Re: [RFC PATCH v3.1 18/27] mmc: sdhci-uhs2: add clock operations

[AKASHI Takahiro]

On Thu, Nov 26, 2020 at 10:17:59AM +0200, Adrian Hunter wrote:
> On 6/11/20 4:27 am, AKASHI Takahiro wrote:
> > This is a sdhci version of mmc's uhs2_[enable|disable]_clk operations.
> > 
> > Signed-off-by: Ben Chuang 
> > Signed-off-by: AKASHI Takahiro 
> > ---
> >  drivers/mmc/host/sdhci-uhs2.c | 41 +++
> >  1 file changed, 41 insertions(+)
> > 
> > diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> > index 994dff967e85..55362ace1857 100644
> > --- a/drivers/mmc/host/sdhci-uhs2.c
> > +++ b/drivers/mmc/host/sdhci-uhs2.c
> > @@ -11,6 +11,7 @@
> >   */
> >  
> >  #include 
> > +#include 
> >  #include 
> >  
> >  #include "sdhci.h"
> > @@ -385,6 +386,42 @@ void sdhci_uhs2_set_ios(struct mmc_host *mmc, struct 
> > mmc_ios *ios)
> > __sdhci_uhs2_set_ios(mmc, ios);
> >  }
> >  
> > +static void sdhci_uhs2_disable_clk(struct mmc_host *mmc)
> > +{
> > +struct sdhci_host *host = mmc_priv(mmc);
> > +   u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > +
> > +   clk &= ~SDHCI_CLOCK_CARD_EN;
> > +   sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > +}
> > +
> > +static void sdhci_uhs2_enable_clk(struct mmc_host *mmc)
> > +{
> > +struct sdhci_host *host = mmc_priv(mmc);
> > +   u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > +   ktime_t timeout;
> > +
> > +   clk |= SDHCI_CLOCK_CARD_EN;
> > +   sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > +
> > +   /* Wait max 20 ms */
> > +   timeout = ktime_add_ms(ktime_get(), 20);
> > +   while (1) {
> > +   bool timedout = ktime_after(ktime_get(), timeout);
> > +
> > +   clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> 
> Can use read_poll_timeout(sdhci_readw,..., host, SDHCI_CLOCK_CONTROL)

Okay.

-Takahiro Akashi

> > +   if (clk & SDHCI_CLOCK_INT_STABLE)
> > +   break;
> > +   if (timedout) {
> > +   pr_err("%s: Internal clock never stabilised.\n",
> > +  mmc_hostname(host->mmc));
> > +   sdhci_dumpregs(host);
> > +   return;
> > +   }
> > +   udelay(10);
> > +   }
> > +}
> > +
> >  
> > /*\
> >   * 
> >   *
> >   * Driver init/exit
> >   *
> > @@ -556,6 +593,10 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host 
> > *host)
> >  
> > if (!host->mmc_host_ops.uhs2_detect_init)
> > host->mmc_host_ops.uhs2_detect_init = sdhci_uhs2_do_detect_init;
> > +   if (!host->mmc_host_ops.uhs2_disable_clk)
> > +   host->mmc_host_ops.uhs2_disable_clk = sdhci_uhs2_disable_clk;
> > +   if (!host->mmc_host_ops.uhs2_enable_clk)
> > +   host->mmc_host_ops.uhs2_enable_clk = sdhci_uhs2_enable_clk;
> >  
> > return 0;
> >  }
> > 
> 

Re: [RFC PATCH v3.1 18/27] mmc: sdhci-uhs2: add clock operations

[Adrian Hunter]

On 6/11/20 4:27 am, AKASHI Takahiro wrote:
> This is a sdhci version of mmc's uhs2_[enable|disable]_clk operations.
> 
> Signed-off-by: Ben Chuang 
> Signed-off-by: AKASHI Takahiro 
> ---
>  drivers/mmc/host/sdhci-uhs2.c | 41 +++
>  1 file changed, 41 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index 994dff967e85..55362ace1857 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -11,6 +11,7 @@
>   */
>  
>  #include 
> +#include 
>  #include 
>  
>  #include "sdhci.h"
> @@ -385,6 +386,42 @@ void sdhci_uhs2_set_ios(struct mmc_host *mmc, struct 
> mmc_ios *ios)
>   __sdhci_uhs2_set_ios(mmc, ios);
>  }
>  
> +static void sdhci_uhs2_disable_clk(struct mmc_host *mmc)
> +{
> +struct sdhci_host *host = mmc_priv(mmc);
> + u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> +
> + clk &= ~SDHCI_CLOCK_CARD_EN;
> + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +}
> +
> +static void sdhci_uhs2_enable_clk(struct mmc_host *mmc)
> +{
> +struct sdhci_host *host = mmc_priv(mmc);
> + u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> + ktime_t timeout;
> +
> + clk |= SDHCI_CLOCK_CARD_EN;
> + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +
> + /* Wait max 20 ms */
> + timeout = ktime_add_ms(ktime_get(), 20);
> + while (1) {
> + bool timedout = ktime_after(ktime_get(), timeout);
> +
> + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);

Can use read_poll_timeout(sdhci_readw,..., host, SDHCI_CLOCK_CONTROL)

> + if (clk & SDHCI_CLOCK_INT_STABLE)
> + break;
> + if (timedout) {
> + pr_err("%s: Internal clock never stabilised.\n",
> +mmc_hostname(host->mmc));
> + sdhci_dumpregs(host);
> + return;
> + }
> + udelay(10);
> + }
> +}
> +
>  
> /*\
>   *   
> *
>   * Driver init/exit  
> *
> @@ -556,6 +593,10 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host 
> *host)
>  
>   if (!host->mmc_host_ops.uhs2_detect_init)
>   host->mmc_host_ops.uhs2_detect_init = sdhci_uhs2_do_detect_init;
> + if (!host->mmc_host_ops.uhs2_disable_clk)
> + host->mmc_host_ops.uhs2_disable_clk = sdhci_uhs2_disable_clk;
> + if (!host->mmc_host_ops.uhs2_enable_clk)
> + host->mmc_host_ops.uhs2_enable_clk = sdhci_uhs2_enable_clk;
>  
>   return 0;
>  }
>