Re: [Qemu-devel] [PATCH] pci: fix bridge IO/BASE

[Blue Swirl]

On Sun, Mar 4, 2012 at 09:46, Michael S. Tsirkin <address@hidden> wrote:
> commit 5caef97a16010f818ea8b950e2ee24ba876643ad introduced
> a regression: we do not make IO base/limit upper 16
> bit registers writeable, so we should report a 16 bit
> IO range type, not a 32 bit one.
> Note that PCI_PREF_RANGE_TYPE_32 is 0x0, but PCI_IO_RANGE_TYPE_32 is 0x1.
>
> In particular, this broke sparc64.
>
> Note: this just reverts to behaviour prior to the patch.
> Making PCI_IO_BASE_UPPER16 and PCI_IO_LIMIT_UPPER16
> registers writeable should, and seems to, work just as well, but
> as no system seems to actually be interested in 32 bit IO,
> let's not make unnecessary changes.
>
> Reported-by: Mark Cave-Ayland <address@hidden>
> Signed-off-by: Michael S. Tsirkin <address@hidden>
>
> Mark, can you confirm that this fixes the bug for you?

No, running
qemu-system-sparc64 -serial stdio
still shows black screen and the following on console:
OpenBIOS for Sparc64
Unhandled Exception 0x0000000000000032
PC = 0x00000000ffd19e18 NPC = 0x00000000ffd19e1c
Stopping execution

This unassigned memory exception is triggered because CMD646 IDE I/O
registers are not accessible:

(qemu) info pci
  Bus  0, device   0, function 0:
    Host bridge: PCI device 108e:a000
      id ""
  Bus  0, device   1, function 0:
    PCI bridge: PCI device 108e:5000
      BUS 0.
      secondary bus 1.
      subordinate bus 1.
      IO range [0x0000, 0x0fff]
      memory range [0x00000000, 0x000fffff]
      prefetchable memory range [0x00000000, 0x000fffff]
      id ""
  Bus  0, device   1, function 1:
    PCI bridge: PCI device 108e:5000
      BUS 0.
      secondary bus 2.
      subordinate bus 2.
      IO range [0x0000, 0x0fff]
      memory range [0x00000000, 0x000fffff]
      prefetchable memory range [0x00000000, 0x000fffff]
      id ""
  Bus  0, device   2, function 0:
    VGA controller: PCI device 1234:1111
      BAR0: 32 bit prefetchable memory at 0x00800000 [0x00ffffff].
      BAR6: 32 bit memory at 0x01000000 [0x0100ffff].
      id ""
  Bus  0, device   3, function 0:
    Bridge: PCI device 108e:1000
      BAR0: 32 bit memory at 0x02000000 [0x02ffffff].
      BAR1: 32 bit memory at 0x03000000 [0x037fffff].
      id ""
  Bus  0, device   4, function 0:
    Ethernet controller: PCI device 10ec:8029
      IRQ 0.
      BAR0: I/O at 0xffffffffffffffff [0x00fe].
      BAR6: 32 bit memory at 0x03800000 [0x0380ffff].
      id ""
  Bus  0, device   5, function 0:
    IDE controller: PCI device 1095:0646
      IRQ 1.
      BAR0: I/O at 0xffffffffffffffff [0x0006].
      BAR1: I/O at 0xffffffffffffffff [0x0002].
      BAR2: I/O at 0xffffffffffffffff [0x0006].
      BAR3: I/O at 0xffffffffffffffff [0x0002].
      BAR4: I/O at 0xffffffffffffffff [0x000e].
      id ""
(qemu) info mtree
memory
0000000000000000-7ffffffffffffffe (prio 0, RW): system
  0000000000000000-0000000007ffffff (prio 0, RW): sun4u.ram
  000001fe00000000-000001fe0000ffff (prio 0, RW): apb-config
  000001fe01000000-000001fe01ffffff (prio 0, RW): apb-pci-config
  000001fe02000000-000001fe0200ffff (prio 0, RW): apb-pci-ioport
  000001ff00000000-000001ffffffffff (prio 0, RW): pci-mmio
    000001ff00000000-000001ff000fffff (prio 1, RW): alias
pci_bridge_mem @pci_bridge_pci 0000000000000000-00000000000fffff
    000001ff00000000-000001ff000fffff (prio 1, RW): alias
pci_bridge_pref_mem @pci_bridge_pci 0000000000000000-00000000000fffff
    000001ff00000000-000001ff000fffff (prio 1, RW): alias
pci_bridge_mem @pci_bridge_pci 0000000000000000-00000000000fffff
    000001ff00000000-000001ff000fffff (prio 1, RW): alias
pci_bridge_pref_mem @pci_bridge_pci 0000000000000000-00000000000fffff
    000001ff000a0000-000001ff000affff (prio 2, RW): alias vga.chain4
@vga.vram 0000000000000000-000000000000ffff
    000001ff000a0000-000001ff000bffff (prio 1, RW): vga-lowmem
    000001ff00800000-000001ff00ffffff (prio 1, RW): vga.vram
    000001ff01000000-000001ff0100ffff (prio 1, RW): vga.rom
    000001ff02000000-000001ff02ffffff (prio 1, RW): isa-mmio
    000001ff03000000-000001ff037fffff (prio 1, RW): isa-mmio
    000001ff03800000-000001ff0380ffff (prio 1, RW): ne2000.rom
  000001fff0000000-000001fff03fffff (prio 0, R-): sun4u.prom
pci_bridge_pci
0000000000000000-7ffffffffffffffe (prio 0, RW): pci_bridge_pci
pci_bridge_pci
0000000000000000-7ffffffffffffffe (prio 0, RW): pci_bridge_pci
vga.vram
0000000000800000-0000000000ffffff (prio 1, RW): vga.vram
I/O
0000000000000000-000000000000ffff (prio 0, RW): io
  0000000000000000-0000000000000fff (prio 1, RW): alias pci_bridge_io
@pci_bridge_io 0000000000000000-0000000000000fff
  0000000000000000-0000000000000fff (prio 1, RW): alias pci_bridge_io
@pci_bridge_io 0000000000000000-0000000000000fff
  0000000000000060-0000000000000060 (prio 0, RW): i8042-data
  0000000000000064-0000000000000064 (prio 0, RW): i8042-cmd
  0000000000000074-0000000000000077 (prio 0, RW): m48t59
  00000000000001ce-00000000000001ce (prio 0, RW): alias vbe @vbe
00000000000001ce-00000000000001ce
  00000000000001d0-00000000000001d0 (prio 0, RW): alias vbe @vbe
00000000000001d0-00000000000001d0
  0000000000000378-000000000000037f (prio 0, RW): alias parallel
@parallel 0000000000000378-000000000000037f
  00000000000003b4-00000000000003b5 (prio 0, RW): alias vga @vga
00000000000003b4-00000000000003b5
  00000000000003ba-00000000000003ba (prio 0, RW): alias vga @vga
00000000000003ba-00000000000003ba
  00000000000003c0-00000000000003cf (prio 0, RW): alias vga @vga
00000000000003c0-00000000000003cf
  00000000000003d4-00000000000003d5 (prio 0, RW): alias vga @vga
00000000000003d4-00000000000003d5
  00000000000003da-00000000000003da (prio 0, RW): alias vga @vga
00000000000003da-00000000000003da
  00000000000003f1-00000000000003f5 (prio 0, RW): alias fdc @fdc
00000000000003f1-00000000000003f5
  00000000000003f7-00000000000003f7 (prio 0, RW): alias fdc @fdc
00000000000003f7-00000000000003f7
  00000000000003f8-00000000000003ff (prio 0, RW): serial
  0000000000000510-0000000000000511 (prio 0, RW): fwcfg

> ---
>  hw/pci.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/hw/pci.c b/hw/pci.c
> index fee27fc..6d08cef 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -633,8 +633,8 @@ static void pci_init_mask_bridge(PCIDevice *d)
>     memset(d->wmask + PCI_PREF_BASE_UPPER32, 0xff, 8);
>
>     /* Supported memory and i/o types */
> -    d->config[PCI_IO_BASE] |= PCI_IO_RANGE_TYPE_32;
> -    d->config[PCI_IO_LIMIT] |= PCI_IO_RANGE_TYPE_32;
> +    d->config[PCI_IO_BASE] |= PCI_IO_RANGE_TYPE_16;
> +    d->config[PCI_IO_LIMIT] |= PCI_IO_RANGE_TYPE_16;
>     pci_word_test_and_set_mask(d->config + PCI_PREF_MEMORY_BASE,
>                                PCI_PREF_RANGE_TYPE_64);
>     pci_word_test_and_set_mask(d->config + PCI_PREF_MEMORY_LIMIT,
> --
> 1.7.9.111.gf3fb0