Re: [PATCH V4 4/8] drivers: mmc: am654_sdhci: Update OTAP/ITAP delay

[Nitin Yadav <n-yadav@ti.com>]

Hi Mattijs,

On 23/08/23 13:36, Mattijs Korpershoek wrote:
> On mar., août 22, 2023 at 13:41, Nishanth Menon <nm@ti.com> wrote:
> 
>> From: Nitin Yadav <n-yadav@ti.com>
>>
>> U-Boot is fail to boot class U1 UHS SD cards (such as microcenter)
>> due to incorrect OTAP and ITAP delay select values. Update OTAP and
>> ITAP delay select values based on recommeded RIOT values to fix boot
>> issue.
> 
> nitpick: recommeded -> recommended
> 
>>
>> Signed-off-by: Nitin Yadav <n-yadav@ti.com>
>> Signed-off-by: Nishanth Menon <nm@ti.com>
>> ---
>> Picked up from TI u-boot
>> New patch in the series
>>
>>   drivers/mmc/am654_sdhci.c | 14 ++++++++++----
>>   1 file changed, 10 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/mmc/am654_sdhci.c b/drivers/mmc/am654_sdhci.c
>> index fd667aeafdaa..d0b51c0707d4 100644
>> --- a/drivers/mmc/am654_sdhci.c
>> +++ b/drivers/mmc/am654_sdhci.c
>> @@ -442,12 +442,18 @@ static int j721e_4bit_sdhci_set_ios_post(struct sdhci_host *host)
>>   {
>>   	struct udevice *dev = host->mmc->dev;
>>   	struct am654_sdhci_plat *plat = dev_get_plat(dev);
>> -	u32 otap_del_sel, mask, val;
>> +	u32 otap_del_sel, itap_del_sel, mask, val;
>>   
>>   	otap_del_sel = plat->otap_del_sel[host->mmc->selected_mode];
>> -	mask = OTAPDLYENA_MASK | OTAPDLYSEL_MASK;
>> -	val = (1 << OTAPDLYENA_SHIFT) | (otap_del_sel << OTAPDLYSEL_SHIFT);
>> +	itap_del_sel = plat->itap_del_sel[host->mmc->selected_mode];
>> +	mask = OTAPDLYENA_MASK | OTAPDLYSEL_MASK | ITAPDLYSEL_MASK |
>> +		ITAPDLYENA_MASK;
>> +	val = (1 << OTAPDLYENA_SHIFT) | (otap_del_sel << OTAPDLYSEL_SHIFT) |
>> +		(1 << ITAPDLYENA_SHIFT) | (itap_del_sel << ITAPDLYSEL_SHIFT);
>> +	regmap_update_bits(plat->base, PHY_CTRL4, ITAPCHGWIN_MASK,
>> +			   1 << ITAPCHGWIN_SHIFT);
>>   	regmap_update_bits(plat->base, PHY_CTRL4, mask, val);
>> +	regmap_update_bits(plat->base, PHY_CTRL4, ITAPCHGWIN_MASK, 0);
>>   
>>   	regmap_update_bits(plat->base, PHY_CTRL5, CLKBUFSEL_MASK,
>>   			   plat->clkbuf_sel);
>> @@ -501,7 +507,7 @@ static int sdhci_am654_get_otap_delay(struct udevice *dev,
>>   	 * Remove the corresponding capability if an otap-del-sel
>>   	 * value is not found
>>   	 */
>> -	for (i = MMC_HS; i <= MMC_HS_400; i++) {
>> +	for (i = MMC_LEGACY; i <= MMC_HS_400; i++) {
> 
> I'm not super familiar with mmc drivers in general, but it feels like
> this bit does not really belong in this patch. >
> Is this another bugfix for removing otap-del-sel for MMC_LEGACY devices
> or does U1 UHS SD cards are considered to be of MMC_LEGACY type ?
yes, its two different fix. Internally I posted two patches for them. 
can be referred in below links:

https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/?h=ti-linux-6.1.y-cicd&id=b5a2f7972fd142df03a15ba58829aa068c891abf

https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/?h=ti-linux-6.1.y-cicd&id=527095165281cbc60a1b42995c1e55e6756cbe93

> 
>>   		ret = dev_read_u32(dev, td[i].otap_binding,
>>   				   &plat->otap_del_sel[i]);
>>   		if (ret) {
>> -- 
>> 2.40.0

-- 
Regards,
Nitin