On 29 March 2017 at 22:29, Fu Wei fu.wei@linaro.org wrote:
Hi Lorenzo,
On 28 March 2017 at 19:35, Lorenzo Pieralisi lorenzo.pieralisi@arm.com wrote:
On Wed, Mar 22, 2017 at 12:31:18AM +0800, fu.wei@linaro.org wrote:
From: Fu Wei fu.wei@linaro.org
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 fu.wei@linaro.org Signed-off-by: Hanjun Guo hanjun.guo@linaro.org Acked-by: Rafael J. Wysocki rafael.j.wysocki@intel.com
Acked-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com
Some nits below.
Tested-by: Xiongfeng Wang wangxiongfeng2@huawei.com Reviewed-by: Hanjun Guo hanjun.guo@linaro.org Tested-by: Hanjun Guo hanjun.guo@linaro.org
arch/arm64/Kconfig | 1 + drivers/acpi/arm64/Kconfig | 3 + drivers/acpi/arm64/Makefile | 1 + drivers/acpi/arm64/gtdt.c | 157 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 6 ++ 5 files changed, 168 insertions(+)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 3741859..7e2baec 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2,6 +2,7 @@ config ARM64 def_bool y select ACPI_CCA_REQUIRED if ACPI select ACPI_GENERIC_GSI if ACPI
select ACPI_GTDT if ACPI select ACPI_REDUCED_HARDWARE_ONLY if ACPI select ACPI_MCFG if ACPI select ACPI_SPCR_TABLE if ACPI
diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig index 4616da4..5a6f80f 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 72331f2..1017def 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 0000000..8a03b4b --- /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 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 <clocksource/arm_arch_timer.h>
+#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: Linux on arm64 isn't supported on the secure side.
Note: Secure state is not managed by the kernel on ARM64 systems.
Is that what you wanted to say ?
- 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: 1 if the timer can be in deep idle state, 0 otherwise.
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 0;
+}
+/**
- acpi_gtdt_init() - Get the info of GTDT table to prepare for further init.
- @table: The pointer to GTDT table.
- @platform_timer_count: The pointer of int variate for returning the
I do not understand what this means.
number of platform timers. It can be NULL, if
driver don't need this info.
driver doesn't
- Return: 0 if success, -EINVAL if error.
- */
+int __init acpi_gtdt_init(struct acpi_table_header *table,
int *platform_timer_count)
+{
int ret = 0;
int timer_count = 0;
void *platform_timer = NULL;
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;
if (table->revision < 2)
pr_warn("Revision:%d doesn't support Platform Timers.\n",
table->revision);
Ok, two points here. First, I am not sure why you should warn if the table revision is < 2, is that a FW bug ? I do not think it is, you can just return 0.
else if (!gtdt->platform_timer_count)
pr_debug("No Platform Timer.\n");
Ditto. Why keep executing ? There is nothing to do, just bail out with a return 0.
else
timer_count = gtdt->platform_timer_count;
if (timer_count) {
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");
timer_count = 0;
platform_timer = NULL;
ret = -EINVAL;
Same here, I suspect you want to consolidate the return path (I missed previous rounds of reviews so you should not worry too much, I can clean this up later) but to me a:
return -EINVAL;
would just do.
For this problem, Can I do this:
/**
- 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; } if (platform_timer_count) *platform_timer_count = gtdt->platform_timer_count;
sorry , this should be moved,
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;
Here is the right place
return 0;
}
Lorenzo
}
}
acpi_gtdt_desc.platform_timer = platform_timer;
if (platform_timer_count)
*platform_timer_count = timer_count;
return ret;
+} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 9b05886..4b5c146 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -595,6 +595,12 @@ enum acpi_reconfig_event { int acpi_reconfig_notifier_register(struct notifier_block *nb); int acpi_reconfig_notifier_unregister(struct notifier_block *nb);
+#ifdef CONFIG_ACPI_GTDT +int acpi_gtdt_init(struct acpi_table_header *table, int *platform_timer_count); +int acpi_gtdt_map_ppi(int type); +bool acpi_gtdt_c3stop(int type); +#endif
#else /* !CONFIG_ACPI */
#define acpi_disabled 1
2.9.3
-- Best regards,
Fu Wei Software Engineer Red Hat