[PATCH v4 2/6] clk: meson: add support for A1 PLL clock ops

[Jian Hu]

The A1 PLL design is different with previous SoCs. The PLL
internal analog modules Power-on sequence is different
with previous, and thus requires a strict register sequence to
enable the PLL.

Signed-off-by: Jian Hu <jian.hu@xxxxxxxxxxx>
---
 drivers/clk/meson/clk-pll.c | 21 +++++++++++++++++++++
 drivers/clk/meson/clk-pll.h |  1 +
 drivers/clk/meson/parm.h    |  1 +
 3 files changed, 23 insertions(+)

diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
index ddb1e5634739..4aff31a51589 100644
--- a/drivers/clk/meson/clk-pll.c
+++ b/drivers/clk/meson/clk-pll.c
@@ -318,6 +318,23 @@ static int meson_clk_pll_enable(struct clk_hw *hw)
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
 
+	/*
+	 * The A1 design is different with previous SoCs.The PLL
+	 * internal analog modules Power-on sequence is different with
+	 * previous, and thus requires a strict register sequence to
+	 * enable the PLL.
+	 */
+	if (MESON_PARM_APPLICABLE(&pll->current_en)) {
+		/* Enable the pll */
+		meson_parm_write(clk->map, &pll->en, 1);
+		udelay(10);
+		/* Enable the pll self-adaption module current */
+		meson_parm_write(clk->map, &pll->current_en, 1);
+		udelay(40);
+		meson_parm_write(clk->map, &pll->rst, 1);
+		meson_parm_write(clk->map, &pll->rst, 0);
+	}
+
 	/* do nothing if the PLL is already enabled */
 	if (clk_hw_is_enabled(hw))
 		return 0;
@@ -347,6 +364,10 @@ static void meson_clk_pll_disable(struct clk_hw *hw)
 
 	/* Disable the pll */
 	meson_parm_write(clk->map, &pll->en, 0);
+
+	/* Disable PLL internal self-adaption module current */
+	if (MESON_PARM_APPLICABLE(&pll->current_en))
+		meson_parm_write(clk->map, &pll->current_en, 0);
 }
 
 static int meson_clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
diff --git a/drivers/clk/meson/clk-pll.h b/drivers/clk/meson/clk-pll.h
index 367efd0f6410..30f039242a65 100644
--- a/drivers/clk/meson/clk-pll.h
+++ b/drivers/clk/meson/clk-pll.h
@@ -36,6 +36,7 @@ struct meson_clk_pll_data {
 	struct parm frac;
 	struct parm l;
 	struct parm rst;
+	struct parm current_en;
 	const struct reg_sequence *init_regs;
 	unsigned int init_count;
 	const struct pll_params_table *table;
diff --git a/drivers/clk/meson/parm.h b/drivers/clk/meson/parm.h
index 3c9ef1b505ce..c53fb26577e3 100644
--- a/drivers/clk/meson/parm.h
+++ b/drivers/clk/meson/parm.h
@@ -20,6 +20,7 @@
 	(((reg) & CLRPMASK(width, shift)) | ((val) << (shift)))
 
 #define MESON_PARM_APPLICABLE(p)		(!!((p)->width))
+#define MESON_PARM_CURRENT(p)			(!!((p)->width))
 
 struct parm {
 	u16	reg_off;
-- 
2.24.0