linux/arch/riscv/Kconfig.erratas
Vincent Chen 800149a77c
riscv: sifive: Apply errata "cip-453" patch
Add sign extension to the $badaddr before addressing the instruction page
fault and instruction access fault to workaround the issue "cip-453".

To avoid affecting the existing code sequence, this patch will creates two
trampolines to add sign extension to the $badaddr. By the "alternative"
mechanism, these two trampolines will replace the original exception
handler of instruction page fault and instruction access fault in the
excp_vect_table. In this case, only the specific SiFive CPU core jumps to
the do_page_fault and do_trap_insn_fault through these two trampolines.
Other CPUs are not affected.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26 08:24:57 -07:00

34 lines
1018 B
Plaintext

menu "CPU errata selection"
config RISCV_ERRATA_ALTERNATIVE
bool "RISC-V alternative scheme"
default y
help
This Kconfig allows the kernel to automatically patch the
errata required by the execution platform at run time. The
code patching is performed once in the boot stages. It means
that the overhead from this mechanism is just taken once.
config ERRATA_SIFIVE
bool "SiFive errata"
depends on RISCV_ERRATA_ALTERNATIVE
help
All SiFive errata Kconfig depend on this Kconfig. Disabling
this Kconfig will disable all SiFive errata. Please say "Y"
here if your platform uses SiFive CPU cores.
Otherwise, please say "N" here to avoid unnecessary overhead.
config ERRATA_SIFIVE_CIP_453
bool "Apply SiFive errata CIP-453"
depends on ERRATA_SIFIVE
default y
help
This will apply the SiFive CIP-453 errata to add sign extension
to the $badaddr when exception type is instruction page fault
and instruction access fault.
If you don't know what to do here, say "Y".
endmenu