Subject: [PATCH v4 2/3] powerpc sstep: add support for divde[.] and divdeu[.] instructions

From: Balamuruhan S <[email-masked]>
Date: Tue, 28 Jul 2020 18:33:07 +0530

This patch adds emulation support for divde, divdeu instructions,
	* Divide Doubleword Extended (divde[.])
	* Divide Doubleword Extended Unsigned (divdeu[.])

Reviewed-by: Sandipan Das <[email-masked]>
Signed-off-by: Balamuruhan S <[email-masked]>
Acked-by: Naveen N. Rao <[email-masked]>
---
 arch/powerpc/lib/sstep.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index c58ea9e787cb..caee8cc77e19 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1806,7 +1806,18 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
 			op->val = (int) regs->gpr[ra] /
 				(int) regs->gpr[rb];
 			goto arith_done;
-
+#ifdef __powerpc64__
+		case 425:	/* divde[.] */
+			asm volatile(PPC_DIVDE(%0, %1, %2) :
+				"=r" (op->val) : "r" (regs->gpr[ra]),
+				"r" (regs->gpr[rb]));
+			goto arith_done;
+		case 393:	/* divdeu[.] */
+			asm volatile(PPC_DIVDEU(%0, %1, %2) :
+				"=r" (op->val) : "r" (regs->gpr[ra]),
+				"r" (regs->gpr[rb]));
+			goto arith_done;
+#endif
 		case 755:	/* darn */
 			if (!cpu_has_feature(CPU_FTR_ARCH_300))
 				return -1;
-- 
2.24.1