1 /* 2 * ACPI support for Intel Lynxpoint LPSS. 3 * 4 * Copyright (C) 2013, Intel Corporation 5 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> 6 * Rafael J. Wysocki <rafael.j.wysocki@intel.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/acpi.h> 14 #include <linux/clkdev.h> 15 #include <linux/clk-provider.h> 16 #include <linux/err.h> 17 #include <linux/io.h> 18 #include <linux/mutex.h> 19 #include <linux/platform_device.h> 20 #include <linux/platform_data/clk-lpss.h> 21 #include <linux/pm_domain.h> 22 #include <linux/pm_runtime.h> 23 #include <linux/delay.h> 24 25 #include "internal.h" 26 27 ACPI_MODULE_NAME("acpi_lpss"); 28 29 #ifdef CONFIG_X86_INTEL_LPSS 30 31 #include <asm/cpu_device_id.h> 32 #include <asm/intel-family.h> 33 #include <asm/iosf_mbi.h> 34 #include <asm/pmc_atom.h> 35 36 #define LPSS_ADDR(desc) ((unsigned long)&desc) 37 38 #define LPSS_CLK_SIZE 0x04 39 #define LPSS_LTR_SIZE 0x18 40 41 /* Offsets relative to LPSS_PRIVATE_OFFSET */ 42 #define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16)) 43 #define LPSS_RESETS 0x04 44 #define LPSS_RESETS_RESET_FUNC BIT(0) 45 #define LPSS_RESETS_RESET_APB BIT(1) 46 #define LPSS_GENERAL 0x08 47 #define LPSS_GENERAL_LTR_MODE_SW BIT(2) 48 #define LPSS_GENERAL_UART_RTS_OVRD BIT(3) 49 #define LPSS_SW_LTR 0x10 50 #define LPSS_AUTO_LTR 0x14 51 #define LPSS_LTR_SNOOP_REQ BIT(15) 52 #define LPSS_LTR_SNOOP_MASK 0x0000FFFF 53 #define LPSS_LTR_SNOOP_LAT_1US 0x800 54 #define LPSS_LTR_SNOOP_LAT_32US 0xC00 55 #define LPSS_LTR_SNOOP_LAT_SHIFT 5 56 #define LPSS_LTR_SNOOP_LAT_CUTOFF 3000 57 #define LPSS_LTR_MAX_VAL 0x3FF 58 #define LPSS_TX_INT 0x20 59 #define LPSS_TX_INT_MASK BIT(1) 60 61 #define LPSS_PRV_REG_COUNT 9 62 63 /* LPSS Flags */ 64 #define LPSS_CLK BIT(0) 65 #define LPSS_CLK_GATE BIT(1) 66 #define LPSS_CLK_DIVIDER BIT(2) 67 #define LPSS_LTR BIT(3) 68 #define LPSS_SAVE_CTX BIT(4) 69 #define LPSS_NO_D3_DELAY BIT(5) 70 71 struct lpss_private_data; 72 73 struct lpss_device_desc { 74 unsigned int flags; 75 const char *clk_con_id; 76 unsigned int prv_offset; 77 size_t prv_size_override; 78 struct property_entry *properties; 79 void (*setup)(struct lpss_private_data *pdata); 80 }; 81 82 static const struct lpss_device_desc lpss_dma_desc = { 83 .flags = LPSS_CLK, 84 }; 85 86 struct lpss_private_data { 87 void __iomem *mmio_base; 88 resource_size_t mmio_size; 89 unsigned int fixed_clk_rate; 90 struct clk *clk; 91 const struct lpss_device_desc *dev_desc; 92 u32 prv_reg_ctx[LPSS_PRV_REG_COUNT]; 93 }; 94 95 /* LPSS run time quirks */ 96 static unsigned int lpss_quirks; 97 98 /* 99 * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device. 100 * 101 * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover 102 * it can be powered off automatically whenever the last LPSS device goes down. 103 * In case of no power any access to the DMA controller will hang the system. 104 * The behaviour is reproduced on some HP laptops based on Intel BayTrail as 105 * well as on ASuS T100TA transformer. 106 * 107 * This quirk overrides power state of entire LPSS island to keep DMA powered 108 * on whenever we have at least one other device in use. 109 */ 110 #define LPSS_QUIRK_ALWAYS_POWER_ON BIT(0) 111 112 /* UART Component Parameter Register */ 113 #define LPSS_UART_CPR 0xF4 114 #define LPSS_UART_CPR_AFCE BIT(4) 115 116 static void lpss_uart_setup(struct lpss_private_data *pdata) 117 { 118 unsigned int offset; 119 u32 val; 120 121 offset = pdata->dev_desc->prv_offset + LPSS_TX_INT; 122 val = readl(pdata->mmio_base + offset); 123 writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset); 124 125 val = readl(pdata->mmio_base + LPSS_UART_CPR); 126 if (!