diff mbox

[v3,7/9] mmc: sdhci-msm: Implement set_clock callback for sdhci-msm

Message ID 1471581384-18961-8-git-send-email-riteshh@codeaurora.org (mailing list archive)
State Superseded, archived
Delegated to: Andy Gross
Headers show

Commit Message

Ritesh Harjani Aug. 19, 2016, 4:36 a.m. UTC
sdhci-msm controller may have different clk-rates for each
bus speed mode. Thus implement set_clock callback for
sdhci-msm driver.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
---
 drivers/mmc/host/sdhci-msm.c | 103 ++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 102 insertions(+), 1 deletion(-)

Comments

Adrian Hunter Aug. 19, 2016, 1:04 p.m. UTC | #1
On 19/08/16 07:36, Ritesh Harjani wrote:
> sdhci-msm controller may have different clk-rates for each
> bus speed mode. Thus implement set_clock callback for
> sdhci-msm driver.
> 
> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
> ---
>  drivers/mmc/host/sdhci-msm.c | 103 ++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 102 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 7c032c3..c0ad9c2 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>  	struct mmc_host *mmc;
>  	bool use_14lpp_dll_reset;
>  	struct sdhci_msm_pltfm_data *pdata;
> +	u32 clk_rate;
>  };
>  
>  /* Platform specific tuning */
> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct sdhci_host *host)
>  	return msm_host->pdata->clk_table[0];
>  }
>  
> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
> +					u32 req_clk)
> +{
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> +	int count = msm_host->pdata->clk_table_sz;
> +	unsigned int sel_clk = -1;
> +	int cnt;
> +
> +	if (req_clk < sdhci_msm_get_min_clock(host)) {
> +		sel_clk = sdhci_msm_get_min_clock(host);
> +		return sel_clk;
> +	}
> +
> +	for (cnt = 0; cnt < count; cnt++) {
> +		if (msm_host->pdata->clk_table[cnt] > req_clk) {
> +			break;
> +		} else if (msm_host->pdata->clk_table[cnt] == req_clk) {
> +			sel_clk = msm_host->pdata->clk_table[cnt];
> +			break;
> +		} else {
> +			sel_clk = msm_host->pdata->clk_table[cnt];
> +		}
> +	}

'else' is not needed after 'break' but can't this be simpler e.g.

static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host *msm_host, u32 req_clk)
{
	int count = msm_host->pdata->clk_table_sz;
	unsigned int sel_clk = -1;

	while (count--) {
		sel_clk = msm_host->pdata->clk_table[count];
		if (req_clk >= sel_clk)
			return sel_clk;
	}

	return sel_clk;
}


> +	return sel_clk;
> +}

Blank line needed

> +/**
> + * __sdhci_msm_set_clock - sdhci_msm clock control.
> + *
> + * Description:
> + * Implement MSM version of sdhci_set_clock.
> + * This is required since MSM controller does not
> + * use internal divider and instead directly control
> + * the GCC clock as per HW recommendation.
> + **/
> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
> +{
> +	u16 clk;
> +	unsigned long timeout;
> +
> +	host->mmc->actual_clock = 0;
> +
> +	sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
> +
> +	if (clock == 0)
> +		return;

Should set host->mmc->actual_clock to the actual rate somewhere.

> +
> +	/*
> +	 * MSM controller do not use clock divider.
> +	 * Thus read SDHCI_CLOCK_CONTROL and only enable
> +	 * clock with no divider value programmed.
> +	 */
> +	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> +
> +	clk |= SDHCI_CLOCK_INT_EN;
> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +
> +	/* Wait max 20 ms */
> +	timeout = 20;
> +	while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
> +		& SDHCI_CLOCK_INT_STABLE)) {
> +		if (timeout == 0) {
> +			pr_err("%s: Internal clock never stabilised.\n",
> +			       mmc_hostname(host->mmc));
> +			return;
> +		}
> +		timeout--;
> +		mdelay(1);
> +	}
> +
> +	clk |= SDHCI_CLOCK_CARD_EN;
> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +}
> +
> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
> +{
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> +	u32 msm_clock = 0;
> +	int rc = 0;
> +
> +	if (!clock)
> +		goto out;
> +
> +	if (clock != msm_host->clk_rate) {
> +		msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
> +		rc = clk_set_rate(msm_host->clk, msm_clock);
> +		if (rc) {
> +			pr_err("%s: failed to set clock at rate %u, requested clock rate %u\n",
> +				mmc_hostname(host->mmc), msm_clock, clock);
> +			goto out;
> +		}
> +		msm_host->clk_rate = clock;
> +		pr_debug("%s: setting clock at rate %lu\n",
> +			mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
> +	}
> +out:
> +	__sdhci_msm_set_clock(host, clock);
> +}
> +
>  static const struct of_device_id sdhci_msm_dt_match[] = {
>  	{ .compatible = "qcom,sdhci-msm-v4" },
>  	{},
> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>  static const struct sdhci_ops sdhci_msm_ops = {
>  	.platform_execute_tuning = sdhci_msm_execute_tuning,
>  	.reset = sdhci_reset,
> -	.set_clock = sdhci_set_clock,
> +	.set_clock = sdhci_msm_set_clock,
>  	.get_min_clock = sdhci_msm_get_min_clock,
>  	.get_max_clock = sdhci_msm_get_max_clock,
>  	.set_bus_width = sdhci_set_bus_width,
> 

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Ritesh Harjani Aug. 19, 2016, 1:31 p.m. UTC | #2
Hi,


On 8/19/2016 6:34 PM, Adrian Hunter wrote:
> On 19/08/16 07:36, Ritesh Harjani wrote:
>> sdhci-msm controller may have different clk-rates for each
>> bus speed mode. Thus implement set_clock callback for
>> sdhci-msm driver.
>>
>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
>> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
>> ---
>>  drivers/mmc/host/sdhci-msm.c | 103 ++++++++++++++++++++++++++++++++++++++++++-
>>  1 file changed, 102 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>> index 7c032c3..c0ad9c2 100644
>> --- a/drivers/mmc/host/sdhci-msm.c
>> +++ b/drivers/mmc/host/sdhci-msm.c
>> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>>  	struct mmc_host *mmc;
>>  	bool use_14lpp_dll_reset;
>>  	struct sdhci_msm_pltfm_data *pdata;
>> +	u32 clk_rate;
>>  };
>>
>>  /* Platform specific tuning */
>> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct sdhci_host *host)
>>  	return msm_host->pdata->clk_table[0];
>>  }
>>
>> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
>> +					u32 req_clk)
>> +{
>> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>> +	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>> +	int count = msm_host->pdata->clk_table_sz;
>> +	unsigned int sel_clk = -1;
>> +	int cnt;
>> +
>> +	if (req_clk < sdhci_msm_get_min_clock(host)) {
>> +		sel_clk = sdhci_msm_get_min_clock(host);
>> +		return sel_clk;
>> +	}
>> +
>> +	for (cnt = 0; cnt < count; cnt++) {
>> +		if (msm_host->pdata->clk_table[cnt] > req_clk) {
>> +			break;
>> +		} else if (msm_host->pdata->clk_table[cnt] == req_clk) {
>> +			sel_clk = msm_host->pdata->clk_table[cnt];
>> +			break;
>> +		} else {
>> +			sel_clk = msm_host->pdata->clk_table[cnt];
>> +		}
>> +	}
>
> 'else' is not needed after 'break' but can't this be simpler e.g.
>
> static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host *msm_host, u32 req_clk)
> {
> 	int count = msm_host->pdata->clk_table_sz;
> 	unsigned int sel_clk = -1;
>
> 	while (count--) {
> 		sel_clk = msm_host->pdata->clk_table[count];
> 		if (req_clk >= sel_clk)
> 			return sel_clk;
> 	}
>
> 	return sel_clk;
> }

Ok, sure I will check and get back on this.


>
>
>> +	return sel_clk;
>> +}
>
> Blank line needed
Ok done.

