[PATCH RFC 1/3] ACPI: add GTDT table parse driver into ACPI driver
fu.wei at linaro.org
fu.wei at linaro.org
Wed Oct 28 07:32:03 PDT 2015
From: Fu Wei <fu.wei at linaro.org>
This driver adds support for parsing all kinds of timer in GTDT:
(1)arch timer: provide a kernel API to parse all the PPIs and
always-on info in GTDT and export them by arch_timer_data struct.
(2)memory-mapped timer: provide several kernel APIs to parse
GT Block Structure in GTDT, export those info by return value
and arch_timer_mem_data struct.
(3)SBSA Generic Watchdog: parse all info in SBSA Generic Watchdog
Structure in GTDT, and creating a platform device with that
information. This allows the operating system to obtain device
data from the resource of platform device.
The platform device named "sbsa-gwdt" can be used by the ARM SBSA
Generic Watchdog driver.
By this driver, we can simplify all the relevant drivers, and
separate all the ACPI GTDT knowledge from them.
Signed-off-by: Fu Wei <fu.wei at linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo at linaro.org>
---
drivers/acpi/Kconfig | 9 +
drivers/acpi/Makefile | 1 +
drivers/acpi/gtdt.c | 367 +++++++++++++++++++++++++++++++++++
drivers/clocksource/arm_arch_timer.c | 2 -
include/clocksource/arm_arch_timer.h | 19 ++
include/linux/acpi.h | 17 ++
6 files changed, 413 insertions(+), 2 deletions(-)
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index ce97a59..cf5fab5 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -501,4 +501,13 @@ config XPOWER_PMIC_OPREGION
endif
+config ACPI_GTDT
+ bool "ACPI GTDT Support"
+ depends on ARM64
+ help
+ GTDT (Generic Timer Description Table) provides information
+ for per-processor timers and Platform (memory-mapped) timers
+ for ARM platforms. Select this option to provide information
+ needed for the timers init.
+
endif # ACPI
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 675eaf3..ac42e31 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -96,5 +96,6 @@ obj-$(CONFIG_ACPI_EXTLOG) += acpi_extlog.o
obj-$(CONFIG_PMIC_OPREGION) += pmic/intel_pmic.o
obj-$(CONFIG_CRC_PMIC_OPREGION) += pmic/intel_pmic_crc.o
obj-$(CONFIG_XPOWER_PMIC_OPREGION) += pmic/intel_pmic_xpower.o
+obj-$(CONFIG_ACPI_GTDT) += gtdt.o
video-objs += acpi_video.o video_detect.o
diff --git a/drivers/acpi/gtdt.c b/drivers/acpi/gtdt.c
new file mode 100644
index 0000000..d15ea91
--- /dev/null
+++ b/drivers/acpi/gtdt.c
@@ -0,0 +1,367 @@
+/*
+ * ARM Specific GTDT table Support
+ *
+ * Copyright (C) 2015, Linaro Ltd.
