Hello! On 08/20/2018 07:38 PM, Wolfram Sang wrote: >> I have encountered an interrupt storm during the eMMC chip probing (and >> the chip finally didn't get detected). It turned out that U-Boot left >> the SDHI DMA interrupts enabled while the Linux driver didn't use those. >> Masking those interrupts in renesas_sdhi_internal_dmac_request_dma() gets >> rid of both issues... >> >> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx> > > Thanks for fixing this issue. > >> >> --- >> The patch is against Ulf Hansson's 'mmc.git' repo's 'fixes' branch. >> >> drivers/mmc/host/renesas_sdhi_internal_dmac.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> Index: mmc/drivers/mmc/host/renesas_sdhi_internal_dmac.c >> =================================================================== >> --- mmc.orig/drivers/mmc/host/renesas_sdhi_internal_dmac.c >> +++ mmc/drivers/mmc/host/renesas_sdhi_internal_dmac.c >> @@ -51,10 +51,12 @@ >> #define INFO1_CLEAR 0 >> #define INFO1_DTRANEND1 BIT(17) >> #define INFO1_DTRANEND0 BIT(16) >> +#define INFO1_RESERVED_BITS GENMASK_ULL(32, 0) > > 31? Indeed. Than RST_RESERVED_BITS (from which I copied w/o much thinking) is also wrong! > Also, RESERVED_BITS is not quite proper. Not all of those bits are > reserved. Maybe CLEAR_MASK? Indeed, would seem better... but RST_RESERVED_BITS also needs fixing then... >> /* DM_CM_INFO2 and DM_CM_INFO2_MASK */ >> #define INFO2_DTRANERR1 BIT(17) >> #define INFO2_DTRANERR0 BIT(16) >> +#define INFO2_RESERVED_BITS GENMASK_ULL(32, 0) > > Same as above. Maybe we even need one define only? No, I think 2 separate regs deserve 2 separate masks. >> + /* >> + * We don't use the DMA interrupts, but they might have been enabled >> + * by a bootloader, so mask them to avoid an interrupt storm... >> + */ > > Two spaces after ',' looks odd to me. Also, no need for "..." Both are my preferences. Yes, I probably should have worked in the typesetting industry... :-) > I'd even think with a name like CLEAR_MASK, the comment could even go. Disagree here. The register #defines don't provide enough info on what's going on... >> + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1_MASK, >> + INFO1_RESERVED_BITS); >> + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO2_MASK, >> + INFO2_RESERVED_BITS); MBR, Sergei
