summaryrefslogtreecommitdiff
path: root/drivers/mailbox
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mailbox')
-rw-r--r--drivers/mailbox/Kconfig34
-rw-r--r--drivers/mailbox/Makefile6
-rw-r--r--drivers/mailbox/mailbox-omap1.c203
-rw-r--r--drivers/mailbox/mailbox-omap2.c358
-rw-r--r--drivers/mailbox/omap-mailbox.c469
-rw-r--r--drivers/mailbox/omap-mbox.h67
6 files changed, 1137 insertions, 0 deletions
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 9545c9f03809..c8b5c13bcd05 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -16,4 +16,38 @@ config PL320_MBOX
Management Engine, primarily for cpufreq. Say Y here if you want
to use the PL320 IPCM support.
+config OMAP_MBOX
+ tristate
+ help
+ This option is selected by any OMAP architecture specific mailbox
+ driver such as CONFIG_OMAP1_MBOX or CONFIG_OMAP2PLUS_MBOX. This
+ enables the common OMAP mailbox framework code.
+
+config OMAP1_MBOX
+ tristate "OMAP1 Mailbox framework support"
+ depends on ARCH_OMAP1
+ select OMAP_MBOX
+ help
+ Mailbox implementation for OMAP chips with hardware for
+ interprocessor communication involving DSP in OMAP1. Say Y here
+ if you want to use OMAP1 Mailbox framework support.
+
+config OMAP2PLUS_MBOX
+ tristate "OMAP2+ Mailbox framework support"
+ depends on ARCH_OMAP2PLUS
+ select OMAP_MBOX
+ help
+ Mailbox implementation for OMAP family chips with hardware for
+ interprocessor communication involving DSP, IVA1.0 and IVA2 in
+ OMAP2/3; or IPU, IVA HD and DSP in OMAP4/5. Say Y here if you
+ want to use OMAP2+ Mailbox framework support.
+
+config OMAP_MBOX_KFIFO_SIZE
+ int "Mailbox kfifo default buffer size (bytes)"
+ depends on OMAP2PLUS_MBOX || OMAP1_MBOX
+ default 256
+ help
+ Specify the default size of mailbox's kfifo buffers (bytes).
+ This can also be changed at runtime (via the mbox_kfifo_size
+ module parameter).
endif
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index 543ad6a79505..e0facb34084a 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -1 +1,7 @@
obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o
+
+obj-$(CONFIG_OMAP_MBOX) += omap-mailbox.o
+obj-$(CONFIG_OMAP1_MBOX) += mailbox_omap1.o
+mailbox_omap1-objs := mailbox-omap1.o
+obj-$(CONFIG_OMAP2PLUS_MBOX) += mailbox_omap2.o
+mailbox_omap2-objs := mailbox-omap2.o
diff --git a/drivers/mailbox/mailbox-omap1.c b/drivers/mailbox/mailbox-omap1.c
new file mode 100644
index 000000000000..9001b7633f10
--- /dev/null
+++ b/drivers/mailbox/mailbox-omap1.c
@@ -0,0 +1,203 @@
+/*
+ * Mailbox reservation modules for OMAP1
+ *
+ * Copyright (C) 2006-2009 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/module.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+
+#include "omap-mbox.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
+
+static void __iomem *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(size_t ofs)
+{
+ return __raw_readw(mbox_base + ofs);
+}
+
+static inline void mbox_write_reg(u32 val, size_t ofs)
+{
+ __raw_writew(val, mbox_base + ofs);
+}
+
+/* msg */
+static 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 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 int omap1_mbox_fifo_empty(struct omap_mbox *mbox)
+{
+ return 0;
+}
+
+static 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 void
