15f1ae4ebSFu Wei /* 25f1ae4ebSFu Wei * ARM Specific GTDT table Support 35f1ae4ebSFu Wei * 45f1ae4ebSFu Wei * Copyright (C) 2016, Linaro Ltd. 55f1ae4ebSFu Wei * Author: Daniel Lezcano <daniel.lezcano@linaro.org> 65f1ae4ebSFu Wei * Fu Wei <fu.wei@linaro.org> 75f1ae4ebSFu Wei * Hanjun Guo <hanjun.guo@linaro.org> 85f1ae4ebSFu Wei * 95f1ae4ebSFu Wei * This program is free software; you can redistribute it and/or modify 105f1ae4ebSFu Wei * it under the terms of the GNU General Public License version 2 as 115f1ae4ebSFu Wei * published by the Free Software Foundation. 125f1ae4ebSFu Wei */ 135f1ae4ebSFu Wei 145f1ae4ebSFu Wei #include <linux/acpi.h> 155f1ae4ebSFu Wei #include <linux/init.h> 16a712c3edSFu Wei #include <linux/irqdomain.h> 175f1ae4ebSFu Wei #include <linux/kernel.h> 18ca9ae5ecSFu Wei #include <linux/platform_device.h> 195f1ae4ebSFu Wei 205f1ae4ebSFu Wei #include <clocksource/arm_arch_timer.h> 215f1ae4ebSFu Wei 225f1ae4ebSFu Wei #undef pr_fmt 235f1ae4ebSFu Wei #define pr_fmt(fmt) "ACPI GTDT: " fmt 245f1ae4ebSFu Wei 255f1ae4ebSFu Wei /** 265f1ae4ebSFu Wei * struct acpi_gtdt_descriptor - Store the key info of GTDT for all functions 275f1ae4ebSFu Wei * @gtdt: The pointer to the struct acpi_table_gtdt of GTDT table. 285f1ae4ebSFu Wei * @gtdt_end: The pointer to the end of GTDT table. 295f1ae4ebSFu Wei * @platform_timer: The pointer to the start of Platform Timer Structure 305f1ae4ebSFu Wei * 315f1ae4ebSFu Wei * The struct store the key info of GTDT table, it should be initialized by 325f1ae4ebSFu Wei * acpi_gtdt_init. 335f1ae4ebSFu Wei */ 345f1ae4ebSFu Wei struct acpi_gtdt_descriptor { 355f1ae4ebSFu Wei struct acpi_table_gtdt *gtdt; 365f1ae4ebSFu Wei void *gtdt_end; 375f1ae4ebSFu Wei void *platform_timer; 385f1ae4ebSFu Wei }; 395f1ae4ebSFu Wei 405f1ae4ebSFu Wei static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; 415f1ae4ebSFu Wei 42a712c3edSFu Wei static inline void *next_platform_timer(void *platform_timer) 43a712c3edSFu Wei { 44a712c3edSFu Wei struct acpi_gtdt_header *gh = platform_timer; 45a712c3edSFu Wei 46a712c3edSFu Wei platform_timer += gh->length; 47a712c3edSFu Wei if (platform_timer < acpi_gtdt_desc.gtdt_end) 48a712c3edSFu Wei return platform_timer; 49a712c3edSFu Wei 50a712c3edSFu Wei return NULL; 51a712c3edSFu Wei } 52a712c3edSFu Wei 53a712c3edSFu Wei #define for_each_platform_timer(_g) \ 54a712c3edSFu Wei for (_g = acpi_gtdt_desc.platform_timer; _g; \ 55a712c3edSFu Wei _g = next_platform_timer(_g)) 56a712c3edSFu Wei 57a712c3edSFu Wei static inline bool is_timer_block(void *platform_timer) 58a712c3edSFu Wei { 59a712c3edSFu Wei struct acpi_gtdt_header *gh = platform_timer; 60a712c3edSFu Wei 61a712c3edSFu