Le 10/06/2015 15:55, Boris Brezillon a écrit :
> Hi Nicolas,
>
> On Wed, 10 Jun 2015 15:42:44 +0200
> Nicolas Ferre <nicolas.fe...@atmel.com> wrote:
>
>> As some more information is added to the PCR register, we'd better use
>> a copy of its content and modify just the peripheral-related bits.
>> Implement a read-modify-write for the enable() and disable() callbacks.
>>
>> Header file is also modified to have the PCR_DIV mask.
>>
>> Signed-off-by: Nicolas Ferre <nicolas.fe...@atmel.com>
>
> Apart from the below comment you can add my:
>
> Acked-by: Boris Brezillon <boris.brezil...@free-electrons.com>
>
>> ---
>> drivers/clk/at91/clk-peripheral.c | 19 +++++++++++++------
>> include/linux/clk/at91_pmc.h | 3 ++-
>> 2 files changed, 15 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/clk/at91/clk-peripheral.c
>> b/drivers/clk/at91/clk-peripheral.c
>> index 597fed423d7d..37e2fea14890 100644
>> --- a/drivers/clk/at91/clk-peripheral.c
>> +++ b/drivers/clk/at91/clk-peripheral.c
>> @@ -161,14 +161,17 @@ static int clk_sam9x5_peripheral_enable(struct clk_hw
>> *hw)
>> {
>> struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
>> struct at91_pmc *pmc = periph->pmc;
>> + u32 tmp;
>>
>> if (periph->id < PERIPHERAL_ID_MIN)
>> return 0;
>>
>> - pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID) |
>> - AT91_PMC_PCR_CMD |
>> - AT91_PMC_PCR_DIV(periph->div) |
>> - AT91_PMC_PCR_EN);
>> + pmc_lock(pmc);
>> + pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID));
>> + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_P_DIV;
>> + pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_PDIV(periph->div)
>> + | AT91_PMC_PCR_EN);
>> + pmc_unlock(pmc);
>> return 0;
>> }
>>
>> @@ -176,12 +179,16 @@ static void clk_sam9x5_peripheral_disable(struct
>> clk_hw *hw)
>> {
>> struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
>> struct at91_pmc *pmc = periph->pmc;
>> + u32 tmp;
>>
>> if (periph->id < PERIPHERAL_ID_MIN)
>> return;
>>
>> - pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID) |
>> - AT91_PMC_PCR_CMD);
>> + pmc_lock(pmc);
>> + pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID));
>> + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_EN;
>> + pmc_write(pmc, AT91_PMC_PCR, tmp);
>> + pmc_unlock(pmc);
>> }
>>
>> static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw)
>> diff --git a/include/linux/clk/at91_pmc.h b/include/linux/clk/at91_pmc.h
>> index 7669f7618f39..4685c3d62f94 100644
>> --- a/include/linux/clk/at91_pmc.h
>> +++ b/include/linux/clk/at91_pmc.h
>> @@ -184,7 +184,8 @@ extern void __iomem *at91_pmc_base;
>> #define AT91_PMC_PCR 0x10c /* Peripheral
>> Control Register [some SAM9 and SAMA5] */
>> #define AT91_PMC_PCR_PID (0x3f << 0) /*
>> Peripheral ID */
>> #define AT91_PMC_PCR_CMD (0x1 << 12) /*
>> Command (read=0, write=1) */
>> -#define AT91_PMC_PCR_DIV(n) ((n) << 16) /*
>> Divisor Value */
>> +#define AT91_PMC_PCR_P_DIV (0x3 << 16) /*
>> Divisor mask */
>
> How about renaming this macro into AT91_PMC_PCR_PDIV_MSK ?
> I know the macro names in this file are not consistent, but maybe it's
> time to choose appropriate names for new AT91_PMC macros.
Well, this is what I tried to find: consistency ;-)
It seems that other macros are like I did for this one: the pure name of
the field for the mask and some kind of other form of the name for a
value macro or a (usually useless) list of macro-per-value things.
For this one I added a "P" for peripheral which is not in the real name
of the register field. This is to differentiate it from the upcoming
GCK_DIV field...
Bye,
--
Nicolas Ferre
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