linux/drivers/mailbox/mailbox-omap2.c
<<
>>
Prefs
   1/*
   2 * Mailbox reservation modules for OMAP2/3
   3 *
   4 * Copyright (C) 2006-2009 Nokia Corporation
   5 * Written by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
   6 *        and  Paul Mundt
   7 *
   8 * This file is subject to the terms and conditions of the GNU General Public
   9 * License.  See the file "COPYING" in the main directory of this archive
  10 * for more details.
  11 */
  12
  13#include <linux/module.h>
  14#include <linux/slab.h>
  15#include <linux/clk.h>
  16#include <linux/err.h>
  17#include <linux/platform_device.h>
  18#include <linux/io.h>
  19#include <linux/pm_runtime.h>
  20#include <linux/platform_data/mailbox-omap.h>
  21
  22#include "omap-mbox.h"
  23
  24#define MAILBOX_REVISION                0x000
  25#define MAILBOX_MESSAGE(m)              (0x040 + 4 * (m))
  26#define MAILBOX_FIFOSTATUS(m)           (0x080 + 4 * (m))
  27#define MAILBOX_MSGSTATUS(m)            (0x0c0 + 4 * (m))
  28#define MAILBOX_IRQSTATUS(u)            (0x100 + 8 * (u))
  29#define MAILBOX_IRQENABLE(u)            (0x104 + 8 * (u))
  30
  31#define OMAP4_MAILBOX_IRQSTATUS(u)      (0x104 + 0x10 * (u))
  32#define OMAP4_MAILBOX_IRQENABLE(u)      (0x108 + 0x10 * (u))
  33#define OMAP4_MAILBOX_IRQENABLE_CLR(u)  (0x10c + 0x10 * (u))
  34
  35#define MAILBOX_IRQ_NEWMSG(m)           (1 << (2 * (m)))
  36#define MAILBOX_IRQ_NOTFULL(m)          (1 << (2 * (m) + 1))
  37
  38#define MBOX_REG_SIZE                   0x120
  39
  40#define OMAP4_MBOX_REG_SIZE             0x130
  41
  42#define MBOX_NR_REGS                    (MBOX_REG_SIZE / sizeof(u32))
  43#define OMAP4_MBOX_NR_REGS              (OMAP4_MBOX_REG_SIZE / sizeof(u32))
  44
  45static void __iomem *mbox_base;
  46
  47struct omap_mbox2_fifo {
  48        unsigned long msg;
  49        unsigned long fifo_stat;
  50        unsigned long msg_stat;
  51};
  52
  53struct omap_mbox2_priv {
  54        struct omap_mbox2_fifo tx_fifo;
  55        struct omap_mbox2_fifo rx_fifo;
  56        unsigned long irqenable;
  57        unsigned long irqstatus;
  58        u32 newmsg_bit;
  59        u32 notfull_bit;
  60        u32 ctx[OMAP4_MBOX_NR_REGS];
  61        unsigned long irqdisable;
  62        u32 intr_type;
  63};
  64
  65static inline unsigned int mbox_read_reg(size_t ofs)
  66{
  67        return __raw_readl(mbox_base + ofs);
  68}
  69
  70static inline void mbox_write_reg(u32 val, size_t ofs)
  71{
  72        __raw_writel(val, mbox_base + ofs);
  73}
  74
  75/* Mailbox H/W preparations */
  76static int omap2_mbox_startup(struct omap_mbox *mbox)
  77{
  78        u32 l;
  79
  80        pm_runtime_enable(mbox->dev->parent);
  81        pm_runtime_get_sync(mbox->dev->parent);
  82
  83        l = mbox_read_reg(MAILBOX_REVISION);
  84        pr_debug("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4, (l & 0x0f));
  85
  86        return 0;
  87}
  88
  89static void omap2_mbox_shutdown(struct omap_mbox *mbox)
  90{
  91        pm_runtime_put_sync(mbox->dev->parent);
  92        pm_runtime_disable(mbox->dev->parent);
  93}
  94
  95/* Mailbox FIFO handle functions */
  96static mbox_msg_t omap2_mbox_fifo_read(struct omap_mbox *mbox)
  97{
  98        struct omap_mbox2_fifo *fifo =
  99                &((struct omap_mbox2_priv *)mbox->priv)->rx_fifo;
 100        return (mbox_msg_t) mbox_read_reg(fifo->msg);
 101}
 102
 103static void omap2_mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
 104{
 105        struct omap_mbox2_fifo *fifo =
 106                &((struct omap_mbox2_priv *)mbox->priv)->tx_fifo;
 107        mbox_write_reg(msg, fifo->msg);
 108}
 109
 110static int omap2_mbox_fifo_empty(struct omap_mbox *mbox)
 111{
 112        struct omap_mbox2_fifo *fifo =
 113                &((struct omap_mbox2_priv *)mbox->priv)->rx_fifo;
 114        return (mbox_read_reg(fifo->msg_stat) == 0);
 115}
 116
 117static int omap2_mbox_fifo_full(struct omap_mbox *mbox)
 118{
 119        struct omap_mbox2_fifo *fifo =
 120                &((struct omap_mbox2_priv *)mbox->priv)->tx_fifo;
 121        return mbox_read_reg(fifo->fifo_stat);
 122}
 123
 124/* Mailbox IRQ handle functions */
 125static void omap2_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 126{
 127        struct omap_mbox2_priv *p = mbox->priv;
 128        u32 l, bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
 129
 130        l = mbox_read_reg(p->irqenable);
 131        l |= bit;
 132        mbox_write_reg(l, p->irqenable);
 133}
 134
 135static void omap2_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 136{
 137        struct omap_mbox2_priv *p = mbox->priv;
 138        u32 bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
 139
 140        /*
 141         * Read and update the interrupt configuration register for pre-OMAP4.
