diff mbox

clk: imx: fix ahb clock mux 1

Message ID 1461877623-26838-1-git-send-email-stefan@agner.ch (mailing list archive)
State New, archived
Headers show

Commit Message

Stefan Agner April 28, 2016, 9:07 p.m. UTC
The clock parent of the AHB root clock when using mux option 1
is the SYS PLL 270MHz clock. This is specified in  Table 5-11
Clock Root Table of the i.MX 7Dual Applications Processor
Reference Manual.

While it could be a documentation error, the 270MHz parent is
also mentioned in the boot ROM configuration in Table 6-28: The
clock is by default at 135MHz due to a POST_PODF value of 1
(=> divider of 2).

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
Hi Shawn,

I did not found a clock which was based on this clock which I
could measure externally... But the change is backed by the
documentation.

--
Stefan

 drivers/clk/imx/clk-imx7d.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Uwe Kleine-König April 29, 2016, 8:19 a.m. UTC | #1
Hello,

$Subject ~= s/imx/imx7/

Best regards
Uwe
Shawn Guo May 3, 2016, 8:32 a.m. UTC | #2
On Thu, Apr 28, 2016 at 02:07:03PM -0700, Stefan Agner wrote:
> The clock parent of the AHB root clock when using mux option 1
> is the SYS PLL 270MHz clock. This is specified in  Table 5-11
> Clock Root Table of the i.MX 7Dual Applications Processor
> Reference Manual.
> 
> While it could be a documentation error, the 270MHz parent is
> also mentioned in the boot ROM configuration in Table 6-28: The
> clock is by default at 135MHz due to a POST_PODF value of 1
> (=> divider of 2).
> 
> Signed-off-by: Stefan Agner <stefan@agner.ch>

Anson, Frank,

Can you guys confirm this change is correct?

Shawn

> ---
> Hi Shawn,
> 
> I did not found a clock which was based on this clock which I
> could measure externally... But the change is backed by the
> documentation.
> 
> --
> Stefan
> 
>  drivers/clk/imx/clk-imx7d.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/imx/clk-imx7d.c b/drivers/clk/imx/clk-imx7d.c
> index 7912be8..5229968 100644
> --- a/drivers/clk/imx/clk-imx7d.c
> +++ b/drivers/clk/imx/clk-imx7d.c
> @@ -56,7 +56,7 @@ static const char *nand_usdhc_bus_sel[] = { "osc", "pll_sys_pfd2_270m_clk",
>  	"pll_sys_pfd2_135m_clk", "pll_sys_pfd6_clk", "pll_enet_250m_clk",
>  	"pll_audio_main_clk", };
>  
> -static const char *ahb_channel_sel[] = { "osc", "pll_sys_pfd2_135m_clk",
> +static const char *ahb_channel_sel[] = { "osc", "pll_sys_pfd2_270m_clk",
>  	"pll_dram_533m_clk", "pll_sys_pfd0_392m_clk",
>  	"pll_enet_125m_clk", "pll_usb_main_clk", "pll_audio_main_clk",
>  	"pll_video_main_clk", };
> -- 
> 2.8.0
> 
>
Dong Aisheng May 3, 2016, 10:50 a.m. UTC | #3
Hi Shawn,

On Tue, May 3, 2016 at 4:32 PM, Shawn Guo <shawnguo@kernel.org> wrote:
> On Thu, Apr 28, 2016 at 02:07:03PM -0700, Stefan Agner wrote:
>> The clock parent of the AHB root clock when using mux option 1
>> is the SYS PLL 270MHz clock. This is specified in  Table 5-11
>> Clock Root Table of the i.MX 7Dual Applications Processor
>> Reference Manual.
>>
>> While it could be a documentation error, the 270MHz parent is
>> also mentioned in the boot ROM configuration in Table 6-28: The
>> clock is by default at 135MHz due to a POST_PODF value of 1
>> (=> divider of 2).
>>
>> Signed-off-by: Stefan Agner <stefan@agner.ch>
>
> Anson, Frank,
>
> Can you guys confirm this change is correct?
>

I just checked the doc,
it's correct the parent should be SYS_PLL_PFD2(270Mhz).
It's a documentation error of early version and it's already fixed
in latest internal doc.

