2012-11-20 00:27:26

by Stephen Warren

[permalink] [raw]
Subject: [PATCH V2 1/2] clocksource: add common of_clksrc_init() function

From: Stephen Warren <[email protected]>

It is desirable to move all clocksource drivers to drivers/clocksource,
yet each requires its own initialization function. We'd rather not
pollute <linux/> with a header for each function. Instead, create a
single of_clksrc_init() function which will determine which clocksource
driver to initialize based on device tree.

Based on a similar patch for drivers/irqchip by Thomas Petazzoni.

Signed-off-by: Stephen Warren <[email protected]>
---
v2: New patch.

This series is based on the ARM sys_timer rework that I reposted today.

I hope that these patches can be taken through arm-soc tree for 3.9;
I will repost them based on 3.8-rc1 at the appropriate time.
---
drivers/clocksource/Kconfig | 3 +++
drivers/clocksource/Makefile | 1 +
drivers/clocksource/clksrc-of.c | 37 +++++++++++++++++++++++++++++++++++++
drivers/clocksource/clksrc-of.h | 20 ++++++++++++++++++++
include/linux/clocksource.h | 2 ++
5 files changed, 63 insertions(+)
create mode 100644 drivers/clocksource/clksrc-of.c
create mode 100644 drivers/clocksource/clksrc-of.h

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index c9f67de..4f300c5 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -1,3 +1,6 @@
+config CLKSRC_OF
+ bool
+
config CLKSRC_I8253
bool

diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 24fb888..29017a3 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_CLKSRC_OF) += clksrc-of.o
obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o
obj-$(CONFIG_X86_CYCLONE_TIMER) += cyclone.o
obj-$(CONFIG_X86_PM_TIMER) += acpi_pm.o
diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c
new file mode 100644
index 0000000..aeec8d2
--- /dev/null
+++ b/drivers/clocksource/clksrc-of.c
@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/init.h>
+#include <linux/of.h>
+
+#include "clksrc-of.h"
+
+static const struct of_device_id clksrc_of_match[] __initconst = {
+ { }
+};
+
+void __init clocksource_of_init(void)
+{
+ struct device_node *np;
+ const struct of_device_id *match;
+ void (*init_func)(void);
+
+ for_each_matching_node(np, clksrc_of_match) {
+ match = of_match_node(clksrc_of_match, np);
+ init_func = match->data;
+ init_func();
+ }
+}
diff --git a/drivers/clocksource/clksrc-of.h b/drivers/clocksource/clksrc-of.h
new file mode 100644
index 0000000..4e2191a
--- /dev/null
+++ b/drivers/clocksource/clksrc-of.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _CLKSRC_OF_H
+#define _CLKSRC_OF_H
+
+#endif
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 4dceaf8..a063b84 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -332,4 +332,6 @@ extern int clocksource_mmio_init(void __iomem *, const char *,

extern int clocksource_i8253_init(void);

+extern void clocksource_of_init(void);
+
#endif /* _LINUX_CLOCKSOURCE_H */
--
1.7.10.4


2012-11-20 00:27:42

by Stephen Warren

[permalink] [raw]
Subject: [PATCH V2 2/2] ARM: tegra: move timer.c to drivers/clocksource/

From: Stephen Warren <[email protected]>

Move arch/arm/mach-tegra/timer.c to drivers/clocksource/tegra20_timer.c
so that the code is co-located with other clocksource drivers, and to
reduce the size of the mach-tegra directory.

Signed-off-by: Stephen Warren <[email protected]>
---
v2: Rebase on ARM sys_timer rework, and addition of clocksource_of_init().
---
arch/arm/Kconfig | 1 +
arch/arm/mach-tegra/Makefile | 1 -
arch/arm/mach-tegra/board-dt-tegra20.c | 3 ++-
arch/arm/mach-tegra/board-dt-tegra30.c | 3 ++-
arch/arm/mach-tegra/board.h | 1 -
drivers/clocksource/Makefile | 1 +
drivers/clocksource/clksrc-of.c | 4 ++++
drivers/clocksource/clksrc-of.h | 2 ++
.../mach-tegra/timer.c => drivers/clocksource/tegra20_timer.c | 6 ++----
9 files changed, 14 insertions(+), 8 deletions(-)
rename arch/arm/mach-tegra/timer.c => drivers/clocksource/tegra20_timer.c (98%)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 14f8160..9eb54f6 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -633,6 +633,7 @@ config ARCH_TEGRA
select ARCH_HAS_CPUFREQ
select CLKDEV_LOOKUP
select CLKSRC_MMIO
+ select CLKSRC_OF
select COMMON_CLK
select GENERIC_CLOCKEVENTS
select GENERIC_GPIO
diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile
index 6f224f7..6ab3ed5 100644
--- a/arch/arm/mach-tegra/Makefile
+++ b/arch/arm/mach-tegra/Makefile
@@ -2,7 +2,6 @@ obj-y += common.o
obj-y += io.o
obj-y += irq.o
obj-y += clock.o
-obj-y += timer.o
obj-y += fuse.o
obj-y += pmc.o
obj-y += flowctrl.o
diff --git a/arch/arm/mach-tegra/board-dt-tegra20.c b/arch/arm/mach-tegra/board-dt-tegra20.c
index 794a7bf..0bee85a 100644
--- a/arch/arm/mach-tegra/board-dt-tegra20.c
+++ b/arch/arm/mach-tegra/board-dt-tegra20.c
@@ -15,6 +15,7 @@
*
*/