+omap1_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+ if (irq == IRQ_RX)
+ enable_irq(mbox->irq);
+}
+
+static void
+omap1_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+ if (irq == IRQ_RX)
+ disable_irq(mbox->irq);
+}
+
+static int
+omap1_mbox_is_irq(struct omap_mbox *mbox, omap_mbox_irq_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,
+ },
+};
+
+static struct omap_mbox mbox_dsp_info = {
+ .name = "dsp",
+ .ops = &omap1_mbox_ops,
+ .priv = &omap1_mbox_dsp_priv,
+};
+
+static struct omap_mbox *omap1_mboxes[] = { &mbox_dsp_info, NULL };
+
+static int omap1_mbox_probe(struct platform_device *pdev)
+{
+ struct resource *mem;
+ int ret;
+ struct omap_mbox **list;
+
+ list = omap1_mboxes;
+ list[0]->irq = platform_get_irq_byname(pdev, "dsp");
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem)
+ return -ENOENT;
+
+ mbox_base = ioremap(mem->start, resource_size(mem));
+ if (!mbox_base)
+ return -ENOMEM;
+
+ ret = omap_mbox_register(&pdev->dev, list);
+ if (ret) {
+ iounmap(mbox_base);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int omap1_mbox_remove(struct platform_device *pdev)
+{
+ omap_mbox_unregister();
+ iounmap(mbox_base);
+ return 0;
+}
+
+static struct platform_driver omap1_mbox_driver = {
+ .probe = omap1_mbox_probe,
+ .remove = omap1_mbox_remove,
+ .driver = {
+ .name = "omap-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 v2");
+MODULE_DESCRIPTION("omap mailbox: omap1 architecture specific functions");
+MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>");
+MODULE_ALIAS("platform:omap1-mailbox");
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");
diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c
new file mode 100644
index 000000000000..d79a646b9042
--- /dev/null
+++ b/drivers/mailbox/omap-mailbox.c
@@ -0,0 +1,469 @@
+/*
+ * OMAP mailbox driver
+ *
+ * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/kfifo.h>
+#include <linux/err.h>
+#include <linux/notifier.h>
+#include <linux/module.h>
+
+#include "omap-mbox.h"
+
+static struct omap_mbox **mboxes;
+
+static int mbox_configured;
+static DEFINE_MUTEX(mbox_configured_lock);
+
+static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
+module_param(mbox_kfifo_size, uint, S_IRUGO);
+MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
+
+/* Mailbox FIFO handle functions */
+static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
+{
+ return mbox->ops->fifo_read(mbox);
+}
+static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
+{
+ mbox->ops->fifo_write(mbox, msg);
+}
+static inline int mbox_fifo_empty(struct omap_mbox *mbox)
+{
+ return mbox->ops->fifo_empty(mbox);
+}
+static inline int mbox_fifo_full(struct omap_mbox *mbox)
+{
+ return mbox->ops->fifo_full(mbox);
+}
+
+/* Mailbox IRQ handle functions */
+static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+ if (mbox->ops->ack_irq)
+ mbox->ops->ack_irq(mbox, irq);
+}
+static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+ return mbox->ops->is_irq(mbox, irq);
+}
+
+/*
+ * message sender
+ */
+static int __mbox_poll_for_space(struct omap_mbox *mbox)
+{
+ int ret = 0, i = 1000;
+
+ while (mbox_fifo_full(mbox)) {
+ if (mbox->ops->type == OMAP_MBOX_TYPE2)
+ return -1;
+ if (--i == 0)
+ return -1;
+ udelay(1);
+ }
