On the raspberry pi, you can disable the serial port to gain dynamic frequency
scaling which can get handy at times.
However, in such a configuration the serial controller gets its rx queue filled
up with zero bytes which then happily get transmitted on to whoever calls
getc() today.
This patch adds detection logic for that case by checking whether the RX pin is
mapped to GPIO15 and disables the mini uart if it is not mapped properly.
That way we can leave the driver enabled in the tree and can determine during
runtime whether serial is usable or not, having a single binary that allows for
uart and non-uart operation.
Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Introduce virtual and physical addresses in the mapping table. This change
have no impact on existing boards because they all use idential mapping.
Signed-off-by: York Sun <york.sun@nxp.com>
On all Pis so far, the VC FW provides a short stub to set up the ARM CPU
before entering the kernel (a/k/a U-Boot for us). This feature is not
currently supported by the VC FW when booting in 64-bit mode. However,
this feature will likely appear in the near future, and this U-Boot port
assumes that such a feature is in place. Without that feature, or a
temporary workaround described below, U-Boot will not boot.
Once the VC FW does provide the ARM stub, u-boot.bin built for rpi_3 can
be used drectly as kernel7.img, in the same way as any other RPi port. The
following config.txt is required:
# Fix mini UART input frequency, and setup/enable up the UART.
# Without this option, U-Boot will not boot, even if you don't care
# about the serial console. This option will always be required for
# all RPi3 use-cases, unless the PL011 UART is used, which is not
# yet supported by rpi_3* builds of U-Boot.
enable_uart=1
# Boot in AArch64 (64-bit) mode.
# It is possible that a future VC FW will remove the need for this
# option, instead auto-setting 32-/64-bit mode based on the "kernel"
# filename present on the SD card.
arm_control=0x200
Prior to the VC FW providing the ARM boot stub, you can use the following
steps to build an equivalent stub into the U-Boot binary:
git clone https://github.com/swarren/rpi-3-aarch64-demo.git \
../rpi-3-aarch64-demo
(cd ../rpi-3-aarch64-demo && ./build.sh)
Build U-Boot for rpi_3 in the usual way
cat ../rpi-3-aarch64-demo/armstub64.bin u-boot.bin > u-boot.bin.stubbed
Use u-boot.bin.stubbed as kernel7.img on the Pi SD card.
In this case, the following additional entries are required in config.txt:
# Tell the FW to load the kernel image at address 0, the reset vector.
kernel_old=1
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
The Raspberry Pi 3 contains a BCM2837 SoC. The BCM2837 is a BCM2836 with
the CPU complex swapped out for a quad-core ARMv8. This can operate in 32-
or 64-bit mode. 32-bit mode is the current default selected by the
VideoCore firmware on the Raspberry Pi 3. This patch adds a 32-bit port of
U-Boot for the Raspberry Pi 3.
>From U-Boot's perspective, the only delta between the RPi 2 and RPi 3 is a
change in usage of the SoC UARTs. On all previous Pis, the PL011 was the
only UART in use. The Raspberry Pi 3 adds a Bluetooth module which uses a
UART to connect to the SoC. By default, the PL011 is used for this purpose
since it has larger FIFOs than the other "mini" UART. However, this can
be configured via the VideoCore firmware's config.txt file. This patch
hard-codes use of the mini UART in the RPi 3 port. If your system uses the
PL011 UART for the console even on the RPi 3, please use the RPi 2 U-Boot
port instead. A future change might determine which UART to use at
run-time, thus allowing the RPi 2 and RPi 3 (32-bit) ports to be squashed
together.
The mini UART has some limitations. One externally visible issue in the
BCM2837 integration is that the UART divides the SoC's "core clock" to
generate the baud rate. The core clock is typically variable, and under
control of the VideoCore firmware for thermal management reasons. If the
VC FW does modify the core clock rate, UART communication will be
corrupted since the baud rate will vary from the expected value. This was
not an issue for the PL011 UART, since it is fed by a fixed 3MHz clock. To
work around this, the VideoCore firmware can be told not to modify the SoC
core clock. However, the only way this can happen and be thermally safe is
to limit the core clock to a low/minimum frequency. This leaves
performance on the table for use-cases that don't care about a UART
console. Consequently, use of the mini UART console must be explicitly
requested by entering the following line into config.txt:
enable_uart=1
A recent version of the VC firmware is required to ensure that the mini
UART is fully and correctly initialized by the VC FW; at least
firmware.git 046effa13ebc "firmware: arm_loader: emmc clock depends on
core clock See: https://github.com/raspberrypi/firmware/issues/572".
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
This allows U-Boot to known the name of the board.
The existing rpi_2_defconfig can operate correctly on the Raspberry Pi 3
in 32-bit mode /if/ you have configured the firmware to use the PL011 UART
as the console UART (the default is the mini UART). This requires two
things:
a) config.txt should contain dtoverlay=pi3-miniuart-bt
b) You should run the following to tell the VC FW to process DT when
booting, and copy u-boot.bin.img (rather than u-boot.bin) to the SD card
as the kernel image:
path/to/kernel/scripts/mkknlimg --dtok u-boot.bin u-boot.bin.img
This works as of firmware.git commit 046effa13ebc "firmware: arm_loader:
emmc clock depends on core clock See:
https://github.com/raspberrypi/firmware/issues/572".
