gpu: ipu-v3: Add SMFC code

The Sensor Multi Fifo Controller (SMFC) is used as a buffer between
the two CSIs (writing simultaneously) and up to four IDMAC channels.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
diff --git a/drivers/gpu/ipu-v3/ipu-smfc.c b/drivers/gpu/ipu-v3/ipu-smfc.c
new file mode 100644
index 0000000..e4f85ad
--- /dev/null
+++ b/drivers/gpu/ipu-v3/ipu-smfc.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright 2008-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#define DEBUG
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <video/imx-ipu-v3.h>
+
+#include "ipu-prv.h"
+
+struct ipu_smfc_priv {
+	void __iomem *base;
+	spinlock_t lock;
+};
+
+/*SMFC Registers */
+#define SMFC_MAP	0x0000
+#define SMFC_WMC	0x0004
+#define SMFC_BS		0x0008
+
+int ipu_smfc_set_burstsize(struct ipu_soc *ipu, int channel, int burstsize)
+{
+	struct ipu_smfc_priv *smfc = ipu->smfc_priv;
+	unsigned long flags;
+	u32 val, shift;
+
+	spin_lock_irqsave(&smfc->lock, flags);
+
+	shift = channel * 4;
+	val = readl(smfc->base + SMFC_BS);
+	val &= ~(0xf << shift);
+	val |= burstsize << shift;
+	writel(val, smfc->base + SMFC_BS);
+
+	spin_unlock_irqrestore(&smfc->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipu_smfc_set_burstsize);
+
+int ipu_smfc_map_channel(struct ipu_soc *ipu, int channel, int csi_id, int mipi_id)
+{
+	struct ipu_smfc_priv *smfc = ipu->smfc_priv;
+	unsigned long flags;
+	u32 val, shift;
+
+	spin_lock_irqsave(&smfc->lock, flags);
+
+	shift = channel * 3;
+	val = readl(smfc->base + SMFC_MAP);
+	val &= ~(0x7 << shift);
+	val |= ((csi_id << 2) | mipi_id) << shift;
+	writel(val, smfc->base + SMFC_MAP);
+
+	spin_unlock_irqrestore(&smfc->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipu_smfc_map_channel);
+
+int ipu_smfc_init(struct ipu_soc *ipu, struct device *dev,
+		  unsigned long base)
+{
+	struct ipu_smfc_priv *smfc;
+
+	smfc = devm_kzalloc(dev, sizeof(*smfc), GFP_KERNEL);
+	if (!smfc)
+		return -ENOMEM;
+
+	ipu->smfc_priv = smfc;
+	spin_lock_init(&smfc->lock);
+
+	smfc->base = devm_ioremap(dev, base, PAGE_SIZE);
+	if (!smfc->base)
+		return -ENOMEM;
+
+	pr_debug("%s: ioremap 0x%08lx -> %p\n", __func__, base, smfc->base);
+
+	return 0;
+}
+
+void ipu_smfc_exit(struct ipu_soc *ipu)
+{
+}