On 06/25/2013 09:58 AM, Michal Simek wrote: > On 06/24/2013 10:26 AM, Alexey Brodkin wrote: >> Initially different data accessors were used for LE abd BE CPUs: >> "ioread16" in "ace_datain_be16" and "ioread16be" in "ace_datain_le16". >> The same with writes. >> >> While it worked in some cases (for example on BE PPC) it didn't work in >> others (LE ARC). > > I am not sure about this. It seems to me that what you need to do > is swapped wires in your hw design to use the same configuration > as is used on ppc and microblaze for data access. > >> Mentioned functions access data (by 16-bit chunks) from storage (i.e. >> CompactFlash card) via DATABUFREG of Xilinx SystemACE CF controller. >> And to interpret data properly CPU needs to access data in DATABUFREG >> with native endianess. > > I have had a lot of discussions about using native endianess. > This driver supports endian detection on register side > but not on data side. > Is this soft IP? If yes then just swapped wires on bus and use > standard configuration. I don't think there's a wiring problem. For starters "Xilinx SystemACE CF controller" (at least the one I'm dealing with on "Xilinx ML-509" board) is a real hardware IC (with part number XCCACE-TQ144I). And what about your HW? Is your SystemACE controller is a soft-IP? As described in corresponding datasheet (http://www.xilinx.com/support/documentation/data_sheets/ds080.pdf) CF-card is connected to this IC directly - so CPU itself doesn't have any connection to CF. CPU only can access (read/write) SystemACE's registers and by these actions: 1. Config SystemACE or read its configuration and status (registers 0x00-0x1d). 2. Read/write data from/to CF-card (register 0x40). And as long as configuration/status registers access is proven to work I expect access to data via just reads/writes from/to another same register should work as well. > Grant is driver owner and he has to decide if this is acceptable > or not. As far as I may see from latest MAINTAINERS file grant is no longer maintains it. So who may take any decision now? Arnd? > I can test it on microblaze hw. Would be very nice and helpful if you give it a shot on Microblaze HW. BTW what is an endianess of this HW? Only BE or both BE/LE? Regards, Alexey -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
