Re: [Xen-devel] [Qemu-devel] Cirrus VGA slow screen update, show blank screen last 13s or so for windows XP guest

[Ben Guthro <Ben.Guthro@xxxxxxxxxx>]

On Aug 20, 2013, at 3:45 PM, Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
 wrote:

> On Sat, Aug 17, 2013 at 09:04:29AM +0000, Gonglei (Arei) wrote:
>> Hi,
>> The fundamental reason is traditional qemu-dm and upstream qemu using a 
>> different vgabios-cirrus.bin,
>> qemu-dm is using xen-4.1.2/tools/firmware/vgabios/ 
>> VGABIOS-lgpl-latest.cirrus.bin, 
>> but upstream qemu is using qemu-1.2.2/pc-bios/vgabios-cirrus.bin
>> 
>> the pivotal patch is :
>> 
>> # HG changeset patch
>> # User Keir Fraser <keir@xxxxxxxxxxxxx>
>> # Date 1193391667 -3600
>> # Node ID d31f63db5f1e88deadc5461adda07b77c22873d7
>> # Parent  413107fa49a50e5c61ac390dc1870d8995b2a012
>> 
>> x86, hvm: Allow Cirrus VGA BIOS to clear framebuffer with minimal PIO writes.
>> 
>> Signed-off-by: Ben Guthro <bguthro@xxxxxxxxxxxxxx>
>> Signed-off-by: Gary Grebus <ggrebus@xxxxxxxxxxxxxxx>
> 
> Ben's new address is <benjamin.guthro@xxxxxxxxxx>. CC-ing him here.

FWIW, I took Gary's patch, and made it apply to unstable, at that time.
He was the primary developer, in that case.

That's how I recall it, anyhow...from 6 years ago.

I don't have Gary's new contact info.

Regards,
Ben

> 
>> 
>> diff -r 413107fa49a5 -r d31f63db5f1e tools/firmware/vgabios/clext.c
>> --- a/tools/firmware/vgabios/clext.c Fri Oct 26 10:33:12 2007 +0100
>> +++ b/tools/firmware/vgabios/clext.c Fri Oct 26 10:41:07 2007 +0100
>> @@ -1489,14 +1489,26 @@
>>   mov dx, #0x3ce
>>   out dx, ax
>>   push ax
>> -  mov cx, #0xa000
>> -  mov es, cx
>> -  xor di, di
>> +
>> +;; Windows Vista appears to be emulating this sequence as part of changing 
>> +;; screen resolution, but it generates 4096 writes per iteration.
>> +;; Instead, use a magic register sequence to write the whole bank.
>> +;;mov cx, #0xa000
>> +;;mov es, cx
>> +;;xor di, di
>> +;;mov ax, si
>> +;;mov cx, #8192
>> +;;cld
>> +;;rep
>> +;;    stosw
>>   mov ax, si
>> -  mov cx, #8192
>> -  cld
>> -  rep
>> -      stosw
>> +  shl ax, #8
>> +  mov al, #0xfe
>> +  out dx, ax        ;; Low byte of value to be written to the bank
>> +  mov ax, si
>> +  mov al, #0xff  
>> +  out dx, ax    ;; High byte and trigger the write
>> +
>>   pop ax
>>   inc ah
>>   cmp ah, bl
>> diff -r 413107fa49a5 -r d31f63db5f1e tools/ioemu/hw/cirrus_vga.c
>> --- a/tools/ioemu/hw/cirrus_vga.c    Fri Oct 26 10:33:12 2007 +0100
>> +++ b/tools/ioemu/hw/cirrus_vga.c    Fri Oct 26 10:41:07 2007 +0100
>> @@ -294,6 +294,7 @@
>> 
>> static void cirrus_bitblt_reset(CirrusVGAState *s);
>> static void cirrus_update_memory_access(CirrusVGAState *s);
>> +static void cirrus_vga_mem_writew(void *opaque, target_phys_addr_t addr, 
>> uint32_t val);
>> 
>> /***************************************
>>  *
>> @@ -1497,6 +1498,17 @@
>>     case 0x31:                       // BLT STATUS/START
>>      cirrus_write_bitblt(s, reg_value);
>>      break;
>> +
>> +    // Extension to allow BIOS to clear 16K VRAM bank in one operation
>> +    case 0xFE:
>> +    s->gr[reg_index] = reg_value;  // Lower byte of value to be written
>> +    break;
>> +    case 0xFF: {
>> +    target_phys_addr_t addr;
>> +    for (addr = 0xa0000; addr < 0xa4000; addr += 2)
>> +        cirrus_vga_mem_writew(s, addr, (reg_value << 8) | s->gr[0xFE]);
>> +    }
>> +    break;
>>     default:
>> #ifdef DEBUG_CIRRUS
>>      printf("cirrus: outport gr_index %02x, gr_value %02x\n", reg_index,
>> 
>> By replacing the vgabios-cirrus.bin, the windows XP guest screen updating is 
>> fast with upstream qemu.
>> 
>> And I test the latest vgabios-0.7a come from 
>> http://www.nongnu.org/vgabios/#DOWNLOAD
>> but the problem of blank screen remain.
>> 
>> Best Regards!
>> -Gonglei
>> 
>> 
>>> -----Original Message-----
>>> From: Gonglei (Arei)
>>> Sent: Friday, August 16, 2013 5:10 PM
>>> To: Gonglei (Arei); 'Pasi KÃrkkÃinen'
>>> Cc: 'Gerd Hoffmann'; 'Andreas FÃrber'; Hanweidong; Luonengjun;
>>> 'qemu-devel@xxxxxxxxxx'; 'xen-devel@xxxxxxxxxxxxx'; 'Anthony Liguori';
>>> Huangweidong (Hardware); 'Ian.Jackson@xxxxxxxxxxxxx'; 'Anthony Liguori';
>>> Yanqiangjun; Yangxiaowei
>>> Subject: RE: [Xen-devel] [Qemu-devel] Cirrus VGA slow screen update, show
>>> blank screen last 13s or so for windows XP guest
>>> 
>>> Hi, all
>>> I compared the traditional qemu-dm and upstream qemu,
>>> and I found the upstream qemu will create the expansion ROM at f3000000,
>>> but qemu-dm don't.
>>> the details as below (by "lspci -vnnn"):
>>> 
>>> 1) traditional qemu-dm:
>>> 00:02.0 VGA compatible controller [0300]: Cirrus Logic GD 5446 [1013:00b8]
>>> (prog-if 00 [VGA controller])
>>>     Subsystem: XenSource, Inc. Device [5853:0001]
>>>     Flags: bus master, fast devsel, latency 0, IRQ 11
>>>     Memory at f0000000 (32-bit, prefetchable) [size=32M]
>>>     Memory at f3000000 (32-bit, non-prefetchable) [size=4K]
>>>     Kernel modules: cirrusfb
>>> 
>>> 2) upstream qemu:
>>> 00:02.0 VGA compatible controller [0300]: Cirrus Logic GD 5446 [1013:00b8]
>>> (prog-if 00 [VGA controller])
>>>     Subsystem: XenSource, Inc. Device [5853:0001]
>>>     Physical Slot: 2
>>>     Flags: bus master, fast devsel, latency 0, IRQ 11
>>>     Memory at f0000000 (32-bit, prefetchable) [size=32M]
>>>     Memory at f3020000 (32-bit, non-prefetchable) [size=4K]
>>>     Expansion ROM at f3000000 [disabled] [size=64K]
>>>     Kernel modules: cirrusfb
>>> 
>>> I tried to simply delete the expansion ROM at function pci_add_option_rom,
>>> such as
>>> 
>>>  //pci_register_bar(pdev, PCI_ROM_SLOT, 0, &pdev->rom);
>>> 
>>> but the VNC viewer only can see black screen, but RDP works well.
>>> Any ideas about the cirrus's expansion ROM?
>>> Slow screen refresh has any relationship with cirrus's expansion ROM?
>>> Thank you in advanceï
>>> 
>>> BTW, I added some log in stdvga.c(xen-4.1.2/xen/arch/x86/hvm):
>>> static int stdvga_intercept_mmio(ioreq_t *p)
>>> {
>>>    struct domain *d = current->domain;
>>>    struct hvm_hw_stdvga *s = &d->arch.hvm_domain.stdvga;
>>>    int buf = 0, rc;
>>>    static int count_1 = 0;
>>>    static int count_2 = 0;
>>> 
>>>    if ( p->size > 8 )
>>>    {
>>>        gdprintk(XENLOG_WARNING, "invalid mmio size %d\n", (int)p->size);
>>>        return X86EMUL_UNHANDLEABLE;
>>>    }
>>> 
>>>    spin_lock(&s->lock);
>>> 
>>>    if ( s->stdvga && s->cache )
>>>    {
>>>        switch ( p->type )
>>>        {
>>>        case IOREQ_TYPE_COPY:
>>>            buf = mmio_move(s, p);
>>>            count_1++;
>>>            if (count_1 % 1000 == 0)
>>>                gdprintk(XENLOG_WARNING, " =uvp= enter mmio_move,
>>> count_1=%d\n", count_1);
>>>            if ( !buf )
>>>                s->cache = 0;
>>>            break;
>>>        default:
>>>            gdprintk(XENLOG_WARNING, "unsupported mmio request
>>> type:%d "
>>>                     "addr:0x%04x data:0x%04x size:%d count:%d
>>> state:%d "
>>>                     "isptr:%d dir:%d df:%d\n",
>>>                     p->type, (int)p->addr, (int)p->data, (int)p->size,
>>>                     (int)p->count, p->state,
>>>                     p->data_is_ptr, p->dir, p->df);
>>>            s->cache = 0;
>>>        }
>>>    }
>>>    else
>>>    {
>>>        buf = (p->dir == IOREQ_WRITE);
>>>        count_2++;
>>>        if (count_2 % 5000 == 0)
>>>            gdprintk(XENLOG_WARNING, " >>> vga mmio count_2=%d\n",
>>> count_2);
>>>    }
>>> 
>>>    rc = (buf && hvm_buffered_io_send(p));
>>> 
>>>    spin_unlock(&s->lock);
>>> 
>>>    return rc ? X86EMUL_OKAY : X86EMUL_UNHANDLEABLE;
>>> }
>>> 
>>> and I got the below result with upstream qemu and tranditional qemu-dm:
>>> 
>>> 1) traditional qemu-dm:
>>> (XEN) stdvga.c:152:d2 entering stdvga and caching modes
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=460000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=461000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=462000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=463000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=464000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=465000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=466000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=467000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=468000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=469000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=470000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=471000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=472000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=473000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=474000
>>> (XEN) stdvga.c:577:d2  =uvp= enter mmio_move, count_1=475000
>>> (XEN) stdvga.c:156:d2 leaving stdvga
>>> 
>>> 2) upstream qemu:
>>> (XEN) stdvga.c:152:d1 entering stdvga and caching modes
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=233000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=234000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=235000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=236000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=237000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=238000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=239000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=240000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=241000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=242000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=243000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=244000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=245000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=246000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=247000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=248000
>>> (XEN) stdvga.c:577:d1  =uvp= enter mmio_move, count_1=249000
>>> (XEN) stdvga.c:156:d1 leaving stdvga
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=8400000
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=8405000
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=8410000
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=8415000
>>>  ... ... //Omit some similar
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=12570000
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=12575000
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=12580000
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=12585000
>>> (XEN) stdvga.c:596:d1  >>> vga mmio count_2=12590000
>>> 
>>> Upstream qemu has lot's of MMIO access Memory region 0xa0000~0xc0000
>>> than traditional qemu-dm.
>>> 
>>> Best Regards!
>>> 
>>> -Gonglei
>>> 
>> _______________________________________________
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>> Xen-devel@xxxxxxxxxxxxx
>> http://lists.xen.org/xen-devel

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