[PATCH v2 02/10] clk: qcom: Add support for alpha pll hwfsm ops

Rajendra Nayak
2016-08-11T08:44:40Z

Add support to enable/disable the alpha pll using hwfsm

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
---
drivers/clk/qcom/clk-alpha-pll.c | 109 ++++++++++++++++++++++++++++++++++-----
drivers/clk/qcom/clk-alpha-pll.h | 1 +
2 files changed, 98 insertions(+), 12 deletions(-)

diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
index e6a03ea..bae31f9 100644
--- a/drivers/clk/qcom/clk-alpha-pll.c
+++ b/drivers/clk/qcom/clk-alpha-pll.c
@@ -62,9 +62,10 @@
#define to_clk_alpha_pll_postdiv(_hw) container_of(to_clk_regmap(_hw), \
struct clk_alpha_pll_postdiv, clkr)

-static int wait_for_pll(struct clk_alpha_pll *pll)
+static int wait_for_pll(struct clk_alpha_pll *pll, u32 mask, bool inverse,
+ const char *action)
{
- u32 val, mask, off;
+ u32 val, off;
int count;
int ret;
const char *name = clk_hw_get_name(&pll->clkr.hw);
@@ -74,26 +75,101 @@ static int wait_for_pll(struct clk_alpha_pll *pll)
if (ret)
return ret;

- if (val & PLL_VOTE_FSM_ENA)
- mask = PLL_ACTIVE_FLAG;
- else
- mask = PLL_LOCK_DET;
-
- /* Wait for pll to enable. */
for (count = 100; count > 0; count--) {
ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
if (ret)
return ret;
- if ((val & mask) == mask)
+ if (inverse && (val & mask))
+ return 0;
+ else if ((val & mask) == mask)
return 0;

udelay(1);
}

- WARN(1, "%s didn't enable after voting for it!\n", name);
+ WARN(1, "%s failed to %s!\n", name, action);
return -ETIMEDOUT;
}

+static int wait_for_pll_enable(struct clk_alpha_pll *pll, u32 mask)
+{
+ return wait_for_pll(pll, mask, 0, "enable");
+}
+
+static int wait_for_pll_disable(struct clk_alpha_pll *pll, u32 mask)
+{
+ return wait_for_pll(pll, mask, 1, "disable");
+}
+
+static int wait_for_pll_offline(struct clk_alpha_pll *pll, u32 mask)
+{
+ return wait_for_pll(pll, mask, 0, "offline");
+}
+
+/* alpha pll with hwfsm support */
+#define PLL_OFFLINE_REQ BIT(7)
+#define PLL_FSM_ENA BIT(20)
+#define PLL_OFFLINE_ACK BIT(28)
+#define PLL_ACTIVE_FLAG BIT(30)
+
+static int clk_alpha_pll_hwfsm_enable(struct clk_hw *hw)
+{
+ int ret;
+ u32 val, off;
+ struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
+
+ off = pll->offset;
+ ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
+ if (ret)
+ return ret;
+
+ /* Enable HW FSM mode, clear OFFLINE request */
+ val |= PLL_FSM_ENA;
+ val &= ~PLL_OFFLINE_REQ;
+ ret = regmap_write(pll->clkr.regmap, off + PLL_MODE, val);
+ if (ret)
+ return ret;
+
+ /* Make sure enable request goes through before waiting for update */
+ mb();
+
+ ret = wait_for_pll_enable(pll, PLL_ACTIVE_FLAG);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static void clk_alpha_pll_hwfsm_disable(struct clk_hw *hw)
+{
+ int ret;
+ u32 val, off;
+ struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
+
+ off = pll->offset;
+ ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
+ if (ret)
+ return;
+
+ /* Request PLL_OFFLINE and wait for ack */
+ ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
+ PLL_OFFLINE_REQ, PLL_OFFLINE_REQ);
+ if (ret)
+ return;
+
+ ret = wait_for_pll_offline(pll, PLL_OFFLINE_ACK);
+ if (ret)
+ return;
+
+ /* Disable hwfsm */
+ ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
+ PLL_FSM_ENA, 0);
+ if (ret)
+ return;
+
+ wait_for_pll_disable(pll, PLL_ACTIVE_FLAG);
+}
+
static int clk_alpha_pll_enable(struct clk_hw *hw)
{
int ret;
@@ -112,7 +188,7 @@ static int clk_alpha_pll_enable(struct clk_hw *hw)
ret = clk_enable_regmap(hw);
if (ret)
return ret;
- return wait_for_pll(pll);
+ return wait_for_pll_enable(pll, PLL_ACTIVE_FLAG);
}

/* Skip if already enabled */
@@ -136,7 +212,7 @@ static int clk_alpha_pll_enable(struct clk_hw *hw)
if (ret)
return ret;

- ret = wait_for_pll(pll);
+ ret = wait_for_pll_enable(pll, PLL_LOCK_DET);
if (ret)
return ret;

@@ -300,6 +376,15 @@ const struct clk_ops clk_alpha_pll_ops = {
};
EXPORT_SYMBOL_GPL(clk_alpha_pll_ops);

+const struct clk_ops clk_alpha_pll_hwfsm_ops = {
+ .enable = clk_alpha_pll_hwfsm_enable,
+ .disable = clk_alpha_pll_hwfsm_disable,
+ .recalc_rate = clk_alpha_pll_recalc_rate,
+ .round_rate = clk_alpha_pll_round_rate,
+ .set_rate = clk_alpha_pll_set_rate,
+};
+EXPORT_SYMBOL_GPL(clk_alpha_pll_hwfsm_ops);
+
static unsigned long
clk_alpha_pll_postdiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
{
diff --git a/drivers/clk/qcom/clk-alpha-pll.h b/drivers/clk/qcom/clk-alpha-pll.h
index 90ce201..f78bf4c 100644
--- a/drivers/clk/qcom/clk-alpha-pll.h
+++ b/drivers/clk/qcom/clk-alpha-pll.h
@@ -52,6 +52,7 @@ struct clk_alpha_pll_postdiv {
};

extern const struct clk_ops clk_alpha_pll_ops;
+extern const struct clk_ops clk_alpha_pll_hwfsm_ops;
extern const struct clk_ops clk_alpha_pll_postdiv_ops;

#endif
--
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