Pin lists and mux values were taken from the Linux drivers.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
This is now handled automatically by the pinctrl driver.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Pin lists and mux values were taken from the Linux drivers.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
This is now handled automatically by the pinctrl driver.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Pin lists and mux values were taken from the Linux drivers.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
This includes UART0 and R_UART (s_uart) on all supported platforms, plus
the additional UART configurations from arch/arm/mach-sunxi/board.c.
Pin lists and mux values were taken from the Linux drivers.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
The sunxi pinctrl hardware has bias and drive control. Add driver
support for configuring those options.
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
The pinmux command uses this function to display pinmux status.
Since the driver cannot map pin numbers to a list of supported
functions, only functions which are common across all pins can be
reported by name.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Implement the operations to get pin and function names, and to set the
mux for a pin. The pin count and pin names are calculated as if each
bank has the maximum number of pins. Function names are simply the index
into a list of { function name, mux value } pairs.
We assume all pins associated with a function use the same mux value for
that function. This is generally true within a group of pins on a single
port, but generally false when some peripheral can be muxed to multiple
ports. For example, A64 UART3 uses mux 3 on port D, and mux 2 on port H.
But all of the port D pins use the same mux value, and so do all of the
port H pins. This applies even when the pins for some function are not
contiguous, and when the lower-numbered mux values are unused. A good
example of both of these cases is SPI0 on most SoCs.
This strategy saves a lot of space (which is especially important for
SPL), but where the mux value for a certain function differs across
ports, it forces us to choose a single port for that function at build
time. Since almost all boards use the default (i.e. reference design)
pin muxes[1], this is unlikely to be a problem.
[1]: See commit dda9fa734f ("sunxi: Simplify MMC pinmux selection")
Signed-off-by: Samuel Holland <samuel@sholland.org>
[Andre: add comment summarising the commit message]
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Create a do-nothing driver for each sunxi pin controller variant.
Since only one driver can automatically bind to a DT node, since the
GPIO driver already requires a manual binding process, and since the
pinctrl driver needs access to some of the same information, refactor
the GPIO driver to be bound by the pinctrl driver. This commit should
cause no functional change.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
U-boot is intended to replace linux kernel in android boot image(ABL), and
it's FIT payload to replace initramfs file. The boot process is similar to
boot image with linux:
- android bootloader (ABL) unpacks android boot image
- ABL sets `linux,initrd-start property` in chosen node in unpacked FDT
- ABL sets x0 register to FDT address, and passes control to u-boot
- u-boot reads x0 register, and stores it in `prevbl_fdt_addr` env variable
- u-boot reads `linux,initrd-start` property,
and stores it in `prevbl_initrd_start_addr`
In this way, u-boot bootcmd relies on `prevbl_initrd_start_addr` env
variable, and boils down to `bootm $prevbl_initrd_start_addr`.
If more control on boot process is desired, pack a boot script in
FIT image, and put it to default configuration
What done:
- strip unneeded config options
- add FIT image support
- add framebuffer node, u-boot logo and video console
- increase LMB_MAX_REGIONS, to store all linux dtb reserved memory regions
- add linux kernel image header
Uart driver causes hang, when u-boot is used in android boot image instead
of linux. Temporary disable console driver, until investigated and fixed.
Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
Cc: Ramon Fried <rfried.dev@gmail.com>
When u-boot is used as a chain-loaded bootloader (replacing OS kernel),
previous bootloader leaves data in RAM, that can be reused.
For example, on recent arm linux system, when chainloading u-boot,
there are initramfs and fdt in RAM prepared for OS booting. Initramfs
may be modified to store u-boot's payload, thus providing the ability to
use chainloaded u-boot to boot OS without any storage support.
Two config options added:
- SAVE_PREV_BL_INITRAMFS_START_ADDR
saves initramfs start address to 'prevbl_initrd_start_addr' environment
variable
- SAVE_PREV_BL_FDT_ADDR
saves fdt address to 'prevbl_fdt_addr' environment variable
Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
Cc: Tom Rini <trini@konsulko.com>
We already support the NVMe commands and PCIe backend in the QEMU target,
so let's make it easy for anyone to consume them and enable NVMe distro
boot along the way!
With this patch, I can put an NVMe backed disk image into my QEMU VM and
have it automatically load a UEFI target blob.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Mark Kettenis <kettenis@openbsd.org>
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Merge tag 'u-boot-at91-2022.07-a' of https://source.denx.de/u-boot/custodians/u-boot-at91 into next
First set of u-boot-at91 features for the 2022.07 cycle:
This feature set includes the new driver for the Atmel TCB timer,
alignment in DT for sama7g5 and sama7g5ek board, one Kconfig conversion
for external reset, and the usage of Galois tables from ROM for sama5d2
device.
If include/generated/env.in does not exist, which is a typical case for
clean build, quiet_cmd_gen_envp command tries to delete this file
unconditionally.
This produces following warning during the build:
ENVP include/generated/env.in
rm: cannot remove 'include/generated/env.in': No such file or directory
Add '-f' option to the `rm` command to not complain if file does not
exist.
Fixes: f432eb6d8a ("env: Avoid using a leftover text-environment file")
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com>
Unfortunately, we require additional logic to buildman to support this
removal and still use SYS_SOC, etc, for build targets.
This reverts commit eeec00072d.
Signed-off-by: Tom Rini <trini@konsulko.com>
This brings in two related series. The first from Andre:
This series is the continuation of last year's effort to support the new
Armv8-R64 application profile. This led to a significant rework of the
existing fastmodel (FVP) support, to both upgrade it to newest U-Boot
standards (OF_CONTROL and distro_boot support), but also to generalise
the code, so that plugging in the v8-R64 support in the last patch gets
much easier. This is because apart from the twisted memory map between
the two profiles there is actually little difference, when it comes to
U-Boot relevant parts of the hardware.
I kept the legacy semihosting support (which picks up magic files from
the current directory), but if that fails, we go and try virtio-blk
(.iso installer images work), then virtio-net.
Please have a look, and give it a try, if possible. Both the v8-R and
v8-A FVP models are available for free on the Arm website[1].
Patch 01/11 fixes a regression introduced in December, it should be
applied now. The rest of the patches are for the next merge window.
[1]
https://developer.arm.com/tools-and-software/simulation-models/fast-models
And the second from Sean (where we exclude 27, 28 and 29 for now):
This cleans up the semihosting code and adds the following new features:
- hostfs support (like sandbox)
- support for being used as a SPL boot device
- serial device support
- falling back to normal drivers if semihosting is disabled
The main device affected by these changes is vexpress64, so I'd
appreciate
if Andre (or anyone else) could try booting.
These changes are motivated by bringup for ls1046a. When forcing JTAG
boot, this device disables most communication peripherals, including
serial and ethernet devices. This appears to be fixed in later
generation devices, but we are stuck with it for now. Semihosting
provides an easy way to run a few console commands.
The patches in this series are organized as follows:
0-4: rST conversions and other documentation updates
5-9: Semihosting cleanups
10-14: Filesystem support (including SPL boot device)
15-16: Serial support
16: Documentation update
17: JTAG boot support for LS1046A
19-25: Semihosting fallback
26-29: DM puts support
The last two groups of patches are "bonus;" the first 17 patches stand
on their own. The last two groups could be broken out as separate
series, but I have kept them in this one to help with my sanity (and not
have to deal with too many outstanding series).
Patch 14 depends on [1] to apply cleanly. Patch 17 depends on [2] for
correctness. This series should be applied to u-boot/next (in
particular, the EROFS series must have been applied).
[1]
https://lore.kernel.org/u-boot/CACRpkdZ+9fmNjC_mvrbPa9-iuTQVd8UkJ7Zpe7cL0c5vZygsVw@mail.gmail.com/T/
[2]
https://lore.kernel.org/u-boot/20220222183840.1355337-2-sean.anderson@seco.com/
Some serial drivers can be vastly more efficient when printing multiple
characters at once. Non-DM serial has had a puts option for these sorts
of drivers; implement it for DM serial as well.
Because we have to add carriage returns, we can't just pass the whole
string directly to the serial driver. Instead, we print up to the
newline, then print a carriage return, and then continue on. This is
less efficient, but it is better than printing each character
individually. It also avoids having to allocate memory just to add a few
characters.
Drivers may perform short writes (such as filling a FIFO) and return the
number of characters written in len. We loop over them in the same way
that _serial_putc loops over putc.
This results in around sizeof(void *) growth for all boards with
DM_SERIAL. The full implementation takes around 140 bytes.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Use the semihosting_enabled function to determine whether or not to
enable semihosting devices. This allows for graceful fallback in the
event a debugger is not attached.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
If semihosting is disabled, then the user has no debugger attached, and
will not see any messages. Don't create a serial device in this
instance, to (hopefully) fall back on another working serial device.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
If a debugger is not attached to U-Boot, semihosting calls will raise a
synchronous abort exception. Try to catch this and disable semihosting
so we can e.g. use another uart if one is available. In the immediate
case, we return an error, since it is not always possible to check for
semihosting beforehand (debug uart, user-initiated load command, etc.)
We handle all possible semihosting instructions, which is probably
overkill. However, we do need to keep track of what instruction set
we're using so that we don't suppress an actual error.
A future enhancement could try to determine semihosting capability by
inspecting the processor state. There's an example of this at [1] for
RISC-V. The equivalent for ARM would inspect the monitor modei
enable/select bits of the DSCR. However, as the article notes, an
exception handler is still helpful in order to catch disconnected
debuggers.
[1] https://tomverbeure.github.io/2021/12/30/Semihosting-on-RISCV.html#avoiding-hangs-when-a-debugger-is-not-connected
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
These functions are intended to support detecting semihosting and
falling back gracefully to alternative implementations. The test starts
by making semihosting call. SYS_ERRNO is chosen because it should not
mutate any state. If this semihosting call results in an exception
(rather than being caught by the debugger), then the exception handler
should call disable_semihosting() and resume execution after the call.
Ideally, this would just be part of semihosting by default, and not a
separate config. However, to reduce space ARM SPL doesn't include
exception vectors by default. This means we can't detect if a
semihosting call failed unless we enable them. To avoid forcing them to
be enabled, we use a separate config option. It might also be possible
to try and detect whether a debugger has enabled (by reading HDE from
DSCR), but I wasn't able to figure out a way to do this from all ELs.
This patch just introduces the generic code to handle detection. The
next patch will implement it for arm64 (but not arm32).
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This imports some defines for esr and spsr from Linux v5.16. I have
modified the includes and fixed some indentation nits but otherwise it
is the same. There are a lot more defines than we need, but it doesn't
hurt.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This register holds "pstate" which includes (among other things) the
instruction mode the CPU was in when the exception was taken. This is
necessary to correctly interpret instructions at elr.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
To avoid passing around an extra register everywhere, save esr in
pt_regs like the rest. For proper alignment we need to have a second
(unused) register. All the printfs have to be adjusted, since
it's now an unsigned long and not an int.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This adds support for booting entirely from JTAG while using a
hard-coded RCW. With these steps, it is not necessary to program a
"good" RCW using CodeWarrior. The method here can be performed with any
JTAG adapter supported by OpenOCD, including the on-board CMSIS-DAP
(albeit very slowly).
These steps require LS1046A support in OpenOCD, which was added in [1].
[1] 5b70c1f679/
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
[trini: Add reference to doc/board/nxp/ls1046ardb.rst]
This documents how to use semihosting, the new semihosting features, and
how to migrate from smhload.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This adds a serial driver which uses semihosting calls to read and write
to the host's console. For convenience, if CONFIG_DM_SERIAL is enabled,
we will instantiate a serial driver. This allows users to enable this
driver (which has no physical device) without modifying their device
trees or board files. We also implement a non-DM driver for SPL, or for
much faster output in U-Boot proper.
