[okl4-developer] Starting with graphic output

[Geoffrey Lee]

On Mon, May 05, 2008 at 03:43:51PM +0000, Remy Gottschalk wrote:
> Hi Geoffrey
> 
> On Thu, 2008-05-01 at 18:11 +1000, Geoffrey Lee wrote:
> > On Tue, Apr 29, 2008 at 04:05:54PM +0000, Remy Gottschalk wrote:
> > > Hi Nelson,
> > > 
> > > To come back to the initial problem, any news concerning the invalid
> > > memory dereference at 0x18 ?
> > 
> > Hi Remy
> > 
> > This occurs during a deference of the ms pointer in eas_map() in 
> > iguana/server/src/eas.c
> > 
> >     ms = objtable_lookup((void *)base);
> >  
> >     /*
> >      * XXX: we need to check the attribs and rights
> >      */
> >     attrib &= ms->attributes;
> > 
> > it should return failure (-1) if the object does not exist.  Fixing this
> > alone does not help you entirely because when you mmap() it calls eas_map(), 
> > the physical memory location has to be first made known to Iguana.
> > These regions must be made known in the machines.py file with
> > appropriate setup support by the build system.  If you just want to fix
> > this quickly you can add the appropriate range check for your
> > framebuffer there.
> > 
> 
> So if I understand well I got two solutions :
> 
> The quick'n dirty is to force the mapping by hard checking values in
> eas_map().
> And the proper one is to add the right memory region in the
> configuration files.
> 
> For the quick one I must admit that I am a little lost and need a little
> more help about how to do.

I do something like this, but of course we'd rather you do it properly: 

+    if (!ms) {
+        if ((base >= 0xf0000000)) /* fb phys */
+            badfb = 1;
+        else {
+            printf("%s: base 0x%lx end 0x%lx\n", __func__, base, end);
+            return -1;
+        }
+    }
 
     /*
      * XXX: we need to check the attribs and rights 
      */
-    attrib &= ms->attributes;
+    if (ms)
+        attrib &= ms->attributes;
     rwx = L4_Rights(src_fpage);
 
     /*
      * XXX: we map 4k fpages even when bigger mappings are possible 
      */
     for (virt = base; virt < end; virt += BASE_PAGESIZE) {
-        if (!memsection_lookup_phys(ms, virt, &phys, &size,
         &iguana_pd))
-            continue;
+        if (!badfb) {
+            if (!memsection_lookup_phys(ms, virt, &phys, &size,
&iguana_pd))
+                continue;
+        } else {
+            phys = base;
+            size = L4_Size(src_fpage);
+        }




> 
> Concerning the proper, is it something similar to what is done for the
> vga memory ? ie adding something like :
> memory['fb'] = [Region(0xF0000000L, 0xF0400000L, "dedicated")]
> to the class ia32_pc99_fb in platform/pc99/tools/machines.py
> and/or a linux_fb flag with the right stuff
> in ./projects/iguana/SConstruct to add a memsection to Linux.


Yes, that's right.  This would be the preferred solution.

> 
> Regards,

	-gl

> 
> -- 
> Remy Gottschalk - rgottschalk at linagora.com
> Ingénieur informatique embarquée
> Groupe LINAGORA - http://www.linagora.com
> Tél.: +33(0)1 58 18 68 28 - Fax : +33(0)1 58 18 68 29
> 
> 

--