[GIT PULL 00/16] clocksource: arm_arch_timer: GTDT-based MMIO timer support

[GIT PULL 00/16] clocksource: arm_arch_timer: GTDT-based MMIO timer support

[Mark Rutland]

Hi Daniel,

The series enables support for the MMIO architected timers (useful for
system-level idle), which need to be probed via the GTDT when using ACPI. 

I realise this is a little late, but I would very much appreciate if you could
pull these arch timer GTDT patches for v4.12. The series has been largely fine
for a while now, and the major hold-ups were edge cases in error handling which
have now been addressed.

The bulk of the series is a refactoring to cleanly separate the core driver, DT
probe path, and ACPI probe path. The final patch of the series adds GTDT-based
probing of the SBSA watchdog, using the new GTDT probing infrastructure. I've
tested the patches on arm and arm64 platforms.

The ACPI parts have all been appropriately acked, and it's preferred that these
all go through the clocksource tree.

The series is based on Marc's arch-timer-errata tag, which is alread in
tip/timers/core.

Thanks,
Mark.

The following changes since commit d003d029cea8a28139b4f9b88a36b8fac864f45b:

  arm64: arch_timer: Add HISILICON_ERRATUM_161010101 ACPI matching data (2017-04-07 11:22:10 +0100)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git tags/arch-timer-gtdt

for you to fetch changes up to ca9ae5ec4ef0ed13833b03297ab319676965492c:

  acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver (2017-04-19 17:00:15 +0100)

----------------------------------------------------------------
arch timer GTDT patches

- arch_timer cleanups and refactoring
- new common GTDT parser
- GTDT-based MMIO arch_timer support
- GTDT-based SBSA watchdog support

----------------------------------------------------------------
Fu Wei (16):
      clocksource: arm_arch_timer: clean up printk usage
      clocksource: arm_arch_timer: rename type macros
      clocksource: arm_arch_timer: rename the PPI enum
      clocksource: arm_arch_timer: move enums and defines to header file
      clocksource: arm_arch_timer: add a new enum for spi type
      clocksource: arm_arch_timer: rework PPI selection
      clocksource: arm_arch_timer: split dt-only rate handling
      clocksource: arm_arch_timer: refactor arch_timer_needs_probing
      clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init call
      clocksource: arm_arch_timer: add structs to describe MMIO timer
      clocksource: arm_arch_timer: split MMIO timer probing.
      acpi/arm64: Add GTDT table parse driver
      clocksource: arm_arch_timer: simplify ACPI support code.
      acpi/arm64: Add memory-mapped timer support in GTDT driver
      clocksource: arm_arch_timer: add GTDT support for memory-mapped timer
      acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver

 arch/arm64/Kconfig                   |   1 +
 drivers/acpi/arm64/Kconfig           |   3 +
 drivers/acpi/arm64/Makefile          |   1 +
 drivers/acpi/arm64/gtdt.c            | 417 +++++++++++++++++++++++++
 drivers/clocksource/arm_arch_timer.c | 573 +++++++++++++++++++++++------------
 include/clocksource/arm_arch_timer.h |  34 +++
 include/linux/acpi.h                 |   7 +
 7 files changed, 834 insertions(+), 202 deletions(-)
 create mode 100644 drivers/acpi/arm64/gtdt.c

[PATCH 01/16] clocksource: arm_arch_timer: clean up printk usage

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

Almost all string in the arm_arch_timer driver duplicate an common
prefix (though a few do not). For consistency, it would be better to use
pr_fmt(), and always use this prefix. At the same time, we may as well
clean up some whitespace issues in arch_timer_banner and
arch_timer_init.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 49 ++++++++++++++++++------------------
 1 file changed, 25 insertions(+), 24 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index bf9e9d7..467ee61 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -33,6 +33,9 @@
 
 #include <clocksource/arm_arch_timer.h>
 
+#undef pr_fmt
+#define pr_fmt(fmt) "arch_timer: " fmt
+
 #define CNTTIDR		0x08
 #define CNTTIDR_VIRT(n)	(BIT(1) << ((n) * 4))
 
@@ -846,22 +849,22 @@ static int arch_timer_starting_cpu(unsigned int cpu)
 
 	/* Check the timer frequency. */
 	if (arch_timer_rate == 0)
-		pr_warn("Architected timer frequency not available\n");
+		pr_warn("frequency not available\n");
 }
 
 static void arch_timer_banner(unsigned type)
 {
-	pr_info("Architected %s%s%s timer(s) running at %lu.%02luMHz (%s%s%s).\n",
-		     type & ARCH_CP15_TIMER ? "cp15" : "",
-		     type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  " and " : "",
-		     type & ARCH_MEM_TIMER ? "mmio" : "",
-		     (unsigned long)arch_timer_rate / 1000000,
-		     (unsigned long)(arch_timer_rate / 10000) % 100,
-		     type & ARCH_CP15_TIMER ?
-		     (arch_timer_uses_ppi == VIRT_PPI) ? "virt" : "phys" :
+	pr_info("%s%s%s timer(s) running at %lu.%02luMHz (%s%s%s).\n",
+		type & ARCH_CP15_TIMER ? "cp15" : "",
+		type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  " and " : "",
+		type & ARCH_MEM_TIMER ? "mmio" : "",
+		(unsigned long)arch_timer_rate / 1000000,
+		(unsigned long)(arch_timer_rate / 10000) % 100,
+		type & ARCH_CP15_TIMER ?
+			(arch_timer_uses_ppi == VIRT_PPI) ? "virt" : "phys" :
 			"",
-		     type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  "/" : "",
-		     type & ARCH_MEM_TIMER ?
+		type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  "/" : "",
+		type & ARCH_MEM_TIMER ?
 			arch_timer_mem_use_virtual ? "virt" : "phys" :
 			"");
 }
@@ -922,8 +925,7 @@ static void __init arch_counter_register(unsigned type)
 
 static void arch_timer_stop(struct clock_event_device *clk)
 {
-	pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
-		 clk->irq, smp_processor_id());
+	pr_debug("disable IRQ%d cpu #%d\n", clk->irq, smp_processor_id());
 
 	disable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi]);
 	if (arch_timer_has_nonsecure_ppi())
@@ -1016,8 +1018,7 @@ static int __init arch_timer_register(void)
 	}
 
 	if (err) {
-		pr_err("arch_timer: can't register interrupt %d (%d)\n",
-		       ppi, err);
+		pr_err("can't register interrupt %d (%d)\n", ppi, err);
 		goto out_free;
 	}
 
@@ -1070,7 +1071,7 @@ static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
 
 	ret = request_irq(irq, func, IRQF_TIMER, "arch_mem_timer", &t->evt);
 	if (ret) {
-		pr_err("arch_timer: Failed to request mem timer irq\n");
+		pr_err("Failed to request mem timer irq\n");
 		kfree(t);
 	}
 
@@ -1148,7 +1149,7 @@ static int __init arch_timer_init(void)
 		}
 
 		if (!has_ppi) {
-			pr_warn("arch_timer: No interrupt available, giving up\n");
+			pr_warn("No interrupt available, giving up\n");
 			return -EINVAL;
 		}
 	}
@@ -1162,7 +1163,7 @@ static int __init arch_timer_init(void)
 		return ret;
 
 	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[VIRT_PPI];
-	
+
 	return 0;
 }
 
@@ -1171,7 +1172,7 @@ static int __init arch_timer_of_init(struct device_node *np)
 	int i;
 
 	if (arch_timers_present & ARCH_CP15_TIMER) {
-		pr_warn("arch_timer: multiple nodes in dt, skipping\n");
+		pr_warn("multiple nodes in dt, skipping\n");
 		return 0;
 	}
 
@@ -1213,7 +1214,7 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	arch_timers_present |= ARCH_MEM_TIMER;
 	cntctlbase = of_iomap(np, 0);
 	if (!cntctlbase) {
-		pr_err("arch_timer: Can't find CNTCTLBase\n");
+		pr_err("Can't find CNTCTLBase\n");
 		return -ENXIO;
 	}
 
@@ -1228,7 +1229,7 @@ static int __init arch_timer_mem_init(struct device_node *np)
 		u32 cntacr;
 
 		if (of_property_read_u32(frame, "frame-number", &n)) {
-			pr_err("arch_timer: Missing frame-number\n");
+			pr_err("Missing frame-number\n");
 			of_node_put(frame);
 			goto out;
 		}
@@ -1258,7 +1259,7 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	base = arch_counter_base = of_io_request_and_map(best_frame, 0,
 							 "arch_mem_timer");
 	if (IS_ERR(base)) {
-		pr_err("arch_timer: Can't map frame's registers\n");
+		pr_err("Can't map frame's registers\n");
 		goto out;
 	}
 
@@ -1269,7 +1270,7 @@ static int __init arch_timer_mem_init(struct device_node *np)
 
 	ret = -EINVAL;
 	if (!irq) {
-		pr_err("arch_timer: Frame missing %s irq",
+		pr_err("Frame missing %s irq.\n",
 		       arch_timer_mem_use_virtual ? "virt" : "phys");
 		goto out;
 	}
@@ -1311,7 +1312,7 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 	struct acpi_table_gtdt *gtdt;
 
 	if (arch_timers_present & ARCH_CP15_TIMER) {
-		pr_warn("arch_timer: already initialized, skipping\n");
+		pr_warn("already initialized, skipping\n");
 		return -EINVAL;
 	}
 
-- 
1.9.1

[PATCH 02/16] clocksource: arm_arch_timer: rename type macros

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

In preparation for moving the type macros out into a header, rename
these so they are namespaced w.r.t. the arch timer. We'll apply the same
prefix to other definitions in subsequent patches. This will aid
consistency and avoid potential name clahses when this move occurs.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 43 +++++++++++++++++++-----------------
 1 file changed, 23 insertions(+), 20 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 467ee61..38bddb9 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -55,8 +55,8 @@
 #define CNTV_TVAL	0x38
 #define CNTV_CTL	0x3c
 
