Re: [PATCH] mmc: dwmmc: only clear handled interrupts

16 Sep 2022

On 9/15/22 19:56, John Keeping wrote:
...
Unconditionally clearing DTO when RXDR is set leads to spurious timeouts
in FIFO mode transfers if events occur in the following order:
mask = dwmci_readl(host, DWMCI_RINTSTS);
// Hardware asserts DWMCI_INTMSK_DTO here
dwmci_writel(host, DWMCI_RINTSTS, DWMCI_INTMSK_DTO);
if (mask & DWMCI_INTMSK_DTO) {
   	// Unreachable as DTO is cleared without being handled!
   	return 0;
   }
Only clear interrupts that we have seen and are handling so that DTO is
not missed.
Signed-off-by: John Keeping john@metanate.com
drivers/mmc/dw_mmc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
index 4232c5eb8c..5085a3b491 100644
--- a/drivers/mmc/dw_mmc.c
+++ b/drivers/mmc/dw_mmc.c
@@ -168,7 +168,8 @@ static int dwmci_data_transfer(struct dwmci_host *host, struct mmc_data *data)
   		if (data->flags == MMC_DATA_READ &&
   		    (mask & (DWMCI_INTMSK_RXDR | DWMCI_INTMSK_DTO))) {
   			dwmci_writel(host, DWMCI_RINTSTS,

			     DWMCI_INTMSK_RXDR | DWMCI_INTMSK_DTO);




			     mask & (DWMCI_INTMSK_RXDR |


				     DWMCI_INTMSK_DTO));
	while (size) {
		ret = dwmci_fifo_ready(host,
				DWMCI_FIFO_EMPTY,



Tested-by: Jerome Forissier jerome.forissier@linaro.org (Rock PI 4B)
Boot logs:
- 2022.04 without this patch:
[...]
U-Boot SPL 2022.04 (Apr 04 2022 - 14:31:32 +0000)
Trying to boot from MMC1
## Checking hash(es) for config config_1 ... sha1,rsa2048:dev+ OK
## Checking hash(es) for Image atf_1 ... sha1+ sha1,rsa2048:dev+ OK
## Checking hash(es) for Image uboot ... sha1+ sha1,rsa2048:dev+ OK
## Checking hash(es) for Image fdt_1 ... sha1+ sha1,rsa2048:dev+ OK
spl_load_simple_fit: can't load image loadables index 1 (ret = -5)
mmc_load_image_raw_sector: mmc block read error
[...]
- 2022.04 with this patch:
[...]
U-Boot SPL 2022.04 (Apr 04 2022 - 14:31:32 +0000)
Trying to boot from MMC1
## Checking hash(es) for config config_1 ... sha1,rsa2048:dev+ OK
## Checking hash(es) for Image atf_1 ... sha1+ sha1,rsa2048:dev+ OK
## Checking hash(es) for Image uboot ... sha1+ sha1,rsa2048:dev+ OK
## Checking hash(es) for Image fdt_1 ... sha1+ sha1,rsa2048:dev+ OK
## Checking hash(es) for Image atf_2 ... sha1+ sha1,rsa2048:dev+ OK
## Checking hash(es) for Image atf_3 ... sha1+ sha1,rsa2048:dev+ OK
## Checking hash(es) for Image atf_4 ... sha1+ sha1,rsa2048:dev+ OK
NOTICE:  BL31: v2.6(debug):v2.6-879-gc3bdd3d3cf-dirty
[...]
Thanks,
-- 
Jerome

    