[PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[fu.wei]

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

This patchset:
    (1)Preparation for adding GTDT support in arm_arch_timer:
        1. Move some enums and marcos to header file;
        2. Add a new enum for spi type;
        3. Improve printk relevant code;
        4. Rename some enums and defines;
        5. Rework PPI determination;
        6. Rework counter frequency detection;
        7. Refactor arch_timer_needs_probing, move it into DT init call
        8. Introduce some new structs and refactor the MMIO timer init code
        for reusing some common code.

    (2)Introduce ACPI GTDT parser: drivers/acpi/arm64/acpi_gtdt.c
    Parse all kinds of timer in GTDT table of ACPI:arch timer,
    memory-mapped timer and SBSA Generic Watchdog timer.
    This driver can help to simplify all the relevant timer drivers,
    and separate all the ACPI GTDT knowledge from them.

    (3)Simplify ACPI code for arm_arch_timer

    (4)Add GTDT support for ARM memory-mapped timer.

This patchset has been tested on the following platforms with ACPI enabled:
    (1)ARM Foundation v8 model

Changelog:
v19: https://lkml.org/lkml/2016/12/21/
     Fix a '\n' missing in a error message in arch_timer_mem_init.
     Add "request_mem_region" for ioremapping cntbase, according to
     f947ee1 clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map()
     Rebase to 4.9.0-gfb779ff

v18: https://lkml.org/lkml/2016/12/8/446
     Fix 8/15 patch problem of "int ret;" in arch_timer_acpi_init.
     Rebase to 4.9.0-rc8-g9269898

v17: https://lkml.org/lkml/2016/11/25/140
     Take out some cleanups from 4/15.
     Merge 5/15 and 6/15, improve PPI determination code,
     improve commit message.
     Rework counter frequency detection.
     Move arch_timer_needs_of_probing into DT init call.
     Move Platform Timer scan loop back to timer init call to avoid allocating
     and free memory.
     Improve all the exported functions' comment.

v16: https://lkml.org/lkml/2016/11/16/268
     Fix patchset problem about static enum ppi_nr of 01/13 in v15.
     Refactor arch_timer_detect_rate.
     Refactor arch_timer_needs_probing.

v15: https://lkml.org/lkml/2016/11/15/366
     Re-order patches
     Add arm_arch_timer refactoring patches to prepare for GTDT:
         1. rename some  enums and defines, and some cleanups
         2. separate out arch_timer_uses_ppi init code and fix a potential bug
         3. Improve some new structs, refactor the timer init code.
     Since the some structs have been changed, GTDT parser for memory-mapped
     timer and SBSA Generic Watchdog timer have been update.

v14: https://lkml.org/lkml/2016/9/28/573
     Separate memory-mapped timer GTDT support into two patches
         1. Refactor the timer init code to prepare for GTDT
         2. Add GTDT support for memory-mapped timer

v13: http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1231717.html
     Improve arm_arch_timer code for memory-mapped
     timer GTDT support, refactor original memory-mapped timer
     dt support for reusing some common code.

v12: https://lkml.org/lkml/2016/9/13/250
     Rebase to latest Linux 4.8-rc6
     Delete the confusing "skipping" in the error message.

V11: https://lkml.org/lkml/2016/9/6/354
     Rebase to latest Linux 4.8-rc5
     Delete typedef (suggested by checkpatch.pl)

V10: https://lkml.org/lkml/2016/7/26/215
     Drop the "readq" patch.
     Rebase to latest Linux 4.7.

V9: https://lkml.org/lkml/2016/7/25/345
    Improve pr_err message in acpi gtdt driver.
    Update Commit message for 7/9
    shorten the irq mapping function name
    Improve GTDT driver for memory-mapped timer

v8: https://lkml.org/lkml/2016/7/19/660
    Improve "pr_fmt(fmt)" definition: add "ACPI" in front of "GTDT",
    and also improve printk message.
    Simplify is_timer_block and is_watchdog.
    Merge acpi_gtdt_desc_init and gtdt_arch_timer_init into acpi_gtdt_init();
    Delete __init in include/linux/acpi.h for GTDT API
    Make ARM64 select GTDT.
    Delete "#include <linux/module.h>" from acpi_gtdt.c
    Simplify GT block parse code.

v7: https://lkml.org/lkml/2016/7/13/769
    Move the GTDT driver to drivers/acpi/arm64
    Add add the ARM64-specific ACPI Support maintainers in MAINTAINERS
    Merge 3 patches of GTDT parser driver.
    Fix the for_each_platform_timer bug.

v6: https://lkml.org/lkml/2016/6/29/580
    split the GTDT driver to 4 parts: basic, arch_timer, memory-mapped timer,
    and SBSA Generic Watchdog timer
    Improve driver by suggestions and example code from Daniel Lezcano

v5: https://lkml.org/lkml/2016/5/24/356
    Sorting out all patches, simplify the API of GTDT driver:
    GTDT driver just fills the data struct for arm_arch_timer driver.

v4: https://lists.linaro.org/pipermail/linaro-acpi/2016-March/006667.html
    Delete the kvm relevant patches
    Separate two patches for sorting out the code for arm_arch_timer.
    Improve irq info export code to allow missing irq info in GTDT table.

v3: https://lkml.org/lkml/2016/2/1/658
    Improve GTDT driver code:
      (1)improve pr_* by defining pr_fmt(fmt)
      (2)simplify gtdt_sbsa_gwdt_init
      (3)improve gtdt_arch_timer_data_init, if table is NULL, it will try
      to get GTDT table.
    Move enum ppi_nr to arm_arch_timer.h, and add enum spi_nr.
    Add arm_arch_timer get ppi from DT and GTDT support for kvm.

v2: https://lkml.org/lkml/2015/12/2/10
    Rebase to latest kernel version(4.4-rc3).
    Fix the bug about the config problem,
    use CONFIG_ACPI_GTDT instead of CONFIG_ACPI in arm_arch_timer.c

v1: The first upstreaming version: https://lkml.org/lkml/2015/10/28/553

Fu Wei (15):
  clocksource/drivers/arm_arch_timer: Move enums and defines to header
    file
  clocksource/drivers/arm_arch_timer: Add a new enum for spi type
  clocksource/drivers/arm_arch_timer: Improve printk relevant code
  clocksource/drivers/arm_arch_timer: rename some enums and defines.
  clocksource/drivers/arm_arch_timer: rework PPI determination
  clocksource/drivers/arm_arch_timer: Rework counter frequency
    detection.
  clocksource/drivers/arm_arch_timer: Refactor arch_timer_needs_probing
  clocksource/drivers/arm_arch_timer: move arch_timer_needs_of_probing
    into DT init call
  clocksource/drivers/arm_arch_timer: Introduce some new structs to
    prepare for GTDT
  clocksource/drivers/arm_arch_timer: Refactor the timer init code to
    prepare for GTDT
  acpi/arm64: Add GTDT table parse driver
  clocksource/drivers/arm_arch_timer: Simplify ACPI support code.
  acpi/arm64: Add memory-mapped timer support in GTDT driver
  clocksource/drivers/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            | 374 +++++++++++++++++++++++++++
 drivers/clocksource/arm_arch_timer.c | 483 ++++++++++++++++++++---------------
 drivers/watchdog/Kconfig             |   1 +
 include/clocksource/arm_arch_timer.h |  45 +++-
 include/linux/acpi.h                 |   7 +
 virt/kvm/arm/hyp/timer-sr.c          |   6 +-
 9 files changed, 712 insertions(+), 209 deletions(-)
 create mode 100644 drivers/acpi/arm64/gtdt.c

-- 
2.9.3

[PATCH v19 01/15] clocksource/drivers/arm_arch_timer: Move enums and defines to header file

[fu.wei]

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.

Split out the relevant defines and enums into arm_arch_timer.h, and
change "enum ppi_nr" to "enum arch_timer_ppi_nr" to avoid the potential
name clashes.
Also switch "enum ppi_nr" to "enum arch_timer_ppi_nr" in
arm_arch_timer.c.
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>
---
 drivers/clocksource/arm_arch_timer.c | 13 +------------
 include/clocksource/arm_arch_timer.h | 12 ++++++++++++
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 02fef68..6c8cb01 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -51,8 +51,6 @@
 #define CNTV_TVAL	0x38
 #define CNTV_CTL	0x3c
 
-#define ARCH_CP15_TIMER	BIT(0)
-#define ARCH_MEM_TIMER	BIT(1)
 static unsigned arch_timers_present __initdata;
 
 static void __iomem *arch_counter_base;
@@ -65,20 +63,11 @@ struct arch_timer {
 #define to_arch_timer(e) container_of(e, struct arch_timer, evt)
 
 static u32 arch_timer_rate;
-
-enum ppi_nr {
-	PHYS_SECURE_PPI,
-	PHYS_NONSECURE_PPI,
-	VIRT_PPI,
-	HYP_PPI,
-	MAX_TIMER_PPI
-};
-
 static int arch_timer_ppi[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 = VIRT_PPI;
 static bool arch_timer_c3stop;
 static bool arch_timer_mem_use_virtual;
 static bool arch_counter_suspend_stop;
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index caedb74..557f869 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_CP15_TIMER			BIT(0)
+#define ARCH_MEM_TIMER			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 {
+	PHYS_SECURE_PPI,
+	PHYS_NONSECURE_PPI,
+	VIRT_PPI,
+	HYP_PPI,
+	MAX_TIMER_PPI
+};
+
 #define ARCH_TIMER_PHYS_ACCESS		0
 #define ARCH_TIMER_VIRT_ACCESS		1
 #define ARCH_TIMER_MEM_PHYS_ACCESS	2
-- 
2.9.3

[PATCH v19 02/15] clocksource/drivers/arm_arch_timer: Add a new enum for spi type

[fu.wei]

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>
---
 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 6c8cb01..9aba1c0 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -968,9 +968,9 @@ 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 557f869..d23c381 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -46,6 +46,12 @@ enum arch_timer_ppi_nr {
 	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
-- 
2.9.3

[PATCH v19 03/15] clocksource/drivers/arm_arch_timer: Improve printk relevant code

[fu.wei]

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

This patch defines pr_fmt(fmt) for all pr_* functions,
then the pr_* doesn't need to add "arch_timer:" everytime.

