[PATCH] uboot-mvebu: backport patch to fix eMMC

[Robert Marko]

v2022.01 has a regression that broke eMMC usage on most if not all Armada
SoC-s, thus breaking boards like uDPU which use eMMC for storage.

Fix it by backporting a recent upstream patch.

Fixes: 782d4c8306c8 ("uboot-mvebu: update to version 2022.01")
Signed-off-by: Robert Marko <robert.marko at sartura.hr>
---
 ...enon_sdhci-remove-wait_dat0-SDHCI-OP.patch | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 package/boot/uboot-mvebu/patches/013-mmc-xenon_sdhci-remove-wait_dat0-SDHCI-OP.patch

diff --git a/package/boot/uboot-mvebu/patches/013-mmc-xenon_sdhci-remove-wait_dat0-SDHCI-OP.patch b/package/boot/uboot-mvebu/patches/013-mmc-xenon_sdhci-remove-wait_dat0-SDHCI-OP.patch
new file mode 100644
index 0000000000..3277638784
--- /dev/null
+++ b/package/boot/uboot-mvebu/patches/013-mmc-xenon_sdhci-remove-wait_dat0-SDHCI-OP.patch
@@ -0,0 +1,64 @@
+From 0f3466f52fbacce67e147b9234e6323edff26a6d Mon Sep 17 00:00:00 2001
+From: Robert Marko <robert.marko at sartura.hr>
+Date: Fri, 11 Mar 2022 19:14:07 +0100
+Subject: [PATCH] mmc: xenon_sdhci: remove wait_dat0 SDHCI OP
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Generic SDHCI driver received support for checking the busy status by
+polling the DAT[0] level instead of waiting for the worst MMC switch time.
+
+Unfortunately, it appears that this does not work for Xenon controllers
+despite being a part of the standard SDHCI registers and the Armada 3720
+datasheet itself telling that BIT(20) is useful for detecting the DAT[0]
+busy signal.
+
+I have tried increasing the timeout value, but I have newer managed to
+catch DAT_LEVEL bits change from 0 at all.
+
+This issue appears to hit most if not all SoC-s supported by Xenon driver,
+at least A3720, A8040 and CN9130 have non working eMMC currently.
+
+So, until a better solution is found drop the wait_dat0 OP for Xenon.
+I was able to only test it on A3720, but it should work for others as well.
+
+Fixes: 40e6f52454fc ("drivers: mmc: Add wait_dat0 support for sdhci driver")
+Signed-off-by: Robert Marko <robert.marko at sartura.hr>
+Reviewed-by: Marek Behún <marek.behun at nic.cz>
+Reviewed-by: Jaehoon Chung <jh80.chung at samsung.com>
+Reviewed-by: Stefan Roese <sr at denx.de>
+---
+ drivers/mmc/xenon_sdhci.c | 7 ++++++-
+ 1 file changed, 6 insertions(+), 1 deletion(-)
+
+--- a/drivers/mmc/xenon_sdhci.c
++++ b/drivers/mmc/xenon_sdhci.c
+@@ -439,6 +439,8 @@ static const struct sdhci_ops xenon_sdhc
+ 	.set_ios_post = xenon_sdhci_set_ios_post
+ };
+ 
++static struct dm_mmc_ops xenon_mmc_ops;
++
+ static int xenon_sdhci_probe(struct udevice *dev)
+ {
+ 	struct xenon_sdhci_plat *plat = dev_get_plat(dev);
+@@ -452,6 +454,9 @@ static int xenon_sdhci_probe(struct udev
+ 	host->mmc->dev = dev;
+ 	upriv->mmc = host->mmc;
+ 
++	xenon_mmc_ops = sdhci_ops;
++	xenon_mmc_ops.wait_dat0 = NULL;
++
+ 	/* Set quirks */
+ 	host->quirks = SDHCI_QUIRK_WAIT_SEND_CMD | SDHCI_QUIRK_32BIT_DMA_ADDR;
+ 
+@@ -568,7 +573,7 @@ U_BOOT_DRIVER(xenon_sdhci_drv) = {
+ 	.id		= UCLASS_MMC,
+ 	.of_match	= xenon_sdhci_ids,
+ 	.of_to_plat = xenon_sdhci_of_to_plat,
+-	.ops		= &sdhci_ops,
++	.ops		= &xenon_mmc_ops,
+ 	.bind		= xenon_sdhci_bind,
+ 	.probe		= xenon_sdhci_probe,
+ 	.remove		= xenon_sdhci_remove,
-- 
2.35.1