>
>> +/**
>> + * __sdhci_msm_set_clock - sdhci_msm clock control.
>> + *
>> + * Description:
>> + * Implement MSM version of sdhci_set_clock.
>> + * This is required since MSM controller does not
>> + * use internal divider and instead directly control
>> + * the GCC clock as per HW recommendation.
>> + **/
>> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>> +{
>> +	u16 clk;
>> +	unsigned long timeout;
>> +
>> +	host->mmc->actual_clock = 0;
>> +
>> +	sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
>> +
>> +	if (clock == 0)
>> +		return;
>
> Should set host->mmc->actual_clock to the actual rate somewhere.
Since MSM controller does not uses divider then there is no need of 
having actual clock since it should be same as host->clock.

That's why I had kept it 0 intentionally. But I will add a comment
here then.

>
>> +
>> +	/*
>> +	 * MSM controller do not use clock divider.
>> +	 * Thus read SDHCI_CLOCK_CONTROL and only enable
>> +	 * clock with no divider value programmed.
>> +	 */
>> +	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>> +
>> +	clk |= SDHCI_CLOCK_INT_EN;
>> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>> +
>> +	/* Wait max 20 ms */
>> +	timeout = 20;
>> +	while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
>> +		& SDHCI_CLOCK_INT_STABLE)) {
>> +		if (timeout == 0) {
>> +			pr_err("%s: Internal clock never stabilised.\n",
>> +			       mmc_hostname(host->mmc));
>> +			return;
>> +		}
>> +		timeout--;
>> +		mdelay(1);
>> +	}
>> +
>> +	clk |= SDHCI_CLOCK_CARD_EN;
>> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>> +}
>> +
>> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>> +{
>> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>> +	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>> +	u32 msm_clock = 0;
>> +	int rc = 0;
>> +
>> +	if (!clock)
>> +		goto out;
>> +
>> +	if (clock != msm_host->clk_rate) {
>> +		msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>> +		rc = clk_set_rate(msm_host->clk, msm_clock);
>> +		if (rc) {
>> +			pr_err("%s: failed to set clock at rate %u, requested clock rate %u\n",
>> +				mmc_hostname(host->mmc), msm_clock, clock);
>> +			goto out;
>> +		}
>> +		msm_host->clk_rate = clock;
>> +		pr_debug("%s: setting clock at rate %lu\n",
>> +			mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
>> +	}
>> +out:
>> +	__sdhci_msm_set_clock(host, clock);
>> +}
>> +
>>  static const struct of_device_id sdhci_msm_dt_match[] = {
>>  	{ .compatible = "qcom,sdhci-msm-v4" },
>>  	{},
>> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>>  static const struct sdhci_ops sdhci_msm_ops = {
>>  	.platform_execute_tuning = sdhci_msm_execute_tuning,
>>  	.reset = sdhci_reset,
>> -	.set_clock = sdhci_set_clock,
>> +	.set_clock = sdhci_msm_set_clock,
>>  	.get_min_clock = sdhci_msm_get_min_clock,
>>  	.get_max_clock = sdhci_msm_get_max_clock,
>>  	.set_bus_width = sdhci_set_bus_width,
>>
>
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Adrian Hunter Aug. 22, 2016, 6:20 a.m. UTC | #3
On 19/08/16 16:31, Ritesh Harjani wrote:
> Hi,
> 
> 
> On 8/19/2016 6:34 PM, Adrian Hunter wrote:
>> On 19/08/16 07:36, Ritesh Harjani wrote:
>>> sdhci-msm controller may have different clk-rates for each
>>> bus speed mode. Thus implement set_clock callback for
>>> sdhci-msm driver.
>>>
>>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
>>> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
>>> ---
>>>  drivers/mmc/host/sdhci-msm.c | 103
>>> ++++++++++++++++++++++++++++++++++++++++++-
>>>  1 file changed, 102 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>>> index 7c032c3..c0ad9c2 100644
>>> --- a/drivers/mmc/host/sdhci-msm.c
>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>>>      struct mmc_host *mmc;
>>>      bool use_14lpp_dll_reset;
>>>      struct sdhci_msm_pltfm_data *pdata;
>>> +    u32 clk_rate;
>>>  };
>>>
>>>  /* Platform specific tuning */
>>> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct
>>> sdhci_host *host)
>>>      return msm_host->pdata->clk_table[0];
>>>  }
>>>
>>> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
>>> +                    u32 req_clk)
>>> +{
>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>> +    int count = msm_host->pdata->clk_table_sz;
>>> +    unsigned int sel_clk = -1;
>>> +    int cnt;
>>> +
>>> +    if (req_clk < sdhci_msm_get_min_clock(host)) {
>>> +        sel_clk = sdhci_msm_get_min_clock(host);
>>> +        return sel_clk;
>>> +    }
>>> +
>>> +    for (cnt = 0; cnt < count; cnt++) {
>>> +        if (msm_host->pdata->clk_table[cnt] > req_clk) {
>>> +            break;
>>> +        } else if (msm_host->pdata->clk_table[cnt] == req_clk) {
>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>> +            break;
>>> +        } else {
>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>> +        }
>>> +    }
>>
>> 'else' is not needed after 'break' but can't this be simpler e.g.
>>
>> static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host
>> *msm_host, u32 req_clk)
>> {
>>     int count = msm_host->pdata->clk_table_sz;
>>     unsigned int sel_clk = -1;
>>
>>     while (count--) {
>>         sel_clk = msm_host->pdata->clk_table[count];
>>         if (req_clk >= sel_clk)
>>             return sel_clk;
>>     }
>>
>>     return sel_clk;
>> }
> 
> Ok, sure I will check and get back on this.
> 
> 
>>
>>
>>> +    return sel_clk;
>>> +}
>>
>> Blank line needed
> Ok done.
> 
>>
>>> +/**
>>> + * __sdhci_msm_set_clock - sdhci_msm clock control.
>>> + *
>>> + * Description:
>>> + * Implement MSM version of sdhci_set_clock.
>>> + * This is required since MSM controller does not
>>> + * use internal divider and instead directly control
>>> + * the GCC clock as per HW recommendation.
>>> + **/
>>> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>>> +{
>>> +    u16 clk;
>>> +    unsigned long timeout;
>>> +
>>> +    host->mmc->actual_clock = 0;
>>> +
>>> +    sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
>>> +
>>> +    if (clock == 0)
>>> +        return;
>>
>> Should set host->mmc->actual_clock to the actual rate somewhere.
> Since MSM controller does not uses divider then there is no need of having
> actual clock since it should be same as host->clock.

Ok, so sdhci_msm_get_msm_clk_rate() is not the actual clock rate?

> 
> That's why I had kept it 0 intentionally. But I will add a comment
> here then.
> 
>>
>>> +
>>> +    /*
>>> +     * MSM controller do not use clock divider.
>>> +     * Thus read SDHCI_CLOCK_CONTROL and only enable
>>> +     * clock with no divider value programmed.
>>> +     */
>>> +    clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>> +
>>> +    clk |= SDHCI_CLOCK_INT_EN;
>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>> +
>>> +    /* Wait max 20 ms */
>>> +    timeout = 20;
>>> +    while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
>>> +        & SDHCI_CLOCK_INT_STABLE)) {
>>> +        if (timeout == 0) {
>>> +            pr_err("%s: Internal clock never stabilised.\n",
>>> +                   mmc_hostname(host->mmc));
>>> +            return;
>>> +        }
>>> +        timeout--;
>>> +        mdelay(1);
>>> +    }
>>> +
>>> +    clk |= SDHCI_CLOCK_CARD_EN;
>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>> +}
>>> +
>>> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int
>>> clock)
>>> +{
>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>> +    u32 msm_clock = 0;
>>> +    int rc = 0;
>>> +
>>> +    if (!clock)
>>> +        goto out;
>>> +
>>> +    if (clock != msm_host->clk_rate) {
>>> +        msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>>> +        rc = clk_set_rate(msm_host->clk, msm_clock);
>>> +        if (rc) {
>>> +            pr_err("%s: failed to set clock at rate %u, requested clock
>>> rate %u\n",
>>> +                mmc_hostname(host->mmc), msm_clock, clock);
>>> +            goto out;
>>> +        }
>>> +        msm_host->clk_rate = clock;
>>> +        pr_debug("%s: setting clock at rate %lu\n",
>>> +            mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
>>> +    }
>>> +out:
>>> +    __sdhci_msm_set_clock(host, clock);
>>> +}
>>> +
>>>  static const struct of_device_id sdhci_msm_dt_match[] = {
>>>      { .compatible = "qcom,sdhci-msm-v4" },
>>>      {},
>>> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>>>  static const struct sdhci_ops sdhci_msm_ops = {
>>>      .platform_execute_tuning = sdhci_msm_execute_tuning,
>>>      .reset = sdhci_reset,
>>> -    .set_clock = sdhci_set_clock,
>>> +    .set_clock = sdhci_msm_set_clock,
>>>      .get_min_clock = sdhci_msm_get_min_clock,
>>>      .get_max_clock = sdhci_msm_get_max_clock,
>>>      .set_bus_width = sdhci_set_bus_width,
>>>
>>
> 