According to the suggestion from checkpatch.pl:
(1) delete some Blank Spaces in arch_timer_banner;
(2) delete a redundant Tab in a bland line of arch_timer_init(void)

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>
---
 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 9aba1c0..7203f95 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -32,6 +32,9 @@
 
 #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))
 
@@ -505,22 +508,22 @@ arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
 
 	/* 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" :
 			"");
 }
@@ -621,8 +624,7 @@ 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())
@@ -715,8 +717,7 @@ 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;
 	}
 
@@ -769,7 +770,7 @@ 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);
 	}
 
@@ -847,7 +848,7 @@ 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;
 		}
 	}
@@ -861,7 +862,7 @@ static int __init arch_timer_init(void)
 		return ret;
 
 	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[VIRT_PPI];
-	
+
 	return 0;
 }
 
@@ -870,7 +871,7 @@ 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;
 	}
 
@@ -918,7 +919,7 @@ 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;
 	}
 
@@ -933,7 +934,7 @@ 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;
 		}
@@ -963,7 +964,7 @@ 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;
 	}
 
@@ -974,7 +975,7 @@ 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;
 	}
@@ -1016,7 +1017,7 @@ 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;
 	}
 
-- 
2.9.3

[PATCH v19 04/15] clocksource/drivers/arm_arch_timer: rename some enums and defines.

[fu.wei]

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

Rename some enums and defines, to unify the format of enums and defines
in arm_arch_timer.h, also update all the users of these enums and defines:
    drivers/clocksource/arm_arch_timer.c
    virt/kvm/arm/hyp/timer-sr.c

No functional change.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
---
 drivers/clocksource/arm_arch_timer.c | 111 ++++++++++++++++++-----------------
 include/clocksource/arm_arch_timer.h |  24 ++++----
 virt/kvm/arm/hyp/timer-sr.c          |   6 +-
 3 files changed, 73 insertions(+), 68 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 7203f95..c7b4e50 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -66,11 +66,11 @@ struct arch_timer {
 #define to_arch_timer(e) container_of(e, struct arch_timer, evt)
 
 static u32 arch_timer_rate;
-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 arch_timer_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;
@@ -341,7 +341,7 @@ static void fsl_a008585_set_sne(struct clock_event_device *clk)
 	if (!static_branch_unlikely(&arch_timer_read_ool_enabled))
 		return;
 
-	if (arch_timer_uses_ppi == VIRT_PPI)
+	if (arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI)
 		clk->set_next_event = fsl_a008585_set_next_event_virt;
 	else
 		clk->set_next_event = fsl_a008585_set_next_event_phys;
@@ -353,7 +353,7 @@ 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";
@@ -361,14 +361,14 @@ 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;
@@ -448,8 +448,8 @@ 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)
@@ -470,14 +470,15 @@ 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);
 
 	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();
@@ -514,16 +515,17 @@ arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
 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 ?
-			(arch_timer_uses_ppi == VIRT_PPI) ? "virt" : "phys" :
+		type & ARCH_TIMER_TYPE_CP15 ?
+			(arch_timer_uses_ppi == ARCH_TIMER_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" :
 			"");
 }
@@ -589,8 +591,9 @@ 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 (IS_ENABLED(CONFIG_ARM64) || arch_timer_uses_ppi == VIRT_PPI)
+	if (type & ARCH_TIMER_TYPE_CP15) {
+		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;
@@ -628,7 +631,7 @@ 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);
 }
@@ -691,24 +694,24 @@ 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;
@@ -740,7 +743,7 @@ 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:
@@ -761,7 +764,7 @@ 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;
@@ -804,13 +807,15 @@ arch_timer_needs_probing(int type, const struct of_device_id *matches)
 
 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;
 	}
 
@@ -835,16 +840,16 @@ 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) {
@@ -861,7 +866,7 @@ 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;
 }
@@ -870,13 +875,13 @@ 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;
-	for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
+	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
+	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);
@@ -898,7 +903,7 @@ 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,
@@ -916,7 +921,7 @@ 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");
@@ -1016,28 +1021,28 @@ 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] =
+	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);
 
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index d23c381..48376a5 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -20,18 +20,18 @@
 #include <linux/timecounter.h>
 #include <linux/types.h>
 
-#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)
 
 #define ARCH_TIMER_CTRL_ENABLE		(1 << 0)
 #define ARCH_TIMER_CTRL_IT_MASK		(1 << 1)
 #define ARCH_TIMER_CTRL_IT_STAT		(1 << 2)
 
-#define CNTHCTL_EL1PCTEN		(1 << 0)
-#define CNTHCTL_EL1PCEN			(1 << 1)
-#define CNTHCTL_EVNTEN			(1 << 2)
-#define CNTHCTL_EVNTDIR			(1 << 3)
-#define CNTHCTL_EVNTI			(0xF << 4)
+#define ARCH_TIMER_CNTHCTL_EL1PCTEN	(1 << 0)
+#define ARCH_TIMER_CNTHCTL_EL1PCEN	(1 << 1)
+#define ARCH_TIMER_CNTHCTL_EVNTEN	(1 << 2)
+#define ARCH_TIMER_CNTHCTL_EVNTDIR	(1 << 3)
+#define ARCH_TIMER_CNTHCTL_EVNTI	(0xF << 4)
 
 enum arch_timer_reg {
 	ARCH_TIMER_REG_CTRL,
@@ -39,11 +39,11 @@ enum arch_timer_reg {
 };
 
 enum arch_timer_ppi_nr {
-	PHYS_SECURE_PPI,
-	PHYS_NONSECURE_PPI,
-	VIRT_PPI,
-	HYP_PPI,
-	MAX_TIMER_PPI
+	ARCH_TIMER_PHYS_SECURE_PPI,
+	ARCH_TIMER_PHYS_NONSECURE_PPI,
+	ARCH_TIMER_VIRT_PPI,
+	ARCH_TIMER_HYP_PPI,
+	ARCH_TIMER_MAX_TIMER_PPI
 };
 
 enum arch_timer_spi_nr {
diff --git a/virt/kvm/arm/hyp/timer-sr.c b/virt/kvm/arm/hyp/timer-sr.c
index 798866a..695b9d9 100644
--- a/virt/kvm/arm/hyp/timer-sr.c
+++ b/virt/kvm/arm/hyp/timer-sr.c
@@ -37,7 +37,7 @@ void __hyp_text __timer_save_state(struct kvm_vcpu *vcpu)
 
 	/* Allow physical timer/counter access for the host */
 	val = read_sysreg(cnthctl_el2);
-	val |= CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN;
+	val |= ARCH_TIMER_CNTHCTL_EL1PCTEN | ARCH_TIMER_CNTHCTL_EL1PCEN;
 	write_sysreg(val, cnthctl_el2);
 
 	/* Clear cntvoff for the host */
@@ -55,8 +55,8 @@ void __hyp_text __timer_restore_state(struct kvm_vcpu *vcpu)
 	 * Physical counter access is allowed
 	 */
 	val = read_sysreg(cnthctl_el2);
-	val &= ~CNTHCTL_EL1PCEN;
-	val |= CNTHCTL_EL1PCTEN;
+	val &= ~ARCH_TIMER_CNTHCTL_EL1PCEN;
+	val |= ARCH_TIMER_CNTHCTL_EL1PCTEN;
 	write_sysreg(val, cnthctl_el2);
 
 	if (timer->enabled) {
-- 
2.9.3

[PATCH v19 05/15] clocksource/drivers/arm_arch_timer: rework PPI determination

[fu.wei]

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* potentialy also use the
non-secure PPI. This is somewhat confusing.

For arm64, where it never makes sense to use the secure PPI, this
means we must always request the useless secure PPI, adding to the
confusion. For ACPI, where we may not even have a valid secure PPI
number, this is additionally problematic. We need the driver to be
able to use *only* the non-secure PPI.

