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Update README
Updates the copyright date, and replaces the rather out-of-date 2D documentation with a link to the updated 2D and 3D docs on Source Forge.
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committed by
Philip Langdale
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553
README
553
README
@@ -1,555 +1,12 @@
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Copyright (C) 1999-2002 VMware, Inc.
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Copyright (C) 1999-2009 VMware, Inc.
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All Rights Reserved
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The code here may be used/distributed under the terms of the standard
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XFree86 license.
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Documentation on the VMware SVGA Device programming model
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has been updated and expanded, and it now lives at:
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VMware SVGA Device Interface and Programming Model
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--------------------------------------------------
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http://vmware-svga.sourceforge.net/
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Include Files
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-------------
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svga_reg.h
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SVGA register definitions, SVGA capabilities, and FIFO command definitions.
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svga_limits.h
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Included by svga_reg.h, defines maximum frame buffer and memory region
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sizes.
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svga_modes.h
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A list of default display modes that are built into the driver.
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svga_overlay.h
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A list of definitions required for Xv extension support. Included by vmwarevideo.c
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svga_escape.h
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A list of definitions for the SVGA Escape commands.
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guest_os.h
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Values for the GUEST_ID register.
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vm_basic_types.h
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Common type definitions.
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vm_device_version.h
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PCI vendor ID's and related information.
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vmwarectrl.h
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vmwarectrlproto.h
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The definitions of the VMWARECTRL protocol extension.
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Programming the VMware SVGA Device
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----------------------------------
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1. Reading/writing a register:
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The SVGA registers are addressed by an index/value pair of 32 bit
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registers in the IO address space.
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The 0710 VMware SVGA chipset (PCI device ID PCI_DEVICE_ID_VMWARE_SVGA) has
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its index and value ports hardcoded at:
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index: SVGA_LEGACY_BASE_PORT + 4 * SVGA_INDEX_PORT
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value: SVGA_LEGACY_BASE_PORT + 4 * SVGA_VALUE_PORT
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The 0405 VMware SVGA chipset (PCI device ID PCI_DEVICE_ID_VMWARE_SVGA2)
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determines its index and value ports as a function of the first base
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address register in its PCI configuration space as:
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index: <Base Address Register 0> + SVGA_INDEX_PORT
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value: <Base Address Register 0> + SVGA_VALUE_PORT
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To read a register:
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Set the index port to the index of the register, using a dword OUT
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Do a dword IN from the value port
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To write a register:
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Set the index port to the index of the register, using a dword OUT
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Do a dword OUT to the value port
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Example, setting the width to 1024:
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mov eax, SVGA_REG_WIDTH
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mov edx, <SVGA Address Port>
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out dx, eax
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mov eax, 1024
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mov edx, <SVGA Value Port>
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out dx, eax
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2. Initialization
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Check the version number
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loop:
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Write into SVGA_REG_ID the maximum SVGA_ID_* the driver supports.
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Read from SVGA_REG_ID.
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Check if it is the value you wrote.
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If yes, VMware SVGA device supports it
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If no, decrement SVGA_ID_* and goto loop
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This algorithm converges.
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Map the frame buffer and the command FIFO
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Read SVGA_REG_FB_START, SVGA_REG_FB_SIZE, SVGA_REG_MEM_START,
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SVGA_REG_MEM_SIZE.
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Map the frame buffer (FB) and the FIFO memory (MEM)
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Get the device capabilities and frame buffer dimensions
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Read SVGA_REG_CAPABILITIES, SVGA_REG_MAX_WIDTH, SVGA_REG_MAX_HEIGHT,
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and SVGA_REG_HOST_BITS_PER_PIXEL / SVGA_REG_BITS_PER_PIXEL.
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Note: The capabilities can and do change without the PCI device ID
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changing or the SVGA_REG_ID changing. A driver should always check
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the capabilities register when loading before expecting any
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capabilities-determined feature to be available. See below for a list
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of capabilities as of this writing.
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Note: If SVGA_CAP_8BIT_EMULATION is not set, then it is possible that
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SVGA_REG_HOST_BITS_PER_PIXEL does not exist and
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SVGA_REG_BITS_PER_PIXEL should be read instead.
