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path: root/drivers/acpi/acpi_gtdt.c
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Diffstat (limited to 'drivers/acpi/acpi_gtdt.c')
-rw-r--r--drivers/acpi/acpi_gtdt.c309
1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/acpi/acpi_gtdt.c b/drivers/acpi/acpi_gtdt.c
new file mode 100644
index 000000000000..e54fadf997a9
--- /dev/null
+++ b/drivers/acpi/acpi_gtdt.c
@@ -0,0 +1,309 @@
+/*
+ * ARM Specific GTDT table Support
+ *
+ * Copyright (C) 2015, Linaro Ltd.
+ * Author: 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/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <clocksource/arm_arch_timer.h>
+
+#undef pr_fmt
+#define pr_fmt(fmt) "GTDT: " fmt
+
+typedef int (*platform_timer_handler)(void *platform_timer, int index,
+ void *data);
+
+static void *platform_timer_struct __initdata;
+static u32 platform_timer_count __initdata;
+static void *gtdt_end __initdata;
+
+static int __init for_platform_timer(enum acpi_gtdt_type type,
+ platform_timer_handler handler, void *data)
+{
+ struct acpi_gtdt_header *header;
+ int i, index, ret;
+ void *platform_timer = platform_timer_struct;
+
+ for (i = 0, index = 0; i < platform_timer_count; i++) {
+ if (platform_timer > gtdt_end) {
+ pr_err(FW_BUG "subtable pointer overflows.\n");
+ platform_timer_count = i;
+ break;
+ }
+ header = (struct acpi_gtdt_header *)platform_timer;
+ if (header->type == type) {
+ ret = handler(platform_timer, index, data);
+ if (ret)
+ pr_err("failed to handler subtable %d.\n", i);
+ else
+ index++;
+ }
+ platform_timer += header->length;
+ }
+
+ return index;
+}
+
+/*
+ * Get some basic info from GTDT table, and init the global variables above
+ * for all timers initialization of Generic Timer.
+ * This function does some validation on GTDT table, and will be run only once.
+ */
+static void __init platform_timer_init(struct acpi_table_header *table,
+ struct acpi_table_gtdt *gtdt)
+{
+ gtdt_end = (void *)table + table->length;
+
+ if (table->revision < 2) {
+ pr_info("Revision:%d doesn't support Platform Timers.\n",
+ table->revision);
+ return;
+ }
+
+ platform_timer_count = gtdt->platform_timer_count;
+ if (!platform_timer_count) {
+ pr_info("No Platform Timer structures.\n");
+ return;
+ }
+
+ platform_timer_struct = (void *)gtdt + gtdt->platform_timer_offset;
+ if (platform_timer_struct < (void *)table +
+ sizeof(struct acpi_table_gtdt)) {
+ pr_err(FW_BUG "Platform Timer pointer error.\n");
+ platform_timer_struct = NULL;
+ platform_timer_count = 0;
+ }
+}
+
+static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)
+{
+ int trigger, polarity;
+
+ if (!interrupt)
+ return 0;
+
+ 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);
+}
+
+/*
+ * Get the necessary info of arch_timer from GTDT table.
+ */
+int __init gtdt_arch_timer_init(struct acpi_table_header *table, int *ppi,
+ bool *c3stop, u32 *timer_count)
+{
+ struct acpi_table_gtdt *gtdt;
+
+ if (acpi_disabled || !table || !ppi || !c3stop)
+ return -EINVAL;
+
+ gtdt = container_of(table, struct acpi_table_gtdt, header);
+ if (!gtdt) {
+ pr_err("table pointer error.\n");
+ return -EINVAL;
+ }
+
+ ppi[PHYS_SECURE_PPI] =
+ map_generic_timer_interrupt(gtdt->secure_el1_interrupt,
+ gtdt->secure_el1_flags);
+
+ ppi[PHYS_NONSECURE_PPI] =
+ map_generic_timer_interrupt(gtdt->non_secure_el1_interrupt,
+ gtdt->non_secure_el1_flags);
+
+ ppi[VIRT_PPI] =
+ map_generic_timer_interrupt(gtdt->virtual_timer_interrupt,
+ gtdt->virtual_timer_flags);
+
+ ppi[HYP_PPI] =
+ map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
+ gtdt->non_secure_el2_flags);
+
+ *c3stop = !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON);
+
+ platform_timer_init(table, gtdt);
+ if (timer_count)
+ *timer_count = platform_timer_count;
+
+ return 0;
+}
+
+/*
+ * Helper function for getting the pointer of a timer frame in GT block.
