Thanks for the response! On Sat, Jan 23, 2021 at 2:27 AM Stefano Stabellini <sstabell...@kernel.org> wrote:
> + xen-devel, Roman, > > > On Fri, 22 Jan 2021, Jukka Kaartinen wrote: > > Hi Stefano, > > I'm Jukka Kaartinen a SW developer working on enabling hypervisors on > mobile platforms. One of our HW that we use on development is > > Raspberry Pi 4B. I wonder if you could help me a bit :). > > > > I'm trying to enable the GPU with Xen + Raspberry Pi for dom0. > https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=232323#p1797605 > > > > I got so far that GPU drivers are loaded (v3d & vc4) without errors. But > now Xen returns error when X is starting: > > (XEN) traps.c:1986:d0v1 HSR=0x93880045 pc=0x00007f97b14e70 > gva=0x7f7f817000 gpa=0x0000401315d000 > > I tried to debug what causes this and looks > like find_mmio_handler cannot find handler. > > (See more here: > https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=232323&start=25#p1801691 > ) > > > > Any ideas why the handler is not found? > > > Hi Jukka, > > I am glad to hear that you are interested in Xen on RaspberryPi :-) I > haven't tried the GPU yet, I have been using the serial only. > Roman, did you ever get the GPU working? > > > The error is a data abort error: Linux is trying to access an address > which is not mapped to dom0. The address seems to be 0x401315d000. It is > a pretty high address; I looked in device tree but couldn't spot it. > > From the HSR (the syndrom register) it looks like it is a translation > fault at EL1 on stage1. As if the Linux address mapping was wrong. > Anyone has any ideas how this could happen? Maybe a reserved-memory > misconfiguration? > I had issues with loading the driver in the first place. Apparently swiotlb is used, maybe it can cause this. I also tried to enable CMA. config.txt: dtoverlay=vc4-fkms-v3d,cma=320M@0x0-0x40000000 gpu_mem=128 That memory is very high. Success full address is for example this: 0xff841f00 (XEN) GICv2 initialization: (XEN) gic_dist_addr=00000000ff841000 (XEN) gic_cpu_addr=00000000ff842000 (XEN) gic_hyp_addr=00000000ff844000 (XEN) gic_vcpu_addr=00000000ff846000 (XEN) gic_maintenance_irq=25 > > p.s. > > While testing I found issue with Xen master branch and your > patch: xen/rpi4: implement watchdog-based reset > > > > Looks like black listing the bcm2835-pm > > @@ -37,12 +41,69 @@ static const struct dt_device_match > rpi4_blacklist_dev[] __initconst = > > * The aux peripheral also shares a page with the aux UART. > > */ > > DT_MATCH_COMPATIBLE("brcm,bcm2835-aux"), > > + /* Special device used for rebooting */ > > + DT_MATCH_COMPATIBLE("brcm,bcm2835-pm"), > > > > will prevent v3d driver to locate phandle. I think it will use the same > resource: > > pm: watchdog@7e100000 { > > compatible = "brcm,bcm2835-pm", "brcm,bcm2835-pm-wdt"; > > #power-domain-cells = <1>; > > #reset-cells = <1>; > > reg = <0x7e100000 0x114>, > > <0x7e00a000 0x24>, > > <0x7ec11000 0x20>; > > clocks = <&clocks BCM2835_CLOCK_V3D>, > > <&clocks BCM2835_CLOCK_PERI_IMAGE>, > > <&clocks BCM2835_CLOCK_H264>, > > <&clocks BCM2835_CLOCK_ISP>; > > clock-names = "v3d", "peri_image", "h264", "isp"; > > system-power-controller; > > > > }; > > Yeah, I imagine it could be possible. Can you post the error message you > are seeing from the v3d driver? This is the error: [ 0.069682] OF: /v3dbus/v3d@7ec04000: could not find phandle [ 0.074828] OF: /v3dbus/v3d@7ec04000: could not find phandle v3d driver is not loaded. -- Br, Jukka Kaartinen
