Commit 1ce02996 authored Apr 30, 2012 by Mark A. Greer Committed by Kevin Hilman May 11, 2012

arm: omap3: am35x: Don't mark missing features as present



The Chip Identification register on the am35x family of SoCs
has bits 12, 7:5, and 3:2 marked as reserved and are read as
zeroes.  Unfortunately, on other omap SoCs, a 0 bit means a
feature is "Full Use" so the OMAP3_CHECK_FEATURE() macro
called by omap3_check_features() will incorrectly interpret
those zeroes to mean that a feature is present even though it
isn't.  To fix that, the feature bits that are incorrectly
set (namely, OMAP3_HAS_IVA and OMAP3_HAS_ISP) need to be
cleared after all of the calls to OMAP3_CHECK_FEATURE() in
omap3_check_features() are made.

Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
[khilman@ti.com: use soc_is_am35xx() instead of cpu_is_am35xx()]
Signed-off-by: Kevin Hilman <khilman@ti.com>

parent 99b59df0

arch/arm/mach-omap2/id.c

+11 −0

Original line number	Diff line number	Diff line
		@@ -246,6 +246,17 @@ void __init omap3xxx_check_features(void)

		omap_features \|= OMAP3_HAS_SDRC;

		/*
		* am35x fixups:
		* - The am35x Chip ID register has bits 12, 7:5, and 3:2 marked as
		* reserved and therefore return 0 when read. Unfortunately,
		* OMAP3_CHECK_FEATURE() will interpret some of those zeroes to
		* mean that a feature is present even though it isn't so clear
		* the incorrectly set feature bits.
		*/
		if (soc_is_am35xx())
		omap_features &= ~(OMAP3_HAS_IVA \| OMAP3_HAS_ISP);

		/*
		* TODO: Get additional info (where applicable)
		* e.g. Size of L2 cache.