Am 22.07.2018 um 23:19 schrieb Andreas Färber: > From: Ian Pozella <Ian.Pozella@xxxxxxxxxx> > > The mmc block in Pistachio allows 1 to 8 data bits to be used. > Marduk uses 4 bits allowing the upper 4 bits to be allocated > to the Mikrobus ports. However these bits are still connected > internally meaning the mmc block recieves signals on all data lines "receives" I had fixed a number of typos from the downstream patches already, but this one slipped through. Regards, Andreas > and seems the internal HW CRC checks get corrupted by this erroneous > data. > > We cannot control what data is sent on these lines because they go > to external ports. 1 bit mode does not exhibit the issue hence the > safe default is to use this. If a user knows that in their use case > they will not use the upper bits then they can set to 4 bit mode in > order to improve performance. > > Also make sure that the upper 4 bits don't get allocated to the mmc > driver (the default is to assign all 8 pins) so they can be allocated > to other drivers. Allocating all 4 despite setting 1 bit mode as this > matches what is there in hardware. > > Signed-off-by: Ian Pozella <Ian.Pozella@xxxxxxxxxx> > Signed-off-by: Andreas Färber <afaerber@xxxxxxx> [snip] -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
