Hi York, Thank you for your suggestion. I sent out v3 patch which is backward-compatible. Please check.
Thanks a lot. Best regards, Yangbo Lu > -----Original Message----- > From: York Sun > Sent: 2017年12月1日 1:59 > To: Y.b. Lu <yangbo...@nxp.com>; u-boot@lists.denx.de > Cc: Xiaobo Xie <xiaobo....@nxp.com> > Subject: Re: [v2] armv8: ls1012a: enable/disable eSDHC1 through hwconfig for > RDB > > On 11/29/2017 08:44 PM, Y.b. Lu wrote: > > Hi York, > > > > I copied hardware team Kinjalk's explain here. > > > > "Enabling SDHC2 on ‘00’ is not correct on revision D and later boards as the > sd wifi is not on there on these revs. > > The IO expander was designed to override the dip switch values. So, the DIP > switch values are driven through low strength drivers. The I2C reads of DIP > switch settings may not be correct and reliable as the noise margin is very > low. > If the IO expander is driving CFG than the situation is different and reads > will > always be reliable." > > > > It seemed ls1012ardb RevD reworked the SDHC2 circuit. The SDIO wifi device > was removed and I2C reading of DIP switch setting was not reliable. > > This changes is causing many kernel error messages on RevD boards. > > "mmc1: Controller never released inhibit bit(s)." > > It's safe to disable SDHC2 in default and enable it manually when hardware > configuration(DIP switch) is correct for SDHC2 since software doesn’t have > way to check. > > > > Do you think this should be fixed by hardware? If so, I will try to suggest > > that. > > Yangbo, > > If the hardware can be fixed to operate the same way, please push for a fix. > If > rev D board (and later) removes the feature to read DIP switches, and you can > make the code backward-compatible, then we can accept this change. > > Your change is to use hwconfig to determine if eSDHC1 is available. This will > cause all previous boards losing the ability to automatically select eSDHC1. > Is > that acceptable to existing users, and clearly documented? > > York _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
