From b5ed0359e7d6a489fc8a293d8b427515e08b90dc Mon Sep 17 00:00:00 2001
From: Darren Etheridge <detheridge@ti.com>
Date: Tue, 9 Apr 2013 16:49:38 -0500
Subject: [PATCH 12/15] Fix for screen rolling when video played back in
browser on BeagleBone Black This value might need some tweaking, but it
effectively allows the LCDC and the ARM to play fairer in memory, so the LCDC
does not get starved causing the screen to roll See Page 439 in spruh73g
(AM33xx TRM) for details
---
arch/arm/cpu/armv7/am33xx/ddr.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/arch/arm/cpu/armv7/am33xx/ddr.c b/arch/arm/cpu/armv7/am33xx/ddr.c
index d1e2fd3..3a93db1 100644
--- a/arch/arm/cpu/armv7/am33xx/ddr.c
+++ b/arch/arm/cpu/armv7/am33xx/ddr.c
@@ -21,6 +21,12 @@ http://www.ti.com/
#include <asm/io.h>
#include <asm/emif.h>
+/* This value might need some tweaking, but it effectively allows the LCDC */
+/* and the ARM to play fairer in memory, so the LCDC does not get starved causing */
+/* the screen to roll */
+/* See Page 439 in spruh73g (AM33xx TRM) for details */
+#define AM33XX_INT_CONFIG_COUNT 0x00303030
+
/**
* Base address for EMIF instances
*/
@@ -79,6 +85,10 @@ void set_sdram_timings(const struct emif_regs *regs, int nr)
writel(regs->sdram_tim2, &emif_reg[nr]->emif_sdram_tim_2_shdw);
writel(regs->sdram_tim3, &emif_reg[nr]->emif_sdram_tim_3);
writel(regs->sdram_tim3, &emif_reg[nr]->emif_sdram_tim_3_shdw);
+
+ /* Configure INT_CONFIG value so that LCDC does not get stalled */
+ /* for a long time if ARM is accessing memory */
+ writel(AM33XX_INT_CONFIG_COUNT, &emif_reg[nr]->emif_l3_config);
}
/**
--
1.8.3.1