From: Guo Ren Date: Thu, 19 Oct 2023 09:27:34 +0000 (-0400) Subject: firmware: fw_base.S: Fix boot hart status synchronization X-Git-Tag: v1.4~63 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fccdf41d32877eca0cef3789d12a197cba73c2e2;p=platform%2Fkernel%2Fopensbi.git firmware: fw_base.S: Fix boot hart status synchronization It's wrong to put the fence after setting the boot status flag because all relocation operations must be finished before setting the status flag. So, this fence must be put before the setting status flag, and there is no use in putting a fence between _start_warm and setting status flag. Also, nop can't delay other harts too much, so use div instead, just like Linux cpu_relax. Current opensbi force enables “M” Standard Extension, and mul instructions have been used in the fw_base.S. After the above two fixes, the boot hart index param of the fw_dynamic_info could be guaranteed properly for all platforms. Signed-off-by: Guo Ren Signed-off-by: Guo Ren Reviewed-by: Anup Patel --- diff --git a/firmware/fw_base.S b/firmware/fw_base.S index 42b03fe..f7763f4 100644 --- a/firmware/fw_base.S +++ b/firmware/fw_base.S @@ -399,8 +399,8 @@ _fdt_reloc_done: /* mark boot hart done */ li t0, BOOT_STATUS_BOOT_HART_DONE lla t1, _boot_status - REG_S t0, 0(t1) fence rw, rw + REG_S t0, 0(t1) j _start_warm /* waiting for boot hart to be done (_boot_status == 2) */ @@ -409,9 +409,9 @@ _wait_for_boot_hart: lla t1, _boot_status REG_L t1, 0(t1) /* Reduce the bus traffic so that boot hart may proceed faster */ - nop - nop - nop + div t2, t2, zero + div t2, t2, zero + div t2, t2, zero bne t0, t1, _wait_for_boot_hart _start_warm: