According to MIPS EJTAG Specification [1], a Debug Breakpoint exception occurs when an SDBBP instruction is executed, the CP0_DEBUG bit DBp indicates that a Debug Breakpoint exception occurred, just check bit DBp for SDBBP is more accurate. [1] http://www.t-es-t.hu/download/mips/md00047f.pdf Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> --- arch/mips/kernel/genex.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S index bcce32a..6336826 100644 --- a/arch/mips/kernel/genex.S +++ b/arch/mips/kernel/genex.S @@ -349,8 +349,8 @@ NESTED(ejtag_debug_handler, PT_SIZE, sp) MTC0 k0, CP0_DESAVE mfc0 k0, CP0_DEBUG - sll k0, k0, 30 # Check for SDBBP. - bgez k0, ejtag_return + andi k0, k0, 0x2 # Check for SDBBP. + beqz k0, ejtag_return #ifdef CONFIG_SMP 1: PTR_LA k0, ejtag_debug_buffer_spinlock -- 2.1.0
