[PATCH v24 10/11] clocksource: arm_arch_timer: add GTDT support for memory-mapped timer

[fu . wei]

From: Fu Wei 

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 
Reviewed-by: Hanjun Guo 
[Mark: verify CNTFRQ, only register the first frame]
Signed-off-by: Mark Rutland 
---
 drivers/clocksource/arm_arch_timer.c | 78 ++--
 1 file changed, 75 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c 
b/drivers/clocksource/arm_arch_timer.c
index 05f2f7a..8981173 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1385,10 +1385,78 @@ 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_verify_cntfrq(struct arch_timer_mem *timer_mem)
+{
+   struct arch_timer_mem_frame *frame;
+   u32 rate;
+   int i;
+
+   for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) {
+   frame = _mem->frame[i];
+
+   if (!frame->valid)
+   continue;
+
+   rate = arch_timer_mem_frame_get_cntfrq(frame);
+   if (rate == arch_timer_rate)
+   continue;
+
+   pr_err(FW_BUG "CNTFRQ mismatch: frame @ %pa: (0x%08lx), CPU: 
(0x%08lx)\n",
+  >cntbase,
+  (unsigned long)rate, (unsigned long)arch_timer_rate);
+
+   return -EINVAL;
+   }
+
+   return 0;
+}
+
+static int __init arch_timer_mem_acpi_init(int platform_timer_count)
+{
+   struct arch_timer_mem *timers, *timer;
+   struct arch_timer_mem_frame *frame;
+   int timer_count, i, ret = 0;
+
+   timers = kcalloc(platform_timer_count, sizeof(*timers), GFP_KERNEL);
+   if (!timers)
+   return -ENOMEM;
+
+   ret = acpi_arch_timer_mem_init(timers, _count);
+   if (ret || !timer_count)
+   goto out;
+
+   for (i = 0; i < timer_count; i++) {
+   ret = arch_timer_mem_verify_cntfrq([i]);
+   if (ret) {
+   pr_err("Disabling MMIO timers due to CNTFRQ 
mismatch\n");
+   goto out;
+   }
+   }
+
+   /*
+* While unlikely, it's theoretically possible that none of the frames
+* in a timer expose the combination of feature we want.
+*/
+   for (i = i; i < timer_count; i++) {
+   timer = [i];
+
+   frame = arch_timer_mem_find_best_frame(timer);
+   if (frame)
+   break;
+   }
+
+   if (frame)
+   ret = arch_timer_mem_frame_register(frame);
+out:
+   kfree(timers);
+   return ret;
+}
+
+/* Initialize per-processor generic timer and memory-mapped timer(if present) 
*/
 static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 {
-   int ret;
+   int ret, platform_timer_count;
 
if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
pr_warn("already initialized, skipping\n");
@@ -1397,7 +1465,7 @@ 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, _timer_count);
if (ret) {
pr_err("Failed to init GTDT table.\n");
return ret;
@@ -1440,6 +1508,10 @@ static int __init arch_timer_acpi_init(struct 
acpi_table_header *table)
if (ret)
return ret;
 
+   if (platform_timer_count &&
+   arch_timer_mem_acpi_init(platform_timer_count))
+   pr_err("Failed to initialize memory-mapped timer.\n");
+
return arch_timer_common_init();
 }
 CLOCKSOURCE_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
-- 
2.9.3

[PATCH v24 10/11] clocksource: arm_arch_timer: add GTDT support for memory-mapped timer

[fu . wei]

From: Fu Wei 

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 
Reviewed-by: Hanjun Guo 
[Mark: verify CNTFRQ, only register the first frame]
Signed-off-by: Mark Rutland 
---
 drivers/clocksource/arm_arch_timer.c | 78 ++--
 1 file changed, 75 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c 
b/drivers/clocksource/arm_arch_timer.c
index 05f2f7a..8981173 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1385,10 +1385,78 @@ 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_verify_cntfrq(struct arch_timer_mem *timer_mem)
+{
+   struct arch_timer_mem_frame *frame;
+   u32 rate;
+   int i;
+
+   for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) {
+   frame = _mem->frame[i];
+
+   if (!frame->valid)
+   continue;
+
+   rate = arch_timer_mem_frame_get_cntfrq(frame);
+   if (rate == arch_timer_rate)
+   continue;
+
+   pr_err(FW_BUG "CNTFRQ mismatch: frame @ %pa: (0x%08lx), CPU: 
(0x%08lx)\n",
+  >cntbase,
+  (unsigned long)rate, (unsigned long)arch_timer_rate);
+
+   return -EINVAL;
+   }
+
+   return 0;
+}
+
+static int __init arch_timer_mem_acpi_init(int platform_timer_count)
+{
+   struct arch_timer_mem *timers, *timer;
+   struct arch_timer_mem_frame *frame;
+   int timer_count, i, ret = 0;
+
+   timers = kcalloc(platform_timer_count, sizeof(*timers), GFP_KERNEL);
+   if (!timers)
+   return -ENOMEM;
+
+   ret = acpi_arch_timer_mem_init(timers, _count);
+   if (ret || !timer_count)
+   goto out;
+
+   for (i = 0; i < timer_count; i++) {
+   ret = arch_timer_mem_verify_cntfrq([i]);
+   if (ret) {
+   pr_err("Disabling MMIO timers due to CNTFRQ 
mismatch\n");
+   goto out;
+   }
+   }
+
+   /*
+* While unlikely, it's theoretically possible that none of the frames
+* in a timer expose the combination of feature we want.
+*/
+   for (i = i; i < timer_count; i++) {
+   timer = [i];
+
+   frame = arch_timer_mem_find_best_frame(timer);
+   if (frame)
+   break;
+   }
+
+   if (frame)
+   ret = arch_timer_mem_frame_register(frame);
+out:
+   kfree(timers);
+   return ret;
+}
+
+/* Initialize per-processor generic timer and memory-mapped timer(if present) 
*/
 static int __init arch_timer_acpi_init(struct acpi_table_header *table)
 {
-   int ret;
+   int ret, platform_timer_count;
 
if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
pr_warn("already initialized, skipping\n");
@@ -1397,7 +1465,7 @@ 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, _timer_count);
if (ret) {
pr_err("Failed to init GTDT table.\n");
return ret;
@@ -1440,6 +1508,10 @@ static int __init arch_timer_acpi_init(struct 
acpi_table_header *table)
if (ret)
return ret;
 
+   if (platform_timer_count &&
+   arch_timer_mem_acpi_init(platform_timer_count))
+   pr_err("Failed to initialize memory-mapped timer.\n");
+
return arch_timer_common_init();
 }
 CLOCKSOURCE_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
-- 
2.9.3