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Report the Guest Operating System
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Write SVGA_REG_GUEST_ID with the appropriate value from <guest_os.h>.
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While not required in any way, this is useful information for the
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virtual machine to have available for reporting and sanity checking
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purposes.
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SetMode
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Set SVGA_REG_WIDTH, SVGA_REG_HEIGHT, SVGA_REG_BITS_PER_PIXEL
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Read SVGA_REG_FB_OFFSET
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(SVGA_REG_FB_OFFSET is the offset from SVGA_REG_FB_START of the
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visible portion of the frame buffer)
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Read SVGA_REG_BYTES_PER_LINE, SVGA_REG_DEPTH, SVGA_REG_PSEUDOCOLOR,
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SVGA_REG_RED_MASK, SVGA_REG_GREEN_MASK, SVGA_REG_BLUE_MASK
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Note: SVGA_REG_BITS_PER_PIXEL is readonly if
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SVGA_CAP_8BIT_EMULATION is not set in the capabilities register. Even
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if it is set, values other than 8 and SVGA_REG_HOST_BITS_PER_PIXEL
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will be ignored.
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Enable SVGA
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Set SVGA_REG_ENABLE to 1
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(to disable SVGA, set SVGA_REG_ENABLE to 0. Setting SVGA_REG_ENABLE
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to 0 also enables VGA.)
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Initialize the command FIFO
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The FIFO is exclusively dword (32-bit) aligned. The first four
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dwords define the portion of the MEM area that is used for the
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command FIFO. These are values are all in byte offsets from the
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start of the MEM area.
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A minimum sized FIFO would have these values:
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mem[SVGA_FIFO_MIN] = 16;
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mem[SVGA_FIFO_MAX] = 16 + (10 * 1024);
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mem[SVGA_FIFO_NEXT_CMD] = 16;
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mem[SVGA_FIFO_STOP] = 16;
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Set SVGA_REG_CONFIG_DONE to 1 after these values have been set.
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Note: Setting SVGA_REG_CONFIG_DONE to 0 will stop the device from
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reading the FIFO until it is reinitialized and SVGA_REG_CONFIG_DONE is
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set to 1 again.
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3. SVGA command FIFO protocol
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The FIFO is empty when SVGA_FIFO_NEXT_CMD == SVGA_FIFO_STOP. The
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driver writes commands to the FIFO starting at the offset specified
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by SVGA_FIFO_NEXT_CMD, and then increments SVGA_FIFO_NEXT_CMD.
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The FIFO is full when SVGA_FIFO_NEXT_CMD is one word before SVGA_FIFO_STOP.
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When the FIFO becomes full, the FIFO should be sync'd
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To sync the FIFO
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Write SVGA_REG_SYNC
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Read SVGA_REG_BUSY
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Wait for the value in SVGA_REG_BUSY to be 0
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The FIFO should be sync'd before the driver touches the frame buffer, to
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guarantee that any outstanding BLT's are completed.
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4. Cursor
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When SVGA_CAP_CURSOR is set, hardware cursor support is available. In
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practice, SVGA_CAP_CURSOR will only be set when SVGA_CAP_CURSOR_BYPASS is
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also set and drivers supporting a hardware cursor should only worry about
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SVGA_CAP_CURSOR_BYPASS and only use the FIFO to define the cursor. See
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below for more information.
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5. Pseudocolor
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When the read-only register SVGA_REG_PSEUDOCOLOR is 1, the device is in a
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colormapped mode whose index width and color width are both SVGA_REG_DEPTH.
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Thus far, 8 is the only depth at which pseudocolor is ever used.
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In pseudocolor, the colormap is programmed by writing to the SVGA palette
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registers. These start at SVGA_PALETTE_BASE and are interpreted as
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follows:
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SVGA_PALETTE_BASE + 3*n - The nth red component
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SVGA_PALETTE_BASE + 3*n + 1 - The nth green component
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SVGA_PALETTE_BASE + 3*n + 2 - The nth blue component
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And n ranges from 0 to ((1<<SVGA_REG_DEPTH) - 1).
