs. writing, we'll enforce here.
276 */
277 if (bytes % 4) {
278 dev_err(priv->dev,
279 "%zu is not an integral number of words\n", bytes);
280 return -EINVAL;
281 }
282 if (reg % 4) {
283 dev_err(priv->dev,
284 "Invalid offset: %#x. Must be word aligned\n", reg);
285 return -EINVAL;
286 }
287
288 ret = qfprom_enable_fuse_blowing(priv, &old);
289 if (ret)
290 return ret;
291
292 ret = readl_relaxed_poll_timeout(
293 priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET,
294 blow_status, blow_status == QFPROM_BLOW_STATUS_READY,
295 QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US);
296
297 if (ret) {
298 dev_err(priv->dev,
299 "Timeout waiting for initial ready; aborting.\n");
300 goto exit_enabled_fuse_blowing;
301 }
302
303 for (i = 0; i < words; i++)
304 writel(value[i], priv->qfpraw + reg + (i * 4));
305
306 ret = readl_relaxed_poll_timeout(
307 priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET,
308 blow_status, blow_status == QFPROM_BLOW_STATUS_READY,
309 QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US);
310
311 /* Give an error, but not much we can do in this case */
312 if (ret)
313 dev_err(priv->dev, "Timeout waiting for finish.\n");
314
315 exit_enabled_fuse_blowing:
316 qfprom_disable_fuse_blowing(priv, &old);
317
318 return ret;
319 }
320
qfprom_reg_read(void * context,unsigned int reg,void * _val,size_t bytes)321 static int qfprom_reg_read(void *context,
322 unsigned int reg, void *_val, size_t bytes)
323 {
324 struct qfprom_priv *priv = context;
325 u8 *val = _val;
326 int i = 0, words = bytes;
327 void __iomem *base = priv->qfpcorrected;
328
329 if (read_raw_data && priv->qfpraw)
330 base = priv->qfpraw;
331
332 while (words--)
333 *val++ = readb(base + reg + i++);
334
335 return 0;
336 }
337
qfprom_runtime_disable(void * data)338 static void qfprom_runtime_disable(void *data)
339 {
340 pm_runtime_disable(data);
341 }
342
343 static const struct qfprom_soc_data qfprom_7_8_data = {
344 .accel_value = 0xD10,
345 .qfprom_blow_timer_value = 25,
346 .qfprom_blow_set_freq = 4800000,
347 .qfprom_blow_uV = 1800000,
348 };
349
350 static const struct qfprom_soc_data qfprom_7_15_data = {
351 .accel_value = 0xD08,
352 .qfprom_blow_timer_value = 24,
353 .qfprom_blow_set_freq = 4800000,
354 .qfprom_blow_uV = 1900000,
355 };
356
qfprom_probe(struct platform_device * pdev)357 static int qfprom_probe(struct platform_device *pdev)
358 {
359 struct nvmem_config econfig = {
360 .name = "qfprom",
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 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
379 priv->qfpcorrected = devm_ioremap_resource(dev, res);
380 if (IS_ERR(priv->qfpcorrected))
381 return PTR_ERR(priv->qfpcorrected);
382
383 econfig.size = resource_size(res);
384 econfig.dev = dev;
385 econfig.priv = priv;
386
387 priv->dev = dev;
388 soc_data = device_get_match_data(dev);
389 if (soc_data) {
390 econfig.keepout = soc_data->keepout;
391 econfig.nkeepout = soc_data->nkeepout;
392 }
393
394 /*
395 * If more than one region is provided then the OS has the ability
396 * to write.
397 */
398 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
399 if (res) {
400 u32 version;
401 int major_version, minor_version;
402
403 priv->qfpraw = devm_ioremap_resource(dev, res);
404 if (IS_ERR(priv->qfpraw))
405 return PTR_ERR(priv->qfpraw);
406 res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
407 priv->qfpconf = devm_ioremap_resource(dev, res);
408 if (IS_ERR(priv->qfpconf))
409 return PTR_ERR(priv->qfpconf);
410 res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
411 priv->qfpsecurity = devm_ioremap_resource(dev, res);
412 if (IS_ERR(priv->qfpsecurity))
413 return PTR_ERR(priv->qfpsecurity);
414
415 version = readl(priv->qfpsecurity + QFPROM_VERSION_OFFSET);
416 major_version = (version & QFPROM_MAJOR_VERSION_MASK) >>
417 QFPROM_MAJOR_VERSION_SHIFT;
418 minor_version = (version & QFPROM_MINOR_VERSION_MASK) >>
419 QFPROM_MINOR_VERSION_SHIFT;
420
421 if (major_version == 7 && minor_version == 8)
422 priv->soc_data = &qfprom_7_8_data;
423 else if (major_version == 7 && minor_version == 15)
424 priv->soc_data = &qfprom_7_15_data;
425
426 priv->vcc = devm_regulator_get(&pdev->dev, "vcc");
427 if (IS_ERR(priv->vcc))
428 return PTR_ERR(priv->vcc);
429
430 priv->secclk = devm_clk_get(dev, "core");
431 if (IS_ERR(priv->secclk)) {
432 ret = PTR_ERR(priv->secclk);
433 if (ret != -EPROBE_DEFER)
434 dev_err(dev, "Error getting clock: %d\n", ret);
435 return ret;
436 }
437
438 /* Only enable writing if we have SoC data. */
439 if (priv->soc_data)
440 econfig.reg_write = qfprom_reg_write;
441 }
442
443 pm_runtime_enable(dev);
444 ret = devm_add_action_or_reset(dev, qfprom_runtime_disable, dev);
445 if (ret)
446 return ret;
447
448 nvmem = devm_nvmem_register(dev, &econfig);
449
450 return PTR_ERR_OR_ZERO(nvmem);
451 }
452
453 static const struct of_device_id qfprom_of_match[] = {
454 { .compatible = "qcom,qfprom",},
455 { .compatible = "qcom,sc7180-qfprom", .data = &sc7180_qfprom},
456 { .compatible = "qcom,sc7280-qfprom", .data = &sc7280_qfprom},
457 {/* sentinel */},
458 };
459 MODULE_DEVICE_TABLE(of, qfprom_of_match);
460
461 static struct platform_driver qfprom_driver = {
462 .probe = qfprom_probe,
463 .driver = {
464 .name = "qcom,qfprom",
465 .of_match_table = qfprom_of_match,
466 },
467 };
468 module_platform_driver(qfprom_driver);
469 MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>");
470 MODULE_DESCRIPTION("Qualcomm QFPROM driver");
471 MODULE_LICENSE("GPL v2");
472