Wei return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK; 62a712c3edSFu Wei } 63a712c3edSFu Wei 64ca9ae5ecSFu Wei static inline bool is_non_secure_watchdog(void *platform_timer) 65ca9ae5ecSFu Wei { 66ca9ae5ecSFu Wei struct acpi_gtdt_header *gh = platform_timer; 67ca9ae5ecSFu Wei struct acpi_gtdt_watchdog *wd = platform_timer; 68ca9ae5ecSFu Wei 69ca9ae5ecSFu Wei if (gh->type != ACPI_GTDT_TYPE_WATCHDOG) 70ca9ae5ecSFu Wei return false; 71ca9ae5ecSFu Wei 72ca9ae5ecSFu Wei return !(wd->timer_flags & ACPI_GTDT_WATCHDOG_SECURE); 73ca9ae5ecSFu Wei } 74ca9ae5ecSFu Wei 755f1ae4ebSFu Wei static int __init map_gt_gsi(u32 interrupt, u32 flags) 765f1ae4ebSFu Wei { 775f1ae4ebSFu Wei int trigger, polarity; 785f1ae4ebSFu Wei 795f1ae4ebSFu Wei trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE 805f1ae4ebSFu Wei : ACPI_LEVEL_SENSITIVE; 815f1ae4ebSFu Wei 825f1ae4ebSFu Wei polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW 835f1ae4ebSFu Wei : ACPI_ACTIVE_HIGH; 845f1ae4ebSFu Wei 855f1ae4ebSFu Wei return acpi_register_gsi(NULL, interrupt, trigger, polarity); 865f1ae4ebSFu Wei } 875f1ae4ebSFu Wei 885f1ae4ebSFu Wei /** 895f1ae4ebSFu Wei * acpi_gtdt_map_ppi() - Map the PPIs of per-cpu arch_timer. 905f1ae4ebSFu Wei * @type: the type of PPI. 915f1ae4ebSFu Wei * 925f1ae4ebSFu Wei * Note: Secure state is not managed by the kernel on ARM64 systems. 935f1ae4ebSFu Wei * So we only handle the non-secure timer PPIs, 945f1ae4ebSFu Wei * ARCH_TIMER_PHYS_SECURE_PPI is treated as invalid type. 955f1ae4ebSFu Wei * 965f1ae4ebSFu Wei * Return: the mapped PPI value, 0 if error. 975f1ae4ebSFu Wei */ 985f1ae4ebSFu Wei int __init acpi_gtdt_map_ppi(int type) 995f1ae4ebSFu Wei { 1005f1ae4ebSFu Wei struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; 1015f1ae4ebSFu Wei 1025f1ae4ebSFu Wei switch (type) { 1035f1ae4ebSFu Wei case ARCH_TIMER_PHYS_NONSECURE_PPI: 1045f1ae4ebSFu Wei return map_gt_gsi(gtdt->non_secure_el1_interrupt, 1055f1ae4ebSFu Wei gtdt->non_secure_el1_flags); 1065f1ae4ebSFu Wei case ARCH_TIMER_VIRT_PPI: 1075f1ae4ebSFu Wei return map_gt_gsi(gtdt->virtual_timer_interrupt, 1085f1ae4ebSFu Wei gtdt->virtual_timer_flags); 1095f1ae4ebSFu Wei 1105f1ae4ebSFu Wei case ARCH_TIMER_HYP_PPI: 1115f1ae4ebSFu Wei return map_gt_gsi(gtdt->non_secure_el2_interrupt, 1125f1ae4ebSFu Wei gtdt->non_secure_el2_flags); 1135f1ae4ebSFu Wei default: 1145f1ae4ebSFu Wei pr_err("Failed to map timer interrupt: invalid type.