mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-27 14:43:58 +08:00
a7ed099ffc
There are no conflicting files between the three mach-spear* directories and plat-spear any more, so we can now move all file to a common mach-spear directory. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
79 lines
1.8 KiB
C
79 lines
1.8 KiB
C
/*
|
|
* arch/arm/plat-spear/pl080.c
|
|
*
|
|
* DMAC pl080 definitions for SPEAr platform
|
|
*
|
|
* Copyright (C) 2012 ST Microelectronics
|
|
* Viresh Kumar <viresh.linux@gmail.com>
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
|
|
#include <linux/amba/pl08x.h>
|
|
#include <linux/amba/bus.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/err.h>
|
|
#include <linux/io.h>
|
|
#include <linux/spinlock_types.h>
|
|
#include <mach/spear.h>
|
|
#include <mach/misc_regs.h>
|
|
|
|
static spinlock_t lock = __SPIN_LOCK_UNLOCKED(x);
|
|
|
|
struct {
|
|
unsigned char busy;
|
|
unsigned char val;
|
|
} signals[16] = {{0, 0}, };
|
|
|
|
int pl080_get_signal(const struct pl08x_channel_data *cd)
|
|
{
|
|
unsigned int signal = cd->min_signal, val;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&lock, flags);
|
|
|
|
/* Return if signal is already acquired by somebody else */
|
|
if (signals[signal].busy &&
|
|
(signals[signal].val != cd->muxval)) {
|
|
spin_unlock_irqrestore(&lock, flags);
|
|
return -EBUSY;
|
|
}
|
|
|
|
/* If acquiring for the first time, configure it */
|
|
if (!signals[signal].busy) {
|
|
val = readl(DMA_CHN_CFG);
|
|
|
|
/*
|
|
* Each request line has two bits in DMA_CHN_CFG register. To
|
|
* goto the bits of current request line, do left shift of
|
|
* value by 2 * signal number.
|
|
*/
|
|
val &= ~(0x3 << (signal * 2));
|
|
val |= cd->muxval << (signal * 2);
|
|
writel(val, DMA_CHN_CFG);
|
|
}
|
|
|
|
signals[signal].busy++;
|
|
signals[signal].val = cd->muxval;
|
|
spin_unlock_irqrestore(&lock, flags);
|
|
|
|
return signal;
|
|
}
|
|
|
|
void pl080_put_signal(const struct pl08x_channel_data *cd, int signal)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&lock, flags);
|
|
|
|
/* if signal is not used */
|
|
if (!signals[signal].busy)
|
|
BUG();
|
|
|
|
signals[signal].busy--;
|
|
|
|
spin_unlock_irqrestore(&lock, flags);
|
|
}
|