[PATCH v5 01/44] dt-bindings: clock: Add new bindings for TI Davinci PLL clocks

David Lechner david at lechnology.com
Thu Jan 11 13:46:19 PST 2018


On 01/11/2018 03:34 PM, Adam Ford wrote:
> On Thu, Jan 11, 2018 at 3:04 PM, David Lechner <david at lechnology.com> wrote:
>> On 01/11/2018 02:58 PM, Adam Ford wrote:
>>>
>>> On Thu, Jan 11, 2018 at 2:04 PM, David Lechner <david at lechnology.com>
>>> wrote:
>>>>
>>>> On 01/11/2018 12:50 PM, Adam Ford wrote:
>>>>>
>>>>>
>>>>> On Thu, Jan 11, 2018 at 12:29 PM, David Lechner <david at lechnology.com>
>>>>> wrote:
>>>>>>
>>>>>>
>>>>>> If removing the "clk_ignore_unused" option causes the board to not
>>>>>> boot,
>>>>>> then we still have problems that need to be fixed, so please also test
>>>>>> without this option.
>>>>>
>>>>>
>>>>>
>>>>> Without this option, it still does not boot.  Without device tree it
>>>>> hangs after:
>>>>>
>>>>> [snip]
>>>>>
>>>>> NET: Registered protocol family 17
>>>>> Loading compiled-in X.509 certificates
>>>>> console [netcon0] enabled
>>>>> netconsole: network logging started
>>>>> davinci_emac davinci_emac.1: using random MAC addr: 5e:38:1a:1f:4f:77
>>>>> mmc0: host does not support reading read-only switch, assuming
>>>>> write-enable
>>>>> hctosys: unable to open rtc device (rtc0)
>>>>> mmc0: new high speed SDHC card at address b368
>>>>>
>>>>>
>>>>> With device tree it hangs after:
>>>>>
>>>>> [snip]
>>>>> mmc0: host does not support reading read-only switch, assuming
>>>>> write-enable
>>>>> mmc0: new high speed SDHC card at address b368
>>>>> mmcblk0: mmc0:b368 00000 3.75 GiB
>>>>>     mmcblk0: p1 p2
>>>>> pca953x 0-0020: 0-0020 supply vcc not found, using dummy regulator
>>>>> pca953x 0-0020: failed reading register
>>>>> pca953x: probe of 0-0020 failed with error -121
>>>>> console [netcon0] enabled
>>>>> netconsole: network logging started
>>>>> davinci_emac 1e20000.ethernet: incompatible machine/device type for
>>>>> reading mac address
>>>>> hctosys: unable to open rtc device (rtc0)
>>>>>
>>>>>
>>>>
>>>> Please try this change:
>>>>
>>>> diff --git a/drivers/clk/davinci/psc-da850.c
>>>> b/drivers/clk/davinci/psc-da850.c
>>>> index 3fd6b49..a526cc2 100644
>>>> --- a/drivers/clk/davinci/psc-da850.c
>>>> +++ b/drivers/clk/davinci/psc-da850.c
>>>> @@ -17,7 +17,7 @@ static const struct davinci_psc_clk_info
>>>> da850_psc0_info[]
>>>> __initconst = {
>>>>           LPSC(0, 0, tpcc0, pll0_sysclk2, LPSC_ALWAYS_ENABLED),
>>>>           LPSC(1, 0, tptc0, pll0_sysclk2, LPSC_ALWAYS_ENABLED),
>>>>           LPSC(2, 0, tptc1, pll0_sysclk2, LPSC_ALWAYS_ENABLED),
>>>> -       LPSC(3, 0, aemif, pll0_sysclk3, 0),
>>>> +       LPSC(3, 0, aemif, pll0_sysclk3, LPSC_ALWAYS_ENABLED),
>>>>           LPSC(4, 0, spi0, pll0_sysclk2, 0),
>>>>           LPSC(5, 0, mmcsd0, pll0_sysclk2, 0),
>>>>           LPSC(6, 0, aintc, pll0_sysclk4, LPSC_ALWAYS_ENABLED),
>>>>
>>>>
>>>>
>>>> If that does not work, try adding LPSC_ALWAYS_ENABLED to all of the
>>>> clocks
>>>> in this file and then eliminate them one by one until you find which one
>>>> is
>>>> preventing boot.
>>>>
>>> Unfortunately, that didn't work.  I switch all the entries in both
>>> tables that had a 0 to LPSC_ALWAYS_ENABLED, but no luck booting.
>>>
>>>> If it still does not boot, there is a similar DIVCLK_ALWAYS_ENABLED flag
>>>> in
>>>> drivers/clk/davinci/pll-da850.c that you can repeat the exercise with.
>>>> Add
>>>> DIVCLK_ALWAYS_ENABLED to all of the clocks there and then eliminate it
>>>> one
>>>> by one until you find the clock that is causing the problem.
>>>
>>>
>>> Still no good news.  I switched all the entries with a 0 to
>>> DIVCLK_ALWAYS_ENABLED and it still didn't finish booting.
>>>
>>> I wonder if Sekhar Nori might have some suggestions.  I didn't look at
>>> the code or try to understand it.  I just changed the settings.
>>>>
>>>>
>>
>> Even if a clock had another flag besides zero, you will need to add
>> LPSC_ALWAYS_ENABLED by or-ing it with the other flag.
>>
> 
> [snip]
> 
> 
> Thanks for clarifying.  I was able to make it work with the following patch:
> 
> diff --git a/drivers/clk/davinci/psc-da850.c b/drivers/clk/davinci/psc-da850.c
> index 3b4583d..a76b8682 100644
> --- a/drivers/clk/davinci/psc-da850.c
> +++ b/drivers/clk/davinci/psc-da850.c
> @@ -25,7 +25,7 @@ static const struct davinci_psc_clk_info
> da850_psc0_info[] __initconst = {
>          LPSC(9, 0, uart0, pll0_sysclk2, 0),
>          LPSC(13, 0, pruss, pll0_sysclk2, 0),
>          LPSC(14, 0, arm, pll0_sysclk6, LPSC_ALWAYS_ENABLED),
> -       LPSC(15, 1, dsp, pll0_sysclk1, LPSC_FORCE | LPSC_LOCAL_RESET),
> +       LPSC(15, 1, dsp, pll0_sysclk1, LPSC_FORCE | LPSC_LOCAL_RESET |
> LPSC_ALWAYS_ENABLED),
>          { }
>   };
> 
> 
> If you have an updated patch series with those two fixes, I add my
> name to the tested-by list.
> 
> 
>>
>>
> [snip]
>>

Great! Thanks again for testing.

Sekhar, have you had a chance to look at the rest of the patches in the
series?

I'll wait a bit before I send a v6 to see if any other comments come.




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