-#define ARCH_CP15_TIMER	BIT(0)
-#define ARCH_MEM_TIMER	BIT(1)
+#define ARCH_TIMER_TYPE_CP15		BIT(0)
+#define ARCH_TIMER_TYPE_MEM		BIT(1)
 static unsigned arch_timers_present __initdata;
 
 static void __iomem *arch_counter_base;
@@ -686,7 +686,7 @@ static void __arch_timer_setup(unsigned type,
 {
 	clk->features = CLOCK_EVT_FEAT_ONESHOT;
 
-	if (type == ARCH_CP15_TIMER) {
+	if (type == ARCH_TIMER_TYPE_CP15) {
 		if (arch_timer_c3stop)
 			clk->features |= CLOCK_EVT_FEAT_C3STOP;
 		clk->name = "arch_sys_timer";
@@ -811,7 +811,7 @@ static int arch_timer_starting_cpu(unsigned int cpu)
 	struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt);
 	u32 flags;
 
-	__arch_timer_setup(ARCH_CP15_TIMER, clk);
+	__arch_timer_setup(ARCH_TIMER_TYPE_CP15, clk);
 
 	flags = check_ppi_trigger(arch_timer_ppi[arch_timer_uses_ppi]);
 	enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], flags);
@@ -855,16 +855,17 @@ static int arch_timer_starting_cpu(unsigned int cpu)
 static void arch_timer_banner(unsigned type)
 {
 	pr_info("%s%s%s timer(s) running at %lu.%02luMHz (%s%s%s).\n",
-		type & ARCH_CP15_TIMER ? "cp15" : "",
-		type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  " and " : "",
-		type & ARCH_MEM_TIMER ? "mmio" : "",
+		type & ARCH_TIMER_TYPE_CP15 ? "cp15" : "",
+		type == (ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM) ?
+			" and " : "",
+		type & ARCH_TIMER_TYPE_MEM ? "mmio" : "",
 		(unsigned long)arch_timer_rate / 1000000,
 		(unsigned long)(arch_timer_rate / 10000) % 100,
-		type & ARCH_CP15_TIMER ?
+		type & ARCH_TIMER_TYPE_CP15 ?
 			(arch_timer_uses_ppi == VIRT_PPI) ? "virt" : "phys" :
 			"",
-		type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  "/" : "",
-		type & ARCH_MEM_TIMER ?
+		type == (ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM) ? "/" : "",
+		type & ARCH_TIMER_TYPE_MEM ?
 			arch_timer_mem_use_virtual ? "virt" : "phys" :
 			"");
 }
@@ -899,7 +900,7 @@ static void __init arch_counter_register(unsigned type)
 	u64 start_count;
 
 	/* Register the CP15 based counter if we have one */
-	if (type & ARCH_CP15_TIMER) {
+	if (type & ARCH_TIMER_TYPE_CP15) {
 		if (IS_ENABLED(CONFIG_ARM64) || arch_timer_uses_ppi == VIRT_PPI)
 			arch_timer_read_counter = arch_counter_get_cntvct;
 		else
@@ -1062,7 +1063,7 @@ static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
 
 	t->base = base;
 	t->evt.irq = irq;
-	__arch_timer_setup(ARCH_MEM_TIMER, &t->evt);
+	__arch_timer_setup(ARCH_TIMER_TYPE_MEM, &t->evt);
 
 	if (arch_timer_mem_use_virtual)
 		func = arch_timer_handler_virt_mem;
@@ -1105,13 +1106,15 @@ static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
 
 static int __init arch_timer_common_init(void)
 {
-	unsigned mask = ARCH_CP15_TIMER | ARCH_MEM_TIMER;
+	unsigned mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM;
 
 	/* Wait until both nodes are probed if we have two timers */
 	if ((arch_timers_present & mask) != mask) {
-		if (arch_timer_needs_probing(ARCH_MEM_TIMER, arch_timer_mem_of_match))
+		if (arch_timer_needs_probing(ARCH_TIMER_TYPE_MEM,
+					     arch_timer_mem_of_match))
 			return 0;
-		if (arch_timer_needs_probing(ARCH_CP15_TIMER, arch_timer_of_match))
+		if (arch_timer_needs_probing(ARCH_TIMER_TYPE_CP15,
+					     arch_timer_of_match))
 			return 0;
 	}
 
@@ -1171,12 +1174,12 @@ static int __init arch_timer_of_init(struct device_node *np)
 {
 	int i;
 
-	if (arch_timers_present & ARCH_CP15_TIMER) {
+	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
 		pr_warn("multiple nodes in dt, skipping\n");
 		return 0;
 	}
 
-	arch_timers_present |= ARCH_CP15_TIMER;
+	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
 	for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
 		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
 
@@ -1211,7 +1214,7 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	unsigned int irq, ret = -EINVAL;
 	u32 cnttidr;
 
-	arch_timers_present |= ARCH_MEM_TIMER;
+	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
 	cntctlbase = of_iomap(np, 0);
 	if (!cntctlbase) {
 		pr_err("Can't find CNTCTLBase\n");
@@ -1311,14 +1314,14 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 {
 	struct acpi_table_gtdt *gtdt;
 
-	if (arch_timers_present & ARCH_CP15_TIMER) {
+	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
 		pr_warn("already initialized, skipping\n");
 		return -EINVAL;
 	}
 
 	gtdt = container_of(table, struct acpi_table_gtdt, header);
 
-	arch_timers_present |= ARCH_CP15_TIMER;
+	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
 
 	arch_timer_ppi[PHYS_SECURE_PPI] =
 		map_generic_timer_interrupt(gtdt->secure_el1_interrupt,
-- 
1.9.1

[PATCH 03/16] clocksource: arm_arch_timer: rename the PPI enum

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

In preparation for moving the PPI enum out into a header, rename the
enum and its constituent values these so they are namespaced w.r.t. the
arch timer. This will aid consistency and avoid potential name clashes
when this move occurs.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 82 ++++++++++++++++++------------------
 1 file changed, 42 insertions(+), 40 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 38bddb9..94e355b 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -70,19 +70,19 @@ struct arch_timer {
 
 static u32 arch_timer_rate;
 
-enum ppi_nr {
-	PHYS_SECURE_PPI,
-	PHYS_NONSECURE_PPI,
-	VIRT_PPI,
-	HYP_PPI,
-	MAX_TIMER_PPI
+enum arch_timer_ppi_nr {
+	ARCH_TIMER_PHYS_SECURE_PPI,
+	ARCH_TIMER_PHYS_NONSECURE_PPI,
+	ARCH_TIMER_VIRT_PPI,
+	ARCH_TIMER_HYP_PPI,
+	ARCH_TIMER_MAX_TIMER_PPI
 };
 
-static int arch_timer_ppi[MAX_TIMER_PPI];
+static int arch_timer_ppi[ARCH_TIMER_MAX_TIMER_PPI];
 
 static struct clock_event_device __percpu *arch_timer_evt;
 
-static enum ppi_nr arch_timer_uses_ppi = VIRT_PPI;
+static enum arch_timer_ppi_nr arch_timer_uses_ppi = ARCH_TIMER_VIRT_PPI;
 static bool arch_timer_c3stop;
 static bool arch_timer_mem_use_virtual;
 static bool arch_counter_suspend_stop;
@@ -694,14 +694,14 @@ static void __arch_timer_setup(unsigned type,
 		clk->cpumask = cpumask_of(smp_processor_id());
 		clk->irq = arch_timer_ppi[arch_timer_uses_ppi];
 		switch (arch_timer_uses_ppi) {
-		case VIRT_PPI:
+		case ARCH_TIMER_VIRT_PPI:
 			clk->set_state_shutdown = arch_timer_shutdown_virt;
 			clk->set_state_oneshot_stopped = arch_timer_shutdown_virt;
 			clk->set_next_event = arch_timer_set_next_event_virt;
 			break;
-		case PHYS_SECURE_PPI:
-		case PHYS_NONSECURE_PPI:
-		case HYP_PPI:
+		case ARCH_TIMER_PHYS_SECURE_PPI:
+		case ARCH_TIMER_PHYS_NONSECURE_PPI:
+		case ARCH_TIMER_HYP_PPI:
 			clk->set_state_shutdown = arch_timer_shutdown_phys;
 			clk->set_state_oneshot_stopped = arch_timer_shutdown_phys;
 			clk->set_next_event = arch_timer_set_next_event_phys;
@@ -789,8 +789,8 @@ static void arch_counter_set_user_access(void)
 
 static bool arch_timer_has_nonsecure_ppi(void)
 {
-	return (arch_timer_uses_ppi == PHYS_SECURE_PPI &&
-		arch_timer_ppi[PHYS_NONSECURE_PPI]);
+	return (arch_timer_uses_ppi == ARCH_TIMER_PHYS_SECURE_PPI &&
+		arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
 }
 
 static u32 check_ppi_trigger(int irq)
@@ -817,8 +817,9 @@ static int arch_timer_starting_cpu(unsigned int cpu)
 	enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], flags);
 
 	if (arch_timer_has_nonsecure_ppi()) {
-		flags = check_ppi_trigger(arch_timer_ppi[PHYS_NONSECURE_PPI]);
-		enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], flags);
+		flags = check_ppi_trigger(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
+		enable_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI],
+				  flags);
 	}
 
 	arch_counter_set_user_access();
@@ -862,7 +863,7 @@ static void arch_timer_banner(unsigned type)
 		(unsigned long)arch_timer_rate / 1000000,
 		(unsigned long)(arch_timer_rate / 10000) % 100,
 		type & ARCH_TIMER_TYPE_CP15 ?
-			(arch_timer_uses_ppi == VIRT_PPI) ? "virt" : "phys" :
+			(arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) ? "virt" : "phys" :
 			"",
 		type == (ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM) ? "/" : "",
 		type & ARCH_TIMER_TYPE_MEM ?
@@ -901,7 +902,8 @@ static void __init arch_counter_register(unsigned type)
 