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Drawing to the Screen
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---------------------
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After initialization, the driver can write directly to the frame buffer. The
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updated frame buffer is not displayed immediately, but only when an update
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command is sent. The update command (SVGA_CMD_UPDATE) defines the rectangle
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in the frame buffer that has been modified by the driver, and causes that
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rectangle to be updated on the screen.
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A complete driver can be developed this way. For increased performance,
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additional commands are available to accelerate common operations. The two
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most useful are SVGA_CMD_RECT_FILL and SVGA_CMD_RECT_COPY.
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After issuing an accelerated command, the FIFO should be sync'd, as described
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above, before writing to the frame buffer.
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Addendum on 7/11/2000
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---------------------
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SVGA_REG_FB_OFFSET and SVGA_REG_BYTES_PER_LINE may change after SVGA_REG_WIDTH
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or SVGA_REG_HEIGHT is set. Also the VGA registers must be written to after
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setting SVGA_REG_ENABLE to 0 to change the display to a VGA mode.
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Addendum on 11/29/2001
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---------------------
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Actually, after changing any of SVGA_REG_WIDTH, SVGA_REG_HEIGHT, and
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SVGA_REG_BITS_PER_PIXEL, all of the registers listed in the 'SetMode'
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initialization section above should be reread. Additionally, when changing
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modes, it can be convenient to set SVGA_REG_ENABLE to 0, change
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SVGA_REG_WIDTH, SVGA_REG_HEIGHT, and SVGA_REG_BITS_PER_PIXEL (if available),
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and then set SVGA_REG_ENABLE to 1 again.
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Capabilities
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------------
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The capabilities register (SVGA_REG_CAPABILITIES) is an array of bits that
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indicates the capabilities of the SVGA emulation. A driver should check
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SVGA_REG_CAPABILITIES every time it loads before relying on any feature that
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is only optionally available.
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Some of the capabilities determine which FIFO commands are available. This
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table shows which capability indicates support for which command.
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FIFO Command Capability
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------------ ----------
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SVGA_CMD_RECT_FILL SVGA_CAP_RECT_FILL
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SVGA_CMD_RECT_COPY SVGA_CAP_RECT_COPY
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SVGA_CMD_DEFINE_BITMAP SVGA_CAP_OFFSCREEN
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SVGA_CMD_DEFINE_BITMAP_SCANLINE SVGA_CAP_OFFSCREEN
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SVGA_CMD_DEFINE_PIXMAP SVGA_CAP_OFFSCREEN
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SVGA_CMD_DEFINE_PIXMAP_SCANLINE SVGA_CAP_OFFSCREEN
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SVGA_CMD_RECT_BITMAP_FILL SVGA_CAP_RECT_PAT_FILL
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SVGA_CMD_RECT_PIXMAP_FILL SVGA_CAP_RECT_PAT_FILL
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SVGA_CMD_RECT_BITMAP_COPY SVGA_CAP_RECT_PAT_FILL
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SVGA_CMD_RECT_PIXMAP_COPY SVGA_CAP_RECT_PAT_FILL
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SVGA_CMD_FREE_OBJECT SVGA_CAP_OFFSCREEN
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SVGA_CMD_RECT_ROP_FILL SVGA_CAP_RECT_FILL +
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SVGA_CAP_RASTER_OP
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SVGA_CMD_RECT_ROP_COPY SVGA_CAP_RECT_COPY +
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SVGA_CAP_RASTER_OP
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SVGA_CMD_RECT_ROP_BITMAP_FILL SVGA_CAP_RECT_PAT_FILL +
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SVGA_CAP_RASTER_OP
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SVGA_CMD_RECT_ROP_PIXMAP_FILL SVGA_CAP_RECT_PAT_FILL +
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SVGA_CAP_RASTER_OP
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SVGA_CMD_RECT_ROP_BITMAP_COPY SVGA_CAP_RECT_PAT_FILL +
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SVGA_CAP_RASTER_OP
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SVGA_CMD_RECT_ROP_PIXMAP_COPY SVGA_CAP_RECT_PAT_FILL +
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SVGA_CAP_RASTER_OP
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SVGA_CMD_DEFINE_CURSOR SVGA_CAP_CURSOR
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SVGA_CMD_DISPLAY_CURSOR SVGA_CAP_CURSOR
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SVGA_CMD_MOVE_CURSOR SVGA_CAP_CURSOR
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SVGA_CMD_DEFINE_ALPHA_CURSOR SVGA_CAP_ALPHA_CURSOR
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SVGA_CMD_DRAW_GLYPH SVGA_CAP_GLYPH
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SVGA_CMD_DRAW_GLYPH_CLIPPED SVGA_CAP_GLYPH_CLIPPING
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SVGA_CMD_ESCAPE SVGA_FIFO_CAP_ESCAPE
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Note: SVGA_CMD_DISPLAY_CURSOR and SVGA_CMD_MOVE_CURSOR should not be used.
