[PATCH v6 09/10] clk: stm32: Fix ltdc's clock turn off by clk_disable_unused() after system enter shell
gabriel.fernandez at foss.st.com
gabriel.fernandez at foss.st.com
Fri Oct 22 02:10:14 PDT 2021
Hi Dillon,
You can add my Acked-by: Gabriel Fernandez <gabriel.fernandez at foss.st.com>
Best Regards
Gabriel
On 10/22/21 9:25 AM, Dillon Min wrote:
> Hi Gabriel
>
> I guess you are the maintainer of stm32 clk subsystem from [1], Could
> you help to review this patch, just give a brief of the history:
>
> - this patch was acked by Stephen Boyd at [2].
> - reviewed by Patrice Chotard at [3].
>
> Without this patch , the kernel will turn off ltdc's clk after the
> system reach shell.
>
> [1] https://lore.kernel.org/lkml/AM8PR10MB4785545DC980090C1E7D66B281009@AM8PR10MB4785.EURPRD10.PROD.OUTLOOK.COM/
>
> [2] https://lore.kernel.org/linux-arm-kernel/159056850835.88029.9264848839121822798@swboyd.mtv.corp.google.com/
>
> [3] https://lore.kernel.org/lkml/6915fa2a-e211-476f-8317-6825e280c322@foss.st.com/#t
>
> Best Regards
> Dillon
>
> On Tue, 19 Oct 2021 at 16:44, Dillon Min <dillon.minfei at gmail.com> wrote:
>>
>> stm32's clk driver register two ltdc gate clk to clk core by
>> clk_hw_register_gate() and clk_hw_register_composite()
>>
>> first: 'stm32f429_gates[]', clk name is 'ltdc', which no user to use.
>> second: 'stm32f429_aux_clk[]', clk name is 'lcd-tft', used by ltdc driver
>>
>> both of them point to the same offset of stm32's RCC register. after
>> kernel enter console, clk core turn off ltdc's clk as 'stm32f429_gates[]'
>> is no one to use. but, actually 'stm32f429_aux_clk[]' is in use.
>>
>> stm32f469/746/769 have the same issue, fix it.
>>
>> Fixes: daf2d117cbca ("clk: stm32f4: Add lcd-tft clock")
>> Acked-by: Stephen Boyd <sboyd at kernel.org>
>> Link: https://lore.kernel.org/linux-arm-kernel/1590564453-24499-7-git-send-email-dillon.minfei@gmail.com/
>> Link: https://lore.kernel.org/lkml/CAPTRvHkf0cK_4ZidM17rPo99gWDmxgqFt4CDUjqFFwkOeQeFDg@mail.gmail.com/
>> Signed-off-by: Dillon Min <dillon.minfei at gmail.com>
>> ---
>> v6: no change.
>>
>> drivers/clk/clk-stm32f4.c | 4 ----
>> 1 file changed, 4 deletions(-)
>>
>> diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c
>> index af46176ad053..473dfe632cc5 100644
>> --- a/drivers/clk/clk-stm32f4.c
>> +++ b/drivers/clk/clk-stm32f4.c
>> @@ -129,7 +129,6 @@ static const struct stm32f4_gate_data stm32f429_gates[] __initconst = {
>> { STM32F4_RCC_APB2ENR, 20, "spi5", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 21, "spi6", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 22, "sai1", "apb2_div" },
>> - { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
>> };
>>
>> static const struct stm32f4_gate_data stm32f469_gates[] __initconst = {
>> @@ -211,7 +210,6 @@ static const struct stm32f4_gate_data stm32f469_gates[] __initconst = {
>> { STM32F4_RCC_APB2ENR, 20, "spi5", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 21, "spi6", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 22, "sai1", "apb2_div" },
>> - { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
>> };
>>
>> static const struct stm32f4_gate_data stm32f746_gates[] __initconst = {
>> @@ -286,7 +284,6 @@ static const struct stm32f4_gate_data stm32f746_gates[] __initconst = {
>> { STM32F4_RCC_APB2ENR, 21, "spi6", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 22, "sai1", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 23, "sai2", "apb2_div" },
>> - { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
>> };
>>
>> static const struct stm32f4_gate_data stm32f769_gates[] __initconst = {
>> @@ -364,7 +361,6 @@ static const struct stm32f4_gate_data stm32f769_gates[] __initconst = {
>> { STM32F4_RCC_APB2ENR, 21, "spi6", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 22, "sai1", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 23, "sai2", "apb2_div" },
>> - { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
>> { STM32F4_RCC_APB2ENR, 30, "mdio", "apb2_div" },
>> };
>>
>> --
>> 2.7.4
>>
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