[PATCH 12/15] drm/sun4i: Add support for second clock parent to DW HDMI PHY clk driver
From: Jernej Skrabec
Date: Sat May 19 2018 - 13:38:18 EST
Expand HDMI PHY clock driver to support second clock parent.
Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
---
drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h | 6 +-
drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c | 29 ++++++-
drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c | 90 ++++++++++++++++------
3 files changed, 98 insertions(+), 27 deletions(-)
diff --git a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
index 801a17222762..aadbe0a10b0c 100644
--- a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
+++ b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
@@ -98,7 +98,8 @@
#define SUN8I_HDMI_PHY_PLL_CFG1_LDO2_EN BIT(29)
#define SUN8I_HDMI_PHY_PLL_CFG1_LDO1_EN BIT(28)
#define SUN8I_HDMI_PHY_PLL_CFG1_HV_IS_33 BIT(27)
-#define SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL BIT(26)
+#define SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK BIT(26)
+#define SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_SHIFT 26
#define SUN8I_HDMI_PHY_PLL_CFG1_PLLEN BIT(25)
#define SUN8I_HDMI_PHY_PLL_CFG1_LDO_VSET(x) ((x) << 22)
#define SUN8I_HDMI_PHY_PLL_CFG1_UNKNOWN(x) ((x) << 20)
@@ -190,6 +191,7 @@ void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi *hdmi);
void sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy);
const struct dw_hdmi_phy_ops *sun8i_hdmi_phy_get_ops(void);
-int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device *dev);
+int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device *dev,
+ bool second_parent);
#endif /* _SUN8I_DW_HDMI_H_ */
diff --git a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
index deba47ed69d8..7a911f0a3ae3 100644
--- a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
+++ b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
@@ -183,7 +183,13 @@ static int sun8i_hdmi_phy_config_h3(struct dw_hdmi *hdmi,
regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_ANA_CFG1_REG,
SUN8I_HDMI_PHY_ANA_CFG1_TXEN_MASK, 0);
- regmap_write(phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG, pll_cfg1_init);
+ /*
+ * NOTE: We have to be careful not to overwrite PHY parent
+ * clock selection bit and clock divider.
+ */
+ regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG,
+ ~SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK,
+ pll_cfg1_init);
regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_PLL_CFG2_REG,
(u32)~SUN8I_HDMI_PHY_PLL_CFG2_PREDIV_MSK,
pll_cfg2_init);
@@ -352,6 +358,10 @@ static void sun8i_hdmi_phy_init_h3(struct sun8i_hdmi_phy *phy)
SUN8I_HDMI_PHY_ANA_CFG3_SCLEN |
SUN8I_HDMI_PHY_ANA_CFG3_SDAEN);
+ /* reset PLL clock configuration */
+ regmap_write(phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG, 0);
+ regmap_write(phy->regs, SUN8I_HDMI_PHY_PLL_CFG2_REG, 0);
+
/* set HW control of CEC pins */
regmap_write(phy->regs, SUN8I_HDMI_PHY_CEC_REG, 0);
@@ -481,18 +491,28 @@ int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi, struct device_node *node)
}
}
- ret = sun8i_phy_clk_create(phy, dev);
+ ret = sun8i_phy_clk_create(phy, dev,
+ phy->variant->has_second_pll);
if (ret) {
dev_err(dev, "Couldn't create the PHY clock\n");
goto err_put_clk_pll1;
}
+
+ /*
+ * Even though HDMI PHY clock doesn't have enable/disable
+ * handlers, we have to enable it. Otherwise it could happen
+ * that parent PLL is not enabled by clock framework in a
+ * highly unlikely event when parent PLL is used solely for
+ * HDMI PHY clock.
+ */
+ clk_prepare_enable(phy->clk_phy);
}
phy->rst_phy = of_reset_control_get_shared(node, "phy");
if (IS_ERR(phy->rst_phy)) {
dev_err(dev, "Could not get phy reset control\n");
ret = PTR_ERR(phy->rst_phy);
- goto err_put_clk_pll1;
+ goto err_disable_clk_phy;
}
ret = reset_control_deassert(phy->rst_phy);
@@ -523,6 +543,8 @@ int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi, struct device_node *node)
reset_control_assert(phy->rst_phy);
err_put_rst_phy:
reset_control_put(phy->rst_phy);
+err_disable_clk_phy:
+ clk_disable_unprepare(phy->clk_phy);
err_put_clk_pll1:
clk_put(phy->clk_pll1);
err_put_clk_pll0:
@@ -541,6 +563,7 @@ void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi *hdmi)
clk_disable_unprepare(phy->clk_mod);
clk_disable_unprepare(phy->clk_bus);
+ clk_disable_unprepare(phy->clk_phy);
reset_control_assert(phy->rst_phy);
diff --git a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c
index faea449812f8..a4d31fe3abff 100644
--- a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c
+++ b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c
@@ -22,35 +22,45 @@ static int sun8i_phy_clk_determine_rate(struct clk_hw *hw,
{
unsigned long rate = req->rate;
unsigned long best_rate = 0;
+ struct clk_hw *best_parent = NULL;
struct clk_hw *parent;
int best_div = 1;
- int i;
+ int i, p;
- parent = clk_hw_get_parent(hw);
-
- for (i = 1; i <= 16; i++) {
- unsigned long ideal = rate * i;
- unsigned long rounded;
-
- rounded = clk_hw_round_rate(parent, ideal);
+ for (p = 0; p < clk_hw_get_num_parents(hw); p++) {
+ parent = clk_hw_get_parent_by_index(hw, p);
+ if (!parent)
+ continue;
- if (rounded == ideal) {
- best_rate = rounded;
- best_div = i;
- break;
+ for (i = 1; i <= 16; i++) {
+ unsigned long ideal = rate * i;
+ unsigned long rounded;
+
+ rounded = clk_hw_round_rate(parent, ideal);
+
+ if (rounded == ideal) {
+ best_rate = rounded;
+ best_div = i;
+ best_parent = parent;
+ break;
+ }
+
+ if (!best_rate ||
+ abs(rate - rounded / i) <
+ abs(rate - best_rate / best_div)) {
+ best_rate = rounded;
+ best_div = i;
+ best_parent = parent;
+ }
}
- if (!best_rate ||
- abs(rate - rounded / i) <
- abs(rate - best_rate / best_div)) {
- best_rate = rounded;
- best_div = i;
- }
+ if (best_rate / best_div == rate)
+ break;
}
req->rate = best_rate / best_div;
req->best_parent_rate = best_rate;
- req->best_parent_hw = parent;
+ req->best_parent_hw = best_parent;
return 0;
}
@@ -95,22 +105,58 @@ static int sun8i_phy_clk_set_rate(struct clk_hw *hw, unsigned long rate,
return 0;
}
+static u8 sun8i_phy_clk_get_parent(struct clk_hw *hw)
+{
+ struct sun8i_phy_clk *priv = hw_to_phy_clk(hw);
+ u32 reg;
+
+ regmap_read(priv->phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG, ®);
+ reg = (reg & SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK) >>
+ SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_SHIFT;
+
+ return reg;
+}
+
+static int sun8i_phy_clk_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct sun8i_phy_clk *priv = hw_to_phy_clk(hw);
+
+ if (index > 1)
+ return -EINVAL;
+
+ regmap_update_bits(priv->phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG,
+ SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK,
+ index << SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_SHIFT);
+
+ return 0;
+}
+
static const struct clk_ops sun8i_phy_clk_ops = {
.determine_rate = sun8i_phy_clk_determine_rate,
.recalc_rate = sun8i_phy_clk_recalc_rate,
.set_rate = sun8i_phy_clk_set_rate,
+
+ .get_parent = sun8i_phy_clk_get_parent,
+ .set_parent = sun8i_phy_clk_set_parent,
};
-int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device *dev)
+int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device *dev,
+ bool second_parent)
{
struct clk_init_data init;
struct sun8i_phy_clk *priv;
- const char *parents[1];
+ const char *parents[2];
parents[0] = __clk_get_name(phy->clk_pll0);
if (!parents[0])
return -ENODEV;
+ if (second_parent) {
+ parents[1] = __clk_get_name(phy->clk_pll1);
+ if (!parents[1])
+ return -ENODEV;
+ }
+
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
@@ -118,7 +164,7 @@ int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device *dev)
init.name = "hdmi-phy-clk";
init.ops = &sun8i_phy_clk_ops;
init.parent_names = parents;
- init.num_parents = 1;
+ init.num_parents = second_parent ? 2 : 1;
init.flags = CLK_SET_RATE_PARENT;
priv->phy = phy;
--
2.17.0