 	/* Register the CP15 based counter if we have one */
 	if (type & ARCH_TIMER_TYPE_CP15) {
-		if (IS_ENABLED(CONFIG_ARM64) || arch_timer_uses_ppi == VIRT_PPI)
+		if (IS_ENABLED(CONFIG_ARM64) ||
+		    arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI)
 			arch_timer_read_counter = arch_counter_get_cntvct;
 		else
 			arch_timer_read_counter = arch_counter_get_cntpct;
@@ -930,7 +932,7 @@ static void arch_timer_stop(struct clock_event_device *clk)
 
 	disable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi]);
 	if (arch_timer_has_nonsecure_ppi())
-		disable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI]);
+		disable_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
 
 	clk->set_state_shutdown(clk);
 }
@@ -993,24 +995,24 @@ static int __init arch_timer_register(void)
 
 	ppi = arch_timer_ppi[arch_timer_uses_ppi];
 	switch (arch_timer_uses_ppi) {
-	case VIRT_PPI:
+	case ARCH_TIMER_VIRT_PPI:
 		err = request_percpu_irq(ppi, arch_timer_handler_virt,
 					 "arch_timer", arch_timer_evt);
 		break;
-	case PHYS_SECURE_PPI:
-	case PHYS_NONSECURE_PPI:
+	case ARCH_TIMER_PHYS_SECURE_PPI:
+	case ARCH_TIMER_PHYS_NONSECURE_PPI:
 		err = request_percpu_irq(ppi, arch_timer_handler_phys,
 					 "arch_timer", arch_timer_evt);
-		if (!err && arch_timer_ppi[PHYS_NONSECURE_PPI]) {
-			ppi = arch_timer_ppi[PHYS_NONSECURE_PPI];
+		if (!err && arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]) {
+			ppi = arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI];
 			err = request_percpu_irq(ppi, arch_timer_handler_phys,
 						 "arch_timer", arch_timer_evt);
 			if (err)
-				free_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI],
+				free_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI],
 						arch_timer_evt);
 		}
 		break;
-	case HYP_PPI:
+	case ARCH_TIMER_HYP_PPI:
 		err = request_percpu_irq(ppi, arch_timer_handler_phys,
 					 "arch_timer", arch_timer_evt);
 		break;
@@ -1042,7 +1044,7 @@ static int __init arch_timer_register(void)
 out_unreg_notify:
 	free_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], arch_timer_evt);
 	if (arch_timer_has_nonsecure_ppi())
-		free_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI],
+		free_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI],
 				arch_timer_evt);
 
 out_free:
@@ -1139,16 +1141,16 @@ static int __init arch_timer_init(void)
 	 * their CNTHP_*_EL2 counterparts, and use a different PPI
 	 * number.
 	 */
-	if (is_hyp_mode_available() || !arch_timer_ppi[VIRT_PPI]) {
+	if (is_hyp_mode_available() || !arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) {
 		bool has_ppi;
 
 		if (is_kernel_in_hyp_mode()) {
-			arch_timer_uses_ppi = HYP_PPI;
-			has_ppi = !!arch_timer_ppi[HYP_PPI];
+			arch_timer_uses_ppi = ARCH_TIMER_HYP_PPI;
+			has_ppi = !!arch_timer_ppi[ARCH_TIMER_HYP_PPI];
 		} else {
-			arch_timer_uses_ppi = PHYS_SECURE_PPI;
-			has_ppi = (!!arch_timer_ppi[PHYS_SECURE_PPI] ||
-				   !!arch_timer_ppi[PHYS_NONSECURE_PPI]);
+			arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
+			has_ppi = (!!arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI] ||
+				   !!arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
 		}
 
 		if (!has_ppi) {
@@ -1165,7 +1167,7 @@ static int __init arch_timer_init(void)
 	if (ret)
 		return ret;
 
-	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[VIRT_PPI];
+	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];
 
 	return 0;
 }
@@ -1180,7 +1182,7 @@ static int __init arch_timer_of_init(struct device_node *np)
 	}
 
 	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
-	for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
+	for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++)
 		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
 
 	arch_timer_detect_rate(NULL, np);
@@ -1196,7 +1198,7 @@ static int __init arch_timer_of_init(struct device_node *np)
 	 */
 	if (IS_ENABLED(CONFIG_ARM) &&
 	    of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
-		arch_timer_uses_ppi = PHYS_SECURE_PPI;
+		arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
 
 	/* On some systems, the counter stops ticking when in suspend. */
 	arch_counter_suspend_stop = of_property_read_bool(np,
@@ -1323,19 +1325,19 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 
 	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
 
-	arch_timer_ppi[PHYS_SECURE_PPI] =
+	arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI] =
 		map_generic_timer_interrupt(gtdt->secure_el1_interrupt,
 		gtdt->secure_el1_flags);
 
-	arch_timer_ppi[PHYS_NONSECURE_PPI] =
+	arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI] =
 		map_generic_timer_interrupt(gtdt->non_secure_el1_interrupt,
 		gtdt->non_secure_el1_flags);
 
-	arch_timer_ppi[VIRT_PPI] =
+	arch_timer_ppi[ARCH_TIMER_VIRT_PPI] =
 		map_generic_timer_interrupt(gtdt->virtual_timer_interrupt,
 		gtdt->virtual_timer_flags);
 
-	arch_timer_ppi[HYP_PPI] =
+	arch_timer_ppi[ARCH_TIMER_HYP_PPI] =
 		map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
 		gtdt->non_secure_el2_flags);
 
-- 
1.9.1

[PATCH 04/16] clocksource: arm_arch_timer: move enums and defines to header file

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

To support the arm_arch_timer via ACPI we need to share defines and enums
between the driver and the ACPI parser code.
So we split out the relevant defines and enums into arm_arch_timer.h.

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 11 -----------
 include/clocksource/arm_arch_timer.h | 12 ++++++++++++
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 94e355b..04218c1 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -55,8 +55,6 @@
 #define CNTV_TVAL	0x38
 #define CNTV_CTL	0x3c
 
-#define ARCH_TIMER_TYPE_CP15		BIT(0)
-#define ARCH_TIMER_TYPE_MEM		BIT(1)
 static unsigned arch_timers_present __initdata;
 
 static void __iomem *arch_counter_base;
@@ -69,15 +67,6 @@ struct arch_timer {
 #define to_arch_timer(e) container_of(e, struct arch_timer, evt)
 
 static u32 arch_timer_rate;
-
-enum arch_timer_ppi_nr {
-	ARCH_TIMER_PHYS_SECURE_PPI,
-	ARCH_TIMER_PHYS_NONSECURE_PPI,
-	ARCH_TIMER_VIRT_PPI,
-	ARCH_TIMER_HYP_PPI,
-	ARCH_TIMER_MAX_TIMER_PPI
-};
-
 static int arch_timer_ppi[ARCH_TIMER_MAX_TIMER_PPI];
 
 static struct clock_event_device __percpu *arch_timer_evt;
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index caedb74..b898637 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -16,9 +16,13 @@
 #ifndef __CLKSOURCE_ARM_ARCH_TIMER_H
 #define __CLKSOURCE_ARM_ARCH_TIMER_H
 
+#include <linux/bitops.h>
 #include <linux/timecounter.h>
 #include <linux/types.h>
 
+#define ARCH_TIMER_TYPE_CP15		BIT(0)
+#define ARCH_TIMER_TYPE_MEM		BIT(1)
+
 #define ARCH_TIMER_CTRL_ENABLE		(1 << 0)
 #define ARCH_TIMER_CTRL_IT_MASK		(1 << 1)
 #define ARCH_TIMER_CTRL_IT_STAT		(1 << 2)
@@ -34,6 +38,14 @@ enum arch_timer_reg {
 	ARCH_TIMER_REG_TVAL,
 };
 
+enum arch_timer_ppi_nr {
+	ARCH_TIMER_PHYS_SECURE_PPI,
+	ARCH_TIMER_PHYS_NONSECURE_PPI,
+	ARCH_TIMER_VIRT_PPI,
+	ARCH_TIMER_HYP_PPI,
+	ARCH_TIMER_MAX_TIMER_PPI
+};
+
 #define ARCH_TIMER_PHYS_ACCESS		0
 #define ARCH_TIMER_VIRT_ACCESS		1
 #define ARCH_TIMER_MEM_PHYS_ACCESS	2
-- 
1.9.1

[PATCH 05/16] clocksource: arm_arch_timer: add a new enum for spi type

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

This patch add a new enum "arch_timer_spi_nr" and use it in the driver.
Just for code's readability, no functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 4 ++--
 include/clocksource/arm_arch_timer.h | 6 ++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 04218c1..15059c9 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1258,9 +1258,9 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	}
 
 	if (arch_timer_mem_use_virtual)
-		irq = irq_of_parse_and_map(best_frame, 1);
+		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_VIRT_SPI);
 	else
-		irq = irq_of_parse_and_map(best_frame, 0);
+		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_PHYS_SPI);
 
 	ret = -EINVAL;
 	if (!irq) {
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index b898637..4a98c06 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -46,6 +46,12 @@ enum arch_timer_ppi_nr {
 	ARCH_TIMER_MAX_TIMER_PPI
 };
 
+enum arch_timer_spi_nr {
+	ARCH_TIMER_PHYS_SPI,
+	ARCH_TIMER_VIRT_SPI,
+	ARCH_TIMER_MAX_TIMER_SPI
+};
+
 #define ARCH_TIMER_PHYS_ACCESS		0
 #define ARCH_TIMER_VIRT_ACCESS		1
 #define ARCH_TIMER_MEM_PHYS_ACCESS	2
-- 
1.9.1

[PATCH 06/16] clocksource: arm_arch_timer: rework PPI selection

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

Currently, the arch timer driver uses ARCH_TIMER_PHYS_SECURE_PPI to mean
the driver will use the secure PPI *and* potentially also use the
non-secure PPI. This is somewhat confusing.

