From f676eb217bdff3bd734a42c8f9bbc58c9100055c Mon Sep 17 00:00:00 2001 From: Nicolas Saenz Julienne Date: Mon, 29 Jun 2020 18:37:23 +0200 Subject: reset: Add Raspberry Pi 4 firmware reset controller Raspberry Pi 4's co-processor controls some of the board's HW initialization process, but it's up to Linux to trigger it when relevant. Introduce a reset controller capable of interfacing with RPi4's co-processor that models these firmware initialization routines as reset lines. Signed-off-by: Nicolas Saenz Julienne Signed-off-by: Matthias Brugger --- drivers/reset/reset-raspberrypi.c | 60 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 drivers/reset/reset-raspberrypi.c (limited to 'drivers/reset/reset-raspberrypi.c') diff --git a/drivers/reset/reset-raspberrypi.c b/drivers/reset/reset-raspberrypi.c new file mode 100644 index 0000000000..e2d284e5ac --- /dev/null +++ b/drivers/reset/reset-raspberrypi.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Raspberry Pi 4 firmware reset driver + * + * Copyright (C) 2020 Nicolas Saenz Julienne + */ +#include +#include +#include +#include +#include + +static int raspberrypi_reset_request(struct reset_ctl *reset_ctl) +{ + if (reset_ctl->id >= RASPBERRYPI_FIRMWARE_RESET_NUM_IDS) + return -EINVAL; + + return 0; +} + +static int raspberrypi_reset_free(struct reset_ctl *reset_ctl) +{ + return 0; +} + +static int raspberrypi_reset_assert(struct reset_ctl *reset_ctl) +{ + switch (reset_ctl->id) { + case RASPBERRYPI_FIRMWARE_RESET_ID_USB: + bcm2711_notify_vl805_reset(); + return 0; + default: + return -EINVAL; + } +} + +static int raspberrypi_reset_deassert(struct reset_ctl *reset_ctl) +{ + return 0; +} + +struct reset_ops raspberrypi_reset_ops = { + .request = raspberrypi_reset_request, + .rfree = raspberrypi_reset_free, + .rst_assert = raspberrypi_reset_assert, + .rst_deassert = raspberrypi_reset_deassert, +}; + +static const struct udevice_id raspberrypi_reset_ids[] = { + { .compatible = "raspberrypi,firmware-reset" }, + { } +}; + +U_BOOT_DRIVER(raspberrypi_reset) = { + .name = "raspberrypi-reset", + .id = UCLASS_RESET, + .of_match = raspberrypi_reset_ids, + .ops = &raspberrypi_reset_ops, +}; + -- cgit v1.2.3