On Wed, Nov 28, 2018 at 10:56:01PM +0530, Vignesh R wrote:
U-Boot SPI NOR support (sf layer) is quite outdated as it does not support 4 byte addressing opcodes, SFDP table and different types of quad mode enable sequences. Many newer flashes no longer support BANK registers use by sf layer to a access >16MB space. Also, many SPI controllers have special MMIO interfaces which provide accelerated read/write access but require knowledge of flash parameters to make use of it. Recent spi-mem layer provides a way to support such flashes but sf layer isnt using that. This patch series syncs SPI NOR framework from Linux v4.19. It also adds spi-mem support on top. So, we gain 4byte addressing support and SFDP support. This makes migrating to U-Boot MTD framework very easy.
Tested with few Spansion, micron and macronix flashes with TI's dra7xx, k2g, am43xx EVMs. I dont have access to flashes from other vendors. So, I would greatly appreciate testing on other platforms.
This is a RFC, if this approach if fine with the community and get an early feedback. Based on the response, I plan to post official series with better splitting of patches, removing all dead code and fixing up any checkpatch errors.
I like this approach and would like to see this go in, overall, for the v2018.04 release if at all possible. Thanks all!