Since we don't currently create these, changes to fw_base.ldS do not
cause the preprocessed fw_*.elf.ld files to be rebuilt, and thus
incremental builds can end up failing with missing symbols if crossing
the recent commits that introduced _fw_rw_offset and then replaced it
with _fw_rw_start.
Reported-by: Ben Dooks <ben.dooks@sifive.com>
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
It seems BFD just does totally nonsensical things for SHN_ABS symbols
when producing position-independent outputs (both -pie and -shared)
for various historical reasons, and so SHN_ABS symbols are still
subject to relocation as far as BFD is concerned (except AArch64,
which fixes it in limited cases that don’t apply here...).
The above affects the _fw_rw_offset provided through fw_base.ldS
linker script which results in OpenSBI firmware failing to boot
when loaded at an address different from FW_TEXT_START.
Fixes: c10e3fe5f9 ("firmware: Add RW section offset in scratch")
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reported-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Tested-by: Anup Patel <apatel@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
BUG and BUG_ON are not informative and are rather lazy interfaces, only
telling the user that something went wrong in a given function, but not
what, requiring the user to find the sources corresponding to their
firmware (which may not be available) and figure out how that BUG(_ON)
was hit. Even SBI_ASSERT in its current form, which does include the
condition that triggered it in the output, isn't necessarily very
informative. In some cases, the error may be fixable by the user, but
they need to know the problem in order to have any hope of fixing it.
It's also a nuisance for developers, whose development trees may have
changed significantly since the release in question being used, and so
line numbers can make it harder for them to understand which error case
a user has hit.
This patch introduces a new sbi_panic function which is printf-like,
allowing detailed error messages to be printed to the console. BUG and
BUG_ON are removed, since the former is just a worse form of sbi_panic
and the latter is a worse version of SBI_ASSERT. Finally, SBI_ASSERT is
augmented to take a set of arguments to pass to sbi_panic on failure,
used like so (sbi_boot_print_hart's current error case, which currently
manually calls sbi_printf and sbi_hart_hang):
SBI_ASSERT(xlen >= 1, ("Error %d getting MISA XLEN\n", xlen));
The existing users of BUG are replaced with calls to sbi_panic along
with informative error messages. BUG_ON and SBI_ASSERT were unused (and,
in the case of SBI_ASSERT, remain unused).
Many existing users of sbi_hart_hang should be converted to use either
sbi_panic or SBI_ASSERT after this commit.
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
We only need libgcc for 64-bit division on RV32. Whilst GCC toolchains
bundle libgcc, Clang toolchains tend not to ship libclang_rt.builtins
given every compiler is a cross-compiler for every target and so you
would need a silly number of builds of it, with only the native library
available; only vendor-provided Clang toolchains specifically for bare
metal cross-compiling are likely to provide it.
Thus, import part of FreeBSD's implementation of the division support
functions needed and stop linking against libgcc.
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Anup Patel <anup.patel@wdc.com>
This is intended to mirror the Linux kernel. Building with CC=clang will
use Clang as the compiler but default to using the existing binutils.
Building with LLVM=1 will default to using Clang and LLVM binutils.
Whilst GCC will accept the -N linker option and forward it on to the
linker, Clang will not, and so in order to support both compilers we
must use -Wl, to forward it to the linker as is required for most other
linker options.
Note that there is currently a bug when using Clang as the compiler and
riscv64-linux-gnu-ld as the linker for FW_PIC=y. At first glance this
appears to be a bug in GNU binutils, but this could also be Clang or
OpenSBI at fault in some subtle way. Thus, for now, advise that this
combination be avoided.
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Anup Patel <anup.patel@wdc.com>
Bare-metal GNU ld does not support PIE, so if using it this will result
in a failure to build. Instead, default to FW_PIC=n if not supported.
Note that an explicit FW_PIC=y is not overridden, to ensure the build
fails rather than silently producing a position-dependent binary.
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
When using Clang with a bare-metal triple, -pie does not get passed to
the linker as it's not normally a thing that makes sense, unlike GCC
which will unconditionally forward it on and potentially result in a
linker error. However, LLD does support it, and manually forwarding it
on works as desired, so do so to fully support FW_PIC with Clang and
LLD.
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
The -N linker option is supposed to make .text writable, but GNU ld and
LLD differ in interpreting what that means. GNU ld will happily let you
have relocations in it, but LLD will see that the input section is
read-only (even though the output section is writable) and give an
error. It's unclear if either of them intend to have that behaviour in
this edge case, but regardless there's no reason not to just put the
data in a writable .data section.
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
These are mutually exclusive. GNU as and LLVM both let later binding
directives override earlier ones so this works as intended, but LLVM 12
turned this into a warning as there's no good reason to do such a thing
and could be a potential bug. Thus, remove the redundant and incorrect
.globl directive for fw_platform_init.
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
