[PATCH] mmc: dw_mmc-rockchip: Add memory clock auto-gating support

[Shawn Lin]

在 2025/11/12 星期三 0:55, Ulf Hansson 写道:
> On Tue, 4 Nov 2025 at 08:41, Shawn Lin <shawn.lin at rock-chips.com> wrote:
>>
>> Per design recommendations, the memory clock can be gated when there
>> is no in-flight transfer, which helps save power. This feature is
>> introduced alongside internal phase support, and this patch enables it.
> 
> Just to make sure, does this work if the controller is used for SDIO
> and has SDIO irqs enabled?
> 
> Or perhaps that is taken care of in dw_mci_prepare_sdio_irq()?
> 

Yes, it works for SDIO case too.

>>
>> Signed-off-by: Shawn Lin <shawn.lin at rock-chips.com>
> 
> Kind regards
> Uffe
> 
>> ---
>>
>>   drivers/mmc/host/dw_mmc-rockchip.c | 6 ++++++
>>   1 file changed, 6 insertions(+)
>>
>> diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c
>> index 6813549..62c68cd 100644
>> --- a/drivers/mmc/host/dw_mmc-rockchip.c
>> +++ b/drivers/mmc/host/dw_mmc-rockchip.c
>> @@ -19,6 +19,8 @@
>>   #define RK3288_CLKGEN_DIV              2
>>   #define SDMMC_TIMING_CON0              0x130
>>   #define SDMMC_TIMING_CON1              0x134
>> +#define SDMMC_MISC_CON                 0x138
>> +#define MEM_CLK_AUTOGATE_ENABLE                BIT(5)
>>   #define ROCKCHIP_MMC_DELAY_SEL         BIT(10)
>>   #define ROCKCHIP_MMC_DEGREE_MASK       0x3
>>   #define ROCKCHIP_MMC_DEGREE_OFFSET     1
>> @@ -470,6 +472,7 @@ static int dw_mci_rk3576_parse_dt(struct dw_mci *host)
>>
>>   static int dw_mci_rockchip_init(struct dw_mci *host)
>>   {
>> +       struct dw_mci_rockchip_priv_data *priv = host->priv;
>>          int ret, i;
>>
>>          /* It is slot 8 on Rockchip SoCs */
>> @@ -494,6 +497,9 @@ static int dw_mci_rockchip_init(struct dw_mci *host)
>>                          dev_warn(host->dev, "no valid minimum freq: %d\n", ret);
>>          }
>>
>> +       if (priv->internal_phase)
>> +               mci_writel(host, MISC_CON, MEM_CLK_AUTOGATE_ENABLE);
>> +
>>          return 0;
>>   }
>>
>> --
>> 2.7.4
>>
>