Messages in this thread | | | Date | Thu, 28 Jul 2005 16:50:08 -0400 | From | Jon Smirl <> | Subject | Re: [Linux-fbdev-devel] Re: [PATCH] fbdev: colormap fixes |
| |
I've verified now that all ATI R300+ chips have 10bit cmaps. These are pretty common so I'd be in favor of making this into a binary attribute where I can get/set the whole table at once. Given that OpenGL is already supporting 12 and 16 bits these tables are only going to get much larger.
1024 entries * 5 fields * 2 bytes = 10KB -- too big for a text attribute.
65536 entries * 5 fields * 2 bytes = 655KB -- way too big for a text attribute.
The bits_per_pixel sysfs attribute is an easy way to tell how many entries you need. You can just set it at 4, 8, 10, etc until you get an error. Now you know the max. 2^n and you know how many entries.
-- Jon Smirl jonsmirl@gmail.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |