[PATCH v2] mmc: rockchip_sdhci: Fix 4 blocks PIO mode read limit for RK35xx

[Jonas Karlman]

The commit 2cc6cde647e2 ("mmc: rockchip_sdhci: Limit number of blocks
read in a single command") introduced a limit of number of blocks to
read to fix a Data End Bit Error on RK3568 and RK3588. This had a side
affect of significant slowing down reading FIT from eMMC.

After the commit 6de9d7b2f13c ("rockchip: rk35xx: Enable eMMC HS200 mode
by default") the limit of number of blocks to read workaround is no
longer necessary and at HS200+ a Data End Bit Error is no longer
happening using PIO mode.

Change this limitation to allow reading more than 4 blocks with a single
CMD18 command in PIO mode at HS200+ speed, keep using the 4 blocks
limitation when loadig FIT from eMMC at lower speed than HS200.

Fixes: 2cc6cde647e2 ("mmc: rockchip_sdhci: Limit number of blocks read in a single command")
Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
---
v2: Move cfg->b_max configuration to set_ios_post() ops

This significantly speed up FIT loading from eMMC on RK3588 boards with
a mmc-hs200 prop in the sdhci node, and boards without a mmc-hs200 prop
continue to work.
---
 drivers/mmc/rockchip_sdhci.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/mmc/rockchip_sdhci.c b/drivers/mmc/rockchip_sdhci.c
index 706fb1235796..c889c7bc9855 100644
--- a/drivers/mmc/rockchip_sdhci.c
+++ b/drivers/mmc/rockchip_sdhci.c
@@ -391,6 +391,8 @@ static int rk3568_sdhci_config_dll(struct sdhci_host *host, u32 clock, bool enab
 static int rk3568_sdhci_set_ios_post(struct sdhci_host *host)
 {
 	struct mmc *mmc = host->mmc;
+	struct rockchip_sdhc_plat *plat = dev_get_plat(mmc->dev);
+	struct mmc_config *cfg = &plat->cfg;
 	u32 reg;
 
 	reg = sdhci_readw(host, SDHCI_HOST_CONTROL2);
@@ -437,6 +439,20 @@ static int rk3568_sdhci_set_ios_post(struct sdhci_host *host)
 
 	sdhci_writew(host, reg, DWCMSHC_EMMC_EMMC_CTRL);
 
+	/*
+	 * Reading more than 4 blocks with a single CMD18 command in PIO mode
+	 * triggers Data End Bit Error using a slower mode than HS200. Limit to
+	 * reading max 4 blocks in one command when using PIO mode.
+	 */
+	if (!(host->flags & USE_DMA)) {
+		if (mmc->selected_mode == MMC_HS_200 ||
+		    mmc->selected_mode == MMC_HS_400 ||
+		    mmc->selected_mode == MMC_HS_400_ES)
+			cfg->b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
+		else
+			cfg->b_max = 4;
+	}
+
 	return 0;
 }
 
@@ -598,16 +614,6 @@ static int rockchip_sdhci_probe(struct udevice *dev)
 	    dev_read_bool(dev, "u-boot,spl-fifo-mode"))
 		host->flags &= ~USE_DMA;
 
-	/*
-	 * 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) &&
-	    (device_is_compatible(dev, "rockchip,rk3568-dwcmshc") ||
-	     device_is_compatible(dev, "rockchip,rk3588-dwcmshc")))
-		cfg->b_max = 4;
-
 	return sdhci_probe(dev);
 }
 
-- 
2.43.2