2014-04-23 02:55:44

by Xiubo Li

Subject: [PATCHv2 1/2] clocksource: fix type confusion for clocksource_mmio_readX_Y

The types' definations are:
o cycle_t -> u64
o readl_relaxed -> u32
o readw_relaxed -> u16

So let clocksource_mmio_readX_Ys return a cast to cycle_t, though
this maybe look reduntant sometimes, it make sense and they will be
more readable and less confusion...

This patch clarifies the functions type and fix it.

Signed-off-by: Xiubo Li <[email protected]>
Cc: Daniel Lezcano <[email protected]>
---
drivers/clocksource/mmio.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c
index c0e2512..19a6b3f 100644
--- a/drivers/clocksource/mmio.c
+++ b/drivers/clocksource/mmio.c
@@ -22,22 +22,22 @@ static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c)

cycle_t clocksource_mmio_readl_up(struct clocksource *c)
{
- return readl_relaxed(to_mmio_clksrc(c)->reg);
+ return (cycle_t)readl_relaxed(to_mmio_clksrc(c)->reg);
}

cycle_t clocksource_mmio_readl_down(struct clocksource *c)
{
- return ~readl_relaxed(to_mmio_clksrc(c)->reg);
+ return ~(cycle_t)readl_relaxed(to_mmio_clksrc(c)->reg);
}

cycle_t clocksource_mmio_readw_up(struct clocksource *c)
{
- return readw_relaxed(to_mmio_clksrc(c)->reg);
+ return (cycle_t)readw_relaxed(to_mmio_clksrc(c)->reg);
}

cycle_t clocksource_mmio_readw_down(struct clocksource *c)
{
- return ~(unsigned)readw_relaxed(to_mmio_clksrc(c)->reg);
+ return ~(cycle_t)readw_relaxed(to_mmio_clksrc(c)->reg);
}

/**
--
1.8.4

2014-04-23 02:55:59

by Xiubo Li

Subject: [PATCHv2 2/2] clocksource: fix clocksource_mmio_readX_down

For some clocksource devices, for example, the registers are 32-bit, while
the lower 16-bit is used for timer counting(And reading the upper 16-bit
will return 0).

For example, when the counter value is 0x00001111, and then the
~readl_relaxed(to_mmio_clksrc(c)->reg) will return the value of 0xFFFFEEEE,
but it should be 0x0000EEEE.

So just using the c->mask to mask the unused bits.

Signed-off-by: Xiubo Li <[email protected]>
---
drivers/clocksource/mmio.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c
index 19a6b3f..1593ade 100644
--- a/drivers/clocksource/mmio.c
+++ b/drivers/clocksource/mmio.c
@@ -27,7 +27,7 @@ cycle_t clocksource_mmio_readl_up(struct clocksource *c)

cycle_t clocksource_mmio_readl_down(struct clocksource *c)
{
- return ~(cycle_t)readl_relaxed(to_mmio_clksrc(c)->reg);
+ return ~(cycle_t)readl_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
}

cycle_t clocksource_mmio_readw_up(struct clocksource *c)
@@ -37,7 +37,7 @@ cycle_t clocksource_mmio_readw_up(struct clocksource *c)

cycle_t clocksource_mmio_readw_down(struct clocksource *c)
{
- return ~(cycle_t)readw_relaxed(to_mmio_clksrc(c)->reg);
+ return ~(cycle_t)readw_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
}

/**
--
1.8.4