acpi_table_parse() will find table with table id and run handler on it. So we use CLOCKSOURCE_ACPI_DECLARE to decalare timer tables and glue its handler, then initialize them in clocksource_acpi_init().
Signed-off-by: Hanjun Guo hanjun.guo@linaro.org Signed-off-by: Amit Daniel Kachhap amit.daniel@samsung.com --- drivers/clocksource/Makefile | 1 + drivers/clocksource/arm_arch_timer.c | 1 + drivers/clocksource/clksrc-acpi.c | 36 ++++++++++++++++++++++++++++++++++ include/linux/clocksource.h | 3 +++ 4 files changed, 41 insertions(+) create mode 100644 drivers/clocksource/clksrc-acpi.c
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 33621ef..2304c99 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -1,4 +1,5 @@ obj-$(CONFIG_CLKSRC_OF) += clksrc-of.o +obj-$(CONFIG_ACPI) += clksrc-acpi.o obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o obj-$(CONFIG_X86_CYCLONE_TIMER) += cyclone.o obj-$(CONFIG_X86_PM_TIMER) += acpi_pm.o diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 1fa5f67..6489037 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -738,6 +738,7 @@ void __init arch_timer_acpi_init(struct acpi_table_header *table) arch_timers_present |= ARCH_CP15_TIMER; arch_timer_init(); } +CLOCKSOURCE_ACPI_DECLARE(armv8_arch_timer, "GTDT", arch_timer_acpi_init); #endif
static void __init arch_timer_mem_init(struct device_node *np) diff --git a/drivers/clocksource/clksrc-acpi.c b/drivers/clocksource/clksrc-acpi.c new file mode 100644 index 0000000..41efc83 --- /dev/null +++ b/drivers/clocksource/clksrc-acpi.c @@ -0,0 +1,36 @@ +/* + * Copyright (c) 2014, Hanjun Guo hanjun.guo@linaro.org + * Copyright (c) 2014, Amit Daniel Kachhap amit.daniel@samsung.com + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see http://www.gnu.org/licenses/. + */ + +#include <linux/init.h> +#include <linux/acpi.h> +#include <linux/clocksource.h> + +extern struct acpi_device_id __clksrc_acpi_table[]; + +static const struct acpi_device_id __clksrc_acpi_table_sentinel + __used __section(__clksrc_acpi_table_end); + +void __init clocksource_acpi_init(void) +{ + const struct acpi_device_id *id; + acpi_tbl_table_handler init_func; + + for (id = __clksrc_acpi_table; id->id[0]; id++) { + init_func = (acpi_tbl_table_handler)id->driver_data; + acpi_table_parse(id->id, init_func); + } +} diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 1d500cf..9bee8b3 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -361,12 +361,15 @@ static inline void clocksource_of_init(void) {} #endif
#ifdef CONFIG_ACPI +extern void clocksource_acpi_init(void); + #define CLOCKSOURCE_ACPI_DECLARE(name, compat, fn) \ static const struct acpi_device_id __clksrc_acpi_table_##name \ __used __section(__clksrc_acpi_table) \ = { .id = compat, \ .driver_data = (kernel_ulong_t)fn } #else +static inline void clocksource_acpi_init(void) { return; } #define CLOCKSOURCE_ACPI_DECLARE(name, compat, fn) #endif