For arm64 it never makes sense to use the secure PPI, but we do anyway,
inheriting this behaviour from 32-bit arm. For ACPI, we may not even
have a valid secure PPI, so we need to be able to only request the
non-secure PPI.

To that end, this patch reworks the timer driver so that we can request
the non-secure PPI alone. The PPI selection is split out into a new
function, arch_timer_select_ppi(), and verification of the selected PPI
is shifted out to callers (as DT may select the PPI by other means and
must handle this anyway).

We now consistently use arch_timer_has_nonsecure_ppi() to determine
whether we must manage a non-secure PPI *in addition* to a secure PPI.
When we only have a non-secure PPI, this returns false.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 77 +++++++++++++++++++++---------------
 1 file changed, 46 insertions(+), 31 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 15059c9..94de018 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -992,7 +992,7 @@ static int __init arch_timer_register(void)
 	case ARCH_TIMER_PHYS_NONSECURE_PPI:
 		err = request_percpu_irq(ppi, arch_timer_handler_phys,
 					 "arch_timer", arch_timer_evt);
-		if (!err && arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]) {
+		if (!err && arch_timer_has_nonsecure_ppi()) {
 			ppi = arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI];
 			err = request_percpu_irq(ppi, arch_timer_handler_phys,
 						 "arch_timer", arch_timer_evt);
@@ -1114,39 +1114,41 @@ static int __init arch_timer_common_init(void)
 	return arch_timer_arch_init();
 }
 
-static int __init arch_timer_init(void)
+/**
+ * arch_timer_select_ppi() - Select suitable PPI for the current system.
+ *
+ * If HYP mode is available, we know that the physical timer
+ * has been configured to be accessible from PL1. Use it, so
+ * that a guest can use the virtual timer instead.
+ *
+ * On ARMv8.1 with VH extensions, the kernel runs in HYP. VHE
+ * accesses to CNTP_*_EL1 registers are silently redirected to
+ * their CNTHP_*_EL2 counterparts, and use a different PPI
+ * number.
+ *
+ * If no interrupt provided for virtual timer, we'll have to
+ * stick to the physical timer. It'd better be accessible...
+ * For arm64 we never use the secure interrupt.
+ *
+ * Return: a suitable PPI type for the current system.
+ */
+static enum arch_timer_ppi_nr __init arch_timer_select_ppi(void)
 {
-	int ret;
-	/*
-	 * If HYP mode is available, we know that the physical timer
-	 * has been configured to be accessible from PL1. Use it, so
-	 * that a guest can use the virtual timer instead.
-	 *
-	 * If no interrupt provided for virtual timer, we'll have to
-	 * stick to the physical timer. It'd better be accessible...
-	 *
-	 * On ARMv8.1 with VH extensions, the kernel runs in HYP. VHE
-	 * accesses to CNTP_*_EL1 registers are silently redirected to
-	 * their CNTHP_*_EL2 counterparts, and use a different PPI
-	 * number.
-	 */
-	if (is_hyp_mode_available() || !arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) {
-		bool has_ppi;
+	if (is_kernel_in_hyp_mode())
+		return ARCH_TIMER_HYP_PPI;
 
-		if (is_kernel_in_hyp_mode()) {
-			arch_timer_uses_ppi = ARCH_TIMER_HYP_PPI;
-			has_ppi = !!arch_timer_ppi[ARCH_TIMER_HYP_PPI];
-		} else {
-			arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
-			has_ppi = (!!arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI] ||
-				   !!arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
-		}
+	if (!is_hyp_mode_available() && arch_timer_ppi[ARCH_TIMER_VIRT_PPI])
+		return ARCH_TIMER_VIRT_PPI;
 
-		if (!has_ppi) {
-			pr_warn("No interrupt available, giving up\n");
-			return -EINVAL;
-		}
-	}
+	if (IS_ENABLED(CONFIG_ARM64))
+		return ARCH_TIMER_PHYS_NONSECURE_PPI;
+
+	return ARCH_TIMER_PHYS_SECURE_PPI;
+}
+
+static int __init arch_timer_init(void)
+{
+	int ret;
 
 	ret = arch_timer_register();
 	if (ret)
@@ -1188,6 +1190,13 @@ static int __init arch_timer_of_init(struct device_node *np)
 	if (IS_ENABLED(CONFIG_ARM) &&
 	    of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
 		arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
+	else
+		arch_timer_uses_ppi = arch_timer_select_ppi();
+
+	if (!arch_timer_ppi[arch_timer_uses_ppi]) {
+		pr_err("No interrupt available, giving up\n");
+		return -EINVAL;
+	}
 
 	/* On some systems, the counter stops ticking when in suspend. */
 	arch_counter_suspend_stop = of_property_read_bool(np,
@@ -1333,6 +1342,12 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 	/* Get the frequency from CNTFRQ */
 	arch_timer_detect_rate(NULL, NULL);
 
+	arch_timer_uses_ppi = arch_timer_select_ppi();
+	if (!arch_timer_ppi[arch_timer_uses_ppi]) {
+		pr_err("No interrupt available, giving up\n");
+		return -EINVAL;
+	}
+
 	/* Always-on capability */
 	arch_timer_c3stop = !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON);
 
-- 
1.9.1

[PATCH 07/16] clocksource: arm_arch_timer: split dt-only rate handling

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

For historical reasons, rate detection when probing via DT is somewhat
convoluted. We tried to package this up in arch_timer_detect_rate(), but
with the addition of ACPI worse, and gets in the way of stringent rate
checking when ACPI is used.

This patch makes arch_timer_detect_rate() specific to DT, ripping out
ACPI logic. In preparation for rework of the MMIO timer probing, the
reading of the relevant CNTFRQ register is factored out to callers. The
function is then renamed to arch_timer_of_configure_rate(), which better
represents its new place in the world.

Comments are added in the DT and ACPI probe paths to explain this.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 41 ++++++++++++++++++++----------------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 94de018..02c5cb8 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -818,24 +818,19 @@ static int arch_timer_starting_cpu(unsigned int cpu)
 	return 0;
 }
 
-static void
-arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
+/*
+ * For historical reasons, when probing with DT we use whichever (non-zero)
+ * rate was probed first, and don't verify that others match. If the first node
+ * probed has a clock-frequency property, this overrides the HW register.
+ */
+static void arch_timer_of_configure_rate(u32 rate, struct device_node *np)
 {
 	/* Who has more than one independent system counter? */
 	if (arch_timer_rate)
 		return;
 
-	/*
-	 * Try to determine the frequency from the device tree or CNTFRQ,
-	 * if ACPI is enabled, get the frequency from CNTFRQ ONLY.
-	 */
-	if (!acpi_disabled ||
-	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) {
-		if (cntbase)
-			arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
-		else
-			arch_timer_rate = arch_timer_get_cntfrq();
-	}
+	if (of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
+		arch_timer_rate = rate;
 
 	/* Check the timer frequency. */
 	if (arch_timer_rate == 0)
@@ -1166,6 +1161,7 @@ static int __init arch_timer_init(void)
 static int __init arch_timer_of_init(struct device_node *np)
 {
 	int i;
+	u32 rate;
 
 	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
 		pr_warn("multiple nodes in dt, skipping\n");
@@ -1176,7 +1172,8 @@ static int __init arch_timer_of_init(struct device_node *np)
 	for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++)
 		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
 
-	arch_timer_detect_rate(NULL, np);
+	rate = arch_timer_get_cntfrq;
+	arch_timer_of_configure_rate(rate, np);
 
 	arch_timer_c3stop = !of_property_read_bool(np, "always-on");
 
@@ -1212,7 +1209,7 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	struct device_node *frame, *best_frame = NULL;
 	void __iomem *cntctlbase, *base;
 	unsigned int irq, ret = -EINVAL;
-	u32 cnttidr;
+	u32 cnttidr, rate;
 
 	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
 	cntctlbase = of_iomap(np, 0);
@@ -1278,7 +1275,8 @@ static int __init arch_timer_mem_init(struct device_node *np)
 		goto out;
 	}
 
-	arch_timer_detect_rate(base, np);
+	rate = readl(base + CNTFRQ);
+	arch_timer_of_configure_rate(rate, np);
 	ret = arch_timer_mem_register(base, irq);
 	if (ret)
 		goto out;
@@ -1339,8 +1337,15 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 		map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
 		gtdt->non_secure_el2_flags);
 
-	/* Get the frequency from CNTFRQ */
-	arch_timer_detect_rate(NULL, NULL);
+	/*
+	 * When probing via ACPI, we have no mechanism to override the sysreg
+	 * CNTFRQ value. This *must* be correct.
+	 */
+	arch_timer_rate = arch_timer_get_cntfrq();
+	if (!arch_timer_rate) {
+		pr_err(FW_BUG "frequency not available.\n");
+		return -EINVAL;
+	}
 
 	arch_timer_uses_ppi = arch_timer_select_ppi();
 	if (!arch_timer_ppi[arch_timer_uses_ppi]) {
-- 
1.9.1

[PATCH 08/16] clocksource: arm_arch_timer: refactor arch_timer_needs_probing

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

When booting with DT, it's possible for timer nodes to be probed in any
order. Some common initialisation needs to occur after all nodes have
been probed, and arch_timer_common_init() has code to detect when this
has happened.

This logic is DT-specific, and it would be best to factor it out of the
common code that will be shared with ACPI.