The logic to choose which PPI to use is intertwined with other logic
in arch_timer_init(). This patch factors the PPI determination out
into a new function named arch_timer_select_ppi, and then reworks it
so that we can handle having only a non-secure PPI.

This patch also moves arch_timer_ppi verification out to caller,
because we can verify the configuration from device-tree for ARM by this
way.

Meanwhile, because we will select ARCH_TIMER_PHYS_NONSECURE_PPI for ARM64,
the logic in arch_timer_register also need to be updated.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.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 c7b4e50..c7b4482 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -702,7 +702,7 @@ 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);
@@ -824,39 +824,41 @@ 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_hyp_mode_available() && 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 (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)
@@ -904,6 +906,13 @@ 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,
@@ -1049,6 +1058,12 @@ 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);
 
-- 
2.9.3

Re: [PATCH v19 05/15] clocksource/drivers/arm_arch_timer: rework PPI determination

[Mark Rutland]

On Wed, Dec 21, 2016 at 02:45:53PM +0800, fu.wei@linaro.org wrote:
[...]

> -	if (is_hyp_mode_available() || !arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) {
> -		bool has_ppi;
> +	if (is_hyp_mode_available() && 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 (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;

For a 32-bit platform booted at hyp (with a virt PPI available), the new
logic will select ARCH_TIMER_VIRT_PPI. I beleive that will break KVM.

I think the logic should be:

	if (is_kernel_in_hyp_mode())
		return ARCH_TIMER_HYP_PPI;

	if (!is_hyp_mode_available() &&
	    arch_timer_ppi[ARCH_TIMER_VIRT_PPI])
	    	return ARCH_TIMER_VIRT_PPI;
	
	if (IS_ENABLED(CONFIG_ARM64))
		return ARCH_TIMER_PHYS_NONSECURE_PPI;
	
	return ARCH_TIMER_PHYS_SECURE_PPI;

Please use that instead (keeping the comment you retained).

> +static int __init arch_timer_init(void)
> +{
> +	int ret;
>  
>  	ret = arch_timer_register();
>  	if (ret)
> @@ -904,6 +906,13 @@ 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,
> @@ -1049,6 +1058,12 @@ 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;
> +	}

I see that we have to duplicate this so we can special-case the
DT-specific behaviour, so that's fine by me.

If you can fix the arch_timer_select_ppi() logic as above, this should
be fine.

Thanks,
Mark.

Re: [PATCH v19 05/15] clocksource/drivers/arm_arch_timer: rework PPI determination

[Fu Wei]

Hi Mark,

On 17 January 2017 at 01:29, Mark Rutland <mark.rutland@arm.com> wrote:
> On Wed, Dec 21, 2016 at 02:45:53PM +0800, fu.wei@linaro.org wrote:
> [...]
>
>> -     if (is_hyp_mode_available() || !arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) {
>> -             bool has_ppi;
>> +     if (is_hyp_mode_available() && 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 (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;
>
> For a 32-bit platform booted at hyp (with a virt PPI available), the new
> logic will select ARCH_TIMER_VIRT_PPI. I beleive that will break KVM.
>
> I think the logic should be:
>
>         if (is_kernel_in_hyp_mode())
>                 return ARCH_TIMER_HYP_PPI;
>
>         if (!is_hyp_mode_available() &&
>             arch_timer_ppi[ARCH_TIMER_VIRT_PPI])
>                 return ARCH_TIMER_VIRT_PPI;
>
>         if (IS_ENABLED(CONFIG_ARM64))
>                 return ARCH_TIMER_PHYS_NONSECURE_PPI;
>
>         return ARCH_TIMER_PHYS_SECURE_PPI;
>
> Please use that instead (keeping the comment you retained).

Great thanks for pointing it out, that is bug.
also got this bug report from Huawei engineer.

I have fixed it using your example code, thanks!


>
>> +static int __init arch_timer_init(void)
>> +{
>> +     int ret;
>>
>>       ret = arch_timer_register();
>>       if (ret)
>> @@ -904,6 +906,13 @@ 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,
>> @@ -1049,6 +1058,12 @@ 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;
>> +     }
>
> I see that we have to duplicate this so we can special-case the
> DT-specific behaviour, so that's fine by me.

Yes, that is the reason of the duplication :-)

>
> If you can fix the arch_timer_select_ppi() logic as above, this should
> be fine.

Done, thanks :-)

>
> Thanks,
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

[PATCH v19 06/15] clocksource/drivers/arm_arch_timer: Rework counter frequency detection.

[fu.wei]

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

Currently, the counter frequency detection call(arch_timer_detect_rate)
combines all the ways to get counter frequency: device-tree property,
system coprocessor register, MMIO timer. But in the most of use cases,
we don't need all the ways to try:
For example, reading device-tree property will be needed only when
system boot with device-tree, getting frequency from MMIO timer register
will beneeded only when we init MMIO timer.

This patch separates paths to determine frequency:
Separate out device-tree code, keep them in device-tree init function.
Separate out the MMIO frequency and the sysreg frequency detection call,
and use the appropriate one for the counter.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
---
 drivers/clocksource/arm_arch_timer.c | 49 +++++++++++++++++++++++-------------
 1 file changed, 31 insertions(+), 18 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index c7b4482..9a1f138 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -488,27 +488,31 @@ static int arch_timer_starting_cpu(unsigned int cpu)
 	return 0;
 }
 
-static void
-arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
+static void arch_timer_detect_rate(void)
 {
-	/* Who has more than one independent system counter? */
-	if (arch_timer_rate)
-		return;
+	/*
+	 * Try to get the timer frequency from
+	 * cntfrq_el0(system coprocessor register).
+	 */
+	if (!arch_timer_rate)
+		arch_timer_rate = arch_timer_get_cntfrq();
+
+	/* Check the timer frequency. */
+	if (!arch_timer_rate)
+		pr_warn("frequency not available\n");
+}
 
+static void arch_timer_mem_detect_rate(void __iomem *cntbase)
+{
 	/*
-	 * Try to determine the frequency from the device tree or CNTFRQ,
-	 * if ACPI is enabled, get the frequency from CNTFRQ ONLY.
+	 * Try to determine the frequency from
+	 * CNTFRQ in memory-mapped timer.
 	 */
-	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 (!arch_timer_rate)
+		arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
 
 	/* Check the timer frequency. */
-	if (arch_timer_rate == 0)
+	if (!arch_timer_rate)
 		pr_warn("frequency not available\n");
 }
 
@@ -886,7 +890,9 @@ 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);
+	if (!arch_timer_rate &&
+	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
+		arch_timer_detect_rate();
 
 	arch_timer_c3stop = !of_property_read_bool(np, "always-on");
 
@@ -994,7 +1000,14 @@ static int __init arch_timer_mem_init(struct device_node *np)
 		goto out;
 	}
 
-	arch_timer_detect_rate(base, np);
+	/*
+	 * Try to determine the frequency from the device tree,
+	 * if fail, get the frequency from CNTFRQ.
+	 */
+	if (!arch_timer_rate &&
+	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
+		arch_timer_mem_detect_rate(base);
+
 	ret = arch_timer_mem_register(base, irq);
 	if (ret)
 		goto out;
@@ -1056,7 +1069,7 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 		gtdt->non_secure_el2_flags);
 
 	/* Get the frequency from CNTFRQ */
-	arch_timer_detect_rate(NULL, NULL);
+	arch_timer_detect_rate();
 
 	arch_timer_uses_ppi = arch_timer_select_ppi();
 	if (!arch_timer_ppi[arch_timer_uses_ppi]) {
-- 
2.9.3

Re: [PATCH v19 06/15] clocksource/drivers/arm_arch_timer: Rework counter frequency detection.

[Mark Rutland]

On Wed, Dec 21, 2016 at 02:45:54PM +0800, fu.wei@linaro.org wrote:
> From: Fu Wei <fu.wei@linaro.org>
> 
> Currently, the counter frequency detection call(arch_timer_detect_rate)
> combines all the ways to get counter frequency: device-tree property,
> system coprocessor register, MMIO timer. But in the most of use cases,
> we don't need all the ways to try:
> For example, reading device-tree property will be needed only when
> system boot with device-tree, getting frequency from MMIO timer register
> will beneeded only when we init MMIO timer.
> 
> This patch separates paths to determine frequency:
> Separate out device-tree code, keep them in device-tree init function.

Splitting these out makes sense to me.

> Separate out the MMIO frequency and the sysreg frequency detection call,
> and use the appropriate one for the counter.

