LXR uboot/drivers/mailbox/sandbox-mbox.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2016, NVIDIA CORPORATION.
   4 */
   5
   6#include <common.h>
   7#include <dm.h>
   8#include <mailbox-uclass.h>
   9#include <asm/io.h>
  10#include <asm/mbox.h>
  11
  12#define SANDBOX_MBOX_CHANNELS 2
  13
  14struct sandbox_mbox_chan {
  15        bool rx_msg_valid;
  16        uint32_t rx_msg;
  17};
  18
  19struct sandbox_mbox {
  20        struct sandbox_mbox_chan chans[SANDBOX_MBOX_CHANNELS];
  21};
  22
  23static int sandbox_mbox_request(struct mbox_chan *chan)
  24{
  25        debug("%s(chan=%p)\n", __func__, chan);
  26
  27        if (chan->id >= SANDBOX_MBOX_CHANNELS)
  28                return -EINVAL;
  29
  30        return 0;
  31}
  32
  33static int sandbox_mbox_free(struct mbox_chan *chan)
  34{
  35        debug("%s(chan=%p)\n", __func__, chan);
  36
  37        return 0;
  38}
  39
  40static int sandbox_mbox_send(struct mbox_chan *chan, const void *data)
  41{
  42        struct sandbox_mbox *sbm = dev_get_priv(chan->dev);
  43        const uint32_t *pmsg = data;
  44
  45        debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
  46
  47        sbm->chans[chan->id].rx_msg = *pmsg ^ SANDBOX_MBOX_PING_XOR;
  48        sbm->chans[chan->id].rx_msg_valid = true;
  49
  50        return 0;
  51}
  52
  53static int sandbox_mbox_recv(struct mbox_chan *chan, void *data)
  54{
  55        struct sandbox_mbox *sbm = dev_get_priv(chan->dev);
  56        uint32_t *pmsg = data;
  57
  58        debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
  59
  60        if (!sbm->chans[chan->id].rx_msg_valid)
  61                return -ENODATA;
  62
  63        *pmsg = sbm->chans[chan->id].rx_msg;
  64        sbm->chans[chan->id].rx_msg_valid = false;
  65
  66        return 0;
  67}
  68
  69static int sandbox_mbox_bind(struct udevice *dev)
  70{
  71        debug("%s(dev=%p)\n", __func__, dev);
  72
  73        return 0;
  74}
  75
  76static int sandbox_mbox_probe(struct udevice *dev)
  77{
  78        debug("%s(dev=%p)\n", __func__, dev);
  79
  80        return 0;
  81}
  82
  83static const struct udevice_id sandbox_mbox_ids[] = {
  84        { .compatible = "sandbox,mbox" },
  85        { }
  86};
  87
  88struct mbox_ops sandbox_mbox_mbox_ops = {
  89        .request = sandbox_mbox_request,
  90        .free = sandbox_mbox_free,
  91        .send = sandbox_mbox_send,
  92        .recv = sandbox_mbox_recv,
  93};
  94
  95U_BOOT_DRIVER(sandbox_mbox) = {
  96        .name = "sandbox_mbox",
  97        .id = UCLASS_MAILBOX,
  98        .of_match = sandbox_mbox_ids,
  99        .bind = sandbox_mbox_bind,
 100        .probe = sandbox_mbox_probe,
 101        .priv_auto_alloc_size = sizeof(struct sandbox_mbox),
 102        .ops = &sandbox_mbox_mbox_ops,
 103};
 104