drivers/mailbox/mailbox-omap1.c

   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
  29 static void __iomem *mbox_base;
  30
  31 struct omap_mbox1_fifo {
  32         unsigned long cmd;
  33         unsigned long data;
  34         unsigned long flag;
  35 };
  36
  37 struct omap_mbox1_priv {
  38         struct omap_mbox1_fifo tx_fifo;
  39         struct omap_mbox1_fifo rx_fifo;
  40 };
  41
  42 static inline int mbox_read_reg(size_t ofs)
  43 {
  44         return __raw_readw(mbox_base + ofs);
  45 }
  46
  47 static inline void mbox_write_reg(u32 val, size_t ofs)
  48 {
  49         __raw_writew(val, mbox_base + ofs);
  50 }
  51
  52 /* msg */
  53 static 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
  65 static void
  66 omap1_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
  75 static int omap1_mbox_fifo_empty(struct omap_mbox *mbox)
  76 {
  77         return 0;
  78 }
  79
  80 static 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 */
  89 static void
  90 omap1_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
  96 static void
  97 omap1_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
 103 static int
 104 omap1_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
 111 static 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 */
 125 static 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
 138 static struct omap_mbox mbox_dsp_info = {
 139         .name   = "dsp",
 140         .ops    = &omap1_mbox_ops,
 141         .priv   = &omap1_mbox_dsp_priv,
 142 };
 143
 144 static struct omap_mbox *omap1_mboxes[] = { &mbox_dsp_info, NULL };
 145
 146 static 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
 172 static int omap1_mbox_remove(struct platform_device *pdev)
 173 {
 174         omap_mbox_unregister();
 175         iounmap(mbox_base);
 176         return 0;
 177 }
 178
 179 static 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
 187 static int __init omap1_mbox_init(void)
 188 {
 189         return platform_driver_register(&omap1_mbox_driver);
 190 }
 191
 192 static void __exit omap1_mbox_exit(void)
 193 {
 194         platform_driver_unregister(&omap1_mbox_driver);
 195 }
 196
 197 module_init(omap1_mbox_init);
 198 module_exit(omap1_mbox_exit);
 199
 200 MODULE_LICENSE("GPL v2");
 201 MODULE_DESCRIPTION("omap mailbox: omap1 architecture specific functions");
 202 MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>");
 203 MODULE_ALIAS("platform:omap1-mailbox");