+ */
+static void __init *gtdt_gt_timer_frame(struct acpi_gtdt_timer_block *gt_block,
+ int index)
+{
+ void *timer_frame = (void *)gt_block + gt_block->timer_offset +
+ sizeof(struct acpi_gtdt_timer_entry) * index;
+
+ if (timer_frame <= (void *)gt_block + gt_block->header.length -
+ sizeof(struct acpi_gtdt_timer_entry))
+ return timer_frame;
+
+ return NULL;
+}
+
+static int __init gtdt_parse_gt_block(void *platform_timer, int index,
+ void *data)
+{
+ struct acpi_gtdt_timer_block *block;
+ struct acpi_gtdt_timer_entry *frame;
+ struct gt_block_data *block_data;
+ int i, j;
+
+ if (!platform_timer || !data)
+ return -EINVAL;
+
+ block = platform_timer;
+ block_data = data + sizeof(struct gt_block_data) * index;
+
+ if (!block->block_address || !block->timer_count) {
+ pr_err(FW_BUG "invalid GT Block data.\n");
+ return -EINVAL;
+ }
+ block_data->cntctlbase_phy = (phys_addr_t)block->block_address;
+ block_data->timer_count = block->timer_count;
+
+ /*
+ * Get the GT timer Frame data for every GT Block Timer
+ */
+ for (i = 0, j = 0; i < block->timer_count; i++) {
+ frame = gtdt_gt_timer_frame(block, i);
+ if (!frame || !frame->base_address || !frame->timer_interrupt) {
+ pr_err(FW_BUG "invalid GT Block Timer data, skip.\n");
+ continue;
+ }
+ block_data->timer[j].frame_nr = frame->frame_number;
+ block_data->timer[j].cntbase_phy = frame->base_address;
+ block_data->timer[j].irq = map_generic_timer_interrupt(
+ frame->timer_interrupt,
+ frame->timer_flags);
+ if (frame->virtual_timer_interrupt)
+ block_data->timer[j].virt_irq =
+ map_generic_timer_interrupt(
+ frame->virtual_timer_interrupt,
+ frame->virtual_timer_flags);
+ j++;
+ }
+
+ if (j)
+ return 0;
+
+ block_data->cntctlbase_phy = (phys_addr_t)NULL;
+ block_data->timer_count = 0;
+
+ return -EINVAL;
+}
+
+/*
+ * Get the GT block info for memory-mapped timer from GTDT table.
+ * Please make sure we have called gtdt_arch_timer_init, because it helps to
+ * init the global variables.
+ */
+int __init gtdt_arch_timer_mem_init(struct gt_block_data *data)
+{
+ int ret = for_platform_timer(ACPI_GTDT_TYPE_TIMER_BLOCK,
+ gtdt_parse_gt_block, (void *)data);
+
+ pr_info("found %d memory-mapped timer block.\n", ret);
+
+ return ret;
+}
+
+/*
+ * Initialize a SBSA generic Watchdog platform device info from GTDT
+ */
+static int __init gtdt_import_sbsa_gwdt(void *platform_timer,
+ int index, void *data)
+{
+ struct platform_device *pdev;
+ struct acpi_gtdt_watchdog *wd = platform_timer;
+ int irq = map_generic_timer_interrupt(wd->timer_interrupt,
+ wd->timer_flags);
+ int no_irq = 1;
+
+ /*
+ * 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),
+ };
+
+ pr_debug("a Watchdog GT(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 getting the Watchdog GT frame addr.\n");
+ return -EINVAL;
+ }
+
+ if (!wd->timer_interrupt)
+ pr_warn(FW_BUG "failed getting the Watchdog GT GSIV.\n");
+ else if (irq <= 0)
+ pr_warn("failed to map the Watchdog GT GSIV.\n");
+ else
+ no_irq = 0;
+
+ /*
+ * Add a platform device named "sbsa-gwdt" to match the platform driver.
+ * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog
+ * The platform driver (like drivers/watchdog/sbsa_gwdt.c)can get device
+ * info below by matching this name.
+ */
+ pdev = platform_device_register_simple("sbsa-gwdt", index, res,
+ ARRAY_SIZE(res) - no_irq);
+ if (IS_ERR(pdev)) {
+ acpi_unregister_gsi(wd->timer_interrupt);
+ return PTR_ERR(pdev);
+ }
+
+ return 0;
+}
+
+static int __init gtdt_sbsa_gwdt_init(void)
+{
+ struct acpi_table_header *table;
+ struct acpi_table_gtdt *gtdt;
+ int ret;
+
+ if (acpi_disabled)
+ return 0;
+
+ if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table)))
+ return -EINVAL;
+
+ /* global variables initialization */
+ gtdt_end = (void *)table + table->length;
+ gtdt = container_of(table, struct acpi_table_gtdt, header);
+ platform_timer_struct = (void *)gtdt + gtdt->platform_timer_offset;
+
+ ret = for_platform_timer(ACPI_GTDT_TYPE_WATCHDOG,
+ gtdt_import_sbsa_gwdt, NULL);
+ pr_info("found %d SBSA generic Watchdog.\n", ret);
+
+ return 0;
+}
+
+device_initcall(gtdt_sbsa_gwdt_init);