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Drivers wishing hardware cursor support should use cursor bypass (see below).
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Other capabilities indicate other functionality as described below:
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SVGA_CAP_CURSOR_BYPASS
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The hardware cursor can be drawn via SVGA Registers (without requiring
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the FIFO be synchronized and will be drawn potentially before any
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outstanding unprocessed FIFO commands).
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Note: Without SVGA_CAP_CURSOR_BYPASS_2, cursors drawn this way still
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appear in the guest's framebuffer and need to be turned off before any
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save under / overlapping drawing and turned back on after. This can
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cause very noticeable cursor flicker.
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SVGA_CAP_CURSOR_BYPASS_2
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Instead of turning the cursor off and back on around any overlapping
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drawing, the driver can write SVGA_CURSOR_ON_REMOVE_FROM_FB and
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SVGA_CURSOR_ON_RESTORE_TO_FB to SVGA_REG_CURSOR_ON. In almost all
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cases these are NOPs and the cursor will be remain visible without
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appearing in the guest framebuffer. In 'direct graphics' modes like
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Linux host fullscreen local displays, however, the cursor will still
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be drawn in the framebuffer, still flicker, and be drawn incorrectly
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if a driver does not use SVGA_CURSOR_ON_REMOVE_FROM_FB / RESTORE_TO_FB.
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SVGA_CAP_8BIT_EMULATION
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SVGA_REG_BITS_PER_PIXEL is writable and can be set to either 8 or
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SVGA_REG_HOST_BITS_PER_PIXEL. Otherwise the only SVGA modes available
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inside a virtual machine must match the host's bits per pixel.
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Note: Some versions which lack SVGA_CAP_8BIT_EMULATION also lack the
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SVGA_REG_HOST_BITS_PER_PIXEL and a driver should assume
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SVGA_REG_BITS_PER_PIXEL is both read-only and initialized to the only
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available value if SVGA_CAP_8BIT_EMULATION is not set.
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SVGA_CAP_OFFSCREEN_1
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SVGA_CMD_RECT_FILL, SVGA_CMD_RECT_COPY, SVGA_CMD_RECT_ROP_FILL,
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SVGA_CMD_RECT_ROP_COPY can operate with a source or destination (or
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both) in offscreen memory.
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Usable offscreen memory is a rectangle located below the last scanline
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of the visible memory:
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x1 = 0
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y1 = (SVGA_REG_FB_SIZE + SVGA_REG_BYTES_PER_LINE - 1) /
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SVGA_REG_BYTES_PER_LINE
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x2 = SVGA_REG_BYTES_PER_LINE / SVGA_REG_DEPTH
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y2 = SVGA_REG_VRAM_SIZE / SVGA_REG_BYTES_PER_LINE
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Cursor Handling
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---------------
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Starting with GSX Server Beta 3 (after 11/15/2000), hardware cursor support
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was added. Actually, both a hardware cursor via the FIFO (SVGA_CAP_CURSOR)
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and a hardware cursor via the SVGA registers (SVGA_CAP_CURSOR_BYPASS) were
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added. SVGA_CAP_CURSOR was never available without SVGA_CAP_CURSOR_BYPASS and
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the FIFO hardware cursor should never be used and may be removed without
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warning in the future.
