mailbox/omap: move the OMAP mailbox framework to drivers

The mailbox hardware (in OMAP) uses a queued mailbox interrupt
mechanism that provides a communication channel between processors
through a set of registers and their associated interrupt signals
by sending and receiving messages.

The OMAP mailbox framework/driver code is moved to be under
drivers/mailbox, in preparation for adapting to a common mailbox
driver framework. This allows the build for OMAP mailbox to be
enabled (it was disabled during the multi-platform support).

As part of the migration from plat and mach code:
- Kconfig symbols have been renamed to build OMAP1 or OMAP2+ drivers.
- mailbox.h under plat-omap/plat/include has been split into a public
  and private header files. The public header has only the API related
  functions and types.
- The module name mailbox.ko from plat-omap is changed to
  omap-mailbox.ko
- The module name mailbox_mach.ko from mach-omapX is changed as
    mailbox_omap1.ko for OMAP1
    mailbox_omap2.ko for OMAP2+

Cc: Tony Lindgren <tony@atomide.com>
[gregkh@linuxfoundation.org: ack for staging part]
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Omar Ramirez Luna <omar.ramirez@copitl.com>
Signed-off-by: Suman Anna <s-anna@ti.com>

1 files changed, 358 insertions, 0 deletions

diff --git a/drivers/mailbox/mailbox-omap2.c b/drivers/mailbox/mailbox-omap2.c
new file mode 100644
index 000000000000..eba380d7b17f
--- /dev/null
+++ b/drivers/mailbox/mailbox-omap2.c
@@ -0,0 +1,358 @@
+/*
+ * Mailbox reservation modules for OMAP2/3
+ *
+ * Copyright (C) 2006-2009 Nokia Corporation
+ * Written by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
+ *        and  Paul Mundt
+ *
+ * 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/module.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/pm_runtime.h>
+#include <linux/platform_data/mailbox-omap.h>
+
+#include "omap-mbox.h"
+
+#define MAILBOX_REVISION		0x000
+#define MAILBOX_MESSAGE(m)		(0x040 + 4 * (m))
+#define MAILBOX_FIFOSTATUS(m)		(0x080 + 4 * (m))
+#define MAILBOX_MSGSTATUS(m)		(0x0c0 + 4 * (m))
+#define MAILBOX_IRQSTATUS(u)		(0x100 + 8 * (u))
+#define MAILBOX_IRQENABLE(u)		(0x104 + 8 * (u))
+
+#define OMAP4_MAILBOX_IRQSTATUS(u)	(0x104 + 0x10 * (u))
+#define OMAP4_MAILBOX_IRQENABLE(u)	(0x108 + 0x10 * (u))
+#define OMAP4_MAILBOX_IRQENABLE_CLR(u)	(0x10c + 0x10 * (u))
+
+#define MAILBOX_IRQ_NEWMSG(m)		(1 << (2 * (m)))
+#define MAILBOX_IRQ_NOTFULL(m)		(1 << (2 * (m) + 1))
+
+#define MBOX_REG_SIZE			0x120
+
+#define OMAP4_MBOX_REG_SIZE		0x130
+
+#define MBOX_NR_REGS			(MBOX_REG_SIZE / sizeof(u32))
+#define OMAP4_MBOX_NR_REGS		(OMAP4_MBOX_REG_SIZE / sizeof(u32))
+
+static void __iomem *mbox_base;
+
+struct omap_mbox2_fifo {
+	unsigned long msg;
+	unsigned long fifo_stat;
+	unsigned long msg_stat;
+};
+
+struct omap_mbox2_priv {
+	struct omap_mbox2_fifo tx_fifo;
+	struct omap_mbox2_fifo rx_fifo;
+	unsigned long irqenable;
+	unsigned long irqstatus;
+	u32 newmsg_bit;
+	u32 notfull_bit;
+	u32 ctx[OMAP4_MBOX_NR_REGS];
+	unsigned long irqdisable;
+	u32 intr_type;
+};
+
+static inline unsigned int mbox_read_reg(size_t ofs)
+{
+	return __raw_readl(mbox_base + ofs);
+}
+
+static inline void mbox_write_reg(u32 val, size_t ofs)
+{
+	__raw_writel(val, mbox_base + ofs);
+}
+
+/* Mailbox H/W preparations */
+static int omap2_mbox_startup(struct omap_mbox *mbox)
+{
+	u32 l;
+
+	pm_runtime_enable(mbox->dev->parent);
+	pm_runtime_get_sync(mbox->dev->parent);
+
+	l = mbox_read_reg(MAILBOX_REVISION);
+	pr_debug("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4, (l & 0x0f));
+