This patch folds this into the existing arch_timer_needs_probing(),
which is renamed to arch_timer_needs_of_probing(), and no longer takes
any arguments. This is only called when using DT, and not when using
ACPI, which will have a deterministic probe order.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 34 +++++++++++++++++++---------------
 1 file changed, 19 insertions(+), 15 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 02c5cb8..e38f4d4 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1076,15 +1076,28 @@ static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
 	{},
 };
 
-static bool __init
-arch_timer_needs_probing(int type, const struct of_device_id *matches)
+static bool __init arch_timer_needs_of_probing(void)
 {
 	struct device_node *dn;
 	bool needs_probing = false;
+	unsigned int mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM;
 
-	dn = of_find_matching_node(NULL, matches);
-	if (dn && of_device_is_available(dn) && !(arch_timers_present & type))
+	/* We have two timers, and both device-tree nodes are probed. */
+	if ((arch_timers_present & mask) == mask)
+		return false;
+
+	/*
+	 * Only one type of timer is probed,
+	 * check if we have another type of timer node in device-tree.
+	 */
+	if (arch_timers_present & ARCH_TIMER_TYPE_CP15)
+		dn = of_find_matching_node(NULL, arch_timer_mem_of_match);
+	else
+		dn = of_find_matching_node(NULL, arch_timer_of_match);
+
+	if (dn && of_device_is_available(dn))
 		needs_probing = true;
+
 	of_node_put(dn);
 
 	return needs_probing;
@@ -1092,17 +1105,8 @@ static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
 
 static int __init arch_timer_common_init(void)
 {
-	unsigned mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM;
-
-	/* Wait until both nodes are probed if we have two timers */
-	if ((arch_timers_present & mask) != mask) {
-		if (arch_timer_needs_probing(ARCH_TIMER_TYPE_MEM,
-					     arch_timer_mem_of_match))
-			return 0;
-		if (arch_timer_needs_probing(ARCH_TIMER_TYPE_CP15,
-					     arch_timer_of_match))
-			return 0;
-	}
+	if (acpi_disabled && arch_timer_needs_of_probing())
+		return 0;
 
 	arch_timer_banner(arch_timers_present);
 	arch_counter_register(arch_timers_present);
-- 
1.9.1

[PATCH 09/16] clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init call

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

To cleanly split code paths specific to ACPI or DT at a higher level,
this patch removes arch_timer_init(), folding the relevant
parts of its logic into existing callers.

This pathes the way for further rework, and saves a few lines.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 46 ++++++++++++++++--------------------
 1 file changed, 21 insertions(+), 25 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index e38f4d4..ac6fd00 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1105,9 +1105,6 @@ static bool __init arch_timer_needs_of_probing(void)
 
 static int __init arch_timer_common_init(void)
 {
-	if (acpi_disabled && arch_timer_needs_of_probing())
-		return 0;
-
 	arch_timer_banner(arch_timers_present);
 	arch_counter_register(arch_timers_present);
 	return arch_timer_arch_init();
@@ -1145,26 +1142,9 @@ static enum arch_timer_ppi_nr __init arch_timer_select_ppi(void)
 	return ARCH_TIMER_PHYS_SECURE_PPI;
 }
 
-static int __init arch_timer_init(void)
-{
-	int ret;
-
-	ret = arch_timer_register();
-	if (ret)
-		return ret;
-
-	ret = arch_timer_common_init();
-	if (ret)
-		return ret;
-
-	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];
-
-	return 0;
-}
-
 static int __init arch_timer_of_init(struct device_node *np)
 {
-	int i;
+	int i, ret;
 	u32 rate;
 
 	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
@@ -1176,6 +1156,8 @@ static int __init arch_timer_of_init(struct device_node *np)
 	for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++)
 		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
 
+	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];
+
 	rate = arch_timer_get_cntfrq;
 	arch_timer_of_configure_rate(rate, np);
 
@@ -1203,7 +1185,14 @@ static int __init arch_timer_of_init(struct device_node *np)
 	arch_counter_suspend_stop = of_property_read_bool(np,
 							 "arm,no-tick-in-suspend");
 
-	return arch_timer_init();
+	ret = arch_timer_register();
+	if (ret)
+		return ret;
+
+	if (arch_timer_needs_of_probing())
+		return 0;
+
+	return arch_timer_common_init();
 }
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
 CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
@@ -1285,7 +1274,8 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	if (ret)
 		goto out;
 
-	return arch_timer_common_init();
+	if (!arch_timer_needs_of_probing())
+		ret = arch_timer_common_init();
 out:
 	iounmap(cntctlbase);
 	of_node_put(best_frame);
@@ -1314,6 +1304,7 @@ static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)
 /* Initialize per-processor generic timer */
 static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 {
+	int ret;
 	struct acpi_table_gtdt *gtdt;
 
 	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
@@ -1341,6 +1332,8 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 		map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
 		gtdt->non_secure_el2_flags);
 
+	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];
+
 	/*
 	 * When probing via ACPI, we have no mechanism to override the sysreg
 	 * CNTFRQ value. This *must* be correct.
@@ -1363,8 +1356,11 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 	/* Check for globally applicable workarounds */
 	arch_timer_check_ool_workaround(ate_match_acpi_oem_info, table);
 
-	arch_timer_init();
-	return 0;
+	ret = arch_timer_register();
+	if (ret)
+		return ret;
+
+	return arch_timer_common_init();
 }
 CLOCKSOURCE_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
 #endif
-- 
1.9.1

[PATCH 10/16] clocksource: arm_arch_timer: add structs to describe MMIO timer

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

In preparation for ACPI GTDT support, this patch adds structs to
describe the MMIO timers indepedent of the firmware interface.

Subsequent patches will use these to split the FW/HW probing logic, so
that the HW probing logic can be shared by ACPI and DT.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 include/clocksource/arm_arch_timer.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index 4a98c06..cc805b7 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -57,6 +57,8 @@ enum arch_timer_spi_nr {
 #define ARCH_TIMER_MEM_PHYS_ACCESS	2
 #define ARCH_TIMER_MEM_VIRT_ACCESS	3
 
+#define ARCH_TIMER_MEM_MAX_FRAMES	8
+
 #define ARCH_TIMER_USR_PCT_ACCESS_EN	(1 << 0) /* physical counter */
 #define ARCH_TIMER_USR_VCT_ACCESS_EN	(1 << 1) /* virtual counter */
 #define ARCH_TIMER_VIRT_EVT_EN		(1 << 2)
@@ -72,6 +74,20 @@ struct arch_timer_kvm_info {
 	int virtual_irq;
 };
 
+struct arch_timer_mem_frame {
+	bool valid;
+	phys_addr_t cntbase;
+	size_t size;
+	int phys_irq;
+	int virt_irq;
+};
+
+struct arch_timer_mem {
+	phys_addr_t cntctlbase;
+	size_t size;
+	struct arch_timer_mem_frame frame[ARCH_TIMER_MEM_MAX_FRAMES];
+};
+
 #ifdef CONFIG_ARM_ARCH_TIMER
 
 extern u32 arch_timer_get_rate(void);
-- 
1.9.1

[PATCH 11/16] clocksource: arm_arch_timer: split MMIO timer probing.

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

Currently the code to probe MMIO architected timers mixes DT parsing with
actual poking of hardware. This makes the code harder than necessary to
understand, and makes it difficult to add support for probing via ACPI.

This patch splits the DT parsing from HW probing. The DT parsing now
lives in arch_timer_mem_of_init(), which fills in an arch_timer_mem
structure that it hands to probing functions that can be reused for ACPI
support.

Since the rate detection logic will be slight different when using ACPI,
the probing is performed as a number of steps. This results in more code
for the moment, and some arguably redundant work, but simplifies matters
considerably when ACPI support is added.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
[Mark: refactor the probing split]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 189 +++++++++++++++++++++++++++--------
 1 file changed, 145 insertions(+), 44 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index ac6fd00..d87c403 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1158,7 +1158,7 @@ static int __init arch_timer_of_init(struct device_node *np)
 
 	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];
 
-	rate = arch_timer_get_cntfrq;
+	rate = arch_timer_get_cntfrq();
 	arch_timer_of_configure_rate(rate, np);
 
 	arch_timer_c3stop = !of_property_read_bool(np, "always-on");
@@ -1197,18 +1197,38 @@ static int __init arch_timer_of_init(struct device_node *np)
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
 CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
 
-static int __init arch_timer_mem_init(struct device_node *np)
+static u32 __init
+arch_timer_mem_frame_get_cntfrq(struct arch_timer_mem_frame *frame)
 {
-	struct device_node *frame, *best_frame = NULL;
-	void __iomem *cntctlbase, *base;
-	unsigned int irq, ret = -EINVAL;
-	u32 cnttidr, rate;
+	void __iomem *base;
+	u32 rate;
 
-	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
-	cntctlbase = of_iomap(np, 0);
+	base = ioremap(frame->cntbase, frame->size);
+	if (!base) {
+		pr_err("Unable to map frame @ %pa\n", &frame->cntbase);
+		return 0;
+	}
+
+	rate = readl_relaxed(frame + CNTFRQ);
+
+	iounmap(frame);
+
+	return rate;
+}
+
+static struct arch_timer_mem_frame * __init
+arch_timer_mem_find_best_frame(struct arch_timer_mem *timer_mem)
+{
+	struct arch_timer_mem_frame *frame, *best_frame = NULL;
+	void __iomem *cntctlbase;
+	u32 cnttidr;
+	int i;
+
+	cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size);
 	if (!cntctlbase) {
-		pr_err("Can't find CNTCTLBase\n");
-		return -ENXIO;
+		pr_err("Can't map CNTCTLBase @ %pa\n",
+			&timer_mem->cntctlbase);
+		return NULL;
 	}
 
 	cnttidr = readl_relaxed(cntctlbase + CNTTIDR);
@@ -1217,25 +1237,20 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	 * Try to find a virtual capable frame. Otherwise fall back to a
 	 * physical capable frame.
 	 */
-	for_each_available_child_of_node(np, frame) {
-		int n;
-		u32 cntacr;
+	for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) {
+		u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
+			     CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
 
