1 files changed, 127 insertions, 0 deletions

diff --git a/drivers/clk/zte/clk.c b/drivers/clk/zte/clk.c
index c4c1251bc1e7..878d879b23ff 100644
--- a/drivers/clk/zte/clk.c
+++ b/drivers/clk/zte/clk.c
@@ -9,6 +9,7 @@
 
 #include <linux/clk-provider.h>
 #include <linux/err.h>
+#include <linux/gcd.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/slab.h>
@@ -310,3 +311,129 @@ struct clk *clk_register_zx_audio(const char *name,
 
 	return clk;
 }
+
+#define CLK_AUDIO_DIV_FRAC	BIT(0)
+#define CLK_AUDIO_DIV_INT	BIT(1)
+#define CLK_AUDIO_DIV_UNCOMMON	BIT(1)
+
+#define CLK_AUDIO_DIV_FRAC_NSHIFT	16
+#define CLK_AUDIO_DIV_INT_FRAC_RE	BIT(16)
+#define CLK_AUDIO_DIV_INT_FRAC_MAX	(0xffff)
+#define CLK_AUDIO_DIV_INT_FRAC_MIN	(0x2)
+#define CLK_AUDIO_DIV_INT_INT_SHIFT	24
+#define CLK_AUDIO_DIV_INT_INT_WIDTH	4
+
+struct zx_clk_audio_div_table {
+	unsigned long rate;
+	unsigned int int_reg;
+	unsigned int frac_reg;
+};
+
+#define to_clk_zx_audio_div(_hw) container_of(_hw, struct clk_zx_audio_divider, hw)
+
+static unsigned long audio_calc_rate(struct clk_zx_audio_divider *audio_div,
+				     u32 reg_frac, u32 reg_int,
+				     unsigned long parent_rate)
+{
+	unsigned long rate, m, n;
+
+	m = reg_frac & 0xffff;
+	n = (reg_frac >> 16) & 0xffff;
+
+	m = (reg_int & 0xffff) * n + m;
+	rate = (parent_rate * n) / m;
+
+	return rate;
+}
+
+static void audio_calc_reg(struct clk_zx_audio_divider *audio_div,
+			   struct zx_clk_audio_div_table *div_table,
+			   unsigned long rate, unsigned long parent_rate)
+{
+	unsigned int reg_int, reg_frac;
+	unsigned long m, n, div;
+
+	reg_int = parent_rate / rate;
+
+	if (reg_int > CLK_AUDIO_DIV_INT_FRAC_MAX)
+		reg_int = CLK_AUDIO_DIV_INT_FRAC_MAX;
+	else if (reg_int < CLK_AUDIO_DIV_INT_FRAC_MIN)
+		reg_int = 0;
+	m = parent_rate - rate * reg_int;
+	n = rate;
+
+	div = gcd(m, n);
+	m = m / div;
+	n = n / div;
+
+	if ((m >> 16) || (n >> 16)) {
+		if (m > n) {
+			n = n * 0xffff / m;
+			m = 0xffff;
+		} else {
+			m = m * 0xffff / n;
+			n = 0xffff;
+		}
+	}
+	reg_frac = m | (n << 16);
+
+	div_table->rate = parent_rate * n / (reg_int * n + m);
+	div_table->int_reg = reg_int;
+	div_table->frac_reg = reg_frac;
+}
+
+static unsigned long zx_audio_div_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
+	u32 reg_frac, reg_int;
+
+	reg_frac = readl_relaxed(zx_audio_div->reg_base);
+	reg_int = readl_relaxed(zx_audio_div->reg_base + 0x4);
+
+	return audio_calc_rate(zx_audio_div, reg_frac, reg_int, parent_rate);
+}
+
+static long zx_audio_div_round_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long *prate)
+{
+	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
+	struct zx_clk_audio_div_table divt;
+
+	audio_calc_reg(zx_audio_div, &divt, rate, *prate);
+
+	return audio_calc_rate(zx_audio_div, divt.frac_reg, divt.int_reg, *prate);
+}
+
+static int zx_audio_div_set_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long parent_rate)
+{
+	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
+	struct zx_clk_audio_div_table divt;
+	unsigned int val;
+
+	audio_calc_reg(zx_audio_div, &divt, rate, parent_rate);
+	if (divt.rate != rate)
+		pr_debug("the real rate is:%ld", divt.rate);
+
+	writel_relaxed(divt.frac_reg, zx_audio_div->reg_base);
+
+	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
+	val &= ~0xffff;
+	val |= divt.int_reg | CLK_AUDIO_DIV_INT_FRAC_RE;
+	writel_relaxed(val, zx_audio_div->reg_base + 0x4);
+
+	mdelay(1);
+
+	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
+	val &= ~CLK_AUDIO_DIV_INT_FRAC_RE;
+	writel_relaxed(val, zx_audio_div->reg_base + 0x4);
+
+	return 0;
+}
+
+const struct clk_ops zx_audio_div_ops = {
+	.recalc_rate = zx_audio_div_recalc_rate,
+	.round_rate = zx_audio_div_round_rate,
+	.set_rate = zx_audio_div_set_rate,
+};