On 10/09/24 17:30, Judith Mendez wrote:
> Hi Adrian,
>
> On 9/9/24 1:26 AM, Adrian Hunter wrote:
>> On 6/09/24 20:50, Judith Mendez wrote:
>>> The sdhci_start_signal_voltage_switch function sets
>>> V1P8_SIGNAL_ENA by default after switching to 1v8 signaling.
>>> V1P8_SIGNAL_ENA determines whether to launch cmd/data on neg
>>> edge or pos edge of clock.
>>>
>>> Due to some eMMC and SD failures seen across am62x platform,
>>> do not set V1P8_SIGNAL_ENA by default, only enable the bit
>>> for devices that require this bit in order to switch to 1v8
>>> voltage for uhs modes.
>>>
>>> Signed-off-by: Judith Mendez <jm@xxxxxx>
>>> ---
>>> drivers/mmc/host/sdhci_am654.c | 86 ++++++++++++++++++++++++++++++++++
>>> 1 file changed, 86 insertions(+)
>>>
>>> diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c
>>> index 0aa3c40ea6ed8..fb6232e56606b 100644
>>> --- a/drivers/mmc/host/sdhci_am654.c
>>> +++ b/drivers/mmc/host/sdhci_am654.c
>>> @@ -155,6 +155,7 @@ struct sdhci_am654_data {
>>> u32 tuning_loop;
>>> #define SDHCI_AM654_QUIRK_FORCE_CDTEST BIT(0)
>>> +#define SDHCI_AM654_QUIRK_SET_V1P8_ENA BIT(1)
>>
>> It would be better for the quirk to represent the deviation
>> from normal i.e.
>>
>> #define SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA BIT(1)
>>
>>> };
>>> struct window {
>>> @@ -356,6 +357,79 @@ static void sdhci_j721e_4bit_set_clock(struct sdhci_host *host,
>>> sdhci_set_clock(host, clock);
>>> }
>>> +int sdhci_am654_start_signal_voltage_switch(struct mmc_host *mmc,
>>> + struct mmc_ios *ios)
>>
>> Simpler to call sdhci_start_signal_voltage_switch() for the normal
>> case e.g.
>
> This is simpler, so sure will use thanks.
>
>>
>> static int sdhci_am654_start_signal_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
>> {
>> struct sdhci_host *host = mmc_priv(mmc);
>> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>> struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
>>
>>
>> if ((sdhci_am654->quirks & SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA) &&
>> ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
>> ret = mmc_regulator_set_vqmmc(mmc, ios);
>> if (ret < 0) {
>> pr_warn("%s: Switching to 1.8V signalling voltage failed\n",
>> mmc_hostname(mmc));
>> return -EIO;
>> }
>> return 0;
>> }
>>
>> return sdhci_start_signal_voltage_switch(mmc, ios);
>> }
>>
>>> +{
>>> + struct sdhci_host *host = mmc_priv(mmc);
>>> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>> + struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
>>> + u16 ctrl;
>>> + int ret;
>>> +
>>> + if (host->version < SDHCI_SPEC_300)
>>> + return 0;
>>> +
>>> + switch (ios->signal_voltage) {
>>> + case MMC_SIGNAL_VOLTAGE_330:
>>> + if (!(host->flags & SDHCI_SIGNALING_330))
>>> + return -EINVAL;
>>> +
>>> + ctrl &= ~SDHCI_CTRL_VDD_180;
>>> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
>>> +
>>> + if (!IS_ERR(mmc->supply.vqmmc)) {
>>> + ret = mmc_regulator_set_vqmmc(mmc, ios);
>>> + if (ret < 0) {
>>> + pr_warn("%s: Switching to 3.3V signalling voltage failed\n",
>>> + mmc_hostname(mmc));
>>> + return -EIO;
>>> + }
>>> + }
>>> +
>>> + usleep_range(5000, 5500);
>>> +
>>> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>>> + if (!(ctrl & SDHCI_CTRL_VDD_180))
