[Qemu-devel] [PULL 21/58] lsi: never set DMA FIFO Empty (DFE) bit in DSTAT register

[Paolo Bonzini]

From: Hervé Poussineau <address@hidden>

53C895A datasheet says:
"This bit (DFE) is a pure status bit and will not cause an interrupt"

This bit is already auto-generated in lsi_read_reg when reading the DSTAT 
register.

This fixes IBM RS/6000 7020 firmware, which is:
- resetting the adapter
- enabling all interrupt sources (including DIP, ie interrupts from DSTAT)
- waiting for ISTAT0 to become 0 (including DIP=0, ie no interrupt coming from 
DSTAT)

Signed-off-by: Hervé Poussineau <address@hidden>
Message-Id: <address@hidden>
Signed-off-by: Paolo Bonzini <address@hidden>
Signed-off-by: Hervé Poussineau <address@hidden>
---
 hw/scsi/lsi53c895a.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
index 2e99d5e..feb1191 100644
--- a/hw/scsi/lsi53c895a.c
+++ b/hw/scsi/lsi53c895a.c
@@ -326,7 +326,7 @@ static void lsi_soft_reset(LSIState *s)
     s->istat0 = 0;
     s->istat1 = 0;
     s->dcmd = 0x40;
-    s->dstat = LSI_DSTAT_DFE;
+    s->dstat = 0;
     s->dien = 0;
     s->sist0 = 0;
     s->sist1 = 0;
-- 
1.8.3.1