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