 142         * OMAP4 and later SoCs have a dedicated interrupt disabling register.
 143         */
 144        if (!p->intr_type)
 145                bit = mbox_read_reg(p->irqdisable) & ~bit;
 146
 147        mbox_write_reg(bit, p->irqdisable);
 148}
 149
 150static void omap2_mbox_ack_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 151{
 152        struct omap_mbox2_priv *p = mbox->priv;
 153        u32 bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
 154
 155        mbox_write_reg(bit, p->irqstatus);
 156
 157        /* Flush posted write for irq status to avoid spurious interrupts */
 158        mbox_read_reg(p->irqstatus);
 159}
 160
 161static int omap2_mbox_is_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 162{
 163        struct omap_mbox2_priv *p = mbox->priv;
 164        u32 bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
 165        u32 enable = mbox_read_reg(p->irqenable);
 166        u32 status = mbox_read_reg(p->irqstatus);
 167
 168        return (int)(enable & status & bit);
 169}
 170
 171static void omap2_mbox_save_ctx(struct omap_mbox *mbox)
 172{
 173        int i;
 174        struct omap_mbox2_priv *p = mbox->priv;
 175        int nr_regs;
 176
 177        if (p->intr_type)
 178                nr_regs = OMAP4_MBOX_NR_REGS;
 179        else
 180                nr_regs = MBOX_NR_REGS;
 181        for (i = 0; i < nr_regs; i++) {
 182                p->ctx[i] = mbox_read_reg(i * sizeof(u32));
 183
 184                dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
 185                        i, p->ctx[i]);
 186        }
 187}
 188
 189static void omap2_mbox_restore_ctx(struct omap_mbox *mbox)
 190{
 191        int i;
 192        struct omap_mbox2_priv *p = mbox->priv;
 193        int nr_regs;
 194
 195        if (p->intr_type)
 196                nr_regs = OMAP4_MBOX_NR_REGS;
 197        else
 198                nr_regs = MBOX_NR_REGS;
 199        for (i = 0; i < nr_regs; i++) {
 200                mbox_write_reg(p->ctx[i], i * sizeof(u32));
 201
 202                dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
 203                        i, p->ctx[i]);
 204        }
 205}
 206
 207static struct omap_mbox_ops omap2_mbox_ops = {
 208        .type           = OMAP_MBOX_TYPE2,
 209        .startup        = omap2_mbox_startup,
 210        .shutdown       = omap2_mbox_shutdown,
 211        .fifo_read      = omap2_mbox_fifo_read,
 212        .fifo_write     = omap2_mbox_fifo_write,
 213        .fifo_empty     = omap2_mbox_fifo_empty,
 214        .fifo_full      = omap2_mbox_fifo_full,
 215        .enable_irq     = omap2_mbox_enable_irq,
 216        .disable_irq    = omap2_mbox_disable_irq,
 217        .ack_irq        = omap2_mbox_ack_irq,
 218        .is_irq         = omap2_mbox_is_irq,
 219        .save_ctx       = omap2_mbox_save_ctx,
 220        .restore_ctx    = omap2_mbox_restore_ctx,
 221};
 222
 223static int omap2_mbox_probe(struct platform_device *pdev)
 224{
 225        struct resource *mem;
 226        int ret;
 227        struct omap_mbox **list, *mbox, *mboxblk;
 228        struct omap_mbox2_priv *priv, *privblk;
 229        struct omap_mbox_pdata *pdata = pdev->dev.platform_data;
 230        struct omap_mbox_dev_info *info;
 231        int i;
 232
 233        if (!pdata || !pdata->info_cnt || !pdata->info) {
 234                pr_err("%s: platform not supported\n", __func__);
 235                return -ENODEV;
 236        }
 237
 238        /* allocate one extra for marking end of list */
 239        list = kzalloc((pdata->info_cnt + 1) * sizeof(*list), GFP_KERNEL);
 240        if (!list)
 241                return -ENOMEM;
 242
 243        mboxblk = mbox = kzalloc(pdata->info_cnt * sizeof(*mbox), GFP_KERNEL);
 244        if (!mboxblk) {
 245                ret = -ENOMEM;
 246                goto free_list;
 247        }
 248
