diff options
| author | Lukas Auer <lukas.auer@aisec.fraunhofer.de> | 2019-08-13 00:50:42 +0300 |
|---|---|---|
| committer | Anup Patel <anup.patel@wdc.com> | 2019-08-13 06:37:16 +0300 |
| commit | 2e0f3ac758da99fb6d1b4c651643999d83cd0a7f (patch) | |
| tree | 469e7b7c43d8d3c32e03642a6b4df6894fe8aace /firmware | |
| parent | 6c24193293e7cc0854994d7551f32e31ebc06ff6 (diff) | |
| download | opensbi-2e0f3ac758da99fb6d1b4c651643999d83cd0a7f.tar.xz | |
firmware: do not use relocated _boot_status before it is valid
When OpenSBI is started from an address not equal to the link address,
it is first relocated to the link address. Hart 0 performs the
relocation and notifies the other harts of its completion with the
_boot_status variable. It uses the copy of the variable relative to the
link address. This copy contains valid data only after relocation has
finished. The waiting harts will therefore read invalid data until
relocation has finished. This can cause them to continue execution too
early.
Fix this by using the _boot_status variable relative to the load address
while OpenSBI has not finished relocation.
Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Diffstat (limited to 'firmware')
| -rw-r--r-- | firmware/fw_base.S | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/firmware/fw_base.S b/firmware/fw_base.S index f2b1ee0..f596638 100644 --- a/firmware/fw_base.S +++ b/firmware/fw_base.S @@ -111,8 +111,6 @@ _wait_relocate_copy_done: REG_L t1, 0(t1) beq t0, t1, _wait_for_boot_hart la t2, _boot_status - sub t2, t2, t0 - add t2, t2, t1 la t3, _wait_for_boot_hart sub t3, t3, t0 add t3, t3, t1 @@ -128,8 +126,17 @@ _wait_relocate_copy_done: jr t3 _relocate_done: - /* mark relocate copy done */ + /* + * Mark relocate copy done + * Use _boot_status copy relative to the load address + */ la t0, _boot_status + la t1, _link_start + REG_L t1, 0(t1) + la t2, _load_start + REG_L t2, 0(t2) + sub t0, t0, t1 + add t0, t0, t2 li t1, BOOT_STATUS_RELOCATE_DONE REG_S t1, 0(t0) fence rw, rw |