[PATCH 4/6] ARM: add big endian support for peripheral access
Junxiao Bi
junxiao.bi at windriver.com
Mon Nov 14 21:06:23 EST 2011
From: Xue Ying <ying.xue at windriver.com>
Since data from arm peripheral are little-endian and __raw_read*/__raw_write*
don't do any endian conversion, we should use read*/write*_relaxed to replace
them as the _relaxed version only adds endian conversion based on __raw version
which isn't like read*/write* that adds IO barriers which will affect performance.
Signed-off-by: Xue Ying <ying.xue at windriver.com>
Signed-off-by: Junxiao Bi <junxiao.bi at windriver.com>
---
arch/arm/kernel/smp_scu.c | 10 +++++-----
arch/arm/kernel/smp_twd.c | 20 ++++++++++----------
include/linux/mtd/map.h | 16 ++++++++--------
3 files changed, 23 insertions(+), 23 deletions(-)
diff --git a/arch/arm/kernel/smp_scu.c b/arch/arm/kernel/smp_scu.c
index 8f5dd79..0324435 100644
--- a/arch/arm/kernel/smp_scu.c
+++ b/arch/arm/kernel/smp_scu.c
@@ -27,7 +27,7 @@
*/
unsigned int __init scu_get_core_count(void __iomem *scu_base)
{
- unsigned int ncores = __raw_readl(scu_base + SCU_CONFIG);
+ unsigned int ncores = readl_relaxed(scu_base + SCU_CONFIG);
return (ncores & 0x03) + 1;
}
@@ -41,19 +41,19 @@ void scu_enable(void __iomem *scu_base)
#ifdef CONFIG_ARM_ERRATA_764369
/* Cortex-A9 only */
if ((read_cpuid(CPUID_ID) & 0xff0ffff0) == 0x410fc090) {
- scu_ctrl = __raw_readl(scu_base + 0x30);
+ scu_ctrl = readl_relaxed(scu_base + 0x30);
if (!(scu_ctrl & 1))
- __raw_writel(scu_ctrl | 0x1, scu_base + 0x30);
+ writel_relaxed(scu_ctrl | 0x1, scu_base + 0x30);
}
#endif
- scu_ctrl = __raw_readl(scu_base + SCU_CTRL);
+ scu_ctrl = readl_relaxed(scu_base + SCU_CTRL);
/* already enabled? */
if (scu_ctrl & 1)
return;
scu_ctrl |= 1;
- __raw_writel(scu_ctrl, scu_base + SCU_CTRL);
+ writel_relaxed(scu_ctrl, scu_base + SCU_CTRL);
/*
* Ensure that the data accessed by CPU0 before the SCU was
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index a8a6682..0864d92 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -39,7 +39,7 @@ static void twd_set_mode(enum clock_event_mode mode,
/* timer load already set up */
ctrl = TWD_TIMER_CONTROL_ENABLE | TWD_TIMER_CONTROL_IT_ENABLE
| TWD_TIMER_CONTROL_PERIODIC;
- __raw_writel(twd_timer_rate / HZ, twd_base + TWD_TIMER_LOAD);
+ writel_relaxed(twd_timer_rate / HZ, twd_base + TWD_TIMER_LOAD);
break;
case CLOCK_EVT_MODE_ONESHOT:
/* period set, and timer enabled in 'next_event' hook */
@@ -51,18 +51,18 @@ static void twd_set_mode(enum clock_event_mode mode,
ctrl = 0;
}
- __raw_writel(ctrl, twd_base + TWD_TIMER_CONTROL);
+ writel_relaxed(ctrl, twd_base + TWD_TIMER_CONTROL);
}
static int twd_set_next_event(unsigned long evt,
struct clock_event_device *unused)
{
- unsigned long ctrl = __raw_readl(twd_base + TWD_TIMER_CONTROL);
+ unsigned long ctrl = readl_relaxed(twd_base + TWD_TIMER_CONTROL);
