On 11/04/2015 08:11 PM, Mark Brown wrote: > On Tue, Nov 03, 2015 at 03:36:11PM +0530, Vignesh R wrote: > >> + ti_qspi_enable_memory_map(spi); >> + ti_qspi_setup_mmap_read(spi, read_opcode, addr_width, >> + dummy_bytes); >> + memcpy_fromio(buf, qspi->mmap_base + from, len); >> + *retlen = len; >> + ti_qspi_disable_memory_map(spi); > > We'll be constantly enabling and disabling memory mapping with this. > I'm not sure that's a meaningful cost given that it doesn't actually > remap anything but rather just switches hardware modes, we can always > optimise it later if it is. > Hmm, I will move the ti_qspi_disable_memory_map() call to ti_qspi_start_transfer_one(), so that mmap mode is disabled only when normal SPI bus transfer is requested. Further, "mmap_enabled" status flag can be used to determine whether mode switch is required or not. This should help to overcome enabling and disabling memory mapping between successive mmap read requests. -- Regards Vignesh -- 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