Re: kern/49398 (i386-current GENERIC (i915drmkms) boot hangs if monitor powered off)

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

The following reply was made to PR kern/49398; it has been noted by GNATS.

From: "John D. Baker" <jdbaker%mylinuxisp.com@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/49398 (i386-current GENERIC (i915drmkms) boot hangs if
 monitor powered off)
Date: Tue, 20 Oct 2015 23:04:31 -0500 (CDT)

 On Tue, 20 Oct 2015, John D. Baker wrote:
 
 > Alas, I wasn't paying attention so I don't know if it's the first or
 > the second spin loop that is stuck.  Adding another line and going again.
 
 It's the second spin loop:
 
 > In "intel_crt.c", in "intel_crt_load_detect()", the last debugging
 > printf displayed is in the construct:
 > 
 > [...]
 >         if (!IS_GEN2(dev)) {
 > 		/* ... not taken ... */
 >         } else {
 > [...]
 >                         
 >                 /*      
 >                  * Wait for the border to be displayed
 >                  */
 >                 while (I915_READ(pipe_dsl_reg) >= vactive)
 >                         ;
 > printf("In %s: line %d\n", __FILE__, __LINE__);
 >                 while ((dsl = I915_READ(pipe_dsl_reg)) <= vsample)
 >                         ;
 > [...]
 >         }
 
 It would appear then, that I915_READ() is working, but that the value
 read remains less than or equal to "vsample" indefinitely.  Adding another
 line to print.
 
 -- 
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