linux/drivers/mailbox/mailbox-omap1.c
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   1/*
   2 * Mailbox reservation modules for OMAP1
   3 *
   4 * Copyright (C) 2006-2009 Nokia Corporation
   5 * Written by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
   6 *
   7 * This file is subject to the terms and conditions of the GNU General Public
   8 * License.  See the file "COPYING" in the main directory of this archive
   9 * for more details.
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/interrupt.h>
  14#include <linux/platform_device.h>
  15#include <linux/io.h>
  16
  17#include "omap-mbox.h"
  18
  19#define MAILBOX_ARM2DSP1                0x00
  20#define MAILBOX_ARM2DSP1b               0x04
  21#define MAILBOX_DSP2ARM1                0x08
  22#define MAILBOX_DSP2ARM1b               0x0c
  23#define MAILBOX_DSP2ARM2                0x10
  24#define MAILBOX_DSP2ARM2b               0x14
  25#define MAILBOX_ARM2DSP1_Flag           0x18
  26#define MAILBOX_DSP2ARM1_Flag           0x1c
  27#define MAILBOX_DSP2ARM2_Flag           0x20
  28
  29static void __iomem *mbox_base;
  30
  31struct omap_mbox1_fifo {
  32        unsigned long cmd;
  33        unsigned long data;
  34        unsigned long flag;
  35};
  36
  37struct omap_mbox1_priv {
  38        struct omap_mbox1_fifo tx_fifo;
  39        struct omap_mbox1_fifo rx_fifo;
  40};
  41
  42static inline int mbox_read_reg(size_t ofs)
  43{
  44        return __raw_readw(mbox_base + ofs);
  45}
  46
  47static inline void mbox_write_reg(u32 val, size_t ofs)
  48{
  49        __raw_writew(val, mbox_base + ofs);
  50}
  51
  52/* msg */
  53static mbox_msg_t omap1_mbox_fifo_read(struct omap_mbox *mbox)
  54{
  55        struct omap_mbox1_fifo *fifo =
  56                &((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
  57        mbox_msg_t msg;
  58
  59        msg = mbox_read_reg(fifo->data);
  60        msg |= ((mbox_msg_t) mbox_read_reg(fifo->cmd)) << 16;
  61
  62        return msg;
  63}
  64
  65static void
  66omap1_mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
  67{
  68        struct omap_mbox1_fifo *fifo =
  69                &((struct omap_mbox1_priv *)mbox->priv)->tx_fifo;
  70
  71        mbox_write_reg(msg & 0xffff, fifo->data);
  72        mbox_write_reg(msg >> 16, fifo->cmd);
  73}
  74
  75static int omap1_mbox_fifo_empty(struct omap_mbox *mbox)
  76{
  77        return 0;
  78}
  79
  80static int omap1_mbox_fifo_full(struct omap_mbox *mbox)
  81{
  82        struct omap_mbox1_fifo *fifo =
  83                &((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
  84
  85        return mbox_read_reg(fifo->flag);
  86}
  87
  88/* irq */
  89static void
  90omap1_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
  91{
  92        if (irq == IRQ_RX)
  93                enable_irq(mbox->irq);
  94}
  95
  96static void
  97omap1_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
  98{
  99        if (irq == IRQ_RX)
 100                disable_irq(mbox->irq);
 101}
 102
 103static int
 104omap1_mbox_is_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 105{
 106        if (irq == IRQ_TX)
 107                return 0;
 108        return 1;
 109}
 110
 111static struct omap_mbox_ops omap1_mbox_ops = {
 112        .type           = OMAP_MBOX_TYPE1,
 113        .fifo_read      = omap1_mbox_fifo_read,
 114        .fifo_write     = omap1_mbox_fifo_write,
 115        .fifo_empty     = omap1_mbox_fifo_empty,
 116        .fifo_full      = omap1_mbox_fifo_full,
 117        .enable_irq     = omap1_mbox_enable_irq,
 118        .disable_irq    = omap1_mbox_disable_irq,
 119        .is_irq         = omap1_mbox_is_irq,
 120};
 121
 122/* FIXME: the following struct should be created automatically by the user id */
 123
 124/* DSP */
 125static struct omap_mbox1_priv omap1_mbox_dsp_priv = {
 126        .tx_fifo = {
 127                .cmd    = MAILBOX_ARM2DSP1b,
 128                .data   = MAILBOX_ARM2DSP1,
 129                .flag   = MAILBOX_ARM2DSP1_Flag,
 130        },
 131        .rx_fifo = {
 132                .cmd    = MAILBOX_DSP2ARM1b,
 133                .data   = MAILBOX_DSP2ARM1,
 134                .flag   = MAILBOX_DSP2ARM1_Flag,
 135        },
 136};
 137
 138static struct omap_mbox mbox_dsp_info = {
 139        .name   = "dsp",
 140        .ops    = &omap1_mbox_ops,
 141        .priv   = &omap1_mbox_dsp_priv,
 142};
 143
 144static struct omap_mbox *omap1_mboxes[] = { &mbox_dsp_info, NULL };
 145
 146static int omap1_mbox_probe(struct platform_device *pdev)
 147{
 148        struct resource *mem;
 149        int ret;
 150        struct omap_mbox **list;
 151
 152        list = omap1_mboxes;
 153        list[0]->irq = platform_get_irq_byname(pdev, "dsp");
 154
 155        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 156        if (!mem)
 157                return -ENOENT;
 158
 159        mbox_base = ioremap(mem->start, resource_size(mem));
 160        if (!mbox_base)
 161                return -ENOMEM;
 162
 163        ret = omap_mbox_register(&pdev->dev, list);
 164        if (ret) {
 165                iounmap(mbox_base);
 166                return ret;
 167        }
 168
 169        return 0;
 170}
 171
 172static int omap1_mbox_remove(struct platform_device *pdev)
 173{
 174        omap_mbox_unregister();
 175        iounmap(mbox_base);
 176        return 0;
 177}
 178
 179static struct platform_driver omap1_mbox_driver = {
 180        .probe  = omap1_mbox_probe,
 181        .remove = omap1_mbox_remove,
 182        .driver = {
 183                .name   = "omap-mailbox",
 184        },
 185};
 186
 187static int __init omap1_mbox_init(void)
 188{
 189        return platform_driver_register(&omap1_mbox_driver);
 190}
 191
 192static void __exit omap1_mbox_exit(void)
 193{
 194        platform_driver_unregister(&omap1_mbox_driver);
 195}
 196
 197module_init(omap1_mbox_init);
 198module_exit(omap1_mbox_exit);
 199
 200MODULE_LICENSE("GPL v2");
 201MODULE_DESCRIPTION("omap mailbox: omap1 architecture specific functions");
 202MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>");
 203MODULE_ALIAS("platform:omap1-mailbox");
 204