[PATCH 02/05] sh: arch earlytimer support

[PATCH 02/05] sh: arch earlytimer support

[Magnus Damm]

From: Magnus Damm <damm@igel.co.jp>

Extend the 32-bit SuperH timer code to register and probe
the earlytimer class of Early Platform Drivers.

This registers the sh_cmt driver if compiled-in.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
---

 arch/sh/kernel/time_32.c |    9 +++++++++
 1 file changed, 9 insertions(+)

--- 0001/arch/sh/kernel/time_32.c
+++ work/arch/sh/kernel/time_32.c	2009-04-15 16:59:31.000000000 +0900
@@ -17,6 +17,7 @@
 #include <linux/sched.h>
 #include <linux/clockchips.h>
 #include <linux/mc146818rtc.h>	/* for rtc_lock */
+#include <linux/platform_device.h>
 #include <linux/smp.h>
 #include <asm/clock.h>
 #include <asm/rtc.h>
@@ -233,6 +234,14 @@ void __init time_init(void)
 	 * initialized for us.
 	 */
 	sys_timer = get_sys_timer();
+
+	/* Make sure all compiled-in early timers register themselves.
+	 * Run probe() for one "earlytimer" device.
+	 */
+	early_platform_driver_register_all("earlytimer");
+	if (early_platform_driver_probe("earlytimer", 1, 0))
+		return;
+
 	if (unlikely(!sys_timer))
 		panic("System timer missing.\n");
 

Re: [PATCH 02/05] sh: arch earlytimer support

[Paul Mundt]

On Wed, Apr 15, 2009 at 07:50:12PM +0900, Magnus Damm wrote:
> --- 0001/arch/sh/kernel/time_32.c
> +++ work/arch/sh/kernel/time_32.c	2009-04-15 16:59:31.000000000 +0900
> @@ -233,6 +234,14 @@ void __init time_init(void)
>  	 * initialized for us.
>  	 */
>  	sys_timer = get_sys_timer();
> +
> +	/* Make sure all compiled-in early timers register themselves.
> +	 * Run probe() for one "earlytimer" device.
> +	 */
> +	early_platform_driver_register_all("earlytimer");
> +	if (early_platform_driver_probe("earlytimer", 1, 0))
> +		return;
> +
>  	if (unlikely(!sys_timer))
>  		panic("System timer missing.\n");
>  
What exactly is the plan for progression from here? If the CMT
clocksource and clockevent drivers are filling the role of the old CMT
driver, then the sys_timer stuff needs to be isolated. As it is now,
platforms that only contain the CMT will still need to use the sys_timer
version, especially if they don't have multiple channels.

Re: [PATCH 02/05] sh: arch earlytimer support

[Magnus Damm]

On Wed, Apr 15, 2009 at 8:42 PM, Paul Mundt <lethal@linux-sh.org> wrote:
> On Wed, Apr 15, 2009 at 07:50:12PM +0900, Magnus Damm wrote:
>> --- 0001/arch/sh/kernel/time_32.c
>> +++ work/arch/sh/kernel/time_32.c     2009-04-15 16:59:31.000000000 +0900
>> @@ -233,6 +234,14 @@ void __init time_init(void)
>>        * initialized for us.
>>        */
>>       sys_timer = get_sys_timer();
>> +
>> +     /* Make sure all compiled-in early timers register themselves.
>> +      * Run probe() for one "earlytimer" device.
>> +      */
>> +     early_platform_driver_register_all("earlytimer");
>> +     if (early_platform_driver_probe("earlytimer", 1, 0))
>> +             return;
>> +
>>       if (unlikely(!sys_timer))
>>               panic("System timer missing.\n");
>>
> What exactly is the plan for progression from here? If the CMT
> clocksource and clockevent drivers are filling the role of the old CMT
> driver, then the sys_timer stuff needs to be isolated. As it is now,
> platforms that only contain the CMT will still need to use the sys_timer
> version, especially if they don't have multiple channels.

Sorry about the unclear code. So the early platform stuff should be
moved up before get_sys_timer(). This way sys_timer will always be
NULL if earlytimer is used. I'll resend a new version.

/ magnus