2015-12-01 11:14:59

by Maxime Ripard

Subject: [PATCH v2] clk: sunxi: pll2: Fix clock running too fast

Contrary to what the datasheet says, the pre divider doesn't seem to be
incremented by one in the PLL2, but just uses the value from the register,
with 0 being a bypass.

This fixes the audio playing too fast.

Since we now have the same pre-divider flags, and the only difference with
the A10 is the post-divider offset, also remove the structure to just pass
the offset as an argument.

Signed-off-by: Maxime Ripard <[email protected]>
---
drivers/clk/sunxi/clk-a10-pll2.c | 23 +++++------------------
1 file changed, 5 insertions(+), 18 deletions(-)

diff --git a/drivers/clk/sunxi/clk-a10-pll2.c b/drivers/clk/sunxi/clk-a10-pll2.c
index 5484c31ec568..0ee1f363e4be 100644
--- a/drivers/clk/sunxi/clk-a10-pll2.c
+++ b/drivers/clk/sunxi/clk-a10-pll2.c
@@ -41,15 +41,10 @@

#define SUN4I_PLL2_OUTPUTS 4

-struct sun4i_pll2_data {
- u32 post_div_offset;
- u32 pre_div_flags;
-};
-
static DEFINE_SPINLOCK(sun4i_a10_pll2_lock);

static void __init sun4i_pll2_setup(struct device_node *node,
- struct sun4i_pll2_data *data)
+ int post_div_offset)
{
const char *clk_name = node->name, *parent;
struct clk **clks, *base_clk, *prediv_clk;
@@ -76,7 +71,7 @@ static void __init sun4i_pll2_setup(struct device_node *node,
parent, 0, reg,
SUN4I_PLL2_PRE_DIV_SHIFT,
SUN4I_PLL2_PRE_DIV_WIDTH,
- data->pre_div_flags,
+ CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
&sun4i_a10_pll2_lock);
if (!prediv_clk) {
pr_err("Couldn't register the prediv clock\n");
@@ -127,7 +122,7 @@ static void __init sun4i_pll2_setup(struct device_node *node,
*/
val = readl(reg);
val &= ~(SUN4I_PLL2_POST_DIV_MASK << SUN4I_PLL2_POST_DIV_SHIFT);
- val |= (SUN4I_PLL2_POST_DIV_VALUE - data->post_div_offset) << SUN4I_PLL2_POST_DIV_SHIFT;
+ val |= (SUN4I_PLL2_POST_DIV_VALUE - post_div_offset) << SUN4I_PLL2_POST_DIV_SHIFT;
writel(val, reg);

of_property_read_string_index(node, "clock-output-names",
@@ -191,25 +186,17 @@ err_unmap:
iounmap(reg);
}

-static struct sun4i_pll2_data sun4i_a10_pll2_data = {
- .pre_div_flags = CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
-};
-
static void __init sun4i_a10_pll2_setup(struct device_node *node)
{
- sun4i_pll2_setup(node, &sun4i_a10_pll2_data);
+ sun4i_pll2_setup(node, 0);
}

CLK_OF_DECLARE(sun4i_a10_pll2, "allwinner,sun4i-a10-pll2-clk",
sun4i_a10_pll2_setup);

-static struct sun4i_pll2_data sun5i_a13_pll2_data = {
- .post_div_offset = 1,
-};
-
static void __init sun5i_a13_pll2_setup(struct device_node *node)
{
- sun4i_pll2_setup(node, &sun5i_a13_pll2_data);
+ sun4i_pll2_setup(node, 1);
}

CLK_OF_DECLARE(sun5i_a13_pll2, "allwinner,sun5i-a13-pll2-clk",
--
2.6.3

2015-12-03 07:31:27

by Stephen Boyd

Subject: Re: [PATCH v2] clk: sunxi: pll2: Fix clock running too fast

On 12/01, Maxime Ripard wrote:
> Contrary to what the datasheet says, the pre divider doesn't seem to be
> incremented by one in the PLL2, but just uses the value from the register,
> with 0 being a bypass.
>
> This fixes the audio playing too fast.
>
> Since we now have the same pre-divider flags, and the only difference with
> the A10 is the post-divider offset, also remove the structure to just pass
> the offset as an argument.
>
> Signed-off-by: Maxime Ripard <[email protected]>
> ---

Applied to clk-fixes + I added the Fixes tag.

--
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