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
27 #include <asm/intel_scu_ipc.h>
28
29 /* Residency with clock rate at 19.2MHz to usecs */
30 #define S0IX_RESIDENCY_IN_USECS(d, s) \
31 ({ \
32 u64 result = 10ull * ((d) + (s)); \
33 do_div(result, 192); \
34 result; \
35 })
36
37 /* Resources exported from IFWI */
38 #define PLAT_RESOURCE_IPC_INDEX 0
39 #define PLAT_RESOURCE_IPC_SIZE 0x1000
40 #define PLAT_RESOURCE_GCR_OFFSET 0x1000
41 #define PLAT_RESOURCE_GCR_SIZE 0x1000
42 #define PLAT_RESOURCE_BIOS_DATA_INDEX 1
43 #define PLAT_RESOURCE_BIOS_IFACE_INDEX 2
44 #define PLAT_RESOURCE_TELEM_SSRAM_INDEX 3
45 #define PLAT_RESOURCE_ISP_DATA_INDEX 4
46 #define PLAT_RESOURCE_ISP_IFACE_INDEX 5
47 #define PLAT_RESOURCE_GTD_DATA_INDEX 6
48 #define PLAT_RESOURCE_GTD_IFACE_INDEX 7
49 #define PLAT_RESOURCE_ACPI_IO_INDEX 0
50
51 /*
52 * BIOS does not create an ACPI device for each PMC function, but
53 * exports multiple resources from one ACPI device (IPC) for multiple
54 * functions. This driver is responsible for creating a child device and
55 * to export resources for those functions.
56 */
57 #define SMI_EN_OFFSET 0x0040
58 #define SMI_EN_SIZE 4
59 #define TCO_BASE_OFFSET 0x0060
60 #define TCO_REGS_SIZE 16
61 #define TELEM_SSRAM_SIZE 240
62 #define TELEM_PMC_SSRAM_OFFSET 0x1b00
63 #define TELEM_PUNIT_SSRAM_OFFSET 0x1a00
64
65 /* Commands */
66 #define PMC_NORTHPEAK_CTRL 0xed
67
is_gcr_valid(u32 offset)68 static inline bool is_gcr_valid(u32 offset)
69 {
70 return offset < PLAT_RESOURCE_GCR_SIZE - 8;
71 }
72
73 /**
74 * intel_pmc_gcr_read64() - Read a 64-bit PMC GCR register
75 * @pmc: PMC device pointer
76 * @offset: offset of GCR register from GCR address base
77 * @data: data pointer for storing the register output
78 *
79 * Reads the 64-bit PMC GCR register at given offset.
80 *
81 * Return: Negative value on error or 0 on success.
82 */
intel_pmc_gcr_read64(struct intel_pmc_dev * pmc,u32 offset,u64 * data)83 int intel_pmc_gcr_read64(struct intel_pmc_dev *pmc, u32 offset, u64 *data)
84 {
85 if (!is_gcr_valid(offset))
86 return -EINVAL;
87
88 spin_lock(&pmc->gcr_lock);
89 *data = readq(pmc->gcr_mem_base + offset);
90 spin_unlock(&pmc->gcr_lock);
91
92 return 0;
93 }
94 EXPORT_SYMBOL_GPL(intel_pmc_gcr_read64);
95
96 /**
97 * intel_pmc_gcr_update() - Update PMC GCR register bits
98 * @pmc: PMC device pointer
99 * @offset: offset of GCR register from GCR address base
100 * @mask: bit mask for update operation
101 * @val: update value
102 *
103 * Updates the bits of given GCR register as specified by
104 * @mask and @val.
105 *
106 * Return: Negative value on error or 0 on success.
107 */
intel_pmc_gcr_update(struct intel_pmc_dev * pmc,u32 offset,u32 mask,u32 val)108 int intel_pmc_gcr_update(struct intel_pmc_dev *pmc, u32 offset, u32 mask, u32 val)
109 {
110 u32 new_val;
111
112 if (!is_gcr_valid(offset))
113 return -EINVAL;
114
115 spin_lock(&pmc->gcr_lock);
116 new_val = readl(pmc->gcr_mem_base + offset);
117
118 new_val = (new_val & ~mask) | (val & mask);
119 writel(new_val, pmc->gcr_mem_base + offset);
120
121 new_val = readl(pmc->gcr_mem_base + offset);
122 spin_unlock(&pmc->gcr_lock);
123
124 /* Check whether the bit update is successful */
125 return (new_val & mask) != (val & mask) ? -EIO : 0;
126 }
127 EXPORT_SYMBOL_GPL(intel_pmc_gcr_update);
128
129 /**
130 * intel_pmc_s0ix_counter_read() - Read S0ix residency
131 * @pmc: PMC device pointer
132 * @data: Out param that contains current S0ix residency count.