-		if (of_property_read_u32(frame, "frame-number", &n)) {
-			pr_err("Missing frame-number\n");
-			of_node_put(frame);
-			goto out;
-		}
+		frame = &timer_mem->frame[i];
+		if (!frame->valid)
+			continue;
 
 		/* Try enabling everything, and see what sticks */
-		cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
-			 CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
-		writel_relaxed(cntacr, cntctlbase + CNTACR(n));
-		cntacr = readl_relaxed(cntctlbase + CNTACR(n));
+		writel_relaxed(cntacr, cntctlbase + CNTACR(i));
+		cntacr = readl_relaxed(cntctlbase + CNTACR(i));
 
-		if ((cnttidr & CNTTIDR_VIRT(n)) &&
+		if ((cnttidr & CNTTIDR_VIRT(i)) &&
 		    !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) {
-			of_node_put(best_frame);
 			best_frame = frame;
 			arch_timer_mem_use_virtual = true;
 			break;
@@ -1244,45 +1259,131 @@ static int __init arch_timer_mem_init(struct device_node *np)
 		if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
 			continue;
 
-		of_node_put(best_frame);
-		best_frame = of_node_get(frame);
+		best_frame = frame;
 	}
 
-	ret= -ENXIO;
-	base = arch_counter_base = of_io_request_and_map(best_frame, 0,
-							 "arch_mem_timer");
-	if (IS_ERR(base)) {
-		pr_err("Can't map frame's registers\n");
-		goto out;
-	}
+	iounmap(cntctlbase);
+
+	if (!best_frame)
+		pr_err("Unable to find a suitable frame in timer @ %pa\n",
+			&timer_mem->cntctlbase);
+
+	return frame;
+}
+
+static int __init
+arch_timer_mem_frame_register(struct arch_timer_mem_frame *frame)
+{
+	void __iomem *base;
+	int ret, irq = 0;
 
 	if (arch_timer_mem_use_virtual)
-		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_VIRT_SPI);
+		irq = frame->virt_irq;
 	else
-		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_PHYS_SPI);
+		irq = frame->phys_irq;
 
-	ret = -EINVAL;
 	if (!irq) {
 		pr_err("Frame missing %s irq.\n",
 		       arch_timer_mem_use_virtual ? "virt" : "phys");
-		goto out;
+		return -EINVAL;
+	}
+
+	if (!request_mem_region(frame->cntbase, frame->size,
+				"arch_mem_timer"))
+		return -EBUSY;
+
+	base = ioremap(frame->cntbase, frame->size);
+	if (!base) {
+		pr_err("Can't map frame's registers\n");
+		return -ENXIO;
 	}
 
-	rate = readl(base + CNTFRQ);
-	arch_timer_of_configure_rate(rate, np);
 	ret = arch_timer_mem_register(base, irq);
-	if (ret)
+	if (ret) {
+		iounmap(base);
+		return ret;
+	}
+
+	arch_counter_base = base;
+	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
+
+	return 0;
+}
+
+static int __init arch_timer_mem_of_init(struct device_node *np)
+{
+	struct arch_timer_mem *timer_mem;
+	struct arch_timer_mem_frame *frame;
+	struct device_node *frame_node;
+	struct resource res;
+	int ret = -EINVAL;
+	u32 rate;
+
+	timer_mem = kzalloc(sizeof(*timer_mem), GFP_KERNEL);
+	if (!timer_mem)
+		return -ENOMEM;
+
+	if (of_address_to_resource(np, 0, &res))
 		goto out;
+	timer_mem->cntctlbase = res.start;
+	timer_mem->size = resource_size(&res);
 
-	if (!arch_timer_needs_of_probing())
+	for_each_available_child_of_node(np, frame_node) {
+		u32 n;
+		struct arch_timer_mem_frame *frame;
+
+		if (of_property_read_u32(frame_node, "frame-number", &n)) {
+			pr_err(FW_BUG "Missing frame-number.\n");
+			of_node_put(frame_node);
+			goto out;
+		}
+		if (n >= ARCH_TIMER_MEM_MAX_FRAMES) {
+			pr_err(FW_BUG "Wrong frame-number, only 0-%u are permitted.\n",
+			       ARCH_TIMER_MEM_MAX_FRAMES - 1);
+			of_node_put(frame_node);
+			goto out;
+		}
+		frame = &timer_mem->frame[n];
+
+		if (frame->valid) {
+			pr_err(FW_BUG "Duplicated frame-number.\n");
+			of_node_put(frame_node);
+			goto out;
+		}
+
+		if (of_address_to_resource(frame_node, 0, &res)) {
+			of_node_put(frame_node);
+			goto out;
+		}
+		frame->cntbase = res.start;
+		frame->size = resource_size(&res);
+
+		frame->virt_irq = irq_of_parse_and_map(frame_node,
+						       ARCH_TIMER_VIRT_SPI);
+		frame->phys_irq = irq_of_parse_and_map(frame_node,
+						       ARCH_TIMER_PHYS_SPI);
+
+		frame->valid = true;
+	}
+
+	frame = arch_timer_mem_find_best_frame(timer_mem);
+	if (!frame) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	rate = arch_timer_mem_frame_get_cntfrq(frame);
+	arch_timer_of_configure_rate(rate, np);
+
+	ret = arch_timer_mem_frame_register(frame);
+	if (!ret && !arch_timer_needs_of_probing())
 		ret = arch_timer_common_init();
 out:
-	iounmap(cntctlbase);
-	of_node_put(best_frame);
+	kfree(timer_mem);
 	return ret;
 }
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
-		       arch_timer_mem_init);
+		       arch_timer_mem_of_init);
 
 #ifdef CONFIG_ACPI
 static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)
-- 
1.9.1

[PATCH 12/16] acpi/arm64: Add GTDT table parse driver

[Mark Rutland]

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>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 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(+)
 create mode 100644 drivers/acpi/arm64/gtdt.c

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..3d95af8
--- /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: Secure state is not managed by the kernel on ARM64 systems.
+ * 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: 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 false;
+}
+
+/**
+ * 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;
+	}
+
+	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;
+
+	return 0;
+}
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
-- 
1.9.1

[PATCH 13/16] clocksource: arm_arch_timer: simplify ACPI support code.

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

The patch update arm_arch_timer driver to use the function
provided by the new GTDT driver of ACPI.
By this way, arm_arch_timer.c can be simplified, and separate
all the ACPI GTDT knowledge from this timer driver.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 40 +++++++++---------------------------
 1 file changed, 10 insertions(+), 30 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index d87c403..e398228 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1385,53 +1385,33 @@ static int __init arch_timer_mem_of_init(struct device_node *np)
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
 		       arch_timer_mem_of_init);
 
-#ifdef CONFIG_ACPI
-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);
-}
-
+#ifdef CONFIG_ACPI_GTDT
 /* Initialize per-processor generic timer */
 static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 {
 	int ret;
-	struct acpi_table_gtdt *gtdt;
 
 	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
 		pr_warn("already initialized, skipping\n");
 		return -EINVAL;
 	}
 
-	gtdt = container_of(table, struct acpi_table_gtdt, header);
-
 	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
 
-	arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI] =
-		map_generic_timer_interrupt(gtdt->secure_el1_interrupt,
-		gtdt->secure_el1_flags);
+	ret = acpi_gtdt_init(table, NULL);
+	if (ret) {
+		pr_err("Failed to init GTDT table.\n");
+		return ret;
+	}
 
 	arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI] =
-		map_generic_timer_interrupt(gtdt->non_secure_el1_interrupt,
-		gtdt->non_secure_el1_flags);
+		acpi_gtdt_map_ppi(ARCH_TIMER_PHYS_NONSECURE_PPI);
 
 	arch_timer_ppi[ARCH_TIMER_VIRT_PPI] =
-		map_generic_timer_interrupt(gtdt->virtual_timer_interrupt,
-		gtdt->virtual_timer_flags);
+		acpi_gtdt_map_ppi(ARCH_TIMER_VIRT_PPI);
 
 	arch_timer_ppi[ARCH_TIMER_HYP_PPI] =
-		map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
-		gtdt->non_secure_el2_flags);
+		acpi_gtdt_map_ppi(ARCH_TIMER_HYP_PPI);
 
 	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];
 
@@ -1452,7 +1432,7 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 	}
 
 	/* Always-on capability */
-	arch_timer_c3stop = !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON);
+	arch_timer_c3stop = acpi_gtdt_c3stop(arch_timer_uses_ppi);
 
 	/* Check for globally applicable workarounds */
 	arch_timer_check_ool_workaround(ate_match_acpi_oem_info, table);
-- 
1.9.1

[PATCH 14/16] acpi/arm64: Add memory-mapped timer support in GTDT driver

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

On platforms booting with ACPI, architected memory-mapped timers'
configuration data is provided by firmware through the ACPI GTDT
static table.

The clocksource architected timer kernel driver requires a firmware
interface to collect timer configuration and configure its driver.
this infrastructure is present for device tree systems, but it is
missing on systems booting with ACPI.