+ return ret;
+}
+
+int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
+{
+ struct omap_mbox_queue *mq = mbox->txq;
+ int ret = 0, len;
+
+ spin_lock_bh(&mq->lock);
+
+ if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) {
+ mbox_fifo_write(mbox, msg);
+ goto out;
+ }
+
+ len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+ WARN_ON(len != sizeof(msg));
+
+ tasklet_schedule(&mbox->txq->tasklet);
+
+out:
+ spin_unlock_bh(&mq->lock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_mbox_msg_send);
+
+void omap_mbox_save_ctx(struct omap_mbox *mbox)
+{
+ if (!mbox->ops->save_ctx) {
+ dev_err(mbox->dev, "%s:\tno save\n", __func__);
+ return;
+ }
+
+ mbox->ops->save_ctx(mbox);
+}
+EXPORT_SYMBOL(omap_mbox_save_ctx);
+
+void omap_mbox_restore_ctx(struct omap_mbox *mbox)
+{
+ if (!mbox->ops->restore_ctx) {
+ dev_err(mbox->dev, "%s:\tno restore\n", __func__);
+ return;
+ }
+
+ mbox->ops->restore_ctx(mbox);
+}
+EXPORT_SYMBOL(omap_mbox_restore_ctx);
+
+void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+ mbox->ops->enable_irq(mbox, irq);
+}
+EXPORT_SYMBOL(omap_mbox_enable_irq);
+
+void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+ mbox->ops->disable_irq(mbox, irq);
+}
+EXPORT_SYMBOL(omap_mbox_disable_irq);
+
+static void mbox_tx_tasklet(unsigned long tx_data)
+{
+ struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
+ struct omap_mbox_queue *mq = mbox->txq;
+ mbox_msg_t msg;
+ int ret;
+
+ while (kfifo_len(&mq->fifo)) {
+ if (__mbox_poll_for_space(mbox)) {
+ omap_mbox_enable_irq(mbox, IRQ_TX);
+ break;
+ }
+
+ ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
+ sizeof(msg));
+ WARN_ON(ret != sizeof(msg));
+
+ mbox_fifo_write(mbox, msg);
+ }
+}
+
+/*
+ * Message receiver(workqueue)
+ */
+static void mbox_rx_work(struct work_struct *work)
+{
+ struct omap_mbox_queue *mq =
+ container_of(work, struct omap_mbox_queue, work);
+ mbox_msg_t msg;
+ int len;
+
+ while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
+ len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+ WARN_ON(len != sizeof(msg));
+
+ blocking_notifier_call_chain(&mq->mbox->notifier, len,
+ (void *)msg);
+ spin_lock_irq(&mq->lock);
+ if (mq->full) {
+ mq->full = false;
+ omap_mbox_enable_irq(mq->mbox, IRQ_RX);
+ }
+ spin_unlock_irq(&mq->lock);
+ }
+}
+
+/*
+ * Mailbox interrupt handler
+ */
+static void __mbox_tx_interrupt(struct omap_mbox *mbox)
+{
+ omap_mbox_disable_irq(mbox, IRQ_TX);
+ ack_mbox_irq(mbox, IRQ_TX);
+ tasklet_schedule(&mbox->txq->tasklet);
+}
+
+static void __mbox_rx_interrupt(struct omap_mbox *mbox)
+{
+ struct omap_mbox_queue *mq = mbox->rxq;
+ mbox_msg_t msg;
+ int len;
+
+ while (!mbox_fifo_empty(mbox)) {
+ if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
+ omap_mbox_disable_irq(mbox, IRQ_RX);
+ mq->full = true;
+ goto nomem;
+ }
+
+ msg = mbox_fifo_read(mbox);
+
+ len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+ WARN_ON(len != sizeof(msg));
+
+ if (mbox->ops->type == OMAP_MBOX_TYPE1)
+ break;
+ }
+
+ /* no more messages in the fifo. clear IRQ source. */
+ ack_mbox_irq(mbox, IRQ_RX);
+nomem:
+ schedule_work(&mbox->rxq->work);
+}
+
+static irqreturn_t mbox_interrupt(int irq, void *p)
+{
+ struct omap_mbox *mbox = p;
+
+ if (is_mbox_irq(mbox, IRQ_TX))
+ __mbox_tx_interrupt(mbox);
