arch/arm/mach-omap1/mailbox.c

   1 /*
   2  * Mailbox reservation modules for DSP
   3  *
   4  * Copyright (C) 2006-2008 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 <mach/mailbox.h>
  17 #include <mach/irqs.h>
  18 #include <asm/io.h>
  19
  20 #define DRV_NAME "omap1-mailbox"
  21
  22 #define MAILBOX_ARM2DSP1                0x00
  23 #define MAILBOX_ARM2DSP1b               0x04
  24 #define MAILBOX_DSP2ARM1                0x08
  25 #define MAILBOX_DSP2ARM1b               0x0c
  26 #define MAILBOX_DSP2ARM2                0x10
  27 #define MAILBOX_DSP2ARM2b               0x14
  28 #define MAILBOX_ARM2DSP1_Flag           0x18
  29 #define MAILBOX_DSP2ARM1_Flag           0x1c
  30 #define MAILBOX_DSP2ARM2_Flag           0x20
  31
  32 static void __iomem *mbox_base;
  33
  34 struct omap_mbox1_fifo {
  35         unsigned long cmd;
  36         unsigned long data;
  37         unsigned long flag;
  38 };
  39
  40 struct omap_mbox1_priv {
  41         struct omap_mbox1_fifo tx_fifo;
  42         struct omap_mbox1_fifo rx_fifo;
  43 };
  44
  45 static inline int mbox_read_reg(size_t ofs)
  46 {
  47         return __raw_readw(mbox_base + ofs);
  48 }
  49
  50 static inline void mbox_write_reg(u32 val, size_t ofs)
  51 {
  52         __raw_writew(val, mbox_base + ofs);
  53 }
  54
  55 /* msg */
  56 static mbox_msg_t omap1_mbox_fifo_read(struct omap_mbox *mbox)
  57 {
  58         struct omap_mbox1_fifo *fifo =
  59                 &((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
  60         mbox_msg_t msg;
  61
  62         msg = mbox_read_reg(fifo->data);
  63         msg |= ((mbox_msg_t) mbox_read_reg(fifo->cmd)) << 16;
  64
  65         return msg;
  66 }
  67
  68 static void
  69 omap1_mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
  70 {
  71         struct omap_mbox1_fifo *fifo =
  72                 &((struct omap_mbox1_priv *)mbox->priv)->tx_fifo;
  73
  74         mbox_write_reg(msg & 0xffff, fifo->data);
  75         mbox_write_reg(msg >> 16, fifo->cmd);
  76 }
  77
  78 static int omap1_mbox_fifo_empty(struct omap_mbox *mbox)
  79 {
  80         return 0;
  81 }
  82
  83 static int omap1_mbox_fifo_full(struct omap_mbox *mbox)
  84 {
  85         struct omap_mbox1_fifo *fifo =
  86                 &((struct omap_mbox1_priv *)mbox->priv)->rx_fifo;
  87
  88         return (mbox_read_reg(fifo->flag));
  89 }
  90
  91 /* irq */
  92 static void
  93 omap1_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
  94 {
  95         if (irq == IRQ_RX)
  96                 enable_irq(mbox->irq);
  97 }
  98
  99 static void
 100 omap1_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
 101 {
 102         if (irq == IRQ_RX)
 103                 disable_irq(mbox->irq);
 104 }
 105
 106 static int
 107 omap1_mbox_is_irq(struct omap_mbox *mbox, omap_mbox_type_t irq)
 108 {
 109         if (irq == IRQ_TX)
 110                 return 0;
 111         return 1;
 112 }
 113
 114 static struct omap_mbox_ops omap1_mbox_ops = {
 115         .type           = OMAP_MBOX_TYPE1,
 116         .fifo_read      = omap1_mbox_fifo_read,
 117         .fifo_write     = omap1_mbox_fifo_write,
 118         .fifo_empty     = omap1_mbox_fifo_empty,
 119         .fifo_full      = omap1_mbox_fifo_full,
 120         .enable_irq     = omap1_mbox_enable_irq,
 121         .disable_irq    = omap1_mbox_disable_irq,
 122         .is_irq         = omap1_mbox_is_irq,
 123 };
 124
 125 /* FIXME: the following struct should be created automatically by the user id */
 126
 127 /* DSP */
 128 static struct omap_mbox1_priv omap1_mbox_dsp_priv = {
 129         .tx_fifo = {
 130                 .cmd    = MAILBOX_ARM2DSP1b,
 131                 .data   = MAILBOX_ARM2DSP1,
 132                 .flag   = MAILBOX_ARM2DSP1_Flag,
 133         },
 134         .rx_fifo = {
 135                 .cmd    = MAILBOX_DSP2ARM1b,
 136                 .data   = MAILBOX_DSP2ARM1,
 137                 .flag   = MAILBOX_DSP2ARM1_Flag,
 138         },
 139 };
 140
 141 struct omap_mbox mbox_dsp_info = {
 142         .name   = "dsp",
 143         .ops    = &omap1_mbox_ops,
 144         .priv   = &omap1_mbox_dsp_priv,
 145 };
 146 EXPORT_SYMBOL(mbox_dsp_info);
 147
 148 static int __devinit omap1_mbox_probe(struct platform_device *pdev)
 149 {
 150         struct resource *res;
 151         int ret = 0;
 152
 153         if (pdev->num_resources != 2) {
 154                 dev_err(&pdev->dev, "invalid number of resources: %d\n",
 155                         pdev->num_resources);
 156                 return -ENODEV;
 157         }
 158
 159         /* MBOX base */
 160         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 161         if (unlikely(!res)) {
 162                 dev_err(&pdev->dev, "invalid mem resource\n");
 163                 return -ENODEV;
 164         }
 165         mbox_base = res->start;
 166
 167         /* DSP IRQ */
 168         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 169         if (unlikely(!res)) {
 170                 dev_err(&pdev->dev, "invalid irq resource\n");
 171                 return -ENODEV;
 172         }
 173         mbox_dsp_info.irq = res->start;
 174
 175         return omap_mbox_register(&pdev->dev, &mbox_dsp_info);
 176 }
 177
 178 static int __devexit 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 = __devexit_p(omap1_mbox_remove),
 188         .driver = {
 189                 .name   = DRV_NAME,
 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 v2");
 207 MODULE_DESCRIPTION("omap mailbox: omap1 architecture specific functions");
 208 MODULE_AUTHOR("Hiroshi DOYU" <Hiroshi.DOYU@nokia.com>);
 209 MODULE_ALIAS("platform:"DRV_NAME);