ARM: OMAP: Add mailbox support for IVA

This patch adds a generic mailbox interface for for DSP and IVA
(Image Video Accelerator). This patch itself doesn't contain
any IVA driver.

Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-omap1/mailbox.c b/arch/arm/mach-omap1/mailbox.c
new file mode 100644
index 0000000..d3abf56
--- /dev/null
+++ b/arch/arm/mach-omap1/mailbox.c
@@ -0,0 +1,206 @@
+/*
+ * Mailbox reservation modules for DSP
+ *
+ * Copyright (C) 2006 Nokia Corporation
+ * Written by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/resource.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <asm/arch/mailbox.h>
+#include <asm/arch/irqs.h>
+#include <asm/io.h>
+
+#define MAILBOX_ARM2DSP1		0x00
+#define MAILBOX_ARM2DSP1b		0x04
+#define MAILBOX_DSP2ARM1		0x08
+#define MAILBOX_DSP2ARM1b		0x0c
+#define MAILBOX_DSP2ARM2		0x10
+#define MAILBOX_DSP2ARM2b		0x14
+#define MAILBOX_ARM2DSP1_Flag		0x18
+#define MAILBOX_DSP2ARM1_Flag		0x1c
+#define MAILBOX_DSP2ARM2_Flag		0x20
+
+unsigned long mbox_base;
+
+struct omap_mbox1_fifo {
+	unsigned long cmd;
+	unsigned long data;
+	unsigned long flag;
+};
+
+struct omap_mbox1_priv {
+	struct omap_mbox1_fifo tx_fifo;
+	struct omap_mbox1_fifo rx_fifo;
+};
+
+static inline int mbox_read_reg(unsigned int reg)
+{
+	return __raw_readw(mbox_base + reg);
+}
+
+static inline void mbox_write_reg(unsigned int val, unsigned int reg)
+{
+	__raw_writew(val, mbox_base + reg);
+}
+
+/* msg */
+static inline mbox_msg_t omap1_mbox_fifo_read(struct omap_mbox *mbox)
+{
+	struct omap_mbox1_fifo *fifo =
+		&((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
+	mbox_msg_t msg;
+
+	msg = mbox_read_reg(fifo->data);
+	msg |= ((mbox_msg_t) mbox_read_reg(fifo->cmd)) << 16;
+
+	return msg;
+}
+
+static inline void
+omap1_mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
+{
+	struct omap_mbox1_fifo *fifo =
+		&((struct omap_mbox1_priv *)mbox->priv)->tx_fifo;
+
+	mbox_write_reg(msg & 0xffff, fifo->data);
+	mbox_write_reg(msg >> 16, fifo->cmd);
+}
+
+static inline int omap1_mbox_fifo_empty(struct omap_mbox *mbox)
+{
+	return 0;
+}
+
+static inline int omap1_mbox_fifo_full(struct omap_mbox *mbox)
+{
+	struct omap_mbox1_fifo *fifo =
+		&((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
+
+	return (mbox_read_reg(fifo->flag));
+}
+
+/* irq */
+static inline void
+omap1_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
+{
+	if (irq == IRQ_RX)
+		enable_irq(mbox->irq);
+}
+
+static inline void
+omap1_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
+{
+	if (irq == IRQ_RX)
+		disable_irq(mbox->irq);
+}
+
+static inline int
+omap1_mbox_is_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
+{
+	if (irq == IRQ_TX)
+		return 0;
+	return 1;
+}
+
+static struct omap_mbox_ops omap1_mbox_ops = {
+	.type		= OMAP_MBOX_TYPE1,
+	.fifo_read	= omap1_mbox_fifo_read,
+	.fifo_write	= omap1_mbox_fifo_write,
+	.fifo_empty	= omap1_mbox_fifo_empty,
+	.fifo_full	= omap1_mbox_fifo_full,
+	.enable_irq	= omap1_mbox_enable_irq,
+	.disable_irq	= omap1_mbox_disable_irq,
+	.is_irq		= omap1_mbox_is_irq,
+};
+
+/* FIXME: the following struct should be created automatically by the user id */
+
+/* DSP */
+static struct omap_mbox1_priv omap1_mbox_dsp_priv = {
+	.tx_fifo = {
+		.cmd	= MAILBOX_ARM2DSP1b,
+		.data	= MAILBOX_ARM2DSP1,
+		.flag	= MAILBOX_ARM2DSP1_Flag,
+	},
+	.rx_fifo = {
+		.cmd	= MAILBOX_DSP2ARM1b,
+		.data	= MAILBOX_DSP2ARM1,
+		.flag	= MAILBOX_DSP2ARM1_Flag,
+	},
+};
+
+struct omap_mbox mbox_dsp_info = {
+	.name	= "dsp",
+	.ops	= &omap1_mbox_ops,
+	.priv	= &omap1_mbox_dsp_priv,
+};
+EXPORT_SYMBOL(mbox_dsp_info);
+
+static int __init omap1_mbox_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	int ret = 0;
+
+	if (pdev->num_resources != 2) {
+		dev_err(&pdev->dev, "invalid number of resources: %d\n",
+			pdev->num_resources);
+		return -ENODEV;
+	}
+
+	/* MBOX base */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (unlikely(!res)) {
+		dev_err(&pdev->dev, "invalid mem resource\n");
+		return -ENODEV;
+	}
+	mbox_base = res->start;
+
+	/* DSP IRQ */
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (unlikely(!res)) {
+		dev_err(&pdev->dev, "invalid irq resource\n");
+		return -ENODEV;
+	}
+	mbox_dsp_info.irq = res->start;
+
+	ret = omap_mbox_register(&mbox_dsp_info);
+
+	return ret;
+}
+
+static int omap1_mbox_remove(struct platform_device *pdev)
+{
+	omap_mbox_unregister(&mbox_dsp_info);
+
+	return 0;
+}
+
+static struct platform_driver omap1_mbox_driver = {
+	.probe	= omap1_mbox_probe,
+	.remove	= omap1_mbox_remove,
+	.driver	= {
+		.name	= "mailbox",
+	},
+};
+
+static int __init omap1_mbox_init(void)
+{
+	return platform_driver_register(&omap1_mbox_driver);
+}
+
+static void __exit omap1_mbox_exit(void)
+{
+	platform_driver_unregister(&omap1_mbox_driver);
+}
+
+module_init(omap1_mbox_init);
+module_exit(omap1_mbox_exit);
+
+MODULE_LICENSE("GPL");