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
To simplify support for new SoCs, just use a constant filename
for the unknown case. In practice this case shouldn't be hit anyway, so
the filename isn't relevant, and certainly doesn't need to differentiate
between SoCs. If a user has an as-yet-unknown board, they can override
this value in the environment anyway.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Currently, CONFIG_BCM2835 is defined for all BCM283x builds and _BCM2836
is defined when building for that SoC. That means there isn't a single
define that means "exactly BCM2835". This will complicate future patches
where BCM2835-vs-anything-else needs to be determined simply.
Modify the code to define one or the other of CONFIG_BCM2835/BCM2836 so
future patches are simpler.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
For Raspberry Pi, we had the input clock rate to the pl011 fixed in
the rpi.c file, but it may be changed by firmware due to user changes
to config.txt. Since the firmware always sets up the uart (default
115200 output unless the user changes it), we can just skip our own
uart init to simplify the boot process and more reliably get serial
output.
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Tom Rini <trini@konsulko.com>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Gets propagated into the device tree and then into /proc/cpuinfo where
users often expect it.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Stephen Warren <swarren@wwwdotorg.org>
Let's set "ethaddr" when we get the ethernet address too, so that
fdt_fixup_ethernet() sets the address in the device tree and the Linux
driver can pick it up.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
The P5 header was not present on "Model B" any board prior to Revision 2.0,
there's no need for a separate device tree.
Also, it looks like "rev2" is incorrectly used to only cover the 512MiB
memory models; there also were 256MiB 2.0 boards.
I don't have all of the boards to check this, I'm following this table:
http://elinux.org/RPi_HardwareHistory#Board_Revision_History
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
This source has been blessed by Dom Cobley at the RPi Foundation, so seems
like the best source to refer to. It's a superset of and consistent with
the other sources.
Cc: Lubomir Rintel <lkundrak@v3.sk>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
The RPi has two different schemes for encoding board revision values.
When adding RPi 2 support, I thought that the conflicting type field
values were to be interpreted based on bcm2835-vs-bcm2836. In fact, the
scheme bit determines the encoding. The RPi Zero uses the bcm2835 yet
uses the new encoding scheme. Fix the code to cater for this correctly.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
There are two numbering schemes for the RPi revision values; old and new
scheme. The values within each scheme overlap. Hence, it doesn't make
sense to have absolute/global names for the revision IDs. Get rid of the
names and just use the raw revision/type values to set up the array of
per-revision data.
This change makes most sense when coupled with the next change. However,
it's split out so that the mechanical cut/paste is separate from the
logic changes for easier review and problem bisection.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Add CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG support and enable it to set
'board_rev' and 'board_name' envs.
'board_rev' can be used in scripts to determine what board we are running on
and 'board_name' for pretty printing.
Signed-off-by: Guillaume GARDET <guillaume.gardet@free.fr>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Seen this one in the wild. Is labelled "Raspberry Pi Model A+ V1.1,
(C) Raspberry Pi 2014". A standard A+ board, much like the one with
version 0x12, didn't notice any differencies.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Now that we have a new header file for cache-aligned allocation, we should
move the stack-based allocation macro there also.
Signed-off-by: Simon Glass <sjg@chromium.org>
The mailbox buffer is required to be at least 16 bytes aligned, but for
cache invalidation and/or flush it needs to be cacheline aligned.
Use ALLOC_CACHE_ALIGN_BUFFER for all mailbox buffer allocations.
Signed-off-by: Alexander Stein <alexanders83@web.de>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Apparently the firmware's board rev response includes both the board
revision and some other data even on the RPi1. In particular, the
"warranty bit" is bit 24. We need to mask that out when looking up the
board ID.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
USB doesn't seem to work yet; the controller detects the on-board Hub/
Ethernet device but can't read the descriptors from it. I haven't
investigated yet.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
We now have api functions that can support compiling simplefb code as its own
module. Since this code is not part of the display functionality, extract it
to its own file.
Raspberry Pi is updated to accommodate the changes.
Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Bo Shen <voice.shen@atmel.com>
Tested-by: Josh Wu <josh.wu@atmel.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Create a fake model table entry with default values, so we can error
check the board rev value once when querying it from the firmware, rather
than error-checking for invalid board rev values every time the model
table is used.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Add a board rev entry for the new model A+, and augment the board
rev error handling code to be a bit more verbose.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Model A and CM RPis don't have an on-board USB Ethernet device. Hence,
there's no point setting $usbethaddr based on the device fuses. Use the
model detection code to gate this. Note that the fuses are actually
programmed even on those devices though.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Adjust the configuration to use the driver model version of the pl01x
serial driver. Add the required platform data.
Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
The U-Boot port runs on a variety of RPi models, not just the B. So,
rename the port to something slightly more generic.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