133 *
134 * Writes to @data how many usecs the system has been in low-power S0ix
135 * state.
136 *
137 * Return: An error code or 0 on success.
138 */
intel_pmc_s0ix_counter_read(struct intel_pmc_dev * pmc,u64 * data)139 int intel_pmc_s0ix_counter_read(struct intel_pmc_dev *pmc, u64 *data)
140 {
141 u64 deep, shlw;
142
143 spin_lock(&pmc->gcr_lock);
144 deep = readq(pmc->gcr_mem_base + PMC_GCR_TELEM_DEEP_S0IX_REG);
145 shlw = readq(pmc->gcr_mem_base + PMC_GCR_TELEM_SHLW_S0IX_REG);
146 spin_unlock(&pmc->gcr_lock);
147
148 *data = S0IX_RESIDENCY_IN_USECS(deep, shlw);
149 return 0;
150 }
151 EXPORT_SYMBOL_GPL(intel_pmc_s0ix_counter_read);
152
153 /**
154 * simplecmd_store() - Send a simple IPC command
155 * @dev: Device under the attribute is
156 * @attr: Attribute in question
157 * @buf: Buffer holding data to be stored to the attribute
158 * @count: Number of bytes in @buf
159 *
160 * Expects a string with two integers separated with space. These two
161 * values hold command and subcommand that is send to PMC.
162 *
163 * Return: Number number of bytes written (@count) or negative errno in
164 * case of error.
165 */
simplecmd_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)166 static ssize_t simplecmd_store(struct device *dev, struct device_attribute *attr,
167 const char *buf, size_t count)
168 {
169 struct intel_pmc_dev *pmc = dev_get_drvdata(dev);
170 struct intel_scu_ipc_dev *scu = pmc->scu;
171 int subcmd;
172 int cmd;
173 int ret;
174
175 ret = sscanf(buf, "%d %d", &cmd, &subcmd);
176 if (ret != 2) {
177 dev_err(dev, "Invalid values, expected: cmd subcmd\n");
178 return -EINVAL;
179 }
180
181 ret = intel_scu_ipc_dev_simple_command(scu, cmd, subcmd);
182 if (ret)
183 return ret;
184
185 return count;
186 }
187 static DEVICE_ATTR_WO(simplecmd);
188
189 /**
190 * northpeak_store() - Enable or disable Northpeak
191 * @dev: Device under the attribute is
192 * @attr: Attribute in question
193 * @buf: Buffer holding data to be stored to the attribute
194 * @count: Number of bytes in @buf
195 *
196 * Expects an unsigned integer. Non-zero enables Northpeak and zero
197 * disables it.
198 *
199 * Return: Number number of bytes written (@count) or negative errno in
200 * case of error.
