arch/arm/mach-omap1/mailbox.c

   1 /*
   2  * Mailbox reservation modules for DSP
   3  *
   4  * Copyright (C) 2006 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/kernel.h>
  13 #include <linux/resource.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/io.h>
  17 #include <mach/mailbox.h>
  18 #include <mach/irqs.h>
  19
  20 #define MAILBOX_ARM2DSP1                0x00
  21 #define MAILBOX_ARM2DSP1b               0x04
  22 #define MAILBOX_DSP2ARM1                0x08
  23 #define MAILBOX_DSP2ARM1b               0x0c
  24 #define MAILBOX_DSP2ARM2                0x10
  25 #define MAILBOX_DSP2ARM2b               0x14
  26 #define MAILBOX_ARM2DSP1_Flag           0x18
  27 #define MAILBOX_DSP2ARM1_Flag           0x1c
  28 #define MAILBOX_DSP2ARM2_Flag           0x20
  29
  30 unsigned long mbox_base;
  31
  32 struct omap_mbox1_fifo {
  33         unsigned long cmd;
  34         unsigned long data;
  35         unsigned long flag;
  36 };
  37
  38 struct omap_mbox1_priv {
  39         struct omap_mbox1_fifo tx_fifo;
  40         struct omap_mbox1_fifo rx_fifo;
  41 };
  42
  43 static inline int mbox_read_reg(unsigned int reg)
  44 {
  45         return __raw_readw(mbox_base + reg);
  46 }
  47
  48 static inline void mbox_write_reg(unsigned int val, unsigned int reg)
  49 {
  50         __raw_writew(val, mbox_base + reg);
  51 }
  52
  53 /* msg */
  54 static mbox_msg_t omap1_mbox_fifo_read(struct omap_mbox *mbox)
  55 {
  56         struct omap_mbox1_fifo *fifo =
  57                 &((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
  58         mbox_msg_t msg;
  59
  60         msg = mbox_read_reg(fifo->data);
  61         msg |= ((mbox_msg_t) mbox_read_reg(fifo->cmd)) << 16;
  62
  63         return msg;
  64 }
  65
  66 static void
  67 omap1_mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
  68 {
  69         struct omap_mbox1_fifo *fifo =
  70                 &((struct omap_mbox1_priv *)mbox->priv)->tx_fifo;
  71
  72         mbox_write_reg(msg & 0xffff, fifo->data);
  73         mbox_write_reg(msg >> 16, fifo->cmd);
  74 }
  75
  76 static int omap1_mbox_fifo_empty(struct omap_mbox *mbox)
  77 {
  78         return 0;
  79 }
  80
  81 static int omap1_mbox_fifo_full(struct omap_mbox *mbox)
  82 {
  83         struct omap_mbox1_fifo *fifo =
  84                 &((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
  85
  86         return (mbox_read_reg(fifo->flag));
  87 }
  88
  89 /* irq */
  90 static void
  91 omap1_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
  92 {
  93         if (irq == IRQ_RX)
  94                 enable_irq(mbox->irq);
  95 }
  96
  97 static void
  98 omap1_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
  99 {
 100         if (irq == IRQ_RX)
 101                 disable_irq(mbox->irq);
 102 }
 103
 104 static int
 105 omap1_mbox_is_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
 106 {
 107         if (irq == IRQ_TX)
 108                 return 0;
 109         return 1;
 110 }
 111
 112 static struct omap_mbox_ops omap1_mbox_ops = {
 113         .type           = OMAP_MBOX_TYPE1,
 114         .fifo_read      = omap1_mbox_fifo_read,
 115         .fifo_write     = omap1_mbox_fifo_write,
 116         .fifo_empty     = omap1_mbox_fifo_empty,
 117         .fifo_full      = omap1_mbox_fifo_full,
 118         .enable_irq     = omap1_mbox_enable_irq,
 119         .disable_irq    = omap1_mbox_disable_irq,
 120         .is_irq         = omap1_mbox_is_irq,
 121 };
 122
 123 /* FIXME: the following struct should be created automatically by the user id */
 124
 125 /* DSP */
 126 static struct omap_mbox1_priv omap1_mbox_dsp_priv = {
 127         .tx_fifo = {
 128                 .cmd    = MAILBOX_ARM2DSP1b,
 129                 .data   = MAILBOX_ARM2DSP1,
 130                 .flag   = MAILBOX_ARM2DSP1_Flag,
 131         },
 132         .rx_fifo = {
 133                 .cmd    = MAILBOX_DSP2ARM1b,
 134                 .data   = MAILBOX_DSP2ARM1,
 135                 .flag   = MAILBOX_DSP2ARM1_Flag,
 136         },
 137 };
 138
 139 struct omap_mbox mbox_dsp_info = {
 140         .name   = "dsp",
 141         .ops    = &omap1_mbox_ops,
 142         .priv   = &omap1_mbox_dsp_priv,
 143 };
 144 EXPORT_SYMBOL(mbox_dsp_info);
 145
 146 static int __init omap1_mbox_probe(struct platform_device *pdev)
 147 {
 148         struct resource *res;
 149         int ret = 0;
 150
 151         if (pdev->num_resources != 2) {
 152                 dev_err(&pdev->dev, "invalid number of resources: %d\n",
 153                         pdev->num_resources);
 154                 return -ENODEV;
 155         }
 156
 157         /* MBOX base */
 158         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 159         if (unlikely(!res)) {
 160                 dev_err(&pdev->dev, "invalid mem resource\n");
 161                 return -ENODEV;
 162         }
 163         mbox_base = res->start;
 164
 165         /* DSP IRQ */
 166         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 167         if (unlikely(!res)) {
 168                 dev_err(&pdev->dev, "invalid irq resource\n");
 169                 return -ENODEV;
 170         }
 171         mbox_dsp_info.irq = res->start;
 172
 173         ret = omap_mbox_register(&mbox_dsp_info);
 174
 175         return ret;
 176 }
 177
 178 static int omap1_mbox_remove(struct platform_device *pdev)
 179 {
 180         omap_mbox_unregister(&mbox_dsp_info);
 181
 182         return 0;
 183 }
 184
 185 static struct platform_driver omap1_mbox_driver = {
 186         .probe  = omap1_mbox_probe,
 187         .remove = omap1_mbox_remove,
 188         .driver = {
 189                 .name   = "mailbox",
 190         },
 191 };
 192
 193 static int __init omap1_mbox_init(void)
 194 {
 195         return platform_driver_register(&omap1_mbox_driver);
 196 }
 197
 198 static void __exit omap1_mbox_exit(void)
 199 {
 200         platform_driver_unregister(&omap1_mbox_driver);
 201 }
 202
 203 module_init(omap1_mbox_init);
 204 module_exit(omap1_mbox_exit);
 205
 206 MODULE_LICENSE("GPL");