+ * Author: Fu Wei <fu.wei at linaro.org>
+ * Hanjun Guo <hanjun.guo at 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>
+
+static u32 platform_timer_count __initdata;
+static int gtdt_timers_existence __initdata;
+
+/*
+ * 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_info_init(struct acpi_table_header *table)
+{
+ void *gtdt_end, *platform_timer_struct, *platform_timer;
+ struct acpi_gtdt_header *header;
+ struct acpi_table_gtdt *gtdt;
+ u32 i;
+
+ gtdt = container_of(table, struct acpi_table_gtdt, header);
+ if (!gtdt) {
+ pr_err("GTDT: table pointer error, bad table.\n");
+ return NULL;
+ }
+ gtdt_end = (void *)table + table->length;
+ gtdt_timers_existence |= ARCH_CP15_TIMER;
+
+ if (table->revision < 2) {
+ pr_info("GTDT: Revision:%d doesn't support Platform Timers.\n",
+ table->revision);
+ return NULL;
+ }
+
+ platform_timer_count = gtdt->platform_timer_count;
+ if (!platform_timer_count) {
+ pr_info("GTDT: No Platform Timer structures.\n");
+ return NULL;
+ }
+
+ platform_timer_struct = (void *)gtdt + gtdt->platform_timer_offset;
+ if (platform_timer_struct < (void *)table +
+ sizeof(struct acpi_table_gtdt)) {
+ pr_err("GTDT: Platform Timer pointer error, bad table.\n");
+ return NULL;
+ }
+
+ platform_timer = platform_timer_struct;
+ for (i = 0; i < platform_timer_count; i++) {
+ if (platform_timer > gtdt_end) {
+ pr_warn("GTDT: subtable pointer overflows, bad table\n");
+ platform_timer_count = i;
+ break;
+ }
+ header = (struct acpi_gtdt_header *)platform_timer;
+ if (header->type == ACPI_GTDT_TYPE_TIMER_BLOCK)
+ gtdt_timers_existence |= ARCH_MEM_TIMER;
+ else if (header->type == ACPI_GTDT_TYPE_WATCHDOG)
+ gtdt_timers_existence |= ARCH_WD_TIMER;
+ platform_timer += header->length;
+ }
+
+ return platform_timer_struct;
+}
+
+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_data_init(struct acpi_table_header *table,
+ struct arch_timer_data *data)
+{
+ struct acpi_table_gtdt *gtdt;
+
+ if (acpi_disabled)
+ return -EINVAL;
+
+ if (!gtdt_timers_existence)
+ platform_timer_info_init(table);
+
+ gtdt = container_of(table, struct acpi_table_gtdt, header);
+ if (!gtdt || !data)
+ return -EINVAL;
+
+ data->phys_secure_ppi =
+ map_generic_timer_interrupt(gtdt->secure_el1_interrupt,
+ gtdt->secure_el1_flags);
+
+ data->phys_nonsecure_ppi =
+ map_generic_timer_interrupt(gtdt->non_secure_el1_interrupt,
+ gtdt->non_secure_el1_flags);
+
+ data->virt_ppi =
+ map_generic_timer_interrupt(gtdt->virtual_timer_interrupt,
+ gtdt->virtual_timer_flags);
+
+ data->hyp_ppi =
+ map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
+ gtdt->non_secure_el2_flags);
+
+ data->c3stop = !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON);
+
+ return 0;
+}
+
+bool __init gtdt_timer_is_available(int type)
+{
+ return gtdt_timers_existence | type;
+}
+
+/*
+ * Helper function for getting the pointer of platform_timer_struct.
+ */
+static void __init *get_platform_timer_struct(struct acpi_table_header *table)
+{
+ struct acpi_table_gtdt *gtdt;
+
+ gtdt = container_of(table, struct acpi_table_gtdt, header);
+ if (gtdt)
+ return (void *)gtdt + gtdt->platform_timer_offset;
+
+ pr_err("GTDT: table pointer error, bad table.\n");
+ return NULL;
+}
+
+ /*
+ * Get the pointer of GT Block Structure in GTDT table
+ */
+void __init *gtdt_gt_block(struct acpi_table_header *table, int index)
+{
+ struct acpi_gtdt_header *header;
+ void *platform_timer;
+ int i, j;
+
+ if (!gtdt_timers_existence)
+ platform_timer = platform_timer_info_init(table);
+ else
+ platform_timer = get_platform_timer_struct(table);
+
+ if (!gtdt_timer_is_available(ARCH_MEM_TIMER))
+ return NULL;
+
+ for (i = 0, j = 0; i < platform_timer_count; i++) {
+ header = (struct acpi_gtdt_header *)platform_timer;
+ if (header->type == ACPI_GTDT_TYPE_TIMER_BLOCK && j++ == index)
+ return platform_timer;
+ platform_timer += header->length;
+ }
+
+ return NULL;
+}
+
+/*
+ * Get the timer_count(the number of timer frame) of a GT Block in GTDT table
+ */
+u32 __init gtdt_gt_timer_count(struct acpi_gtdt_timer_block *gt_block)
+{
+ if (!gt_block) {
+ pr_err("GTDT: invalid GT Block baseaddr.\n");
+ return 0;
+ }
+
+ return gt_block->timer_count;
+}
+
+/*
+ * Get the physical address of GT Block in GTDT table
+ */
+void __init *gtdt_gt_cntctlbase(struct acpi_gtdt_timer_block *gt_block)
+{
+ if (!gt_block) {
+ pr_err("GTDT: invalid GT Block baseaddr.\n");
+ return NULL;
+ }
+
+ return (void *)gt_block->block_address;
+}
+
+/*
+ * 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;
+
+ if (!(gt_block && gt_block->timer_count))
+ return NULL;
+
+ 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;
+
+ pr_err("GTDT: invalid GT Block timer frame entry addr.\n");
+ return NULL;
+}
+
+/*
+ * Get the GT timer Frame Number(ID) in a GT Block Timer Structure.