(val & LPSS_UART_CPR_AFCE)) { 127 offset = pdata->dev_desc->prv_offset + LPSS_GENERAL; 128 val = readl(pdata->mmio_base + offset); 129 val |= LPSS_GENERAL_UART_RTS_OVRD; 130 writel(val, pdata->mmio_base + offset); 131 } 132 } 133 134 static void lpss_deassert_reset(struct lpss_private_data *pdata) 135 { 136 unsigned int offset; 137 u32 val; 138 139 offset = pdata->dev_desc->prv_offset + LPSS_RESETS; 140 val = readl(pdata->mmio_base + offset); 141 val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC; 142 writel(val, pdata->mmio_base + offset); 143 } 144 145 #define LPSS_I2C_ENABLE 0x6c 146 147 static void byt_i2c_setup(struct lpss_private_data *pdata) 148 { 149 lpss_deassert_reset(pdata); 150 151 if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset)) 152 pdata->fixed_clk_rate = 133000000; 153 154 writel(0, pdata->mmio_base + LPSS_I2C_ENABLE); 155 } 156 157 static const struct lpss_device_desc lpt_dev_desc = { 158 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR, 159 .prv_offset = 0x800, 160 }; 161 162 static const struct lpss_device_desc lpt_i2c_dev_desc = { 163 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR, 164 .prv_offset = 0x800, 165 }; 166 167 static struct property_entry uart_properties[] = { 168 PROPERTY_ENTRY_U32("reg-io-width", 4), 169 PROPERTY_ENTRY_U32("reg-shift", 2), 170 PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"), 171 { }, 172 }; 173 174 static const struct lpss_device_desc lpt_uart_dev_desc = { 175 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR, 176 .clk_con_id = "baudclk", 177 .prv_offset = 0x800, 178 .setup = lpss_uart_setup, 179 .properties = uart_properties, 180 }; 181 182 static const struct lpss_device_desc lpt_sdio_dev_desc = { 183 .flags = LPSS_LTR, 184 .prv_offset = 0x1000, 185 .prv_size_override = 0x1018, 186 }; 187 188 static const struct lpss_device_desc byt_pwm_dev_desc = { 189 .flags = LPSS_SAVE_CTX, 190 }; 191 192 static const struct lpss_device_desc bsw_pwm_dev_desc = { 193 .flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY, 194 }; 195 196 static const struct lpss_device_desc byt_uart_dev_desc = { 197 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX, 198 .clk_con_id = "baudclk", 199 .prv_offset = 0x800, 200 .setup = lpss_uart_setup, 201 .properties = uart_properties, 202 }; 203 204 static const struct lpss_device_desc bsw_uart_dev_desc = { 205 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX 206 | LPSS_NO_D3_DELAY, 207 .clk_con_id = "baudclk", 208 .prv_offset = 0x800, 209 .setup = lpss_uart_setup, 210 .properties = uart_properties, 211 }; 212 213 static const struct lpss_device_desc byt_spi_dev_desc = { 214 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX, 215 .prv_offset = 0x400, 216 }; 217 218 static const struct lpss_device_desc byt_sdio_dev_desc = { 219 .flags = LPSS_CLK, 220 }; 221 222 static const struct lpss_device_desc byt_i2c_dev_desc = { 223 .flags = LPSS_CLK | LPSS_SAVE_CTX, 224 .prv_offset = 0x800, 225 .setup = byt_i2c_setup, 226 }; 227 228 static const struct lpss_device_desc bsw_i2c_dev_desc = { 229 .flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY, 230 .prv_offset = 0x800, 231 .setup = byt_i2c_setup, 232 }; 233 234 static const struct lpss_device_desc bsw_spi_dev_desc = { 235 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX 236 | LPSS_NO_D3_DELAY, 237 .prv_offset = 0x400, 238 .setup = lpss_deassert_reset, 239 }; 240 241 #define ICPU(model) { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, } 242 243 static const struct x86_cpu_id lpss_cpu_ids[] = { 244 ICPU(INTEL_FAM6_ATOM_SILVERMONT1), /* Valleyview, Bay Trail */ 245 ICPU(INTEL_FAM6_ATOM_AIRMONT), /* Braswell, Cherry Trail */ 246 {} 247 }; 248 249 #else 250 251 #define LPSS_ADDR(desc) (0UL) 252 253 #endif /* CONFIG_X86_INTEL_LPSS */ 254 255 static const struct acpi_device_id acpi_lpss_device_ids[] = { 256 /* Generic LPSS devices */ 257 { "INTL9C60", LPSS_ADDR(lpss_dma_desc) }, 258 259 /* Lynxpoint LPSS devices */ 260 { "INT33C0", LPSS_ADDR(lpt_dev_desc) }, 261 { "INT33C1", LPSS_ADDR(lpt_dev_desc) }, 262 { "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) }, 263 { "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) }, 264 { "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) }, 265 { "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) }, 266 { "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) }, 267 { "INT33C7", }, 268 269 /* BayTrail LPSS devices */ 270 { "80860F09", LPSS_ADDR(byt_pwm_dev_desc) }, 271 { "80860F0A", LPSS_ADDR(byt_uart_dev_desc) }, 272 { "80860F0E", LPSS_ADDR(byt_spi_dev_desc) }, 273 { "80860F14", LPSS_ADDR(byt_sdio_dev_desc) }, 274 { "80860F41", LPSS_ADDR(byt_i2c_dev_desc) }, 275 { "INT33B2", }, 276 { "INT33FC", }, 277 278 /* Braswell LPSS devices */ 279 { "80862288", LPSS_ADDR(bsw_pwm_dev_desc) }, 280 { "8086228A", LPSS_ADDR(bsw_uart_dev_desc) }, 281 { "8086228E", LPSS_ADDR(bsw_spi_dev_desc) }, 282 { "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) }, 283 284 /* Broadwell LPSS devices */ 285 { "INT3430", LPSS_ADDR(lpt_dev_desc) }, 286 { "INT3431", LPSS_ADDR(lpt_dev_desc) }, 287 { "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) }, 288 { "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) }, 289 { "INT3434", LPSS_ADDR(lpt_uart_dev_desc) }, 290 { "INT3435", LPSS_ADDR(lpt_uart_dev_desc) }, 291 { "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) }, 292 { "INT3437", }, 293 294 /* Wildcat Point LPSS devices */ 295 { "INT3438", LPSS_ADDR(lpt_dev_desc) }, 296 297 { } 298 }; 299 300 #ifdef CONFIG_X86_INTEL_LPSS 301 302 static int is_memory(struct acpi_resource *res, void *not_used) 303 { 304 struct resource r; 305 return !acpi_dev_resource_memory(res, &r); 306 } 307 308 /* LPSS main clock device. */ 309 static struct platform_device *lpss_clk_dev; 310 311 static inline void lpt_register_clock_device(void) 312 { 313 lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0); 314 } 315 316 static int register_device_clock(struct acpi_device *adev, 317 struct lpss_private_data *pdata) 318 { 319 const struct lpss_device_desc *dev_desc = pdata->dev_desc; 320 const char *devname = dev_name(&adev->dev); 321 struct clk *clk = ERR_PTR(-ENODEV); 322 struct lpss_clk_data *clk_data; 323 const char *parent, *clk_name; 324 void __iomem *prv_base; 325 326 if (!lpss_clk_dev) 327 lpt_register_clock_device(); 328 329 clk_data = platform_get_drvdata(lpss_clk_dev); 330 if (!clk_data) 331 return -ENODEV; 332 clk = clk_data->clk; 333 334 if (!pdata->mmio_base 335 || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE) 336 return -ENODATA; 337 338 parent = clk_data->name; 339 prv_base = pdata->mmio_base + dev_desc->prv_offset; 340 341 if (pdata->fixed_clk_rate) { 342 clk = clk_register_fixed_rate(NULL, devname, parent, 0, 343 pdata->fixed_clk_rate); 344 goto out; 345 } 346 347 if (dev_desc->flags & LPSS_CLK_GATE) { 348 clk = clk_register_gate(NULL, devname, parent, 