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Ritesh Harjani Aug. 22, 2016, 9:07 a.m. UTC | #4
Hi Adrian,


On 8/22/2016 11:50 AM, Adrian Hunter wrote:
> On 19/08/16 16:31, Ritesh Harjani wrote:
>> Hi,
>>
>>
>> On 8/19/2016 6:34 PM, Adrian Hunter wrote:
>>> On 19/08/16 07:36, Ritesh Harjani wrote:
>>>> sdhci-msm controller may have different clk-rates for each
>>>> bus speed mode. Thus implement set_clock callback for
>>>> sdhci-msm driver.
>>>>
>>>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
>>>> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
>>>> ---
>>>>  drivers/mmc/host/sdhci-msm.c | 103
>>>> ++++++++++++++++++++++++++++++++++++++++++-
>>>>  1 file changed, 102 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>>>> index 7c032c3..c0ad9c2 100644
>>>> --- a/drivers/mmc/host/sdhci-msm.c
>>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>>> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>>>>      struct mmc_host *mmc;
>>>>      bool use_14lpp_dll_reset;
>>>>      struct sdhci_msm_pltfm_data *pdata;
>>>> +    u32 clk_rate;
>>>>  };
>>>>
>>>>  /* Platform specific tuning */
>>>> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct
>>>> sdhci_host *host)
>>>>      return msm_host->pdata->clk_table[0];
>>>>  }
>>>>
>>>> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
>>>> +                    u32 req_clk)
>>>> +{
>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>> +    int count = msm_host->pdata->clk_table_sz;
>>>> +    unsigned int sel_clk = -1;
>>>> +    int cnt;
>>>> +
>>>> +    if (req_clk < sdhci_msm_get_min_clock(host)) {
>>>> +        sel_clk = sdhci_msm_get_min_clock(host);
>>>> +        return sel_clk;
>>>> +    }
>>>> +
>>>> +    for (cnt = 0; cnt < count; cnt++) {
>>>> +        if (msm_host->pdata->clk_table[cnt] > req_clk) {
>>>> +            break;
>>>> +        } else if (msm_host->pdata->clk_table[cnt] == req_clk) {
>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>> +            break;
>>>> +        } else {
>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>> +        }
>>>> +    }
>>>
>>> 'else' is not needed after 'break' but can't this be simpler e.g.
>>>
>>> static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host
>>> *msm_host, u32 req_clk)
>>> {
>>>     int count = msm_host->pdata->clk_table_sz;
>>>     unsigned int sel_clk = -1;
>>>
>>>     while (count--) {
>>>         sel_clk = msm_host->pdata->clk_table[count];
>>>         if (req_clk >= sel_clk)
>>>             return sel_clk;
>>>     }
>>>
>>>     return sel_clk;
>>> }
>>
>> Ok, sure I will check and get back on this.
>>
>>
>>>
>>>
>>>> +    return sel_clk;
>>>> +}
>>>
>>> Blank line needed
>> Ok done.
>>
>>>
>>>> +/**
>>>> + * __sdhci_msm_set_clock - sdhci_msm clock control.
>>>> + *
>>>> + * Description:
>>>> + * Implement MSM version of sdhci_set_clock.
>>>> + * This is required since MSM controller does not
>>>> + * use internal divider and instead directly control
>>>> + * the GCC clock as per HW recommendation.
>>>> + **/
>>>> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>>>> +{
>>>> +    u16 clk;
>>>> +    unsigned long timeout;
>>>> +
>>>> +    host->mmc->actual_clock = 0;
>>>> +
>>>> +    sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
>>>> +
>>>> +    if (clock == 0)
>>>> +        return;
>>>
>>> Should set host->mmc->actual_clock to the actual rate somewhere.
>> Since MSM controller does not uses divider then there is no need of having
>> actual clock since it should be same as host->clock.
>
> Ok, so sdhci_msm_get_msm_clk_rate() is not the actual clock rate?
So I was assuming we need host->mmc->actual_clock rate if host->clock is 
not the actual rate.
Ok, so I will update actual_clock to host->clock itself.

pls, let me know if any concerns.
>
>>
>> That's why I had kept it 0 intentionally. But I will add a comment
>> here then.
>>
>>>
>>>> +
>>>> +    /*
>>>> +     * MSM controller do not use clock divider.
>>>> +     * Thus read SDHCI_CLOCK_CONTROL and only enable
>>>> +     * clock with no divider value programmed.
>>>> +     */
>>>> +    clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>>> +
>>>> +    clk |= SDHCI_CLOCK_INT_EN;
>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>> +
>>>> +    /* Wait max 20 ms */
>>>> +    timeout = 20;
>>>> +    while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
>>>> +        & SDHCI_CLOCK_INT_STABLE)) {
>>>> +        if (timeout == 0) {
>>>> +            pr_err("%s: Internal clock never stabilised.\n",
>>>> +                   mmc_hostname(host->mmc));
>>>> +            return;
>>>> +        }
>>>> +        timeout--;
>>>> +        mdelay(1);
>>>> +    }
>>>> +
>>>> +    clk |= SDHCI_CLOCK_CARD_EN;
>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>> +}
>>>> +
>>>> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int
>>>> clock)
>>>> +{
>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>> +    u32 msm_clock = 0;
>>>> +    int rc = 0;
>>>> +
>>>> +    if (!clock)
>>>> +        goto out;
>>>> +
>>>> +    if (clock != msm_host->clk_rate) {
>>>> +        msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>>>> +        rc = clk_set_rate(msm_host->clk, msm_clock);
>>>> +        if (rc) {
>>>> +            pr_err("%s: failed to set clock at rate %u, requested clock
>>>> rate %u\n",
>>>> +                mmc_hostname(host->mmc), msm_clock, clock);
>>>> +            goto out;
>>>> +        }
>>>> +        msm_host->clk_rate = clock;
>>>> +        pr_debug("%s: setting clock at rate %lu\n",
>>>> +            mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
>>>> +    }
>>>> +out:
>>>> +    __sdhci_msm_set_clock(host, clock);
>>>> +}
>>>> +
>>>>  static const struct of_device_id sdhci_msm_dt_match[] = {
>>>>      { .compatible = "qcom,sdhci-msm-v4" },
>>>>      {},
>>>> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>>>>  static const struct sdhci_ops sdhci_msm_ops = {
>>>>      .platform_execute_tuning = sdhci_msm_execute_tuning,
>>>>      .reset = sdhci_reset,
>>>> -    .set_clock = sdhci_set_clock,
>>>> +    .set_clock = sdhci_msm_set_clock,
>>>>      .get_min_clock = sdhci_msm_get_min_clock,
>>>>      .get_max_clock = sdhci_msm_get_max_clock,
>>>>      .set_bus_width = sdhci_set_bus_width,
>>>>
>>>
>>
>
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Adrian Hunter Aug. 22, 2016, 9:29 a.m. UTC | #5
On 22/08/16 12:07, Ritesh Harjani wrote:
> Hi Adrian,
> 
> 
> On 8/22/2016 11:50 AM, Adrian Hunter wrote:
>> On 19/08/16 16:31, Ritesh Harjani wrote:
>>> Hi,
>>>
>>>
>>> On 8/19/2016 6:34 PM, Adrian Hunter wrote:
>>>> On 19/08/16 07:36, Ritesh Harjani wrote:
>>>>> sdhci-msm controller may have different clk-rates for each
>>>>> bus speed mode. Thus implement set_clock callback for
>>>>> sdhci-msm driver.
>>>>>
>>>>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
>>>>> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
>>>>> ---
>>>>>  drivers/mmc/host/sdhci-msm.c | 103
>>>>> ++++++++++++++++++++++++++++++++++++++++++-
>>>>>  1 file changed, 102 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>>>>> index 7c032c3..c0ad9c2 100644
>>>>> --- a/drivers/mmc/host/sdhci-msm.c
>>>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>>>> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>>>>>      struct mmc_host *mmc;
>>>>>      bool use_14lpp_dll_reset;
>>>>>      struct sdhci_msm_pltfm_data *pdata;
>>>>> +    u32 clk_rate;
>>>>>  };
>>>>>
>>>>>  /* Platform specific tuning */
>>>>> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct
>>>>> sdhci_host *host)
>>>>>      return msm_host->pdata->clk_table[0];
>>>>>  }
>>>>>
>>>>> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
>>>>> +                    u32 req_clk)
>>>>> +{
>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>> +    int count = msm_host->pdata->clk_table_sz;
>>>>> +    unsigned int sel_clk = -1;
>>>>> +    int cnt;
>>>>> +
>>>>> +    if (req_clk < sdhci_msm_get_min_clock(host)) {
>>>>> +        sel_clk = sdhci_msm_get_min_clock(host);
>>>>> +        return sel_clk;
>>>>> +    }
>>>>> +
>>>>> +    for (cnt = 0; cnt < count; cnt++) {
>>>>> +        if (msm_host->pdata->clk_table[cnt] > req_clk) {
>>>>> +            break;
>>>>> +        } else if (msm_host->pdata->clk_table[cnt] == req_clk) {
>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>> +            break;
>>>>> +        } else {
>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>> +        }
>>>>> +    }
>>>>
>>>> 'else' is not needed after 'break' but can't this be simpler e.g.
>>>>
>>>> static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host
>>>> *msm_host, u32 req_clk)
>>>> {
>>>>     int count = msm_host->pdata->clk_table_sz;
>>>>     unsigned int sel_clk = -1;
>>>>
>>>>     while (count--) {
>>>>         sel_clk = msm_host->pdata->clk_table[count];
>>>>         if (req_clk >= sel_clk)
>>>>             return sel_clk;
>>>>     }
>>>>
>>>>     return sel_clk;
>>>> }
>>>
>>> Ok, sure I will check and get back on this.
>>>
>>>
>>>>
>>>>
>>>>> +    return sel_clk;
>>>>> +}
>>>>
>>>> Blank line needed
>>> Ok done.
>>>
>>>>
>>>>> +/**
>>>>> + * __sdhci_msm_set_clock - sdhci_msm clock control.
>>>>> + *
>>>>> + * Description:
>>>>> + * Implement MSM version of sdhci_set_clock.
>>>>> + * This is required since MSM controller does not
>>>>> + * use internal divider and instead directly control
>>>>> + * the GCC clock as per HW recommendation.
>>>>> + **/
>>>>> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>>>>> +{
>>>>> +    u16 clk;
>>>>> +    unsigned long timeout;
>>>>> +
>>>>> +    host->mmc->actual_clock = 0;
>>>>> +
>>>>> +    sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
>>>>> +
>>>>> +    if (clock == 0)
>>>>> +        return;
>>>>
>>>> Should set host->mmc->actual_clock to the actual rate somewhere.
>>> Since MSM controller does not uses divider then there is no need of having
>>> actual clock since it should be same as host->clock.
>>
>> Ok, so sdhci_msm_get_msm_clk_rate() is not the actual clock rate?
> So I was assuming we need host->mmc->actual_clock rate if host->clock is not
> the actual rate.
> Ok, so I will update actual_clock to host->clock itself.
> 
> pls, let me know if any concerns.

I am confused.  Isn't clk_get_rate(msm_host->clk) the actual clock rate?

>>
>>>
>>> That's why I had kept it 0 intentionally. But I will add a comment
>>> here then.
>>>
>>>>
>>>>> +
>>>>> +    /*
>>>>> +     * MSM controller do not use clock divider.
>>>>> +     * Thus read SDHCI_CLOCK_CONTROL and only enable
>>>>> +     * clock with no divider value programmed.
>>>>> +     */
>>>>> +    clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>>>> +
>>>>> +    clk |= SDHCI_CLOCK_INT_EN;
>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>> +
>>>>> +    /* Wait max 20 ms */
>>>>> +    timeout = 20;
>>>>> +    while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
>>>>> +        & SDHCI_CLOCK_INT_STABLE)) {
>>>>> +        if (timeout == 0) {
>>>>> +            pr_err("%s: Internal clock never stabilised.\n",
>>>>> +                   mmc_hostname(host->mmc));
>>>>> +            return;
>>>>> +        }
>>>>> +        timeout--;
>>>>> +        mdelay(1);
>>>>> +    }
>>>>> +
>>>>> +    clk |= SDHCI_CLOCK_CARD_EN;
>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>> +}
>>>>> +
>>>>> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int
>>>>> clock)
>>>>> +{
>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>> +    u32 msm_clock = 0;
>>>>> +    int rc = 0;
>>>>> +
>>>>> +    if (!clock)
>>>>> +        goto out;
>>>>> +
>>>>> +    if (clock != msm_host->clk_rate) {
>>>>> +        msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>>>>> +        rc = clk_set_rate(msm_host->clk, msm_clock);
>>>>> +        if (rc) {
>>>>> +            pr_err("%s: failed to set clock at rate %u, requested clock
>>>>> rate %u\n",
>>>>> +                mmc_hostname(host->mmc), msm_clock, clock);
>>>>> +            goto out;
>>>>> +        }
>>>>> +        msm_host->clk_rate = clock;
>>>>> +        pr_debug("%s: setting clock at rate %lu\n",
>>>>> +            mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
>>>>> +    }
>>>>> +out:
>>>>> +    __sdhci_msm_set_clock(host, clock);
>>>>> +}
>>>>> +
>>>>>  static const struct of_device_id sdhci_msm_dt_match[] = {
>>>>>      { .compatible = "qcom,sdhci-msm-v4" },
>>>>>      {},
>>>>> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>>>>>  static const struct sdhci_ops sdhci_msm_ops = {
>>>>>      .platform_execute_tuning = sdhci_msm_execute_tuning,
>>>>>      .reset = sdhci_reset,
>>>>> -    .set_clock = sdhci_set_clock,
>>>>> +    .set_clock = sdhci_msm_set_clock,
>>>>>      .get_min_clock = sdhci_msm_get_min_clock,
>>>>>      .get_max_clock = sdhci_msm_get_max_clock,
>>>>>      .set_bus_width = sdhci_set_bus_width,
>>>>>
>>>>
>>>
>>
> 

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Ritesh Harjani Aug. 22, 2016, 12:56 p.m. UTC | #6
Hi Adrian,