\n"); 1155f1ae4ebSFu Wei } 1165f1ae4ebSFu Wei 1175f1ae4ebSFu Wei return 0; 1185f1ae4ebSFu Wei } 1195f1ae4ebSFu Wei 1205f1ae4ebSFu Wei /** 1215f1ae4ebSFu Wei * acpi_gtdt_c3stop() - Got c3stop info from GTDT according to the type of PPI. 1225f1ae4ebSFu Wei * @type: the type of PPI. 1235f1ae4ebSFu Wei * 1245f1ae4ebSFu Wei * Return: true if the timer HW state is lost when a CPU enters an idle state, 1255f1ae4ebSFu Wei * false otherwise 1265f1ae4ebSFu Wei */ 1275f1ae4ebSFu Wei bool __init acpi_gtdt_c3stop(int type) 1285f1ae4ebSFu Wei { 1295f1ae4ebSFu Wei struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; 1305f1ae4ebSFu Wei 1315f1ae4ebSFu Wei switch (type) { 1325f1ae4ebSFu Wei case ARCH_TIMER_PHYS_NONSECURE_PPI: 1335f1ae4ebSFu Wei return !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON); 1345f1ae4ebSFu Wei 1355f1ae4ebSFu Wei case ARCH_TIMER_VIRT_PPI: 1365f1ae4ebSFu Wei return !(gtdt->virtual_timer_flags & ACPI_GTDT_ALWAYS_ON); 1375f1ae4ebSFu Wei 1385f1ae4ebSFu Wei case ARCH_TIMER_HYP_PPI: 1395f1ae4ebSFu Wei return !(gtdt->non_secure_el2_flags & ACPI_GTDT_ALWAYS_ON); 1405f1ae4ebSFu Wei 1415f1ae4ebSFu Wei default: 1425f1ae4ebSFu Wei pr_err("Failed to get c3stop info: invalid type.\n"); 1435f1ae4ebSFu Wei } 1445f1ae4ebSFu Wei 1455f1ae4ebSFu Wei return false; 1465f1ae4ebSFu Wei } 1475f1ae4ebSFu Wei 1485f1ae4ebSFu Wei /** 1495f1ae4ebSFu Wei * acpi_gtdt_init() - Get the info of GTDT table to prepare for further init. 1505f1ae4ebSFu Wei * @table: The pointer to GTDT table. 1515f1ae4ebSFu Wei * @platform_timer_count: It points to a integer variable which is used 1525f1ae4ebSFu Wei * for storing the number of platform timers. 1535f1ae4ebSFu Wei * This pointer could be NULL, if the caller 1545f1ae4ebSFu Wei * doesn't need this info. 1555f1ae4ebSFu Wei * 1565f1ae4ebSFu Wei * Return: 0 if success, -EINVAL if error. 1575f1ae4ebSFu Wei */ 1585f1ae4ebSFu Wei int __init acpi_gtdt_init(struct acpi_table_header *table, 1595f1ae4ebSFu Wei int *platform_timer_count) 1605f1ae4ebSFu Wei { 1615f1ae4ebSFu Wei void *platform_timer; 1625f1ae4ebSFu Wei struct acpi_table_gtdt *gtdt; 1635f1ae4ebSFu Wei 1645f1ae4ebSFu Wei gtdt = container_of(table, struct acpi_table_gtdt, header); 1655f1ae4ebSFu Wei acpi_gtdt_desc.gtdt = gtdt; 1665f1ae4ebSFu Wei acpi_gtdt_desc.gtdt_end = (void *)table + table->length; 1675f1ae4ebSFu Wei acpi_gtdt_desc.platform_timer = NULL; 1685f1ae4ebSFu Wei if (platform_timer_count) 1695f1ae4ebSFu Wei *platform_timer_count = 0; 1705f1ae4ebSFu Wei 1715f1ae4ebSFu Wei if (table->revision < 2) { 1725f1ae4ebSFu Wei pr_warn("Revision:%d doesn't support Platform Timers.\n", 1735f1ae4ebSFu Wei table->revision); 1745f1ae4ebSFu Wei return 0; 1755f1ae4ebSFu Wei } 1765f1ae4ebSFu Wei 1775f1ae4ebSFu Wei if (!gtdt->platform_timer_count) { 1785f1ae4ebSFu Wei pr_debug("No Platform Timer.