[OpenBIOS] [PATCH] vga.fs: add support for QEMU PCI MMIO register access

[G 3]

On Jun 18, 2017, at 2:50 AM, Mark Cave-Ayland wrote:

> On 10/06/17 14:25, Mark Cave-Ayland wrote:
>
>> Currently the driver works by using the legacy VGA ioports for  
>> programming
>> the display. However this makes it much harder to configure e.g.  
>> multiple
>> displays or VGA devices behind multiple PCI bridges.
>>
>> If building for QEMU, default to using the QEMU PCI MMIO registers  
>> to program
>> the display.
>>
>> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland at ilande.co.uk>
>> ---
>>  drivers/vga.fs |   85 +++++++++++++++++++++++++++++++++++++++++++ 
>> +------------
>>  1 file changed, 68 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/vga.fs b/drivers/vga.fs
>> index cbfa46c..d39b062 100644
>> --- a/drivers/vga.fs
>> +++ b/drivers/vga.fs
>> @@ -47,6 +47,22 @@ fcode-version3
>>  : ioc! ioc!-xt execute ;
>>  : iow! iow!-xt execute ;
>>
>> +" le-w!" (find-xt) value le-w!-xt
>> +
>> +: le-w! le-w!-xt execute ;
>> +
>> +\
>> +\ PCI
>> +\
>> +
>> +" pci-bar>pci-addr" (find-xt) value pci-bar>pci-addr-xt
>> +: pci-bar>pci-addr pci-bar>pci-addr-xt execute ;
>> +
>> +h# 10 constant cfg-bar0    \ Framebuffer BAR
>> +h# 18 constant cfg-bar2    \ QEMU MMIO ioport BAR
>> +-1 value fb-addr
>> +-1 value mmio-addr
>> +
>>  \
>>  \ VGA registers
>>  \
>> @@ -55,12 +71,22 @@ h# 3c0 constant vga-addr
>>  h# 3c8 constant dac-write-addr
>>  h# 3c9 constant dac-data-addr
>>
>> +defer vga-ioc!
>> +
>> +: vga-legacy-ioc!  ( val addr )
>> +  ioc!
>> +;
>> +
>> +: vga-mmio-ioc!  ( val addr )
>> +  h# 3c0 - h# 400 + mmio-addr + c!
>> +;
>> +
>>  : vga-color!  ( r g b index -- )
>>    \ Set the VGA colour registers
>> -  dac-write-addr ioc! rot
>> -  2 >> dac-data-addr ioc! swap
>> -  2 >> dac-data-addr ioc!
>> -  2 >> dac-data-addr ioc!
>> +  dac-write-addr vga-ioc! rot
>> +  2 >> dac-data-addr vga-ioc! swap
>> +  2 >> dac-data-addr vga-ioc!
>> +  2 >> dac-data-addr vga-ioc!
>>  ;
>>
>>  \
>> @@ -86,17 +112,23 @@ h# 1 constant VBE_DISPI_ENABLED
>>  \ Bochs VBE register writes
>>  \
>>
>> -: vbe-iow!  ( val addr -- )
>> +defer vbe-iow!
>> +
>> +: vbe-legacy-iow!  ( val addr -- )
>>    h# 1ce iow!
>>    h# 1d0 iow!
>>  ;
>>
>> +: vbe-mmio-iow!  ( val addr -- )
>> +  1 lshift h# 500 + mmio-addr + cr .s cr le-w!
>> +;
>> +
>>  \
>>  \ Initialise Bochs VBE mode
>>  \
>>
>>  : vbe-init  ( -- )
>> -  h# 0 vga-addr ioc!    \ Enable blanking
>> +  h# 0 vga-addr vga-ioc!    \ Enable blanking
>>    VBE_DISPI_DISABLED VBE_DISPI_INDEX_ENABLE vbe-iow!
>>    h# 0 VBE_DISPI_INDEX_X_OFFSET vbe-iow!
>>    h# 0 VBE_DISPI_INDEX_Y_OFFSET vbe-iow!
>> @@ -104,20 +136,14 @@ h# 1 constant VBE_DISPI_ENABLED
>>    openbios-video-height VBE_DISPI_INDEX_YRES vbe-iow!
>>    depth-bits VBE_DISPI_INDEX_BPP vbe-iow!
>>    VBE_DISPI_ENABLED VBE_DISPI_INDEX_ENABLE vbe-iow!
>> -  h# 0 vga-addr ioc!
>> -  h# 20 vga-addr ioc!   \ Disable blanking
>> +  h# 0 vga-addr vga-ioc!
>> +  h# 20 vga-addr vga-ioc!   \ Disable blanking
>>  ;
>>
>>  \
>> -\ PCI
>> +\ PCI BAR mapping
>>  \
>>
>> -" pci-bar>pci-addr" (find-xt) value pci-bar>pci-addr-xt
>> -: pci-bar>pci-addr pci-bar>pci-addr-xt execute ;
>> -
>> -h# 10 constant cfg-bar0    \ Framebuffer BAR
>> --1 value fb-addr
>> -
>>  : map-fb ( -- )
>>    cfg-bar0 pci-bar>pci-addr if   \ ( pci-addr.lo pci-addr.mid pci- 
>> addr.hi size )
>>      " pci-map-in" $call-parent
>> @@ -125,6 +151,32 @@ h# 10 constant cfg-bar0    \ Framebuffer BAR
>>    then
>>  ;
>>
>> +: map-mmio ( -- )
>> +  cfg-bar2 pci-bar>pci-addr if   \ ( pci-addr.lo pci-addr.mid pci- 
>> addr.hi size )
>> +    " pci-map-in" $call-parent
>> +    to mmio-addr
>> +  then
>> +;
>> +
>> +\
>> +\ Legacy IO port or QEMU MMIO accesses
>> +\
>> +\ legacy: use standard VGA ioport registers
>> +\ MMIO: use QEMU PCI MMIO VGA registers
>> +\
>> +\ If building for QEMU, default to MMIO access since it allows
>> +\ programming of the VGA card regardless of its position in the
>> +\ PCI topology
>> +\
>> +
>> +[IFDEF] CONFIG_QEMU
>> +['] vga-mmio-ioc! to vga-ioc!
>> +['] vbe-mmio-iow! to vbe-iow!
>> +[ELSE]
>> +['] vga-legacy-ioc! to vga-ioc!
>> +['] vbe-legacy-iow! to vbe-iow!
>> +[THEN]
>> +
>>  \
>>  \ Publically visible words
>>  \
>> @@ -181,6 +233,7 @@ headerless
>>  \
>>
>>  : qemu-vga-driver-install ( -- )
>> +  map-mmio vbe-init
>>    fb-addr -1 = if
>>      map-fb fb-addr to frame-buffer-adr
>>      default-font set-font
>> @@ -193,8 +246,6 @@ headerless
>>  ;
>>
>>  : qemu-vga-driver-init
>> -
>> -  vbe-init
>>    openbios-video-width encode-int " width" property
>>    openbios-video-height encode-int " height" property
>>    depth-bits encode-int " depth" property
>>
>
> This passes all my local tests so I've applied it to master.

If the user isn't satisfied with the default VGA resolutions, is  
there a way to add a set?