56 Commits

Author SHA1 Message Date
Lukas Auer
31f9058994 riscv: do not blindly modify the mstatus CSR
The mstatus CSR includes WPRI (writes preserve values, reads ignore
values) fields and must therefore not be set to zero without preserving
these fields. It is not apparent why mstatus is set to zero here since
it is not required for U-Boot to run. Remove it.

This instruction and others encode zero as an immediate.  RISC-V has the
zero register for this purpose. Replace the immediates with the zero
register.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2018-11-26 13:57:32 +08:00
Lukas Auer
8bfa231cc6 riscv: remove unused labels in start.S
The labels nmi_vector, trap_vector and handle_reset in start.S are not
used for RISC-V. Remove them.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2018-11-26 13:57:32 +08:00
Bin Meng
c95cafd0b1 Drop CONFIG_INIT_CRITICAL
This is now deprecated and no board is using it. Drop it.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2018-11-26 13:57:31 +08:00
Lukas Auer
2a23ac6107 riscv: align mtvec on a 4-byte boundary
The machine trap-vector base address (mtvec) must be aligned on a 4-byte
boundary. Add the necessary align directive to trap_entry.

This patch also removes the global directive for trap_entry, which is
not required.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2018-11-26 13:57:31 +08:00
Lukas Auer
c55309c091 riscv: fix inconsistent use of spaces and tabs in start.S
start.S uses both tabs and spaces after instructions. Fix this by only
using tabs after instructions.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2018-11-26 13:57:31 +08:00
Bin Meng
b5369c5813 riscv: Make start.S available for all targets
Currently start.S is inside arch/riscv/cpu/ax25/, but it can be
common for all RISC-V targets.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2018-10-03 17:48:14 +08:00