+#include <linux/clocksource.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
@@ -194,7 +195,7 @@ DT_MACHINE_START(TEGRA_DT, "nVidia Tegra20 (Flattened Device Tree)")
.init_early = tegra20_init_early,
.init_irq = tegra_dt_init_irq,
.handle_irq = gic_handle_irq,
- .init_time = tegra_init_timer,
+ .init_time = clocksource_of_init,
.init_machine = tegra_dt_init,
.init_late = tegra_dt_init_late,
.restart = tegra_assert_system_reset,
diff --git a/arch/arm/mach-tegra/board-dt-tegra30.c b/arch/arm/mach-tegra/board-dt-tegra30.c
index 08d3b19..a2b6cf1 100644
--- a/arch/arm/mach-tegra/board-dt-tegra30.c
+++ b/arch/arm/mach-tegra/board-dt-tegra30.c
@@ -23,6 +23,7 @@
*
*/

+#include <linux/clocksource.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_address.h>
@@ -104,7 +105,7 @@ DT_MACHINE_START(TEGRA30_DT, "NVIDIA Tegra30 (Flattened Device Tree)")
.init_early = tegra30_init_early,
.init_irq = tegra_dt_init_irq,
.handle_irq = gic_handle_irq,
- .init_time = tegra_init_timer,
+ .init_time = clocksource_of_init,
.init_machine = tegra30_dt_init,
.init_late = tegra_init_late,
.restart = tegra_assert_system_reset,
diff --git a/arch/arm/mach-tegra/board.h b/arch/arm/mach-tegra/board.h
index 744cdd2..da8f5a3 100644
--- a/arch/arm/mach-tegra/board.h
+++ b/arch/arm/mach-tegra/board.h
@@ -55,5 +55,4 @@ static inline int harmony_pcie_init(void) { return 0; }

void __init tegra_paz00_wifikill_init(void);

-extern void tegra_init_timer(void);
#endif
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 29017a3..ecf37f3 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -16,5 +16,6 @@ obj-$(CONFIG_CLKSRC_NOMADIK_MTU) += nomadik-mtu.o
obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o
obj-$(CONFIG_ARMADA_370_XP_TIMER) += time-armada-370-xp.o
obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o
+obj-$(CONFIG_ARCH_TEGRA) += tegra20_timer.o

obj-$(CONFIG_CLKSRC_ARM_GENERIC) += arm_generic.o
diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c
index aeec8d2..328d18f 100644
--- a/drivers/clocksource/clksrc-of.c
+++ b/drivers/clocksource/clksrc-of.c
@@ -20,6 +20,10 @@
#include "clksrc-of.h"

static const struct of_device_id clksrc_of_match[] __initconst = {
+ {
+ .compatible = "nvidia,tegra20-timer",
+ .data = tegra20_init_timer,
+ },
{ }
};

diff --git a/drivers/clocksource/clksrc-of.h b/drivers/clocksource/clksrc-of.h
index 4e2191a..386644d 100644
--- a/drivers/clocksource/clksrc-of.h
+++ b/drivers/clocksource/clksrc-of.h
@@ -17,4 +17,6 @@
#ifndef _CLKSRC_OF_H
#define _CLKSRC_OF_H

+void tegra20_init_timer(void);
+
#endif
diff --git a/arch/arm/mach-tegra/timer.c b/drivers/clocksource/tegra20_timer.c
similarity index 98%
rename from arch/arm/mach-tegra/timer.c
rename to drivers/clocksource/tegra20_timer.c
index b0036e5..9d84096 100644
--- a/arch/arm/mach-tegra/timer.c
+++ b/drivers/clocksource/tegra20_timer.c
@@ -1,6 +1,4 @@
/*
- * arch/arch/mach-tegra/timer.c
- *
* Copyright (C) 2010 Google, Inc.
*
* Author:
@@ -33,7 +31,7 @@
#include <asm/smp_twd.h>
#include <asm/sched_clock.h>

-#include "board.h"
+#include "clksrc-of.h"

#define RTC_SECONDS 0x08
#define RTC_SHADOW_SECONDS 0x0c
@@ -168,7 +166,7 @@ static const struct of_device_id rtc_match[] __initconst = {
{}
};

