[U-Boot] [PATCH v3 3/4] ARM: EXYNOS: add exynos lcd clock interface

[U-Boot] [PATCH v3 3/4] ARM: EXYNOS: add exynos lcd clock interface

[Donghwa Lee]

To get lcd clock in EXYNOS display driver, added get_lcd_clk() interface.

Signed-off-by: Donghwa Lee <dh09.lee@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 arch/arm/cpu/armv7/exynos/clock.c      |   79 ++++++++++++++++++++++++++++++++
 arch/arm/include/asm/arch-exynos/clk.h |    2 +
 2 files changed, 81 insertions(+), 0 deletions(-)

diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
index 2f7048b..ecaa11e 100644
--- a/arch/arm/cpu/armv7/exynos/clock.c
+++ b/arch/arm/cpu/armv7/exynos/clock.c
@@ -414,6 +414,71 @@ static void exynos5_set_mmc_clk(int dev_index, unsigned int div)
 	writel(val, addr);
 }
 
+/* get_lcd_clk: return lcd clock frequency */
+static unsigned long exynos4_get_lcd_clk(void)
+{
+	struct exynos4_clock *clk =
+		(struct exynos4_clock *)samsung_get_base_clock();
+	unsigned long pclk, sclk;
+	unsigned int sel;
+	unsigned int ratio;
+
+	/*
+	 * CLK_SRC_LCD0
+	 * FIMD0_SEL [3:0]
+	 */
+	sel = readl(&clk->src_lcd0);
+	sel = sel & 0xf;
+
+	/*
+	 * 0x6: SCLK_MPLL
+	 * 0x7: SCLK_EPLL
+	 * 0x8: SCLK_VPLL
+	 */
+	if (sel == 0x6)
+		sclk = get_pll_clk(MPLL);
+	else if (sel == 0x7)
+		sclk = get_pll_clk(EPLL);
+	else if (sel == 0x8)
+		sclk = get_pll_clk(VPLL);
+	else
+		return 0;
+
+	/*
+	 * CLK_DIV_LCD0
+	 * FIMD0_RATIO [3:0]
+	 */
+	ratio = readl(&clk->div_lcd0);
+	ratio = ratio & 0xf;
+
+	pclk = sclk / (ratio + 1);
+
+	return pclk;
+}
+
+void exynos4_set_lcd_clk(void)
+{
+	struct exynos4_clock *clk =
+	    (struct exynos4_clock *)samsung_get_base_clock();
+	unsigned int cfg = 0;
+
+	/* set lcd src clock 0x6: SCLK_VPLL */
+	cfg = readl(&clk->src_lcd0);
+	cfg &= ~(0xf);
+	cfg |= 0x6;
+	writel(cfg, &clk->src_lcd0);
+
+	/* Gating all clocks for FIMD0 */
+	cfg = readl(&clk->gate_ip_lcd0);
+	cfg |= 1 << 0;
+	writel(cfg, &clk->gate_ip_lcd0);
+
+	/* set fimd ratio */
+	cfg &= ~(0xf);
+	cfg |= 0x1;
+	writel(cfg, &clk->div_lcd0);
+}
+
 unsigned long get_pll_clk(int pllreg)
 {
 	if (cpu_is_exynos5())
@@ -453,3 +518,17 @@ void set_mmc_clk(int dev_index, unsigned int div)
 	else
 		exynos4_set_mmc_clk(dev_index, div);
 }
+
+unsigned long get_lcd_clk(void)
+{
+	if (cpu_is_exynos4())
+		return exynos4_get_lcd_clk();
+	else
+		return 0;
+}
+
+void set_lcd_clk(void)
+{
+	if (cpu_is_exynos4())
+		exynos4_set_lcd_clk();
+}
diff --git a/arch/arm/include/asm/arch-exynos/clk.h b/arch/arm/include/asm/arch-exynos/clk.h
index ff0f641..cf00dea 100644
--- a/arch/arm/include/asm/arch-exynos/clk.h
+++ b/arch/arm/include/asm/arch-exynos/clk.h
@@ -33,5 +33,7 @@ unsigned long get_arm_clk(void);
 unsigned long get_pwm_clk(void);
 unsigned long get_uart_clk(int dev_index);
 void set_mmc_clk(int dev_index, unsigned int div);
+unsigned long get_lcd_clk(void);
+void set_lcd_clk(void);
 
 #endif
-- 
1.7.4.1