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-rw-r--r--recipes/linux/linux-omap-2.6.27/mru-improve-pixclock-config.diff93
1 files changed, 93 insertions, 0 deletions
diff --git a/recipes/linux/linux-omap-2.6.27/mru-improve-pixclock-config.diff b/recipes/linux/linux-omap-2.6.27/mru-improve-pixclock-config.diff
new file mode 100644
index 0000000000..5a702128f2
--- /dev/null
+++ b/recipes/linux/linux-omap-2.6.27/mru-improve-pixclock-config.diff
@@ -0,0 +1,93 @@
+From: Mans Rullgard <mans@mansr.com>
+Date: Fri, 29 Aug 2008 01:34:39 +0000 (+0100)
+Subject: OMAP: Improve pixel clock configuration
+X-Git-Url: http://git.mansr.com/?p=linux-omap;a=commitdiff_plain;h=01c2d720e59c291de9eb21eb65225f2f215fef84
+
+OMAP: Improve pixel clock configuration
+
+This sets the DSS1_ALWON_FCLK clock as close as possible to a
+multiple of the requested pixel clock, while keeping it below
+the 173MHz limit.
+
+Due to of the structure of the clock tree, dss1_alwon_fck cannot
+be set directly, and we must use dpll4_m4_ck instead.
+
+Signed-off-by: Mans Rullgard <mans@mansr.com>
+---
+
+diff --git a/drivers/video/omap/dispc.c b/drivers/video/omap/dispc.c
+index 64bf333..888d2c2 100644
+--- a/drivers/video/omap/dispc.c
++++ b/drivers/video/omap/dispc.c
+@@ -177,6 +177,7 @@ static struct {
+
+ struct clk *dss_ick, *dss1_fck;
+ struct clk *dss_54m_fck;
++ struct clk *dpll4_m4_ck;
+
+ enum omapfb_update_mode update_mode;
+ struct omapfb_device *fbdev;
+@@ -736,19 +737,34 @@ static void setup_color_conv_coef(void)
+ MOD_REG_FLD(at2_reg, (1 << 11), ct->full_range);
+ }
+
++#define MAX_FCK 173000000
++
+ static void calc_ck_div(int is_tft, int pck, int *lck_div, int *pck_div)
+ {
++ unsigned long prate = clk_get_rate(clk_get_parent(dispc.dpll4_m4_ck));
++ unsigned long pcd_min = is_tft? 2: 3;
++ unsigned long fck_div;
+ unsigned long fck, lck;
+
+- *lck_div = 1;
+ pck = max(1, pck);
++
++ if (pck * pcd_min > MAX_FCK) {
++ dev_warn(dispc.fbdev->dev, "pixclock %d kHz too high.\n",
++ pck / 1000);
++ pck = MAX_FCK / pcd_min;
++ }
++
++ fck = pck * 2;
++ fck_div = (prate + pck) / fck;
++ if (fck_div > 16)
++ fck_div /= (fck_div + 15) / 16;
++ if (fck_div < 1)
++ fck_div = 1;
++ clk_set_rate(dispc.dpll4_m4_ck, prate / fck_div);
+ fck = clk_get_rate(dispc.dss1_fck);
+- lck = fck;
+- *pck_div = (lck + pck - 1) / pck;
+- if (is_tft)
+- *pck_div = max(2, *pck_div);
+- else
+- *pck_div = max(3, *pck_div);
++
++ *lck_div = 1;
++ *pck_div = (fck + pck - 1) / pck;
+ if (*pck_div > 255) {
+ *pck_div = 255;
+ lck = pck * *pck_div;
+@@ -909,11 +925,21 @@ static int get_dss_clocks(void)
+ return PTR_ERR(dispc.dss_54m_fck);
+ }
+
++ if (IS_ERR((dispc.dpll4_m4_ck =
++ clk_get(dispc.fbdev->dev, "dpll4_m4_ck")))) {
++ dev_err(dispc.fbdev->dev, "can't get dpll4_m4_ck");
++ clk_put(dispc.dss_ick);
++ clk_put(dispc.dss1_fck);
++ clk_put(dispc.dss_54m_fck);
++ return PTR_ERR(dispc.dss_54m_fck);
++ }
++
+ return 0;
+ }
+
+ static void put_dss_clocks(void)
+ {
++ clk_put(dispc.dpll4_m4_ck);
+ clk_put(dispc.dss_54m_fck);
+ clk_put(dispc.dss1_fck);
+ clk_put(dispc.dss_ick);