[PATCH v2 2/2] clk: mediatek: Add MT8173 MMPLL change rate support

[James Liao]

MT8173 MMPLL frequency settings are different from common PLLs.
It needs different post divider settings for some ranges of frequency.
This patch add support for MT8173 MMPLL frequency setting, includes:

1. Add div-rate table for PLLs.
2. Increase the max ost divider setting from 3 (/8) to 4 (/16).

Signed-off-by: James Liao <jamesjj.liao at mediatek.com>
---
 drivers/clk/mediatek/clk-mt8173.c | 24 +++++++++++++++++++++---
 drivers/clk/mediatek/clk-mtk.h    |  6 ++++++
 drivers/clk/mediatek/clk-pll.c    | 18 +++++++++++++++---
 3 files changed, 42 insertions(+), 6 deletions(-)

diff --git a/drivers/clk/mediatek/clk-mt8173.c b/drivers/clk/mediatek/clk-mt8173.c
index 357b080..e3101e6 100644
--- a/drivers/clk/mediatek/clk-mt8173.c
+++ b/drivers/clk/mediatek/clk-mt8173.c
@@ -779,8 +779,9 @@ CLK_OF_DECLARE(mtk_pericfg, "mediatek,mt8173-pericfg", mtk_pericfg_init);
 
 #define CON0_MT8173_RST_BAR	BIT(24)
 
-#define PLL(_id, _name, _reg, _pwr_reg, _en_mask, _flags, _pcwbits, _pd_reg, _pd_shift, \
-			_tuner_reg, _pcw_reg, _pcw_shift) { \
+#define PLL_B(_id, _name, _reg, _pwr_reg, _en_mask, _flags, _pcwbits,	\
+			_pd_reg, _pd_shift, _tuner_reg, _pcw_reg,	\
+			_pcw_shift, _div_table) {			\
 		.id = _id,						\
 		.name = _name,						\
 		.reg = _reg,						\
@@ -795,14 +796,31 @@ CLK_OF_DECLARE(mtk_pericfg, "mediatek,mt8173-pericfg", mtk_pericfg_init);
 		.tuner_reg = _tuner_reg,				\
 		.pcw_reg = _pcw_reg,					\
 		.pcw_shift = _pcw_shift,				\
+		.div_table = _div_table,				\
 	}
 
+#define PLL(_id, _name, _reg, _pwr_reg, _en_mask, _flags, _pcwbits,	\
+			_pd_reg, _pd_shift, _tuner_reg, _pcw_reg,	\
+			_pcw_shift)					\
+		PLL_B(_id, _name, _reg, _pwr_reg, _en_mask, _flags, _pcwbits, \
+			_pd_reg, _pd_shift, _tuner_reg, _pcw_reg, _pcw_shift, \
+			NULL)
+
+static const struct mtk_pll_div_table mmpll_div_table[] = {
+	{ .div = 0, .freq = MT8173_PLL_FMAX },
+	{ .div = 1, .freq = 1000000000 },
+	{ .div = 2, .freq = 702000000 },
+	{ .div = 3, .freq = 253500000 },
+	{ .div = 4, .freq = 126750000 },
+	{ } /* sentinel */
+};
+
 static const struct mtk_pll_data plls[] = {
 	PLL(CLK_APMIXED_ARMCA15PLL, "armca15pll", 0x200, 0x20c, 0x00000001, 0, 21, 0x204, 24, 0x0, 0x204, 0),
 	PLL(CLK_APMIXED_ARMCA7PLL, "armca7pll", 0x210, 0x21c, 0x00000001, 0, 21, 0x214, 24, 0x0, 0x214, 0),
 	PLL(CLK_APMIXED_MAINPLL, "mainpll", 0x220, 0x22c, 0xf0000101, HAVE_RST_BAR, 21, 0x220, 4, 0x0, 0x224, 0),
 	PLL(CLK_APMIXED_UNIVPLL, "univpll", 0x230, 0x23c, 0xfe000001, HAVE_RST_BAR, 7, 0x230, 4, 0x0, 0x234, 14),
-	PLL(CLK_APMIXED_MMPLL, "mmpll", 0x240, 0x24c, 0x00000001, 0, 21, 0x244, 24, 0x0, 0x244, 0),
+	PLL_B(CLK_APMIXED_MMPLL, "mmpll", 0x240, 0x24c, 0x00000001, 0, 21, 0x244, 24, 0x0, 0x244, 0, mmpll_div_table),
 	PLL(CLK_APMIXED_MSDCPLL, "msdcpll", 0x250, 0x25c, 0x00000001, 0, 21, 0x250, 4, 0x0, 0x254, 0),
 	PLL(CLK_APMIXED_VENCPLL, "vencpll", 0x260, 0x26c, 0x00000001, 0, 21, 0x260, 4, 0x0, 0x264, 0),
 	PLL(CLK_APMIXED_TVDPLL, "tvdpll", 0x270, 0x27c, 0x00000001, 0, 21, 0x270, 4, 0x0, 0x274, 0),
diff --git a/drivers/clk/mediatek/clk-mtk.h b/drivers/clk/mediatek/clk-mtk.h
index 61035b9..fa0c1fe 100644
--- a/drivers/clk/mediatek/clk-mtk.h
+++ b/drivers/clk/mediatek/clk-mtk.h
@@ -134,6 +134,11 @@ struct clk_onecell_data *mtk_alloc_clk_data(unsigned int clk_num);
 
 #define HAVE_RST_BAR	BIT(0)
 
+struct mtk_pll_div_table {
+	u32 div;
+	unsigned long freq;
+};
+
 struct mtk_pll_data {
 	int id;
 	const char *name;
@@ -150,6 +155,7 @@ struct mtk_pll_data {
 	int pcwbits;
 	uint32_t pcw_reg;
 	int pcw_shift;
+	const struct mtk_pll_div_table *div_table;
 };
 
 void __init mtk_clk_register_plls(struct device_node *node,
diff --git a/drivers/clk/mediatek/clk-pll.c b/drivers/clk/mediatek/clk-pll.c
index 68af518..622e7b6 100644
--- a/drivers/clk/mediatek/clk-pll.c
+++ b/drivers/clk/mediatek/clk-pll.c
@@ -138,16 +138,28 @@ static void mtk_pll_calc_values(struct mtk_clk_pll *pll, u32 *pcw, u32 *postdiv,
 		u32 freq, u32 fin)
 {
 	unsigned long fmin = 1000 * MHZ;
+	const struct mtk_pll_div_table *div_table = pll->data->div_table;
 	u64 _pcw;
 	u32 val;
 
 	if (freq > pll->data->fmax)
 		freq = pll->data->fmax;
 
-	for (val = 0; val < 4; val++) {
+	if (div_table) {
+		if (freq > div_table[0].freq)
+			freq = div_table[0].freq;
+
+		for (val = 0; div_table[val + 1].freq != 0; val++) {
+			if (freq > div_table[val + 1].freq)
+				break;
+		}
 		*postdiv = 1 << val;
-		if (freq * *postdiv >= fmin)
-			break;
+	} else {
+		for (val = 0; val < 5; val++) {
+			*postdiv = 1 << val;
+			if ((u64)freq * *postdiv >= fmin)
+				break;
+		}
 	}
 
 	/* _pcw = freq * postdiv / fin * 2^pcwfbits */
-- 
1.8.1.1.dirty