[PATCH v21 12/13] clocksource: arm_arch_timer: add GTDT support for memory-mapped timer

From: fu.wei@linaro.org
To: rjw@rjwysocki.net, lenb@kernel.org, daniel.lezcano@linaro.org,
	tglx@linutronix.de, marc.zyngier@arm.com, mark.rutland@arm.com,
	lorenzo.pieralisi@arm.com, sudeep.holla@arm.com,
	hanjun.guo@linaro.org
Cc: linux-arm-kernel@lists.infradead.org,
	linaro-acpi@lists.linaro.org, linux-kernel@vger.kernel.org,
	linux-acpi@vger.kernel.org, rruigrok@codeaurora.org,
	harba@codeaurora.org, cov@codeaurora.org, timur@codeaurora.org,
	graeme.gregory@linaro.org, al.stone@linaro.org, jcm@redhat.com,
	wei@redhat.com, arnd@arndb.de, catalin.marinas@arm.com,
	will.deacon@arm.com, Suravee.Suthikulpanit@amd.com,
	leo.duran@amd.com, wim@iguana.be, linux@roeck-us.net,
	linux-watchdog@vger.kernel.org, tn@semihalf.com,
	christoffer.dall@linaro.org, julien.grall@arm.com,
	Fu Wei <fu.wei@linaro.org>
Subject: [PATCH v21 12/13] clocksource: arm_arch_timer: add GTDT support for memory-mapped timer
Date: Tue,  7 Feb 2017 02:50:14 +0800	[thread overview]
Message-ID: <20170206185015.12296-13-fu.wei@linaro.org> (raw)
In-Reply-To: <20170206185015.12296-1-fu.wei@linaro.org>

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

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

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
---
 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 35e0b66..44c55ec 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1159,10 +1159,35 @@ 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 + i);
+		if (!ret)
+			break;
+	}
+
+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");
@@ -1171,7 +1196,7 @@ 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;
@@ -1208,6 +1233,10 @@ 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