> Signed-off-by: Fu Wei <fu.wei@linaro.org>
> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
> ---
>  drivers/clocksource/arm_arch_timer.c | 49 +++++++++++++++++++++++-------------
>  1 file changed, 31 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
> index c7b4482..9a1f138 100644
> --- a/drivers/clocksource/arm_arch_timer.c
> +++ b/drivers/clocksource/arm_arch_timer.c
> @@ -488,27 +488,31 @@ static int arch_timer_starting_cpu(unsigned int cpu)
>  	return 0;
>  }
>  
> -static void
> -arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
> +static void arch_timer_detect_rate(void)
>  {
> -	/* Who has more than one independent system counter? */
> -	if (arch_timer_rate)
> -		return;
> +	/*
> +	 * Try to get the timer frequency from
> +	 * cntfrq_el0(system coprocessor register).
> +	 */
> +	if (!arch_timer_rate)
> +		arch_timer_rate = arch_timer_get_cntfrq();
> +
> +	/* Check the timer frequency. */
> +	if (!arch_timer_rate)
> +		pr_warn("frequency not available\n");
> +}
>  
> +static void arch_timer_mem_detect_rate(void __iomem *cntbase)
> +{
>  	/*
> -	 * Try to determine the frequency from the device tree or CNTFRQ,
> -	 * if ACPI is enabled, get the frequency from CNTFRQ ONLY.
> +	 * Try to determine the frequency from
> +	 * CNTFRQ in memory-mapped timer.
>  	 */
> -	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 (!arch_timer_rate)
> +		arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
>  
>  	/* Check the timer frequency. */
> -	if (arch_timer_rate == 0)
> +	if (!arch_timer_rate)
>  		pr_warn("frequency not available\n");
>  }

There's a subtle change in behaviour here. Previously for ACPI we'd only
ever use the sysreg CNTFRQ value for arch_timer_rate, whereas now we
might use the MMIO timer rate. Maybe that's not a big deal, but I will
need to think.

Generally, the logic to determine the rate is fairly gnarly regardless.

It would be nice if we could split the MMIO and sysreg rates entirely,
and kill the implicit relationship between the two, or at least make one
canonical and warn if the two differ.

Thanks,
Mark.

Re: [PATCH v19 06/15] clocksource/drivers/arm_arch_timer: Rework counter frequency detection.

[Fu Wei]

Hi Mark,

On 17 January 2017 at 01:50, Mark Rutland <mark.rutland@arm.com> wrote:
> On Wed, Dec 21, 2016 at 02:45:54PM +0800, fu.wei@linaro.org wrote:
>> From: Fu Wei <fu.wei@linaro.org>
>>
>> Currently, the counter frequency detection call(arch_timer_detect_rate)
>> combines all the ways to get counter frequency: device-tree property,
>> system coprocessor register, MMIO timer. But in the most of use cases,
>> we don't need all the ways to try:
>> For example, reading device-tree property will be needed only when
>> system boot with device-tree, getting frequency from MMIO timer register
>> will beneeded only when we init MMIO timer.
>>
>> This patch separates paths to determine frequency:
>> Separate out device-tree code, keep them in device-tree init function.
>
> Splitting these out makes sense to me.

OK , will do

>
>> Separate out the MMIO frequency and the sysreg frequency detection call,
>> and use the appropriate one for the counter.
>
>> Signed-off-by: Fu Wei <fu.wei@linaro.org>
>> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
>> ---
>>  drivers/clocksource/arm_arch_timer.c | 49 +++++++++++++++++++++++-------------
>>  1 file changed, 31 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
>> index c7b4482..9a1f138 100644
>> --- a/drivers/clocksource/arm_arch_timer.c
>> +++ b/drivers/clocksource/arm_arch_timer.c
>> @@ -488,27 +488,31 @@ static int arch_timer_starting_cpu(unsigned int cpu)
>>       return 0;
>>  }
>>
>> -static void
>> -arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
>> +static void arch_timer_detect_rate(void)
>>  {
>> -     /* Who has more than one independent system counter? */
>> -     if (arch_timer_rate)
>> -             return;
>> +     /*
>> +      * Try to get the timer frequency from
>> +      * cntfrq_el0(system coprocessor register).
>> +      */
>> +     if (!arch_timer_rate)
>> +             arch_timer_rate = arch_timer_get_cntfrq();
>> +
>> +     /* Check the timer frequency. */
>> +     if (!arch_timer_rate)
>> +             pr_warn("frequency not available\n");
>> +}
>>
>> +static void arch_timer_mem_detect_rate(void __iomem *cntbase)
>> +{
>>       /*
>> -      * Try to determine the frequency from the device tree or CNTFRQ,
>> -      * if ACPI is enabled, get the frequency from CNTFRQ ONLY.
>> +      * Try to determine the frequency from
>> +      * CNTFRQ in memory-mapped timer.
>>        */
>> -     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 (!arch_timer_rate)
>> +             arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
>>
>>       /* Check the timer frequency. */
>> -     if (arch_timer_rate == 0)
>> +     if (!arch_timer_rate)

I think you mean this one, this is for keeping consistency with
arch_timer_detect_rate.

>>               pr_warn("frequency not available\n");
>>  }
>
> There's a subtle change in behaviour here. Previously for ACPI we'd only
> ever use the sysreg CNTFRQ value for arch_timer_rate, whereas now we
> might use the MMIO timer rate. Maybe that's not a big deal, but I will
> need to think.
>
> Generally, the logic to determine the rate is fairly gnarly regardless.
>
> It would be nice if we could split the MMIO and sysreg rates entirely,

Yes, I am doing this way,

For sysreg rates,
static void arch_timer_detect_rate(void)
{
/*
* Try to get the timer frequency from
* cntfrq_el0(system coprocessor register).
*/
if (!arch_timer_rate)
arch_timer_rate = arch_timer_get_cntfrq();

/* Check the timer frequency. */
if (!arch_timer_rate)
pr_warn("frequency not available\n");
}

For MMIO timer,
static void arch_timer_mem_detect_rate(void __iomem *cntbase)
{
/*
* Try to determine the frequency from
* CNTFRQ in memory-mapped timer.
*/
if (!arch_timer_rate)
arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);

/* Check the timer frequency. */
if (!arch_timer_rate)
pr_warn("frequency not available\n");
}

in arch_time_*_init, only call  arch_timer_detect_rate,
in arch_timer_mem_init, only call arch_timer_mem_detect_rate.

But you are right, this is fairly gnarly regardless.

> and kill the implicit relationship between the two, or at least make one
> canonical and warn if the two differ.

So I think maybe we can do this:

static void __arch_timer_determine_rate(u32 rate)
{
/* Check the timer frequency. */
if (!arch_timer_rate)
if (rate)
arch_timer_rate = rate;
else
pr_warn("frequency not available\n");
else if (arch_timer_rate != rate)
pr_warn("got different frequency, keep original.\n");
}

static void arch_timer_detect_rate(void)
{
/*
* Try to get the timer frequency from
* cntfrq_el0(system coprocessor register).
*/
__arch_timer_determine_rate(arch_timer_get_cntfrq());
}

static void arch_timer_mem_detect_rate(void __iomem *cntbase)
{
/*
* Try to get the timer frequency from
* CNTFRQ in the MMIO timer.
*/
__arch_timer_determine_rate(readl_relaxed(cntbase + CNTFRQ));
}

any thought?

>
> Thanks,
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

[PATCH v19 07/15] clocksource/drivers/arm_arch_timer: Refactor arch_timer_needs_probing

[fu.wei]

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

When system init with device-tree, we don't know which node will be
initialized first. And the code in arch_timer_common_init should wait
until per-cpu timer and MMIO timer are both initialized. So we need
arch_timer_needs_probing to detect the init status of system.

But currently the code is dispersed in arch_timer_needs_probing and
arch_timer_common_init. And the function name doesn't specify that
it's only for device-tree. This is somewhat confusing.

This patch move all related code from arch_timer_common_init to
arch_timer_needs_probing, refactor it, and rename it to
arch_timer_needs_of_probing. And make sure that it will be called
only if acpi is disabled.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
---
 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 9a1f138..5f7be04 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -795,15 +795,28 @@ static const struct of_device_id arch_timer_mem_of_match[] __initconst = {
 	{},
 };
 
-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;
@@ -811,17 +824,8 @@ arch_timer_needs_probing(int type, const struct of_device_id *matches)
 
 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);
-- 
2.9.3

[PATCH v19 08/15] clocksource/drivers/arm_arch_timer: move arch_timer_needs_of_probing into DT init call

[fu.wei]

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

Because arch_timer_needs_of_probing is only for booting with device-tree,
but arch_timer_common_init is a generic init call which shouldn't include
the FW-specific code. It's better to put arch_timer_needs_of_probing into
DT init function.