>>> + return 0;
>>> +
>>> + pr_warn("%s: 3.3V regulator output did not become stable\n",
>>> + mmc_hostname(mmc));
>>> +
>>> + return -EAGAIN;
>>> +
>>> + case MMC_SIGNAL_VOLTAGE_180:
>>> + if (!(host->flags & SDHCI_SIGNALING_180))
>>> + return -EINVAL;
>>> +
>>> + if (!IS_ERR(mmc->supply.vqmmc)) {
>>> + ret = mmc_regulator_set_vqmmc(mmc, ios);
>>> + if (ret < 0) {
>>> + pr_warn("%s: Switching to 1.8V signalling voltage failed\n",
>>> + mmc_hostname(mmc));
>>> + return -EIO;
>>> + }
>>> + }
>>> +
>>> + if (sdhci_am654->quirks & SDHCI_AM654_QUIRK_SET_V1P8_ENA) {
>>> + ctrl |= SDHCI_CTRL_VDD_180;
>>> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
>>> +
>>> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>>> + if (ctrl & SDHCI_CTRL_VDD_180)
>>> + return 0;
>>> +
>>> + pr_warn("%s: 1.8V regulator output did not become stable\n",
>>> + mmc_hostname(mmc));
>>> +
>>> + return -EAGAIN;
>>> + }
>>> + return 0;
>>> +
>>> + default:
>>> + return 0;
>>> + }
>>> +}
>>> +
>>> static u8 sdhci_am654_write_power_on(struct sdhci_host *host, u8 val, int reg)
>>> {
>>> writeb(val, host->ioaddr + reg);
>>> @@ -801,6 +875,8 @@ static int sdhci_am654_get_of_property(struct platform_device *pdev,
>>> struct sdhci_am654_data *sdhci_am654)
>>> {
>>> struct device *dev = &pdev->dev;
>>> + struct device_node *np = dev->of_node;
>>> + struct device_node *node;
>>> int drv_strength;
>>> int ret;
>>> @@ -844,6 +920,15 @@ static int sdhci_am654_get_of_property(struct platform_device *pdev,
>>> if (device_property_read_bool(dev, "ti,fails-without-test-cd"))
>>> sdhci_am654->quirks |= SDHCI_AM654_QUIRK_FORCE_CDTEST;
>>> + node = of_parse_phandle(np, "vmmc-supply", 0);
>>> +
>>> + if (node) {
>>> + node = of_parse_phandle(np, "vqmmc-supply", 0);
>>> +
>>> + if (!node)
>>> + sdhci_am654->quirks |= SDHCI_AM654_QUIRK_SET_V1P8_ENA;
>>> + }
>>
>> It would be simpler without 'np' and 'node'. Not sure
>> what the rule is meant to be, but it could be something like:
>>
>> if (of_parse_phandle(dev->of_node, "vmmc-supply", 0) &&
>> of_parse_phandle(dev->of_node, "vqmmc-supply", 0)
>> sdhci_am654->quirks |= SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA;
>
> My issue with this is that I also need the quirk (SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA) for eMMC. DT node for eMMC does
> not include vmmc and vqmmc supplies. That is why I had the quirk logic
> inverted.
Ideally there would be a more direct way to distinguish eMMC, but
otherwise, having both supplies or neither would be:
if (!!of_parse_phandle(dev->of_node, "vmmc-supply", 0) ==
!!of_parse_phandle(dev->of_node, "vqmmc-supply", 0))
sdhci_am654->quirks |= SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA;
>
> This patch fixes timing issues with both eMMC and SD. (:
>
> ~ Judith
>
>
>>
>>> +
>>> sdhci_get_of_property(pdev);
>>> return 0;
>>> @@ -940,6 +1025,7 @@ static int sdhci_am654_probe(struct platform_device *pdev)
>>> goto err_pltfm_free;
>>> }
>>> + host->mmc_host_ops.start_signal_voltage_switch = sdhci_am654_start_signal_voltage_switch;
>>> host->mmc_host_ops.execute_tuning = sdhci_am654_execute_tuning;
>>> pm_runtime_get_noresume(dev);
>>>
>>> base-commit: cf6444ba528f043398b112ac36e041a4d8685cb1
>>
>>
>