On 8/22/2016 2:59 PM, Adrian Hunter wrote:
> On 22/08/16 12:07, Ritesh Harjani wrote:
>> Hi Adrian,
>>
>>
>> On 8/22/2016 11:50 AM, Adrian Hunter wrote:
>>> On 19/08/16 16:31, Ritesh Harjani wrote:
>>>> Hi,
>>>>
>>>>
>>>> On 8/19/2016 6:34 PM, Adrian Hunter wrote:
>>>>> On 19/08/16 07:36, Ritesh Harjani wrote:
>>>>>> sdhci-msm controller may have different clk-rates for each
>>>>>> bus speed mode. Thus implement set_clock callback for
>>>>>> sdhci-msm driver.
>>>>>>
>>>>>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
>>>>>> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
>>>>>> ---
>>>>>>  drivers/mmc/host/sdhci-msm.c | 103
>>>>>> ++++++++++++++++++++++++++++++++++++++++++-
>>>>>>  1 file changed, 102 insertions(+), 1 deletion(-)
>>>>>>
>>>>>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>>>>>> index 7c032c3..c0ad9c2 100644
>>>>>> --- a/drivers/mmc/host/sdhci-msm.c
>>>>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>>>>> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>>>>>>      struct mmc_host *mmc;
>>>>>>      bool use_14lpp_dll_reset;
>>>>>>      struct sdhci_msm_pltfm_data *pdata;
>>>>>> +    u32 clk_rate;
>>>>>>  };
>>>>>>
>>>>>>  /* Platform specific tuning */
>>>>>> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct
>>>>>> sdhci_host *host)
>>>>>>      return msm_host->pdata->clk_table[0];
>>>>>>  }
>>>>>>
>>>>>> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
>>>>>> +                    u32 req_clk)
>>>>>> +{
>>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>>> +    int count = msm_host->pdata->clk_table_sz;
>>>>>> +    unsigned int sel_clk = -1;
>>>>>> +    int cnt;
>>>>>> +
>>>>>> +    if (req_clk < sdhci_msm_get_min_clock(host)) {
>>>>>> +        sel_clk = sdhci_msm_get_min_clock(host);
>>>>>> +        return sel_clk;
>>>>>> +    }
>>>>>> +
>>>>>> +    for (cnt = 0; cnt < count; cnt++) {
>>>>>> +        if (msm_host->pdata->clk_table[cnt] > req_clk) {
>>>>>> +            break;
>>>>>> +        } else if (msm_host->pdata->clk_table[cnt] == req_clk) {
>>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>>> +            break;
>>>>>> +        } else {
>>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>>> +        }
>>>>>> +    }
>>>>>
>>>>> 'else' is not needed after 'break' but can't this be simpler e.g.
>>>>>
>>>>> static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host
>>>>> *msm_host, u32 req_clk)
>>>>> {
>>>>>     int count = msm_host->pdata->clk_table_sz;
>>>>>     unsigned int sel_clk = -1;
>>>>>
>>>>>     while (count--) {
>>>>>         sel_clk = msm_host->pdata->clk_table[count];
>>>>>         if (req_clk >= sel_clk)
>>>>>             return sel_clk;
>>>>>     }
>>>>>
>>>>>     return sel_clk;
>>>>> }
>>>>
>>>> Ok, sure I will check and get back on this.
>>>>
>>>>
>>>>>
>>>>>
>>>>>> +    return sel_clk;
>>>>>> +}
>>>>>
>>>>> Blank line needed
>>>> Ok done.
>>>>
>>>>>
>>>>>> +/**
>>>>>> + * __sdhci_msm_set_clock - sdhci_msm clock control.
>>>>>> + *
>>>>>> + * Description:
>>>>>> + * Implement MSM version of sdhci_set_clock.
>>>>>> + * This is required since MSM controller does not
>>>>>> + * use internal divider and instead directly control
>>>>>> + * the GCC clock as per HW recommendation.
>>>>>> + **/
>>>>>> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>>>>>> +{
>>>>>> +    u16 clk;
>>>>>> +    unsigned long timeout;
>>>>>> +
>>>>>> +    host->mmc->actual_clock = 0;
>>>>>> +
>>>>>> +    sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
>>>>>> +
>>>>>> +    if (clock == 0)
>>>>>> +        return;
>>>>>
>>>>> Should set host->mmc->actual_clock to the actual rate somewhere.
>>>> Since MSM controller does not uses divider then there is no need of having
>>>> actual clock since it should be same as host->clock.
>>>
>>> Ok, so sdhci_msm_get_msm_clk_rate() is not the actual clock rate?
>> So I was assuming we need host->mmc->actual_clock rate if host->clock is not
>> the actual rate.
>> Ok, so I will update actual_clock to host->clock itself.
>>
>> pls, let me know if any concerns.
>
> I am confused.  Isn't clk_get_rate(msm_host->clk) the actual clock rate?

Actually, msm controller have few quirks around clocks itself and
I was thinking of not using actual_clock to avoid adding any extra 
quirks for msm.

If you see if actual_clock is 0 and if 
SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK is set, timeout_clk take host->clock 
for timeout calculation.

That's one reason I did not want to update the host->actual_clock. 
(otherwise timeout calc will go wrong for DDR modes for msm, where clock 
from GCC is made double of host->clock and internally divided by 
controller on it's own. In this case actual_clock would be shown as 2x 
of host->clock).
Do you think that keeping actual_clock to 0 should be fine in this case?


I have not yet worked over timeout calculation patches yet, since it is 
of lower priority in my list. After few other areas (mostly HS400), I 
will take over clock timeout fixes to be up-streamed.