But for per-cpu timer, the arch_timer_common_init is called from
arch_timer_init. For reaching the goal above, this patch disassemble
arch_timer_init and use arch_timer_register and arch_timer_common_init
directly, just like arch_timer_mem init code is doing.
By this way, all the DT relevant code are only called from DT init call.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
---
 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 5f7be04..9113df8 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -824,9 +824,6 @@ 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();
@@ -864,26 +861,9 @@ 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;
 
 	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
 		pr_warn("multiple nodes in dt, skipping\n");
@@ -894,6 +874,8 @@ 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];
+
 	if (!arch_timer_rate &&
 	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
 		arch_timer_detect_rate();
@@ -928,7 +910,14 @@ 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);
@@ -1016,7 +1005,8 @@ 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);
@@ -1045,6 +1035,7 @@ 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) {
@@ -1072,6 +1063,8 @@ 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];
+
 	/* Get the frequency from CNTFRQ */
 	arch_timer_detect_rate();
 
@@ -1084,8 +1077,11 @@ 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_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
-- 
2.9.3

[PATCH v19 09/15] clocksource/drivers/arm_arch_timer: Introduce some new structs to prepare for GTDT

[fu.wei]

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

The patch introduce two new structs: arch_timer_mem, arch_timer_mem_frame.
And also introduce a new define: ARCH_TIMER_MEM_MAX_FRAMES

These will be used for refactoring the memory-mapped timer init code to
prepare for GTDT

Signed-off-by: Fu Wei <fu.wei@linaro.org>
---
 include/clocksource/arm_arch_timer.h | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index 48376a5..3403247 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 +74,21 @@ struct arch_timer_kvm_info {
 	int virtual_irq;
 };
 
+struct arch_timer_mem_frame {
+	int frame_nr;
+	phys_addr_t cntbase;
+	size_t size;
+	int phys_irq;
+	int virt_irq;
+};
+
+struct arch_timer_mem {
+	phys_addr_t cntctlbase;
+	size_t size;
+	int num_frames;
+	struct arch_timer_mem_frame frame[ARCH_TIMER_MEM_MAX_FRAMES];
+};
+
 #ifdef CONFIG_ARM_ARCH_TIMER
 
 extern u32 arch_timer_get_rate(void);
-- 
2.9.3

[PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

[fu.wei]

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

The patch refactor original memory-mapped timer init code:
    (1) Refactor "arch_timer_mem_init", make it become a common code for
        memory-mapped timer init.
    (2) Add a new function "arch_timer_mem_of_init" for DT init.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
---
 drivers/clocksource/arm_arch_timer.c | 135 ++++++++++++++++++++++++-----------
 1 file changed, 92 insertions(+), 43 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 9113df8..b10cc26 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -922,17 +922,17 @@ 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 int __init arch_timer_mem_init(struct arch_timer_mem *timer_mem)
 {
-	struct device_node *frame, *best_frame = NULL;
 	void __iomem *cntctlbase, *base;
-	unsigned int irq, ret = -EINVAL;
+	struct arch_timer_mem_frame *best_frame = NULL;
+	unsigned int irq;
 	u32 cnttidr;
+	int i, ret;
 
-	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
-	cntctlbase = of_iomap(np, 0);
+	cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size);
 	if (!cntctlbase) {
-		pr_err("Can't find CNTCTLBase\n");
+		pr_err("Can't map CNTCTLBase.\n");
 		return -ENXIO;
 	}
 
@@ -942,26 +942,18 @@ 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;
-
-		if (of_property_read_u32(frame, "frame-number", &n)) {
-			pr_err("Missing frame-number\n");
-			of_node_put(frame);
-			goto out;
-		}
+	for (i = 0; i < timer_mem->num_frames; i++) {
+		u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
+			     CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
+		int n = timer_mem->frame[i].frame_nr;
 
 		/* 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));
 
 		if ((cnttidr & CNTTIDR_VIRT(n)) &&
 		    !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) {
-			of_node_put(best_frame);
-			best_frame = frame;
+			best_frame = &timer_mem->frame[i];
 			arch_timer_mem_use_virtual = true;
 			break;
 		}
@@ -969,51 +961,108 @@ 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 = &timer_mem->frame[i];
 	}
+	iounmap(cntctlbase);
 
-	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;
+	if (!best_frame) {
+		pr_err("Can't find frame for register\n");
+		return -EINVAL;
 	}
 
 	if (arch_timer_mem_use_virtual)
-		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_VIRT_SPI);
+		irq = best_frame->virt_irq;
 	else
-		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_PHYS_SPI);
+		irq = best_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;
 	}
 
-	/*
-	 * Try to determine the frequency from the device tree,
-	 * if fail, get the frequency from CNTFRQ.
-	 */
-	if (!arch_timer_rate &&
-	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
-		arch_timer_mem_detect_rate(base);
+	if (!request_mem_region(best_frame->cntbase, best_frame->size,
+				"arch_mem_timer"))
+		return -EBUSY;
+
+	base = ioremap(best_frame->cntbase, best_frame->size);
+	if (!base) {
+		pr_err("Can't map frame's registers\n");
+		return -ENXIO;
+	}
+
+	arch_timer_mem_detect_rate(base);
 
 	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 device_node *frame_node;
+	struct resource res;
+	int i, ret = -EINVAL;
+
+	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);
+
+	i = 0;
+	for_each_available_child_of_node(np, frame_node) {
+		int n;
+		struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
+
+		if (of_property_read_u32(frame_node, "frame-number", &n)) {
+			pr_err("Missing frame-number\n");
+			of_node_put(frame_node);
+			goto out;
+		}
+		frame->frame_nr = n;
+
+		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);
 
-	if (!arch_timer_needs_of_probing())
+		if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
+			break;
+	}
+	timer_mem->num_frames = i;
+
+	/* Try to determine the frequency from the device tree */
+	if (!arch_timer_rate)
+		of_property_read_u32(np, "clock-frequency", &arch_timer_rate);
+
+	ret = arch_timer_mem_init(timer_mem);
+	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)
-- 
2.9.3

Re: [PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

[Mark Rutland]

On Wed, Dec 21, 2016 at 02:45:58PM +0800, fu.wei@linaro.org wrote:
> From: Fu Wei <fu.wei@linaro.org>
> 
> The patch refactor original memory-mapped timer init code:
>     (1) Refactor "arch_timer_mem_init", make it become a common code for
>         memory-mapped timer init.
>     (2) Add a new function "arch_timer_mem_of_init" for DT init.

As a general note, please write proper commit messages, describing what
the problem is, and why we are making the changes. These bullet points
don't add anything to what can be derived from a glance at the code.

For this patch, you can use:

  clocksource: arm_arch_timer: refactor MMIO timer probing

  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 factors all the DT-specific logic out of
  arch_timer_mem_init(), into a new function, arch_timer_mem_of_init().
  The former pokes the hardware and determines the suitablility of
  frames based on a datastructure populated by the latter.

  This cleanly separates the two and will make it possible to add
  probing using the ACPI GTDT in subsequent patches.

[...]

> +	for_each_available_child_of_node(np, frame_node) {
> +		int n;
> +		struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
> +
> +		if (of_property_read_u32(frame_node, "frame-number", &n)) {
> +			pr_err("Missing frame-number\n");
> +			of_node_put(frame_node);
> +			goto out;
> +		}
> +		frame->frame_nr = n;
> +
> +		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);
>  
> -	if (!arch_timer_needs_of_probing())
> +		if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
> +			break;
> +	}

It would be good if we could warn upon seeing more than
ARCH_TIMER_MEM_MAX_FRAMES children, since that's obviously an error.

Thanks,
Mark.

Re: [PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

[Fu Wei]

Hi Mark,

On 17 January 2017 at 02:30, Mark Rutland <mark.rutland@arm.com> wrote:
> On Wed, Dec 21, 2016 at 02:45:58PM +0800, fu.wei@linaro.org wrote:
>> From: Fu Wei <fu.wei@linaro.org>
>>
>> The patch refactor original memory-mapped timer init code:
>>     (1) Refactor "arch_timer_mem_init", make it become a common code for
>>         memory-mapped timer init.
>>     (2) Add a new function "arch_timer_mem_of_init" for DT init.
>
> As a general note, please write proper commit messages, describing what
> the problem is, and why we are making the changes. These bullet points
> don't add anything to what can be derived from a glance at the code.
>
> For this patch, you can use:
>
>   clocksource: arm_arch_timer: refactor MMIO timer probing
>
>   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 factors all the DT-specific logic out of
>   arch_timer_mem_init(), into a new function, arch_timer_mem_of_init().
>   The former pokes the hardware and determines the suitablility of
>   frames based on a datastructure populated by the latter.
>
>   This cleanly separates the two and will make it possible to add
>   probing using the ACPI GTDT in subsequent patches.

Great thanks for this upstream tip.
I have used your example commit message instead.
It will be in v20.

>
> [...]
>
>> +     for_each_available_child_of_node(np, frame_node) {
>> +             int n;
>> +             struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
>> +
>> +             if (of_property_read_u32(frame_node, "frame-number", &n)) {
>> +                     pr_err("Missing frame-number\n");
>> +                     of_node_put(frame_node);
>> +                     goto out;
>> +             }
>> +             frame->frame_nr = n;
>> +
>> +             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);
>>
>> -     if (!arch_timer_needs_of_probing())
>> +             if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
>> +                     break;
>> +     }
>
> It would be good if we could warn upon seeing more than
> ARCH_TIMER_MEM_MAX_FRAMES children, since that's obviously an error.

OK, NP, will use

if (i >= ARCH_TIMER_MEM_MAX_FRAMES) {
        pr_err(FW_BUG "too many frames, ARMv8 spec only allows 8.\n");
        goto out;
}

at the beginning of this loop.

Here will be replaced by  i++;

Great thanks for your suggestion!