+ * The maximum Frame Number(ID) is (ARCH_TIMER_MEM_MAX_FRAME - 1),
+ * so returning ARCH_TIMER_MEM_MAX_FRAME means error.
+ */
+u32 __init gtdt_gt_frame_number(struct acpi_gtdt_timer_block *gt_block,
+ int index)
+{
+ struct acpi_gtdt_timer_entry *frame;
+
+ frame = (struct acpi_gtdt_timer_entry *)gtdt_gt_timer_frame(gt_block,
+ index);
+ if (frame)
+ return frame->frame_number;
+
+ return ARCH_TIMER_MEM_MAX_FRAME;
+}
+
+/*
+ * Get the GT timer Frame data in a GT Block Timer Structure
+ */
+int __init gtdt_gt_timer_data(struct acpi_gtdt_timer_block *gt_block,
+ int index, bool virt,
+ struct arch_timer_mem_data *data)
+{
+ struct acpi_gtdt_timer_entry *frame;
+
+ frame = (struct acpi_gtdt_timer_entry *)gtdt_gt_timer_frame(gt_block,
+ index);
+ if (!frame)
+ return -EINVAL;
+
+ data->cntbase_phy = (phys_addr_t)frame->base_address;
+ if (virt)
+ data->irq = map_generic_timer_interrupt(
+ frame->virtual_timer_interrupt,
+ frame->virtual_timer_flags);
+ else
+ data->irq = map_generic_timer_interrupt(frame->timer_interrupt,
+ frame->timer_flags);
+
+ 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_generic_timer_interrupt(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_IRQ(irq),
+ DEFINE_RES_MEM(wd->control_frame_address, SZ_4K),
+ DEFINE_RES_MEM(wd->refresh_frame_address, SZ_4K),
+ };
+
+ pr_debug("GTDT: 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 &&
+ wd->timer_interrupt)) {
+ pr_err("GTDT: failed geting the device info.\n");
+ return -EINVAL;
+ }
+
+ if (irq < 0) {
+ pr_err("GTDT: failed to register GSI of the Watchdog GT.\n");
+ return -EINVAL;
+ }
+
+ /*
+ * 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));
+ if (IS_ERR(pdev)) {
+ acpi_unregister_gsi(wd->timer_interrupt);
+ return PTR_ERR(pdev);
+ }
+
+ return 0;
+}
+
+static int __init gtdt_sbsa_gwdt_parse(struct acpi_table_header *table)
+{
+ struct acpi_gtdt_header *header;
+ void *platform_timer;
+ int i, gwdt_index;
+ int ret = 0;
+
+ /*
+ * At this proint, we have got and validate some info about platform
+ * timer in platform_timer_info_init.
