From: Kaustabh Chakraborty <kauschluss@disroot.org>
Date: Wed, 15 Apr 2026 15:02:09 +0000 (+0530)
Subject: mmc: dw_mmc: exynos: increase DMA threshold value for exynos7870
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=65c132fa8c93a75b27860c3f03593937d8dc2c41;p=thirdparty%2Flinux.git

mmc: dw_mmc: exynos: increase DMA threshold value for exynos7870

Exynos 7870 compatible controllers, such as SDIO ones are not able to
perform DMA transfers for small sizes of data (~16 to ~512 bytes),
resulting in cache issues in subsequent transfers. Increase the DMA
transfer threshold to 512 to allow the shorter transfers to take place,
bypassing DMA.

Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---

diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
index 261344d3a8cfe..4b76b997ddc15 100644
--- a/drivers/mmc/host/dw_mmc-exynos.c
+++ b/drivers/mmc/host/dw_mmc-exynos.c
@@ -141,6 +141,7 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU) {
 		/* Quirk needed for certain Exynos SoCs */
 		host->quirks |= DW_MMC_QUIRK_FIFO64_32;
+		host->dma_threshold = 512;
 	}
 
 	if (priv->ctrl_type == DW_MCI_TYPE_ARTPEC8) {