Hi Jagan, On Thu, Dec 3, 2015 at 6:24 PM, Jagan Teki <jt...@openedev.com> wrote: > Hi Bin, > > On 3 December 2015 at 10:14, Bin Meng <bmeng...@gmail.com> wrote: >> Hi Simon, >> >> On Thu, Dec 3, 2015 at 5:05 AM, Simon Glass <s...@chromium.org> wrote: >>> +Jagan >>> >>> Hi Bin, >>> >>> On 1 December 2015 at 18:41, Bin Meng <bmeng...@gmail.com> wrote: >>>> >>>> Hi Simon, >>>> >>>> On Wed, Dec 2, 2015 at 12:32 AM, Simon Glass <s...@chromium.org> wrote: >>>> > Hi Bin, >>>> > >>>> > On 28 November 2015 at 05:45, Bin Meng <bmeng...@gmail.com> wrote: >>>> >> Every board has one dedicated type of SPI flash, hence it is >>>> >> unnecessary to include multiple SPI flash drivers. >>>> >> >>>> >> For QEMU and coreboot (default build of coreboot is also QEMU), >>>> >> SPI flash is not supported. Remove those SPI flash drivers. >>>> >> >>>> >> Signed-off-by: Bin Meng <bmeng...@gmail.com> >>>> >> --- >>>> >> >>>> >> configs/bayleybay_defconfig | 2 -- >>>> >> configs/chromebook_link_defconfig | 2 -- >>>> >> configs/chromebox_panther_defconfig | 2 -- >>>> >> configs/coreboot-x86_defconfig | 4 ---- >>>> >> configs/crownbay_defconfig | 3 --- >>>> >> configs/galileo_defconfig | 2 -- >>>> >> configs/minnowmax_defconfig | 3 --- >>>> >> configs/qemu-x86_defconfig | 4 ---- >>>> >> 8 files changed, 22 deletions(-) >>>> > >>>> > What is the benefit of this? I see it removes a few lines in a data >>>> > table. Does it matter? >>>> >>>> Maybe we should ask the other way around, why do we create so many >>>> flash driver Kconfig option? I believe the intention was footprint. >>>> Besides the footprint issue, having just one flash driver in each >>>> board makes it very clear instead of causing confusion. Looks other >>>> board defconfig files only select one. > > Are you talking about flash vendor config or CONFIG_SPI_FLASH? >
Flash vendor config, as you see in this patch. >>> >>> They are a hangover from when we had a separate driver for each one. >>> Jagan put a lot of effort into removing all the semi-duplicated code. >>> >>> Maybe we should prune down these options? >>> >> >> But if we already spent a lot of effort into removing all the >> semi-duplicated code, we should not have converted those flash driver >> to Kconfig options before. >> >> See commit d5af92315bb48740f16bf8817f38e227d3076905 "sf: kconfig: add >> kconfig options for spi flashes" >> >> I suspect we may remove most of these SPI flash macros, but at least >> SST flash macro should be kept since right now it is mixed in the >> generic driver with a special byte program and word program which is >> incompatible with other vendors' flashes. > > But there is some flash vendor specific code like quad enable bit, > locking ops and finally about spi_flash_params table. > I know. That's probably why adding all these SPI flash drivers don't help at all because only one code path will take effect. And what I did in this patch is to select one type of flash per board. >> >>>> >>>> > >>>> > For all of these platforms we can use the dediprog em100 which I >>>> > typically set to use winbond as the manufacturer, regardless of which >>>> > chip is actually on the board. >>>> > >>>> >>>> I think that's because emulator can emulate flash from various vendors. >>> >>> Yes, and also for convenience. >>> >>>> >>>> > For U-Boot on coreboot, why is SPI flash not supported? It certainly >>>> > works with link. >>>> >>>> Yes, booting from coreboot does support SPI flash. However since we >>>> decided to use QEMU as the default build target for coreboot, and QEMU >>>> does not support SPI flash yet, these config options are removed. One >>>> can certainly adjust these Kconfig options via 'make menuconfig', eg: >>>> adding SD/MMC support which is not in coreboot's defconfig either. >>> >>> Well this breaks booting on link, since the SPI flash stops working. >>> I'm really not keen on having to specially select the SPI flash when >>> you want to use link. >>> >> >> Do you mean booting U-Boot on link from coreboot? Without SPI flash it >> should still boot. It looks to me your preference is to include all >> the available drivers into coreboot's defconfig, yes? If so, we may >> add some other drivers Kconfig in coreboot-x86_defconfig too, like >> SD/MMC drivers, all the available ethernet drivers even they only >> exist on some boards. > > thanks! > -- Regards, Bin _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