Implement the kernel infrastructure required to parse the static
ACPI GTDT table so that the architected timer clocksource driver can
make use of it on systems booting with ACPI, therefore enabling
the corresponding timers configuration.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
[Mark: restructure error handling]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/acpi/arm64/gtdt.c | 157 ++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/acpi.h      |   1 +
 2 files changed, 158 insertions(+)

diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c
index 3d95af8..b904667 100644
--- a/drivers/acpi/arm64/gtdt.c
+++ b/drivers/acpi/arm64/gtdt.c
@@ -13,6 +13,7 @@
 
 #include <linux/acpi.h>
 #include <linux/init.h>
+#include <linux/irqdomain.h>
 #include <linux/kernel.h>
 
 #include <clocksource/arm_arch_timer.h>
@@ -37,6 +38,28 @@ struct acpi_gtdt_descriptor {
 
 static struct acpi_gtdt_descriptor 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; _g;	\
+	     _g = next_platform_timer(_g))
+
+static inline bool is_timer_block(void *platform_timer)
+{
+	struct acpi_gtdt_header *gh = platform_timer;
+
+	return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK;
+}
+
 static int __init map_gt_gsi(u32 interrupt, u32 flags)
 {
 	int trigger, polarity;
@@ -155,3 +178,137 @@ int __init acpi_gtdt_init(struct acpi_table_header *table,
 
 	return 0;
 }
+
+static int __init gtdt_parse_timer_block(struct acpi_gtdt_timer_block *block,
+					 struct arch_timer_mem *timer_mem)
+{
+	int i;
+	struct arch_timer_mem_frame *frame;
+	struct acpi_gtdt_timer_entry *gtdt_frame;
+
+	if (!block->timer_count) {
+		pr_err(FW_BUG "GT block present, but frame count is zero.");
+		return -ENODEV;
+	}
+
+	if (block->timer_count > ARCH_TIMER_MEM_MAX_FRAMES) {
+		pr_err(FW_BUG "GT block lists %d frames, ACPI spec only allows 8\n",
+		       block->timer_count);
+		return -EINVAL;
+	}
+
+	timer_mem->cntctlbase = (phys_addr_t)block->block_address;
+	/*
+	 * The CNTCTLBase frame is 4KB (register offsets 0x000 - 0xFFC).
+	 * See ARM DDI 0487A.k_iss10775, page I1-5129, Table I1-3
+	 * "CNTCTLBase memory map".
+	 */
+	timer_mem->size = SZ_4K;
+
+	gtdt_frame = (void *)block + block->timer_offset;
+	if (gtdt_frame + block->timer_count != (void *)block + block->header.length)
+		return -EINVAL;
+
+	/*
+	 * Get the GT timer Frame data for every GT Block Timer
+	 */
+	for (i = 0; i < block->timer_count; i++, gtdt_frame++) {
+		if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER)
+			continue;
+		if (gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES ||
+		    !gtdt_frame->base_address || !gtdt_frame->timer_interrupt)
+			goto error;
+
+		frame = &timer_mem->frame[gtdt_frame->frame_number];
+
+		/* duplicate frame */
+		if (frame->valid)
+			goto error;
+
+		frame->phys_irq = map_gt_gsi(gtdt_frame->timer_interrupt,
+					     gtdt_frame->timer_flags);
+		if (frame->phys_irq <= 0) {
+			pr_warn("failed to map physical timer irq in frame %d.\n",
+				gtdt_frame->frame_number);
+			goto error;
+		}
+
+		if (gtdt_frame->virtual_timer_interrupt) {
+			frame->virt_irq =
+				map_gt_gsi(gtdt_frame->virtual_timer_interrupt,
+					   gtdt_frame->virtual_timer_flags);
+			if (frame->virt_irq <= 0) {
+				pr_warn("failed to map virtual timer irq in frame %d.\n",
+					gtdt_frame->frame_number);
+				goto error;
+			}
+		} else {
+			pr_debug("virtual timer in frame %d not implemented.\n",
+				 gtdt_frame->frame_number);
+		}
+
+		frame->cntbase = gtdt_frame->base_address;
+		/*
+		 * The CNTBaseN frame is 4KB (register offsets 0x000 - 0xFFC).
+		 * See ARM DDI 0487A.k_iss10775, page I1-5130, Table I1-4
+		 * "CNTBaseN memory map".
+		 */
+		frame->size = SZ_4K;
+		frame->valid = true;
+	}
+
+	return 0;
+
+error:
+	do {
+		if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER ||
+		    gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES)
+			continue;
+
+		frame = &timer_mem->frame[gtdt_frame->frame_number];
+
+		if (frame->phys_irq > 0)
+			acpi_unregister_gsi(gtdt_frame->timer_interrupt);
+		frame->phys_irq = 0;
+
+		if (frame->virt_irq > 0)
+			acpi_unregister_gsi(gtdt_frame->virtual_timer_interrupt);
+		frame->virt_irq = 0;
+	} while (i-- >= 0 && gtdt_frame--);
+
+	return -EINVAL;
+}
+
+/**
+ * acpi_arch_timer_mem_init() - Get the info of all GT blocks in GTDT table.
+ * @timer_mem:	The pointer to the array of struct arch_timer_mem for returning
+ *		the result of parsing. The element number of this array should
+ *		be platform_timer_count(the total number of platform timers).
+ * @timer_count: It points to a integer variable which is used for storing the
+ *		number of GT blocks we have parsed.
+ *
+ * Return: 0 if success, -EINVAL/-ENODEV if error.
+ */
+int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem,
+				    int *timer_count)
+{
+	int ret;
+	void *platform_timer;
+
+	*timer_count = 0;
+	for_each_platform_timer(platform_timer) {
+		if (is_timer_block(platform_timer)) {
+			ret = gtdt_parse_timer_block(platform_timer, timer_mem);
+			if (ret)
+				return ret;
+			timer_mem++;
+			(*timer_count)++;
+		}
+	}
+
+	if (*timer_count)
+		pr_info("found %d memory-mapped timer block(s).\n",
+			*timer_count);
+
+	return 0;
+}
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 4b5c146..3193724 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -599,6 +599,7 @@ enum acpi_reconfig_event  {
 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);
+int acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, int *timer_count);
 #endif
 
 #else	/* !CONFIG_ACPI */
-- 
1.9.1

[PATCH 15/16] clocksource: arm_arch_timer: add GTDT support for memory-mapped timer

[Mark Rutland]

From: Fu Wei <fu.wei@linaro.org>

The patch add memory-mapped timer register support by using the
information provided by the new GTDT driver of ACPI.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
[Mark: verify CNTFRQ, only register the first frame]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 79 ++++++++++++++++++++++++++++++++++--
 1 file changed, 76 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index e398228..2208fa4 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1386,10 +1386,79 @@ static int __init arch_timer_mem_of_init(struct device_node *np)
 		       arch_timer_mem_of_init);
 
 #ifdef CONFIG_ACPI_GTDT
-/* Initialize per-processor generic timer */
+static int __init
+arch_timer_mem_verify_cntfrq(struct arch_timer_mem *timer_mem)
+{
+	struct arch_timer_mem_frame *frame;
+	u32 rate;
+	int i;
+
+	for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) {
+		frame = &timer_mem->frame[i];
+
+		if (!frame->valid)
+			continue;
+
+		rate = arch_timer_mem_frame_get_cntfrq(frame);
+		if (rate == arch_timer_rate)
+			continue;
+
+		pr_err(FW_BUG "CNTFRQ mismatch: frame @ %pa: (0x%08lx), CPU: (0x%08lx)\n",
+			&frame->cntbase,
+			(unsigned long)rate, (unsigned long)arch_timer_rate);
+
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int __init arch_timer_mem_acpi_init(int platform_timer_count)
+{
+	struct arch_timer_mem *timers, *timer;
+	struct arch_timer_mem_frame *frame;
+	int timer_count, i, ret = 0;
+
+	timers = kcalloc(platform_timer_count, sizeof(*timers),
+			    GFP_KERNEL);
+	if (!timers)
+		return -ENOMEM;
+
+	ret = acpi_arch_timer_mem_init(timers, &timer_count);
+	if (ret || !timer_count)
+		goto out;
+
+	for (i = 0; i < timer_count; i++) {
+		ret = arch_timer_mem_verify_cntfrq(&timers[i]);
+		if (ret) {
+			pr_err("Disabling MMIO timers due to CNTFRQ mismatch\n");
+			goto out;
+		}
+	}
+
+	/*
+	 * While unlikely, it's theoretically possible that none of the frames
+	 * in a timer expose the combination of feature we want.
+	 */
+	for (i = i; i < timer_count; i++) {
+		timer = &timers[i];
+
+		frame = arch_timer_mem_find_best_frame(timer);
+		if (frame)
+			break;
+	}
+
+	if (frame)
+		ret = arch_timer_mem_frame_register(frame);
+out:
+	kfree(timers);
+	return ret;
+}
+
+/* Initialize per-processor generic timer and memory-mapped timer(if present) */
 static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 {
-	int ret;
+	int ret, platform_timer_count;
 
 	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
 		pr_warn("already initialized, skipping\n");
@@ -1398,7 +1467,7 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 
 	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
 
-	ret = acpi_gtdt_init(table, NULL);
+	ret = acpi_gtdt_init(table, &platform_timer_count);
 	if (ret) {
 		pr_err("Failed to init GTDT table.\n");
 		return ret;
@@ -1441,6 +1510,10 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 	if (ret)
 		return ret;
 
+	if (platform_timer_count &&
+	    arch_timer_mem_acpi_init(platform_timer_count))
+		pr_err("Failed to initialize memory-mapped timer.\n");
+
 	return arch_timer_common_init();
 }
 CLOCKSOURCE_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
-- 
1.9.1

[PATCH 16/16] acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver

[Mark Rutland]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset=y, Size: 4430 bytes --]

From: Fu Wei <fu.wei@linaro.org>

This driver adds support for parsing SBSA Generic Watchdog timer
in GTDT, parse all info in SBSA Generic Watchdog Structure in GTDT,
and creating a platform device with that information.

