MLK-12437-1 mx6sx: Add support for LVDS display

The i.MX6SX uses a LVDS bridge to mux to the LCDIF interface. Implmement a
function for this muxing. So that on 6SX we can use a LVDS display.

Signed-off-by: Ye Li <ye.li@nxp.com>
(cherry picked from commit 763658d9b497e44b7411581da592ef5b522e9cc9)

2 files changed, 63 insertions, 1 deletions

diff --git a/arch/arm/cpu/armv7/mx6/clock.c b/arch/arm/cpu/armv7/mx6/clock.c
index 84bc213..4614a1f 100644
--- a/arch/arm/cpu/armv7/mx6/clock.c
+++ b/arch/arm/cpu/armv7/mx6/clock.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2010-2011 Freescale Semiconductor, Inc.
+ * Copyright (C) 2010-2016 Freescale Semiconductor, Inc.
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */
@@ -850,6 +850,65 @@ int enable_lcdif_clock(u32 base_addr, bool enable)
 
 	return 0;
 }
+
+int enable_lvds_bridge(u32 lcd_base_addr)
+{
+	u32 reg = 0;
+	struct iomuxc *iomux = (struct iomuxc *)IOMUXC_BASE_ADDR;
+
+	if (is_cpu_type(MXC_CPU_MX6SX)) {
+		if ((lcd_base_addr != LCDIF1_BASE_ADDR) &&
+		    (lcd_base_addr != LCDIF2_BASE_ADDR)) {
+			puts("Wrong LCD interface!\n");
+			return -EINVAL;
+		}
+	} else {
+		debug("This chip not support lvds bridge!\n");
+		return 0;
+	}
+
+	/* Turn on LDB DI0 clocks */
+	reg = readl(&imx_ccm->CCGR3);
+	reg |=  MXC_CCM_CCGR3_LDB_DI0_MASK;
+	writel(reg, &imx_ccm->CCGR3);
+
+	/* set LDB DI0 clk select to 011 PLL2 PFD3 200M*/
+	reg = readl(&imx_ccm->cs2cdr);
+	reg &= ~MXC_CCM_CS2CDR_LDB_DI0_CLK_SEL_MASK;
+	reg |= (3 << MXC_CCM_CS2CDR_LDB_DI0_CLK_SEL_OFFSET);
+	writel(reg, &imx_ccm->cs2cdr);
+
+	reg = readl(&imx_ccm->cscmr2);
+	reg |= MXC_CCM_CSCMR2_LDB_DI0_IPU_DIV;
+	writel(reg, &imx_ccm->cscmr2);
+
+	/* set LDB DI0 clock for LCDIF PIX clock */
+	reg = readl(&imx_ccm->cscdr2);
+	if (lcd_base_addr == LCDIF1_BASE_ADDR) {
+		reg &= ~MXC_CCM_CSCDR2_LCDIF1_CLK_SEL_MASK;
+		reg |= (0x3 << MXC_CCM_CSCDR2_LCDIF1_CLK_SEL_OFFSET);
+	} else {
+		reg &= ~MXC_CCM_CSCDR2_LCDIF2_CLK_SEL_MASK;
+		reg |= (0x3 << MXC_CCM_CSCDR2_LCDIF2_CLK_SEL_OFFSET);
+	}
+	writel(reg, &imx_ccm->cscdr2);
+
+	reg = IOMUXC_GPR2_DI0_VS_POLARITY_ACTIVE_LOW
+		| IOMUXC_GPR2_BIT_MAPPING_CH0_SPWG
+		| IOMUXC_GPR2_DATA_WIDTH_CH0_18BIT
+		| IOMUXC_GPR2_LVDS_CH0_MODE_ENABLED_DI0;
+	writel(reg, &iomux->gpr[6]);
+
+	reg = readl(&iomux->gpr[5]);
+	if (lcd_base_addr == LCDIF1_BASE_ADDR)
+		reg &= ~0x8;  /* MUX LVDS to LCDIF1 */
+	else
+		reg |= 0x8; /* MUX LVDS to LCDIF2 */
+	writel(reg, &iomux->gpr[5]);
+
+	return 0;
+}
+
 #endif
 
 #ifdef CONFIG_FSL_QSPI
diff --git a/arch/arm/include/asm/arch-mx6/clock.h b/arch/arm/include/asm/arch-mx6/clock.h
index 2d9c45e..d27d49b 100644
--- a/arch/arm/include/asm/arch-mx6/clock.h
+++ b/arch/arm/include/asm/arch-mx6/clock.h
@@ -2,6 +2,8 @@
  * (C) Copyright 2009
  * Stefano Babic, DENX Software Engineering, sbabic@denx.de.
  *
+ * Copyright (C) 2014-2016 Freescale Semiconductor, Inc.
+ *
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
@@ -75,6 +77,7 @@ void enable_ipu_clock(void);
 int enable_fec_anatop_clock(int fec_id, enum enet_freq freq);
 void enable_enet_clk(unsigned char enable);
 int enable_lcdif_clock(u32 base_addr, bool enable);
+int enable_lvds_bridge(u32 lcd_base_addr);
 void enable_qspi_clk(int qspi_num);
 void enable_thermal_clk(void);
 void mxs_set_lcdclk(u32 base_addr, u32 freq);