From ecf8328e59447b83a1f79628487e0e9f8801db84 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Mon, 11 Apr 2011 09:56:12 +0200 Subject: [PATCH] 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 Signed-off-by: Stefan Richter --- drivers/firewire/ohci.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index f903d7b6f34a..dfb3cb774a79 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -2066,8 +2066,6 @@ static int ohci_enable(struct fw_card *card, 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 @@ static int ohci_enable(struct fw_card *card, 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 @@ static int ohci_enable(struct fw_card *card, 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); -- 2.20.1