Unless you have a spare Apple Silicon machine, getting access to
the serial port on Apple Silicon machines requires special
hardware. Given that most machines come with a built-in screen
the framebuffer is likely to be the most convenient output device
for most users. While U-Boot will output to both serial and
framebuffer, OSes might not. Therefore set stdout-path to point
at /chosen/framebuffer when a keyboard is connected to the machine.
This behaviour can be overridden by setting the "stdout" variable
in the U-Boot environment. I addition to that keep the serial
console as the default when running under the m1n1 hypervisor.
The m1n1 hypervisor virtualizes the serial port such that it
can be easily accessed from any other machine with a USB port.
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Janne Grunau <j@jannau.net>
Tested-by: Janne Grunau <j@jannau.net>
The M1 Ultra consists of two M1 Max dies. The second die's I/O is at
a consistent offset of 0x2000000000.
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Mark Kettenis <kettenis@openbsd.org>
The current approach for setting the environment variables that
describe the memory layout runs the risk of overlapping with
reserved memory regions. Use the lmb code to derive the addresses
for these variables instead.
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Support for Apple M1 Pro and Max will allow using a single binary for
all M1 SoCs. The M1 Pro/Max have a different memory layout. The RAM
start address is 0x100_0000_0000 instead of 0x8_0000_0000.
Replace the hardcoded memory layout with dynamic initialized
environment variables in board_late_init().
Tested on Mac Mini (2020) and Macbook Pro 14-inch (2021).
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Mark Kettenis <kettenis@openbsd.org>
Choose the memory map based on the compatible property from the
device tree passed to us by m1n1. Since DRAM on the M1 Pro/Max
starts at a different address avoid hardcoding the top of usable
memory. Also make sure that the addresses entered into the memory
map are page aligned such that we don't crash in dcache_enable().
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Tested on: Macbook M1 Max
Tested-by: Janne Grunau <j@jannau.net>
Rely on the new watchdog timer driver and the sysreset uclass to
reset the system. This gets rid of hard-coded addresses and
should work on systems based on the new M1 Pro and M1 Max SoCs
as well.
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-on: Apple M1 Macbook
Tested-by: Simon Glass <sjg@chromium.org>
Add support for Apple's M1 SoC that is used in "Apple Silicon"
Macs. This builds a basic U-Boot that can be used as a payload
for the m1n1 boot loader being developed by the Asahi Linux
project.
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
[trini: Add MAINTAINERS entry]
