Hi Ajay, Am 01.08.2014 09:02, schrieb Ajay kumar: > On Thu, Jul 31, 2014 at 7:52 PM, Andreas Färber wrote: >> So, with simplefb reverted in U-Boot and ... >> >> * with just the v6 applied (...~2), I get only a black screen from >> Linux, no penguins, but the backlight seems on. System comes up okay, >> ssh available, and nothing stands out in dmesg. >> >> * with the two iommu patches on top, something breaks badly, no >> backlight, no USB/network, system inaccessible. >> I.e. U-Boot had no noticeable impact on these symptoms. >> >> * with the iommu patches, but dp-controller, ps8622, panel commented >> out, I do get backlight but USB/network not working, system inaccessible. >> >> With simplefb support in U-Boot and with just v6 applied, but >> dp-controller, ps8622, panel commented out, things work as well as >> before, i.e. this series has no bad side effects. Note that I never >> claimed Ajay's series were broken, just reported that things regressed >> for me from v4, which may well be DT-related. >> >> The iommu patches interfere with my USB somehow (none or not all devices >> powered; with v4, plugging my wifi dongle led to oops but ethernet >> dongle worked, so not entirely new symptom), which is bad since my >> rootfs is on USB. The internal SDIO-connected Wifi is not enabled yet, >> so USB based network is my only alternative to a working display once we >> reach userspace. > Well, there are 2 variants here: > 1) Bootloader > 2) config > > Type of the bootloader should not matter unless its switching on > FET1 and FET6 of tps65090 for you. > > But, config can be different! > I have attached a config i used to get display with your latest > spring-bridge.v6. > Uncomment the DT nodes for DP and bridge chip and you should > be able to get display and also the login. > > I think that you have not selected all the configs needed for IOMMU to > work properly. When I deselected few IOMMU configs, I could see system > crashing when FIMD + DP path was being initialized. May be, that is why your > USB stops working. Even I have root file system on USB drive. Find attached a diff between our configs. The following stand out: * I have LPAE enabled * you don't have DMA enabled * I have CMA enabled (like in the new defconfigs) * I have the arch timer disabled (which you suggested earlier for delay) * I have more devices enabled (SPI, PWM, cpufreq, watchdog, ...) Andreas -- SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg