diff options
| author | Philipp Hug <philipp@hug.cx> | 2018-07-07 15:54:37 +0200 |
|---|---|---|
| committer | Ronald G. Minnich <rminnich@gmail.com> | 2018-09-14 14:33:09 +0000 |
| commit | 2326a284ac6a6646a918331425952ece2da723c1 (patch) | |
| tree | d83f6fc80597a33132895edd356171547c753343 /util | |
| parent | 2912e8e5dc66708703db79df87e3215408a653ae (diff) | |
riscv: add trampoline in MBR block to support boot mode 1
Add "j pc + 0x0800" at the beginning of the MBR to jump to bootblock.
Tested on hardware:
boot mode 15: works as before
boot mode 1: jump to bootblock works, but bootblock needs to be modified to
move the stack to L2LIM. This will be in a separate commit.
Further changes are needed in the bootblock
Change-Id: I16e762d9f027346b124412f1f7ee6ff37f431d86
Signed-off-by: Philipp Hug <philipp@hug.cx>
Reviewed-on: https://review.coreboot.org/27397
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Diffstat (limited to 'util')
| -rwxr-xr-x | util/riscv/sifive-gpt.py | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/util/riscv/sifive-gpt.py b/util/riscv/sifive-gpt.py index cb77302528..fd82997fc6 100755 --- a/util/riscv/sifive-gpt.py +++ b/util/riscv/sifive-gpt.py @@ -25,6 +25,12 @@ BLOCK_MASK = BLOCK_SIZE - 1 # Size of the bootcode part of the MBR MBR_BOOTCODE_SIZE = 0x1be +# MBR trampoline to bootblock +MBR_BOOTCODE = bytes([ + # j pc + 0x0800 + 0x6f, 0x00, 0x10, 0x00, +]) + # A protecive MBR, without the bootcode part PROTECTIVE_MBR_FOOTER = bytes([ 0x00, 0x00, 0x02, 0x00, 0xee, 0xff, 0xff, 0xff, @@ -43,7 +49,7 @@ PROTECTIVE_MBR_FOOTER = bytes([ # [1]: https://en.wikipedia.org/wiki/GUID_Partition_Table#PROTECTIVE-MBR class ProtectiveMBR: def __init__(self): - self.bootcode = bytes(MBR_BOOTCODE_SIZE) + self.bootcode = MBR_BOOTCODE + bytes(MBR_BOOTCODE_SIZE - len(MBR_BOOTCODE)) def generate(self, stream): assert len(self.bootcode) == MBR_BOOTCODE_SIZE @@ -177,5 +183,11 @@ if __name__ == '__main__': image.fixup() + # Verify if first partition is at expected lba, otherwise trampoline will + # fail + if image.partitions[0].first_lba != 4: + print('Warning: First partition not at expected location (LBA 4)') + sys.exit(1) + with open(sys.argv[2], 'wb') as f: image.generate(f) |