Commit 4e43e5df authored Sep 21, 2020 by Huacai Chen Committed by Thomas Bogendoerfer Sep 21, 2020

MIPS: context switch: Use save/restore instead of set/clear for Status.CU2



Some processors (such as Loongson-3) need to enable CU2 in kernel mode,
current set/clear method will lose Status.CU2 during context switching,
so use save/restore method instead.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

parent 6fa573a3

arch/mips/include/asm/switch_to.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -117,6 +117,8 @@ do { \
		__restore_dsp(next); \
		} \
		if (cop2_present) { \
		u32 status = read_c0_status(); \
		\
		set_c0_status(ST0_CU2); \
		if ((KSTK_STATUS(prev) & ST0_CU2)) { \
		if (cop2_lazy_restore) \
		@@ -127,7 +129,7 @@ do { \
		!cop2_lazy_restore) { \
		cop2_restore(next); \
		} \
		clear_c0_status(ST0_CU2); \
		write_c0_status(status); \
		} \
		__clear_r5_hw_ll_bit(); \
		__clear_software_ll_bit(); \