>
>>>
>>>>
>>>> That's why I had kept it 0 intentionally. But I will add a comment
>>>> here then.
>>>>
>>>>>
>>>>>> +
>>>>>> +    /*
>>>>>> +     * MSM controller do not use clock divider.
>>>>>> +     * Thus read SDHCI_CLOCK_CONTROL and only enable
>>>>>> +     * clock with no divider value programmed.
>>>>>> +     */
>>>>>> +    clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>>>>> +
>>>>>> +    clk |= SDHCI_CLOCK_INT_EN;
>>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>>> +
>>>>>> +    /* Wait max 20 ms */
>>>>>> +    timeout = 20;
>>>>>> +    while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
>>>>>> +        & SDHCI_CLOCK_INT_STABLE)) {
>>>>>> +        if (timeout == 0) {
>>>>>> +            pr_err("%s: Internal clock never stabilised.\n",
>>>>>> +                   mmc_hostname(host->mmc));
>>>>>> +            return;
>>>>>> +        }
>>>>>> +        timeout--;
>>>>>> +        mdelay(1);
>>>>>> +    }
>>>>>> +
>>>>>> +    clk |= SDHCI_CLOCK_CARD_EN;
>>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>>> +}
>>>>>> +
>>>>>> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int
>>>>>> clock)
>>>>>> +{
>>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>>> +    u32 msm_clock = 0;
>>>>>> +    int rc = 0;
>>>>>> +
>>>>>> +    if (!clock)
>>>>>> +        goto out;
>>>>>> +
>>>>>> +    if (clock != msm_host->clk_rate) {
>>>>>> +        msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>>>>>> +        rc = clk_set_rate(msm_host->clk, msm_clock);
>>>>>> +        if (rc) {
>>>>>> +            pr_err("%s: failed to set clock at rate %u, requested clock
>>>>>> rate %u\n",
>>>>>> +                mmc_hostname(host->mmc), msm_clock, clock);
>>>>>> +            goto out;
>>>>>> +        }
>>>>>> +        msm_host->clk_rate = clock;
>>>>>> +        pr_debug("%s: setting clock at rate %lu\n",
>>>>>> +            mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
>>>>>> +    }
>>>>>> +out:
>>>>>> +    __sdhci_msm_set_clock(host, clock);
>>>>>> +}
>>>>>> +
>>>>>>  static const struct of_device_id sdhci_msm_dt_match[] = {
>>>>>>      { .compatible = "qcom,sdhci-msm-v4" },
>>>>>>      {},
>>>>>> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>>>>>>  static const struct sdhci_ops sdhci_msm_ops = {
>>>>>>      .platform_execute_tuning = sdhci_msm_execute_tuning,
>>>>>>      .reset = sdhci_reset,
>>>>>> -    .set_clock = sdhci_set_clock,
>>>>>> +    .set_clock = sdhci_msm_set_clock,
>>>>>>      .get_min_clock = sdhci_msm_get_min_clock,
>>>>>>      .get_max_clock = sdhci_msm_get_max_clock,
>>>>>>      .set_bus_width = sdhci_set_bus_width,
>>>>>>
>>>>>
>>>>
>>>
>>
>
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Adrian Hunter Aug. 23, 2016, 1:17 p.m. UTC | #7
On 22/08/16 15:56, Ritesh Harjani wrote:
> Hi Adrian,
> 
> 
> On 8/22/2016 2:59 PM, Adrian Hunter wrote:
>> On 22/08/16 12:07, Ritesh Harjani wrote:
>>> Hi Adrian,
>>>
>>>
>>> On 8/22/2016 11:50 AM, Adrian Hunter wrote:
>>>> On 19/08/16 16:31, Ritesh Harjani wrote:
>>>>> Hi,
>>>>>
>>>>>
>>>>> On 8/19/2016 6:34 PM, Adrian Hunter wrote:
>>>>>> On 19/08/16 07:36, Ritesh Harjani wrote:
>>>>>>> sdhci-msm controller may have different clk-rates for each
>>>>>>> bus speed mode. Thus implement set_clock callback for
>>>>>>> sdhci-msm driver.
>>>>>>>
>>>>>>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
>>>>>>> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
>>>>>>> ---
>>>>>>>  drivers/mmc/host/sdhci-msm.c | 103
>>>>>>> ++++++++++++++++++++++++++++++++++++++++++-
>>>>>>>  1 file changed, 102 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>>>>>>> index 7c032c3..c0ad9c2 100644
>>>>>>> --- a/drivers/mmc/host/sdhci-msm.c
>>>>>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>>>>>> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>>>>>>>      struct mmc_host *mmc;
>>>>>>>      bool use_14lpp_dll_reset;
>>>>>>>      struct sdhci_msm_pltfm_data *pdata;
>>>>>>> +    u32 clk_rate;
>>>>>>>  };
>>>>>>>
>>>>>>>  /* Platform specific tuning */
>>>>>>> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct
>>>>>>> sdhci_host *host)
>>>>>>>      return msm_host->pdata->clk_table[0];
>>>>>>>  }
>>>>>>>
>>>>>>> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
>>>>>>> +                    u32 req_clk)
>>>>>>> +{
>>>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>>>> +    int count = msm_host->pdata->clk_table_sz;
>>>>>>> +    unsigned int sel_clk = -1;
>>>>>>> +    int cnt;
>>>>>>> +
>>>>>>> +    if (req_clk < sdhci_msm_get_min_clock(host)) {
>>>>>>> +        sel_clk = sdhci_msm_get_min_clock(host);
>>>>>>> +        return sel_clk;
>>>>>>> +    }
>>>>>>> +
>>>>>>> +    for (cnt = 0; cnt < count; cnt++) {
>>>>>>> +        if (msm_host->pdata->clk_table[cnt] > req_clk) {
>>>>>>> +            break;
>>>>>>> +        } else if (msm_host->pdata->clk_table[cnt] == req_clk) {
>>>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>>>> +            break;
>>>>>>> +        } else {
>>>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>>>> +        }
>>>>>>> +    }
>>>>>>
>>>>>> 'else' is not needed after 'break' but can't this be simpler e.g.
>>>>>>
>>>>>> static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host
>>>>>> *msm_host, u32 req_clk)
>>>>>> {
>>>>>>     int count = msm_host->pdata->clk_table_sz;
>>>>>>     unsigned int sel_clk = -1;
>>>>>>
>>>>>>     while (count--) {
>>>>>>         sel_clk = msm_host->pdata->clk_table[count];
>>>>>>         if (req_clk >= sel_clk)
>>>>>>             return sel_clk;
>>>>>>     }
>>>>>>
>>>>>>     return sel_clk;
>>>>>> }
>>>>>
>>>>> Ok, sure I will check and get back on this.
>>>>>
>>>>>
>>>>>>
>>>>>>
>>>>>>> +    return sel_clk;
>>>>>>> +}
>>>>>>
>>>>>> Blank line needed
>>>>> Ok done.
>>>>>
>>>>>>
>>>>>>> +/**
>>>>>>> + * __sdhci_msm_set_clock - sdhci_msm clock control.
>>>>>>> + *
>>>>>>> + * Description:
>>>>>>> + * Implement MSM version of sdhci_set_clock.
>>>>>>> + * This is required since MSM controller does not
>>>>>>> + * use internal divider and instead directly control
>>>>>>> + * the GCC clock as per HW recommendation.
>>>>>>> + **/
>>>>>>> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>>>>>>> +{
>>>>>>> +    u16 clk;
>>>>>>> +    unsigned long timeout;
>>>>>>> +
>>>>>>> +    host->mmc->actual_clock = 0;
>>>>>>> +
>>>>>>> +    sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
>>>>>>> +
>>>>>>> +    if (clock == 0)
>>>>>>> +        return;
>>>>>>
>>>>>> Should set host->mmc->actual_clock to the actual rate somewhere.
>>>>> Since MSM controller does not uses divider then there is no need of having
>>>>> actual clock since it should be same as host->clock.
>>>>
>>>> Ok, so sdhci_msm_get_msm_clk_rate() is not the actual clock rate?
>>> So I was assuming we need host->mmc->actual_clock rate if host->clock is not
>>> the actual rate.
>>> Ok, so I will update actual_clock to host->clock itself.
>>>
>>> pls, let me know if any concerns.
>>
>> I am confused.  Isn't clk_get_rate(msm_host->clk) the actual clock rate?
> 
> Actually, msm controller have few quirks around clocks itself and
> I was thinking of not using actual_clock to avoid adding any extra quirks
> for msm.
> 
> If you see if actual_clock is 0 and if SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK
> is set, timeout_clk take host->clock for timeout calculation.
> 
> That's one reason I did not want to update the host->actual_clock.
> (otherwise timeout calc will go wrong for DDR modes for msm, where clock
> from GCC is made double of host->clock and internally divided by controller
> on it's own. In this case actual_clock would be shown as 2x of host->clock).
> Do you think that keeping actual_clock to 0 should be fine in this case?

Yes, but please add a comment in the code.

> 
> 
> I have not yet worked over timeout calculation patches yet, since it is of
> lower priority in my list. After few other areas (mostly HS400), I will take
> over clock timeout fixes to be up-streamed.
> 
>>
>>>>
>>>>>
>>>>> That's why I had kept it 0 intentionally. But I will add a comment
>>>>> here then.
>>>>>
>>>>>>
>>>>>>> +
>>>>>>> +    /*
>>>>>>> +     * MSM controller do not use clock divider.
>>>>>>> +     * Thus read SDHCI_CLOCK_CONTROL and only enable
>>>>>>> +     * clock with no divider value programmed.
>>>>>>> +     */
>>>>>>> +    clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>>>>>> +
>>>>>>> +    clk |= SDHCI_CLOCK_INT_EN;
>>>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>>>> +
>>>>>>> +    /* Wait max 20 ms */
>>>>>>> +    timeout = 20;
>>>>>>> +    while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
>>>>>>> +        & SDHCI_CLOCK_INT_STABLE)) {
>>>>>>> +        if (timeout == 0) {
>>>>>>> +            pr_err("%s: Internal clock never stabilised.\n",
>>>>>>> +                   mmc_hostname(host->mmc));
>>>>>>> +            return;
>>>>>>> +        }
>>>>>>> +        timeout--;
>>>>>>> +        mdelay(1);
>>>>>>> +    }
>>>>>>> +
>>>>>>> +    clk |= SDHCI_CLOCK_CARD_EN;
>>>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>>>> +}
>>>>>>> +
>>>>>>> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int
>>>>>>> clock)
>>>>>>> +{
>>>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>>>> +    u32 msm_clock = 0;
>>>>>>> +    int rc = 0;
>>>>>>> +
>>>>>>> +    if (!clock)
>>>>>>> +        goto out;
>>>>>>> +
>>>>>>> +    if (clock != msm_host->clk_rate) {
>>>>>>> +        msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>>>>>>> +        rc = clk_set_rate(msm_host->clk, msm_clock);
>>>>>>> +        if (rc) {
>>>>>>> +            pr_err("%s: failed to set clock at rate %u, requested clock
>>>>>>> rate %u\n",
>>>>>>> +                mmc_hostname(host->mmc), msm_clock, clock);
>>>>>>> +            goto out;
>>>>>>> +        }
>>>>>>> +        msm_host->clk_rate = clock;
>>>>>>> +        pr_debug("%s: setting clock at rate %lu\n",
>>>>>>> +            mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
>>>>>>> +    }
>>>>>>> +out:
>>>>>>> +    __sdhci_msm_set_clock(host, clock);
>>>>>>> +}
>>>>>>> +
>>>>>>>  static const struct of_device_id sdhci_msm_dt_match[] = {
>>>>>>>      { .compatible = "qcom,sdhci-msm-v4" },
>>>>>>>      {},
>>>>>>> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>>>>>>>  static const struct sdhci_ops sdhci_msm_ops = {
>>>>>>>      .platform_execute_tuning = sdhci_msm_execute_tuning,
>>>>>>>      .reset = sdhci_reset,
>>>>>>> -    .set_clock = sdhci_set_clock,
>>>>>>> +    .set_clock = sdhci_msm_set_clock,
>>>>>>>      .get_min_clock = sdhci_msm_get_min_clock,
>>>>>>>      .get_max_clock = sdhci_msm_get_max_clock,
>>>>>>>      .set_bus_width = sdhci_set_bus_width,
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
> 

