[v6,2/5] clk: meson: add support for A1 PLL clock ops
diff mbox series

Message ID 20200116080440.118679-3-jian.hu@amlogic.com
State Superseded
Delegated to: Neil Armstrong
Headers show
Series
  • add Amlogic A1 clock controller driver
Related show

Commit Message

Jian Hu Jan. 16, 2020, 8:04 a.m. UTC
Compared with the previous SoCs, self-adaption current module
is newly added for A1, and there is no reset parm except the
fixed pll. In A1 PLL, the PLL enable sequence is different, using
the new power-on sequence to enable the PLL.

Signed-off-by: Jian Hu <jian.hu@amlogic.com>
---
 drivers/clk/meson/clk-pll.c | 47 +++++++++++++++++++++++++++++++------
 drivers/clk/meson/clk-pll.h |  2 ++
 2 files changed, 42 insertions(+), 7 deletions(-)

Comments

Martin Blumenstingl Jan. 18, 2020, 9:57 p.m. UTC | #1
Hi Jian,

thank you for the update!

On Thu, Jan 16, 2020 at 9:04 AM Jian Hu <jian.hu@amlogic.com> wrote:
>
> Compared with the previous SoCs, self-adaption current module
> is newly added for A1, and there is no reset parm except the
> fixed pll. In A1 PLL, the PLL enable sequence is different, using
> the new power-on sequence to enable the PLL.
>
> Signed-off-by: Jian Hu <jian.hu@amlogic.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

[...]
> @@ -323,13 +330,34 @@ static int meson_clk_pll_enable(struct clk_hw *hw)
>                 return 0;
>
>         /* Make sure the pll is in reset */
> -       meson_parm_write(clk->map, &pll->rst, 1);
> +       if (MESON_PARM_APPLICABLE(&pll->rst))
> +               meson_parm_write(clk->map, &pll->rst, 1);
>
>         /* Enable the pll */
>         meson_parm_write(clk->map, &pll->en, 1);
>
>         /* Take the pll out reset */
> -       meson_parm_write(clk->map, &pll->rst, 0);
> +       if (MESON_PARM_APPLICABLE(&pll->rst))
> +               meson_parm_write(clk->map, &pll->rst, 0);
> +
> +       /*
> +        * Compared with the previous SoCs, self-adaption current module
> +        * is newly added for A1, keep the new power-on sequence to enable the
> +        * PLL. The sequence is:
> +        * 1. enable the pll, delay for 10us
> +        * 2. enable the pll self-adaption current module, delay for 40us
> +        * 3. enable the lock detect module
> +        */
> +       if (MESON_PARM_APPLICABLE(&pll->current_en)) {
> +               udelay(10);
> +               meson_parm_write(clk->map, &pll->current_en, 1);
> +               udelay(40);
note to myself: first I thought that these have to be converted to ulseep_range
BUT: clk_enable can be called from atomic context, so the atomic
versions (udelay instead of usleep/usleep_range) are perfectly fine in
Jian's patch


Martin

Patch
diff mbox series

diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
index ddb1e5634739..10926291440f 100644
--- a/drivers/clk/meson/clk-pll.c
+++ b/drivers/clk/meson/clk-pll.c
@@ -283,10 +283,14 @@  static void meson_clk_pll_init(struct clk_hw *hw)
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
 
 	if (pll->init_count) {
-		meson_parm_write(clk->map, &pll->rst, 1);
+		if (MESON_PARM_APPLICABLE(&pll->rst))
+			meson_parm_write(clk->map, &pll->rst, 1);
+
 		regmap_multi_reg_write(clk->map, pll->init_regs,
 				       pll->init_count);
-		meson_parm_write(clk->map, &pll->rst, 0);
+
+		if (MESON_PARM_APPLICABLE(&pll->rst))
+			meson_parm_write(clk->map, &pll->rst, 0);
 	}
 }
 
@@ -295,8 +299,11 @@  static int meson_clk_pll_is_enabled(struct clk_hw *hw)
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
 
-	if (meson_parm_read(clk->map, &pll->rst) ||
-	    !meson_parm_read(clk->map, &pll->en) ||
+	if (MESON_PARM_APPLICABLE(&pll->rst) &&
+	    meson_parm_read(clk->map, &pll->rst))
+		return 0;
+
+	if (!meson_parm_read(clk->map, &pll->en) ||
 	    !meson_parm_read(clk->map, &pll->l))
 		return 0;
 
@@ -323,13 +330,34 @@  static int meson_clk_pll_enable(struct clk_hw *hw)
 		return 0;
 
 	/* Make sure the pll is in reset */
-	meson_parm_write(clk->map, &pll->rst, 1);
+	if (MESON_PARM_APPLICABLE(&pll->rst))
+		meson_parm_write(clk->map, &pll->rst, 1);
 
 	/* Enable the pll */
 	meson_parm_write(clk->map, &pll->en, 1);
 
 	/* Take the pll out reset */
-	meson_parm_write(clk->map, &pll->rst, 0);
+	if (MESON_PARM_APPLICABLE(&pll->rst))
+		meson_parm_write(clk->map, &pll->rst, 0);
+
+	/*
+	 * Compared with the previous SoCs, self-adaption current module
+	 * is newly added for A1, keep the new power-on sequence to enable the
+	 * PLL. The sequence is:
+	 * 1. enable the pll, delay for 10us
+	 * 2. enable the pll self-adaption current module, delay for 40us
+	 * 3. enable the lock detect module
+	 */
+	if (MESON_PARM_APPLICABLE(&pll->current_en)) {
+		udelay(10);
+		meson_parm_write(clk->map, &pll->current_en, 1);
+		udelay(40);
+	};
+
+	if (MESON_PARM_APPLICABLE(&pll->l_detect)) {
+		meson_parm_write(clk->map, &pll->l_detect, 1);
+		meson_parm_write(clk->map, &pll->l_detect, 0);
+	}
 
 	if (meson_clk_pll_wait_lock(hw))
 		return -EIO;
@@ -343,10 +371,15 @@  static void meson_clk_pll_disable(struct clk_hw *hw)
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
 
 	/* Put the pll is in reset */
-	meson_parm_write(clk->map, &pll->rst, 1);
+	if (MESON_PARM_APPLICABLE(&pll->rst))
+		meson_parm_write(clk->map, &pll->rst, 1);
 
 	/* Disable the pll */
 	meson_parm_write(clk->map, &pll->en, 0);
+
+	/* Disable PLL internal self-adaption current module */
+	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..a2228c0fdce5 100644
--- a/drivers/clk/meson/clk-pll.h
+++ b/drivers/clk/meson/clk-pll.h
@@ -36,6 +36,8 @@  struct meson_clk_pll_data {
 	struct parm frac;
 	struct parm l;
 	struct parm rst;
+	struct parm current_en;
+	struct parm l_detect;
 	const struct reg_sequence *init_regs;
 	unsigned int init_count;
 	const struct pll_params_table *table;