Hi Bo Gan, > From: Bo Gan <ganbo...@gmail.com> > Sent: Tuesday, May 09, 2023 9:46 AM > To: u-boot@lists.denx.de > Cc: Bo Gan <ganbo...@gmail.com>; Rick Jian-Zhi Chen(陳建志) > <r...@andestech.com>; Leo Yu-Chi Liang(梁育齊) <ycli...@andestech.com> > Subject: [PATCH] riscv: setup per-hart stack earlier > > Harts need to use per-hart stack before any function call, even if that > function is a simple one. When the callee uses stack for register save/ > restore, especially RA, if nested call, concurrent access by multiple harts > on the same stack will cause data-race. > > This patch sets up SP before `board_init_f_alloc_reserve`. A side effect of > this is that the memory layout has changed as the following: > > +----------------+ +----------------+ <----- SPL_STACK/ > | ...... | | hart 0 stack | SYS_INIT_SP_ADDR > | malloc_base | +----------------+ > +----------------+ | hart 1 stack | > | GD | +----------------+ If not SMP, N=1 > +----------------+ | ...... | > | hart 0 stack | +----------------+ > +----------------+ ==> | hart N-1 stack| > | hart 1 stack | +----------------+ > +----------------+ | ...... | > | ...... | | malloc_base | > +----------------+ +----------------+ > | hart N-1 stack| | GD | > +----------------+ +----------------+ > | | | | > > Signed-off-by: Bo Gan <ganbo...@gmail.com> > Cc: Rick Chen <r...@andestech.com> > Cc: Leo <ycli...@andestech.com> > --- > arch/riscv/cpu/start.S | 37 ++++++++++++++++++++++++------------- > 1 file changed, 24 insertions(+), 13 deletions(-) > > diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S index > dad22bf..90015c2 100644 > --- a/arch/riscv/cpu/start.S > +++ b/arch/riscv/cpu/start.S > @@ -91,16 +91,35 @@ _start: > * Set stackpointer in internal/ex RAM to call board_init_f > */ > call_board_init_f: > - li t0, -16 > #if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_STACK) > - li t1, CONFIG_SPL_STACK > + li t0, CONFIG_SPL_STACK > #else > - li t1, SYS_INIT_SP_ADDR > + li t0, CONFIG_SYS_INIT_SP_ADDR
It builds fail as below: arch/riscv/cpu/start.S:97: Error: illegal operands `li t0,CONFIG_SYS_INIT_SP_ADDR' Thanks, Rick
