Subject: [PATCH 1/3] clk: rcar-h2: fix sd0/sd1 divisor table

From: [email-masked] (Ben Dooks)
Date: Wed, 05 Feb 2014 11:55:12 +0000

On 05/02/14 10:56, Laurent Pinchart wrote:
> Hi William,
>
> Thank you for the patch.
>
> On Tuesday 04 February 2014 18:17:36 William Towle wrote:
>> The clk_div_table for cpg_sd01_div_table[] concurs with the manual
>> but not with values found in the device itself (which are also the
>> same as the ones in arch/arm/mach-shmobile/clock-r8a7790.c).
>>
>> Update the clk-rcar-gen2.c driver to have the same table as the one
>> used by the mach-shmobile driver which work once further issues are
>> fixed in the clk-rcar-gen2.c driver.
>>
>> Part of the fix for the following error where the driver reports the
>> output as 1MHz but is really 97.5MHz:
>>      sh_mobile_sdhi ee100000.sd: mmc0 base at 0xee100000 clock rate 1 MHz
>>
>> [ben.dooks at codethink.co.uk: updated patch description]
>> Signed-off-by: William Towle <[email-masked]>
>> Reviewed-by: Ben Dooks <[email-masked]>
>> ---
>>   drivers/clk/shmobile/clk-rcar-gen2.c |    2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/clk/shmobile/clk-rcar-gen2.c
>> b/drivers/clk/shmobile/clk-rcar-gen2.c index a59ec21..df4a1e6 100644
>> --- a/drivers/clk/shmobile/clk-rcar-gen2.c
>> +++ b/drivers/clk/shmobile/clk-rcar-gen2.c
>> @@ -170,6 +170,8 @@ static const struct clk_div_table cpg_sdh_div_table[] =
>> { };
>>
>>   static const struct clk_div_table cpg_sd01_div_table[] = {
>> +	{  0,  2 }, {  1,  3 }, {  2,  4 }, {  3,  6 },
>> +	{  4,  8 },
>>   	{  5, 12 }, {  6, 16 }, {  7, 18 }, {  8, 24 },
>>   	{ 10, 36 }, { 11, 48 }, { 12, 10 }, {  0,  0 },
>
> With this applied the only difference between the sdh and sd0/1 dividers
> tables would be the { 12, 10 } entry, available for sd0/1 only. Given that the
> hardware does not match the documentation, could you check whether that entry
> is supported by sdh as well ? If so we could merge the two tables. Otherwise
> this patch looks good, could you please just reformat the table to avoid the
> mostly empty line in the middle ?

I would like feedback from Renesas on this issue if possible. I can
have a quick try at setting the clock value to 10 in u-boot and scope
it out and see what happens.

Magnus or Morimoto-san, is there a chance this could be reviewed by
someone in Renesas who has knowledge of the hardware block?

[PS, added Kuninori Morimoto to this[

-- 
Ben Dooks				http://www.codethink.co.uk/
Senior Engineer				Codethink - Providing Genius