[coreboot-gerrit] [M] Change in coreboot[main]: riscv/mb/qemu: fix DRAM probing

[Philipp Hug (Code Review)]

Attention is currently required from: Arthur Heymans, Arthur Heymans, Maximilian Brune, ron minnich, ron minnich.

Hello Arthur Heymans, Marc Karasek, Martin L Roth, Maximilian Brune, build bot (Jenkins), ron minnich,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/36486?usp=email

to look at the new patch set (#14).

Change subject: riscv/mb/qemu: fix DRAM probing
......................................................................

riscv/mb/qemu: fix DRAM probing

Current version of qemu raise an exception when accessing invalid memory.
Modify the probing code to temporary redirect the exception handler like on
ARM platform.
Also move saving of the stack frame out to trap_util.S to have all at the same
place for a future rewrite.

TEST=boots to ramstage
Change-Id: I25860f688c7546714f6fdbce8c8f96da6400813c
Signed-off-by: Philipp Hug 
Signed-off-by: Arthur Heymans 
---
M src/arch/riscv/Makefile.mk
M src/arch/riscv/include/arch/exception.h
A src/arch/riscv/ramdetect.c
M src/arch/riscv/trap_handler.c
M src/arch/riscv/trap_util.S
M src/lib/imd_cbmem.c
6 files changed, 93 insertions(+), 19 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/86/36486/14