xref: /linux/drivers/mfd/intel_pmc_bxt.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for the Intel Broxton PMC
4  *
5  * (C) Copyright 2014 - 2020 Intel Corporation
6  *
7  * This driver is based on Intel SCU IPC driver (intel_scu_ipc.c) by
8  * Sreedhara DS <sreedhara.ds@intel.com>
9  *
10  * The PMC (Power Management Controller) running on the ARC processor
11  * communicates with another entity running in the IA (Intel Architecture)
12  * core through an IPC (Intel Processor Communications) mechanism which in
13  * turn sends messages between the IA and the PMC.
14  */
15 
16 #include <linux/acpi.h>
17 #include <linux/delay.h>
18 #include <linux/errno.h>
19 #include <linux/interrupt.h>
20 #include <linux/io-64-nonatomic-lo-hi.h>
21 #include <linux/mfd/core.h>
22 #include <linux/mfd/intel_pmc_bxt.h>
23 #include <linux/module.h>
24 #include <linux/platform_device.h>
25 #include <linux/platform_data/itco_wdt.h>
26 #include <linux/platform_data/x86/intel_scu_ipc.h>
27 
28 /* Residency with clock rate at 19.2MHz to usecs */
29 #define S0IX_RESIDENCY_IN_USECS(d, s)		\
30 ({						\
31 	u64 result = 10ull * ((d) + (s));	\
32 	do_div(result, 192);			\
33 	result;					\
34 })
35 
36 /* Resources exported from IFWI */
37 #define PLAT_RESOURCE_IPC_INDEX		0
38 #define PLAT_RESOURCE_IPC_SIZE		0x1000
39 #define PLAT_RESOURCE_GCR_OFFSET	0x1000
40 #define PLAT_RESOURCE_GCR_SIZE		0x1000
41 #define PLAT_RESOURCE_BIOS_DATA_INDEX	1
42 #define PLAT_RESOURCE_BIOS_IFACE_INDEX	2
43 #define PLAT_RESOURCE_TELEM_SSRAM_INDEX	3
44 #define PLAT_RESOURCE_ISP_DATA_INDEX	4
45 #define PLAT_RESOURCE_ISP_IFACE_INDEX	5
46 #define PLAT_RESOURCE_GTD_DATA_INDEX	6
47 #define PLAT_RESOURCE_GTD_IFACE_INDEX	7
48 #define PLAT_RESOURCE_ACPI_IO_INDEX	0
49 
50 /*
51  * BIOS does not create an ACPI device for each PMC function, but
52  * exports multiple resources from one ACPI device (IPC) for multiple
53  * functions. This driver is responsible for creating a child device and
54  * to export resources for those functions.
55  */
56 #define SMI_EN_OFFSET			0x0040
57 #define SMI_EN_SIZE			4
58 #define TCO_BASE_OFFSET			0x0060
59 #define TCO_REGS_SIZE			16
60 #define TELEM_SSRAM_SIZE		240
61 #define TELEM_PMC_SSRAM_OFFSET		0x1b00
62 #define TELEM_PUNIT_SSRAM_OFFSET	0x1a00
63 
64 /* Commands */
65 #define PMC_NORTHPEAK_CTRL		0xed
66 
67 static inline bool is_gcr_valid(u32 offset)
68 {
69 	return offset < PLAT_RESOURCE_GCR_SIZE - 8;
70 }
71 
72 /**
73  * intel_pmc_gcr_read64() - Read a 64-bit PMC GCR register
74  * @pmc: PMC device pointer
75  * @offset: offset of GCR register from GCR address base
76  * @data: data pointer for storing the register output
77  *
78  * Reads the 64-bit PMC GCR register at given offset.
79  *
80  * Return: Negative value on error or 0 on success.
81  */
82 int intel_pmc_gcr_read64(struct intel_pmc_dev *pmc, u32 offset, u64 *data)
83 {
84 	if (!is_gcr_valid(offset))
85 		return -EINVAL;
86 
87 	spin_lock(&pmc->gcr_lock);
88 	*data = readq(pmc->gcr_mem_base + offset);
89 	spin_unlock(&pmc->gcr_lock);
90 
91 	return 0;
92 }
93 EXPORT_SYMBOL_GPL(intel_pmc_gcr_read64);
94 
95 /**
96  * intel_pmc_gcr_update() - Update PMC GCR register bits
97  * @pmc: PMC device pointer
98  * @offset: offset of GCR register from GCR address base
99  * @mask: bit mask for update operation
100  * @val: update value
101  *
102  * Updates the bits of given GCR register as specified by
103  * @mask and @val.
104  *
105  * Return: Negative value on error or 0 on success.