-void __init tegra_init_timer(void)
+void __init tegra20_init_timer(void)
{
struct device_node *np;
struct clk *clk;
--
1.7.10.4

2012-11-20 00:48:30

by Josh Cartwright

[permalink] [raw]
Subject: Re: [PATCH V2 2/2] ARM: tegra: move timer.c to drivers/clocksource/

On Mon, Nov 19, 2012 at 05:27:17PM -0700, Stephen Warren wrote:
> From: Stephen Warren <[email protected]>
>
> Move arch/arm/mach-tegra/timer.c to drivers/clocksource/tegra20_timer.c
> so that the code is co-located with other clocksource drivers, and to
> reduce the size of the mach-tegra directory.
>
> Signed-off-by: Stephen Warren <[email protected]>
> ---
> v2: Rebase on ARM sys_timer rework, and addition of clocksource_of_init().
[..]
> diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c
> index aeec8d2..328d18f 100644
> --- a/drivers/clocksource/clksrc-of.c
> +++ b/drivers/clocksource/clksrc-of.c
> @@ -20,6 +20,10 @@
> #include "clksrc-of.h"
>
> static const struct of_device_id clksrc_of_match[] __initconst = {
> + {
> + .compatible = "nvidia,tegra20-timer",
> + .data = tegra20_init_timer,
> + },

Shouldn't this be wrapped in #if ARCH_TEGRA?

I had suggested this with Thomas Petazzoni's consolidated irq_chip patch
as well:

It seems like it would be a bit cleaner/easier to maintain if we relied
on the linker to stitch together a clksrc_of_match table, based on what
clocksources are being built into the image. With that approach, at
least, a public initialization header wouldn't have to be exposed, and
this central table wouldn't have to be maintained (as more clocksrcs are
added, I forsee [admittedly trivial] merge conflicts).

Thoughts?

Josh

2012-11-20 08:17:40

by Thomas Petazzoni

[permalink] [raw]
Subject: Re: [PATCH V2 2/2] ARM: tegra: move timer.c to drivers/clocksource/

Josh,

On Mon, 19 Nov 2012 18:50:36 -0600, Josh Cartwright wrote:

> I had suggested this with Thomas Petazzoni's consolidated irq_chip patch
> as well:
>
> It seems like it would be a bit cleaner/easier to maintain if we relied
> on the linker to stitch together a clksrc_of_match table, based on what
> clocksources are being built into the image. With that approach, at
> least, a public initialization header wouldn't have to be exposed, and
> this central table wouldn't have to be maintained (as more clocksrcs are
> added, I forsee [admittedly trivial] merge conflicts).

... and I indeed have a new version of my irqchip patches that indeed
use the linker to merge together the of_device_id entries!

Best regards,

Thomas
--
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

2012-11-20 18:58:44

by Stephen Warren

[permalink] [raw]
Subject: Re: [PATCH V2 2/2] ARM: tegra: move timer.c to drivers/clocksource/

On 11/19/2012 05:50 PM, Josh Cartwright wrote:
> On Mon, Nov 19, 2012 at 05:27:17PM -0700, Stephen Warren wrote:
>> From: Stephen Warren <[email protected]>
>>
>> Move arch/arm/mach-tegra/timer.c to drivers/clocksource/tegra20_timer.c
>> so that the code is co-located with other clocksource drivers, and to
>> reduce the size of the mach-tegra directory.
>>
>> Signed-off-by: Stephen Warren <[email protected]>
>> ---
>> v2: Rebase on ARM sys_timer rework, and addition of clocksource_of_init().
> [..]
>> diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c
>> index aeec8d2..328d18f 100644
>> --- a/drivers/clocksource/clksrc-of.c
>> +++ b/drivers/clocksource/clksrc-of.c
>> @@ -20,6 +20,10 @@
>> #include "clksrc-of.h"
>>
>> static const struct of_device_id clksrc_of_match[] __initconst = {
>> + {
>> + .compatible = "nvidia,tegra20-timer",
>> + .data = tegra20_init_timer,
>> + },
>
> Shouldn't this be wrapped in #if ARCH_TEGRA?

Yes.

> I had suggested this with Thomas Petazzoni's consolidated irq_chip patch
> as well:
>
> It seems like it would be a bit cleaner/easier to maintain if we relied
> on the linker to stitch together a clksrc_of_match table, based on what
> clocksources are being built into the image. With that approach, at
> least, a public initialization header wouldn't have to be exposed, and
> this central table wouldn't have to be maintained (as more clocksrcs are
> added, I forsee [admittedly trivial] merge conflicts).
>
> Thoughts?

I thought I'd wait for Thomas' revised patch and copy that, but it
turned out to be easier that I figured to implement. So, new revision
coming soon!