Hi Viresh,
On 8/21/2012 12:42 PM, viresh kumar wrote: > I have added linux-kernel list in cc as there might be other users of > this patch. > Also, please try to keep spear-devel list in cc for dw_dmac as we are using > this > driver for SPEAr. Yes sure, I didn't want to bother the lists with the first preparations of this patch. > On Sun, Aug 19, 2012 at 9:36 PM, Hein Tibosch <hein_tibo...@yahoo.es> wrote: >> dw_dmac: >> - After 2.6.39, the registers were accessed using readl/writel >> in stead of the __raw_readl and __raw_writel causing a 16-bit >> swap of all values (little endian access) > Ahhhh!! Firstly we can't use __raw* for architectures >= ARMv6. It is not > only for endianess but for memory barriers. Why are they getting swapped > for your case? Does your processor and dw_dmac have different endianess? If I'm not wrong: the __raw_* functions will access the i/o memory in native endianess. As far as I know, all AVR32 drivers are currently using the __raw* functions. I never encountered a problem with that. > And if i am not wrong, we should always try not to use __raw* variants just > due to endianess things... instead use either readl/writel OR > readl_/writel_ relaxed. > I am not sure if relaxed versions are available for architectures > other than ARM. Would you agree to have this depend on CONFIG_AVR ? >> - Access to memory was sometimes done in chunks of 64-bits, >> which gives an undefined value of 0x03 for SRC/DST_TR_WIDTH >> field in the CTLxL register > Looks fine. But there should be a separate patch for this. > >> - The SMS field in the CTLxL register received the wrong value: >> 0 in stead of 1 > I believe it is not for dw_dmac? That's correct, I'll put it in a separate Atmel patch (at32ap700x.c) So for the AP700x fixes for the MCI/DMA driver I'm thinking of this series of patches: To you, cc spear-devel & linux-kernel - include/linux/dw_dmac.h: adding field max_mem_width to limit SRC/DST_TR_WIDTH - dw_dmac.c: check max_mem_width before setting SRC/DST_TR_WIDTH - dw_dmac_regs.h: use __raw* functions for AVR32, readl/writel for all others To Ludovic Desroches, linux-mmc: - atmel-mci.c: avoid using peripheral DMA controller (PDC) in case of AVR32 - atmel-mci.c: only use the ATMCI_DMA register if supported by arch To Hans-Christian, linux-kernel cc Andrew: - at32ap700x.c: set src_master=1 to get SMS (Source Master Select) correct set max_mem_width=2 to get SRC/DST_TR_WIDTH correct Ok? Thanks, Hein -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