\n"); 1795f1ae4ebSFu Wei return 0; 1805f1ae4ebSFu Wei } 1815f1ae4ebSFu Wei 1825f1ae4ebSFu Wei platform_timer = (void *)gtdt + gtdt->platform_timer_offset; 1835f1ae4ebSFu Wei if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { 1845f1ae4ebSFu Wei pr_err(FW_BUG "invalid timer data.\n"); 1855f1ae4ebSFu Wei return -EINVAL; 1865f1ae4ebSFu Wei } 1875f1ae4ebSFu Wei acpi_gtdt_desc.platform_timer = platform_timer; 1885f1ae4ebSFu Wei if (platform_timer_count) 1895f1ae4ebSFu Wei *platform_timer_count = gtdt->platform_timer_count; 1905f1ae4ebSFu Wei 1915f1ae4ebSFu Wei return 0; 1925f1ae4ebSFu Wei } 193a712c3edSFu Wei 194a712c3edSFu Wei static int __init gtdt_parse_timer_block(struct acpi_gtdt_timer_block *block, 195a712c3edSFu Wei struct arch_timer_mem *timer_mem) 196a712c3edSFu Wei { 197a712c3edSFu Wei int i; 198a712c3edSFu Wei struct arch_timer_mem_frame *frame; 199a712c3edSFu Wei struct acpi_gtdt_timer_entry *gtdt_frame; 200a712c3edSFu Wei 201a712c3edSFu Wei if (!block->timer_count) { 202ee10b9c9SArvind Yadav pr_err(FW_BUG "GT block present, but frame count is zero.\n"); 203a712c3edSFu Wei return -ENODEV; 204a712c3edSFu Wei } 205a712c3edSFu Wei 206a712c3edSFu Wei if (block->timer_count > ARCH_TIMER_MEM_MAX_FRAMES) { 207a712c3edSFu Wei pr_err(FW_BUG "GT block lists %d frames, ACPI spec only allows 8\n", 208a712c3edSFu Wei block->timer_count); 209a712c3edSFu Wei return -EINVAL; 210a712c3edSFu Wei } 211a712c3edSFu Wei 212a712c3edSFu Wei timer_mem->cntctlbase = (phys_addr_t)block->block_address; 213a712c3edSFu Wei /* 214a712c3edSFu Wei * The CNTCTLBase frame is 4KB (register offsets 0x000 - 0xFFC). 215a712c3edSFu Wei * See ARM DDI 0487A.k_iss10775, page I1-5129, Table I1-3 216a712c3edSFu Wei * "CNTCTLBase memory map". 217a712c3edSFu Wei */ 218a712c3edSFu Wei timer_mem->size = SZ_4K; 219a712c3edSFu Wei 220a712c3edSFu Wei gtdt_frame = (void *)block + block->timer_offset; 221a712c3edSFu Wei if (gtdt_frame + block->timer_count != (void *)block + block->header.length) 222a712c3edSFu Wei return -EINVAL; 223a712c3edSFu Wei 224a712c3edSFu Wei /* 225a712c3edSFu Wei * Get the GT timer Frame data for every GT Block Timer 226a712c3edSFu Wei */ 227a712c3edSFu Wei for (i = 0; i < block->timer_count; i++, gtdt_frame++) { 228a712c3edSFu Wei if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER) 229a712c3edSFu Wei continue; 230a712c3edSFu Wei if (gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES || 231a712c3edSFu Wei !gtdt_frame->base_address || !gtdt_frame->timer_interrupt) 232a712c3edSFu Wei goto error; 233a712c3edSFu Wei 234a712c3edSFu Wei frame = &timer_mem->frame[gtdt_frame->frame_number]; 235a712c3edSFu Wei 236a712c3edSFu Wei /* duplicate frame */ 237a712c3edSFu Wei if (frame->valid) 238a712c3edSFu Wei goto error; 239a712c3edSFu Wei 240a712c3edSFu Wei frame->phys_irq = map_gt_gsi(gtdt_frame->timer_interrupt, 241a712c3edSFu Wei gtdt_frame->timer_flags); 242a712c3edSFu Wei if (frame->phys_irq <= 0) { 243a712c3edSFu Wei pr_warn("failed to map physical timer irq in frame %d.