lkml.org 
[lkml]   [2020]   [Sep]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/5] clk: ingenic: Use readl_poll_timeout instead of custom loop
Date
Use the readl_poll_timeout() function instead of rolling our own
busy-wait loops. This makes the code simpler.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---
drivers/clk/ingenic/cgu.c | 55 +++++++++++++++++++++------------------
1 file changed, 29 insertions(+), 26 deletions(-)

diff --git a/drivers/clk/ingenic/cgu.c b/drivers/clk/ingenic/cgu.c
index 12b14286734c..6bb5dedf0252 100644
--- a/drivers/clk/ingenic/cgu.c
+++ b/drivers/clk/ingenic/cgu.c
@@ -12,11 +12,14 @@
#include <linux/clkdev.h>
#include <linux/delay.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
#include <linux/math64.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
+#include <linux/time.h>
+
#include "cgu.h"

#define MHZ (1000 * 1000)
@@ -159,6 +162,16 @@ ingenic_pll_round_rate(struct clk_hw *hw, unsigned long req_rate,
return ingenic_pll_calc(clk_info, req_rate, *prate, NULL, NULL, NULL);
}

+static inline int ingenic_pll_check_stable(struct ingenic_cgu *cgu,
+ const struct ingenic_cgu_pll_info *pll_info)
+{
+ u32 ctl;
+
+ return readl_poll_timeout(cgu->base + pll_info->reg, ctl,
+ ctl & BIT(pll_info->stable_bit),
+ 0, 100 * USEC_PER_MSEC);
+}
+
static int
ingenic_pll_set_rate(struct clk_hw *hw, unsigned long req_rate,
unsigned long parent_rate)
@@ -201,9 +214,8 @@ static int ingenic_pll_enable(struct clk_hw *hw)
struct ingenic_cgu *cgu = ingenic_clk->cgu;
const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
- const unsigned int timeout = 100;
unsigned long flags;
- unsigned int i;
+ int ret;
u32 ctl;

spin_lock_irqsave(&cgu->lock, flags);
@@ -219,20 +231,10 @@ static int ingenic_pll_enable(struct clk_hw *hw)

writel(ctl, cgu->base + pll_info->reg);

- /* wait for the PLL to stabilise */
- for (i = 0; i < timeout; i++) {
- ctl = readl(cgu->base + pll_info->reg);
- if (ctl & BIT(pll_info->stable_bit))
- break;
- mdelay(1);
- }
-
+ ret = ingenic_pll_check_stable(cgu, pll_info);
spin_unlock_irqrestore(&cgu->lock, flags);

- if (i == timeout)
- return -EBUSY;
-
- return 0;
+ return ret;
}

static void ingenic_pll_disable(struct clk_hw *hw)
@@ -441,6 +443,16 @@ ingenic_clk_round_rate(struct clk_hw *hw, unsigned long req_rate,
return DIV_ROUND_UP(*parent_rate, div);
}

+static inline int ingenic_clk_check_stable(struct ingenic_cgu *cgu,
+ const struct ingenic_cgu_clk_info *clk_info)
+{
+ u32 reg;
+
+ return readl_poll_timeout(cgu->base + clk_info->div.reg, reg,
+ !(reg & BIT(clk_info->div.busy_bit)),
+ 0, 100 * USEC_PER_MSEC);
+}
+
static int
ingenic_clk_set_rate(struct clk_hw *hw, unsigned long req_rate,
unsigned long parent_rate)
@@ -448,9 +460,8 @@ ingenic_clk_set_rate(struct clk_hw *hw, unsigned long req_rate,
struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
struct ingenic_cgu *cgu = ingenic_clk->cgu;
- const unsigned timeout = 100;
unsigned long rate, flags;
- unsigned int hw_div, div, i;
+ unsigned int hw_div, div;
u32 reg, mask;
int ret = 0;

@@ -486,16 +497,8 @@ ingenic_clk_set_rate(struct clk_hw *hw, unsigned long req_rate,
writel(reg, cgu->base + clk_info->div.reg);

/* wait for the change to take effect */
- if (clk_info->div.busy_bit != -1) {
- for (i = 0; i < timeout; i++) {
- reg = readl(cgu->base + clk_info->div.reg);
- if (!(reg & BIT(clk_info->div.busy_bit)))
- break;
- mdelay(1);
- }
- if (i == timeout)
- ret = -EBUSY;
- }
+ if (clk_info->div.busy_bit != -1)
+ ret = ingenic_clk_check_stable(cgu, clk_info);

spin_unlock_irqrestore(&cgu->lock, flags);
return ret;
--
2.28.0
\
 
 \ /
  Last update: 2020-09-03 03:53    [W:0.159 / U:1.680 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site