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authorXiang Wang <wxjstz@126.com>2018-07-11 12:13:00 +0800
committerMartin Roth <martinroth@google.com>2018-07-18 18:56:10 +0000
commit35da319b725805482e4d57571d92cccf65384d63 (patch)
tree75d67caf78b3cc8082b884f0ad1410949a85afdf /src/arch/riscv/bootblock.S
parent3a1a956286d466e0438dc76377db5bdf9fb374ff (diff)
riscv: add CAR interface
Add an interface to support cache as ram. Initialize stack pointer for each hart. Change-Id: Ic3920e01dd1a7f047a53de57250589000a111409 Signed-off-by: Xiang Wang <wxjstz@126.com> Reviewed-on: https://review.coreboot.org/27430 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/arch/riscv/bootblock.S')
-rw-r--r--src/arch/riscv/bootblock.S36
1 files changed, 21 insertions, 15 deletions
diff --git a/src/arch/riscv/bootblock.S b/src/arch/riscv/bootblock.S
index 0b5a2b2961..81a4455d97 100644
--- a/src/arch/riscv/bootblock.S
+++ b/src/arch/riscv/bootblock.S
@@ -34,25 +34,26 @@ _start:
#
csrw mscratch, a1
- # N.B. This only works on low 4G of the address space
- # and the stack must be page-aligned.
- la sp, _estack
-
- # poison the stack
- la t1, _stack
- li t0, 0xdeadbeef
- sd t0, 0(t1)
+ # initialize cache as ram
+ call cache_as_ram
- # make room for HLS and initialize it
- addi sp, sp, -HLS_SIZE
+ # initialize stack point for each hart
+ # and the stack must be page-aligned.
+ # 0xDEADBEEF used to check stack overflow
+ csrr a0, mhartid
+ la t0, _stack
+ slli t1, a0, RISCV_PGSHIFT
+ add t0, t0, t1
+ li t1, 0xDEADBEEF
+ sd t1, 0(t0)
+ li t1, RISCV_PGSIZE - HLS_SIZE
+ add sp, t0, t1
- // Once again, the docs and toolchain disagree.
- // Rather than get fancy I'll just lock this down
- // until it all stabilizes.
- //csrr a0, mhartid
- csrr a0, 0xf14
+ # initialize hart-local storage
+ csrr a0, mhartid
call hls_init
+ # initialize entry of interrupt/exception
la t0, trap_entry
csrw mtvec, t0
@@ -62,3 +63,8 @@ _start:
# set up the mstatus register for VM
call mstatus_init
tail main
+
+ // These codes need to be implemented on a specific SoC.
+ .weak cache_as_ram
+cache_as_ram:
+ ret