[PATCH 17/17] mmc: rockchip_sdhci: Limit number of blocks read in a single command

[Jonas Karlman]

Using DMA to load TF-A into SRAM fails when booting from eMMC on RK3588.

  ## Checking hash(es) for Image atf-3 ... sha256 error!
  Bad hash value for 'hash' hash node in 'atf-3' image node
  spl_load_simple_fit: can't load image loadables index 2 (ret = -1)
  mmc_load_image_raw_sector: mmc block read error

Fix this by using PIO mode in SPL and limit the number of blocks used in
a single read command to avoid triggering Data End Bit Error interrupt.

Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
---
 configs/rock5b-rk3588_defconfig | 1 +
 drivers/mmc/rockchip_sdhci.c    | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/configs/rock5b-rk3588_defconfig b/configs/rock5b-rk3588_defconfig
index 3fcc6a26bb51..d3136ac850fe 100644
--- a/configs/rock5b-rk3588_defconfig
+++ b/configs/rock5b-rk3588_defconfig
@@ -58,6 +58,7 @@ CONFIG_MMC_DW=y
 CONFIG_MMC_DW_ROCKCHIP=y
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_SDMA=y
+# CONFIG_SPL_MMC_SDHCI_SDMA is not set
 CONFIG_MMC_SDHCI_ROCKCHIP=y
 CONFIG_ETH_DESIGNWARE=y
 CONFIG_GMAC_ROCKCHIP=y
diff --git a/drivers/mmc/rockchip_sdhci.c b/drivers/mmc/rockchip_sdhci.c
index 9178bc00b6b8..932856911ae7 100644
--- a/drivers/mmc/rockchip_sdhci.c
+++ b/drivers/mmc/rockchip_sdhci.c
@@ -596,6 +596,14 @@ static int rockchip_sdhci_probe(struct udevice *dev)
 	if (ret)
 		return ret;
 
+	/*
+	 * Reading more than 4 blocks with a single CMD18 command in PIO mode
+	 * triggers Data End Bit Error on RK3568 and RK3588. Limit to reading
+	 * max 4 blocks in one command when using PIO mode.
+	 */
+	if (!(host->flags & USE_DMA))
+		cfg->b_max = 4;
+
 	return sdhci_probe(dev);
 }
 
-- 
2.40.0