On Wed, Jul 13, 2016 at 10:30:37PM +0200, Rafael J. Wysocki 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-$(CONFIG_ARM64) += arm64/
video-objs += acpi_video.o video_detect.o diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig new file mode 100644 index 0000000..ff5c253 --- /dev/null +++ b/drivers/acpi/arm64/Kconfig @@ -0,0 +1,15 @@ +# +# ACPI Configuration for ARM64 +#
+menu "The ARM64-specific ACPI Support"
+config ACPI_GTDT
bool "ACPI GTDT table Support"
This should depend on ARM64.
Also I wonder if it needs to be user-selectable? Wouldn't it be better to enable it by default when building for ARM64 with ACPI?
It is currently selected in patch 9, in the watchdog driver's Kconfig entry. Not sure if I like that; maybe the watchdog driver should depend on it instead ?
Guenter
help
GTDT (Generic Timer Description Table) provides information
for per-processor timers and Platform (memory-mapped) timers
for ARM platforms. Select this option to provide information
needed for the timers init.
+endmenu diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile new file mode 100644 index 0000000..466de6b --- /dev/null +++ b/drivers/acpi/arm64/Makefile @@ -0,0 +1 @@ +obj-$(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.
+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.
+}
+/*
- 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()?
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()?
acpi_gtdt_desc.platform_timer_start = NULL;
return -EINVAL;
}
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)
Why not bool?
+{
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");
This message is totally unuseful.
return -EINVAL;
+}
What is supposed to be calling this function?
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);
The __init thing is not necessary here.
+#endif
#else /* !CONFIG_ACPI */
#define acpi_disabled 1
Thanks, Rafael