From 5b2b6586c5db61267f183907f7b6fba0c2b92f3e Mon Sep 17 00:00:00 2001 From: Chevron Li Date: Tue, 23 May 2023 19:11:14 +0800 Subject: [PATCH] mmc: sdhci: fix DMA configure compatibility issue when 64bit DMA mode is used. commit 20dbd07ef0a8bc29eb03d6a95258ac8934cbe52d upstream. Bayhub SD host has hardware limitation: 1.The upper 32bit address is inhibited to be written at SD Host Register [03E][13]=0 (32bits addressing) mode, is admitted to be written only at SD Host Register [03E][13]=1 (64bits addressing) mode. 2.Because of above item#1, need to configure SD Host Register [03E][13] to 1(64bits addressing mode) before set 64bit ADMA system address's higher 32bits SD Host Register [05F~05C] if 64 bits addressing mode is used. The hardware limitation is reasonable for below reasons: 1.Normal flow should set DMA working mode first, then do DMA-transfer-related configuration, such as system address. 2.The hardware limitation may avoid the software to configure wrong higher 32bit address at 32bits addressing mode although it is redundant. The change that set 32bits/64bits addressing mode before set ADMA address, has no side-effect to other host IPs for below reason: The setting order is reasonable and standard: DMA Mode setting first and then DMA address setting. It meets all DMA setting sequence. Signed-off-by: Chevron Li Acked-by: Adrian Hunter Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230523111114.18124-1-chevron_li@126.com Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/host/sdhci.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 6323419..ad73d52 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1181,6 +1181,8 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd) } } + sdhci_config_dma(host); + if (host->flags & SDHCI_REQ_USE_DMA) { int sg_cnt = sdhci_pre_dma_transfer(host, data, COOKIE_MAPPED); @@ -1200,8 +1202,6 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd) } } - sdhci_config_dma(host); - if (!(host->flags & SDHCI_REQ_USE_DMA)) { int flags; -- 2.7.4