\n", 244a712c3edSFu Wei gtdt_frame->frame_number); 245a712c3edSFu Wei goto error; 246a712c3edSFu Wei } 247a712c3edSFu Wei 248a712c3edSFu Wei if (gtdt_frame->virtual_timer_interrupt) { 249a712c3edSFu Wei frame->virt_irq = 250a712c3edSFu Wei map_gt_gsi(gtdt_frame->virtual_timer_interrupt, 251a712c3edSFu Wei gtdt_frame->virtual_timer_flags); 252a712c3edSFu Wei if (frame->virt_irq <= 0) { 253a712c3edSFu Wei pr_warn("failed to map virtual timer irq in frame %d.\n", 254a712c3edSFu Wei gtdt_frame->frame_number); 255a712c3edSFu Wei goto error; 256a712c3edSFu Wei } 257a712c3edSFu Wei } else { 258a712c3edSFu Wei pr_debug("virtual timer in frame %d not implemented.\n", 259a712c3edSFu Wei gtdt_frame->frame_number); 260a712c3edSFu Wei } 261a712c3edSFu Wei 262a712c3edSFu Wei frame->cntbase = gtdt_frame->base_address; 263a712c3edSFu Wei /* 264a712c3edSFu Wei * The CNTBaseN frame is 4KB (register offsets 0x000 - 0xFFC). 265a712c3edSFu Wei * See ARM DDI 0487A.k_iss10775, page I1-5130, Table I1-4 266a712c3edSFu Wei * "CNTBaseN memory map". 267a712c3edSFu Wei */ 268a712c3edSFu Wei frame->size = SZ_4K; 269a712c3edSFu Wei frame->valid = true; 270a712c3edSFu Wei } 271a712c3edSFu Wei 272a712c3edSFu Wei return 0; 273a712c3edSFu Wei 274a712c3edSFu Wei error: 275a712c3edSFu Wei do { 276a712c3edSFu Wei if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER || 277a712c3edSFu Wei gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES) 278a712c3edSFu Wei continue; 279a712c3edSFu Wei 280a712c3edSFu Wei frame = &timer_mem->frame[gtdt_frame->frame_number]; 281a712c3edSFu Wei 282a712c3edSFu Wei if (frame->phys_irq > 0) 283a712c3edSFu Wei acpi_unregister_gsi(gtdt_frame->timer_interrupt); 284a712c3edSFu Wei frame->phys_irq = 0; 285a712c3edSFu Wei 286a712c3edSFu Wei if (frame->virt_irq > 0) 287a712c3edSFu Wei acpi_unregister_gsi(gtdt_frame->virtual_timer_interrupt); 288a712c3edSFu Wei frame->virt_irq = 0; 289a712c3edSFu Wei } while (i-- >= 0 && gtdt_frame--); 290a712c3edSFu Wei 291a712c3edSFu Wei return -EINVAL; 292a712c3edSFu Wei } 293a712c3edSFu Wei 294a712c3edSFu Wei /** 295a712c3edSFu Wei * acpi_arch_timer_mem_init() - Get the info of all GT blocks in GTDT table. 296a712c3edSFu Wei * @timer_mem: The pointer to the array of struct arch_timer_mem for returning 297a712c3edSFu Wei * the result of parsing. The element number of this array should 298a712c3edSFu Wei * be platform_timer_count(the total number of platform timers). 