Re: [PATCH] clk: tegra: mark TEGRA210_CLK_DBGAPB as always on

From: Jon Hunter
Date: Mon Mar 06 2017 - 05:01:56 EST



On 06/03/17 08:38, Peter De Schrijver wrote:
> On Thu, Mar 02, 2017 at 05:56:49PM +0000, Jon Hunter wrote:
>>
>> On 28/02/17 15:19, Peter De Schrijver wrote:
>>> This is needed to make the JTAG debugging interface work.
>>>
>>> Signed-off-by: Peter De Schrijver <pdeschrijver@xxxxxxxxxx>
>>> ---
>>> drivers/clk/tegra/clk-tegra210.c | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
>>> index 9a2512a..708f5f1 100644
>>> --- a/drivers/clk/tegra/clk-tegra210.c
>>> +++ b/drivers/clk/tegra/clk-tegra210.c
>>> @@ -2680,6 +2680,7 @@ static void tegra210_cpu_clock_resume(void)
>>> { TEGRA210_CLK_EMC, TEGRA210_CLK_CLK_MAX, 0, 1 },
>>> { TEGRA210_CLK_MSELECT, TEGRA210_CLK_CLK_MAX, 0, 1 },
>>> { TEGRA210_CLK_CSITE, TEGRA210_CLK_CLK_MAX, 0, 1 },
>>> + { TEGRA210_CLK_DBGAPB, TEGRA210_CLK_CLK_MAX, 0, 1 },
>>> { TEGRA210_CLK_TSENSOR, TEGRA210_CLK_CLK_M, 400000, 0 },
>>> { TEGRA210_CLK_I2C1, TEGRA210_CLK_PLL_P, 0, 0 },
>>> { TEGRA210_CLK_I2C2, TEGRA210_CLK_PLL_P, 0, 0 },
>>
>> Should there be some dependency on say CONFIG_DEBUG_KERNEL? I am not
>> sure we always want this on for all cases.
>
> Why would you not want it to be always on?

Purely for power reasons. I do not know how much power keeping this
clock running consumes, but I don't like the idea of clocks running all
the time when they are not needed.

Jon

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nvpublic