On Fri, Nov 23, 2018 at 1:51 AM <s...@google.com> wrote: > > On Fri, 16 Nov 2018 at 12:40, Simon Goldschmidt > <simon.k.r.goldschm...@gmail.com> wrote: > > > > On 31.10.2018 07:42, Simon Goldschmidt wrote: > > > On Wed, Oct 31, 2018 at 7:22 AM Jagan Teki <ja...@amarulasolutions.com> > > > wrote: > > >> On Wed, Oct 31, 2018 at 1:40 AM Simon Goldschmidt > > >> <simon.k.r.goldschm...@gmail.com> wrote: > > >>> When the device tree is missing a correct spi slave description below > > >>> the bus (compatible "spi-flash" or spi-max-frequency are missing), > > >>> the 'set_speed' callback can be called with 'speed' == 0 Hz. > > >>> At least with cadence qspi, this leads to a division by zero. > > >>> > > >>> Prevent this by initializing speed to 100 kHz in this case (same > > >>> fallback value as is done in 'dm_spi_claim_bus') and issue a warning > > >>> to console. > > >> Why can't driver plat->frequency in cadence driver initialize 100KH? > > >> plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency", 100000) > > > I'm not sure I understand. > > > The cadence driver initializes its 'plat->max_hz' from > > > "spi-max-frequency" property and defaults to 500 kHz. No problem > > > there. > > > > > > However, the problem I want to solve is if someone puts a flash chip > > > below there which has compatible != "spi-flash", they will get a hard > > > fault which is hard to debug. This is because the node is not parsed > > > because of the wrong compatible string (even if there is an > > > "spi-max-frequency" property) and thus, "sf probe" tries to continue > > > with 0 Hz. > > > > > > And this can happen easily when porting device trees from Linux as > > > there, the boards have compatible "n25q00" etc. instead of > > > "spi-flash", which is U-Boot specific (sadly). > > > > > > This patch is not required to make valid U-Boot devicetrees work, it > > > is meant to get better error handling for devicetrees ported from > > > Linux. > > > > > > An even better fix would be for U-Boot not to require the compatible = > > > "spi-flash" string but just work correctly with Linux device trees, > > > but that's not within my possibilities right now :-( > > > > Ping? This is a bug that should hit nearly everyone porting a board dts > > working in Linux to U-Boot, can we please have some kind of fix for this? > > Currently, using a dts with an spi flash chip that works in Linux may > > abort in U-Boot... > > Reviewed-by: Simon Glass <s...@chromium.org> > > Applied to u-boot-dm/master, thanks!
I hold this because, there is a discussion going on with me and Simon.k about Linux compatible "jedec,spi-nor". adding support for this binding would eventually not reproduce this issue. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
