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 14 struct sandbox_mbox_chan { 15 bool rx_msg_valid; 16 uint32_t rx_msg; 17 }; 18 19 struct sandbox_mbox { 20 struct sandbox_mbox_chan chans[SANDBOX_MBOX_CHANNELS]; 21 }; 22 23 static 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 33 static int sandbox_mbox_free(struct mbox_chan *chan) 34 { 35 debug("%s(chan=%p)\n", __func__, chan); 36 37 return 0; 38 } 39 40 static 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 53 static 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 69 static int sandbox_mbox_bind(struct udevice *dev) 70 { 71 debug("%s(dev=%p)\n", __func__, dev); 72 73 return 0; 74 } 75 76 static int sandbox_mbox_probe(struct udevice *dev) 77 { 78 debug("%s(dev=%p)\n", __func__, dev); 79 80 return 0; 81 } 82 83 static const struct udevice_id sandbox_mbox_ids[] = { 84 { .compatible = "sandbox,mbox" }, 85 { } 86 }; 87 88 struct 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 95 U_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