There are three ways to print to the console:
Method Baud
================== =====
smh_putc in a loop 170
smh_puts 1600
smh_write with :tt 20000
================== =====
These speeds were measured using a 175 character message with a J-Link
adapter. For reference, U-Boot typically prints around 2700 characters
during boot on this board. There are two major factors affecting the
speed of these functions. First, each breakpoint incurs a delay. Second,
each debugger memory transaction incurs a delay. smh_putc has a
breakpoint and memory transaction for every character. smh_puts has one
breakpoint, but still has to use a transaction for every character. This
is because we don't know the length up front, so OpenOCD has to check if
each character is nul. smh_write has only one breakpoint and one memory
transfer.
DM serial drivers can only implement a putc interface, so we are stuck
with the slowest API. Non-DM drivers can implement puts, which is vastly
more efficient. When the driver starts up, we try to open :tt. Since
this is an extension, this may fail. If it does, we fall back to
smh_puts. We don't check :semihosting-features, since there are
nonconforming implementations (OpenOCD) which don't implement it (but
*do* implement :tt).
Some semihosting implementations (QEMU) don't handle READC properly. To
work around this, we try to use open/read (much like for stdin) if
possible.
There is no non-blocking I/O available, so we don't implement pending.
This will cause __serial_tstc to always return true. If
CONFIG_SERIAL_RX_BUFFER is enabled, _serial_tstc will try and read
characters forever. To avoid this, we depend on this config being
disabled.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This adds three wrappers around the semihosting commands for reading and
writing to the host console. We use the more standard getc/putc/puts
names instead of readc/writec/write0 for familiarity.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This command's functionality is now completely implemented by the
standard fs load command. Convert the vexpress64 boot command (which is
the only user) and remove the implementation.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Most U-Boot command deal with start/size instead of start/end. Convert
the "fdt chosen" command to use these semantics as well. The only user
of this subcommand is vexpress, so convert the smhload command to use
this as well. We don't bother renaming the variable in vexpress64's
bootcommand, since it will be rewritten in the next commit.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This adds a filesystem which is backed by the host's filesystem. It is
modeled off of sandboxfs, which has very similar aims. Semihosting
doesn't support listing directories (except with SYS_SYSTEM), so neither
do we. it's possible to optimize a bit for the common case of reading a
whole file by omitting a call to smh_seek, but this is left as a future
optimization.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This adds a boot method for loading the next stage from the host. It is
mostly modeled off of spl_load_image_ext. I am not really sure why/how
spl_load_image_fat uses three different methods to load the image, but
the simple case seems to work OK for now.
To control the presence of this boot method, we add a config symbol.
While we're at it, we update the original semihosting config symbol.
I think semihosting has some advantages of other forms of JTAG boot.
Common other ways to boot from JTAG include:
- Implementing DDR initialization through JTAG (typically with dozens of
lines of TCL) and then loading U-Boot. The DDR initialization
typically uses hard-coded register writes, and is not easily adapted
to different boards. BOOT_DEVICE_SMH allows booting with SPL,
leveraging U-Boot's existing DDR initialization code. This is the
method used by NXP's CodeWarrior IDE on Layerscape processors (see
AN12270).
- Loading a bootloader into SDRAM, waiting for it to initialize DDR, and
then loading U-Boot. This is tricky, because the debugger must stop the
boot after the bootloader has completed its work. Trying to load
U-Boot too early can cause failure to boot. This is the method used by
Xilinx with its Zynq(MP) processors.
- Loading SPL with BOOT_DEVICE_RAM and breaking before SPL loads the
image to load U-Boot at the appropriate place. This can be a bit
tricky, because the load address is dependent on the header size. An
elf with symbols must also be used in order to stop at the appropriate
point. BOOT_DEVICE_SMH can be viewed as an extension of this process,
where SPL automatically stops and tells the host where to place the
image.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
In order to add filesystem support, we will need to be able to seek and
write files. Add the appropriate helper functions.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Instead of printing in what are now library functions, try to return a
numeric error code. This also adjust some functions (such as read) to
behave more similarly to read(2). For example, we now return the number
of bytes read instead of failing immediately on a short read.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
There's no point in using string constants for smh_open if we are just
going to have to parse them. Instead, use numeric modes. The user needs
to be a bit careful with these, since they are much closer semantically
to string modes used by fopen(3) than the numeric modes used with
open(2).
