linux/drivers/video/via/iface.c

79 lines
2.2 KiB
C

/*
* Copyright 1998-2008 VIA Technologies, Inc. All Rights Reserved.
* Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation;
* either version 2, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even
* the implied warranty of MERCHANTABILITY or FITNESS FOR
* A PARTICULAR PURPOSE.See the GNU General Public License
* for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "global.h"
/* Get frame buffer size from VGA BIOS */
unsigned int viafb_get_memsize(void)
{
unsigned int m;
/* If memory size provided by user */
if (viafb_memsize)
m = viafb_memsize * Mb;
else {
m = (unsigned int)viafb_read_reg(VIASR, SR39);
m = m * (4 * Mb);
if ((m < (16 * Mb)) || (m > (64 * Mb)))
m = 16 * Mb;
}
DEBUG_MSG(KERN_INFO "framebuffer size = %d Mb\n", m / Mb);
return m;
}
/* Get Video Buffer Starting Physical Address(back door)*/
unsigned long viafb_get_videobuf_addr(void)
{
struct pci_dev *pdev = NULL;
unsigned char sys_mem;
unsigned char video_mem;
unsigned long sys_mem_size;
unsigned long video_mem_size;
/*system memory = 256 MB, video memory 64 MB */
unsigned long vmem_starting_adr = 0x0C000000;
pdev =
(struct pci_dev *)pci_get_device(VIA_K800_BRIDGE_VID,
VIA_K800_BRIDGE_DID, NULL);
if (pdev != NULL) {
pci_read_config_byte(pdev, VIA_K800_SYSTEM_MEMORY_REG,
&sys_mem);
pci_read_config_byte(pdev, VIA_K800_VIDEO_MEMORY_REG,
&video_mem);
video_mem = (video_mem & 0x70) >> 4;
sys_mem_size = ((unsigned long)sys_mem) << 24;
if (video_mem != 0)
video_mem_size = (1 << (video_mem)) * 1024 * 1024;
else
video_mem_size = 0;
vmem_starting_adr = sys_mem_size - video_mem_size;
pci_dev_put(pdev);
}
DEBUG_MSG(KERN_INFO "Video Memory Starting Address = %lx \n",
vmem_starting_adr);
return vmem_starting_adr;
}