A3720 - Disable slot when eMMC is not present

[Andre Heider]

On 08/12/2020 11:08, Pali Rohár wrote:
> Hello! I looked at what is initialized and enabled for sd/emmc slots and
> I found out that comphy mmc needs to be enabled if at least one slot is
> used (e.g. SD card) and then remaining part is slot initialization in
> xenon driver.
> 
> I wrote quick patch to disable slot when unregistering mmc device from
> U-Boot and also unregister emmc on A3720 from U-Boot when it is not
> present. But I have not tested it yet.
> 
> What do you think about it?

I haven't tested this yet, but it looks like it should leave the hw in a 
state as it was on a non-emmc board before the emmc/non-emmc merge. So I 
like the idea!

You can merge your xenon_mmc_disable_slot() with xenon_mmc_enable_slot() 
though, and instead add a 'bool enable' as with xenon_mmc_set_acg() above.

Thanks,
Andre

> 
> diff --git a/board/Marvell/mvebu_armada-37xx/board.c b/board/Marvell/mvebu_armada-37xx/board.c
> index f67b04b78c..1b9e7520cc 100644
> --- a/board/Marvell/mvebu_armada-37xx/board.c
> +++ b/board/Marvell/mvebu_armada-37xx/board.c
> @@ -5,6 +5,7 @@
>   
>   #include <common.h>
>   #include <dm.h>
> +#include <dm/device-internal.h>
>   #include <env.h>
>   #include <i2c.h>
>   #include <init.h>
> @@ -84,12 +85,10 @@ int board_init(void)
>   #ifdef CONFIG_BOARD_LATE_INIT
>   int board_late_init(void)
>   {
> +	struct udevice *dev;
>   	struct mmc *mmc_dev;
>   	bool ddr4, emmc;
>   
> -	if (env_get("fdtfile"))
> -		return 0;
> -
>   	if (!of_machine_is_compatible("globalscale,espressobin"))
>   		return 0;
>   
> @@ -101,6 +100,16 @@ int board_late_init(void)
>   	mmc_dev = find_mmc_device(1);
>   	emmc = (mmc_dev && mmc_init(mmc_dev) == 0);
>   
> +	/* if eMMC is not present then remove it from DM */
> +	if (!emmc && mmc_dev) {
> +		dev = mmc_dev->dev;
> +		device_remove(dev, DM_REMOVE_NORMAL);
> +		device_unbind(dev);
> +	}
> +
> +	if (env_get("fdtfile"))
> +		return 0;
> +
>   	if (ddr4 && emmc)
>   		env_set("fdtfile", "marvell/armada-3720-espressobin-v7-emmc.dtb");
>   	else if (ddr4)
> diff --git a/drivers/mmc/xenon_sdhci.c b/drivers/mmc/xenon_sdhci.c
> index 6ce9d00d0a..da9882cbf6 100644
> --- a/drivers/mmc/xenon_sdhci.c
> +++ b/drivers/mmc/xenon_sdhci.c
> @@ -350,6 +350,16 @@ static void xenon_mmc_enable_slot(struct sdhci_host *host, u8 slot)
>   	sdhci_writel(host, var, SDHC_SYS_OP_CTRL);
>   }
>   
> +/* Disable specific slot */
> +static void xenon_mmc_disable_slot(struct sdhci_host *host, u8 slot)
> +{
> +	u32 var;
> +
> +	var = sdhci_readl(host, SDHC_SYS_OP_CTRL);
> +	var &= ~(SLOT_MASK(slot) << SLOT_ENABLE_SHIFT);
> +	sdhci_writel(host, var, SDHC_SYS_OP_CTRL);
> +}
> +
>   /* Enable Parallel Transfer Mode */
>   static void xenon_mmc_enable_parallel_tran(struct sdhci_host *host, u8 slot)
>   {
> @@ -515,6 +525,14 @@ static int xenon_sdhci_probe(struct udevice *dev)
>   	return ret;
>   }
>   
> +static int xenon_sdhci_remove(struct udevice *dev)
> +{
> +	struct sdhci_host *host = dev_get_priv(dev);
> +
> +	xenon_mmc_disable_slot(host, XENON_MMC_SLOT_ID_HYPERION);
> +	return 0;
> +}
> +
>   static int xenon_sdhci_ofdata_to_platdata(struct udevice *dev)
>   {
>   	struct sdhci_host *host = dev_get_priv(dev);
> @@ -564,6 +582,7 @@ U_BOOT_DRIVER(xenon_sdhci_drv) = {
>   	.ops		= &sdhci_ops,
>   	.bind		= xenon_sdhci_bind,
>   	.probe		= xenon_sdhci_probe,
> +	.remove		= xenon_sdhci_remove,
>   	.priv_auto_alloc_size = sizeof(struct xenon_sdhci_priv),
>   	.platdata_auto_alloc_size = sizeof(struct xenon_sdhci_plat),
>   };
>