+ */
+ if (!gtdt_timer_is_available(ARCH_WD_TIMER))
+ return -EINVAL;
+
+ platform_timer = get_platform_timer_struct(table);
+
+ for (i = 0, gwdt_index = 0; i < platform_timer_count; i++) {
+ header = (struct acpi_gtdt_header *)platform_timer;
+ if (header->type == ACPI_GTDT_TYPE_WATCHDOG) {
+ ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_index);
+ if (ret)
+ pr_err("GTDT: failed to import subtable %d\n",
+ i);
+ else
+ gwdt_index++;
+ }
+ platform_timer += header->length;
+ }
+
+ return ret;
+}
+
+static int __init gtdt_sbsa_gwdt_init(void)
+{
+ if (acpi_disabled)
+ return 0;
+
+ return acpi_table_parse(ACPI_SIG_GTDT, gtdt_sbsa_gwdt_parse);
+}
+
+device_initcall(gtdt_sbsa_gwdt_init);
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index c64d543..e16fdad 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -40,8 +40,6 @@
#define CNTV_TVAL 0x38
#define CNTV_CTL 0x3c
-#define ARCH_CP15_TIMER BIT(0)
-#define ARCH_MEM_TIMER BIT(1)
static unsigned arch_timers_present __initdata;
static void __iomem *arch_counter_base;
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index 9916d0e..7a6d6dc 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -19,6 +19,10 @@
#include <linux/timecounter.h>
#include <linux/types.h>
+#define ARCH_CP15_TIMER BIT(0)
+#define ARCH_MEM_TIMER BIT(1)
+#define ARCH_WD_TIMER BIT(2)
+
#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
#define ARCH_TIMER_CTRL_IT_MASK (1 << 1)
#define ARCH_TIMER_CTRL_IT_STAT (1 << 2)
@@ -33,6 +37,8 @@ enum arch_timer_reg {
#define ARCH_TIMER_MEM_PHYS_ACCESS 2
#define ARCH_TIMER_MEM_VIRT_ACCESS 3
+#define ARCH_TIMER_MEM_MAX_FRAME 8
+
#define ARCH_TIMER_USR_PCT_ACCESS_EN (1 << 0) /* physical counter */
#define ARCH_TIMER_USR_VCT_ACCESS_EN (1 << 1) /* virtual counter */
#define ARCH_TIMER_VIRT_EVT_EN (1 << 2)
@@ -43,6 +49,19 @@ enum arch_timer_reg {
#define ARCH_TIMER_EVT_STREAM_FREQ 10000 /* 100us */
+struct arch_timer_data {
+ int phys_secure_ppi;
+ int phys_nonsecure_ppi;
+ int virt_ppi;
+ int hyp_ppi;
+ bool c3stop;
+};
+
+struct arch_timer_mem_data {
+ phys_addr_t cntbase_phy;
+ int irq;
+};
+
#ifdef CONFIG_ARM_ARCH_TIMER
extern u32 arch_timer_get_rate(void);
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 996d68f..687567d 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -462,6 +462,23 @@ void acpi_walk_dep_device_list(acpi_handle handle);
struct platform_device *acpi_create_platform_device(struct acpi_device *);
#define ACPI_PTR(_ptr) (_ptr)
+#ifdef CONFIG_ACPI_GTDT
+bool __init gtdt_timer_is_available(int type);
+
+struct arch_timer_data;
+int __init gtdt_arch_timer_data_init(struct acpi_table_header *table,
+ struct arch_timer_data *data);
+struct arch_timer_mem_data;
+void __init *gtdt_gt_block(struct acpi_table_header *table, int index);
+u32 __init gtdt_gt_timer_count(struct acpi_gtdt_timer_block *gt_block);
+void __init *gtdt_gt_cntctlbase(struct acpi_gtdt_timer_block *gt_block);
+u32 __init gtdt_gt_frame_number(struct acpi_gtdt_timer_block *gt_block,
+ int index);
+int __init gtdt_gt_timer_data(struct acpi_gtdt_timer_block *gt_block,
+ int index, bool virt,
+ struct arch_timer_mem_data *data);
+#endif
+
#else /* !CONFIG_ACPI */
#define acpi_disabled 1
--
2.4.3
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