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Cursor bypass is programmed using the two FIFO commands SVGA_CMD_DEFINE_CURSOR
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and SVGA_CMD_DEFINE_ALPHA_CURSOR in conjunction with the SVGA registers
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SVGA_REG_CURSOR_ID, SVGA_REG_CURSOR_X, SVGA_REG_CURSOR_Y, and
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SVGA_REG_CURSOR_ON.
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A driver defines an AND/XOR hardware cursor using SVGA_CMD_DEFINE_CURSOR to
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assign an ID and establish the AND and XOR masks with the hardware. A driver
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uses SVGA_CMD_DEFINE_ALPHA_CURSOR to define a 32 bit mask whose top 8 bits are
|
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used to blend the cursor image with the pixels it covers. Alpha cursor
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support is only available when SVGA_CAP_ALPHA_CURSOR is set.
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Once a cursor is defined, a driver can draw it to the screen at any time by
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writing the SVGA_REG_CURSOR_ID register with the ID used when the cursor was
|
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defined, writing SVGA_REG_CURSOR_X and SVGA_REG_CURSOR_Y with the location of
|
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the cursor, and SVGA_CURSOR_ON_SHOW to SVGA_REG_CURSOR_ON. The drawing occurs
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when SVGA_REG_CURSOR_ON is written.
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Writing SVGA_CURSOR_ON_HIDE to SVGA_REG_CURSOR_ON will turn the cursor off and
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make it vanish from the display and, if present, from the framebuffer.
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SVGA_CURSOR_ON_REMOVE_FROM_FB will ensure the cursor is not in the
|
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framebuffer, but will only turn it off if there's no other way to remove it.
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SVGA_CURSOR_ON_RESTORE_TO_FB is the complement to
|
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SVGA_CURSOR_ON_REMOVE_FROM_FB. Whenever possible, the device will not put the
|
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cursor in the framebuffer and Remove From / Restore To will be NOPs.
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Note: The cursor must be out of the frame buffer before the driver (or any
|
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agent in the virtual machine) touches an overlapping portion of the frame
|
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buffer, because it is actually drawn into the frame buffer memory in the
|
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case of direct graphics mode (e.g. full screen mode on Linux). The cursor
|
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does not have to be touched before issuing an accelerated command via the
|
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command FIFO, this case is handled by the SVGA device.
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Note: If SVGA_CAP_CURSOR_BYPASS2 is not present, the driver must use
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SVGA_CURSOR_ON_HIDE and SVGA_CURSOR_ON_HIDE to be certain the cursor is out of
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the framebuffer.
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Driver Version Numbers
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----------------------
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The SVGA drivers use the following convention for their version numbers:
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Version 10.0 - The first version that uses the FIFO
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||||
Version 10.1 - The version that uses the hardware cursor emulation via the FIFO
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Version 10.2 - The version that uses the cursor that bypasses the FIFO
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Version 10.3 - The version that can also support the 0405 chipset
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Version 10.4 - The version that knows about SVGA_CAP_CURSOR_BYPASS2
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Version 10.5 - [Never released or well defined]
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Version 10.6 - The version that knows about SVGA_CAP_8BIT_EMULATION
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Version 10.7 - The version that knows about SVGA_CAP_ALPHA_CURSOR
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Version 10.8 - The version that knows about SVGA_CAP_GLYPH
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Version 10.9 - The version that knows about SVGA_CAP_OFFSCREEN_1
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||||
Note that this is merely the convention used by SVGA drivers written and
|
||||
maintained by VMware, Inc. and describes the capabilities of the driver, not
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||||
the virtual hardware. An SVGA driver can only use the intersection of the
|
||||
functionality it supports and the functionality available in the virtual SVGA
|
||||
hardware.
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||||
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||||
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||||
Frequently Asked Questions
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||||
--------------------------
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||||
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1. My driver doesn't display anything, what's going on?