>
> Thanks,
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

Re: [PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

[Fu Wei]

Hi Mark,

On 17 January 2017 at 18:30, Fu Wei <fu.wei@linaro.org> wrote:
> Hi Mark,
>
> On 17 January 2017 at 02:30, Mark Rutland <mark.rutland@arm.com> wrote:
>> On Wed, Dec 21, 2016 at 02:45:58PM +0800, fu.wei@linaro.org wrote:
>>> From: Fu Wei <fu.wei@linaro.org>
>>>
>>> The patch refactor original memory-mapped timer init code:
>>>     (1) Refactor "arch_timer_mem_init", make it become a common code for
>>>         memory-mapped timer init.
>>>     (2) Add a new function "arch_timer_mem_of_init" for DT init.
>>
>> As a general note, please write proper commit messages, describing what
>> the problem is, and why we are making the changes. These bullet points
>> don't add anything to what can be derived from a glance at the code.
>>
>> For this patch, you can use:
>>
>>   clocksource: arm_arch_timer: refactor MMIO timer probing
>>
>>   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 factors all the DT-specific logic out of
>>   arch_timer_mem_init(), into a new function, arch_timer_mem_of_init().
>>   The former pokes the hardware and determines the suitablility of
>>   frames based on a datastructure populated by the latter.
>>
>>   This cleanly separates the two and will make it possible to add
>>   probing using the ACPI GTDT in subsequent patches.
>
> Great thanks for this upstream tip.
> I have used your example commit message instead.
> It will be in v20.
>
>>
>> [...]
>>
>>> +     for_each_available_child_of_node(np, frame_node) {
>>> +             int n;
>>> +             struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
>>> +
>>> +             if (of_property_read_u32(frame_node, "frame-number", &n)) {
>>> +                     pr_err("Missing frame-number\n");
>>> +                     of_node_put(frame_node);
>>> +                     goto out;
>>> +             }
>>> +             frame->frame_nr = n;
>>> +
>>> +             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);
>>>
>>> -     if (!arch_timer_needs_of_probing())
>>> +             if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
>>> +                     break;
>>> +     }
>>
>> It would be good if we could warn upon seeing more than
>> ARCH_TIMER_MEM_MAX_FRAMES children, since that's obviously an error.
>
> OK, NP, will use
>
> if (i >= ARCH_TIMER_MEM_MAX_FRAMES) {
>         pr_err(FW_BUG "too many frames, ARMv8 spec only allows 8.\n");

Sorry,  this should be "ARM spec only allows 8.\n"

Not only ARMv8, but also ARMv7


>         goto out;
> }
>
> at the beginning of this loop.
>
> Here will be replaced by  i++;
>
> Great thanks for your suggestion!
>
>>
>> Thanks,
>> Mark.
>
>
>
> --
> Best regards,
>
> Fu Wei
> Software Engineer
> Red Hat



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

Re: [PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

[Timur Tabi]

Fu Wei wrote:
> if (i >= ARCH_TIMER_MEM_MAX_FRAMES) {
>         pr_err(FW_BUG "too many frames, ARMv8 spec only allows 8.\n");

pr_err(FW_BUG "too many frames, ARMv8 spec only allows %u.\n",
	ARCH_TIMER_MEM_MAX_FRAMES);

-- 
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the
Code Aurora Forum, hosted by The Linux Foundation.

Re: [PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

[Mark Rutland]

On Tue, Jan 17, 2017 at 06:18:12AM -0600, Timur Tabi wrote:
> Fu Wei wrote:
> >if (i >= ARCH_TIMER_MEM_MAX_FRAMES) {
> >        pr_err(FW_BUG "too many frames, ARMv8 spec only allows 8.\n");
> 
> pr_err(FW_BUG "too many frames, ARMv8 spec only allows %u.\n",
> 	ARCH_TIMER_MEM_MAX_FRAMES);

While I don't see ARCH_TIMER_MEM_MAX_FRAMES changing, this would be
nicer to ensure the result obviously matches.

As for wording, I'd perfer:

	pr_err(FW_BUG "too many frames, only %u are permitted.\n",
	       ARCH_TIMER_MEM_MAX_FRAMES);

... so as to avoid any confusion between spec versions and so on. We can
reconsider the message if/when that changes.

Thanks,
Mark.

Re: [PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

[Fu Wei]

Hi Mark,

On 17 January 2017 at 20:29, Mark Rutland <mark.rutland@arm.com> wrote:
> On Tue, Jan 17, 2017 at 06:18:12AM -0600, Timur Tabi wrote:
>> Fu Wei wrote:
>> >if (i >= ARCH_TIMER_MEM_MAX_FRAMES) {
>> >        pr_err(FW_BUG "too many frames, ARMv8 spec only allows 8.\n");
>>
>> pr_err(FW_BUG "too many frames, ARMv8 spec only allows %u.\n",
>>       ARCH_TIMER_MEM_MAX_FRAMES);
>
> While I don't see ARCH_TIMER_MEM_MAX_FRAMES changing, this would be
> nicer to ensure the result obviously matches.
>
> As for wording, I'd perfer:
>
>         pr_err(FW_BUG "too many frames, only %u are permitted.\n",
>                ARCH_TIMER_MEM_MAX_FRAMES);

OK, will do so.
Thanks!

>
> ... so as to avoid any confusion between spec versions and so on. We can
> reconsider the message if/when that changes.
>
> Thanks,
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

[PATCH v19 11/15] acpi/arm64: Add GTDT table parse driver

[fu.wei]

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>
---
 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 1117421..ab1ee10 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..d93a790
--- /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.
+ * 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.
+ */
+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
+ *				number of platform timers. It can be NULL, if
+ *				driver don'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)
+{
+	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_debug("Revision:%d doesn't support Platform Timers.\n",
+			 table->revision);
+	else if (!gtdt->platform_timer_count)
+		pr_debug("No Platform Timer.\n");
+	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;
+		}
+	}
+
+	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 5b36974..d0b271e 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -597,6 +597,12 @@ 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

[PATCH v19 12/15] clocksource/drivers/arm_arch_timer: Simplify ACPI support code.

[fu.wei]

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>
---
 drivers/clocksource/arm_arch_timer.c | 46 ++++++++++--------------------------
 1 file changed, 13 insertions(+), 33 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index b10cc26..5a0dd54 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1064,59 +1064,36 @@ 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];
 
-	/* Get the frequency from CNTFRQ */
-	arch_timer_detect_rate();
-
 	arch_timer_uses_ppi = arch_timer_select_ppi();
 	if (!arch_timer_ppi[arch_timer_uses_ppi]) {
 		pr_err("No interrupt available, giving up\n");
@@ -1124,7 +1101,10 @@ 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);
+
+	/* Get the frequency from CNTFRQ */
+	arch_timer_detect_rate();
 
 	ret = arch_timer_register();
 	if (ret)
-- 
2.9.3

[PATCH v19 13/15] acpi/arm64: Add memory-mapped timer support in GTDT driver

[fu.wei]

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>
---
 drivers/acpi/arm64/gtdt.c | 124 ++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/acpi.h      |   1 +
 2 files changed, 125 insertions(+)

diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c
index d93a790..91ea6cb 100644
--- a/drivers/acpi/arm64/gtdt.c
+++ b/drivers/acpi/arm64/gtdt.c
@@ -37,6 +37,28 @@ 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 +177,105 @@ int __init acpi_gtdt_init(struct acpi_table_header *table,
 
 	return ret;
 }
+
+static int __init gtdt_parse_timer_block(struct acpi_gtdt_timer_block *block,
+					 struct arch_timer_mem *data)
+{
+	int i;
+	struct acpi_gtdt_timer_entry *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;
+	}
+
+	data->cntctlbase = (phys_addr_t)block->block_address;
+	/*
+	 * According to "Table * CNTCTLBase memory map" of
+	 * <ARM Architecture Reference Manual> for ARMv8,
+	 * The size of the CNTCTLBase frame is 4KB(Offset 0x000 – 0xFFC).
+	 */
+	data->size = SZ_4K;
+	data->num_frames = block->timer_count;
+
+	frame = (void *)block + block->timer_offset;
+	if (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++, frame++) {
+		if (!frame->base_address || !frame->timer_interrupt)
+			return -EINVAL;
+
+		data->frame[i].phys_irq = map_gt_gsi(frame->timer_interrupt,
+						     frame->timer_flags);
+		if (data->frame[i].phys_irq <= 0) {
+			pr_warn("failed to map physical timer irq in frame %d.\n",
+				i);
+			return -EINVAL;
+		}
+
+		data->frame[i].virt_irq =
+			map_gt_gsi(frame->virtual_timer_interrupt,
+				   frame->virtual_timer_flags);
+		if (data->frame[i].virt_irq <= 0) {
+			pr_warn("failed to map virtual timer irq in frame %d.\n",
+				i);
+			acpi_unregister_gsi(frame->timer_interrupt);
+			return -EINVAL;
+		}
+
+		data->frame[i].frame_nr = frame->frame_number;
+		data->frame[i].cntbase = frame->base_address;
+		/*
+		 * According to "Table * CNTBaseN memory map" of
+		 * <ARM Architecture Reference Manual> for ARMv8,
+		 * The size of the CNTBaseN frame is 4KB(Offset 0x000 – 0xFFC).
+		 */
+		data->frame[i].size = SZ_4K;
+	}
+
+	return 0;
+}
+
+/**
+ * acpi_arch_timer_mem_init() - Get the info of all GT blocks in GTDT table.
+ * @data:	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).
+ * @count:	The pointer of int variate for returning 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 *data,
+				    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, data);
+			if (ret)
+				return ret;
+			data++;
+			(*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 d0b271e..51e85b9 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -601,6 +601,7 @@ int acpi_reconfig_notifier_unregister(struct notifier_block *nb);
 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 *data, int *timer_count);
 #endif
 
