firewire: ohci: do not start DMA contexts before link is enabled
OHCI 1.1 5.7.3 not only forbids enabling or starting any DMA contexts
before the linkEnable bit is set, but also explicitly warns of undefined
behaviour if this order is violated.
Don't violate it then.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index f903d7b6..dfb3cb7 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -2066,8 +2066,6 @@
reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
reg_write(ohci, OHCI1394_LinkControlSet,
- OHCI1394_LinkControl_rcvSelfID |
- OHCI1394_LinkControl_rcvPhyPkt |
OHCI1394_LinkControl_cycleTimerEnable |
OHCI1394_LinkControl_cycleMaster);
@@ -2094,9 +2092,6 @@
reg_write(ohci, OHCI1394_FairnessControl, 0);
card->priority_budget_implemented = ohci->pri_req_max != 0;
- ar_context_run(&ohci->ar_request_ctx);
- ar_context_run(&ohci->ar_response_ctx);
-
reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
reg_write(ohci, OHCI1394_IntEventClear, ~0);
reg_write(ohci, OHCI1394_IntMaskClear, ~0);
@@ -2186,7 +2181,13 @@
reg_write(ohci, OHCI1394_HCControlSet,
OHCI1394_HCControl_linkEnable |
OHCI1394_HCControl_BIBimageValid);
- flush_writes(ohci);
+
+ reg_write(ohci, OHCI1394_LinkControlSet,
+ OHCI1394_LinkControl_rcvSelfID |
+ OHCI1394_LinkControl_rcvPhyPkt);
+
+ ar_context_run(&ohci->ar_request_ctx);
+ ar_context_run(&ohci->ar_response_ctx); /* also flushes writes */
/* We are ready to go, reset bus to finish initialization. */
fw_schedule_bus_reset(&ohci->card, false, true);