2020-03-18 03:35:21

by Anson Huang

Subject: [PATCH] clk: imx: clk-pllv3: Use readl_poll_timeout() for PLL lock wait

Use readl_poll_timeout() for PLL lock wait which can simplify the
code a lot.

Signed-off-by: Anson Huang <[email protected]>
---
drivers/clk/imx/clk-pllv3.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/imx/clk-pllv3.c b/drivers/clk/imx/clk-pllv3.c
index df91a82..3dfa9c3 100644
--- a/drivers/clk/imx/clk-pllv3.c
+++ b/drivers/clk/imx/clk-pllv3.c
@@ -7,6 +7,7 @@
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/err.h>
@@ -25,6 +26,8 @@
#define IMX7_ENET_PLL_POWER (0x1 << 5)
#define IMX7_DDR_PLL_POWER (0x1 << 20)

+#define PLL_LOCK_TIMEOUT 10000
+
/**
* struct clk_pllv3 - IMX PLL clock version 3
* @clk_hw: clock source
@@ -53,23 +56,14 @@ struct clk_pllv3 {

static int clk_pllv3_wait_lock(struct clk_pllv3 *pll)
{
- unsigned long timeout = jiffies + msecs_to_jiffies(10);
u32 val = readl_relaxed(pll->base) & pll->power_bit;

/* No need to wait for lock when pll is not powered up */
if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
return 0;

- /* Wait for PLL to lock */
- do {
- if (readl_relaxed(pll->base) & BM_PLL_LOCK)
- break;
- if (time_after(jiffies, timeout))
- break;
- usleep_range(50, 500);
- } while (1);
-
- return readl_relaxed(pll->base) & BM_PLL_LOCK ? 0 : -ETIMEDOUT;
+ return readl_poll_timeout(pll->base, val, val & BM_PLL_LOCK, 500,
+ PLL_LOCK_TIMEOUT);
}

static int clk_pllv3_prepare(struct clk_hw *hw)
--
2.7.4

2020-03-18 11:14:46

by Abel Vesa

Subject: Re: [PATCH] clk: imx: clk-pllv3: Use readl_poll_timeout() for PLL lock wait

On 20-03-18 11:26:44, Anson Huang wrote:
> Use readl_poll_timeout() for PLL lock wait which can simplify the
> code a lot.
>
> Signed-off-by: Anson Huang <[email protected]>

Reviewed-by: Abel Vesa <[email protected]>

> ---
> drivers/clk/imx/clk-pllv3.c | 16 +++++-----------
> 1 file changed, 5 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/clk/imx/clk-pllv3.c b/drivers/clk/imx/clk-pllv3.c
> index df91a82..3dfa9c3 100644
> --- a/drivers/clk/imx/clk-pllv3.c
> +++ b/drivers/clk/imx/clk-pllv3.c
> @@ -7,6 +7,7 @@
> #include <linux/clk-provider.h>
> #include <linux/delay.h>
> #include <linux/io.h>
> +#include <linux/iopoll.h>
> #include <linux/slab.h>
> #include <linux/jiffies.h>
> #include <linux/err.h>
> @@ -25,6 +26,8 @@
> #define IMX7_ENET_PLL_POWER (0x1 << 5)
> #define IMX7_DDR_PLL_POWER (0x1 << 20)
>
> +#define PLL_LOCK_TIMEOUT 10000
> +
> /**
> * struct clk_pllv3 - IMX PLL clock version 3
> * @clk_hw: clock source
> @@ -53,23 +56,14 @@ struct clk_pllv3 {
>
> static int clk_pllv3_wait_lock(struct clk_pllv3 *pll)
> {
> - unsigned long timeout = jiffies + msecs_to_jiffies(10);
> u32 val = readl_relaxed(pll->base) & pll->power_bit;
>
> /* No need to wait for lock when pll is not powered up */
> if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
> return 0;
>
> - /* Wait for PLL to lock */
> - do {
> - if (readl_relaxed(pll->base) & BM_PLL_LOCK)
> - break;
> - if (time_after(jiffies, timeout))
> - break;
> - usleep_range(50, 500);
> - } while (1);
> -
> - return readl_relaxed(pll->base) & BM_PLL_LOCK ? 0 : -ETIMEDOUT;
> + return readl_poll_timeout(pll->base, val, val & BM_PLL_LOCK, 500,
> + PLL_LOCK_TIMEOUT);
> }
>
> static int clk_pllv3_prepare(struct clk_hw *hw)
> --
> 2.7.4
>

2020-03-19 19:59:25

by Stephen Boyd

Subject: Re: [PATCH] clk: imx: clk-pllv3: Use readl_poll_timeout() for PLL lock wait

Quoting Anson Huang (2020-03-17 20:26:44)
> diff --git a/drivers/clk/imx/clk-pllv3.c b/drivers/clk/imx/clk-pllv3.c
> index df91a82..3dfa9c3 100644
> --- a/drivers/clk/imx/clk-pllv3.c
> +++ b/drivers/clk/imx/clk-pllv3.c
> @@ -53,23 +56,14 @@ struct clk_pllv3 {
>
> static int clk_pllv3_wait_lock(struct clk_pllv3 *pll)
> {
> - unsigned long timeout = jiffies + msecs_to_jiffies(10);
> u32 val = readl_relaxed(pll->base) & pll->power_bit;
>
> /* No need to wait for lock when pll is not powered up */
> if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
> return 0;
>
> - /* Wait for PLL to lock */
> - do {
> - if (readl_relaxed(pll->base) & BM_PLL_LOCK)
> - break;
> - if (time_after(jiffies, timeout))
> - break;
> - usleep_range(50, 500);
> - } while (1);
> -
> - return readl_relaxed(pll->base) & BM_PLL_LOCK ? 0 : -ETIMEDOUT;
> + return readl_poll_timeout(pll->base, val, val & BM_PLL_LOCK, 500,

Did you want to use readl_relaxed_poll_timeout() to keep it the same as
before?