Hi Sean,
On 5/8/22 20:21, Sean Anderson wrote:
On 4/26/22 8:37 AM, Patrick Delaunay wrote:
Add the counter of the PLL user n_pll_cons managed by the 2 functions
stm32_usbphyc_pll_enable / stm32_usbphyc_pll_disable.
This counter allow to remove the function stm32_usbphyc_is_init
and it is a preliminary step for ck_usbo_48m introduction.
Is it necessary to disable this clock before booting to Linux? If it
isn't,
then perhaps it is simpler to just not disable the clock.
--Sean
No, it is not necessary, we only need to enable the clock for the first
user.
I copy the clock behavior from kernel,
but I agree that can be simpler.
Amelie any notice about this point ?
Do you prefer that I kept the behavior - same as kernel driver - or I
simplify the U-Boot driver ?
Patrick
Signed-off-by: Patrick Delaunay <patrick.delau...@foss.st.com>
---
drivers/phy/phy-stm32-usbphyc.c | 76 +++++++++++++++++++++------------
1 file changed, 48 insertions(+), 28 deletions(-)
diff --git a/drivers/phy/phy-stm32-usbphyc.c
b/drivers/phy/phy-stm32-usbphyc.c
index 9c1dcfae52..16c8799eca 100644
--- a/drivers/phy/phy-stm32-usbphyc.c
+++ b/drivers/phy/phy-stm32-usbphyc.c
@@ -65,6 +65,7 @@ struct stm32_usbphyc {
bool init;
bool powered;
} phys[MAX_PHYS];
+ int n_pll_cons;
};
static void stm32_usbphyc_get_pll_params(u32 clk_rate,
@@ -124,18 +125,6 @@ static int stm32_usbphyc_pll_init(struct
stm32_usbphyc *usbphyc)
return 0;
}
-static bool stm32_usbphyc_is_init(struct stm32_usbphyc *usbphyc)
-{
- int i;
-
- for (i = 0; i < MAX_PHYS; i++) {
- if (usbphyc->phys[i].init)
- return true;
- }
-
- return false;
-}
-
static bool stm32_usbphyc_is_powered(struct stm32_usbphyc *usbphyc)
{
int i;
@@ -148,18 +137,17 @@ static bool stm32_usbphyc_is_powered(struct
stm32_usbphyc *usbphyc)
return false;
}
-static int stm32_usbphyc_phy_init(struct phy *phy)
+static int stm32_usbphyc_pll_enable(struct stm32_usbphyc *usbphyc)
{
- struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
- struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
bool pllen = readl(usbphyc->base + STM32_USBPHYC_PLL) & PLLEN ?
true : false;
int ret;
- dev_dbg(phy->dev, "phy ID = %lu\n", phy->id);
- /* Check if one phy port has already configured the pll */
- if (pllen && stm32_usbphyc_is_init(usbphyc))
- goto initialized;
+ /* Check if one consumer has already configured the pll */
+ if (pllen && usbphyc->n_pll_cons) {
+ usbphyc->n_pll_cons++;
+ return 0;
+ }
if (usbphyc->vdda1v1) {
ret = regulator_set_enable(usbphyc->vdda1v1, true);
@@ -190,23 +178,19 @@ static int stm32_usbphyc_phy_init(struct phy *phy)
if (!(readl(usbphyc->base + STM32_USBPHYC_PLL) & PLLEN))
return -EIO;
-initialized:
- usbphyc_phy->init = true;
+ usbphyc->n_pll_cons++;
return 0;
}
-static int stm32_usbphyc_phy_exit(struct phy *phy)
+static int stm32_usbphyc_pll_disable(struct stm32_usbphyc *usbphyc)
{
- struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
- struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
int ret;
- dev_dbg(phy->dev, "phy ID = %lu\n", phy->id);
- usbphyc_phy->init = false;
+ usbphyc->n_pll_cons--;
- /* Check if other phy port requires pllen */
- if (stm32_usbphyc_is_init(usbphyc))
+ /* Check if other consumer requires pllen */
+ if (usbphyc->n_pll_cons)
return 0;
clrbits_le32(usbphyc->base + STM32_USBPHYC_PLL, PLLEN);
@@ -235,6 +219,42 @@ static int stm32_usbphyc_phy_exit(struct phy *phy)
return 0;
}
+static int stm32_usbphyc_phy_init(struct phy *phy)
+{
+ struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
+ struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
+ int ret;
+
+ dev_dbg(phy->dev, "phy ID = %lu\n", phy->id);
+ if (usbphyc_phy->init)
+ return 0;
+
+ ret = stm32_usbphyc_pll_enable(usbphyc);
+ if (ret)
+ return log_ret(ret);
+
+ usbphyc_phy->init = true;
+
+ return 0;
+}
+
+static int stm32_usbphyc_phy_exit(struct phy *phy)
+{
+ struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
+ struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
+ int ret;
+
+ dev_dbg(phy->dev, "phy ID = %lu\n", phy->id);
+ if (!usbphyc_phy->init)
+ return 0;
+
+ ret = stm32_usbphyc_pll_disable(usbphyc);
+
+ usbphyc_phy->init = false;
+
+ return log_ret(ret);
+}
+
static int stm32_usbphyc_phy_power_on(struct phy *phy)
{
struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
