| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * ARM Specific GTDT table Support |
| * |
| * Copyright (C) 2016, Linaro Ltd. |
| * Author: Daniel Lezcano <daniel.lezcano@linaro.org> |
| * Fu Wei <fu.wei@linaro.org> |
| * Hanjun Guo <hanjun.guo@linaro.org> |
| */ |
| |
| #include <linux/acpi.h> |
| #include <linux/init.h> |
| #include <linux/irqdomain.h> |
| #include <linux/kernel.h> |
| #include <linux/platform_device.h> |
| |
| #include <clocksource/arm_arch_timer.h> |
| |
| #undef pr_fmt |
| #define pr_fmt(fmt) "ACPI GTDT: " fmt |
| |
| /** |
| * struct acpi_gtdt_descriptor - Store the key info of GTDT for all functions |
| * @gtdt: The pointer to the struct acpi_table_gtdt of GTDT table. |
| * @gtdt_end: The pointer to the end of GTDT table. |
| * @platform_timer: The pointer to the start of Platform Timer Structure |
| * |
| * The struct store the key info of GTDT table, it should be initialized by |
| * acpi_gtdt_init. |
| */ |
| struct acpi_gtdt_descriptor { |
| struct acpi_table_gtdt *gtdt; |
| void *gtdt_end; |
| void *platform_timer; |
| }; |
| |
| static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; |
| |
| static __init bool platform_timer_valid(void *platform_timer) |
| { |
| struct acpi_gtdt_header *gh = platform_timer; |
| |
| return (platform_timer >= (void *)(acpi_gtdt_desc.gtdt + 1) && |
| platform_timer < acpi_gtdt_desc.gtdt_end && |
| gh->length != 0 && |
| platform_timer + gh->length <= acpi_gtdt_desc.gtdt_end); |
| } |
| |
| static __init void *next_platform_timer(void *platform_timer) |
| { |
| struct acpi_gtdt_header *gh = platform_timer; |
| |
| return platform_timer + gh->length; |
| } |
| |
| #define for_each_platform_timer(_g) \ |
| for (_g = acpi_gtdt_desc.platform_timer; platform_timer_valid(_g);\ |
| _g = next_platform_timer(_g)) |
| |
| static inline bool is_timer_block(void *platform_timer) |
| { |
| struct acpi_gtdt_header *gh = platform_timer; |
| |
| return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK; |
| } |
| |
| static inline bool is_non_secure_watchdog(void *platform_timer) |
| { |
| struct acpi_gtdt_header *gh = platform_timer; |
| struct acpi_gtdt_watchdog *wd = platform_timer; |
| |
| if (gh->type != ACPI_GTDT_TYPE_WATCHDOG) |
| return false; |
| |
| return !(wd->timer_flags & ACPI_GTDT_WATCHDOG_SECURE); |
| } |
| |
| static int __init map_gt_gsi(u32 interrupt, u32 flags) |
| { |
| int trigger, polarity; |
| |
| trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE |
| : ACPI_LEVEL_SENSITIVE; |
| |
| polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW |
| : ACPI_ACTIVE_HIGH; |
| |
| return acpi_register_gsi(NULL, interrupt, trigger, polarity); |
| } |
| |
| /** |
| * acpi_gtdt_map_ppi() - Map the PPIs of per-cpu arch_timer. |
| * @type: the type of PPI. |
| * |
| * Note: Secure state is not managed by the kernel on ARM64 systems. |
| * So we only handle the non-secure timer PPIs, |
| * ARCH_TIMER_PHYS_SECURE_PPI is treated as invalid type. |
| * |
| * Return: the mapped PPI value, 0 if error. |
| */ |
| int __init acpi_gtdt_map_ppi(int type) |
| { |
| struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; |
| |
| switch (type) { |
| case ARCH_TIMER_PHYS_NONSECURE_PPI: |
| return map_gt_gsi(gtdt->non_secure_el1_interrupt, |
| gtdt->non_secure_el1_flags); |
| case ARCH_TIMER_VIRT_PPI: |
| return map_gt_gsi(gtdt->virtual_timer_interrupt, |
| gtdt->virtual_timer_flags); |
| |
| case ARCH_TIMER_HYP_PPI: |
| return map_gt_gsi(gtdt->non_secure_el2_interrupt, |
| gtdt->non_secure_el2_flags); |
| default: |
| pr_err("Failed to map timer interrupt: invalid type.\n"); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * acpi_gtdt_c3stop() - Got c3stop info from GTDT according to the type of PPI. |
| * @type: the type of PPI. |
| * |
| * Return: true if the timer HW state is lost when a CPU enters an idle state, |
| * false otherwise |
| */ |
| bool __init acpi_gtdt_c3stop(int type) |
| { |
| struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; |
| |
| switch (type) { |
| case ARCH_TIMER_PHYS_NONSECURE_PPI: |
| return !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON); |
| |
| case ARCH_TIMER_VIRT_PPI: |
| return !(gtdt->virtual_timer_flags & ACPI_GTDT_ALWAYS_ON); |
| |
| case ARCH_TIMER_HYP_PPI: |
| return !(gtdt->non_secure_el2_flags & ACPI_GTDT_ALWAYS_ON); |
| |
| default: |
| pr_err("Failed to get c3stop info: invalid type.\n"); |
| } |
| |
| return false; |
| } |
| |
| /** |
| * acpi_gtdt_init() - Get the info of GTDT table to prepare for further init. |
| * @table: The pointer to GTDT table. |
| * @platform_timer_count: It points to a integer variable which is used |
| * for storing the number of platform timers. |
| * This pointer could be NULL, if the caller |
| * doesn't need this info. |
| * |
| * Return: 0 if success, -EINVAL if error. |
| */ |
| int __init acpi_gtdt_init(struct acpi_table_header *table, |
| int *platform_timer_count) |
| { |
| void *platform_timer; |
| struct acpi_table_gtdt *gtdt; |
| int cnt = 0; |
| |
| gtdt = container_of(table, struct acpi_table_gtdt, header); |
| acpi_gtdt_desc.gtdt = gtdt; |
| acpi_gtdt_desc.gtdt_end = (void *)table + table->length; |
| acpi_gtdt_desc.platform_timer = NULL; |
| if (platform_timer_count) |
| *platform_timer_count = 0; |
| |
| if (table->revision < 2) { |
| pr_warn("Revision:%d doesn't support Platform Timers.\n", |
| table->revision); |
| return 0; |
| } |
| |
| if (!gtdt->platform_timer_count) { |
| pr_debug("No Platform Timer.\n"); |
| return 0; |
| } |
| |
| acpi_gtdt_desc.platform_timer = (void *)gtdt + gtdt->platform_timer_offset; |
| for_each_platform_timer(platform_timer) |
| cnt++; |
| |
| if (cnt != gtdt->platform_timer_count) { |
| acpi_gtdt_desc.platform_timer = NULL; |
| pr_err(FW_BUG "invalid timer data.\n"); |
| return -EINVAL; |
| } |
| |
| if (platform_timer_count) |
| *platform_timer_count = gtdt->platform_timer_count; |
| |
| return 0; |
| } |
| |
| static int __init gtdt_parse_timer_block(struct acpi_gtdt_timer_block *block, |
| struct arch_timer_mem *timer_mem) |
| { |
| int i; |
| struct arch_timer_mem_frame *frame; |
| struct acpi_gtdt_timer_entry *gtdt_frame; |
| |
| if (!block->timer_count) { |
| pr_err(FW_BUG "GT block present, but frame count is zero.\n"); |
| return -ENODEV; |
| } |
| |
| if (block->timer_count > ARCH_TIMER_MEM_MAX_FRAMES) { |
| pr_err(FW_BUG "GT block lists %d frames, ACPI spec only allows 8\n", |
| block->timer_count); |
| return -EINVAL; |
| } |
| |
| timer_mem->cntctlbase = (phys_addr_t)block->block_address; |
| /* |
| * The CNTCTLBase frame is 4KB (register offsets 0x000 - 0xFFC). |
| * See ARM DDI 0487A.k_iss10775, page I1-5129, Table I1-3 |
| * "CNTCTLBase memory map". |
| */ |
| timer_mem->size = SZ_4K; |
| |
| gtdt_frame = (void *)block + block->timer_offset; |
| if (gtdt_frame + block->timer_count != (void *)block + block->header.length) |
| return -EINVAL; |
| |
| /* |
| * Get the GT timer Frame data for every GT Block Timer |
| */ |
| for (i = 0; i < block->timer_count; i++, gtdt_frame++) { |
| if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER) |
| continue; |
| if (gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES || |
| !gtdt_frame->base_address || !gtdt_frame->timer_interrupt) |
| goto error; |
| |
| frame = &timer_mem->frame[gtdt_frame->frame_number]; |
| |
| /* duplicate frame */ |
| if (frame->valid) |
| goto error; |
| |
| frame->phys_irq = map_gt_gsi(gtdt_frame->timer_interrupt, |
| gtdt_frame->timer_flags); |
| if (frame->phys_irq <= 0) { |
| pr_warn("failed to map physical timer irq in frame %d.\n", |
| gtdt_frame->frame_number); |
| goto error; |
| } |
| |
| if (gtdt_frame->virtual_timer_interrupt) { |
| frame->virt_irq = |
| map_gt_gsi(gtdt_frame->virtual_timer_interrupt, |
| gtdt_frame->virtual_timer_flags); |
| if (frame->virt_irq <= 0) { |
| pr_warn("failed to map virtual timer irq in frame %d.\n", |
| gtdt_frame->frame_number); |
| goto error; |
| } |
| } else { |
| pr_debug("virtual timer in frame %d not implemented.\n", |
| gtdt_frame->frame_number); |
| } |
| |
| frame->cntbase = gtdt_frame->base_address; |
| /* |
| * The CNTBaseN frame is 4KB (register offsets 0x000 - 0xFFC). |
| * See ARM DDI 0487A.k_iss10775, page I1-5130, Table I1-4 |
| * "CNTBaseN memory map". |
| */ |
| frame->size = SZ_4K; |
| frame->valid = true; |
| } |
| |
| return 0; |
| |
| error: |
| do { |
| if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER || |
| gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES) |
