OMAP4 has 2 LCD channels and corresponding DISPC_DIVISOR1 and DISPC_DIVISOR2 registers to configure the pixel clock frequency, for the respective LCD displays. There is also DISPC_DIVISOR register, which by default has the ENABLE bit set to zero, for backward compatibility mode. Hence the logical clock divider of DISPC_DIVISOR1.LCD, gets used for core func clk configuration. The default value of DISPC_DIVISOR1.LCD is 4. If only the secondary LCD is enabled, at high pixel resolutions the core clk lags behind the pixel clock, causing stair-step effect (diagonal lines with tearing) on the display. Hence DISPC_DIVISOR.ENABLE is set to 1, and the core functional clock is set independently and exclusively in DISPC_DIVISOR.LCD. - Added the above as dss_features ----------------------------------------------------- Base ---- url = git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git branch "master" commit 1bae4ce27c9c90344f23c65ea6966c50ffeae2f5 tag 2.6.38-rc2 Applies over: ------------- 1. Patch mentioned in http://www.mail-archive.com/linux-omap@xxxxxxxxxxxxxxx/msg42384.html [PATCH] OMAP: counter_32k: init clocksource as part of machine timer init (This patch is required for OMAP bootup) 2. v10 of OMAP2,3 DSS2 HWMOD https://patchwork.kernel.org/patch/500191/ 3. v3 of DSS2: Generalize clock names https://patchwork.kernel.org/patch/520191/ 4. v3 of DSS2: OMAP4 DSS HWMOD : https://patchwork.kernel.org/patch/511211/ 5. OMAP: DSS2: Common IRQ handler for all OMAPs https://patchwork.kernel.org/patch/526241/ 6. OMAP4: DSS2: Adding fclk support for DPI interface https://patchwork.kernel.org/patch/529381/ --------------------------------------------------------- Raghuveer Murthy (4): OMAP: DSS2: Adding dss_features for independent core clk divider OMAP: DSS2: Renaming register macro DISPC_DIVISOR(ch) OMAP: DSS2: Adding macro for DISPC_DIVISOR register OMAP4: DSS2: Using dss_features to set independent core clock divider drivers/video/omap2/dss/dispc.c | 57 ++++++++++++++++++++++++------- drivers/video/omap2/dss/dss_features.c | 2 +- drivers/video/omap2/dss/dss_features.h | 2 + 3 files changed, 47 insertions(+), 14 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
