[PATCH v2 6/6] dma/imx-sdma: convernt to use bit ops
Richard Zhao
richard.zhao at linaro.org
Thu Jan 12 22:10:01 EST 2012
We don't need extra lock, so we use non-atomic bit ops to set/clear bits,
merge event_mask0 and event_mask1 into an array, it helps use bit ops.
It also fixs the issue:
sdmac->event_mask0 = 1 << sdmac->event_id0;
sdmac->event_mask1 = 1 << (sdmac->event_id0 - 32);
It event_id0 < 32, it shifts negative number. If event_id0 >= 32, it
shifts number >= sizeof(int). Both the cases behavior is undefined.
Signed-off-by: Richard Zhao <richard.zhao at linaro.org>
---
drivers/dma/imx-sdma.c | 68 ++++++++++++++++++++++++------------------------
1 files changed, 34 insertions(+), 34 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 22fd561..984c0f7 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -20,6 +20,7 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
+#include <linux/bitops.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
@@ -260,8 +261,8 @@ struct sdma_channel {
unsigned int pc_from_device, pc_to_device;
unsigned long flags;
dma_addr_t per_address;
- u32 event_mask0, event_mask1;
- u32 watermark_level;
+ unsigned long event_mask[2];
+ unsigned long watermark_level;
u32 shp_addr, per_addr;
struct dma_chan chan;
spinlock_t lock;
@@ -272,7 +273,7 @@ struct sdma_channel {
unsigned int chn_real_count;
};
-#define IMX_DMA_SG_LOOP (1 << 0)
+#define IMX_DMA_SG_LOOP BIT(0)
#define MAX_DMA_CHANNELS 32
#define MXC_SDMA_DEFAULT_PRIORITY 1
@@ -346,9 +347,9 @@ static const struct of_device_id sdma_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, sdma_dt_ids);
-#define SDMA_H_CONFIG_DSPDMA (1 << 12) /* indicates if the DSPDMA is used */
-#define SDMA_H_CONFIG_RTD_PINS (1 << 11) /* indicates if Real-Time Debug pins are enabled */
-#define SDMA_H_CONFIG_ACR (1 << 4) /* indicates if AHB freq /core freq = 2 or 1 */
+#define SDMA_H_CONFIG_DSPDMA BIT(12) /* indicates if the DSPDMA is used */
+#define SDMA_H_CONFIG_RTD_PINS BIT(11) /* indicates if Real-Time Debug pins are enabled */
+#define SDMA_H_CONFIG_ACR BIT(4) /* indicates if AHB freq /core freq = 2 or 1 */
#define SDMA_H_CONFIG_CSM (3) /* indicates which context switch mode is selected*/
static inline u32 chnenbl_ofs(struct sdma_engine *sdma, unsigned int event)
@@ -363,7 +364,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
{
struct sdma_engine *sdma = sdmac->sdma;
int channel = sdmac->channel;
- u32 evt, mcu, dsp;
+ unsigned long evt, mcu, dsp;
if (event_override && mcu_override && dsp_override)
return -EINVAL;
@@ -373,19 +374,19 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
dsp = readl_relaxed(sdma->regs + SDMA_H_DSPOVR);
if (dsp_override)
- dsp &= ~(1 << channel);
+ __clear_bit(channel, &dsp);
else
- dsp |= (1 << channel);
+ __set_bit(channel, &dsp);
if (event_override)
- evt &= ~(1 << channel);
+ __clear_bit(channel, &evt);
else
- evt |= (1 << channel);
+ __set_bit(channel, &evt);
if (mcu_override)
- mcu &= ~(1 << channel);
+ __clear_bit(channel, &mcu);
else
- mcu |= (1 << channel);
+ __set_bit(channel, &mcu);
writel_relaxed(evt, sdma->regs + SDMA_H_EVTOVR);
writel_relaxed(mcu, sdma->regs + SDMA_H_HOSTOVR);
@@ -396,7 +397,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
{
- writel(1 << channel, sdma->regs + SDMA_H_START);
+ writel(BIT(channel), sdma->regs + SDMA_H_START);
}
/*
@@ -457,11 +458,11 @@ static void sdma_event_enable(struct sdma_channel *sdmac, unsigned int event)
{
struct sdma_engine *sdma = sdmac->sdma;
int channel = sdmac->channel;
- u32 val;
+ unsigned long val;
u32 chnenbl = chnenbl_ofs(sdma, event);
val = readl_relaxed(sdma->regs + chnenbl);
- val |= (1 << channel);