 #else	/* !CONFIG_ACPI */
-- 
2.9.3

[PATCH v19 14/15] clocksource/drivers/arm_arch_timer: Add GTDT support for memory-mapped timer

[fu.wei]

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>
---
 drivers/clocksource/arm_arch_timer.c | 35 ++++++++++++++++++++++++++++++++---
 1 file changed, 32 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 5a0dd54..5d08d3d 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1065,10 +1065,36 @@ CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
 		       arch_timer_mem_of_init);
 
 #ifdef CONFIG_ACPI_GTDT
-/* Initialize per-processor generic timer */
+static int __init arch_timer_mem_acpi_init(int platform_timer_count)
+{
+	struct arch_timer_mem *timer_mem;
+	int timer_count, i, ret;
+
+	timer_mem = kcalloc(platform_timer_count, sizeof(*timer_mem),
+			    GFP_KERNEL);
+	if (!timer_mem)
+		return -ENOMEM;
+
+	ret = acpi_arch_timer_mem_init(timer_mem, &timer_count);
+	if (ret || !timer_count)
+		goto error;
+
+	for (i = 0; i < timer_count; i++) {
+		ret = arch_timer_mem_init(timer_mem);
+		if (!ret)
+			break;
+		timer_mem++;
+	}
+
+error:
+	kfree(timer_mem);
+	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");
@@ -1077,7 +1103,7 @@ 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;
@@ -1110,6 +1136,9 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 	if (ret)
 		return ret;
 
+	if (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);
-- 
2.9.3

[PATCH v19 15/15] acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver

[fu.wei]

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>
---
 drivers/acpi/arm64/gtdt.c | 93 +++++++++++++++++++++++++++++++++++++++++++++++
 drivers/watchdog/Kconfig  |  1 +
 2 files changed, 94 insertions(+)

diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c
index 91ea6cb..22d3659 100644
--- a/drivers/acpi/arm64/gtdt.c
+++ b/drivers/acpi/arm64/gtdt.c
@@ -14,6 +14,7 @@
 #include <linux/acpi.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/platform_device.h>
 
 #include <clocksource/arm_arch_timer.h>
 
@@ -59,6 +60,13 @@ static inline bool is_timer_block(void *platform_timer)
 	return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK;
 }
 
+static inline bool is_watchdog(void *platform_timer)
+{
+	struct acpi_gtdt_header *gh = platform_timer;
+
+	return gh->type == ACPI_GTDT_TYPE_WATCHDOG;
+}
+
 static int __init map_gt_gsi(u32 interrupt, u32 flags)
 {
 	int trigger, polarity;
@@ -279,3 +287,88 @@ int __init acpi_arch_timer_mem_init(struct arch_timer_mem *data,
 
 	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);
+	int no_irq = 1;
+
+	/*
+	 * 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),
+	};
+
+	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");
+		return -EINVAL;
+	}
+
+	if (!wd->timer_interrupt)
+		pr_warn(FW_BUG "failed to get the Watchdog interrupt.\n");
+	else if (irq <= 0)
+		pr_warn("failed to map the Watchdog interrupt.\n");
+	else
+		no_irq = 0;
+
+	/*
+	 * Add a platform device named "sbsa-gwdt" to match the platform driver.
+	 * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog
+	 * The platform driver (like drivers/watchdog/sbsa_gwdt.c)can get device
+	 * info below by matching this name.
+	 */
+	pdev = platform_device_register_simple("sbsa-gwdt", index, res,
+					       ARRAY_SIZE(res) - no_irq);
+	if (IS_ERR(pdev)) {
+		acpi_unregister_gsi(wd->timer_interrupt);
+		return PTR_ERR(pdev);
+	}
+
+	return 0;
+}
+
+static int __init gtdt_sbsa_gwdt_init(void)
+{
+	int ret, i = 0;
+	void *platform_timer;
+	struct acpi_table_header *table;
+
+	if (acpi_disabled)
+		return 0;
+
+	if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table)))
+		return -EINVAL;
+
+	ret = acpi_gtdt_init(table, NULL);
+	if (ret)
+		return ret;
+
+	for_each_platform_timer(platform_timer) {
+		if (is_watchdog(platform_timer)) {
+			ret = gtdt_import_sbsa_gwdt(platform_timer, i);
+			if (ret)
+				break;
+			i++;
+		}
+	}
+
+	if (i)
+		pr_info("found %d SBSA generic Watchdog(s).\n", i);
+
+	return ret;
+}
+
+device_initcall(gtdt_sbsa_gwdt_init);
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 3eb58cb..a95c62d 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -219,6 +219,7 @@ config ARM_SBSA_WATCHDOG
 	tristate "ARM SBSA Generic Watchdog"
 	depends on ARM64
 	depends on ARM_ARCH_TIMER
+	depends on ACPI_GTDT || !ACPI
 	select WATCHDOG_CORE
 	help
 	  ARM SBSA Generic Watchdog has two stage timeouts:
-- 
2.9.3

Re: [PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[Fu Wei]

Hi Mark,

This v19 (I have mentioned it in my previous email) is the latest
patchset which can be applied on v4.10-rc4 directly.

please review this patchset, thanks! :-)