This allows the operating system to obtain device data from the
resource of platform device. The platform device named "sbsa-gwdt"
can be used by the ARM SBSA Generic Watchdog driver.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/acpi/arm64/gtdt.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 103 insertions(+)

diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c
index b904667..597a737 100644
--- a/drivers/acpi/arm64/gtdt.c
+++ b/drivers/acpi/arm64/gtdt.c
@@ -15,6 +15,7 @@
 #include <linux/init.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
+#include <linux/platform_device.h>
 
 #include <clocksource/arm_arch_timer.h>
 
@@ -60,6 +61,17 @@ static inline bool is_timer_block(void *platform_timer)
 	return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK;
 }
 
+static inline bool is_non_secure_watchdog(void *platform_timer)
+{
+	struct acpi_gtdt_header *gh = platform_timer;
+	struct acpi_gtdt_watchdog *wd = platform_timer;
+
+	if (gh->type != ACPI_GTDT_TYPE_WATCHDOG)
+		return false;
+
+	return !(wd->timer_flags & ACPI_GTDT_WATCHDOG_SECURE);
+}
+
 static int __init map_gt_gsi(u32 interrupt, u32 flags)
 {
 	int trigger, polarity;
@@ -312,3 +324,94 @@ int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem,
 
 	return 0;
 }
+
+/*
+ * Initialize a SBSA generic Watchdog platform device info from GTDT
+ */
+static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd,
+					int index)
+{
+	struct platform_device *pdev;
+	int irq = map_gt_gsi(wd->timer_interrupt, wd->timer_flags);
+
+	/*
+	 * According to SBSA specification the size of refresh and control
+	 * frames of SBSA Generic Watchdog is SZ_4K(Offset 0x000 – 0xFFF).
+	 */
+	struct resource res[] = {
+		DEFINE_RES_MEM(wd->control_frame_address, SZ_4K),
+		DEFINE_RES_MEM(wd->refresh_frame_address, SZ_4K),
+		DEFINE_RES_IRQ(irq),
+	};
+	int nr_res = ARRAY_SIZE(res);
+
+	pr_debug("found a Watchdog (0x%llx/0x%llx gsi:%u flags:0x%x).\n",
+		 wd->refresh_frame_address, wd->control_frame_address,
+		 wd->timer_interrupt, wd->timer_flags);
+
+	if (!(wd->refresh_frame_address && wd->control_frame_address)) {
+		pr_err(FW_BUG "failed to get the Watchdog base address.\n");
+		acpi_unregister_gsi(wd->timer_interrupt);
+		return -EINVAL;
+	}
+
+	if (irq <= 0) {
+		pr_warn("failed to map the Watchdog interrupt.\n");
+		nr_res--;
+	}
+
+	/*
+	 * Add a platform device named "sbsa-gwdt" to match the platform driver.
+	 * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog
+	 * The platform driver can get device info below by matching this name.
+	 */
+	pdev = platform_device_register_simple("sbsa-gwdt", index, res, nr_res);
+	if (IS_ERR(pdev)) {
+		acpi_unregister_gsi(wd->timer_interrupt);
+		return PTR_ERR(pdev);
+	}
+
+	return 0;
+}
+
+static int __init gtdt_sbsa_gwdt_init(void)
+{
+	void *platform_timer;
+	struct acpi_table_header *table;
+	int ret, timer_count, gwdt_count = 0;
+
+	if (acpi_disabled)
+		return 0;
+
+	if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table)))
+		return -EINVAL;
+
+	/*
+	 * Note: Even though the global variable acpi_gtdt_desc has been
+	 * initialized by acpi_gtdt_init() while initializing the arch timers,
+	 * when we call this function to get SBSA watchdogs info from GTDT, the
+	 * pointers stashed in it are stale (since they are early temporary
+	 * mappings carried out before acpi_permanent_mmap is set) and we need
+	 * to re-initialize them with permanent mapped pointer values to let the
+	 * GTDT parsing possible.
+	 */
+	ret = acpi_gtdt_init(table, &timer_count);
+	if (ret || !timer_count)
+		return ret;
+
+	for_each_platform_timer(platform_timer) {
+		if (is_non_secure_watchdog(platform_timer)) {
+			ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count);
+			if (ret)
+				break;
+			gwdt_count++;
+		}
+	}
+
+	if (gwdt_count)
+		pr_info("found %d SBSA generic Watchdog(s).\n", gwdt_count);
+
+	return ret;
+}
+
+device_initcall(gtdt_sbsa_gwdt_init);
-- 
1.9.1

Re: [GIT PULL 00/16] clocksource: arm_arch_timer: GTDT-based MMIO timer support

[Daniel Lezcano]

On Wed, Apr 19, 2017 at 05:44:17PM +0100, Mark Rutland wrote:
> Hi Daniel,
> 
> The series enables support for the MMIO architected timers (useful for
> system-level idle), which need to be probed via the GTDT when using ACPI. 
> 
> I realise this is a little late, but I would very much appreciate if you could
> pull these arch timer GTDT patches for v4.12. The series has been largely fine
> for a while now, and the major hold-ups were edge cases in error handling which
> have now been addressed.
> 
> The bulk of the series is a refactoring to cleanly separate the core driver, DT
> probe path, and ACPI probe path. The final patch of the series adds GTDT-based
> probing of the SBSA watchdog, using the new GTDT probing infrastructure. I've
> tested the patches on arm and arm64 platforms.
> 
> The ACPI parts have all been appropriately acked, and it's preferred that these
> all go through the clocksource tree.
> 
> The series is based on Marc's arch-timer-errata tag, which is alread in
> tip/timers/core.

Hi Thomas,

the series is ok for me. Is it possible to pull these changes directly in 
tip/timers/core?

There is a single trivial conflict with a trace.

  -- Daniel

> 
> The following changes since commit d003d029cea8a28139b4f9b88a36b8fac864f45b:
> 
>   arm64: arch_timer: Add HISILICON_ERRATUM_161010101 ACPI matching data (2017-04-07 11:22:10 +0100)
> 
> are available in the git repository at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git tags/arch-timer-gtdt
> 
> for you to fetch changes up to ca9ae5ec4ef0ed13833b03297ab319676965492c:
> 
>   acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver (2017-04-19 17:00:15 +0100)
> 
> ----------------------------------------------------------------
> arch timer GTDT patches
> 
> - arch_timer cleanups and refactoring
> - new common GTDT parser
> - GTDT-based MMIO arch_timer support
> - GTDT-based SBSA watchdog support
> 
> ----------------------------------------------------------------
> Fu Wei (16):
>       clocksource: arm_arch_timer: clean up printk usage
>       clocksource: arm_arch_timer: rename type macros
>       clocksource: arm_arch_timer: rename the PPI enum
>       clocksource: arm_arch_timer: move enums and defines to header file
>       clocksource: arm_arch_timer: add a new enum for spi type
>       clocksource: arm_arch_timer: rework PPI selection
>       clocksource: arm_arch_timer: split dt-only rate handling
>       clocksource: arm_arch_timer: refactor arch_timer_needs_probing
>       clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init call
>       clocksource: arm_arch_timer: add structs to describe MMIO timer
>       clocksource: arm_arch_timer: split MMIO timer probing.
>       acpi/arm64: Add GTDT table parse driver
>       clocksource: arm_arch_timer: simplify ACPI support code.
>       acpi/arm64: Add memory-mapped timer support in GTDT driver
>       clocksource: arm_arch_timer: add GTDT support for memory-mapped timer
>       acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver
> 
>  arch/arm64/Kconfig                   |   1 +
>  drivers/acpi/arm64/Kconfig           |   3 +
>  drivers/acpi/arm64/Makefile          |   1 +
>  drivers/acpi/arm64/gtdt.c            | 417 +++++++++++++++++++++++++
>  drivers/clocksource/arm_arch_timer.c | 573 +++++++++++++++++++++++------------
>  include/clocksource/arm_arch_timer.h |  34 +++
>  include/linux/acpi.h                 |   7 +
>  7 files changed, 834 insertions(+), 202 deletions(-)
>  create mode 100644 drivers/acpi/arm64/gtdt.c

-- 

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Re: [GIT PULL 00/16] clocksource: arm_arch_timer: GTDT-based MMIO timer support

[Mark Rutland]

On Wed, Apr 19, 2017 at 11:39:44PM +0200, Daniel Lezcano wrote:
> On Wed, Apr 19, 2017 at 05:44:17PM +0100, Mark Rutland wrote:
> > Hi Daniel,

> > I realise this is a little late, but I would very much appreciate if you could
> > pull these arch timer GTDT patches for v4.12. The series has been largely fine
> > for a while now, and the major hold-ups were edge cases in error handling which
> > have now been addressed.

> Hi Thomas,
> 
> the series is ok for me. Is it possible to pull these changes directly in 
> tip/timers/core?

The tip-bot tells me it was.

Many thanks for picking these up, it's much appreciated.

Mark.

Re: [GIT PULL 00/16] clocksource: arm_arch_timer: GTDT-based MMIO timer support

[Fu Wei]

Hi Daniel, Lorenzo, Mark,


On 20 April 2017 at 16:26, Mark Rutland <mark.rutland@arm.com> wrote:
> On Wed, Apr 19, 2017 at 11:39:44PM +0200, Daniel Lezcano wrote:
>> On Wed, Apr 19, 2017 at 05:44:17PM +0100, Mark Rutland wrote:
>> > Hi Daniel,
>
>> > I realise this is a little late, but I would very much appreciate if you could
>> > pull these arch timer GTDT patches for v4.12. The series has been largely fine
>> > for a while now, and the major hold-ups were edge cases in error handling which
>> > have now been addressed.
>
>> Hi Thomas,
>>
>> the series is ok for me. Is it possible to pull these changes directly in
>> tip/timers/core?
>
> The tip-bot tells me it was.
>
> Many thanks for picking these up, it's much appreciated.

Great thanks to all of you, I very appreciate all the help and
suggestion from you :-)

>
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat