docs/specs/standard-vga: Convert to rST

Convert docs/specs/standard-vga.txt to rST format.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230927151205.70930-6-peter.maydell@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
This commit is contained in:
Peter Maydell 2023-09-27 16:12:02 +01:00
parent 945f3fd4e4
commit 68ed96bebf
6 changed files with 98 additions and 83 deletions

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@ -2468,6 +2468,7 @@ F: hw/display/vga*
F: hw/display/bochs-display.c
F: include/hw/display/vga.h
F: include/hw/display/bochs-vbe.h
F: docs/specs/standard-vga.rst
ramfb
M: Gerd Hoffmann <kraxel@redhat.com>

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@ -28,3 +28,4 @@ guest hardware that is specific to QEMU.
edu
ivshmem-spec
pvpanic
standard-vga

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@ -0,0 +1,94 @@
QEMU Standard VGA
=================
Exists in two variants, for isa and pci.
command line switches:
``-vga std``
picks isa for -M isapc, otherwise pci
``-device VGA``
pci variant
``-device isa-vga``
isa variant
``-device secondary-vga``
legacy-free pci variant
PCI spec
--------
Applies to the pci variant only for obvious reasons.
PCI ID
``1234:1111``
PCI Region 0
Framebuffer memory, 16 MB in size (by default).
Size is tunable via vga_mem_mb property.
PCI Region 1
Reserved (so we have the option to make the framebuffer bar 64bit).
PCI Region 2
MMIO bar, 4096 bytes in size (QEMU 1.3+)
PCI ROM Region
Holds the vgabios (QEMU 0.14+).
The legacy-free variant has no ROM and has ``PCI_CLASS_DISPLAY_OTHER``
instead of ``PCI_CLASS_DISPLAY_VGA``.
IO ports used
-------------
Doesn't apply to the legacy-free pci variant, use the MMIO bar instead.
``03c0 - 03df``
standard vga ports
``01ce``
bochs vbe interface index port
``01cf``
bochs vbe interface data port (x86 only)
``01d0``
bochs vbe interface data port
Memory regions used
-------------------
``0xe0000000``
Framebuffer memory, isa variant only.
The pci variant used to mirror the framebuffer bar here, QEMU 0.14+
stops doing that (except when in ``-M pc-$old`` compat mode).
MMIO area spec
--------------
Likewise applies to the pci variant only for obvious reasons.
``0000 - 03ff``
edid data blob.
``0400 - 041f``
vga ioports (``0x3c0`` to ``0x3df``), remapped 1:1. Word access
is supported, bytes are written in little endian order (aka index
port first), so indexed registers can be updated with a single
mmio write (and thus only one vmexit).
``0500 - 0515``
bochs dispi interface registers, mapped flat without index/data ports.
Use ``(index << 1)`` as offset for (16bit) register access.
``0600 - 0607``
QEMU extended registers. QEMU 2.2+ only.
The pci revision is 2 (or greater) when these registers are present.
The registers are 32bit.
``0600``
QEMU extended register region size, in bytes.
``0604``
framebuffer endianness register.
- ``0xbebebebe`` indicates big endian.
- ``0x1e1e1e1e`` indicates little endian.

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@ -1,81 +0,0 @@
QEMU Standard VGA
=================
Exists in two variants, for isa and pci.
command line switches:
-vga std [ picks isa for -M isapc, otherwise pci ]
-device VGA [ pci variant ]
-device isa-vga [ isa variant ]
-device secondary-vga [ legacy-free pci variant ]
PCI spec
--------
Applies to the pci variant only for obvious reasons.
PCI ID: 1234:1111
PCI Region 0:
Framebuffer memory, 16 MB in size (by default).
Size is tunable via vga_mem_mb property.
PCI Region 1:
Reserved (so we have the option to make the framebuffer bar 64bit).
PCI Region 2:
MMIO bar, 4096 bytes in size (qemu 1.3+)
PCI ROM Region:
Holds the vgabios (qemu 0.14+).
The legacy-free variant has no ROM and has PCI_CLASS_DISPLAY_OTHER
instead of PCI_CLASS_DISPLAY_VGA.
IO ports used
-------------
Doesn't apply to the legacy-free pci variant, use the MMIO bar instead.
03c0 - 03df : standard vga ports
01ce : bochs vbe interface index port
01cf : bochs vbe interface data port (x86 only)
01d0 : bochs vbe interface data port
Memory regions used
-------------------
0xe0000000 : Framebuffer memory, isa variant only.
The pci variant used to mirror the framebuffer bar here, qemu 0.14+
stops doing that (except when in -M pc-$old compat mode).
MMIO area spec
--------------
Likewise applies to the pci variant only for obvious reasons.
0000 - 03ff : edid data blob.
0400 - 041f : vga ioports (0x3c0 -> 0x3df), remapped 1:1.
word access is supported, bytes are written
in little endia order (aka index port first),
so indexed registers can be updated with a
single mmio write (and thus only one vmexit).
0500 - 0515 : bochs dispi interface registers, mapped flat
without index/data ports. Use (index << 1)
as offset for (16bit) register access.
0600 - 0607 : qemu extended registers. qemu 2.2+ only.
The pci revision is 2 (or greater) when
these registers are present. The registers
are 32bit.
0600 : qemu extended register region size, in bytes.
0604 : framebuffer endianness register.
- 0xbebebebe indicates big endian.
- 0x1e1e1e1e indicates little endian.

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@ -1,7 +1,7 @@
/*
* QEMU ISA VGA Emulator.
*
* see docs/specs/standard-vga.txt for virtual hardware specs.
* see docs/specs/standard-vga.rst for virtual hardware specs.
*
* Copyright (c) 2003 Fabrice Bellard
*

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@ -1,7 +1,7 @@
/*
* QEMU PCI VGA Emulator.
*
* see docs/specs/standard-vga.txt for virtual hardware specs.
* see docs/specs/standard-vga.rst for virtual hardware specs.
*
* Copyright (c) 2003 Fabrice Bellard
*