Re: [PATCH] radeonfb: probe BIOS scratch registers for flat panel info

[Michael Clark]

BTW - DDC detection is not supported with my LCD. This is the same problem
I had with Xfree86 4.1.99 untill they added detection with BIOS registers.
The X guys must have come to the same conclusion.

# get-edid
get-edid: get-edid version 1.4.1

     Performing real mode VBE call
     Interrupt 0x10 ax=0x4f00 bx=0x0 cx=0x0
     Function supported
     Call successful

     VBE version 200
     VBE string at 0x11110 "ATI RADEON III"

VBE/DDC service about to be called
     Report DDC capabilities

     Performing real mode VBE call
     Interrupt 0x10 ax=0x4f15 bx=0x0 cx=0x0
     Function supported
     Call successful

     Monitor and video card combination does not support DDC1 transfers
     Monitor and video card combination does not support DDC2 transfers
     0 seconds per 128 byte EDID block transfer
     Screen is not blanked during DDC transfer

Reading next EDID block

VBE/DDC service about to be called
     Read EDID

     Performing real mode VBE call
     Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0
     Function supported
     Call failed

The EDID data should not be trusted as the VBE call failed
Error: output block unchanged

Also solved my vanishing cursor problem by removing this line:

  	radeon_update_default_var(rinfo);
- 	radeonfb_default_var.bits_per_pixel = 32;
  	return 1;

Seems the cursor only works correctly in 8bit mode.

~mc

Michael Clark wrote:

> Hi Ani,
> 
> I tried the latest 2.4.18-pre1 radeonfb driver with the posted compile
> fixes (*) on my Radeon LY(M6) based laptop with Samsumg Flat Panel and
> it still doesn't correctly detect my flat panel.
> 
> So I had a look at the code and noticed EDID DFP detection is only used
> on PPC through open firmware info and DFP info is not probed on other 
> archs.
> 
> I rememeber having the same problem with XFree 4.1.99 radeon code a couple
> months back but a fix was added to get the DFP info from the BIOS scratch
> registers. Here's a patch that adds probing of BIOS scratch registers (if
> available) for DFP info - same logic as in radeon XFree driver.
> 
> The patch applies on top of 2.4.18-pre2 with the radeon compile fix
> referenced here:
> 
>   (*) http://marc.theaimsgroup.com/?l=linux-kernel&m=101046020806692&w=2
> 
> radeonfb now correctly comes up on my laptop in 1400x1050 mode.
> 
> radeonfb: ref_clk=2700, ref_div=60, xclk=16600 from BIOS
> radeonfb: Failed to detect DFP panel size using EDID
> radeonfb: panel ID string: Samsung LTN150P1-L02
> radeonfb: detected DFP panel size from BIOS: 1400x1050
> Console: switching to colour frame buffer device 175x65
> radeonfb: ATI Radeon M6 LY  DDR SGRAM 16 MB
> radeonfb: DVI port DFP monitor connected
> radeonfb: CRT port no monitor connected
> 
> The only remaining problem I have is when switching from X back to the
> console I loose my cursor. Other virtual consoles seem to have cursors of
> varying colors - any ideas?
> 
> ~mc
> 
> 
> ------------------------------------------------------------------------
> 
> --- linux-2.4.18-pre2-radeonfix-orig/drivers/video/radeonfb.c	Mon Jan 14 11:53:49 2002
> +++ linux-2.4.18-pre2-radeonfix/drivers/video/radeonfb.c	Mon Jan 14 14:55:19 2002
> @@ -645,6 +645,7 @@
>  static char *radeon_find_rom(struct radeonfb_info *rinfo);
>  static void radeon_get_pllinfo(struct radeonfb_info *rinfo, char *bios_seg);
>  static void radeon_get_moninfo (struct radeonfb_info *rinfo);
> +static int radeon_get_bios_dfpinfo (struct radeonfb_info *rinfo);
>  static int radeon_get_dfpinfo (struct radeonfb_info *rinfo);
>  static void radeon_get_EDID(struct radeonfb_info *rinfo);
>  static int radeon_dfp_parse_EDID(struct radeonfb_info *rinfo);
> @@ -933,7 +936,8 @@
>  
>  	if ((rinfo->dviDisp_type == MT_DFP) || (rinfo->dviDisp_type == MT_LCD) ||
>  	    (rinfo->crtDisp_type == MT_DFP)) {
> -		if (!radeon_get_dfpinfo(rinfo)) {
> +		if (!radeon_get_dfpinfo(rinfo) &&
> +		    !radeon_get_bios_dfpinfo(rinfo)) {
>  			iounmap ((void*)rinfo->mmio_base);
>  			release_mem_region (rinfo->mmio_base_phys,
>  					    pci_resource_len(pdev, 2));
> @@ -1365,6 +1369,48 @@
>  
>  
>  
> +static int radeon_get_bios_dfpinfo (struct radeonfb_info *rinfo)
> +{
> +	char *biosstart, *fpbiosstart;
> +	char *tmp, *tmp0;
> +	int i;
> +	char stmp[30];
> +
> +	if(!(biosstart = radeon_find_rom(rinfo))) goto out;
> +	if(!(fpbiosstart = biosstart + readw(biosstart + 0x48))) goto out;
> +	if(!(tmp = biosstart + readw(fpbiosstart + 0x40))) goto out;
> +
> +	for(i=0; i<24; i++) stmp[i] = readb(tmp+i+1);
> +	stmp[24] = 0; 
> +	printk("radeonfb: panel ID string: %s\n", stmp);
> +	rinfo->panel_xres = readw(tmp + 25);
> +	rinfo->panel_yres = readw(tmp + 27);
> +	printk("radeonfb: detected DFP panel size from BIOS: %dx%d\n",
> +	       rinfo->panel_xres, rinfo->panel_yres);
> +	for(i=0; i<20; i++) {
> +		tmp0 = biosstart + readw(tmp+64+i*2);
> +		if(tmp0 == 0) break;
> +		if((readw(tmp0) == rinfo->panel_xres) &&
> +		   (readw(tmp0+2) == rinfo->panel_yres)) {
> +			rinfo->hblank = (readw(tmp0+17) - readw(tmp0+19)) * 8;
> +			rinfo->hOver_plus = (readw(tmp0+21) - readw(tmp0+19) - 1) * 8;
> +			rinfo->hSync_width = readb(tmp0+23) * 8;
> +			rinfo->vblank = readw(tmp0+24) - readw(tmp0+26);
> +			rinfo->vOver_plus = (readw(tmp0+28) & 0x7ff) - readw(tmp0+26);
> +			rinfo->vSync_width = (readw(tmp0+28) & 0xf800) >> 11;
> +			rinfo->clock = readw(tmp0+9);
> +			radeon_update_default_var(rinfo);
> +			radeonfb_default_var.bits_per_pixel = 32;
> +			return 1;
> +		}
> +	}
> + out:
> +	printk("radeonfb: Failed to detect DFP panel size using BIOS\n");
> +	return 0;
> +}
> +
> +
> +
>  static int radeon_get_dfpinfo (struct radeonfb_info *rinfo)
>  {
>  	unsigned int tmp;
> @@ -1406,7 +1452,7 @@
>  			rinfo->panel_xres = 1600;
>  			break;
>  		default:
> -			printk("radeonfb: Failed to detect DFP panel size\n");
> +			printk("radeonfb: Failed to detect DFP panel size using EDID\n");
>  			return 0;
>  	}
>  
>