299a712c3edSFu Wei * @timer_count: It points to a integer variable which is used for storing the 300a712c3edSFu Wei * number of GT blocks we have parsed. 301a712c3edSFu Wei * 302a712c3edSFu Wei * Return: 0 if success, -EINVAL/-ENODEV if error. 303a712c3edSFu Wei */ 304a712c3edSFu Wei int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, 305a712c3edSFu Wei int *timer_count) 306a712c3edSFu Wei { 307a712c3edSFu Wei int ret; 308a712c3edSFu Wei void *platform_timer; 309a712c3edSFu Wei 310a712c3edSFu Wei *timer_count = 0; 311a712c3edSFu Wei for_each_platform_timer(platform_timer) { 312a712c3edSFu Wei if (is_timer_block(platform_timer)) { 313a712c3edSFu Wei ret = gtdt_parse_timer_block(platform_timer, timer_mem); 314a712c3edSFu Wei if (ret) 315a712c3edSFu Wei return ret; 316a712c3edSFu Wei timer_mem++; 317a712c3edSFu Wei (*timer_count)++; 318a712c3edSFu Wei } 319a712c3edSFu Wei } 320a712c3edSFu Wei 321a712c3edSFu Wei if (*timer_count) 322a712c3edSFu Wei pr_info("found %d memory-mapped timer block(s).\n", 323a712c3edSFu Wei *timer_count); 324a712c3edSFu Wei 325a712c3edSFu Wei return 0; 326a712c3edSFu Wei } 327ca9ae5ecSFu Wei 328ca9ae5ecSFu Wei /* 329ca9ae5ecSFu Wei * Initialize a SBSA generic Watchdog platform device info from GTDT 330ca9ae5ecSFu Wei */ 331ca9ae5ecSFu Wei static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd, 332ca9ae5ecSFu Wei int index) 333ca9ae5ecSFu Wei { 334ca9ae5ecSFu Wei struct platform_device *pdev; 335ca9ae5ecSFu Wei int irq = map_gt_gsi(wd->timer_interrupt, wd->timer_flags); 336ca9ae5ecSFu Wei 337ca9ae5ecSFu Wei /* 338ca9ae5ecSFu Wei * According to SBSA specification the size of refresh and control 339ca9ae5ecSFu Wei * frames of SBSA Generic Watchdog is SZ_4K(Offset 0x000 – 0xFFF). 340ca9ae5ecSFu Wei */ 341ca9ae5ecSFu Wei struct resource res[] = { 342ca9ae5ecSFu Wei DEFINE_RES_MEM(wd->control_frame_address, SZ_4K), 343ca9ae5ecSFu Wei DEFINE_RES_MEM(wd->refresh_frame_address, SZ_4K), 344ca9ae5ecSFu Wei DEFINE_RES_IRQ(irq), 345ca9ae5ecSFu Wei }; 346ca9ae5ecSFu Wei int nr_res = ARRAY_SIZE(res); 347ca9ae5ecSFu Wei 348ca9ae5ecSFu Wei pr_debug("found a Watchdog (0x%llx/0x%llx gsi:%u flags:0x%x).\n", 349ca9ae5ecSFu Wei wd->refresh_frame_address, wd->control_frame_address, 350ca9ae5ecSFu Wei wd->timer_interrupt, wd->timer_flags); 351ca9ae5ecSFu Wei 352ca9ae5ecSFu Wei if (!(wd->refresh_frame_address && wd->control_frame_address)) { 353ca9ae5ecSFu Wei pr_err(FW_BUG "failed to get the Watchdog base address.\n"); 354ca9ae5ecSFu Wei acpi_unregister_gsi(wd->timer_interrupt); 355ca9ae5ecSFu Wei return -EINVAL; 356ca9ae5ecSFu Wei } 357ca9ae5ecSFu Wei 358ca9ae5ecSFu Wei if (irq <= 0) { 359ca9ae5ecSFu Wei pr_warn("failed to map the Watchdog interrupt.