0, 349 prv_base, 0, 0, NULL); 350 parent = devname; 351 } 352 353 if (dev_desc->flags & LPSS_CLK_DIVIDER) { 354 /* Prevent division by zero */ 355 if (!readl(prv_base)) 356 writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base); 357 358 clk_name = kasprintf(GFP_KERNEL, "%s-div", devname); 359 if (!clk_name) 360 return -ENOMEM; 361 clk = clk_register_fractional_divider(NULL, clk_name, parent, 362 0, prv_base, 363 1, 15, 16, 15, 0, NULL); 364 parent = clk_name; 365 366 clk_name = kasprintf(GFP_KERNEL, "%s-update", devname); 367 if (!clk_name) { 368 kfree(parent); 369 return -ENOMEM; 370 } 371 clk = clk_register_gate(NULL, clk_name, parent, 372 CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE, 373 prv_base, 31, 0, NULL); 374 kfree(parent); 375 kfree(clk_name); 376 } 377 out: 378 if (IS_ERR(clk)) 379 return PTR_ERR(clk); 380 381 pdata->clk = clk; 382 clk_register_clkdev(clk, dev_desc->clk_con_id, devname); 383 return 0; 384 } 385 386 static int acpi_lpss_create_device(struct acpi_device *adev, 387 const struct acpi_device_id *id) 388 { 389 const struct lpss_device_desc *dev_desc; 390 struct lpss_private_data *pdata; 391 struct resource_entry *rentry; 392 struct list_head resource_list; 393 struct platform_device *pdev; 394 int ret; 395 396 dev_desc = (const struct lpss_device_desc *)id->driver_data; 397 if (!dev_desc) { 398 pdev = acpi_create_platform_device(adev); 399 return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1; 400 } 401 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); 402 if (!pdata) 403 return -ENOMEM; 404 405 INIT_LIST_HEAD(&resource_list); 406 ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL); 407 if (ret < 0) 408 goto err_out; 409 410 list_for_each_entry(rentry, &resource_list, node) 411 if (resource_type(rentry->res) == IORESOURCE_MEM) { 412 if (dev_desc->prv_size_override) 413 pdata->mmio_size = dev_desc->prv_size_override; 414 else 415 pdata->mmio_size = resource_size(rentry->res); 416 pdata->mmio_base = ioremap(rentry->res->start, 417 pdata->mmio_size); 418 break; 419 } 420 421 acpi_dev_free_resource_list(&resource_list); 422 423 if (!pdata->mmio_base) { 424 ret = -ENOMEM; 425 goto err_out; 426 } 427 428 pdata->dev_desc = dev_desc; 429 430 if (dev_desc->setup) 431 dev_desc->setup(pdata); 432 433 if (dev_desc->flags & LPSS_CLK) { 434 ret = register_device_clock(adev, pdata); 435 if (ret) { 436 /* Skip the device, but continue the namespace scan. */ 437 ret = 0; 438 goto err_out; 439 } 440 } 441 442 /* 443 * This works around a known issue in ACPI tables where LPSS devices 444 * have _PS0 and _PS3 without _PSC (and no power resources), so 445 * acpi_bus_init_power() will assume that the BIOS has put them into D0. 446 */ 447 ret = acpi_device_fix_up_power(adev); 448 if (ret) { 449 /* Skip the device, but continue the namespace scan. */ 450 ret = 0; 451 goto err_out; 452 } 453 454 if (dev_desc->properties) { 455 ret = device_add_properties(&adev->dev, dev_desc->properties); 456 if (ret) 457 goto err_out; 458 } 459 460 adev->driver_data = pdata; 461 pdev = acpi_create_platform_device(adev); 462 if (!IS_ERR_OR_NULL(pdev)) { 463 return 1; 464 } 465 466 ret = PTR_ERR(pdev); 467 adev->driver_data = NULL; 468 469 err_out: 470 kfree(pdata); 471 return ret; 472 } 473 474 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg) 475 { 476 return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg); 477 } 478 479 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata, 480 unsigned int reg) 481 { 482 writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg); 483 } 484 485 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val) 486 { 487 struct acpi_device *adev; 488 struct lpss_private_data *pdata; 489 unsigned long flags; 490 int ret; 491 492 ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev); 493 if (WARN_ON(ret)) 494 return ret; 495 496 spin_lock_irqsave(&dev->power.lock, flags); 497 if (pm_runtime_suspended(dev)) { 498 ret = -EAGAIN; 499 goto out; 500 } 501 pdata = acpi_driver_data(adev); 502 if (WARN_ON(!pdata || !pdata->mmio_base)) { 503 ret = -ENODEV; 504 goto out; 505 } 506 *val = __lpss_reg_read(pdata, reg); 507 508 out: 509 spin_unlock_irqrestore(&dev->power.lock, flags); 510 return ret; 511 } 512 513 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr, 514 char *buf) 515 { 516 u32 ltr_value = 0; 517 unsigned int reg; 518 int ret; 519 520 reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR; 521 ret = lpss_reg_read(dev, reg, <r_value); 522 if (ret) 523 return ret; 524 525 return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value); 526 } 527 528 static ssize_t lpss_ltr_mode_show(struct device *dev, 529 struct device_attribute *attr, char *buf) 530 { 531 u32 ltr_mode = 0; 532 char *outstr; 533 int ret; 534 535 ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode); 536 if (ret) 537 return ret; 538 539 outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto"; 540 return sprintf(buf, "%s\n", outstr); 541 } 542 543 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL); 544 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL); 545 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL); 546 547 static struct attribute *lpss_attrs[] = { 548 &dev_attr_auto_ltr.attr, 549 &dev_attr_sw_ltr.attr, 550 &dev_attr_ltr_mode.attr, 551 NULL, 552 }; 553 554 static struct attribute_group lpss_attr_group = { 555 .attrs = lpss_attrs, 556 .name = "lpss_ltr", 557 }; 558 559 static void acpi_lpss_set_ltr(struct device *dev, s32 val) 560 { 561 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 562 u32 ltr_mode, ltr_val; 563 564 ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL); 565 if (val < 0) { 566 if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) { 567 ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW; 568 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); 569 } 570 return; 571 } 572 ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK; 573 if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) { 574 ltr_val |= LPSS_LTR_SNOOP_LAT_32US; 575 val = LPSS_LTR_MAX_VAL; 576 } else if (val > LPSS_LTR_MAX_VAL) { 577 ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ; 578 val >>= LPSS_LTR_SNOOP_LAT_SHIFT; 579 } else { 580 ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ; 581 } 582 ltr_val |= val; 583 __lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR); 584 if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) { 585 ltr_mode |= LPSS_GENERAL_LTR_MODE_SW; 586 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); 587 } 588 } 589 590 #ifdef CONFIG_PM 591 /** 592 * acpi_lpss_save_ctx() - Save the private registers of LPSS device 593 * @dev: LPSS device 594 * @pdata: pointer to the private data of the LPSS device 595 * 596 * Most LPSS devices have private registers which may loose their context when 597 * the device is powered down. acpi_lpss_save_ctx() saves those registers into 598 * prv_reg_ctx array. 599 */ 600 static void acpi_lpss_save_ctx(struct device *dev, 601 struct lpss_private_data *pdata) 602 { 603 unsigned int i; 604 605 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { 606 unsigned long offset = i * sizeof(u32); 607 608 pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset); 609 dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n", 610 pdata->prv_reg_ctx[i], offset); 611 } 612 } 613 614 /** 615 * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device 616 * @dev: LPSS device 617 * @pdata: pointer to the private data of the LPSS device 618 * 619 * Restores the registers that were previously stored with acpi_lpss_save_ctx(). 620 */ 621 static void acpi_lpss_restore_ctx(struct device *dev, 622 struct lpss_private_data *pdata) 623 { 624 unsigned int i; 625 626 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { 627 unsigned long offset = i * sizeof(u32); 628 629 __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset); 630 dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n", 631 pdata->prv_reg_ctx[i], offset); 632 } 633 } 634 635 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata) 636 { 637 /* 638 * The following delay is needed or the subsequent write operations may 639 * fail. The LPSS devices are actually PCI devices and the PCI spec 640 * expects 10ms delay before the device can be accessed after D3 to D0 641 * transition. However some platforms like BSW does not need this delay. 642 */ 643 unsigned int delay = 10; /* default 10ms delay */ 644 645 if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY) 646 delay = 0; 647 648 msleep(delay); 649 } 650 651 static int acpi_lpss_activate(struct device *dev) 652 { 653 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 654 int ret; 655 656 ret = acpi_dev_runtime_resume(dev); 657 if (ret) 658 return ret; 659 660 acpi_lpss_d3_to_d0_delay(pdata); 661 662 /* 663 * This is called only on ->probe() stage where a device is either in 664 * known state defined by BIOS or most likely powered off. Due to this 665 * we have to deassert reset line to be sure that ->probe() will 666 * recognize the device. 667 */ 668 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 669 lpss_deassert_reset(pdata); 670 671 return 0; 672 } 673 674 static void acpi_lpss_dismiss(struct device *dev) 675 { 676 acpi_dev_runtime_suspend(dev); 677 } 678 679 #ifdef CONFIG_PM_SLEEP 680 static int acpi_lpss_suspend_late(struct device *dev) 681 { 682 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 683 int ret; 684 685 ret = pm_generic_suspend_late(dev); 686 if (ret) 687 return ret; 688 689 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 690 acpi_lpss_save_ctx(dev, pdata); 691 692 return acpi_dev_suspend_late(dev); 693 } 694 695 static int acpi_lpss_resume_early(struct device *dev) 696 { 697 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 698 int ret; 699 700 ret = acpi_dev_resume_early(dev); 701 if (ret) 702 return ret; 703 704 acpi_lpss_d3_to_d0_delay(pdata); 705 706 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 707 acpi_lpss_restore_ctx(dev, pdata); 708 709 return pm_generic_resume_early(dev); 710 } 711 #endif /* CONFIG_PM_SLEEP */ 712 713 /* IOSF SB for LPSS island */ 714 #define LPSS_IOSF_UNIT_LPIOEP 0xA0 715 #define LPSS_IOSF_UNIT_LPIO1 0xAB 716 #define LPSS_IOSF_UNIT_LPIO2 0xAC 717 718 #define LPSS_IOSF_PMCSR 0x84 719 #define LPSS_PMCSR_D0 0 720 #define LPSS_PMCSR_D3hot 3 721 #define LPSS_PMCSR_Dx_MASK GENMASK(1, 0) 722 723 #define LPSS_IOSF_GPIODEF0 0x154 724 #define LPSS_GPIODEF0_DMA1_D3 BIT(2) 725 #define LPSS_GPIODEF0_DMA2_D3 BIT(3) 726 #define LPSS_GPIODEF0_DMA_D3_MASK GENMASK(3, 2) 727 728 static DEFINE_MUTEX(lpss_iosf_mutex); 729 730 static void lpss_iosf_enter_d3_state(void) 731 { 732 u32 value1 = 0; 733 u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK; 734 u32 value2 = LPSS_PMCSR_D3hot; 735 u32 mask2 = LPSS_PMCSR_Dx_MASK; 736 /* 737 * PMC provides an information about actual status of the LPSS devices. 738 * Here we read the values related to LPSS power island, i.e. LPSS 739 * devices, excluding both LPSS DMA controllers, along with SCC domain. 740 */ 741 u32 func_dis, d3_sts_0, pmc_status, pmc_mask = 0xfe000ffe; 742 int ret; 743 744 ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis); 745 if (ret) 746 return; 747 748 mutex_lock(&lpss_iosf_mutex); 749 750 ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0); 751 if (ret) 752 goto exit; 753 754 /* 755 * Get the status of entire LPSS power island per device basis. 756 * Shutdown both LPSS DMA controllers if and only if all other devices 757 * are already in D3hot. 758 */ 759 pmc_status = (~(d3_sts_0 | func_dis)) & pmc_mask; 760 if (pmc_status) 761 goto exit; 762 763 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE, 764 LPSS_IOSF_PMCSR, value2, mask2); 765 766 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE, 767 LPSS_IOSF_PMCSR, value2, mask2); 768 769 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE, 770 LPSS_IOSF_GPIODEF0, value1, mask1); 771 exit: 772 mutex_unlock(&lpss_iosf_mutex); 773 } 774 775 static void lpss_iosf_exit_d3_state(void) 776 { 777 u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3; 778 u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK; 779 u32 value2 = LPSS_PMCSR_D0; 780 u32 mask2 = LPSS_PMCSR_Dx_MASK; 781 782 mutex_lock(&lpss_iosf_mutex); 783 784 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE, 785 LPSS_IOSF_GPIODEF0, value1, mask1); 786 787 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE, 788 LPSS_IOSF_PMCSR, value2, mask2); 789 790 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE, 791 LPSS_IOSF_PMCSR, value2, mask2); 792 793 mutex_unlock(&lpss_iosf_mutex); 794 } 795 796 static int acpi_lpss_runtime_suspend(struct device *dev) 797 { 798 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 799 int ret; 800 801 ret = pm_generic_runtime_suspend(dev); 802 if (ret) 803 return ret; 804 805 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 806 acpi_lpss_save_ctx(dev, pdata); 807 808 ret = acpi_dev_runtime_suspend(dev); 809 810 /* 811 * This call must be last in the sequence, otherwise PMC will return 812 * wrong status for devices being about to be powered off. See 813 * lpss_iosf_enter_d3_state() for further information. 814 */ 815 if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available()) 816 lpss_iosf_enter_d3_state(); 817 818 return ret; 819 } 820 821 static int acpi_lpss_runtime_resume(struct device *dev) 822 { 823 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 824 int ret; 825 826 /* 827 * This call is kept first to be in symmetry with 828 * acpi_lpss_runtime_suspend() one. 829 */ 830 if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available()) 831 lpss_iosf_exit_d3_state(); 832 833 ret = acpi_dev_runtime_resume(dev); 834 if (ret) 835 return ret; 836 837 acpi_lpss_d3_to_d0_delay(pdata); 838 839 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 840 acpi_lpss_restore_ctx(dev, pdata); 841 842 return pm_generic_runtime_resume(dev); 843 } 844 #endif /* CONFIG_PM */ 845 846 static struct dev_pm_domain acpi_lpss_pm_domain = { 847 #ifdef CONFIG_PM 848 .activate = acpi_lpss_activate, 849 .dismiss = acpi_lpss_dismiss, 850 #endif 851 .ops = { 852 #ifdef CONFIG_PM 853 #ifdef CONFIG_PM_SLEEP 854 .prepare = acpi_subsys_prepare, 855 .complete = pm_complete_with_resume_check, 856 .suspend = acpi_subsys_suspend, 857 .suspend_late = acpi_lpss_suspend_late, 858 .resume_early = acpi_lpss_resume_early, 859 .freeze = acpi_subsys_freeze, 860 .poweroff = acpi_subsys_suspend, 861 .poweroff_late = acpi_lpss_suspend_late, 862 .restore_early = acpi_lpss_resume_early, 863 #endif 864 .runtime_suspend = acpi_lpss_runtime_suspend, 865 .runtime_resume = acpi_lpss_runtime_resume, 866 #endif 867 }, 868 }; 869 870 static int acpi_lpss_platform_notify(struct notifier_block *nb, 871 unsigned long action, void *data) 872 { 873 struct platform_device *pdev = to_platform_device(data); 874 struct lpss_private_data *pdata; 875 struct acpi_device *adev; 876 const struct acpi_device_id *id; 877 878 id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev); 879 if (!id || !id->driver_data) 880 return 0; 881 882 if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) 883 return 0; 884 885 pdata = acpi_driver_data(adev); 886 if (!pdata) 887 return 0; 888 889 if (pdata->mmio_base && 890 pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) { 891 dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n"); 892 return 0; 893 } 894 895 switch (action) { 896 case BUS_NOTIFY_BIND_DRIVER: 897 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain); 898 break; 899 case BUS_NOTIFY_DRIVER_NOT_BOUND: 900 case BUS_NOTIFY_UNBOUND_DRIVER: 901 dev_pm_domain_set(&pdev->dev, NULL); 902 break; 903 case BUS_NOTIFY_ADD_DEVICE: 904 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain); 905 if (pdata->dev_desc->flags & LPSS_LTR) 906 return sysfs_create_group(&pdev->dev.kobj, 907 &lpss_attr_group); 908 break; 909 case BUS_NOTIFY_DEL_DEVICE: 910 if (pdata->dev_desc->flags & LPSS_LTR) 911 sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group); 912 dev_pm_domain_set(&pdev->dev, NULL); 913 break; 914 default: 915 break; 916 } 917 918 return 0; 919 } 920 921 static struct notifier_block acpi_lpss_nb = { 922 .notifier_call = acpi_lpss_platform_notify, 923 }; 924 925 static void acpi_lpss_bind(struct device *dev) 926 { 927 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 928 929 if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR)) 930 return; 931 932 if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) 933 dev->power.set_latency_tolerance = acpi_lpss_set_ltr; 934 else 935 dev_err(dev, "MMIO size insufficient to access LTR\n"); 936 } 937 938 static void acpi_lpss_unbind(struct device *dev) 939 { 940 dev->power.set_latency_tolerance = NULL; 941 } 942 943 static struct acpi_scan_handler lpss_handler = { 944 .ids = acpi_lpss_device_ids, 945 .attach = acpi_lpss_create_device, 946 .bind = acpi_lpss_bind, 947 .unbind = acpi_lpss_unbind, 948 }; 949 950 void __init acpi_lpss_init(void) 951 { 952 const struct x86_cpu_id *id; 953 int ret; 954 955 ret = lpt_clk_init(); 956 if (ret) 957 return; 958 959 id = x86_match_cpu(lpss_cpu_ids); 960 if (id) 961 lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON; 962 963 bus_register_notifier(&platform_bus_type, &acpi_lpss_nb); 964 acpi_scan_add_handler(&lpss_handler); 965 } 966 967 #else 968 969 static struct acpi_scan_handler lpss_handler = { 970 .ids = acpi_lpss_device_ids, 971 }; 972 973 void __init acpi_lpss_init(void) 974 { 975 acpi_scan_add_handler(&lpss_handler); 976 } 977 978 #endif /* CONFIG_X86_INTEL_LPSS */ 979