Modern meson PLL IPs are a little bit different from early known PLLs.
The main difference is located in the init/enable/disable sequences; the
rate logic is the same.
In A1 PLL, the PLL enable sequence is different, so add new optional pll
reg bits and use the new power-on sequence to enable the PLL:
1. enable the pll, delay for 10us
2. enable the pll self-adaption current module, delay for 40us
3. enable the lock detect module
Signed-off-by: Jian Hu <[email protected]>
Acked-by: Martin Blumenstingl <[email protected]>
Signed-off-by: Dmitry Rokosov <[email protected]>
---
drivers/clk/meson/clk-pll.c | 23 +++++++++++++++++++++++
drivers/clk/meson/clk-pll.h | 2 ++
2 files changed, 25 insertions(+)
diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
index 314ca945a4d0..56ec2210f1ad 100644
--- a/drivers/clk/meson/clk-pll.c
+++ b/drivers/clk/meson/clk-pll.c
@@ -358,6 +358,25 @@ static int meson_clk_pll_enable(struct clk_hw *hw)
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)) {
+ usleep_range(10, 20);
+ meson_parm_write(clk->map, &pll->current_en, 1);
+ usleep_range(40, 50);
+ };
+
+ 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;
@@ -375,6 +394,10 @@ 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 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;
--
2.36.0