Myles Watson wrote:
Yes. qemu 0.9.1 works with v2+OpenBIOS and v3+OpenBIOS, but the latest qemu doesn't. The latest qemu works with v2 or v3 +OpenBIOS r186, so it looks like an interaction between OpenBIOS and qemu.
HTH, Myles
Okay, I think I found out what is happening. With coreboot-v3 and OpenBIOS SVN then the base address for I/O devices is set to 0x400 which causes subsequent hardware to be mapped higher. The backtrace on the hw_error() line shows this:
Breakpoint 1, register_ioport_write (start=1296, length=1, size=1, func=0x42b105 <ne2000_asic_ioport_write>, opaque=0xc9abb8) at /home/build/src/qemu/trunk/vl.c:392 392 hw_error("register_ioport_write: invalid opaque: (start 0x%x, length 0x%x, address 0x%x)", start, length, i); (gdb) print/x start $1 = 0x510 (gdb) bt #0 register_ioport_write (start=1296, length=1, size=1, func=0x42b105 <ne2000_asic_ioport_write>, opaque=0xc9abb8) at /home/build/src/qemu/trunk/vl.c:392 #1 0x000000000042bc6b in ne2000_map (pci_dev=0xc9a990, region_num=0, addr=1280, size=256, type=1) at /home/build/src/qemu/trunk/hw/ne2000.c:771 #2 0x0000000000414548 in pci_update_mappings (d=0xc9a990) at /home/build/src/qemu/trunk/hw/pci.c:301 #3 0x0000000000414706 in pci_default_write_config (d=0xc9a990, address=16, val=1281, len=4) at /home/build/src/qemu/trunk/hw/pci.c:362 #4 0x00000000004148d7 in pci_data_write (opaque=0xc281c0, addr=2147489808, val=1281, len=4) at /home/build/src/qemu/trunk/hw/pci.c:467 #5 0x0000000000483e31 in pci_host_data_writel (opaque=0xc281a0, addr=3324, val=1281) at /home/build/src/qemu/trunk/hw/pci_host.h:74 #6 0x0000000000406818 in ioport_write (index=2, address=3324, data=1281) at /home/build/src/qemu/trunk/vl.c:298 #7 0x0000000000406c0d in cpu_outl (env=0xc10650, addr=3324, val=1281) at /home/build/src/qemu/trunk/vl.c:438 #8 0x00000000005248fe in helper_outl (port=3324, data=1281) at /home/build/src/qemu/trunk/target-i386/op_helper.c:582 #9 0x0000000040e5d11c in ?? () #10 0x00000000000000f4 in ?? () #11 0x0000000006e64a20 in ?? () #12 0x0000000006f687ab in ?? () #13 0x0000000040e5ce30 in ?? () #14 0x0000000040e603c8 in ?? () #15 0x0000000008000000 in ?? () #16 0x00007fff4ef701b0 in ?? () #17 0x00000000004fcd9c in tb_set_jmp_target (tb=0x406670, n=0, addr=2361183241434822607) at ../exec-all.h:240 #18 0x000000000040c64f in main_loop () at /home/build/src/qemu/trunk/vl.c:3737 #19 0x000000000040f772 in main (argc=6, argv=0x7fff4ef70bf8, envp=0x7fff4ef70c30) at /home/build/src/qemu/trunk/vl.c:5712
So in other words, with current OpenBIOS SVN the I/O space for the network card requires more than 0x110 bytes from 0x400 and hence when qemu tries to map I/O address 0x510 (which is already mapped to the BIOS I/O port), qemu reports the error and panics.
My quick fix was to apply the following patch to openbios in order to raise the io_base further from 0x400 to 0x520 so that no devices appear below the BIOS_IO_PORT address of 0x510:
--- drivers/pci.c (revision 428) +++ drivers/pci.c (working copy) @@ -762,7 +762,7 @@ mem_base = arch->mem_base; /* I/O ports under 0x400 are used by devices mapped at fixed location. */ - io_base = arch->io_base + 0x400; + io_base = arch->io_base + 0x520; path = strdup(""); for (bus = 0; bus<0x100; bus++) { ob_scan_pci_bus(bus, &mem_base, &io_base, &path);
With this patch applied, I am pleased to report that qemu can successfully boot openbios once again. Can anyone with more knowledge comment on whether this is an adequate solution or not?
ATB,
Mark.