[Xorg-driver-geode] [PATCH] Document LXGetLegacyPanelMode(..)

[Christian Gmeiner]

Oh and I forgot to say that the AMD source is under LGPL.

/*
* Copyright (c) 2006-2008 Advanced Micro Devices,Inc. ("AMD").
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of the
* License, or (at your option) any later version.
*
* This code is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.

* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307 USA
*/


---
Christian Gmeiner, MSc


2012/9/27  <christian.gmeiner at gmail.com>:
> From: root <root at OT.(none)>
>
> It is quite hard to understand all this magic numbers and bits so
> add some defined and comments to make it understandable.
> All the needed defines are taken from gplvsa_ii source code, which
> can be found at coreboot project.
>
> Signed-off-by: Christian Gmeiner <christian.gmeiner at gmail.com>
> ---
>  src/lx_panel.c |   42 +++++++++++++++++++++++++++++++++++-------
>  1 files changed, 35 insertions(+), 7 deletions(-)
>
> diff --git a/src/lx_panel.c b/src/lx_panel.c
> index 6b5d4ed..576ad21 100644
> --- a/src/lx_panel.c
> +++ b/src/lx_panel.c
> @@ -39,8 +39,24 @@
>  #include "xf86Modes.h"
>  #include "geode.h"
>
> +
> +#define VRC_INDEX                       0xAC1C  // Index register
> +#define VRC_DATA                        0xAC1E  // Data register
> +#define VR_UNLOCK                       0xFC53  // Virtual register unlock code
> +
> +#define VRC_VG                          0x02
> +
> +#define VG_CONFIG                       0x00    // Main configuration register
> +#define VG_CFG_DSMASK                   0x0700  // Active display mask bits
> +#define VG_CFG_DSCRT                    0x0000  // Active display is CRT
> +#define VG_CFG_DSPAN                    0x0100  // Active display is panel
> +#define VG_CFG_DSTV                     0x0200  // Active display is TV
> +#define VG_CFG_DSSIM                    0x0400  // Simultaneous CRT
> +
> +#define VG_FP_TYPE                      0x02    // Flat panel type data
> +
>  #define LX_READ_VG(reg) \
> -                (outw(0xAC1C,0xFC53), outw(0xAC1C,0x0200|(reg)), inw(0xAC1E))
> +                (outw(VRC_INDEX, VR_UNLOCK), outw(VRC_INDEX, (VRC_VG << 8) | (reg)), inw(VRC_DATA))
>
>  /* This is borrowed from xerver/hw/xfree86/modes */
>
> @@ -79,12 +95,24 @@ DisplayModeRec lx_panel_modes[] = {
>  DisplayModePtr
>  LXGetLegacyPanelMode(ScrnInfoPtr pScrni)
>  {
> -    unsigned short reg = LX_READ_VG(0x00);
> -    unsigned char ret = (reg >> 8) & 0x07;
> -
> -    if ((ret == 1 || ret == 5)) {
> -
> -        reg = LX_READ_VG(0x02);
> +    /* read Active display configuration */
> +    unsigned short reg = LX_READ_VG(VG_CONFIG);
> +    unsigned char ret = (reg & VG_CFG_DSMASK);
> +
> +    if ((ret == VG_CFG_DSPAN || ret == (VG_CFG_DSPAN | VG_CFG_DSSIM))) {
> +
> +        /* read panel resolution
> +         *
> +         * 0x00: 640x480
> +         * 0x01: 800x600
> +         * 0x02: 1004x768
> +         * 0x03: 1152x864
> +         * 0x04: 1280x768
> +         * 0x05: reserved
> +         * 0x06: reserved
> +         * 0x07: reserved
> +         */
> +        reg = LX_READ_VG(VG_FP_TYPE);
>          ret = (reg >> 3) & 0x07;
>
>          /* FIXME: 7 is reserved in default. We use this value to support
> --
> 1.7.2.5
>