1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Raspberry Pi 4 firmware reset driver
4  *
5  * Copyright (C) 2020 Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
6  */
7 #include <common.h>
8 #include <dm.h>
9 #include <reset-uclass.h>
10 #include <asm/arch/msg.h>
11 #include <dt-bindings/reset/raspberrypi,firmware-reset.h>
12 
raspberrypi_reset_request(struct reset_ctl * reset_ctl)13 static int raspberrypi_reset_request(struct reset_ctl *reset_ctl)
14 {
15 	if (reset_ctl->id >= RASPBERRYPI_FIRMWARE_RESET_NUM_IDS)
16 		return -EINVAL;
17 
18 	return 0;
19 }
20 
raspberrypi_reset_free(struct reset_ctl * reset_ctl)21 static int raspberrypi_reset_free(struct reset_ctl *reset_ctl)
22 {
23 	return 0;
24 }
25 
raspberrypi_reset_assert(struct reset_ctl * reset_ctl)26 static int raspberrypi_reset_assert(struct reset_ctl *reset_ctl)
27 {
28 	switch (reset_ctl->id) {
29 	case RASPBERRYPI_FIRMWARE_RESET_ID_USB:
30 		bcm2711_notify_vl805_reset();
31 		return 0;
32 	default:
33 		return -EINVAL;
34 	}
35 }
36 
raspberrypi_reset_deassert(struct reset_ctl * reset_ctl)37 static int raspberrypi_reset_deassert(struct reset_ctl *reset_ctl)
38 {
39 	return 0;
40 }
41 
42 struct reset_ops raspberrypi_reset_ops = {
43 	.request = raspberrypi_reset_request,
44 	.rfree = raspberrypi_reset_free,
45 	.rst_assert = raspberrypi_reset_assert,
46 	.rst_deassert = raspberrypi_reset_deassert,
47 };
48 
49 static const struct udevice_id raspberrypi_reset_ids[] = {
50 	{ .compatible = "raspberrypi,firmware-reset" },
51 	{ }
52 };
53 
54 U_BOOT_DRIVER(raspberrypi_reset) = {
55 	.name = "raspberrypi-reset",
56 	.id = UCLASS_RESET,
57 	.of_match = raspberrypi_reset_ids,
58 	.ops = &raspberrypi_reset_ops,
59 };
60 
61