\n"); 360ca9ae5ecSFu Wei nr_res--; 361ca9ae5ecSFu Wei } 362ca9ae5ecSFu Wei 363ca9ae5ecSFu Wei /* 364ca9ae5ecSFu Wei * Add a platform device named "sbsa-gwdt" to match the platform driver. 365ca9ae5ecSFu Wei * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog 366ca9ae5ecSFu Wei * The platform driver can get device info below by matching this name. 367ca9ae5ecSFu Wei */ 368ca9ae5ecSFu Wei pdev = platform_device_register_simple("sbsa-gwdt", index, res, nr_res); 369ca9ae5ecSFu Wei if (IS_ERR(pdev)) { 370ca9ae5ecSFu Wei acpi_unregister_gsi(wd->timer_interrupt); 371ca9ae5ecSFu Wei return PTR_ERR(pdev); 372ca9ae5ecSFu Wei } 373ca9ae5ecSFu Wei 374ca9ae5ecSFu Wei return 0; 375ca9ae5ecSFu Wei } 376ca9ae5ecSFu Wei 377ca9ae5ecSFu Wei static int __init gtdt_sbsa_gwdt_init(void) 378ca9ae5ecSFu Wei { 379ca9ae5ecSFu Wei void *platform_timer; 380ca9ae5ecSFu Wei struct acpi_table_header *table; 381ca9ae5ecSFu Wei int ret, timer_count, gwdt_count = 0; 382ca9ae5ecSFu Wei 383ca9ae5ecSFu Wei if (acpi_disabled) 384ca9ae5ecSFu Wei return 0; 385ca9ae5ecSFu Wei 386ca9ae5ecSFu Wei if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table))) 387ca9ae5ecSFu Wei return -EINVAL; 388ca9ae5ecSFu Wei 389ca9ae5ecSFu Wei /* 390ca9ae5ecSFu Wei * Note: Even though the global variable acpi_gtdt_desc has been 391ca9ae5ecSFu Wei * initialized by acpi_gtdt_init() while initializing the arch timers, 392ca9ae5ecSFu Wei * when we call this function to get SBSA watchdogs info from GTDT, the 393ca9ae5ecSFu Wei * pointers stashed in it are stale (since they are early temporary 394ca9ae5ecSFu Wei * mappings carried out before acpi_permanent_mmap is set) and we need 395ca9ae5ecSFu Wei * to re-initialize them with permanent mapped pointer values to let the 396ca9ae5ecSFu Wei * GTDT parsing possible. 397ca9ae5ecSFu Wei */ 398ca9ae5ecSFu Wei ret = acpi_gtdt_init(table, &timer_count); 399ca9ae5ecSFu Wei if (ret || !timer_count) 400ca9ae5ecSFu Wei return ret; 401ca9ae5ecSFu Wei 402ca9ae5ecSFu Wei for_each_platform_timer(platform_timer) { 403ca9ae5ecSFu Wei if (is_non_secure_watchdog(platform_timer)) { 404ca9ae5ecSFu Wei ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); 405ca9ae5ecSFu Wei if (ret) 406ca9ae5ecSFu Wei break; 407ca9ae5ecSFu Wei gwdt_count++; 408ca9ae5ecSFu Wei } 409ca9ae5ecSFu Wei } 410ca9ae5ecSFu Wei 411ca9ae5ecSFu Wei if (gwdt_count) 412ca9ae5ecSFu Wei pr_info("found %d SBSA generic Watchdog(s).\n", gwdt_count); 413ca9ae5ecSFu Wei 414ca9ae5ecSFu Wei return ret; 415ca9ae5ecSFu Wei } 416ca9ae5ecSFu Wei 417ca9ae5ecSFu Wei device_initcall(gtdt_sbsa_gwdt_init); 418