A3720 - Disable slot when eMMC is not present

["Pali Rohár" <pali@kernel.org>]

On Wednesday 09 December 2020 19:01:19 Jaehoon Chung wrote:
> Hi,
> 
> On 12/8/20 7:08 PM, Pali Roh?r 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?
> 
> Logically, it's possible to disable slot. But i'm not sure because of not having its board.
> Just minor question.. Does it support multi slot per one IP?

A3720 has only one slot with index XENON_MMC_SLOT_ID_HYPERION.

A3720 has two mmc/sd IPs at two different address spaces, so uSD and
eMMC do not share config address space.

> Best Regards,
> Jaehoon Chung
> 
> > 
> > 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),
> >  };
> > 
> > 
>