[U-Boot] [PATCH 8/9] EXYNOS: Add clock for I2S

Rajeshwari Shinde rajeshwari.s at samsung.com
Tue Aug 14 07:45:31 CEST 2012


This patch adds clock support for I2S

Signed-off-by: R. Chandrasekar <rcsekar at samsung.com>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s at samsung.com>
---
 arch/arm/cpu/armv7/exynos/clock.c        |  119 ++++++++++++++++++++++++++++++
 arch/arm/include/asm/arch-exynos/clk.h   |    3 +
 arch/arm/include/asm/arch-exynos/clock.h |   29 +++++++
 3 files changed, 151 insertions(+), 0 deletions(-)

diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
index 2aa511e..ad47d22 100644
--- a/arch/arm/cpu/armv7/exynos/clock.c
+++ b/arch/arm/cpu/armv7/exynos/clock.c
@@ -26,6 +26,16 @@
 #include <asm/arch/clock.h>
 #include <asm/arch/clk.h>
 
+/* Epll Clock division values to achive different frequency output */
+static struct st_epll_con_val epll_div[] = {
+	{ 192000000, 0, 48, 3, 1, 0 },
+	{ 180000000, 0, 45, 3, 1, 0 },
+	{  73728000, 1, 73, 3, 3, 47710 },
+	{  67737600, 1, 90, 4, 3, 20762 },
+	{  49152000, 0, 49, 3, 3, 9961 },
+	{  45158400, 0, 45, 3, 3, 10381 },
+	{ 180633600, 0, 45, 3, 1, 10381 }
+};
 /* exynos4: return pll clock frequency */
 static unsigned long exynos4_get_pll_clk(int pllreg)
 {
@@ -744,6 +754,92 @@ static int exynos5_spi_set_clock_rate(enum periph_id periph_id,
 	return 0;
 }
 
+int exynos5_clock_epll_set_rate(unsigned long rate)
+{
+	unsigned int epll_con, epll_con_k;
+	unsigned int i;
+	unsigned int lockcnt;
+	unsigned int start;
+	struct exynos5_clock *clk =
+		(struct exynos5_clock *)samsung_get_base_clock();
+
+	epll_con = readl(&clk->epll_con0);
+	epll_con &= ~((EPLL_CON0_LOCK_DET_EN_MASK <<
+			EPLL_CON0_LOCK_DET_EN_SHIFT) |
+		EPLL_CON0_MDIV_MASK << EPLL_CON0_MDIV_SHIFT |
+		EPLL_CON0_PDIV_MASK << EPLL_CON0_PDIV_SHIFT |
+		EPLL_CON0_SDIV_MASK << EPLL_CON0_SDIV_SHIFT);
+
+	for (i = 0; i < ARRAY_SIZE(epll_div); i++) {
+		if (epll_div[i].freq_out == rate)
+			break;
+	}
+
+	if (i == ARRAY_SIZE(epll_div))
+		return -1;
+
+	epll_con_k = epll_div[i].k_dsm << 0;
+	epll_con |= epll_div[i].en_lock_det << EPLL_CON0_LOCK_DET_EN_SHIFT;
+	epll_con |= epll_div[i].m_div << EPLL_CON0_MDIV_SHIFT;
+	epll_con |= epll_div[i].p_div << EPLL_CON0_PDIV_SHIFT;
+	epll_con |= epll_div[i].s_div << EPLL_CON0_SDIV_SHIFT;
+
+	/*
+	 * Required period ( in cycles) to genarate a stable clock output.
+	 * The maximum clock time can be up to 3000 * PDIV cycles of PLLs
+	 * frequency input (as per spec)
+	 */
+	lockcnt = 3000 * epll_div[i].p_div;
+
+	writel(lockcnt, &clk->epll_lock);
+	writel(epll_con, &clk->epll_con0);
+	writel(epll_con_k, &clk->epll_con1);
+
+	start = get_timer(0);
+
+	 while (!(readl(&clk->epll_con0) &
+			(0x1 << EXYNOS5_EPLLCON0_LOCKED_SHIFT))) {
+		if (get_timer(start) > TIMEOUT_EPLL_LOCK) {
+			debug("%s: Timeout waiting for EPLL lock\n", __func__);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+void exynos5_clock_select_i2s_clk_source(void)
+{
+	struct exynos5_clock *clk =
+		(struct exynos5_clock *)samsung_get_base_clock();
+
+	clrsetbits_le32(&clk->src_peric1, AUDIO1_SEL_MASK,
+			(CLK_SRC_SCLK_EPLL));
+}
+
+int exynos5_clock_set_i2s_clk_prescaler(unsigned int src_frq,
+					unsigned int dst_frq)
+{
+	struct exynos5_clock *clk =
+		(struct exynos5_clock *)samsung_get_base_clock();
+	unsigned int div;
+
+	if ((dst_frq == 0) || (src_frq == 0)) {
+		debug("%s: Invalid requency input for prescaler\n", __func__);
+		debug("src frq = %d des frq = %d ", src_frq, dst_frq);
+		return -1;
+	}
+
+	div = (src_frq / dst_frq);
+	if (div > AUDIO_1_RATIO_MASK) {
+		debug("%s: Frequency ratio is out of range\n", __func__);
+		debug("src frq = %d des frq = %d ", src_frq, dst_frq);
+		return -1;
+	}
+	clrsetbits_le32(&clk->div_peric4, AUDIO_1_RATIO_MASK,
+				(div & AUDIO_1_RATIO_MASK));
+	return 0;
+}
+
 unsigned long get_pll_clk(int pllreg)
 {
 	if (cpu_is_exynos5())
@@ -821,3 +917,26 @@ int spi_set_clock_rate(enum periph_id periph_id, unsigned int rate)
 	else
 		return 0;
 }
+
+int clock_set_i2s_clk_prescaler(unsigned int src_frq, unsigned int dst_frq)
+{
+
+	if (cpu_is_exynos5())
+		return exynos5_clock_set_i2s_clk_prescaler(src_frq, dst_frq);
+	else
+		return 0;
+}
+
+void clock_select_i2s_clk_source(void)
+{
+	if (cpu_is_exynos5())
+		exynos5_clock_select_i2s_clk_source();
+}
+
+int clock_epll_set_rate(unsigned long rate)
+{
+	if (cpu_is_exynos5())
+		return exynos5_clock_epll_set_rate(rate);
+	else
+		return 0;
+}
diff --git a/arch/arm/include/asm/arch-exynos/clk.h b/arch/arm/include/asm/arch-exynos/clk.h
index 4e51402..f32c634 100644
--- a/arch/arm/include/asm/arch-exynos/clk.h
+++ b/arch/arm/include/asm/arch-exynos/clk.h
@@ -41,4 +41,7 @@ unsigned long get_lcd_clk(void);
 void set_lcd_clk(void);
 void set_mipi_clk(void);
 int spi_set_clock_rate(enum periph_id periph_id, unsigned int rate);
+void clock_select_i2s_clk_source(void);
+int clock_set_i2s_clk_prescaler(unsigned int src_frq, unsigned int dst_frq);
+int clock_epll_set_rate(unsigned long rate);
 #endif
diff --git a/arch/arm/include/asm/arch-exynos/clock.h b/arch/arm/include/asm/arch-exynos/clock.h
index fce38ef..1df49a9 100644
--- a/arch/arm/include/asm/arch-exynos/clock.h
+++ b/arch/arm/include/asm/arch-exynos/clock.h
@@ -595,9 +595,38 @@ struct exynos5_clock {
 	unsigned int	pll_div2_sel;
 	unsigned char	res123[0xf5d8];
 };
+
+/* structure for epll configuration used in audio clock configuration */
+struct st_epll_con_val {
+	unsigned int freq_out;		/* frequency out */
+	unsigned int en_lock_det;	/* enable lock detect */
+	unsigned int m_div;		/* m divider value */
+	unsigned int p_div;		/* p divider value */
+	unsigned int s_div;		/* s divider value */
+	unsigned int k_dsm;		/* k value of delta signal modulator */
+};
 #endif
 
 #define MPLL_FOUT_SEL_SHIFT	4
+#define EXYNOS5_EPLLCON0_LOCKED_SHIFT	29  /* EPLL Locked bit position*/
+#define TIMEOUT_EPLL_LOCK		1000
+
+#define AUDIO_0_RATIO_MASK		0x0f
+#define AUDIO_1_RATIO_MASK		0x0f
+
+#define AUDIO1_SEL_MASK			0xf
+#define CLK_SRC_SCLK_EPLL		0x7
+
+/* CON0 bit-fields */
+#define EPLL_CON0_MDIV_MASK		0x1ff
+#define EPLL_CON0_PDIV_MASK		0x3f
+#define EPLL_CON0_SDIV_MASK		0x7
+#define EPLL_CON0_MDIV_SHIFT		16
+#define EPLL_CON0_PDIV_SHIFT		8
+#define EPLL_CON0_SDIV_SHIFT		0
+#define EPLL_CON0_LOCK_DET_EN_SHIFT	28
+#define EPLL_CON0_LOCK_DET_EN_MASK	1
+
 #define MPLL_FOUT_SEL_MASK	0x1
 #define BPLL_FOUT_SEL_SHIFT	0
 #define BPLL_FOUT_SEL_MASK	0x1
-- 
1.7.4.4



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