From: Fu Wei fu.wei@linaro.org
This patch adds support for parsing arch timer 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 fu.wei@linaro.org Signed-off-by: Hanjun Guo hanjun.guo@linaro.org --- drivers/acpi/acpi_gtdt.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 6 +++++ 2 files changed, 76 insertions(+)
diff --git a/drivers/acpi/acpi_gtdt.c b/drivers/acpi/acpi_gtdt.c index 54d7644e..edb5a8c 100644 --- a/drivers/acpi/acpi_gtdt.c +++ b/drivers/acpi/acpi_gtdt.c @@ -16,6 +16,8 @@ #include <linux/kernel.h> #include <linux/module.h>
+#include <clocksource/arm_arch_timer.h> + #undef pr_fmt #define pr_fmt(fmt) "GTDT: " fmt
@@ -83,3 +85,71 @@ static int __init acpi_gtdt_desc_init(struct acpi_table_header *table)
return gtdt->platform_timer_count; } + +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); +} + +/* + * Map the PPIs of per-cpu arch_timer. + * @type: the type of PPI + * Returns 0 if error. + */ +int __init acpi_gtdt_map_ppi(int type) +{ + struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; + + switch (type) { + case PHYS_SECURE_PPI: + return map_generic_timer_interrupt(gtdt->secure_el1_interrupt, + gtdt->secure_el1_flags); + case PHYS_NONSECURE_PPI: + return map_generic_timer_interrupt(gtdt->non_secure_el1_interrupt, + gtdt->non_secure_el1_flags); + case VIRT_PPI: + return map_generic_timer_interrupt(gtdt->virtual_timer_interrupt, + gtdt->virtual_timer_flags); + + case HYP_PPI: + return map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt, + gtdt->non_secure_el2_flags); + default: + pr_err("ppi type error.\n"); + } + + return 0; +} + +/* + * acpi_gtdt_c3stop - got c3stop info from GTDT + * + * Returns 1 if the timer is powered in deep idle state, 0 otherwise. + */ +int __init acpi_gtdt_c3stop(void) +{ + struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; + + return !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON); +} + +int __init gtdt_arch_timer_init(struct acpi_table_header *table) +{ + if (table) + return acpi_gtdt_desc_init(table); + + pr_err("table pointer error.\n"); + + return -EINVAL; +} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 288fac5..8439579 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -532,6 +532,12 @@ 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 +int __init gtdt_arch_timer_init(struct acpi_table_header *table); +int __init acpi_gtdt_map_ppi(int type); +int __init acpi_gtdt_c3stop(void); +#endif + #else /* !CONFIG_ACPI */
#define acpi_disabled 1