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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/arm/mach-spear/pl080.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/arm/mach-spear/pl080.c')
-rw-r--r--kernel/arch/arm/mach-spear/pl080.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-spear/pl080.c b/kernel/arch/arm/mach-spear/pl080.c
new file mode 100644
index 000000000..cfa1199d0
--- /dev/null
+++ b/kernel/arch/arm/mach-spear/pl080.c
@@ -0,0 +1,78 @@
+/*
+ * 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);
+}