Re: 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),
  };