On Friday, July 15, 2016 03:32:35 PM Fu Wei wrote:
Hi Rafael,
On 14 July 2016 at 04:30, Rafael J. Wysocki rafael@kernel.org wrote:
On Wed, Jul 13, 2016 at 7:53 PM, fu.wei@linaro.org wrote:
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/Kconfig | 5 ++ drivers/acpi/Makefile | 1 + drivers/acpi/arm64/Kconfig | 15 ++++ drivers/acpi/arm64/Makefile | 1 + drivers/acpi/arm64/acpi_gtdt.c | 170 +++++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 6 ++ 6 files changed, 198 insertions(+)
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index b7e2e77..1cdc7d2 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -521,4 +521,9 @@ config XPOWER_PMIC_OPREGION
endif
+if ARM64 +source "drivers/acpi/arm64/Kconfig"
+endif
endif # ACPI diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 251ce85..1a94ff7 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -99,5 +99,6 @@ 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-$(CONFIG_ARM64) += arm64/
video-objs += acpi_video.o video_detect.o diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig new file mode 100644 index 0000000..ff5c253 --- /dev/null +++ b/drivers/acpi/arm64/Kconfig @@ -0,0 +1,15 @@ +# +# ACPI Configuration for ARM64 +#
+menu "The ARM64-specific ACPI Support"
+config ACPI_GTDT
bool "ACPI GTDT table Support"This should depend on ARM64.
Also I wonder if it needs to be user-selectable? Wouldn't it be better to enable it by default when building for ARM64 with ACPI?
helpGTDT (Generic Timer Description Table) provides informationfor per-processor timers and Platform (memory-mapped) timersfor ARM platforms. Select this option to provide informationneeded for the timers init.+endmenu diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile new file mode 100644 index 0000000..466de6b --- /dev/null +++ b/drivers/acpi/arm64/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_ACPI_GTDT) += acpi_gtdt.o diff --git a/drivers/acpi/arm64/acpi_gtdt.c b/drivers/acpi/arm64/acpi_gtdt.c new file mode 100644 index 0000000..9ee977d --- /dev/null +++ b/drivers/acpi/arm64/acpi_gtdt.c @@ -0,0 +1,170 @@ +/*
- ARM Specific GTDT table Support
- Copyright (C) 2016, Linaro Ltd.
- Author: Daniel Lezcano daniel.lezcano@linaro.org
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/init.h> +#include <linux/kernel.h> +#include <linux/module.h>
+#include <clocksource/arm_arch_timer.h>
+#undef pr_fmt +#define pr_fmt(fmt) "GTDT: " fmt
I would add "ACPI" to the prefix too if I were you, but that's me.
good idea, you are right, will do
+typedef struct {
struct acpi_table_gtdt *gtdt;void *platform_timer_start;void *gtdt_end;+} acpi_gtdt_desc_t;
+static acpi_gtdt_desc_t acpi_gtdt_desc __initdata;
+static inline void *next_platform_timer(void *platform_timer) +{
struct acpi_gtdt_header *gh = platform_timer;platform_timer += gh->length;if (platform_timer < acpi_gtdt_desc.gtdt_end)return platform_timer;return NULL;+}
+#define for_each_platform_timer(_g) \
for (_g = acpi_gtdt_desc.platform_timer_start; _g; \_g = next_platform_timer(_g))+static inline bool is_timer_block(void *platform_timer) +{
struct acpi_gtdt_header *gh = platform_timer;if (gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK)return true;return false;This is just too much code. It would suffice to do
return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK;+}
+static inline bool is_watchdog(void *platform_timer) +{
struct acpi_gtdt_header *gh = platform_timer;if (gh->type == ACPI_GTDT_TYPE_WATCHDOG)return true;return false;Just like above.
Thanks, this is better :-) will do
+}
+/*
- 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.
- */
+static int __init acpi_gtdt_desc_init(struct acpi_table_header *table) +{
struct acpi_table_gtdt *gtdt = container_of(table,struct acpi_table_gtdt,header);acpi_gtdt_desc.gtdt = gtdt;acpi_gtdt_desc.gtdt_end = (void *)table + table->length;if (table->revision < 2) {pr_info("Revision:%d doesn't support Platform Timers.\n",table->revision);Is it really useful to print this message (and the one below) at the "info" level? What about changing them to pr_debug()?
yes, pr_debug is better, thanks :-) will do
return 0;}if (!gtdt->platform_timer_count) {pr_info("No Platform Timer.\n");return 0;}acpi_gtdt_desc.platform_timer_start = (void *)gtdt +gtdt->platform_timer_offset;if (acpi_gtdt_desc.platform_timer_start <(void *)table + sizeof(struct acpi_table_gtdt)) {pr_err(FW_BUG "Platform Timer pointer error.\n");Why pr_err()?
if (true), that means the GTDT table has bugs.
And that's not a very useful piece of information unless you're debugging the platform, is it?
Thanks, Rafael