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This exports semihosting functions for use in other files. The header is
in include/ and not arm/include/asm because I anticipate that RISC-V may
want to add their own implementation at some point.
smh_len_fd has been renamed to smh_flen to more closely match the
semihosting spec.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
These files are spread all over the tree, so just use a regex. Orphaned
for now, since this is more of a "one-off" series. Though I'll be happy
to review patches.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This adds some instructions for enabling the debug uart, including the
correct address and clock rate.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This adds some additional info about booting from different sources,
including the correct switch positions.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This converts the readme for this board to rST. I have tried not to
change any semantics from the original (though I did convert MB to M).
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
This converts the semihosting readme to rST. I have tried to make only
cosmetic changes, but I did fix up the first link (which was broken).
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
The ARMv8-R64 architecture introduces optional VMSA (paging based MMU)
support in the EL1/0 translation regime, which makes that part mostly
compatible to ARMv8-A.
Add a new board variant to describe the "BASE-R64" FVP model, which
inherits a lot from the existing v8-A FVP support. One major difference
is that the memory map in "inverted": DRAM starts at 0x0, MMIO is at
2GB [1].
* Create new TARGET_VEXPRESS64_BASER_FVP target, sharing most of the
exising configuration.
* Implement inverted memory map in vexpress_aemv8.h
* Create vexpress_aemv8r defconfig
* Provide an MMU memory map for the BASER_FVP
* Update vexpress64 documentation
At the moment the boot-wrapper is the only supported secure firmware. As
there is no official DT for the board yet, we rely on it being supplied
by the boot-wrapper into U-Boot, so use OF_HAS_PRIOR_STAGE, and go with
a dummy DT for now.
[1] https://developer.arm.com/documentation/100964/1114/Base-Platform/Base---memory/BaseR-Platform-memory-map
Signed-off-by: Peter Hoyes <Peter.Hoyes@arm.com>
[Andre: rebase and add Linux kernel header]
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
[trini: Add MAINTAINERS entry for Peter]
So far the DRAM size for both the Juno and the FVP model were hardcoded
in our config header file. For the Juno this is fine, as all models have
8 GiB of DRAM, but the DRAM size can be configured on the model command
line.
Drop the fixed DRAM size setup, instead look up the size in the device
tree, that we now have for every board. This allows a user to inject
a DT with the proper size, and be able to use the full amount of DRAM.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
In preparation for the ARMv8-R64 FVP support, which has DRAM mapped at
0x0, generalise the page table generation, by using symbolic names for
the address ranges instead of fixed numbers.
We already define the base of the DRAM and MMIO regions, so just use
those symbols in the page table description. Rename V2M_BASE to the more
speaking V2M_DRAM_BASE on the way.
On the VExpress memory map, the address space right after 4GB is of no
particular interest to software, as the whole of DRAM is mapped at 32GB
instead. The first 2 GB alias to the lower 2GB of DRAM mapped below 4GB,
so we skip this part and map some more of the high DRAM, should anyone
need it.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Right now the defconfig the Arm VExpress64 boards disables quite some
standard commands, for apparently no good reasons (as image size is
hardly a concern here).
Remove the lines explicitly disabling those features, leaving it to
the U-Boot default settings to set them.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
So far the FVP model just supports booting through semihosting, so by
loading files from the host the model is running on. This allows for
quick booting of new kernels (or replacing DTBs), but prevents more
featureful boots like using UEFI.
Enable the distro_boot feature, and provide a list of possible boot
sources that U-Boot should check:
- For backwards compatibility we start with semihosting, which gets its
commands migrated from CONFIG_BOOTCOMMAND into the distro_boot
infrastructure. This is also slightly tweaked to fail graceful in case
the required files could not be found.
- Next we try to use a user provided script, that could be easily
placed into memory using the model command line.
- Since we gained virtio support with the enablement of OF_CONTROL,
let's check virtio block devices next. This is where UEFI boot can
be easily used, for instance by providing a distro installer .iso
file through virtio-blk.
- Networking is now provided by virtio as well, so enable the default
PXE and DHCP boot flows, mostly because we can.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