Regards
Dong Aisheng

> Shawn
>
>> ---
>> Hi Shawn,
>>
>> I did not found a clock which was based on this clock which I
>> could measure externally... But the change is backed by the
>> documentation.
>>
>> --
>> Stefan
>>
>>  drivers/clk/imx/clk-imx7d.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/clk/imx/clk-imx7d.c b/drivers/clk/imx/clk-imx7d.c
>> index 7912be8..5229968 100644
>> --- a/drivers/clk/imx/clk-imx7d.c
>> +++ b/drivers/clk/imx/clk-imx7d.c
>> @@ -56,7 +56,7 @@ static const char *nand_usdhc_bus_sel[] = { "osc", "pll_sys_pfd2_270m_clk",
>>       "pll_sys_pfd2_135m_clk", "pll_sys_pfd6_clk", "pll_enet_250m_clk",
>>       "pll_audio_main_clk", };
>>
>> -static const char *ahb_channel_sel[] = { "osc", "pll_sys_pfd2_135m_clk",
>> +static const char *ahb_channel_sel[] = { "osc", "pll_sys_pfd2_270m_clk",
>>       "pll_dram_533m_clk", "pll_sys_pfd0_392m_clk",
>>       "pll_enet_125m_clk", "pll_usb_main_clk", "pll_audio_main_clk",
>>       "pll_video_main_clk", };
>> --
>> 2.8.0
>>
>>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Shawn Guo May 3, 2016, 12:36 p.m. UTC | #4
On Fri, Apr 29, 2016 at 10:19:01AM +0200, Uwe Kleine-König wrote:
> Hello,
> 
> $Subject ~= s/imx/imx7/

Updated the subject and applied the patch.

Shawn
Shawn Guo May 3, 2016, 12:37 p.m. UTC | #5
On Tue, May 03, 2016 at 06:50:21PM +0800, Dong Aisheng wrote:
> Hi Shawn,
> 
> On Tue, May 3, 2016 at 4:32 PM, Shawn Guo <shawnguo@kernel.org> wrote:
> > On Thu, Apr 28, 2016 at 02:07:03PM -0700, Stefan Agner wrote:
> >> The clock parent of the AHB root clock when using mux option 1
> >> is the SYS PLL 270MHz clock. This is specified in  Table 5-11
> >> Clock Root Table of the i.MX 7Dual Applications Processor
> >> Reference Manual.
> >>
> >> While it could be a documentation error, the 270MHz parent is
> >> also mentioned in the boot ROM configuration in Table 6-28: The
> >> clock is by default at 135MHz due to a POST_PODF value of 1
> >> (=> divider of 2).
> >>
> >> Signed-off-by: Stefan Agner <stefan@agner.ch>
> >
> > Anson, Frank,
> >
> > Can you guys confirm this change is correct?
> >
> 
> I just checked the doc,
> it's correct the parent should be SYS_PLL_PFD2(270Mhz).
> It's a documentation error of early version and it's already fixed
> in latest internal doc.

Thanks for the confirmation.

Shawn
diff mbox

Patch

diff --git a/drivers/clk/imx/clk-imx7d.c b/drivers/clk/imx/clk-imx7d.c
index 7912be8..5229968 100644
--- a/drivers/clk/imx/clk-imx7d.c
+++ b/drivers/clk/imx/clk-imx7d.c
@@ -56,7 +56,7 @@  static const char *nand_usdhc_bus_sel[] = { "osc", "pll_sys_pfd2_270m_clk",
 	"pll_sys_pfd2_135m_clk", "pll_sys_pfd6_clk", "pll_enet_250m_clk",
 	"pll_audio_main_clk", };
 
-static const char *ahb_channel_sel[] = { "osc", "pll_sys_pfd2_135m_clk",
+static const char *ahb_channel_sel[] = { "osc", "pll_sys_pfd2_270m_clk",
 	"pll_dram_533m_clk", "pll_sys_pfd0_392m_clk",
 	"pll_enet_125m_clk", "pll_usb_main_clk", "pll_audio_main_clk",
 	"pll_video_main_clk", };