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Ritesh Harjani Aug. 23, 2016, 1:39 p.m. UTC | #8
Hi,

On 8/23/2016 6:47 PM, Adrian Hunter wrote:
> On 22/08/16 15:56, Ritesh Harjani wrote:
>> Hi Adrian,
>>
>>
>> On 8/22/2016 2:59 PM, Adrian Hunter wrote:
>>> On 22/08/16 12:07, Ritesh Harjani wrote:
>>>> Hi Adrian,
>>>>
>>>>
>>>> On 8/22/2016 11:50 AM, Adrian Hunter wrote:
>>>>> On 19/08/16 16:31, Ritesh Harjani wrote:
>>>>>> Hi,
>>>>>>
>>>>>>
>>>>>> On 8/19/2016 6:34 PM, Adrian Hunter wrote:
>>>>>>> On 19/08/16 07:36, Ritesh Harjani wrote:
>>>>>>>> sdhci-msm controller may have different clk-rates for each
>>>>>>>> bus speed mode. Thus implement set_clock callback for
>>>>>>>> sdhci-msm driver.
>>>>>>>>
>>>>>>>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
>>>>>>>> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
>>>>>>>> ---
>>>>>>>>  drivers/mmc/host/sdhci-msm.c | 103
>>>>>>>> ++++++++++++++++++++++++++++++++++++++++++-
>>>>>>>>  1 file changed, 102 insertions(+), 1 deletion(-)
>>>>>>>>
>>>>>>>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>>>>>>>> index 7c032c3..c0ad9c2 100644
>>>>>>>> --- a/drivers/mmc/host/sdhci-msm.c
>>>>>>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>>>>>>> @@ -89,6 +89,7 @@ struct sdhci_msm_host {
>>>>>>>>      struct mmc_host *mmc;
>>>>>>>>      bool use_14lpp_dll_reset;
>>>>>>>>      struct sdhci_msm_pltfm_data *pdata;
>>>>>>>> +    u32 clk_rate;
>>>>>>>>  };
>>>>>>>>
>>>>>>>>  /* Platform specific tuning */
>>>>>>>> @@ -582,6 +583,106 @@ static unsigned int sdhci_msm_get_min_clock(struct
>>>>>>>> sdhci_host *host)
>>>>>>>>      return msm_host->pdata->clk_table[0];
>>>>>>>>  }
>>>>>>>>
>>>>>>>> +static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
>>>>>>>> +                    u32 req_clk)
>>>>>>>> +{
>>>>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>>>>> +    int count = msm_host->pdata->clk_table_sz;
>>>>>>>> +    unsigned int sel_clk = -1;
>>>>>>>> +    int cnt;
>>>>>>>> +
>>>>>>>> +    if (req_clk < sdhci_msm_get_min_clock(host)) {
>>>>>>>> +        sel_clk = sdhci_msm_get_min_clock(host);
>>>>>>>> +        return sel_clk;
>>>>>>>> +    }
>>>>>>>> +
>>>>>>>> +    for (cnt = 0; cnt < count; cnt++) {
>>>>>>>> +        if (msm_host->pdata->clk_table[cnt] > req_clk) {
>>>>>>>> +            break;
>>>>>>>> +        } else if (msm_host->pdata->clk_table[cnt] == req_clk) {
>>>>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>>>>> +            break;
>>>>>>>> +        } else {
>>>>>>>> +            sel_clk = msm_host->pdata->clk_table[cnt];
>>>>>>>> +        }
>>>>>>>> +    }
>>>>>>>
>>>>>>> 'else' is not needed after 'break' but can't this be simpler e.g.
>>>>>>>
>>>>>>> static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_msm_host
>>>>>>> *msm_host, u32 req_clk)
>>>>>>> {
>>>>>>>     int count = msm_host->pdata->clk_table_sz;
>>>>>>>     unsigned int sel_clk = -1;
>>>>>>>
>>>>>>>     while (count--) {
>>>>>>>         sel_clk = msm_host->pdata->clk_table[count];
>>>>>>>         if (req_clk >= sel_clk)
>>>>>>>             return sel_clk;
>>>>>>>     }
>>>>>>>
>>>>>>>     return sel_clk;
>>>>>>> }
>>>>>>
>>>>>> Ok, sure I will check and get back on this.
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> +    return sel_clk;
>>>>>>>> +}
>>>>>>>
>>>>>>> Blank line needed
>>>>>> Ok done.
>>>>>>
>>>>>>>
>>>>>>>> +/**
>>>>>>>> + * __sdhci_msm_set_clock - sdhci_msm clock control.
>>>>>>>> + *
>>>>>>>> + * Description:
>>>>>>>> + * Implement MSM version of sdhci_set_clock.
>>>>>>>> + * This is required since MSM controller does not
>>>>>>>> + * use internal divider and instead directly control
>>>>>>>> + * the GCC clock as per HW recommendation.
>>>>>>>> + **/
>>>>>>>> +void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>>>>>>>> +{
>>>>>>>> +    u16 clk;
>>>>>>>> +    unsigned long timeout;
>>>>>>>> +
>>>>>>>> +    host->mmc->actual_clock = 0;
>>>>>>>> +
>>>>>>>> +    sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
>>>>>>>> +
>>>>>>>> +    if (clock == 0)
>>>>>>>> +        return;
>>>>>>>
>>>>>>> Should set host->mmc->actual_clock to the actual rate somewhere.
>>>>>> Since MSM controller does not uses divider then there is no need of having
>>>>>> actual clock since it should be same as host->clock.
>>>>>
>>>>> Ok, so sdhci_msm_get_msm_clk_rate() is not the actual clock rate?
>>>> So I was assuming we need host->mmc->actual_clock rate if host->clock is not
>>>> the actual rate.
>>>> Ok, so I will update actual_clock to host->clock itself.
>>>>
>>>> pls, let me know if any concerns.
>>>
>>> I am confused.  Isn't clk_get_rate(msm_host->clk) the actual clock rate?
>>
>> Actually, msm controller have few quirks around clocks itself and
>> I was thinking of not using actual_clock to avoid adding any extra quirks
>> for msm.
>>
>> If you see if actual_clock is 0 and if SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK
>> is set, timeout_clk take host->clock for timeout calculation.
>>
>> That's one reason I did not want to update the host->actual_clock.
>> (otherwise timeout calc will go wrong for DDR modes for msm, where clock
>> from GCC is made double of host->clock and internally divided by controller
>> on it's own. In this case actual_clock would be shown as 2x of host->clock).
>> Do you think that keeping actual_clock to 0 should be fine in this case?
>
> Yes, but please add a comment in the code.

