On 12/10/16 15:17, Ziji Hu wrote:
> Hi Adrian,
>
> On 2016/10/11 20:39, Adrian Hunter wrote:
>> On 07/10/16 18:22, Gregory CLEMENT wrote:
>>> From: Ziji Hu <huziji@xxxxxxxxxxx>
>>>
>>> Marvell Xenon eMMC/SD/SDIO Host Controller contains PHY.
>>> Three types of PHYs are supported.
>>>
>>> Add support to multiple types of PHYs init and configuration.
>>> Add register definitions of PHYs.
>>>
>>> Signed-off-by: Hu Ziji <huziji@xxxxxxxxxxx>
>>> Reviewed-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
>>> Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
>>> ---
>>> MAINTAINERS | 1 +-
>>> drivers/mmc/host/Makefile | 2 +-
>>> drivers/mmc/host/sdhci-xenon-phy.c | 1141 +++++++++++++++++++++++++++++-
>>> drivers/mmc/host/sdhci-xenon-phy.h | 157 ++++-
>>> drivers/mmc/host/sdhci-xenon.c | 4 +-
>>> drivers/mmc/host/sdhci-xenon.h | 17 +-
>>> 6 files changed, 1321 insertions(+), 1 deletion(-)
>>> create mode 100644 drivers/mmc/host/sdhci-xenon-phy.c
>>> create mode 100644 drivers/mmc/host/sdhci-xenon-phy.h
>>>
>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>> index 859420e5dfd3..b5673c2ee5f2 100644
>>> --- a/MAINTAINERS
>>> +++ b/MAINTAINERS
>>> @@ -7583,6 +7583,7 @@ M: Ziji Hu <huziji@xxxxxxxxxxx>
>>> L: linux-mmc@xxxxxxxxxxxxxxx
>>> S: Supported
>>> F: drivers/mmc/host/sdhci-xenon.*
>>> +F: drivers/mmc/host/sdhci-xenon-phy.*
>>> F: Documentation/devicetree/bindings/mmc/marvell,sdhci-xenon.txt
>>>
>>> MATROX FRAMEBUFFER DRIVER
>>> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
>>> index 75eaf743486c..4f2854556ff7 100644
>>> --- a/drivers/mmc/host/Makefile
>>> +++ b/drivers/mmc/host/Makefile
>>> @@ -82,4 +82,4 @@ ifeq ($(CONFIG_CB710_DEBUG),y)
>>> endif
>>>
>>> obj-$(CONFIG_MMC_SDHCI_XENON) += sdhci-xenon-driver.o
>>> -sdhci-xenon-driver-y += sdhci-xenon.o
>>> +sdhci-xenon-driver-y += sdhci-xenon.o sdhci-xenon-phy.o
>>> diff --git a/drivers/mmc/host/sdhci-xenon-phy.c b/drivers/mmc/host/sdhci-xenon-phy.c
>>> new file mode 100644
>>> index 000000000000..4eb8fea1bec9
>>> --- /dev/null
>>> +++ b/drivers/mmc/host/sdhci-xenon-phy.c
>>
>> <SNIP>
>>
>>> +static int __xenon_emmc_delay_adj_test(struct mmc_card *card)
>>> +{
>>> + int err;
>>> + u8 *ext_csd = NULL;
>>> +
>>> + err = mmc_get_ext_csd(card, &ext_csd);
>>> + kfree(ext_csd);
>>> +
>>> + return err;
>>> +}
>>> +
>>> +static int __xenon_sdio_delay_adj_test(struct mmc_card *card)
>>> +{
>>> + struct mmc_command cmd = {0};
>>> + int err;
>>> +
>>> + cmd.opcode = SD_IO_RW_DIRECT;
>>> + cmd.flags = MMC_RSP_R5 | MMC_CMD_AC;
>>> +
>>> + err = mmc_wait_for_cmd(card->host, &cmd, 0);
>>> + if (err)
>>> + return err;
>>> +
>>> + if (cmd.resp[0] & R5_ERROR)
>>> + return -EIO;
>>> + if (cmd.resp[0] & R5_FUNCTION_NUMBER)
>>> + return -EINVAL;
>>> + if (cmd.resp[0] & R5_OUT_OF_RANGE)
>>> + return -ERANGE;
>>> + return 0;
>>> +}
>>> +
>>> +static int __xenon_sd_delay_adj_test(struct mmc_card *card)
>>> +{
>>> + struct mmc_command cmd = {0};
>>> + int err;
>>> +
>>> + cmd.opcode = MMC_SEND_STATUS;
>>> + cmd.arg = card->rca << 16;
>>> + cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
>>> +
>>> + err = mmc_wait_for_cmd(card->host, &cmd, 0);
>>> + return err;
>>> +}
>>> +
>>> +static int xenon_delay_adj_test(struct mmc_card *card)
>>> +{
>>> + WARN_ON(!card);
>>> + WARN_ON(!card->host);
>>> +
>>> + if (mmc_card_mmc(card))
>>> + return __xenon_emmc_delay_adj_test(card);
>>> + else if (mmc_card_sd(card))
>>> + return __xenon_sd_delay_adj_test(card);
>>> + else if (mmc_card_sdio(card))
>>> + return __xenon_sdio_delay_adj_test(card);
>>> + else
>>> + return -EINVAL;
>>> +}
>>
>> So you are issuing commands from the ->set_ios() callback. I would want to
>> get Ulf's OK for that before going further.
>>
> Yes, you are correct.
> In some speed mode, Xenon SDHC has to send a series of transfers to search for a perfect sampling point in PHY delay line.
> It is like tuning process.
>
>> One thing: you will need to ensure you don't trigger get HS400 re-tuning
>> because it will call back into ->set_ios().
>>
> Could you please make the term "HS400 re-tuning" more detailed?
> In current MMC driver, "HS400 re-tuning" will go back to HS200, execute HS200 tuning and come back to HS400.
> I'm sure our Xenon SDHC will not execute it.
Currently, re-tuning is automatically enabled whenever tuning is executed,
and then re-tuning will be done periodically or after CRC errors. The
function to disable re-tuning mmc_retune_disable() is not exported, however
if you have you are determining the sampling point your own way, you could
simply not implement ->execute_tuning() and then there would be no tuning
and no re-tuning.
>
> However, in coming eMMC 5.2, there is a real HS400 re-tuning, in which tuning can be directly executed in HS400 mode.
> Our Xenon SDHC will neither trigger this HS400 re-tuning.
> But since so far there is no such feature in MMC driver, I cannot give you a 100% guarantee now.
>
>> And you have the problem that you need to get a reference to the card before
>> the card device has been added. As I wrote in response to the previous
>> patch, you should get Ulf's help with that too.
>>
> Sure.
> I will get card_candidate solved at first.
> Thank you again for your review and help.
>
> Thank you.
>
> Best regards,
> Hu Ziji
>>
>
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