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||||
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||||
First check if you are issuing an SVGA_CMD_UPDATE after drawing to
|
||||
the screen. Another check you can do is to run your driver in full
|
||||
screen mode on a Linux host. In this case you are drawing directly
|
||||
on the frame buffer, so what you draw to the screen will be immediately
|
||||
visible. If nothing is visible in this case, then most likely your
|
||||
driver hasn't mapped the frame buffer correctly.
|
||||
|
||||
A discrepancy between what you get in full screen mode and what you
|
||||
get in window mode indicates that you have a missing or incorrect
|
||||
update command.
|
||||
|
||||
|
||||
2. What's the difference between bitmaps and pixmaps?
|
||||
|
||||
Pixmaps have the same depth as the screen, while bitmaps have depth one.
|
||||
When a bitmap is drawn, the command also takes two colors, foreground and
|
||||
background. The set bits in the bitmap are replaced with the foreground
|
||||
color, and the unset bits are replaced with the background color.
|
||||
|
||||
Pixmaps, on the other hand, can be directly copied to the screen.
|
||||
|
||||
|
||||
3. What's the significance of the ROP in the commands SVGA_CMD_RECT_ROP_FILL,
|
||||
SVGA_CMD_RECT_ROP_BITMAP_COPY, etc. ?
|
||||
|
||||
The ROP in the ...ROP... commands is a raster operation. It has the same
|
||||
significance (and encoding) as it does in X. The ROP value SVGA_ROP_COPY
|
||||
means the source is copied to the destination, which makes these commands the
|
||||
same as their non-ROP counterparts. The most commonly used raster operation
|
||||
other than copy is probably SVGA_ROP_XOR, which combines the source and
|
||||
destination using exclusive-or.
|
||||
|
||||
|
||||
4. Tell me more about bitmaps and pixmaps. For example, the macro
|
||||
SVGA_CMD_DEFINE_BITMAP has a field <scanlines>. What should this be
|
||||
set to? Likewise with SVGA_CMD_DEFINE_PIXMAP. And when should the
|
||||
SCANLINE macros be used?
|
||||
|
||||
OK, I'll use pixmaps as an example. First you have to define the pixmap:
|
||||
|
||||
#define SVGA_CMD_DEFINE_PIXMAP 6
|
||||
/* FIFO layout:
|
||||
Pixmap ID, Width, Height, Depth, <scanlines> */
|
||||
|
||||
The ID is something you choose, which you subsequently use to refer to
|
||||
this pixmap. It must be an integer between 0 and SVGA_MAX_ID.
|
||||
|
||||
The width and height and depth are the dimensions of the pixmap. For now,
|
||||
the depth of the pixmap has to match the depth of the screen.
|
||||
|
||||
The scanlines are the pixels that make up the pixmap, arranged one row
|
||||
at a time. Each row is required to be 32-bit aligned. The macros
|
||||
SVGA_PIXMAP_SCANLINE_SIZE and SVGA_PIXMAP_SIZE give the size of a
|
||||
single scanline, and the size of the entire pixmap, respectively, in
|
||||
32-bit words.
|
||||
|
||||
The second step is to use it:
|
||||
|
||||
#define SVGA_CMD_RECT_PIXMAP_FILL 9
|
||||
/* FIFO layout:
|
||||
Pixmap ID, X, Y, Width, Height */
|
||||
|
||||
The ID here is the one you chose when defining the pixmap. X, Y,
|
||||
Width, and Height define a rectangle on the screen that is to be filled
|
||||
with the pixmap. The pixmap is screen aligned, which means that the
|
||||
coordinates in the pixmap are defined by the screen coordinates modulo
|
||||
the pixmap dimensions.
|
||||
|
||||
If you want a different alignment between the screen and the pixmap,
|
||||
then you can use this command, which allows the pixmap coordinates to
|
||||
be defined:
|
||||
|
||||
#define SVGA_CMD_RECT_PIXMAP_COPY 11
|
||||
/* FIFO layout:
|
||||
Pixmap ID, Source X, Source Y, Dest X, Dest Y, Width,
|
||||
Height */
|
||||
|
||||
The Source X and Source Y are pixmap coordinates, and the Dest X and
|
||||
Dest Y are screen coordinates.
|
||||
|
||||
|
||||
5. OK, now it works briefly, then stops displaying anything. Also,
|
||||
my log file is filled with lines like:
|
||||
Unknown Command 0xff in SVGA command FIFO
|
||||
What's happening?
|
||||
|
||||
The most common problem at this point is that the FIFO gets out
|
||||
of sync. This can happen if the amount of data in the FIFO doesn't
|
||||
match what the VMware SVGA device expects. To track this down, try
|
||||
to isolate the particular command which causes the problem.