201 */
northpeak_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)202 static ssize_t northpeak_store(struct device *dev, struct device_attribute *attr,
203 const char *buf, size_t count)
204 {
205 struct intel_pmc_dev *pmc = dev_get_drvdata(dev);
206 struct intel_scu_ipc_dev *scu = pmc->scu;
207 unsigned long val;
208 int subcmd;
209 int ret;
210
211 ret = kstrtoul(buf, 0, &val);
212 if (ret)
213 return ret;
214
215 /* Northpeak is enabled if subcmd == 1 and disabled if it is 0 */
216 if (val)
217 subcmd = 1;
218 else
219 subcmd = 0;
220
221 ret = intel_scu_ipc_dev_simple_command(scu, PMC_NORTHPEAK_CTRL, subcmd);
222 if (ret)
223 return ret;
224
225 return count;
226 }
227 static DEVICE_ATTR_WO(northpeak);
228
229 static struct attribute *intel_pmc_attrs[] = {
230 &dev_attr_northpeak.attr,
231 &dev_attr_simplecmd.attr,
232 NULL
233 };
234
235 static const struct attribute_group intel_pmc_group = {
236 .attrs = intel_pmc_attrs,
237 };
238
239 static const struct attribute_group *intel_pmc_groups[] = {
240 &intel_pmc_group,
241 NULL
242 };
243
244 static struct resource punit_res[6];
245
246 static struct mfd_cell punit = {
247 .name = "intel_punit_ipc",
248 .resources = punit_res,
249 };
250
251 static struct itco_wdt_platform_data tco_pdata = {
252 .name = "Apollo Lake SoC",
253 .version = 5,
254 .no_reboot_use_pmc = true,
255 };
256
257 static struct resource tco_res[2];
258
259 static const struct mfd_cell tco = {
260 .name = "iTCO_wdt",
261 .ignore_resource_conflicts = true,
262 .resources = tco_res,
263 .num_resources = ARRAY_SIZE(tco_res),
264 .platform_data = &tco_pdata,
265 .pdata_size = sizeof(tco_pdata),
266 };
267
268 static const struct resource telem_res[] = {
269 DEFINE_RES_MEM(TELEM_PUNIT_SSRAM_OFFSET, TELEM_SSRAM_SIZE),
270 DEFINE_RES_MEM(TELEM_PMC_SSRAM_OFFSET, TELEM_SSRAM_SIZE),
271 };
272
273 static const struct mfd_cell telem = {
274 .name = "intel_telemetry",
275 .resources = telem_res,
276 .num_resources = ARRAY_SIZE(telem_res),
277 };
278
intel_pmc_get_tco_resources(struct platform_device * pdev)279 static int intel_pmc_get_tco_resources(struct platform_device *pdev)
280 {
281 struct resource *res;
282
283 if (acpi_has_watchdog())
284 return 0;
285
286 res = platform_get_resource(pdev, IORESOURCE_IO,
287 PLAT_RESOURCE_ACPI_IO_INDEX);
288 if (!res) {
289 dev_err(&pdev->dev, "Failed to get IO resource\n");
290 return -EINVAL;
291 }
292
293 tco_res[0].flags = IORESOURCE_IO;
294 tco_res[0].start = res->start + TCO_BASE_OFFSET;
295 tco_res[0].end = tco_res[0].start + TCO_REGS_SIZE - 1;
296 tco_res[1].flags = IORESOURCE_IO;
297 tco_res[1].start = res->start + SMI_EN_OFFSET;
298 tco_res[1].end = tco_res[1].start + SMI_EN_SIZE - 1;
299
300 return 0;
301 }
302
intel_pmc_get_resources(struct platform_device * pdev,struct intel_pmc_dev * pmc,struct intel_scu_ipc_data * scu_data)303 static int intel_pmc_get_resources(struct platform_device *pdev,
304 struct intel_pmc_dev *pmc,
305 struct intel_scu_ipc_data *scu_data)
306 {
307 struct resource gcr_res;
308 size_t npunit_res = 0;
309 struct resource *res;
310 int ret;
311
312 scu_data->irq = platform_get_irq_optional(pdev, 0);
313
314 res = platform_get_resource(pdev, IORESOURCE_MEM,
315 PLAT_RESOURCE_IPC_INDEX);
316 if (!res) {
317 dev_err(&pdev->dev, "Failed to get IPC resource\n");
318 return -EINVAL;
319 }
320
321 /* IPC registers */
322 scu_data->mem.flags = res->flags;
323 scu_data->mem.start = res->start;
324 scu_data->mem.end = res->start + PLAT_RESOURCE_IPC_SIZE - 1;
325
326 /* GCR registers */
327 gcr_res.flags = res->flags;
328 gcr_res.start = res->start + PLAT_RESOURCE_GCR_OFFSET;
329 gcr_res.end = gcr_res.start + PLAT_RESOURCE_GCR_SIZE - 1;
330
331 pmc->gcr_mem_base = devm_ioremap_resource(&pdev->dev, &gcr_res);
332 if (IS_ERR(pmc->gcr_mem_base))
