Re: [PATCH v3 1/3] ARM: da850: fix infinite loop in clk_set_rate()

From: Sekhar Nori
Date: Mon Dec 05 2016 - 05:42:25 EST


On Monday 05 December 2016 04:02 PM, Bartosz Golaszewski wrote:
> 2016-12-05 11:15 GMT+01:00 Sekhar Nori <nsekhar@xxxxxx>:
>> On Monday 05 December 2016 03:39 PM, Bartosz Golaszewski wrote:
>>> The aemif clock is added twice to the lookup table in da850.c. This
>>> breaks the children list of pll0_sysclk3 as we're using the same list
>>> links in struct clk. When calling clk_set_rate(), we get stuck in
>>> propagate_rate().
>>>
>>> Create a separate clock for nand, inheriting the rate of the aemif
>>> clock and retrieve it in the davinci_nand module.
>>>
>>> Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
>>> ---
>>> arch/arm/mach-davinci/da850.c | 7 ++++++-
>>> 1 file changed, 6 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/arch/arm/mach-davinci/da850.c b/arch/arm/mach-davinci/da850.c
>>> index e770c97..c008e5e 100644
>>> --- a/arch/arm/mach-davinci/da850.c
>>> +++ b/arch/arm/mach-davinci/da850.c
>>> @@ -367,6 +367,11 @@ static struct clk aemif_clk = {
>>> .flags = ALWAYS_ENABLED,
>>> };
>>>
>>> +static struct clk aemif_nand_clk = {
>>> + .name = "nand",
>>> + .parent = &aemif_clk,
>>> +};
>>> +
>>> static struct clk usb11_clk = {
>>> .name = "usb11",
>>> .parent = &pll0_sysclk4,
>>> @@ -537,7 +542,7 @@ static struct clk_lookup da850_clks[] = {
>>> CLK("da830-mmc.0", NULL, &mmcsd0_clk),
>>> CLK("da830-mmc.1", NULL, &mmcsd1_clk),
>>> CLK("ti-aemif", NULL, &aemif_clk),
>>> - CLK(NULL, "aemif", &aemif_clk),
>>> + CLK(NULL, "aemif", &aemif_nand_clk),
>>
>> Why use a NULL device name here? Same question was asked on v2
>
> Eek, sorry, I missed that.

For next version, can you also add a comment on top of 'struct clk
aemif_nand_clk' explaining why its needed?

Thanks,
Sekhar