|
||||
|
||||
Another way this can happen is if the wraparound in the FIFO isn't
|
||||
done correctly. Here is some example code for writing to the FIFO
|
||||
(mem is an array of 32-bit integers that points to the FIFO memory
|
||||
region):
|
||||
|
||||
while (TRUE) {
|
||||
fifo_min = mem[SVGA_FIFO_MIN] / 4;
|
||||
fifo_max = mem[SVGA_FIFO_MAX] / 4;
|
||||
fifo_next = mem[SVGA_FIFO_NEXT_CMD] / 4;
|
||||
fifo_stop = mem[SVGA_FIFO_STOP] / 4;
|
||||
|
||||
tmp_next = fifo_next+1;
|
||||
if (tmp_next == fifo_max)
|
||||
tmp_next = fifo_min; // Wraparound
|
||||
|
||||
if (tmp_next == fifo_stop) {
|
||||
sync_fifo(); // FIFO full
|
||||
continue; // retry
|
||||
}
|
||||
|
||||
mem[fifo_next] = item;
|
||||
mem[SVGA_FIFO_NEXT_CMD] = tmp_next * 4;
|
||||
break;
|
||||
}
|
||||
|
||||
This isn't the most efficient code, but it should work. It's important
|
||||
to do the increment with wraparound before the FIFO full check, and to
|
||||
check FIFO full before updating the next command pointer.
|
||||
|
||||
|
||||
6. My driver tries to switch modes and either nothing happens or the
|
||||
display becomes completely garbled. What's going on?
|
||||
|
||||
When you change modes, make very sure you reread all of the registers listed
|
||||
above under SetMode. Getting the pitch (SVGA_REG_BYTES_PER_LINE) incorrect
|
||||
will cause a heavily garbled display. Also, if you change
|
||||
SVGA_REG_BITS_PER_PIXEL, make certain that SVGA_CAP_8BIT_EMULATION is present
|
||||
in the SVGA_REG_CAPABILITIES register. Also, even with 8 bit emulation, the
|
||||
driver must still use either 8 bpp or SVGA_REG_HOST_BITS_PER_PIXEL bpp,
|
||||
nothing else.
|
||||
|
||||
|
||||
7. Why does my driver's hardware cursor work when my virtual machine is in
|
||||
window mode, but draw/erase incorrectly or in garbled locations in fullscreen
|
||||
mode?
|
||||
|
||||
You need to make sure you use SVGA_CURSOR_ON_REMOVE_FROM_FB and
|
||||
SVGA_CURSOR_ON_RESTORE_TO_FB _every_ time your driver or the virtual machine
|
||||
touches a region of the framebuffer that overlaps the cursor. If you forget
|
||||
to remove it then it can show up when doing save-under operations or get mixed
|
||||
in with other drawing. If you forget to restore it then can disappear. You
|
||||
also need to make sure SVGA_CAP_CURSOR_BYPASS2 is available, or else you will
|
||||
have to use SVGA_CURSOR_ON_SHOW and SVGA_CURSOR_ON_HIDE (which will flicker,
|
||||
even in window mode), or else a software cursor. Newer version of the virtual
|
||||
SVGA hardware will never put the hardware cursor in the framebuffer while in
|
||||
window mode, so everything will appear to work correctly there.
|
||||
|
||||
|
||||
8. Why do my accelerated glyphs look funny? OR Why does the fifo complain
|
||||
about invalid commands when I draw accelerated glyphs?
|
||||
|
||||
The bitmap data passed to SVGA_CMD_DRAW_GLYPH_* must not have any per-scanline
|
||||
alignment. If there are any remaining bits left in the last byte of a scanline,
|
||||
the first bits of the next scanline should use them.
|
||||
|
||||
The bitmap data as a whole must be 4 byte aligned.
|
||||
|
||||
$XFree86: xc/programs/Xserver/hw/xfree86/drivers/vmware/README,v 1.5 2002/10/16 22:12:53 alanh Exp $
|
||||
--
|
||||
|
||||
Reference in New Issue
Block a user