Re: [Qemu-devel] [PATCH] sun4m: obey -vga none

Re: [Qemu-devel] [PATCH] sun4m: obey -vga none

[Philippe Mathieu-Daudé]

Hi Paolo,

On 3/19/19 3:40 PM, Paolo Bonzini wrote:
> Do not create a TCX if "-vga none" was passed on the command line.
> Remove some dead code along the way to avoid big reindentation.

Can you add:

This fixes when configuring with --without-default-devices:

  $ sparc-softmmu/qemu-system-sparc
  qemu-system-sparc: Unknown device 'SUNW,tcx' for default sysbus
  Aborted (core dumped)

  (gdb) bt
  #1  0x00007fc78d17d895 in __GI_abort () at abort.c:79
  #2  0x0000560beaf637f3 in qdev_create (bus=bus@entry=0x0,
name=name@entry=0x560beb1be36b "SUNW,tcx") at hw/core/qdev.c:131
  #3  0x0000560beaf1392d in tcx_init (vram_size=1048576, width=1024,
height=768, depth=8, irq=0x560bed1a0230, addr=1342177280) at
hw/sparc/sun4m.c:477
  #4  0x0000560beaf1392d in sun4m_hw_init (hwdef=0x560beb1be780
<sun4m_hwdefs>, machine=0x560becf65f00) at hw/sparc/sun4m.c:943
  #5  0x0000560beaf6b15b in machine_run_board_init
(machine=0x560becf65f00) at hw/core/machine.c:1030
  #6  0x0000560beae86692 in main (argc=<optimized out>, argv=<optimized
out>, envp=<optimized out>) at vl.c:4463

> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> ---
>  hw/sparc/sun4m.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/sparc/sun4m.c b/hw/sparc/sun4m.c
> index ca1e3825d5..07d126aea8 100644
> --- a/hw/sparc/sun4m.c
> +++ b/hw/sparc/sun4m.c
> @@ -850,7 +850,6 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef,
>      uint32_t initrd_size;
>      DriveInfo *fd[MAX_FD];
>      FWCfgState *fw_cfg;
> -    unsigned int num_vsimms;
>      DeviceState *dev;
>      SysBusDevice *s;
>  
> @@ -909,8 +908,7 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef,
>          error_report("Unsupported depth: %d", graphic_depth);
>          exit (1);
>      }
> -    num_vsimms = 0;
> -    if (num_vsimms == 0) {
> +    if (vga_interface_type != VGA_NONE) {
>          if (vga_interface_type == VGA_CG3) {
>              if (graphic_depth != 8) {
>                  error_report("Unsupported depth: %d", graphic_depth);
> @@ -945,7 +943,7 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef,
>          }
>      }
>  
> -    for (i = num_vsimms; i < MAX_VSIMMS; i++) {
> +    for (i = 0; i < MAX_VSIMMS; i++) {
>          /* vsimm registers probed by OBP */
>          if (hwdef->vsimm[i].reg_base) {
>              empty_slot_init(hwdef->vsimm[i].reg_base, 0x2000);
> 

Re: [Qemu-devel] What should a virtual board emulate?

[Philippe Mathieu-Daudé]

Hi Paolo,

On 3/20/19 11:35 AM, Paolo Bonzini wrote:
> On 20/03/19 11:03, Philippe Mathieu-Daudé wrote:
>>
>> -display/-vga options suffers same clarity problems than -net. Is it a
>> card device or a cable linking to a network? Here is it a card device or
>> a cable connecting a monitor display?
> 
> -display is a cable, -vga is a card ("-nic none" is a card, "-nic
> anythingelse" is a card+cable; "-net nic" is a card, "-net anythingelse"
> is a cable).
> 
>>      Mind, I'm not demanding mips-fulong2e should continue to ignore -vga;
>>      that's for its maintainer to decide.  I don't demand, I ask: what should
>>      a virtual board emulate?  What should -nodefaults do?
>>
>> IMHO -nodefaults contains soldered/mmio chipsets.
>> Whether you plug a display or not is a different story.
> 
> In principle you could also cut the copper tracks that connect the card
> to the PCI bus...

But then you have a crippled machine... We are not trying to model that.

I went back to continue a Fuloong Avocado test I started a year ago, and 
it was failing. I remember I had something working, so I bisected and 
reached this commit...

78c37d88f1b8b0b3ebcc632c458f0c3779fe2951 is the first bad commit
commit 78c37d88f1b8b0b3ebcc632c458f0c3779fe2951
Author: Paolo Bonzini <pbonzini@redhat.com>
Date:   Tue Mar 19 15:37:19 2019 +0100

     mips-fulong2e: obey -vga none

     Do not create an ATI VGA if "-vga none" was passed on the command line.

Booting PMON 1.1.2:

console: PMON2000 MIPS Initializing. Standby...
console: ERRORPC=00000000 CONFIG=00030932
console: PRID=00006302
console: DIMM read
console: 00000080
console: read memory type
console: read number of rows
console: read memory size per side
console: read blocks per ddrram
console: read number of sides
console: read width
console: DIMM SIZE=10000000
console: sdcfg=3d5043df
console: msize=10000000
console: Init SDRAM Done!
console: Sizing caches...
console: Init caches...
console: godson2 caches found
console: Init caches done, cfg = 00030932
console: Copy PMON to execute location...
console: start = 0x85000000
console: s0 = 0x3ac00000
console: a5000000
console: a5010000
console: a5020000
console: a5030000
console: a5040000
console: copy text section done.
console: Copy PMON to execute location done.
console: sp=84ffc000Uncompressing Bios........................OK,Booting 
Bios
console: FREQ
console: FREI
console: DONE
console: TTYI
console: TTYD
console: ENVI
console: MAPV
console: Mfg  0, Id 60
console: STDV
console: 80100000: heap is already above this point
console: SBDD
console: 686I
console: 0x3f8=ff
console: PPCIH
console: PCI bus 0 slot 5/0: reg 0x10 = 0x0
console: PCI bus 0 slot 5/0: reg 0x14 = 0x0
console: PCI bus 0 slot 5/0: reg 0x18 = 0x0
console: PCI bus 0 slot 5/0: reg 0x1c = 0x0
console: PCI bus 0 slot 5/0: reg 0x20 = 0x0
console: PCI bus 0 slot 5/0: reg 0x24 = 0x0
console: PCI bus 0 slot 5/1: reg 0x10 = 0xfffffff9
console: PCI bus 0 slot 5/1: reg 0x14 = 0xfffffffd
console: PCI bus 0 slot 5/1: reg 0x18 = 0xfffffff9
console: PCI bus 0 slot 5/1: reg 0x1c = 0xfffffffd
console: PCI bus 0 slot 5/1: reg 0x20 = 0xfffffff1
console: PCI bus 0 slot 5/1: reg 0x24 = 0x0
console: PCI bus 0 slot 5/2: reg 0x10 = 0x0
console: PCI bus 0 slot 5/2: reg 0x14 = 0x0
console: PCI bus 0 slot 5/2: reg 0x18 = 0x0
console: PCI bus 0 slot 5/2: reg 0x1c = 0x0
console: PCI bus 0 slot 5/2: reg 0x20 = 0xffffffe1
console: PCI bus 0 slot 5/2: reg 0x24 = 0x0
console: PCI bus 0 slot 5/3: reg 0x10 = 0x0
console: PCI bus 0 slot 5/3: reg 0x14 = 0x0
console: PCI bus 0 slot 5/3: reg 0x18 = 0x0
console: PCI bus 0 slot 5/3: reg 0x1c = 0x0
console: PCI bus 0 slot 5/3: reg 0x20 = 0xffffffe1
console: PCI bus 0 slot 5/3: reg 0x24 = 0x0
console: PCI bus 0 slot 5/4: reg 0x10 = 0x0
console: PCI bus 0 slot 5/4: reg 0x14 = 0x0
console: PCI bus 0 slot 5/4: reg 0x18 = 0x0
console: PCI bus 0 slot 5/4: reg 0x1c = 0x0
console: PCI bus 0 slot 5/4: reg 0x20 = 0x0
console: PCI bus 0 slot 5/4: reg 0x24 = 0x0
console: PCI bus 0 slot 5/5: reg 0x10 = 0x0
console: PCI bus 0 slot 5/5: reg 0x14 = 0x0
console: PCI bus 0 slot 5/5: reg 0x18 = 0x0
console: PCI bus 0 slot 5/5: reg 0x1c = 0x0
console: PCI bus 0 slot 5/5: reg 0x20 = 0x0
console: PCI bus 0 slot 5/5: reg 0x24 = 0x0
console: PCI bus 0 slot 5/6: reg 0x10 = 0x0
console: PCI bus 0 slot 5/6: reg 0x14 = 0x0
console: PCI bus 0 slot 5/6: reg 0x18 = 0x0
console: PCI bus 0 slot 5/6: reg 0x1c = 0x0
console: PCI bus 0 slot 5/6: reg 0x20 = 0x0
console: PCI bus 0 slot 5/6: reg 0x24 = 0x0
console: PCIS
console: PCIR
console: PCIW
console: NETI
console: RTCL
console: PCID
console: VGAI
console: Default MODE_ID 2
console: starting radeon init...
^
Current QEMU is stuck here.

Before it would continue:

console: iobase=bfd0a100,mmbase=b5050000
console: mc_status=5
console: mc_status=5
console: mc_status=5
console: mc_status=5
console: ppll_div_3 = 301f4
console: Wrote: 0x00000043 0x000301f4 0x00000000 (0x00000000)
console: Wrote: rd=67, fd=500, pd=3
console: VCLK_ECP_CNTL = 000000C3
console: radeon init done
console: FRBI
console: cfb_console init,fb=b4000000
console: Video: Drawing the logo ...
console: CONSOLE_SIZE 450560HSTI
...

Since:

1/ the Radeon chip is soldered on the motherboard,

2/ the default BIOS expects the Radeon chip to be
    unconditionally present,

I insist this patch is incorrect for the particular case of the 
Fuloong2e board. I plan to revert it when I post the test.

BTW I'm not using --nodefault, I'm running default ./configure:

qemu-system-mips64el -M fulong2e -bios pmon_2e.bin \
-display none -vga none -serial stdio

Regards,

Phil.

Re: [Qemu-devel] What should a virtual board emulate?

[BALATON Zoltan]

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On Sat, 4 Jan 2020, Philippe Mathieu-Daudé wrote:
> I insist this patch is incorrect for the particular case of the Fuloong2e 
> board. I plan to revert it when I post the test.

I can only repeat my comment from when it last came up:

On Wed, 20 Mar 2019, BALATON Zoltan wrote:
> Thanks, I did not know about this variable. Although the real hardware 
> has the GPU soldered on the mainboard it makes sense to allow it to be 
> disabled in QEMU especially at this stage when Linux kernel has some 
> problem with it so this is a good idea.

I think the option is useful to boot Linux now until we improve rv100 
emulation enough to work with the Linux DRM driver so either way you'll 
have a problem: with -vga none not disabling soldered chip you can't boot 
normal Linux CDs without patching them, with -vga none obeyed you can't 
use PMON. But since PMON is not bundled in QEMU (we don't have the source 
of the actual board firmware, only a binary) it may be less of a problem 
than Linux install CDs not working. After install you could change Linux 
to use radeon framebuffer driver which probably works better. (Although 
I'm not sure if anyone actually tried to do that.)

But I don't really mind either way, go with what you prefer. I only care 
about the chip emulations used by this board not going away as I plan to 
use them for pegasos2 emulation but not the fulong board itself apart from 
using it for cross checking changes. I know about one problem with the 
via-ide part that I could reproduce with both:

https://osdn.net/projects/qmiga/ticket/38949

but I'm still not sure it's not missing irq emulation in my Marvel 
Discovery II emulation that's causing problem on pegasos2.

> Reviewed-by: BALATON Zoltan <balaton@eik.bme.hu>
> 
> When changing it you could also replace the -1 in pci_create with 
> PCI_DEVFN(FULONG2E_ATI_SLOT, 0) to match the address the board has or 
> should that be a separate patch?

Looks like this above comment was not considered last time, maybe if you 
change it now this could be fixed as well.

Regards,
BALATON Zoltan

Re: [Qemu-devel] What should a virtual board emulate?

[Gerd Hoffmann]

  Hi,

> 78c37d88f1b8b0b3ebcc632c458f0c3779fe2951 is the first bad commit
> commit 78c37d88f1b8b0b3ebcc632c458f0c3779fe2951
> Author: Paolo Bonzini <pbonzini@redhat.com>
> Date:   Tue Mar 19 15:37:19 2019 +0100
> 
>     mips-fulong2e: obey -vga none
> 
>     Do not create an ATI VGA if "-vga none" was passed on the command line.

> 1/ the Radeon chip is soldered on the motherboard,
> 
> 2/ the default BIOS expects the Radeon chip to be
>    unconditionally present,
> 
> I insist this patch is incorrect for the particular case of the Fuloong2e
> board. I plan to revert it when I post the test.

Yep.  IMHO devices which you can't unplug on the physical board should
be present even with "qemu -nodefaults".

cheers,
  Gerd

Re: [Qemu-devel] What should a virtual board emulate?

[Aleksandar Markovic]

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7:45 AM Pon, 06.01.2020. Gerd Hoffmann <kraxel@redhat.com> је написао/ла:
>
>   Hi,
>
> > 78c37d88f1b8b0b3ebcc632c458f0c3779fe2951 is the first bad commit
> > commit 78c37d88f1b8b0b3ebcc632c458f0c3779fe2951
> > Author: Paolo Bonzini <pbonzini@redhat.com>
> > Date:   Tue Mar 19 15:37:19 2019 +0100
> >
> >     mips-fulong2e: obey -vga none
> >
> >     Do not create an ATI VGA if "-vga none" was passed on the command
line.
>
> > 1/ the Radeon chip is soldered on the motherboard,
> >
> > 2/ the default BIOS expects the Radeon chip to be
> >    unconditionally present,
> >
> > I insist this patch is incorrect for the particular case of the
Fuloong2e
> > board. I plan to revert it when I post the test.
>
> Yep.  IMHO devices which you can't unplug on the physical board should
> be present even with "qemu -nodefaults".
>

I have to agree with Philippe's approach. That is not to say that Zoltan's
efforts are not appreciated. Just that the patch in question that broke
Foolong scenario didn't fit quite well, however some other its
reincarnation may have better destiny.

Sincerely,
Aleksandar

> cheers,
>   Gerd
>
>

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Re: [Qemu-devel] What should a virtual board emulate?

[Aleksandar Markovic]

[-- Attachment #1: Type: text/plain, Size: 1582 bytes --]

8:42 PM Pet, 10.01.2020. Aleksandar Markovic <aleksandar.m.mail@gmail.com>
је написао/ла:
>
> 7:45 AM Pon, 06.01.2020. Gerd Hoffmann <kraxel@redhat.com> је написао/ла:
> >
> >   Hi,
> >
> > > 78c37d88f1b8b0b3ebcc632c458f0c3779fe2951 is the first bad commit
> > > commit 78c37d88f1b8b0b3ebcc632c458f0c3779fe2951
> > > Author: Paolo Bonzini <pbonzini@redhat.com>
> > > Date:   Tue Mar 19 15:37:19 2019 +0100
> > >
> > >     mips-fulong2e: obey -vga none
> > >
> > >     Do not create an ATI VGA if "-vga none" was passed on the command
line.
> >
> > > 1/ the Radeon chip is soldered on the motherboard,
> > >
> > > 2/ the default BIOS expects the Radeon chip to be
> > >    unconditionally present,
> > >
> > > I insist this patch is incorrect for the particular case of the
Fuloong2e
> > > board. I plan to revert it when I post the test.
> >
> > Yep.  IMHO devices which you can't unplug on the physical board should
> > be present even with "qemu -nodefaults".
> >
>
> I have to agree with Philippe's approach. That is not to say that
Zoltan's efforts are not appreciated.

I meant to say also Paolo's. But, I didn't mean to fingerpoint. It is quite
normal that from time to time, a well-intended change may actually produce
unexpected breaking. All is well, no bad feelings at all.

Yours,
Aleksandar

Just that the patch in question that broke Foolong scenario didn't fit
quite well, however some other its reincarnation may have better destiny.
>
> Sincerely,
> Aleksandar
>
> > cheers,
> >   Gerd
> >
> >

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Re: [Qemu-devel] What should a virtual board emulate?

[Paolo Bonzini]

On 04/01/20 22:16, Philippe Mathieu-Daudé wrote:
> 1/ the Radeon chip is soldered on the motherboard,
> 
> 2/ the default BIOS expects the Radeon chip to be
>    unconditionally present,
> 
> I insist this patch is incorrect for the particular case of the
> Fuloong2e board. I plan to revert it when I post the test.
> 
> BTW I'm not using --nodefault, I'm running default ./configure:
> 
> qemu-system-mips64el -M fulong2e -bios pmon_2e.bin \
> -display none -vga none -serial stdio

But if you're not specifying -nodefaults, why are you specifying a
configuration that your BIOS does not support?  You should just remove
-vga none and leave in -display none.

Paolo

Re: [Qemu-devel] What should a virtual board emulate?

[Philippe Mathieu-Daudé]

On 1/18/20 9:46 PM, Paolo Bonzini wrote:
> On 04/01/20 22:16, Philippe Mathieu-Daudé wrote:
>> 1/ the Radeon chip is soldered on the motherboard,
>>
>> 2/ the default BIOS expects the Radeon chip to be
>>    unconditionally present,
>>
>> I insist this patch is incorrect for the particular case of the
>> Fuloong2e board. I plan to revert it when I post the test.
>>
>> BTW I'm not using --nodefault, I'm running default ./configure:
>>
>> qemu-system-mips64el -M fulong2e -bios pmon_2e.bin \
>> -display none -vga none -serial stdio
> 
> But if you're not specifying -nodefaults, why are you specifying a
> configuration that your BIOS does not support?  You should just remove
> -vga none and leave in -display none.

OK, with this information I searched what enforcing -vga none, with:

$ git grep -- -vga.*none python/
python/qemu/machine.py:232:        args = ['-display', 'none', '-vga',
'none']

Context:

 61 class QEMUMachine(object):
...
230
231     def _base_args(self):
232         args = ['-display', 'none', '-vga', 'none']
...
290     def launch(self):
301         try:
302             self._launch()
...
314     def _launch(self):
315         """
316         Launch the VM and establish a QMP connection
317         """
318         devnull = open(os.path.devnull, 'rb')
319         self._pre_launch()
320         self._qemu_full_args = (self._wrapper + [self._binary] +
321                                 self._base_args() + self._args)

Except the refactors moving this code, the original commit is:

$ git show 0fd05e8dd1e
commit 0fd05e8dd1ee7ae143fba3d6bcc6abe3fbeaeb34
Author: Paolo Bonzini <pbonzini@redhat.com>
Date:   Wed Jun 6 16:23:27 2012 +0200

    qemu-iotests: start vms in qtest mode

    This way, they will not execute any VM code at all.  However, right now
    the cancellation test is "relying" on being slowed down by TCG executing
    BIOS code.  So, change the timeouts.

    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
    Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index e27b40e289..e05b1d640b 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -54,7 +54,9 @@ class VM(object):
         self._qemu_log_path = os.path.join(test_dir, 'qemu-log.%d' %
os.getpid())
         self._args = qemu_args + ['-chardev',
                      'socket,id=mon,path=' + self._monitor_path,
-                     '-mon', 'chardev=mon,mode=control', '-nographic']
+                     '-mon', 'chardev=mon,mode=control',
+                     '-qtest', 'stdio', '-machine', 'accel=qtest',
+                     '-display', 'none', '-vga', 'none']
         self._num_drives = 0

     def add_drive(self, path, opts=''):

diff --git a/tests/qemu-iotests/030 b/tests/qemu-iotests/030
index 4ab7d62961..cc671dd7aa 100755
--- a/tests/qemu-iotests/030
+++ b/tests/qemu-iotests/030
@@ -147,7 +147,7 @@ class TestStreamStop(ImageStreamingTestCase):
         result = self.vm.qmp('block-stream', device='drive0')
         self.assert_qmp(result, 'return', {})

-        time.sleep(1)
+        time.sleep(0.1)
         events = self.vm.get_qmp_events(wait=False)
         self.assertEqual(events, [], 'unexpected QMP event: %s' % events)

So IIUC we need to rework a bit the defaults of QEMUMachine::base_args.

Re: [Qemu-devel] What should a virtual board emulate?

[Markus Armbruster]

Paolo Bonzini <pbonzini@redhat.com> writes:

> On 04/01/20 22:16, Philippe Mathieu-Daudé wrote:
>> 1/ the Radeon chip is soldered on the motherboard,
>> 
>> 2/ the default BIOS expects the Radeon chip to be
>>    unconditionally present,
>> 
>> I insist this patch is incorrect for the particular case of the
>> Fuloong2e board. I plan to revert it when I post the test.
>> 
>> BTW I'm not using --nodefault, I'm running default ./configure:
>> 
>> qemu-system-mips64el -M fulong2e -bios pmon_2e.bin \
>> -display none -vga none -serial stdio
>
> But if you're not specifying -nodefaults, why are you specifying a
> configuration that your BIOS does not support?  You should just remove
> -vga none and leave in -display none.

Is there any use for -vga none with this machine?  If no, then rejecting
it cleanly would be nicer than having the machine hang.

Re: [Qemu-devel] What should a virtual board emulate?

[BALATON Zoltan]

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On Tue, 21 Jan 2020, Markus Armbruster wrote:
> Paolo Bonzini <pbonzini@redhat.com> writes:
>
>> On 04/01/20 22:16, Philippe Mathieu-Daudé wrote:
>>> 1/ the Radeon chip is soldered on the motherboard,
>>>
>>> 2/ the default BIOS expects the Radeon chip to be
>>>    unconditionally present,
>>>
>>> I insist this patch is incorrect for the particular case of the
>>> Fuloong2e board. I plan to revert it when I post the test.
>>>
>>> BTW I'm not using --nodefault, I'm running default ./configure:
>>>
>>> qemu-system-mips64el -M fulong2e -bios pmon_2e.bin \
>>> -display none -vga none -serial stdio
>>
>> But if you're not specifying -nodefaults, why are you specifying a
>> configuration that your BIOS does not support?  You should just remove
>> -vga none and leave in -display none.
>
> Is there any use for -vga none with this machine?  If no, then rejecting
> it cleanly would be nicer than having the machine hang.

https://lists.nongnu.org/archive/html/qemu-devel/2020-01/msg00330.html

Regards,
BALATON Zoltan