drm/radeon: use packet3 for nop on hawaii with new firmware

Older firmware didn't support the new nop packet.

Signed-off-by: Alex Deucher <[e-mail]>
Signed-off-by: Andreas Boll <[e-mail]>

drivers/gpu/drm/radeon/cik.c

···
 	cik_irq_set(rdev);
 
 	if (rdev->family == CHIP_HAWAII) {
-		nop = RADEON_CP_PACKET2;
+		if (rdev->new_fw)
+			nop = PACKET3(PACKET3_NOP, 0x3FFF);
+		else
+			nop = RADEON_CP_PACKET2;
 	} else {
 		nop = PACKET3(PACKET3_NOP, 0x3FFF);
 	}