Sure thanks. I will address all comments in v4 spin.

>
>>
>>
>> I have not yet worked over timeout calculation patches yet, since it is of
>> lower priority in my list. After few other areas (mostly HS400), I will take
>> over clock timeout fixes to be up-streamed.
>>
>>>
>>>>>
>>>>>>
>>>>>> That's why I had kept it 0 intentionally. But I will add a comment
>>>>>> here then.
>>>>>>
>>>>>>>
>>>>>>>> +
>>>>>>>> +    /*
>>>>>>>> +     * MSM controller do not use clock divider.
>>>>>>>> +     * Thus read SDHCI_CLOCK_CONTROL and only enable
>>>>>>>> +     * clock with no divider value programmed.
>>>>>>>> +     */
>>>>>>>> +    clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>>>>>>> +
>>>>>>>> +    clk |= SDHCI_CLOCK_INT_EN;
>>>>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>>>>> +
>>>>>>>> +    /* Wait max 20 ms */
>>>>>>>> +    timeout = 20;
>>>>>>>> +    while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
>>>>>>>> +        & SDHCI_CLOCK_INT_STABLE)) {
>>>>>>>> +        if (timeout == 0) {
>>>>>>>> +            pr_err("%s: Internal clock never stabilised.\n",
>>>>>>>> +                   mmc_hostname(host->mmc));
>>>>>>>> +            return;
>>>>>>>> +        }
>>>>>>>> +        timeout--;
>>>>>>>> +        mdelay(1);
>>>>>>>> +    }
>>>>>>>> +
>>>>>>>> +    clk |= SDHCI_CLOCK_CARD_EN;
>>>>>>>> +    sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>>>>>>> +}
>>>>>>>> +
>>>>>>>> +static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int
>>>>>>>> clock)
>>>>>>>> +{
>>>>>>>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>>>>> +    struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>>>>>>>> +    u32 msm_clock = 0;
>>>>>>>> +    int rc = 0;
>>>>>>>> +
>>>>>>>> +    if (!clock)
>>>>>>>> +        goto out;
>>>>>>>> +
>>>>>>>> +    if (clock != msm_host->clk_rate) {
>>>>>>>> +        msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>>>>>>>> +        rc = clk_set_rate(msm_host->clk, msm_clock);
>>>>>>>> +        if (rc) {
>>>>>>>> +            pr_err("%s: failed to set clock at rate %u, requested clock
>>>>>>>> rate %u\n",
>>>>>>>> +                mmc_hostname(host->mmc), msm_clock, clock);
>>>>>>>> +            goto out;
>>>>>>>> +        }
>>>>>>>> +        msm_host->clk_rate = clock;
>>>>>>>> +        pr_debug("%s: setting clock at rate %lu\n",
>>>>>>>> +            mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
>>>>>>>> +    }
>>>>>>>> +out:
>>>>>>>> +    __sdhci_msm_set_clock(host, clock);
>>>>>>>> +}
>>>>>>>> +
>>>>>>>>  static const struct of_device_id sdhci_msm_dt_match[] = {
>>>>>>>>      { .compatible = "qcom,sdhci-msm-v4" },
>>>>>>>>      {},
>>>>>>>> @@ -592,7 +693,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>>>>>>>>  static const struct sdhci_ops sdhci_msm_ops = {
>>>>>>>>      .platform_execute_tuning = sdhci_msm_execute_tuning,
>>>>>>>>      .reset = sdhci_reset,
>>>>>>>> -    .set_clock = sdhci_set_clock,
>>>>>>>> +    .set_clock = sdhci_msm_set_clock,
>>>>>>>>      .get_min_clock = sdhci_msm_get_min_clock,
>>>>>>>>      .get_max_clock = sdhci_msm_get_max_clock,
>>>>>>>>      .set_bus_width = sdhci_set_bus_width,
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>
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diff mbox

Patch

diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index 7c032c3..c0ad9c2 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -89,6 +89,7 @@  struct sdhci_msm_host {
 	struct mmc_host *mmc;
 	bool use_14lpp_dll_reset;
 	struct sdhci_msm_pltfm_data *pdata;
+	u32 clk_rate;
 };
 
 /* Platform specific tuning */
@@ -582,6 +583,106 @@  static unsigned int sdhci_msm_get_min_clock(struct sdhci_host *host)
 	return msm_host->pdata->clk_table[0];
 }
 
+static unsigned int sdhci_msm_get_msm_clk_rate(struct sdhci_host *host,
+					u32 req_clk)
+{
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
+	int count = msm_host->pdata->clk_table_sz;
+	unsigned int sel_clk = -1;
+	int cnt;
+
+	if (req_clk < sdhci_msm_get_min_clock(host)) {
+		sel_clk = sdhci_msm_get_min_clock(host);
+		return sel_clk;
+	}
+
+	for (cnt = 0; cnt < count; cnt++) {
+		if (msm_host->pdata->clk_table[cnt] > req_clk) {
+			break;
+		} else if (msm_host->pdata->clk_table[cnt] == req_clk) {
+			sel_clk = msm_host->pdata->clk_table[cnt];
+			break;
+		} else {
+			sel_clk = msm_host->pdata->clk_table[cnt];
+		}
+	}
+	return sel_clk;
+}
+/**
+ * __sdhci_msm_set_clock - sdhci_msm clock control.
+ *
+ * Description:
+ * Implement MSM version of sdhci_set_clock.
+ * This is required since MSM controller does not
+ * use internal divider and instead directly control
+ * the GCC clock as per HW recommendation.
+ **/
+void __sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+	u16 clk;
+	unsigned long timeout;
+
+	host->mmc->actual_clock = 0;
+
+	sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+
+	if (clock == 0)
+		return;
+
+	/*
+	 * MSM controller do not use clock divider.
+	 * Thus read SDHCI_CLOCK_CONTROL and only enable
+	 * clock with no divider value programmed.
+	 */
+	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+
+	clk |= SDHCI_CLOCK_INT_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+	/* Wait max 20 ms */
+	timeout = 20;
+	while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
+		& SDHCI_CLOCK_INT_STABLE)) {
+		if (timeout == 0) {
+			pr_err("%s: Internal clock never stabilised.\n",
+			       mmc_hostname(host->mmc));
+			return;
+		}
+		timeout--;
+		mdelay(1);
+	}
+
+	clk |= SDHCI_CLOCK_CARD_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+}
+
+static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
+	u32 msm_clock = 0;
+	int rc = 0;
+
+	if (!clock)
+		goto out;
+
+	if (clock != msm_host->clk_rate) {
+		msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
+		rc = clk_set_rate(msm_host->clk, msm_clock);
+		if (rc) {
+			pr_err("%s: failed to set clock at rate %u, requested clock rate %u\n",
+				mmc_hostname(host->mmc), msm_clock, clock);
+			goto out;
+		}
+		msm_host->clk_rate = clock;
+		pr_debug("%s: setting clock at rate %lu\n",
+			mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
+	}
+out:
+	__sdhci_msm_set_clock(host, clock);
+}
+
 static const struct of_device_id sdhci_msm_dt_match[] = {
 	{ .compatible = "qcom,sdhci-msm-v4" },
 	{},
@@ -592,7 +693,7 @@  MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
 static const struct sdhci_ops sdhci_msm_ops = {
 	.platform_execute_tuning = sdhci_msm_execute_tuning,
 	.reset = sdhci_reset,
-	.set_clock = sdhci_set_clock,
+	.set_clock = sdhci_msm_set_clock,
 	.get_min_clock = sdhci_msm_get_min_clock,
 	.get_max_clock = sdhci_msm_get_max_clock,
 	.set_bus_width = sdhci_set_bus_width,