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Message-Id: <1418570933-21585-1-git-send-email-stefan.wahren@i2se.com>
Date: Sun, 14 Dec 2014 15:28:53 +0000
From: Stefan Wahren <stefan.wahren@...e.com>
To: mturquette@...aro.org
Cc: festevam@...il.com, shawn.guo@...aro.org, marex@...x.de,
linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
Stefan Wahren <stefan.wahren@...e.com>
Subject: [PATCH RFC] clk: mxs: Fix invalid 32-bit access to frac registers
According to i.MX23 and i.MX28 reference manual the fractional
clock control registers must be addressed by byte instructions.
This patch fixes the erroneous 32-bit access to these registers.
The changes has been tested only with a i.MX28 board, because i don't
have access to an i.MX23 board.
Signed-off-by: Stefan Wahren <stefan.wahren@...e.com>
---
drivers/clk/mxs/clk-imx23.c | 8 +++++---
drivers/clk/mxs/clk-imx28.c | 14 ++++++++------
drivers/clk/mxs/clk-ref.c | 19 ++++++++++---------
3 files changed, 23 insertions(+), 18 deletions(-)
diff --git a/drivers/clk/mxs/clk-imx23.c b/drivers/clk/mxs/clk-imx23.c
index 9fc9359..371ba03 100644
--- a/drivers/clk/mxs/clk-imx23.c
+++ b/drivers/clk/mxs/clk-imx23.c
@@ -46,7 +46,8 @@ static void __iomem *digctrl;
#define BP_CLKSEQ_BYPASS_SAIF 0
#define BP_CLKSEQ_BYPASS_SSP 5
#define BP_SAIF_DIV_FRAC_EN 16
-#define BP_FRAC_IOFRAC 24
+
+#define FRAC_IO 3
static void __init clk_misc_init(void)
{
@@ -72,9 +73,10 @@ static void __init clk_misc_init(void)
/*
* 480 MHz seems too high to be ssp clock source directly,
* so set frac to get a 288 MHz ref_io.
+ * According to reference manual we must access frac bytewise.
*/
- writel_relaxed(0x3f << BP_FRAC_IOFRAC, FRAC + CLR);
- writel_relaxed(30 << BP_FRAC_IOFRAC, FRAC + SET);
+ writeb_relaxed(0x3f, FRAC + FRAC_IO + CLR);
+ writeb_relaxed(30, FRAC + FRAC_IO + SET);
}
static const char *sel_pll[] __initconst = { "pll", "ref_xtal", };
diff --git a/drivers/clk/mxs/clk-imx28.c b/drivers/clk/mxs/clk-imx28.c
index a6c3501..3eae119 100644
--- a/drivers/clk/mxs/clk-imx28.c
+++ b/drivers/clk/mxs/clk-imx28.c
@@ -53,8 +53,9 @@ static void __iomem *clkctrl;
#define BP_ENET_SLEEP 31
#define BP_CLKSEQ_BYPASS_SAIF0 0
#define BP_CLKSEQ_BYPASS_SSP0 3
-#define BP_FRAC0_IO1FRAC 16
-#define BP_FRAC0_IO0FRAC 24
+
+#define FRAC0_IO1 2
+#define FRAC0_IO0 3
static void __iomem *digctrl;
#define DIGCTRL digctrl
@@ -118,11 +119,12 @@ static void __init clk_misc_init(void)
/*
* 480 MHz seems too high to be ssp clock source directly,
* so set frac0 to get a 288 MHz ref_io0 and ref_io1.
+ * According to reference manual we must access frac0 bytewise.
*/
- val = readl_relaxed(FRAC0);
- val &= ~((0x3f << BP_FRAC0_IO0FRAC) | (0x3f << BP_FRAC0_IO1FRAC));
- val |= (30 << BP_FRAC0_IO0FRAC) | (30 << BP_FRAC0_IO1FRAC);
- writel_relaxed(val, FRAC0);
+ writeb_relaxed(0x3f, FRAC0 + FRAC0_IO0 + CLR);
+ writeb_relaxed(30, FRAC0 + FRAC0_IO0 + SET);
+ writeb_relaxed(0x3f, FRAC0 + FRAC0_IO1 + CLR);
+ writeb_relaxed(30, FRAC0 + FRAC0_IO1 + SET);
}
static const char *sel_cpu[] __initconst = { "ref_cpu", "ref_xtal", };
diff --git a/drivers/clk/mxs/clk-ref.c b/drivers/clk/mxs/clk-ref.c
index 4adeed6..ad3851c 100644
--- a/drivers/clk/mxs/clk-ref.c
+++ b/drivers/clk/mxs/clk-ref.c
@@ -16,6 +16,8 @@
#include <linux/slab.h>
#include "clk.h"
+#define BF_CLKGATE BIT(7)
+
/**
* struct clk_ref - mxs reference clock
* @hw: clk_hw for the reference clock
@@ -39,7 +41,7 @@ static int clk_ref_enable(struct clk_hw *hw)
{
struct clk_ref *ref = to_clk_ref(hw);
- writel_relaxed(1 << ((ref->idx + 1) * 8 - 1), ref->reg + CLR);
+ writeb_relaxed(BF_CLKGATE, ref->reg + ref->idx + CLR);
return 0;
}
@@ -48,7 +50,7 @@ static void clk_ref_disable(struct clk_hw *hw)
{
struct clk_ref *ref = to_clk_ref(hw);
- writel_relaxed(1 << ((ref->idx + 1) * 8 - 1), ref->reg + SET);
+ writeb_relaxed(BF_CLKGATE, ref->reg + ref->idx + SET);
}
static unsigned long clk_ref_recalc_rate(struct clk_hw *hw,
@@ -56,7 +58,7 @@ static unsigned long clk_ref_recalc_rate(struct clk_hw *hw,
{
struct clk_ref *ref = to_clk_ref(hw);
u64 tmp = parent_rate;
- u8 frac = (readl_relaxed(ref->reg) >> (ref->idx * 8)) & 0x3f;
+ u8 frac = readb_relaxed(ref->reg + ref->idx) & 0x3f;
tmp *= 18;
do_div(tmp, frac);
@@ -93,8 +95,7 @@ static int clk_ref_set_rate(struct clk_hw *hw, unsigned long rate,
struct clk_ref *ref = to_clk_ref(hw);
unsigned long flags;
u64 tmp = parent_rate;
- u32 val;
- u8 frac, shift = ref->idx * 8;
+ u8 frac, val;
tmp = tmp * 18 + rate / 2;
do_div(tmp, rate);
@@ -107,10 +108,10 @@ static int clk_ref_set_rate(struct clk_hw *hw, unsigned long rate,
spin_lock_irqsave(&mxs_lock, flags);
- val = readl_relaxed(ref->reg);
- val &= ~(0x3f << shift);
- val |= frac << shift;
- writel_relaxed(val, ref->reg);
+ val = readb_relaxed(ref->reg + ref->idx);
+ val &= ~0x3f;
+ val |= frac;
+ writeb_relaxed(val, ref->reg + ref->idx);
spin_unlock_irqrestore(&mxs_lock, flags);
--
1.7.9.5
--
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