+
+ if (is_mbox_irq(mbox, IRQ_RX))
+ __mbox_rx_interrupt(mbox);
+
+ return IRQ_HANDLED;
+}
+
+static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
+ void (*work) (struct work_struct *),
+ void (*tasklet)(unsigned long))
+{
+ struct omap_mbox_queue *mq;
+
+ mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
+ if (!mq)
+ return NULL;
+
+ spin_lock_init(&mq->lock);
+
+ if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
+ goto error;
+
+ if (work)
+ INIT_WORK(&mq->work, work);
+
+ if (tasklet)
+ tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
+ return mq;
+error:
+ kfree(mq);
+ return NULL;
+}
+
+static void mbox_queue_free(struct omap_mbox_queue *q)
+{
+ kfifo_free(&q->fifo);
+ kfree(q);
+}
+
+static int omap_mbox_startup(struct omap_mbox *mbox)
+{
+ int ret = 0;
+ struct omap_mbox_queue *mq;
+
+ mutex_lock(&mbox_configured_lock);
+ if (!mbox_configured++) {
+ if (likely(mbox->ops->startup)) {
+ ret = mbox->ops->startup(mbox);
+ if (unlikely(ret))
+ goto fail_startup;
+ } else
+ goto fail_startup;
+ }
+
+ if (!mbox->use_count++) {
+ mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
+ if (!mq) {
+ ret = -ENOMEM;
+ goto fail_alloc_txq;
+ }
+ mbox->txq = mq;
+
+ mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
+ if (!mq) {
+ ret = -ENOMEM;
+ goto fail_alloc_rxq;
+ }
+ mbox->rxq = mq;
+ mq->mbox = mbox;
+ ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
+ mbox->name, mbox);
+ if (unlikely(ret)) {
+ pr_err("failed to register mailbox interrupt:%d\n",
+ ret);
+ goto fail_request_irq;
+ }
+
+ omap_mbox_enable_irq(mbox, IRQ_RX);
+ }
+ mutex_unlock(&mbox_configured_lock);
+ return 0;
+
+fail_request_irq:
+ mbox_queue_free(mbox->rxq);
+fail_alloc_rxq:
+ mbox_queue_free(mbox->txq);
+fail_alloc_txq:
+ if (mbox->ops->shutdown)
+ mbox->ops->shutdown(mbox);
+ mbox->use_count--;
+fail_startup:
+ mbox_configured--;
+ mutex_unlock(&mbox_configured_lock);
+ return ret;
+}
+
+static void omap_mbox_fini(struct omap_mbox *mbox)
+{
+ mutex_lock(&mbox_configured_lock);
+
+ if (!--mbox->use_count) {
+ omap_mbox_disable_irq(mbox, IRQ_RX);
+ free_irq(mbox->irq, mbox);
+ tasklet_kill(&mbox->txq->tasklet);
+ flush_work(&mbox->rxq->work);
+ mbox_queue_free(mbox->txq);
+ mbox_queue_free(mbox->rxq);
+ }
+
+ if (likely(mbox->ops->shutdown)) {
+ if (!--mbox_configured)
+ mbox->ops->shutdown(mbox);
+ }
+
+ mutex_unlock(&mbox_configured_lock);
+}
+
+struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
+{
+ struct omap_mbox *_mbox, *mbox = NULL;
+ int i, ret;
+
+ if (!mboxes)
+ return ERR_PTR(-EINVAL);
+
+ for (i = 0; (_mbox = mboxes[i]); i++) {
+ if (!strcmp(_mbox->name, name)) {
+ mbox = _mbox;
+ break;
+ }
+ }
+
+ if (!mbox)
+ return ERR_PTR(-ENOENT);
+
+ if (nb)
+ blocking_notifier_chain_register(&mbox->notifier, nb);
+
+ ret = omap_mbox_startup(mbox);
+ if (ret) {
+ blocking_notifier_chain_unregister(&mbox->notifier, nb);
+ return ERR_PTR(-ENODEV);
+ }
+
+ return mbox;
+}
+EXPORT_SYMBOL(omap_mbox_get);
+
+void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb)
+{
+ blocking_notifier_chain_unregister(&mbox->notifier, nb);
+ omap_mbox_fini(mbox);
+}
+EXPORT_SYMBOL(omap_mbox_put);
+
+static struct class omap_mbox_class = { .name = "mbox", };
+
