This patch extends fw_base to relocate to link address whenever
firmware load address is not equal to link address.

The relocation will not work when load start to load end overlap
link start to link end.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>

The linker sections .sdata and .sbss are missing from the linker script
fw_base.ldS. Add them to the .data and .bss sections.

On current builds, most variables are in the .sbss section. They are not
correctly initialized to zero, because they are not within the
boundaries indicated by _bss_start and _bss_end. Currently, this does
not cause any issues, however with relocation support lock-ups may occur
due to incorrectly initialized lock variables.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Acked-by: Anup Patel <anup.patel@wdc.com>

Add Andreas Schwab to the contributors list.

Signed-off-by: Karsten Merker <merker@debian.org>
Acked-by: Andreas Schwab <schwab@suse.de>

- OpenSBI build target should be: qemu/sifive_u
- U-Boot config name should be: sifive_fu540_defconfig

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Since QEMU commit 8b1d0714bfdd
"riscv: sifive_u: Allow up to 4 CPUs to be created",
the maximum number of hart for sifive_u is 4.

Change our hart count to match that.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

The unpriv load/store instruction from M-mode can cause page/access
fault to M-mode if S-mode page table did not have mappings OR it did
not have PMP access permission.

To tackle this, we redirect trap back to S-mode if unpriv load/store
instruction traps in M-mode.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch adds per-HART trap info pointer which can be used to
communicate trap information to sbi_trap_handler().

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Currently, the unprivilege load/store functions are inline functions.

We will be extending these functions to track whether a page/access
fault occurs when we execute unprivilege load/store instruction.

To make things simpler and debugable, we reduce number of places which
can potentially generate a page/access fault by making all unprivilege
load/store functions as regular (non-inline) functions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch factor-out TLB management from IPI management to separate
sources sbi_tlb.c and sbi_tlb.h.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

We have extra space above scratch space (sbi_scratch) which we are
currently using to manage per-HART IPI data and TLB request management.

In future, more parts of OpenSBI will use the extra scratch space so
it will become difficult to manage extra scratch space using just
defines and macros.

This patch adds a simple brain-dead allocator to manage extra scratch
space. This allocator never expects anything to be free-ed hence it
keeps incrementing to next allocation offset until it runs-out of space.

In future, we can have more sophisticated allocator which will allow
us to re-claim free-ed space and also allows us to track owner of
allocated space.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

On latest Linux kernel (i.e. 5.2-rc1), we get large TLB flush
request for user space addresses (typically, start=x and end=-1).
This is caused by Linux kernel commit a21344dfc6 ("riscv: fix
sbi_remote_sfence_vma{,_asid}").

It's not practical to execute large number of sfence instructions
for a large TLB flush range because it takes too much time and
eventually causes CPU stall in Linux kernel.

This patch addresses above issue by upgrading TLB flush range to
TLB flush all whenever TLB flush range is greater than 1GB.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch adds documenation about dynamic firmware.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch enables FW_DYNAMIC option (i.e. dynamic firmware) for
all appropriate/applicable platforms.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

This patch provides first-cut implementation of fw_dynamic firmware.

As compared to fw_jump and fw_payload, the fw_dynamic obtains next
address, next mode and OpenSBI options from struct fw_dynamic_info.

The previous booting stage can create struct fw_dynamic_info in memory
and pass address of struct fw_dynamic_info in 'a2' register. Also, the
struct fw_dynamic_info has versioning as well so changes to the struct
fw_dynamic_info can be done in a backward compatible manner.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch extends existing firmwares (i.e. fw_jump and fw_payload)
to explicitly provide next mode and options to fw_base.

We also introduce fw_save_info() which is called by fw_base very
early on boot HART. This function can be used by existing firmwares
(i.e. fw_jump and fw_payload) to save information passed by previous
booting stage.

Overall, this is a preparatory patch for implementing fw_dynamic.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

OpenSBI has recently gained a CONTRIBUTORS.md file as a way
to make contributions to OpenSBI more visible.  Add previous
contributors from the git history who have acked their
inclusion in the list to the file.

Signed-off-by: Karsten Merker <merker@debian.org>
Acked-by: Alistair Francis <alistair@alistair23.me>
Acked-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Acked-by: Nick Kossifidis <mickflemm@gmail.com>
Acked-by: Shawn Chang <citypw@gmail.com>
Acked-by: Xiang Wang <wxjstz@126.com>

- fix some broken hyperlinks
- add additional hyperlinks to references to external documents
- reformat some paragraphs to keep lines under 80 characters
- unify the enumeration style between different parts of the
  documentation
- fix spelling/grammar mistakes
- extend the copyright notice in README.md to be the same as the
  one in COPYING.BSD

Signed-off-by: Karsten Merker <merker@debian.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Fix typo on parenthesis.

The various available RISC-V toolchains differ in their default
configuration regarding PIE, e.g. the buildroot RISC-V toolchain
has PIE disabled by default while the Debian toolchain has it
enabled by default.