+ __set_bit(channel, &val);
writel_relaxed(val, sdma->regs + chnenbl);
}
@@ -470,10 +471,10 @@ static void sdma_event_disable(struct sdma_channel *sdmac, unsigned int event)
struct sdma_engine *sdma = sdmac->sdma;
int channel = sdmac->channel;
u32 chnenbl = chnenbl_ofs(sdma, event);
- u32 val;
+ unsigned long val;
val = readl_relaxed(sdma->regs + chnenbl);
- val &= ~(1 << channel);
+ __clear_bit(channel, &val);
writel_relaxed(val, sdma->regs + chnenbl);
}
@@ -550,7 +551,7 @@ static void mxc_sdma_handle_channel(struct sdma_channel *sdmac)
static irqreturn_t sdma_int_handler(int irq, void *dev_id)
{
struct sdma_engine *sdma = dev_id;
- u32 stat;
+ unsigned long stat;
stat = readl_relaxed(sdma->regs + SDMA_H_INTR);
writel_relaxed(stat, sdma->regs + SDMA_H_INTR);
@@ -561,7 +562,7 @@ static irqreturn_t sdma_int_handler(int irq, void *dev_id)
mxc_sdma_handle_channel(sdmac);
- stat &= ~(1 << channel);
+ __clear_bit(channel, &stat);
}
return IRQ_HANDLED;
@@ -669,11 +670,11 @@ static int sdma_load_context(struct sdma_channel *sdmac)
return load_address;
dev_dbg(sdma->dev, "load_address = %d\n", load_address);
- dev_dbg(sdma->dev, "wml = 0x%08x\n", sdmac->watermark_level);
+ dev_dbg(sdma->dev, "wml = 0x%08x\n", (u32)sdmac->watermark_level);
dev_dbg(sdma->dev, "shp_addr = 0x%08x\n", sdmac->shp_addr);
dev_dbg(sdma->dev, "per_addr = 0x%08x\n", sdmac->per_addr);
- dev_dbg(sdma->dev, "event_mask0 = 0x%08x\n", sdmac->event_mask0);
- dev_dbg(sdma->dev, "event_mask1 = 0x%08x\n", sdmac->event_mask1);
+ dev_dbg(sdma->dev, "event_mask0 = 0x%08x\n", (u32)sdmac->event_mask[0]);
+ dev_dbg(sdma->dev, "event_mask1 = 0x%08x\n", (u32)sdmac->event_mask[1]);
mutex_lock(&sdma->channel_0_lock);
@@ -683,8 +684,8 @@ static int sdma_load_context(struct sdma_channel *sdmac)
/* Send by context the event mask,base address for peripheral
* and watermark level
*/
- context->gReg[0] = sdmac->event_mask1;
- context->gReg[1] = sdmac->event_mask0;
+ context->gReg[0] = sdmac->event_mask[1];
+ context->gReg[1] = sdmac->event_mask[0];
context->gReg[2] = sdmac->per_addr;
context->gReg[6] = sdmac->shp_addr;
context->gReg[7] = sdmac->watermark_level;
@@ -707,7 +708,7 @@ static void sdma_disable_channel(struct sdma_channel *sdmac)
struct sdma_engine *sdma = sdmac->sdma;
int channel = sdmac->channel;
- writel_relaxed(1 << channel, sdma->regs + SDMA_H_STATSTOP);
+ writel_relaxed(BIT(channel), sdma->regs + SDMA_H_STATSTOP);
sdmac->status = DMA_ERROR;
}
@@ -717,8 +718,8 @@ static int sdma_config_channel(struct sdma_channel *sdmac)
sdma_disable_channel(sdmac);
- sdmac->event_mask0 = 0;
- sdmac->event_mask1 = 0;
+ sdmac->event_mask[0] = 0;
+ sdmac->event_mask[1] = 0;
sdmac->shp_addr = 0;
sdmac->per_addr = 0;
@@ -746,15 +747,14 @@ static int sdma_config_channel(struct sdma_channel *sdmac)
(sdmac->peripheral_type != IMX_DMATYPE_DSP)) {
/* Handle multiple event channels differently */
if (sdmac->event_id1) {
- sdmac->event_mask1 = 1 << (sdmac->event_id1 % 32);
+ sdmac->event_mask[1] = BIT(sdmac->event_id1 % 32);
if (sdmac->event_id1 > 31)
- sdmac->watermark_level |= 1 << 31;
- sdmac->event_mask0 = 1 << (sdmac->event_id0 % 32);
+ __set_bit(31, &sdmac->watermark_level);
+ sdmac->event_mask[0] = BIT(sdmac->event_id0 % 32);
if (sdmac->event_id0 > 31)
- sdmac->watermark_level |= 1 << 30;
+ __set_bit(30, &sdmac->watermark_level);
} else {
- sdmac->event_mask0 = 1 << sdmac->event_id0;
- sdmac->event_mask1 = 1 << (sdmac->event_id0 - 32);
+ __set_bit(sdmac->event_id0, sdmac->event_mask);
}
/* Watermark Level */
sdmac->watermark_level |= sdmac->watermark_level;
--
1.7.5.4
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