+int omap_mbox_register(struct device *parent, struct omap_mbox **list)
+{
+ int ret;
+ int i;
+
+ mboxes = list;
+ if (!mboxes)
+ return -EINVAL;
+
+ for (i = 0; mboxes[i]; i++) {
+ struct omap_mbox *mbox = mboxes[i];
+ mbox->dev = device_create(&omap_mbox_class,
+ parent, 0, mbox, "%s", mbox->name);
+ if (IS_ERR(mbox->dev)) {
+ ret = PTR_ERR(mbox->dev);
+ goto err_out;
+ }
+
+ BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
+ }
+ return 0;
+
+err_out:
+ while (i--)
+ device_unregister(mboxes[i]->dev);
+ return ret;
+}
+EXPORT_SYMBOL(omap_mbox_register);
+
+int omap_mbox_unregister(void)
+{
+ int i;
+
+ if (!mboxes)
+ return -EINVAL;
+
+ for (i = 0; mboxes[i]; i++)
+ device_unregister(mboxes[i]->dev);
+ mboxes = NULL;
+ return 0;
+}
+EXPORT_SYMBOL(omap_mbox_unregister);
+
+static int __init omap_mbox_init(void)
+{
+ int err;
+
+ err = class_register(&omap_mbox_class);
+ if (err)
+ return err;
+
+ /* kfifo size sanity check: alignment and minimal size */
+ mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
+ mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
+ sizeof(mbox_msg_t));
+
+ return 0;
+}
+subsys_initcall(omap_mbox_init);
+
+static void __exit omap_mbox_exit(void)
+{
+ class_unregister(&omap_mbox_class);
+}
+module_exit(omap_mbox_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
+MODULE_AUTHOR("Toshihiro Kobayashi");
+MODULE_AUTHOR("Hiroshi DOYU");
diff --git a/drivers/mailbox/omap-mbox.h b/drivers/mailbox/omap-mbox.h
new file mode 100644
index 000000000000..6cd38fc68599
--- /dev/null
+++ b/drivers/mailbox/omap-mbox.h
@@ -0,0 +1,67 @@
+/*
+ * omap-mbox.h: OMAP mailbox internal definitions
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef OMAP_MBOX_H
+#define OMAP_MBOX_H
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/kfifo.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/omap-mailbox.h>
+
+typedef int __bitwise omap_mbox_type_t;
+#define OMAP_MBOX_TYPE1 ((__force omap_mbox_type_t) 1)
+#define OMAP_MBOX_TYPE2 ((__force omap_mbox_type_t) 2)
+
+struct omap_mbox_ops {
+ omap_mbox_type_t type;
+ int (*startup)(struct omap_mbox *mbox);
+ void (*shutdown)(struct omap_mbox *mbox);
+ /* fifo */
+ mbox_msg_t (*fifo_read)(struct omap_mbox *mbox);
+ void (*fifo_write)(struct omap_mbox *mbox, mbox_msg_t msg);
+ int (*fifo_empty)(struct omap_mbox *mbox);
+ int (*fifo_full)(struct omap_mbox *mbox);
+ /* irq */
+ void (*enable_irq)(struct omap_mbox *mbox,
+ omap_mbox_irq_t irq);
+ void (*disable_irq)(struct omap_mbox *mbox,
+ omap_mbox_irq_t irq);
+ void (*ack_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
+ int (*is_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
+ /* ctx */
+ void (*save_ctx)(struct omap_mbox *mbox);
+ void (*restore_ctx)(struct omap_mbox *mbox);
+};
+
+struct omap_mbox_queue {
+ spinlock_t lock;
+ struct kfifo fifo;
+ struct work_struct work;
+ struct tasklet_struct tasklet;
+ struct omap_mbox *mbox;
+ bool full;
+};
+
+struct omap_mbox {
+ const char *name;
+ unsigned int irq;
+ struct omap_mbox_queue *txq, *rxq;
+ struct omap_mbox_ops *ops;
+ struct device *dev;
+ void *priv;
+ int use_count;
+ struct blocking_notifier_head notifier;
+};
+
+int omap_mbox_register(struct device *parent, struct omap_mbox **);
+int omap_mbox_unregister(void);
+
+#endif /* OMAP_MBOX_H */