On 21 December 2016 at 14:45,  <fu.wei@linaro.org> wrote:
> From: Fu Wei <fu.wei@linaro.org>
>
> This patchset:
>     (1)Preparation for adding GTDT support in arm_arch_timer:
>         1. Move some enums and marcos to header file;
>         2. Add a new enum for spi type;
>         3. Improve printk relevant code;
>         4. Rename some enums and defines;
>         5. Rework PPI determination;
>         6. Rework counter frequency detection;
>         7. Refactor arch_timer_needs_probing, move it into DT init call
>         8. Introduce some new structs and refactor the MMIO timer init code
>         for reusing some common code.
>
>     (2)Introduce ACPI GTDT parser: drivers/acpi/arm64/acpi_gtdt.c
>     Parse all kinds of timer in GTDT table of ACPI:arch timer,
>     memory-mapped timer and SBSA Generic Watchdog timer.
>     This driver can help to simplify all the relevant timer drivers,
>     and separate all the ACPI GTDT knowledge from them.
>
>     (3)Simplify ACPI code for arm_arch_timer
>
>     (4)Add GTDT support for ARM memory-mapped timer.
>
> This patchset has been tested on the following platforms with ACPI enabled:
>     (1)ARM Foundation v8 model
>
> Changelog:
> v19: https://lkml.org/lkml/2016/12/21/
>      Fix a '\n' missing in a error message in arch_timer_mem_init.
>      Add "request_mem_region" for ioremapping cntbase, according to
>      f947ee1 clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map()
>      Rebase to 4.9.0-gfb779ff
>
> v18: https://lkml.org/lkml/2016/12/8/446
>      Fix 8/15 patch problem of "int ret;" in arch_timer_acpi_init.
>      Rebase to 4.9.0-rc8-g9269898
>
> v17: https://lkml.org/lkml/2016/11/25/140
>      Take out some cleanups from 4/15.
>      Merge 5/15 and 6/15, improve PPI determination code,
>      improve commit message.
>      Rework counter frequency detection.
>      Move arch_timer_needs_of_probing into DT init call.
>      Move Platform Timer scan loop back to timer init call to avoid allocating
>      and free memory.
>      Improve all the exported functions' comment.
>
> v16: https://lkml.org/lkml/2016/11/16/268
>      Fix patchset problem about static enum ppi_nr of 01/13 in v15.
>      Refactor arch_timer_detect_rate.
>      Refactor arch_timer_needs_probing.
>
> v15: https://lkml.org/lkml/2016/11/15/366
>      Re-order patches
>      Add arm_arch_timer refactoring patches to prepare for GTDT:
>          1. rename some  enums and defines, and some cleanups
>          2. separate out arch_timer_uses_ppi init code and fix a potential bug
>          3. Improve some new structs, refactor the timer init code.
>      Since the some structs have been changed, GTDT parser for memory-mapped
>      timer and SBSA Generic Watchdog timer have been update.
>
> v14: https://lkml.org/lkml/2016/9/28/573
>      Separate memory-mapped timer GTDT support into two patches
>          1. Refactor the timer init code to prepare for GTDT
>          2. Add GTDT support for memory-mapped timer
>
> v13: http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1231717.html
>      Improve arm_arch_timer code for memory-mapped
>      timer GTDT support, refactor original memory-mapped timer
>      dt support for reusing some common code.
>
> v12: https://lkml.org/lkml/2016/9/13/250
>      Rebase to latest Linux 4.8-rc6
>      Delete the confusing "skipping" in the error message.
>
> V11: https://lkml.org/lkml/2016/9/6/354
>      Rebase to latest Linux 4.8-rc5
>      Delete typedef (suggested by checkpatch.pl)
>
> V10: https://lkml.org/lkml/2016/7/26/215
>      Drop the "readq" patch.
>      Rebase to latest Linux 4.7.
>
> V9: https://lkml.org/lkml/2016/7/25/345
>     Improve pr_err message in acpi gtdt driver.
>     Update Commit message for 7/9
>     shorten the irq mapping function name
>     Improve GTDT driver for memory-mapped timer
>
> v8: https://lkml.org/lkml/2016/7/19/660
>     Improve "pr_fmt(fmt)" definition: add "ACPI" in front of "GTDT",
>     and also improve printk message.
>     Simplify is_timer_block and is_watchdog.
>     Merge acpi_gtdt_desc_init and gtdt_arch_timer_init into acpi_gtdt_init();
>     Delete __init in include/linux/acpi.h for GTDT API
>     Make ARM64 select GTDT.
>     Delete "#include <linux/module.h>" from acpi_gtdt.c
>     Simplify GT block parse code.
>
> v7: https://lkml.org/lkml/2016/7/13/769
>     Move the GTDT driver to drivers/acpi/arm64
>     Add add the ARM64-specific ACPI Support maintainers in MAINTAINERS
>     Merge 3 patches of GTDT parser driver.
>     Fix the for_each_platform_timer bug.
>
> v6: https://lkml.org/lkml/2016/6/29/580
>     split the GTDT driver to 4 parts: basic, arch_timer, memory-mapped timer,
>     and SBSA Generic Watchdog timer
>     Improve driver by suggestions and example code from Daniel Lezcano
>
> v5: https://lkml.org/lkml/2016/5/24/356
>     Sorting out all patches, simplify the API of GTDT driver:
>     GTDT driver just fills the data struct for arm_arch_timer driver.
>
> v4: https://lists.linaro.org/pipermail/linaro-acpi/2016-March/006667.html
>     Delete the kvm relevant patches
>     Separate two patches for sorting out the code for arm_arch_timer.
>     Improve irq info export code to allow missing irq info in GTDT table.
>
> v3: https://lkml.org/lkml/2016/2/1/658
>     Improve GTDT driver code:
>       (1)improve pr_* by defining pr_fmt(fmt)
>       (2)simplify gtdt_sbsa_gwdt_init
>       (3)improve gtdt_arch_timer_data_init, if table is NULL, it will try
>       to get GTDT table.
>     Move enum ppi_nr to arm_arch_timer.h, and add enum spi_nr.
>     Add arm_arch_timer get ppi from DT and GTDT support for kvm.
>
> v2: https://lkml.org/lkml/2015/12/2/10
>     Rebase to latest kernel version(4.4-rc3).
>     Fix the bug about the config problem,
>     use CONFIG_ACPI_GTDT instead of CONFIG_ACPI in arm_arch_timer.c
>
> v1: The first upstreaming version: https://lkml.org/lkml/2015/10/28/553
>
> Fu Wei (15):
>   clocksource/drivers/arm_arch_timer: Move enums and defines to header
>     file
>   clocksource/drivers/arm_arch_timer: Add a new enum for spi type
>   clocksource/drivers/arm_arch_timer: Improve printk relevant code
>   clocksource/drivers/arm_arch_timer: rename some enums and defines.
>   clocksource/drivers/arm_arch_timer: rework PPI determination
>   clocksource/drivers/arm_arch_timer: Rework counter frequency
>     detection.
>   clocksource/drivers/arm_arch_timer: Refactor arch_timer_needs_probing
>   clocksource/drivers/arm_arch_timer: move arch_timer_needs_of_probing
>     into DT init call
>   clocksource/drivers/arm_arch_timer: Introduce some new structs to
>     prepare for GTDT
>   clocksource/drivers/arm_arch_timer: Refactor the timer init code to
>     prepare for GTDT
>   acpi/arm64: Add GTDT table parse driver
>   clocksource/drivers/arm_arch_timer: Simplify ACPI support code.
>   acpi/arm64: Add memory-mapped timer support in GTDT driver
>   clocksource/drivers/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            | 374 +++++++++++++++++++++++++++
>  drivers/clocksource/arm_arch_timer.c | 483 ++++++++++++++++++++---------------
>  drivers/watchdog/Kconfig             |   1 +
>  include/clocksource/arm_arch_timer.h |  45 +++-
>  include/linux/acpi.h                 |   7 +
>  virt/kvm/arm/hyp/timer-sr.c          |   6 +-
>  9 files changed, 712 insertions(+), 209 deletions(-)
>  create mode 100644 drivers/acpi/arm64/gtdt.c
>
> --
> 2.9.3
>



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

Re: [PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[Mark Rutland]

On Mon, Jan 16, 2017 at 02:26:54PM +0800, Fu Wei wrote:
> Hi Mark,
> 
> This v19 (I have mentioned it in my previous email) is the latest
> patchset which can be applied on v4.10-rc4 directly.
> 
> please review this patchset, thanks! :-)

Thanks for the pointer; I will look at this shortly.

Mark.

Re: [PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[Fu Wei]

Hi Mark,

On 16 January 2017 at 20:01, Mark Rutland <mark.rutland@arm.com> wrote:
> On Mon, Jan 16, 2017 at 02:26:54PM +0800, Fu Wei wrote:
>> Hi Mark,
>>
>> This v19 (I have mentioned it in my previous email) is the latest
>> patchset which can be applied on v4.10-rc4 directly.
>>
>> please review this patchset, thanks! :-)
>
> Thanks for the pointer; I will look at this shortly.

Great thanks, looking forward to your feedback! :-)

>
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

Re: [PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[Mark Rutland]

Hi,

On Wed, Dec 21, 2016 at 02:45:48PM +0800, fu.wei@linaro.org wrote:
> From: Fu Wei <fu.wei@linaro.org>
> 
> This patchset:
>     (1)Preparation for adding GTDT support in arm_arch_timer:
>         1. Move some enums and marcos to header file;
>         2. Add a new enum for spi type;
>         3. Improve printk relevant code;
>         4. Rename some enums and defines;

Can we please rework these first few patches into a series:

1. Clean up printk() usage
2. Rename the type macros
3. Rename the PPI enum & enum values
4. Move the type macro and PPI enum into a header
5. Add new enum for SPIs

Please leave CNTHCL_* as they originally were. It's not part of the
interface of the driver, and leaving them as they are will save us an
interdependency with KVM.

I'm happy to queue that immediately, as it's purely structural and
shouldn't have a functional impact anywhere. That will also shrink the
series a bit, and we can rebase the following patches atop of that.

>         5. Rework PPI determination;
>         6. Rework counter frequency detection;
>         7. Refactor arch_timer_needs_probing, move it into DT init call
>         8. Introduce some new structs and refactor the MMIO timer init code
>         for reusing some common code.

I'll review these in separate replies.

Thanks,
Mark.

Re: [PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[Fu Wei]

Hi Mark,

On 17 January 2017 at 01:00, Mark Rutland <mark.rutland@arm.com> wrote:
> Hi,
>
> On Wed, Dec 21, 2016 at 02:45:48PM +0800, fu.wei@linaro.org wrote:
>> From: Fu Wei <fu.wei@linaro.org>
>>
>> This patchset:
>>     (1)Preparation for adding GTDT support in arm_arch_timer:
>>         1. Move some enums and marcos to header file;
>>         2. Add a new enum for spi type;
>>         3. Improve printk relevant code;
>>         4. Rename some enums and defines;
>
> Can we please rework these first few patches into a series:
>
> 1. Clean up printk() usage
> 2. Rename the type macros
> 3. Rename the PPI enum & enum values
> 4. Move the type macro and PPI enum into a header
> 5. Add new enum for SPIs
>
> Please leave CNTHCL_* as they originally were. It's not part of the
> interface of the driver, and leaving them as they are will save us an
> interdependency with KVM.
>
> I'm happy to queue that immediately, as it's purely structural and
> shouldn't have a functional impact anywhere. That will also shrink the
> series a bit, and we can rebase the following patches atop of that.

Thanks for your suggestion, I have finished this improvement.
It will be in v20.

https://git.linaro.org/people/fu.wei/linux.git/log/?h=topic-gtdt-wakeup-timer_upstream_v20_devel

>
>>         5. Rework PPI determination;
>>         6. Rework counter frequency detection;
>>         7. Refactor arch_timer_needs_probing, move it into DT init call
>>         8. Introduce some new structs and refactor the MMIO timer init code
>>         for reusing some common code.
>
> I'll review these in separate replies.
>
> Thanks,
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat