[PATCH] clk: imx: gate2: Fix the is_enabled op

From: Abel Vesa
Date: Mon Oct 26 2020 - 14:51:13 EST


The clock is considered to be enabled only if the controlling bits
match the cgr_val mask. Also make sure the is_enabled returns the
correct vaule by locking the access to the register.

Signed-off-by: Abel Vesa <abel.vesa@xxxxxxx>
Fixes: 1e54afe9fcfe ("clk: imx: gate2: Allow single bit gating clock")
---
drivers/clk/imx/clk-gate2.c | 60 ++++++++++++++++++++-------------------------
drivers/clk/imx/clk.h | 8 ++----
2 files changed, 29 insertions(+), 39 deletions(-)

diff --git a/drivers/clk/imx/clk-gate2.c b/drivers/clk/imx/clk-gate2.c
index 7eed708..f320bd2b 100644
--- a/drivers/clk/imx/clk-gate2.c
+++ b/drivers/clk/imx/clk-gate2.c
@@ -37,10 +37,22 @@ struct clk_gate2 {

#define to_clk_gate2(_hw) container_of(_hw, struct clk_gate2, hw)

+static void clk_gate2_do_shared_clks(struct clk_hw *hw, bool enable)
+{
+ struct clk_gate2 *gate = to_clk_gate2(hw);
+ u32 reg;
+
+ reg = readl(gate->reg);
+ if (enable)
+ reg |= gate->cgr_val << gate->bit_idx;
+ else
+ reg &= ~(gate->cgr_val << gate->bit_idx);
+ writel(reg, gate->reg);
+}
+
static int clk_gate2_enable(struct clk_hw *hw)
{
struct clk_gate2 *gate = to_clk_gate2(hw);
- u32 reg;
unsigned long flags;
int ret = 0;

@@ -49,15 +61,7 @@ static int clk_gate2_enable(struct clk_hw *hw)
if (gate->share_count && (*gate->share_count)++ > 0)
goto out;

- if (gate->flags & IMX_CLK_GATE2_SINGLE_BIT) {
- ret = clk_gate_ops.enable(hw);
- } else {
- reg = readl(gate->reg);
- reg &= ~(3 << gate->bit_idx);
- reg |= gate->cgr_val << gate->bit_idx;
- writel(reg, gate->reg);
- }
-
+ clk_gate2_do_shared_clks(hw, true);
out:
spin_unlock_irqrestore(gate->lock, flags);

@@ -67,7 +71,6 @@ static int clk_gate2_enable(struct clk_hw *hw)
static void clk_gate2_disable(struct clk_hw *hw)
{
struct clk_gate2 *gate = to_clk_gate2(hw);
- u32 reg;
unsigned long flags;

spin_lock_irqsave(gate->lock, flags);
@@ -79,23 +82,16 @@ static void clk_gate2_disable(struct clk_hw *hw)
goto out;
}

- if (gate->flags & IMX_CLK_GATE2_SINGLE_BIT) {
- clk_gate_ops.disable(hw);
- } else {
- reg = readl(gate->reg);
- reg &= ~(3 << gate->bit_idx);
- writel(reg, gate->reg);
- }
-
+ clk_gate2_do_shared_clks(hw, false);
out:
spin_unlock_irqrestore(gate->lock, flags);
}

-static int clk_gate2_reg_is_enabled(void __iomem *reg, u8 bit_idx)
+static int clk_gate2_reg_is_enabled(void __iomem *reg, u8 bit_idx, u8 cgr_val)
{
u32 val = readl(reg);

- if (((val >> bit_idx) & 1) == 1)
+ if (((val >> bit_idx) & cgr_val) == cgr_val)
return 1;

return 0;
@@ -104,29 +100,27 @@ static int clk_gate2_reg_is_enabled(void __iomem *reg, u8 bit_idx)
static int clk_gate2_is_enabled(struct clk_hw *hw)
{
struct clk_gate2 *gate = to_clk_gate2(hw);
+ unsigned long flags;
+ int ret;

- if (gate->flags & IMX_CLK_GATE2_SINGLE_BIT)
- return clk_gate_ops.is_enabled(hw);
+ spin_lock_irqsave(gate->lock, flags);

- return clk_gate2_reg_is_enabled(gate->reg, gate->bit_idx);
+ ret = clk_gate2_reg_is_enabled(gate->reg, gate->bit_idx, gate->cgr_val);
+
+ spin_unlock_irqrestore(gate->lock, flags);
+
+ return ret;
}

static void clk_gate2_disable_unused(struct clk_hw *hw)
{
struct clk_gate2 *gate = to_clk_gate2(hw);
unsigned long flags;
- u32 reg;
-
- if (gate->flags & IMX_CLK_GATE2_SINGLE_BIT)
- return;

spin_lock_irqsave(gate->lock, flags);

- if (!gate->share_count || *gate->share_count == 0) {
- reg = readl(gate->reg);
- reg &= ~(3 << gate->bit_idx);
- writel(reg, gate->reg);
- }
+ if (!gate->share_count || *gate->share_count == 0)
+ clk_gate2_do_shared_clks(hw, false);

spin_unlock_irqrestore(gate->lock, flags);
}
diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
index 3b796b3..069b07d 100644
--- a/drivers/clk/imx/clk.h
+++ b/drivers/clk/imx/clk.h
@@ -6,8 +6,6 @@
#include <linux/spinlock.h>
#include <linux/clk-provider.h>

-#define IMX_CLK_GATE2_SINGLE_BIT 1
-
extern spinlock_t imx_ccm_lock;

void imx_check_clocks(struct clk *clks[], unsigned int count);
@@ -383,10 +381,8 @@ static inline struct clk_hw *imx_dev_clk_hw_gate_shared(struct device *dev,
void __iomem *reg, u8 shift,
unsigned int *share_count)
{
- return clk_hw_register_gate2(NULL, name, parent, CLK_SET_RATE_PARENT |
- CLK_OPS_PARENT_ENABLE, reg, shift, 0x3,
- IMX_CLK_GATE2_SINGLE_BIT,
- &imx_ccm_lock, share_count);
+ return clk_hw_register_gate2(dev, name, parent, CLK_SET_RATE_PARENT | CLK_OPS_PARENT_ENABLE, reg,
+ shift, 0x1, 0, &imx_ccm_lock, share_count);
}

static inline struct clk *imx_clk_gate2_cgr(const char *name,
--
2.7.4