 249        privblk = priv = kzalloc(pdata->info_cnt * sizeof(*priv), GFP_KERNEL);
 250        if (!privblk) {
 251                ret = -ENOMEM;
 252                goto free_mboxblk;
 253        }
 254
 255        info = pdata->info;
 256        for (i = 0; i < pdata->info_cnt; i++, info++, priv++) {
 257                priv->tx_fifo.msg = MAILBOX_MESSAGE(info->tx_id);
 258                priv->tx_fifo.fifo_stat = MAILBOX_FIFOSTATUS(info->tx_id);
 259                priv->rx_fifo.msg =  MAILBOX_MESSAGE(info->rx_id);
 260                priv->rx_fifo.msg_stat =  MAILBOX_MSGSTATUS(info->rx_id);
 261                priv->notfull_bit = MAILBOX_IRQ_NOTFULL(info->tx_id);
 262                priv->newmsg_bit = MAILBOX_IRQ_NEWMSG(info->rx_id);
 263                if (pdata->intr_type) {
 264                        priv->irqenable = OMAP4_MAILBOX_IRQENABLE(info->usr_id);
 265                        priv->irqstatus = OMAP4_MAILBOX_IRQSTATUS(info->usr_id);
 266                        priv->irqdisable =
 267                                OMAP4_MAILBOX_IRQENABLE_CLR(info->usr_id);
 268                } else {
 269                        priv->irqenable = MAILBOX_IRQENABLE(info->usr_id);
 270                        priv->irqstatus = MAILBOX_IRQSTATUS(info->usr_id);
 271                        priv->irqdisable = MAILBOX_IRQENABLE(info->usr_id);
 272                }
 273                priv->intr_type = pdata->intr_type;
 274
 275                mbox->priv = priv;
 276                mbox->name = info->name;
 277                mbox->ops = &omap2_mbox_ops;
 278                mbox->irq = platform_get_irq(pdev, info->irq_id);
 279                if (mbox->irq < 0) {
 280                        ret = mbox->irq;
 281                        goto free_privblk;
 282                }
 283                list[i] = mbox++;
 284        }
 285
 286        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 287        if (!mem) {
 288                ret = -ENOENT;
 289                goto free_privblk;
 290        }
 291
 292        mbox_base = ioremap(mem->start, resource_size(mem));
 293        if (!mbox_base) {
 294                ret = -ENOMEM;
 295                goto free_privblk;
 296        }
 297
 298        ret = omap_mbox_register(&pdev->dev, list);
 299        if (ret)
 300                goto unmap_mbox;
 301        platform_set_drvdata(pdev, list);
 302
 303        return 0;
 304
 305unmap_mbox:
 306        iounmap(mbox_base);
 307free_privblk:
 308        kfree(privblk);
 309free_mboxblk:
 310        kfree(mboxblk);
 311free_list:
 312        kfree(list);
 313        return ret;
 314}
 315
 316static int omap2_mbox_remove(struct platform_device *pdev)
 317{
 318        struct omap_mbox2_priv *privblk;
 319        struct omap_mbox **list = platform_get_drvdata(pdev);
 320        struct omap_mbox *mboxblk = list[0];
 321
 322        privblk = mboxblk->priv;
 323        omap_mbox_unregister();
 324        iounmap(mbox_base);
 325        kfree(privblk);
 326        kfree(mboxblk);
 327        kfree(list);
 328        platform_set_drvdata(pdev, NULL);
 329
 330        return 0;
 331}
 332
 333static struct platform_driver omap2_mbox_driver = {
 334        .probe  = omap2_mbox_probe,
 335        .remove = omap2_mbox_remove,
 336        .driver = {
 337                .name = "omap-mailbox",
 338        },
 339};
 340
 341static int __init omap2_mbox_init(void)
 342{
 343        return platform_driver_register(&omap2_mbox_driver);
 344}
 345
 346static void __exit omap2_mbox_exit(void)
 347{
 348        platform_driver_unregister(&omap2_mbox_driver);
 349}
 350
 351module_init(omap2_mbox_init);
 352module_exit(omap2_mbox_exit);
 353
 354MODULE_LICENSE("GPL v2");
 355MODULE_DESCRIPTION("omap mailbox: omap2/3/4 architecture specific functions");
 356MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>");
 357MODULE_AUTHOR("Paul Mundt");
 358MODULE_ALIAS("platform:omap2-mailbox");
 359