Commit 381ad384 authored Nov 03, 2020 by Tiezhu Yang Committed by Thomas Bogendoerfer Nov 11, 2020

MIPS: Loongson64: SMP: Fix up play_dead jump indicator



In play_dead function, the whole 64-bit PC mailbox was used as a indicator
to determine if the master core had written boot jump information.

However, after we introduced CSR mailsend, the hardware will not guarante
an atomic write for the 64-bit PC mailbox. Thus we have to use the lower
32-bit which is written at the last as the jump indicator instead.

Signed-off-by: Lu Zeng <zenglu@loongson.cn>
Signed-off-by: Jun Yi <yijun@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

parent fed4955f

arch/mips/loongson64/smp.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -764,9 +764,10 @@ static void loongson3_type3_play_dead(int *state_addr)
		"1: li %[count], 0x100 \n" /* wait for init loop */
		"2: bnez %[count], 2b \n" /* limit mailbox access */
		" addiu %[count], -1 \n"
		" ld %[initfunc], 0x20(%[base]) \n" /* get PC via mailbox */
		" lw %[initfunc], 0x20(%[base]) \n" /* check lower 32-bit as jump indicator */
		" beqz %[initfunc], 1b \n"
		" nop \n"
		" ld %[initfunc], 0x20(%[base]) \n" /* get PC (whole 64-bit) via mailbox */
		" ld $sp, 0x28(%[base]) \n" /* get SP via mailbox */
		" ld $gp, 0x30(%[base]) \n" /* get GP via mailbox */
		" ld $a1, 0x38(%[base]) \n"