From 1ce029968718477149e7f1fb245a8e82c690cc4a Mon Sep 17 00:00:00 2001 From: "Mark A. Greer" Date: Mon, 30 Apr 2012 16:57:09 -0700 Subject: 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 [khilman@ti.com: use soc_is_am35xx() instead of cpu_is_am35xx()] Signed-off-by: Kevin Hilman --- arch/arm/mach-omap2/id.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c index f611e3097157..38ae74f8e77a 100644 --- a/arch/arm/mach-omap2/id.c +++ b/arch/arm/mach-omap2/id.c @@ -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. -- cgit v1.2.1