v4.19.13 snapshot.
diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c
new file mode 100644
index 0000000..92f9edf
--- /dev/null
+++ b/drivers/acpi/arm64/gtdt.c
@@ -0,0 +1,417 @@
+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#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 inline void *next_platform_timer(void *platform_timer)
+{
+ struct acpi_gtdt_header *gh = platform_timer;
+
+ platform_timer += gh->length;
+ if (platform_timer < acpi_gtdt_desc.gtdt_end)
+ return platform_timer;
+
+ return NULL;
+}
+
+#define for_each_platform_timer(_g) \
+ for (_g = acpi_gtdt_desc.platform_timer; _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;
+
+ 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;
+ }
+
+ platform_timer = (void *)gtdt + gtdt->platform_timer_offset;
+ if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) {
+ pr_err(FW_BUG "invalid timer data.\n");
+ return -EINVAL;
+ }
+ acpi_gtdt_desc.platform_timer = platform_timer;
+ 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 = map_gt_gsi(wd->timer_interrupt, wd->timer_flags);
+
+ /*
+ * 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),
+ DEFINE_RES_IRQ(irq),
+ };
+ 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");
+ acpi_unregister_gsi(wd->timer_interrupt);
+ return -EINVAL;
+ }
+
+ 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)) {
+ 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)
+ return ret;
+
+ 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);
+
+ return ret;
+}
+
+device_initcall(gtdt_sbsa_gwdt_init);