+	return 0;
+}
+
+static void omap2_mbox_shutdown(struct omap_mbox *mbox)
+{
+	pm_runtime_put_sync(mbox->dev->parent);
+	pm_runtime_disable(mbox->dev->parent);
+}
+
+/* Mailbox FIFO handle functions */
+static mbox_msg_t omap2_mbox_fifo_read(struct omap_mbox *mbox)
+{
+	struct omap_mbox2_fifo *fifo =
+		&((struct omap_mbox2_priv *)mbox->priv)->rx_fifo;
+	return (mbox_msg_t) mbox_read_reg(fifo->msg);
+}
+
+static void omap2_mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
+{
+	struct omap_mbox2_fifo *fifo =
+		&((struct omap_mbox2_priv *)mbox->priv)->tx_fifo;
+	mbox_write_reg(msg, fifo->msg);
+}
+
+static int omap2_mbox_fifo_empty(struct omap_mbox *mbox)
+{
+	struct omap_mbox2_fifo *fifo =
+		&((struct omap_mbox2_priv *)mbox->priv)->rx_fifo;
+	return (mbox_read_reg(fifo->msg_stat) == 0);
+}
+
+static int omap2_mbox_fifo_full(struct omap_mbox *mbox)
+{
+	struct omap_mbox2_fifo *fifo =
+		&((struct omap_mbox2_priv *)mbox->priv)->tx_fifo;
+	return mbox_read_reg(fifo->fifo_stat);
+}
+
+/* Mailbox IRQ handle functions */
+static void omap2_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+	struct omap_mbox2_priv *p = mbox->priv;
+	u32 l, bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
+
+	l = mbox_read_reg(p->irqenable);
+	l |= bit;
+	mbox_write_reg(l, p->irqenable);
+}
+
+static void omap2_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+	struct omap_mbox2_priv *p = mbox->priv;
+	u32 bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
+
+	/*
+	 * Read and update the interrupt configuration register for pre-OMAP4.
+	 * OMAP4 and later SoCs have a dedicated interrupt disabling register.
+	 */
+	if (!p->intr_type)
+		bit = mbox_read_reg(p->irqdisable) & ~bit;
+
+	mbox_write_reg(bit, p->irqdisable);
+}
+
+static void omap2_mbox_ack_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+	struct omap_mbox2_priv *p = mbox->priv;
+	u32 bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
+
+	mbox_write_reg(bit, p->irqstatus);
+
+	/* Flush posted write for irq status to avoid spurious interrupts */
+	mbox_read_reg(p->irqstatus);
+}
+
+static int omap2_mbox_is_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+	struct omap_mbox2_priv *p = mbox->priv;
+	u32 bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
+	u32 enable = mbox_read_reg(p->irqenable);
+	u32 status = mbox_read_reg(p->irqstatus);
+
+	return (int)(enable & status & bit);
+}
+
+static void omap2_mbox_save_ctx(struct omap_mbox *mbox)
+{
+	int i;
+	struct omap_mbox2_priv *p = mbox->priv;
+	int nr_regs;
+
+	if (p->intr_type)
+		nr_regs = OMAP4_MBOX_NR_REGS;
+	else
+		nr_regs = MBOX_NR_REGS;
+	for (i = 0; i < nr_regs; i++) {
+		p->ctx[i] = mbox_read_reg(i * sizeof(u32));
+
+		dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
+			i, p->ctx[i]);
+	}
+}
+
+static void omap2_mbox_restore_ctx(struct omap_mbox *mbox)
+{
+	int i;
+	struct omap_mbox2_priv *p = mbox->priv;
+	int nr_regs;
+
+	if (p->intr_type)
+		nr_regs = OMAP4_MBOX_NR_REGS;
+	else
+		nr_regs = MBOX_NR_REGS;
+	for (i = 0; i < nr_regs; i++) {
+		mbox_write_reg(p->ctx[i], i * sizeof(u32));
+
+		dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
+			i, p->ctx[i]);
+	}
+}
+
+static struct omap_mbox_ops omap2_mbox_ops = {
+	.type		= OMAP_MBOX_TYPE2,
+	.startup	= omap2_mbox_startup,
+	.shutdown	= omap2_mbox_shutdown,
+	.fifo_read	= omap2_mbox_fifo_read,
+	.fifo_write	= omap2_mbox_fifo_write,
+	.fifo_empty	= omap2_mbox_fifo_empty,
+	.fifo_full	= omap2_mbox_fifo_full,
+	.enable_irq	= omap2_mbox_enable_irq,
+	.disable_irq	= omap2_mbox_disable_irq,
+	.ack_irq	= omap2_mbox_ack_irq,
