From b923d40dd4211c4ef7d4efa2bd81b7ca1d8744c1 Mon Sep 17 00:00:00 2001 From: Archit Taneja Date: Thu, 6 Oct 2011 18:04:08 -0600 Subject: ARM: OMAP2PLUS: DSS: Ensure DSS works correctly if display is enabled in bootloader Resetting DISPC when a DISPC output is enabled causes the DSS to go into an inconsistent state. Thus if the bootloader has enabled a display, the hwmod code cannot reset the DISPC module just like that, but the outputs need to be disabled first. Add function dispc_disable_outputs() which disables all active overlay manager and ensure all frame transfers are completed. Modify omap_dss_reset() to call this function and clear DSS_CONTROL, DSS_SDI_CONTROL and DSS_PLL_CONTROL so that DSS is in a clean state when the DSS2 driver starts. This resolves the hang issue(caused by a L3 error during boot) seen on the beagle board C3, which has a factory bootloader that enables display. The issue is resolved with this patch. Thanks to Tomi and Sricharan for some additional testing. Acked-by: Tomi Valkeinen Tested-by: R, Sricharan Signed-off-by: Archit Taneja [paul@pwsan.com: restructured code, removed omap_{read,write}l(), removed cpu_is_omap*() calls and converted to dev_attr] Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/omap_hwmod_2430_data.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm/mach-omap2/omap_hwmod_2430_data.c') diff --git a/arch/arm/mach-omap2/omap_hwmod_2430_data.c b/arch/arm/mach-omap2/omap_hwmod_2430_data.c index 6f0365388dfc..c4f56cb60d7d 100644 --- a/arch/arm/mach-omap2/omap_hwmod_2430_data.c +++ b/arch/arm/mach-omap2/omap_hwmod_2430_data.c @@ -1004,6 +1004,7 @@ static struct omap_hwmod omap2430_dss_dispc_hwmod = { .slaves = omap2430_dss_dispc_slaves, .slaves_cnt = ARRAY_SIZE(omap2430_dss_dispc_slaves), .flags = HWMOD_NO_IDLEST, + .dev_attr = &omap2_3_dss_dispc_dev_attr }; /* l4_core -> dss_rfbi */ -- cgit v1.2.3