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