ctrl |= TWD_TIMER_CONTROL_ENABLE;
- __raw_writel(evt, twd_base + TWD_TIMER_COUNTER);
- __raw_writel(ctrl, twd_base + TWD_TIMER_CONTROL);
+ writel_relaxed(evt, twd_base + TWD_TIMER_COUNTER);
+ writel_relaxed(ctrl, twd_base + TWD_TIMER_CONTROL);
return 0;
}
@@ -75,8 +75,8 @@ static int twd_set_next_event(unsigned long evt,
*/
int twd_timer_ack(void)
{
- if (__raw_readl(twd_base + TWD_TIMER_INTSTAT)) {
- __raw_writel(1, twd_base + TWD_TIMER_INTSTAT);
+ if (readl_relaxed(twd_base + TWD_TIMER_INTSTAT)) {
+ writel_relaxed(1, twd_base + TWD_TIMER_INTSTAT);
return 1;
}
@@ -111,15 +111,15 @@ static void __cpuinit twd_calibrate_rate(void)
waitjiffies += 5;
/* enable, no interrupt or reload */
- __raw_writel(0x1, twd_base + TWD_TIMER_CONTROL);
+ writel_relaxed(0x1, twd_base + TWD_TIMER_CONTROL);
/* maximum value */
- __raw_writel(0xFFFFFFFFU, twd_base + TWD_TIMER_COUNTER);
+ writel_relaxed(0xFFFFFFFFU, twd_base + TWD_TIMER_COUNTER);
while (get_jiffies_64() < waitjiffies)
udelay(10);
- count = __raw_readl(twd_base + TWD_TIMER_COUNTER);
+ count = readl_relaxed(twd_base + TWD_TIMER_COUNTER);
twd_timer_rate = (0xFFFFFFFFU - count) * (HZ / 5);
diff --git a/include/linux/mtd/map.h b/include/linux/mtd/map.h
index a9e6ba4..74b266d 100644
--- a/include/linux/mtd/map.h
+++ b/include/linux/mtd/map.h
@@ -393,14 +393,14 @@ static inline map_word inline_map_read(struct map_info *map, unsigned long ofs)
map_word r;
if (map_bankwidth_is_1(map))
- r.x[0] = __raw_readb(map->virt + ofs);
+ r.x[0] = readb_relaxed(map->virt + ofs);
else if (map_bankwidth_is_2(map))
- r.x[0] = __raw_readw(map->virt + ofs);
+ r.x[0] = readw_relaxed(map->virt + ofs);
else if (map_bankwidth_is_4(map))
- r.x[0] = __raw_readl(map->virt + ofs);
+ r.x[0] = readl_relaxed(map->virt + ofs);
#if BITS_PER_LONG >= 64
else if (map_bankwidth_is_8(map))
- r.x[0] = __raw_readq(map->virt + ofs);
+ r.x[0] = readq_relaxed(map->virt + ofs);
#endif
else if (map_bankwidth_is_large(map))
memcpy_fromio(r.x, map->virt+ofs, map->bankwidth);
@@ -413,14 +413,14 @@ static inline map_word inline_map_read(struct map_info *map, unsigned long ofs)
static inline void inline_map_write(struct map_info *map, const map_word datum, unsigned long ofs)
{
if (map_bankwidth_is_1(map))
- __raw_writeb(datum.x[0], map->virt + ofs);
+ writeb_relaxed(datum.x[0], map->virt + ofs);
else if (map_bankwidth_is_2(map))
- __raw_writew(datum.x[0], map->virt + ofs);
+ writew_relaxed(datum.x[0], map->virt + ofs);
else if (map_bankwidth_is_4(map))
- __raw_writel(datum.x[0], map->virt + ofs);
+ writel_relaxed(datum.x[0], map->virt + ofs);
#if BITS_PER_LONG >= 64
else if (map_bankwidth_is_8(map))
- __raw_writeq(datum.x[0], map->virt + ofs);
+ writeq_relaxed(datum.x[0], map->virt + ofs);
#endif
else if (map_bankwidth_is_large(map))
memcpy_toio(map->virt+ofs, datum.x, map->bankwidth);
--
1.7.0.4
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