Re: [PATCH v2 2/7] mmc: sdhci-pxav3: Fix Armada 38x controller's caps according to erratum ERR-7878951

Gregory CLEMENT
2015-01-23T14:18:54Z

Hi Marcin,

On 23/01/2015 12:33, Marcin Wojtas wrote:
> Dear Gregory,
>
>
>> @@ -118,8 +118,11 @@ static int mv_conf_mbus_windows(struct platform_device *pdev,
>> return 0;
>> }
>>
>> -static int armada_38x_quirks(struct sdhci_host *host)
>> +static int armada_38x_quirks(struct platform_device *pdev,
>> + struct sdhci_host *host)
>> {
>> + struct device_node *np = pdev->dev.of_node;
>> +
>> host->quirks |= SDHCI_QUIRK_MISSING_CAPS;
>> /*
>> * According to erratum 'FE-2946959' both SDR50 and DDR50
>> @@ -129,6 +132,20 @@ static int armada_38x_quirks(struct sdhci_host *host)
>> */
>> host->caps1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
>> host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_DDR50);
>> +
>> + /*
>> + * According to erratum 'ERR-7878951' Armada 38x SDHCI
>> + * controller has different capabilities than the ones shown
>> + * in its registers
>> + */
>> + host->caps = sdhci_readl(host, SDHCI_CAPABILITIES);
>> + if (of_get_property(np, "no-1-8-v", NULL)) {
>> + host->caps &= ~SDHCI_CAN_VDD_180;
>> + host->mmc->caps &= ~MMC_CAP_1_8V_DDR;
>> + } else
>> + host->caps &= ~SDHCI_CAN_VDD_330;
>
> In this "else" there is one thing missing
> host->mmc->caps |= MMC_CAP_1_8V_DDR;
> because it's not set by default, however it's not a must - please see
> my remark below.
>
>> + host->caps1 &= ~(SDHCI_SUPPORT_SDR104 | SDHCI_USE_SDR50_TUNING);
>> +
>> return 0;
>> }
>>
>> @@ -333,7 +350,7 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
>> clk_prepare_enable(pxa->clk_core);
>>
>> if (of_device_is_compatible(np, "marvell,armada-380-sdhci")) {
>> - ret = armada_38x_quirks(host);
>> + ret = armada_38x_quirks(pdev, host);
>> if (ret < 0)
>> goto err_quirks;
>> ret = mv_conf_mbus_windows(pdev, mv_mbus_dram_info());
>> @@ -341,9 +358,6 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
>> goto err_mbus_win;
>> }
>>
>> - /* enable 1/8V DDR capable */
>> - host->mmc->caps |= MMC_CAP_1_8V_DDR;
>> -
>
> Now, with this change MMC_CAP_1_8V_DDR is disabled for devices other
> than Armada 38x, that use sdhci-pxav3. There are two options:
> 1. Move those lines above the place where armada_38x_quirks is called
> (IMO the easiest option - 'else' in this function would not need to be
> supplemented, as I pointed above)
> 2. Leave it "as is" here, but a condition below is needed (+
> supplementation of 'else' in armada_38x_quirks)
> if (!of_device_is_compatible(np, "marvell,armada-380-sdhci"))
>

I will take the first option.

A third version is coming soon addressing also Mark's comments.

Thanks,

Gregory

--
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.