106  */
107 int intel_pmc_gcr_update(struct intel_pmc_dev *pmc, u32 offset, u32 mask, u32 val)
108 {
109 	u32 new_val;
110 
111 	if (!is_gcr_valid(offset))
112 		return -EINVAL;
113 
114 	spin_lock(&pmc->gcr_lock);
115 	new_val = readl(pmc->gcr_mem_base + offset);
116 
117 	new_val = (new_val & ~mask) | (val & mask);
118 	writel(new_val, pmc->gcr_mem_base + offset);
119 
120 	new_val = readl(pmc->gcr_mem_base + offset);
121 	spin_unlock(&pmc->gcr_lock);
122 
123 	/* Check whether the bit update is successful */
124 	return (new_val & mask) != (val & mask) ? -EIO : 0;
125 }
126 EXPORT_SYMBOL_GPL(intel_pmc_gcr_update);
127 
128 /**
129  * intel_pmc_s0ix_counter_read() - Read S0ix residency
130  * @pmc: PMC device pointer
131  * @data: Out param that contains current S0ix residency count.
132  *
133  * Writes to @data how many usecs the system has been in low-power S0ix
134  * state.
135  *
136  * Return: An error code or 0 on success.
137  */
138 int intel_pmc_s0ix_counter_read(struct intel_pmc_dev *pmc, u64 *data)
139 {
140 	u64 deep, shlw;
141 
142 	spin_lock(&pmc->gcr_lock);
143 	deep = readq(pmc->gcr_mem_base + PMC_GCR_TELEM_DEEP_S0IX_REG);
144 	shlw = readq(pmc->gcr_mem_base + PMC_GCR_TELEM_SHLW_S0IX_REG);
145 	spin_unlock(&pmc->gcr_lock);
146 
147 	*data = S0IX_RESIDENCY_IN_USECS(deep, shlw);
148 	return 0;
149 }
150 EXPORT_SYMBOL_GPL(intel_pmc_s0ix_counter_read);
151 
152 /**
153  * simplecmd_store() - Send a simple IPC command
154  * @dev: Device under the attribute is
155  * @attr: Attribute in question
156  * @buf: Buffer holding data to be stored to the attribute
157  * @count: Number of bytes in @buf
158  *
159  * Expects a string with two integers separated with space. These two
160  * values hold command and subcommand that is send to PMC.
161  *
162  * Return: Number number of bytes written (@count) or negative errno in
163  *	   case of error.
164  */
165 static ssize_t simplecmd_store(struct device *dev, struct device_attribute *attr,
166 			       const char *buf, size_t count)
167 {
168 	struct intel_pmc_dev *pmc = dev_get_drvdata(dev);
169 	struct intel_scu_ipc_dev *scu = pmc->scu;
170 	int subcmd;
171 	int cmd;
172 	int ret;
173 
174 	ret = sscanf(buf, "%d %d", &cmd, &subcmd);
175 	if (ret != 2) {
176 		dev_err(dev, "Invalid values, expected: cmd subcmd\n");
177 		return -EINVAL;
178 	}
179 
180 	ret = intel_scu_ipc_dev_simple_command(scu, cmd, subcmd);
181 	if (ret)
182 		return ret;
183 
184 	return count;
185 }
186 static DEVICE_ATTR_WO(simplecmd);
187 
188 /**
189  * northpeak_store() - Enable or disable Northpeak
190  * @dev: Device under the attribute is
191  * @attr: Attribute in question
192  * @buf: Buffer holding data to be stored to the attribute
193  * @count: Number of bytes in @buf
194  *
195  * Expects an unsigned integer. Non-zero enables Northpeak and zero
196  * disables it.
197  *
198  * Return: Number number of bytes written (@count) or negative errno in
199  *	   case of error.