+	.is_irq		= omap2_mbox_is_irq,
+	.save_ctx	= omap2_mbox_save_ctx,
+	.restore_ctx	= omap2_mbox_restore_ctx,
+};
+
+static int omap2_mbox_probe(struct platform_device *pdev)
+{
+	struct resource *mem;
+	int ret;
+	struct omap_mbox **list, *mbox, *mboxblk;
+	struct omap_mbox2_priv *priv, *privblk;
+	struct omap_mbox_pdata *pdata = pdev->dev.platform_data;
+	struct omap_mbox_dev_info *info;
+	int i;
+
+	if (!pdata || !pdata->info_cnt || !pdata->info) {
+		pr_err("%s: platform not supported\n", __func__);
+		return -ENODEV;
+	}
+
+	/* allocate one extra for marking end of list */
+	list = kzalloc((pdata->info_cnt + 1) * sizeof(*list), GFP_KERNEL);
+	if (!list)
+		return -ENOMEM;
+
+	mboxblk = mbox = kzalloc(pdata->info_cnt * sizeof(*mbox), GFP_KERNEL);
+	if (!mboxblk) {
+		ret = -ENOMEM;
+		goto free_list;
+	}
+
+	privblk = priv = kzalloc(pdata->info_cnt * sizeof(*priv), GFP_KERNEL);
+	if (!privblk) {
+		ret = -ENOMEM;
+		goto free_mboxblk;
+	}
+
+	info = pdata->info;
+	for (i = 0; i < pdata->info_cnt; i++, info++, priv++) {
+		priv->tx_fifo.msg = MAILBOX_MESSAGE(info->tx_id);
+		priv->tx_fifo.fifo_stat = MAILBOX_FIFOSTATUS(info->tx_id);
+		priv->rx_fifo.msg =  MAILBOX_MESSAGE(info->rx_id);
+		priv->rx_fifo.msg_stat =  MAILBOX_MSGSTATUS(info->rx_id);
+		priv->notfull_bit = MAILBOX_IRQ_NOTFULL(info->tx_id);
+		priv->newmsg_bit = MAILBOX_IRQ_NEWMSG(info->rx_id);
+		if (pdata->intr_type) {
+			priv->irqenable = OMAP4_MAILBOX_IRQENABLE(info->usr_id);
+			priv->irqstatus = OMAP4_MAILBOX_IRQSTATUS(info->usr_id);
+			priv->irqdisable =
+				OMAP4_MAILBOX_IRQENABLE_CLR(info->usr_id);
+		} else {
+			priv->irqenable = MAILBOX_IRQENABLE(info->usr_id);
+			priv->irqstatus = MAILBOX_IRQSTATUS(info->usr_id);
+			priv->irqdisable = MAILBOX_IRQENABLE(info->usr_id);
+		}
+		priv->intr_type = pdata->intr_type;
+
+		mbox->priv = priv;
+		mbox->name = info->name;
+		mbox->ops = &omap2_mbox_ops;
+		mbox->irq = platform_get_irq(pdev, info->irq_id);
+		if (mbox->irq < 0) {
+			ret = mbox->irq;
+			goto free_privblk;
+		}
+		list[i] = mbox++;
+	}
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		ret = -ENOENT;
+		goto free_privblk;
+	}
+
+	mbox_base = ioremap(mem->start, resource_size(mem));
+	if (!mbox_base) {
+		ret = -ENOMEM;
+		goto free_privblk;
+	}
+
+	ret = omap_mbox_register(&pdev->dev, list);
+	if (ret)
+		goto unmap_mbox;
+	platform_set_drvdata(pdev, list);
+
+	return 0;
+
+unmap_mbox:
+	iounmap(mbox_base);
+free_privblk:
+	kfree(privblk);
+free_mboxblk:
+	kfree(mboxblk);
+free_list:
+	kfree(list);
+	return ret;
+}
+
+static int omap2_mbox_remove(struct platform_device *pdev)
+{
+	struct omap_mbox2_priv *privblk;
+	struct omap_mbox **list = platform_get_drvdata(pdev);
+	struct omap_mbox *mboxblk = list[0];
+
+	privblk = mboxblk->priv;
+	omap_mbox_unregister();
+	iounmap(mbox_base);
+	kfree(privblk);
+	kfree(mboxblk);
+	kfree(list);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+static struct platform_driver omap2_mbox_driver = {
+	.probe	= omap2_mbox_probe,
+	.remove	= omap2_mbox_remove,
+	.driver	= {
+		.name = "omap-mailbox",
+	},
+};
+
+static int __init omap2_mbox_init(void)
+{
+	return platform_driver_register(&omap2_mbox_driver);
+}
+
+static void __exit omap2_mbox_exit(void)
+{
+	platform_driver_unregister(&omap2_mbox_driver);
+}
+
+module_init(omap2_mbox_init);
+module_exit(omap2_mbox_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("omap mailbox: omap2/3/4 architecture specific functions");
+MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>");
+MODULE_AUTHOR("Paul Mundt");
+MODULE_ALIAS("platform:omap2-mailbox");