From 5f1ae4ebe578319a0cd5dae9591dd426070be106 Mon Sep 17 00:00:00 2001 From: Fu Wei Date: Sat, 1 Apr 2017 01:51:01 +0800 Subject: acpi/arm64: Add GTDT table parse driver This patch adds support for parsing arch timer info in GTDT, provides some kernel APIs to parse all the PPIs and always-on info in GTDT and export them. By this driver, we can simplify arm_arch_timer drivers, and separate the ACPI GTDT knowledge from it. Signed-off-by: Fu Wei Signed-off-by: Hanjun Guo Acked-by: Rafael J. Wysocki Tested-by: Xiongfeng Wang Reviewed-by: Hanjun Guo Tested-by: Hanjun Guo Acked-by: Lorenzo Pieralisi Signed-off-by: Mark Rutland --- drivers/acpi/arm64/Kconfig | 3 + drivers/acpi/arm64/Makefile | 1 + drivers/acpi/arm64/gtdt.c | 157 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 161 insertions(+) create mode 100644 drivers/acpi/arm64/gtdt.c (limited to 'drivers/acpi') diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig index 4616da4c15be..5a6f80fce0d6 100644 --- a/drivers/acpi/arm64/Kconfig +++ b/drivers/acpi/arm64/Kconfig @@ -4,3 +4,6 @@ config ACPI_IORT bool + +config ACPI_GTDT + bool diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile index 72331f2ce0e9..1017def2ea12 100644 --- a/drivers/acpi/arm64/Makefile +++ b/drivers/acpi/arm64/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_ACPI_IORT) += iort.o +obj-$(CONFIG_ACPI_GTDT) += gtdt.o diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c new file mode 100644 index 000000000000..3d95af8f73c6 --- /dev/null +++ b/drivers/acpi/arm64/gtdt.c @@ -0,0 +1,157 @@ +/* + * ARM Specific GTDT table Support + * + * Copyright (C) 2016, Linaro Ltd. + * Author: Daniel Lezcano + * Fu Wei + * Hanjun Guo + * + * 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 +#include +#include + +#include + +#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 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; +} -- cgit v1.2.3