200  */
201 static ssize_t northpeak_store(struct device *dev, struct device_attribute *attr,
202 			       const char *buf, size_t count)
203 {
204 	struct intel_pmc_dev *pmc = dev_get_drvdata(dev);
205 	struct intel_scu_ipc_dev *scu = pmc->scu;
206 	unsigned long val;
207 	int subcmd;
208 	int ret;
209 
210 	ret = kstrtoul(buf, 0, &val);
211 	if (ret)
212 		return ret;
213 
214 	/* Northpeak is enabled if subcmd == 1 and disabled if it is 0 */
215 	if (val)
216 		subcmd = 1;
217 	else
218 		subcmd = 0;
219 
220 	ret = intel_scu_ipc_dev_simple_command(scu, PMC_NORTHPEAK_CTRL, subcmd);
221 	if (ret)
222 		return ret;
223 
224 	return count;
225 }
226 static DEVICE_ATTR_WO(northpeak);
227 
228 static struct attribute *intel_pmc_attrs[] = {
229 	&dev_attr_northpeak.attr,
230 	&dev_attr_simplecmd.attr,
231 	NULL
232 };
233 
234 static const struct attribute_group intel_pmc_group = {
235 	.attrs = intel_pmc_attrs,
236 };
237 
238 static const struct attribute_group *intel_pmc_groups[] = {
239 	&intel_pmc_group,
240 	NULL
241 };
242 
243 static struct resource punit_res[6];
244 
245 static struct mfd_cell punit = {
246 	.name = "intel_punit_ipc",
247 	.resources = punit_res,
248 };
249 
250 static struct itco_wdt_platform_data tco_pdata = {
251 	.name = "Apollo Lake SoC",
252 	.version = 5,
253 	.no_reboot_use_pmc = true,
254 };
255 
256 static struct resource tco_res[2];
257 
258 static const struct mfd_cell tco = {
259 	.name = "iTCO_wdt",
260 	.ignore_resource_conflicts = true,
261 	.resources = tco_res,
262 	.num_resources = ARRAY_SIZE(tco_res),
263 	.platform_data = &tco_pdata,
264 	.pdata_size = sizeof(tco_pdata),
265 };
266 
267 static const struct resource telem_res[] = {
268 	DEFINE_RES_MEM(TELEM_PUNIT_SSRAM_OFFSET, TELEM_SSRAM_SIZE),
269 	DEFINE_RES_MEM(TELEM_PMC_SSRAM_OFFSET, TELEM_SSRAM_SIZE),
270 };
271 
272 static const struct mfd_cell telem = {
273 	.name = "intel_telemetry",
274 	.resources = telem_res,
275 	.num_resources = ARRAY_SIZE(telem_res),
276 };
277 
278 static int intel_pmc_get_tco_resources(struct platform_device *pdev)
279 {
280 	struct resource *res;
281 
282 	if (acpi_has_watchdog())
283 		return 0;
284 
285 	res = platform_get_resource(pdev, IORESOURCE_IO,
286 				    PLAT_RESOURCE_ACPI_IO_INDEX);
287 	if (!res) {
288 		dev_err(&pdev->dev, "Failed to get IO resource\n");
289 		return -EINVAL;
290 	}
291 
292 	tco_res[0].flags = IORESOURCE_IO;
293 	tco_res[0].start = res->start + TCO_BASE_OFFSET;
294 	tco_res[0].end = tco_res[0].start + TCO_REGS_SIZE - 1;
295 	tco_res[1].flags = IORESOURCE_IO;
296 	tco_res[1].start = res->start + SMI_EN_OFFSET;
297 	tco_res[1].end = tco_res[1].start + SMI_EN_SIZE - 1;
298 
299 	return 0;
300 }
301 
302 static int intel_pmc_get_resources(struct platform_device *pdev,
303 				   struct intel_pmc_dev *pmc,
304 				   struct intel_scu_ipc_data *scu_data)
305 {
306 	struct resource gcr_res;
307 	size_t npunit_res = 0;
308 	struct resource *res;
309 	int ret;
310 
311 	scu_data->irq = platform_get_irq_optional(pdev, 0);
312 
313 	res = platform_get_resource(pdev, IORESOURCE_MEM,
314 				    PLAT_RESOURCE_IPC_INDEX);
315 	if (!res) {
316 		dev_err(&pdev->dev, "Failed to get IPC resource\n");
317 		return -EINVAL;
318 	}
319 
320 	/* IPC registers */
321 	scu_data->mem.flags = res->flags;
322 	scu_data->mem.start = res->start;
323 	scu_data->mem.end = res->start + PLAT_RESOURCE_IPC_SIZE - 1;
324 
325 	/* GCR registers */
326 	gcr_res.flags = res->flags;
327 	gcr_res.start = res->start + PLAT_RESOURCE_GCR_OFFSET;
328 	gcr_res.end = gcr_res.start + PLAT_RESOURCE_GCR_SIZE - 1;
329 
330 	pmc->gcr_mem_base = devm_ioremap_resource(&pdev->dev, &gcr_res);
331 	if (IS_ERR(pmc->gcr_mem_base))
332 		return PTR_ERR(pmc->gcr_mem_base);
333 
334 	/* Only register iTCO watchdog if there is no WDAT ACPI table */