333 return PTR_ERR(pmc->gcr_mem_base);
334
335 /* Only register iTCO watchdog if there is no WDAT ACPI table */
336 ret = intel_pmc_get_tco_resources(pdev);
337 if (ret)
338 return ret;
339
340 /* BIOS data register */
341 res = platform_get_resource(pdev, IORESOURCE_MEM,
342 PLAT_RESOURCE_BIOS_DATA_INDEX);
343 if (!res) {
344 dev_err(&pdev->dev, "Failed to get resource of P-unit BIOS data\n");
345 return -EINVAL;
346 }
347 punit_res[npunit_res++] = *res;
348
349 /* BIOS interface register */
350 res = platform_get_resource(pdev, IORESOURCE_MEM,
351 PLAT_RESOURCE_BIOS_IFACE_INDEX);
352 if (!res) {
353 dev_err(&pdev->dev, "Failed to get resource of P-unit BIOS interface\n");
354 return -EINVAL;
355 }
356 punit_res[npunit_res++] = *res;
357
358 /* ISP data register, optional */
359 res = platform_get_resource(pdev, IORESOURCE_MEM,
360 PLAT_RESOURCE_ISP_DATA_INDEX);
361 if (res)
362 punit_res[npunit_res++] = *res;
363
364 /* ISP interface register, optional */
365 res = platform_get_resource(pdev, IORESOURCE_MEM,
366 PLAT_RESOURCE_ISP_IFACE_INDEX);
367 if (res)
368 punit_res[npunit_res++] = *res;
369
370 /* GTD data register, optional */
371 res = platform_get_resource(pdev, IORESOURCE_MEM,
372 PLAT_RESOURCE_GTD_DATA_INDEX);
373 if (res)
374 punit_res[npunit_res++] = *res;
375
376 /* GTD interface register, optional */
377 res = platform_get_resource(pdev, IORESOURCE_MEM,
378 PLAT_RESOURCE_GTD_IFACE_INDEX);
379 if (res)
380 punit_res[npunit_res++] = *res;
381
382 punit.num_resources = npunit_res;
383
384 /* Telemetry SSRAM is optional */
385 res = platform_get_resource(pdev, IORESOURCE_MEM,
386 PLAT_RESOURCE_TELEM_SSRAM_INDEX);
387 if (res)
388 pmc->telem_base = res;
389
390 return 0;
391 }
392
intel_pmc_create_devices(struct intel_pmc_dev * pmc)393 static int intel_pmc_create_devices(struct intel_pmc_dev *pmc)
394 {
395 int ret;
396
397 if (!acpi_has_watchdog()) {
398 ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO, &tco,
399 1, NULL, 0, NULL);
400 if (ret)
401 return ret;
402 }
403
404 ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO, &punit, 1,
405 NULL, 0, NULL);
406 if (ret)
407 return ret;
408
409 if (pmc->telem_base) {
410 ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO,
411 &telem, 1, pmc->telem_base, 0, NULL);
412 }
413
414 return ret;
415 }
416
417 static const struct acpi_device_id intel_pmc_acpi_ids[] = {
418 { "INT34D2" },
419 { }
420 };
421 MODULE_DEVICE_TABLE(acpi, intel_pmc_acpi_ids);
422
intel_pmc_probe(struct platform_device * pdev)423 static int intel_pmc_probe(struct platform_device *pdev)
424 {
425 struct intel_scu_ipc_data scu_data = {};
426 struct intel_pmc_dev *pmc;
427 int ret;
428
429 pmc = devm_kzalloc(&pdev->dev, sizeof(*pmc), GFP_KERNEL);
430 if (!pmc)
431 return -ENOMEM;
432
433 pmc->dev = &pdev->dev;
434 spin_lock_init(&pmc->gcr_lock);
435
436 ret = intel_pmc_get_resources(pdev, pmc, &scu_data);
437 if (ret) {
438 dev_err(&pdev->dev, "Failed to request resources\n");
439 return ret;
440 }
441
442 pmc->scu = devm_intel_scu_ipc_register(&pdev->dev, &scu_data);
443 if (IS_ERR(pmc->scu))
444 return PTR_ERR(pmc->scu);
445
446 platform_set_drvdata(pdev, pmc);
447
448 ret = intel_pmc_create_devices(pmc);
449 if (ret)
450 dev_err(&pdev->dev, "Failed to create PMC devices\n");
451
452 return ret;
453 }
454
455 static struct platform_driver intel_pmc_driver = {
456 .probe = intel_pmc_probe,
457 .driver = {
458 .name = "intel_pmc_bxt",
459 .acpi_match_table = intel_pmc_acpi_ids,
460 .dev_groups = intel_pmc_groups,
461 },
462 };
463 module_platform_driver(intel_pmc_driver);
464
465 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
466 MODULE_AUTHOR("Zha Qipeng <qipeng.zha@intel.com>");
467 MODULE_DESCRIPTION("Intel Broxton PMC driver");
468 MODULE_LICENSE("GPL v2");
469