| continue; |
| |
| frame = &timer_mem->frame[gtdt_frame->frame_number]; |
| |
| if (frame->phys_irq > 0) |
| acpi_unregister_gsi(gtdt_frame->timer_interrupt); |
| frame->phys_irq = 0; |
| |
| if (frame->virt_irq > 0) |
| acpi_unregister_gsi(gtdt_frame->virtual_timer_interrupt); |
| frame->virt_irq = 0; |
| } while (i-- > 0 && gtdt_frame--); |
| |
| return -EINVAL; |
| } |
| |
| /** |
| * acpi_arch_timer_mem_init() - Get the info of all GT blocks in GTDT table. |
| * @timer_mem: The pointer to the array of struct arch_timer_mem for returning |
| * the result of parsing. The element number of this array should |
| * be platform_timer_count(the total number of platform timers). |
| * @timer_count: It points to a integer variable which is used for storing the |
| * number of GT blocks we have parsed. |
| * |
| * Return: 0 if success, -EINVAL/-ENODEV if error. |
| */ |
| int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, |
| int *timer_count) |
| { |
| int ret; |
| void *platform_timer; |
| |
| *timer_count = 0; |
| for_each_platform_timer(platform_timer) { |
| if (is_timer_block(platform_timer)) { |
| ret = gtdt_parse_timer_block(platform_timer, timer_mem); |
| if (ret) |
| return ret; |
| timer_mem++; |
| (*timer_count)++; |
| } |
| } |
| |
| if (*timer_count) |
| pr_info("found %d memory-mapped timer block(s).\n", |
| *timer_count); |
| |
| return 0; |
| } |
| |
| /* |
| * Initialize a SBSA generic Watchdog platform device info from GTDT |
| */ |
| static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd, |
| int index) |
| { |
| struct platform_device *pdev; |
| int irq; |
| |
| /* |
| * According to SBSA specification the size of refresh and control |
| * frames of SBSA Generic Watchdog is SZ_4K(Offset 0x000 – 0xFFF). |
| */ |
| struct resource res[] = { |
| DEFINE_RES_MEM(wd->control_frame_address, SZ_4K), |
| DEFINE_RES_MEM(wd->refresh_frame_address, SZ_4K), |
| {}, |
| }; |
| int nr_res = ARRAY_SIZE(res); |
| |
| pr_debug("found a Watchdog (0x%llx/0x%llx gsi:%u flags:0x%x).\n", |
| wd->refresh_frame_address, wd->control_frame_address, |
| wd->timer_interrupt, wd->timer_flags); |
| |
| if (!(wd->refresh_frame_address && wd->control_frame_address)) { |
| pr_err(FW_BUG "failed to get the Watchdog base address.\n"); |
| return -EINVAL; |
| } |
| |
| irq = map_gt_gsi(wd->timer_interrupt, wd->timer_flags); |
| res[2] = DEFINE_RES_IRQ(irq); |
| if (irq <= 0) { |
| pr_warn("failed to map the Watchdog interrupt.\n"); |
| nr_res--; |
| } |
| |
| /* |
| * Add a platform device named "sbsa-gwdt" to match the platform driver. |
| * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog |
| * The platform driver can get device info below by matching this name. |
| */ |
| pdev = platform_device_register_simple("sbsa-gwdt", index, res, nr_res); |
| if (IS_ERR(pdev)) { |
| if (irq > 0) |
| acpi_unregister_gsi(wd->timer_interrupt); |
| return PTR_ERR(pdev); |
| } |
| |
| return 0; |
| } |
| |
| static int __init gtdt_sbsa_gwdt_init(void) |
| { |
| void *platform_timer; |
| struct acpi_table_header *table; |
| int ret, timer_count, gwdt_count = 0; |
| |
| if (acpi_disabled) |
| return 0; |
| |
| if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table))) |
| return -EINVAL; |
| |
| /* |
| * Note: Even though the global variable acpi_gtdt_desc has been |
| * initialized by acpi_gtdt_init() while initializing the arch timers, |
| * when we call this function to get SBSA watchdogs info from GTDT, the |
| * pointers stashed in it are stale (since they are early temporary |
| * mappings carried out before acpi_permanent_mmap is set) and we need |
| * to re-initialize them with permanent mapped pointer values to let the |
| * GTDT parsing possible. |
| */ |
| ret = acpi_gtdt_init(table, &timer_count); |
| if (ret || !timer_count) |
| goto out_put_gtdt; |
| |
| for_each_platform_timer(platform_timer) { |
| if (is_non_secure_watchdog(platform_timer)) { |
| ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); |
| if (ret) |
| break; |
| gwdt_count++; |
| } |
| } |
| |
| if (gwdt_count) |
| pr_info("found %d SBSA generic Watchdog(s).\n", gwdt_count); |
| |
| out_put_gtdt: |
| acpi_put_table(table); |
| return ret; |
| } |
| |
| device_initcall(gtdt_sbsa_gwdt_init); |