sunxi: video: Modify sunxi_lcdc_pll_set to work with both tcon0 and tcon1
Modify sunxi_lcdc_pll_set to work with both tcon0 and tcon1, this is a
preparation patch for adding lcd support.
While at it also swap the divider search order, searching from low to
high, as the comment above the code says we should do. In cases where there
are multiple solutions this will result in picking a lower pll clock and
divider, which is more stable and saves power.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
diff --git a/drivers/video/sunxi_display.c b/drivers/video/sunxi_display.c
index f990ab9..e4f95d4 100644
--- a/drivers/video/sunxi_display.c
+++ b/drivers/video/sunxi_display.c
@@ -323,20 +323,29 @@
/*
* LCDC, what allwinner calls a CRTC, so timing controller and serializer.
*/
-static void sunxi_lcdc_pll_set(int dotclock, int *clk_div, int *clk_double)
+static void sunxi_lcdc_pll_set(int tcon, int dotclock,
+ int *clk_div, int *clk_double)
{
struct sunxi_ccm_reg * const ccm =
(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
- int value, n, m, diff;
+ int value, n, m, min_m, max_m, diff;
int best_n = 0, best_m = 0, best_diff = 0x0FFFFFFF;
int best_double = 0;
+ if (tcon == 0) {
+ min_m = 6;
+ max_m = 127;
+ } else {
+ min_m = 1;
+ max_m = 15;
+ }
+
/*
* Find the lowest divider resulting in a matching clock, if there
* is no match, pick the closest lower clock, as monitors tend to
* not sync to higher frequencies.
*/
- for (m = 15; m > 0; m--) {
+ for (m = min_m; m <= max_m; m++) {
n = (m * dotclock) / 3000;
if ((n >= 9) && (n <= 127)) {
@@ -373,9 +382,17 @@
clock_set_pll3(best_n * 3000000);
- writel(CCM_LCD_CH1_CTRL_GATE |
- (best_double ? CCM_LCD_CH1_CTRL_PLL3_2X : CCM_LCD_CH1_CTRL_PLL3) |
- CCM_LCD_CH1_CTRL_M(best_m), &ccm->lcd0_ch1_clk_cfg);
+ if (tcon == 0) {
+ writel(CCM_LCD_CH0_CTRL_GATE | CCM_LCD_CH0_CTRL_RST |
+ (best_double ? CCM_LCD_CH0_CTRL_PLL3_2X :
+ CCM_LCD_CH0_CTRL_PLL3),
+ &ccm->lcd0_ch0_clk_cfg);
+ } else {
+ writel(CCM_LCD_CH1_CTRL_GATE |
+ (best_double ? CCM_LCD_CH1_CTRL_PLL3_2X :
+ CCM_LCD_CH1_CTRL_PLL3) |
+ CCM_LCD_CH1_CTRL_M(best_m), &ccm->lcd0_ch1_clk_cfg);
+ }
*clk_div = best_m;
*clk_double = best_double;
@@ -453,7 +470,7 @@
writel(SUNXI_LCDC_X(mode->hsync_len) | SUNXI_LCDC_Y(mode->vsync_len),
&lcdc->tcon1_timing_sync);
- sunxi_lcdc_pll_set(mode->pixclock_khz, clk_div, clk_double);
+ sunxi_lcdc_pll_set(1, mode->pixclock_khz, clk_div, clk_double);
}
#ifdef CONFIG_MACH_SUN6I