OpenSBI currently doesn't support being built with PIE enabled,
therefore disable it explicitly by passing "-fno-pie -no-pie" in
CFLAGS.

Signed-off-by: Karsten Merker <merker@debian.org>
Acked-by: Anup Patel <anup.patel@wdc.com>

Signed-off-by: Xiang Wang <wxjstz@126.com>

Signed-off-by: Shawn Chang <citypw@gmail.com>

Noisy commit, no functional changes.

Generated with an current upstream clang-format and:

clang-format -i $(find . -name \*.[ch])

Signed-off-by: Olof Johansson <olof@lixom.net>

One of the shortcomings of clang-format is that it doesn't allow
for aligned define tables, which is used for a number of constants.

Add annotation to disable the automatic formatting where needed.

Signed-off-by: Olof Johansson <olof@lixom.net>

Add an empty clang-format to disable reformatting of imported code and
make it easier to merge in upstream changes of that project over time.

Signed-off-by: Olof Johansson <olof@lixom.net>

Add a clang-format to automate consistent code formatting.

Automating coding style reformatting removes a lot of manual
checkpatch-type fixups, and can easily be implemented as a linter in
code review environments.

Signed-off-by: Olof Johansson <olof@lixom.net>

In case we didn't handle a trap with one of the available
handlers, check if the trap comes from S or U mode and
redirect it to S mode's trap handler.

Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>

All dependant patches are merged in U-Boot and Linux kernel now.
Update the unleashed guide to reflect that and fix the documentation
about tftp loading path as well.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

We add CONTRIBUTORS.md file to provide a list of individuals and
organizations actively contributing to the OpenSBI project.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

- Correct the payload address in the RV64 examples that use
  fw_jump.elf.

- Change the qemu console configuration in the examples from
  "-display none -serial stdio" to "-nographic". This results in
  qemu handing down a CTRL-C on the emulated console to the VM
  instead of terminating the qemu process.

- Provide examples for RV32.

- Various text corrections.

Signed-off-by: Karsten Merker <merker@debian.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Simulatenous requests for tlbflush IPIs can have overlapping address
ranges.

Ignore if address range is same or within already existing fifo entries.
Update the tlb flush info in fifo directly if the one of the existing
entry lies within the new flush request.
Delete all entries if flush all request is recieved for the vma.

Signed-off-by: Atish Patra <atish.patra@wdc.com>

Implement a lock enabled iteration for fifo so that
caller can determine if next entry can be skipped or
any existing entries in fifo can be updated before enqueue.

Signed-off-by: Atish Patra <atish.patra@wdc.com>

This patch extends our current build-system for building platform
sources which are not part of OpenSBI sources.

For example:

Let's say we have out-of-tree ABC platform sources. We place these
sources under <XYZ>/ABC directory along with its config.mk and
objects.mk.

To build out-of-tree ABC platform from OpenSBI directory:
$ make PLATFORM_DIR=<XYZ>/ABC
OR
$ make PLATFORM_DIR=<XYZ> PLATFORM=ABC

To build out-of-tree ABC platform from <XYZ>/ABC directory:
$ make PLATFORM_DIR=<XYZ>/ABC -C <path_to_opensbi>
OR
$ make PLATFORM_DIR=<XYZ> PLATFORM=ABC -C <path_to_opensbi>

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Fix the ECALL definitions to matc the latest information in the
privlidge spec table 5.5.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

When I tried to start opensbi with coreboot, I found that aligning to a 16-byte
boundary would make a copy error.

Corrected to align to an machine word length boundary.

Signed-off-by: Xiang Wang <wxjstz@126.com>

This patch reduces memory consumed by struct sbi_fifo by droping
redundant "head" member and using u16 in-place of "unsigned long".

Signed-off-by: Anup Patel <anup.patel@wdc.com>

This patch does following improvements to sbi_fifo:
1. Use valid SBI_Exxxx error codes instead of -1
2. The sbi_fifo_is_full() and sbi_fifo_is_empty() did
   not acquire qlock before accessing head and tail
   hence fixed it
3. Added avail member for ease in debugging and simplifying
   head/tail updates.

Due to above changes size of sbi_fifo changes from 48 bytes
to 56 bytes.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

We now have an OpenSBI mailing list available for development
and discussiong so update contributing.md accordingly. The
Github PR based review and issue tracking will also continue
to exist.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

Currently, there is no provision for tracking multiple IPIs sent
to a single hart at the same time by different harts.

Use a fifo manage the outstanding requests. While dequeueing, read all
the entries once, because we have only 1 bit to track the type of IPI.
Once the queue is full, busy wait until the there is space available in
queue. This is not the most elegant approach. It should be changed in
favor of a wakeup event once available in opensbi.

Signed-off-by: Atish Patra <atish.patra@wdc.com>

Currently scratch space per hart is 256 bytes. Increase it to 512 bytes
to accomodate ipi queue.

Signed-off-by: Atish Patra <atish.patra@wdc.com>

Add a tlb info to distinguish between different type of tlb flush
request pending.

Signed-off-by: Atish Patra <atish.patra@wdc.com>