335 	ret = intel_pmc_get_tco_resources(pdev);
336 	if (ret)
337 		return ret;
338 
339 	/* BIOS data register */
340 	res = platform_get_resource(pdev, IORESOURCE_MEM,
341 				    PLAT_RESOURCE_BIOS_DATA_INDEX);
342 	if (!res) {
343 		dev_err(&pdev->dev, "Failed to get resource of P-unit BIOS data\n");
344 		return -EINVAL;
345 	}
346 	punit_res[npunit_res++] = *res;
347 
348 	/* BIOS interface register */
349 	res = platform_get_resource(pdev, IORESOURCE_MEM,
350 				    PLAT_RESOURCE_BIOS_IFACE_INDEX);
351 	if (!res) {
352 		dev_err(&pdev->dev, "Failed to get resource of P-unit BIOS interface\n");
353 		return -EINVAL;
354 	}
355 	punit_res[npunit_res++] = *res;
356 
357 	/* ISP data register, optional */
358 	res = platform_get_resource(pdev, IORESOURCE_MEM,
359 				    PLAT_RESOURCE_ISP_DATA_INDEX);
360 	if (res)
361 		punit_res[npunit_res++] = *res;
362 
363 	/* ISP interface register, optional */
364 	res = platform_get_resource(pdev, IORESOURCE_MEM,
365 				    PLAT_RESOURCE_ISP_IFACE_INDEX);
366 	if (res)
367 		punit_res[npunit_res++] = *res;
368 
369 	/* GTD data register, optional */
370 	res = platform_get_resource(pdev, IORESOURCE_MEM,
371 				    PLAT_RESOURCE_GTD_DATA_INDEX);
372 	if (res)
373 		punit_res[npunit_res++] = *res;
374 
375 	/* GTD interface register, optional */
376 	res = platform_get_resource(pdev, IORESOURCE_MEM,
377 				    PLAT_RESOURCE_GTD_IFACE_INDEX);
378 	if (res)
379 		punit_res[npunit_res++] = *res;
380 
381 	punit.num_resources = npunit_res;
382 
383 	/* Telemetry SSRAM is optional */
384 	res = platform_get_resource(pdev, IORESOURCE_MEM,
385 				    PLAT_RESOURCE_TELEM_SSRAM_INDEX);
386 	if (res)
387 		pmc->telem_base = res;
388 
389 	return 0;
390 }
391 
392 static int intel_pmc_create_devices(struct intel_pmc_dev *pmc)
393 {
394 	int ret;
395 
396 	if (!acpi_has_watchdog()) {
397 		ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO, &tco,
398 					   1, NULL, 0, NULL);
399 		if (ret)
400 			return ret;
401 	}
402 
403 	ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO, &punit, 1,
404 				   NULL, 0, NULL);
405 	if (ret)
406 		return ret;
407 
408 	if (pmc->telem_base) {
409 		ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO,
410 					   &telem, 1, pmc->telem_base, 0, NULL);
411 	}
412 
413 	return ret;
414 }
415 
416 static const struct acpi_device_id intel_pmc_acpi_ids[] = {
417 	{ "INT34D2" },
418 	{ }
419 };
420 MODULE_DEVICE_TABLE(acpi, intel_pmc_acpi_ids);
421 
422 static int intel_pmc_probe(struct platform_device *pdev)
423 {
424 	struct intel_scu_ipc_data scu_data = {};
425 	struct intel_pmc_dev *pmc;
426 	int ret;
427 
428 	pmc = devm_kzalloc(&pdev->dev, sizeof(*pmc), GFP_KERNEL);
429 	if (!pmc)
430 		return -ENOMEM;
431 
432 	pmc->dev = &pdev->dev;
433 	spin_lock_init(&pmc->gcr_lock);
434 
435 	ret = intel_pmc_get_resources(pdev, pmc, &scu_data);
436 	if (ret) {
437 		dev_err(&pdev->dev, "Failed to request resources\n");
438 		return ret;
439 	}
440 
441 	pmc->scu = devm_intel_scu_ipc_register(&pdev->dev, &scu_data);
442 	if (IS_ERR(pmc->scu))
443 		return PTR_ERR(pmc->scu);
444 
445 	platform_set_drvdata(pdev, pmc);
446 
447 	ret = intel_pmc_create_devices(pmc);
448 	if (ret)
449 		dev_err(&pdev->dev, "Failed to create PMC devices\n");
450 
451 	return ret;
452 }
453 
454 static struct platform_driver intel_pmc_driver = {
455 	.probe = intel_pmc_probe,
456 	.driver = {
457 		.name = "intel_pmc_bxt",
458 		.acpi_match_table = intel_pmc_acpi_ids,
459 		.dev_groups = intel_pmc_groups,
460 	},
461 };
462 module_platform_driver(intel_pmc_driver);
463 
464 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
465 MODULE_AUTHOR("Zha Qipeng <qipeng.zha@intel.com>");
466 MODULE_DESCRIPTION("Intel Broxton PMC driver");
467 MODULE_LICENSE("GPL v2");
468