Messages in this thread | | | Date | Tue, 29 Jul 2008 08:30:09 +0200 | From | "pHilipp Zabel" <> | Subject | Re: [PATCH] fix misalignment in pxamci |
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On Mon, Jul 28, 2008 at 6:23 PM, Uli Luckas <u.luckas@road.de> wrote: > On Saturday, 5. July 2008, pHilipp Zabel wrote: >> On Sat, Jul 5, 2008 at 2:19 AM, Marek Vasut <marek.vasut@gmail.com> wrote: >> > Hi, >> > Philipp Zabel finally made the pxamci issue clear. It turned out, that >> > pxamci needs the DMA destination address to be aligned to 8 bytes. In >> > some cases it happened, that the address was aligned to 4 bytes causing >> > controller to incorrectly transfer data (and resulting into error like >> > "mmc0: unrecognised SCR structure version 1"). The following patch allows >> > to debug this issue and moreover fixes it by moving one 4 byte entry of >> > mmc_card structure, aligning the DMA destination back to 8 bytes. >> > >> > Signed-off-by: Marek Vasut <marek.vasut@gmail.com> >> >> We can enable byte aligned transfers on the DMA controller. This is >> what I came up with yesterday: >> (sorry for wrapped lines - the proper patch should probably be a >> combination of both >> warning/DALGN handling and and moving something in mmc_card around). >> > Hi Philipp, > this driver is not only for pxa27x but for pxa25x as well and pxa25x can't > handle unaligned DMA. > Shouldn't Marek Vasut's patch be included for the PXA25x case?
Argh, DALGN shouldn't be defined in pxa-regs.h. We really need an aligned SCR target then. Pierre, is there any way we can have the MMC core align DMA targets for pxa25x?
Just moving elements of the mmc_card structure around seems to be good enough, but I fear this will break again as soon as the next person forgets about pxamci's special needs on pxa25x.
regards Philipp
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