imx6: clock: add support to get LCD pixel clock rate

Add the get_lcd_clk() function to get the LCD pixel clock rate.

The patch has been tested on imx6ul platform.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>

2 files changed, 60 insertions, 0 deletions

diff --git a/arch/arm/include/asm/arch-mx6/clock.h b/arch/arm/include/asm/arch-mx6/clock.h
index 8ae4971..81af89c 100644
--- a/arch/arm/include/asm/arch-mx6/clock.h
+++ b/arch/arm/include/asm/arch-mx6/clock.h
@@ -41,6 +41,8 @@ enum mxc_clock {
 	MXC_SATA_CLK,
 	MXC_NFC_CLK,
 	MXC_I2C_CLK,
+	MXC_LCDIF1_CLK,
+	MXC_LCDIF2_CLK,
 };
 
 enum ldb_di_clock {
diff --git a/arch/arm/mach-imx/mx6/clock.c b/arch/arm/mach-imx/mx6/clock.c
index 17d8dcd..267d86a 100644
--- a/arch/arm/mach-imx/mx6/clock.c
+++ b/arch/arm/mach-imx/mx6/clock.c
@@ -418,6 +418,60 @@ static u32 get_uart_clk(void)
 	return freq / (uart_podf + 1);
 }
 
+static u32 get_lcd_clk(unsigned int ifnum)
+{
+	u32 pll_rate;
+	u32 pred, postd;
+
+	if (!is_mx6sx() && !is_mx6ul() && !is_mx6ull() && !is_mx6sl() &&
+	    !is_mx6sll()) {
+		debug("This chip does't support lcd\n");
+		return 0;
+	}
+
+	pll_rate = decode_pll(PLL_VIDEO, MXC_HCLK);
+	if (ifnum == 1) {
+		if (!is_mx6sl()) {
+			pred = __raw_readl(&imx_ccm->cscdr2);
+			pred &= MXC_CCM_CSCDR2_LCDIF1_PRE_DIV_MASK;
+			pred = pred >> MXC_CCM_CSCDR2_LCDIF1_PRE_DIV_OFFSET;
+
+			postd = readl(&imx_ccm->cbcmr);
+			postd &= MXC_CCM_CBCMR_LCDIF1_PODF_MASK;
+			postd = postd >> MXC_CCM_CBCMR_LCDIF1_PODF_OFFSET;
+		} else {
+			pred = __raw_readl(&imx_ccm->cscdr2);
+			pred &= MXC_CCM_CSCDR2_LCDIF_PIX_PRE_DIV_MASK;
+			pred = pred >> MXC_CCM_CSCDR2_LCDIF_PIX_PRE_DIV_OFFSET;
+
+			postd = readl(&imx_ccm->cscmr1);
+			postd &= MXC_CCM_CSCMR1_LCDIF_PIX_PODF_OFFSET;
+			postd = postd >> MXC_CCM_CBCMR_LCDIF1_PODF_OFFSET;
+		}
+	} else if (ifnum == 2) {
+		if (is_mx6sx()) {
+			pred = __raw_readl(&imx_ccm->cscdr2);
+			pred &= MXC_CCM_CSCDR2_LCDIF2_PRE_DIV_MASK;
+			pred = pred >> MXC_CCM_CSCDR2_LCDIF2_PRE_DIV_OFFSET;
+
+			postd = readl(&imx_ccm->cscmr1);
+			postd &= MXC_CCM_CSCMR1_LCDIF2_PODF_MASK;
+			postd = postd >> MXC_CCM_CSCMR1_LCDIF2_PODF_OFFSET;
+
+		} else {
+			goto if_err;
+		}
+	} else {
+		goto if_err;
+	}
+
+	return DIV_ROUND_UP_ULL((u64)pll_rate, (postd + 1) * (pred + 1));
+
+if_err:
+	debug("This chip not support lcd iterface %d\n", ifnum);
+	return 0;
+}
+
 static u32 get_cspi_clk(void)
 {
 	u32 reg, cspi_podf;
@@ -1273,6 +1327,10 @@ unsigned int mxc_get_clock(enum mxc_clock clk)
 		return get_usdhc_clk(3);
 	case MXC_SATA_CLK:
 		return get_ahb_clk();
+	case MXC_LCDIF1_CLK:
+		return get_lcd_clk(1);
+	case MXC_LCDIF2_CLK:
+		return get_lcd_clk(2);
 	default:
 		printf("Unsupported MXC CLK: %d\n", clk);
 		break;