[haiku-commits] haiku: hrev44689 - src/add-ons/kernel/busses/usb
- From: korli@xxxxxxxxxxxxxxxx
- To: haiku-commits@xxxxxxxxxxxxx
- Date: Tue, 9 Oct 2012 23:04:10 +0200 (CEST)
hrev44689 adds 1 changeset to branch 'master'
old head: c530d46cca3cb9bde36e243e634796eb2e17a23a
new head: 3b98be3cc44741c04fefddc14d7b34a7735468a2
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3b98be3: USB OHCI: Fix ownership handover from SMM to OS.
* Disabling all interrupts prior to ownership handover from SMM to OS
can prevent propper OHCI and PS/2 functionality as described in
#8987 and #8984. In that case SMM does not respond to the ownership
change request. On the other hand not disabling the interrupts can
lead to interrupt storms (discussed in #8085) since no interrupt
handler is installed at that moment. As suggested by mmlr this patch
attempts to address both issues by keeping the ownership change
request interrupt enabled.
* Removed an unnecessary reset upon non-responding SMM for now,
since we reset a few lines later anyway and added TODOs respectively.
That should safe a bit boot time.
Signed-off-by: Michael Lotz <mmlr@xxxxxxxx>
[ JÃrgen Wall <fakeEmail@xxxxxxxxxxxxx> ]
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Revision: hrev44689
Commit: 3b98be3cc44741c04fefddc14d7b34a7735468a2
URL: http://cgit.haiku-os.org/haiku/commit/?id=3b98be3
Author: JÃrgen Wall <fakeEmail@xxxxxxxxxxxxx>
Date: Thu Oct 4 21:17:45 2012 UTC
Committer: JÃrÃme Duval <jerome.duval@xxxxxxxxx>
Commit-Date: Tue Oct 9 21:03:06 2012 UTC
Ticket: https://dev.haiku-os.org/ticket/8085
Ticket: https://dev.haiku-os.org/ticket/8984
Ticket: https://dev.haiku-os.org/ticket/8987
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1 file changed, 17 insertions(+), 7 deletions(-)
src/add-ons/kernel/busses/usb/ohci.cpp | 24 +++++++++++++++++-------
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diff --git a/src/add-ons/kernel/busses/usb/ohci.cpp
b/src/add-ons/kernel/busses/usb/ohci.cpp
index df38174..73bc769 100644
--- a/src/add-ons/kernel/busses/usb/ohci.cpp
+++ b/src/add-ons/kernel/busses/usb/ohci.cpp
@@ -206,8 +206,15 @@ OHCI::OHCI(pci_info *info, Stack *stack)
fInterruptEndpoints[0]->next_physical_endpoint
= fDummyIsochronous->physical_address;
- // Disable all interrupts before handoff/reset
- _WriteReg(OHCI_INTERRUPT_DISABLE, OHCI_ALL_INTERRUPTS);
+ // When the handover from SMM takes place, all interrupts are routed to
the
+ // OS. As we don't yet have an interrupt handler installed at this
point,
+ // this may cause interrupt storms if the firmware does not disable the
+ // interrupts during handover. Therefore we disable interrupts before
+ // requesting ownership. We have to keep the ownership change interrupt
+ // enabled though, as otherwise the SMM will not be notified of the
+ // ownership change request we trigger below.
+ _WriteReg(OHCI_INTERRUPT_DISABLE, OHCI_ALL_INTERRUPTS &
+ ~OHCI_OWNERSHIP_CHANGE) ;
// Determine in what context we are running (Kindly copied from FreeBSD)
uint32 control = _ReadReg(OHCI_CONTROL);
@@ -221,9 +228,12 @@ OHCI::OHCI(pci_info *info, Stack *stack)
}
if ((control & OHCI_INTERRUPT_ROUTING) != 0) {
- TRACE_ERROR("smm does not respond. resetting...\n");
- _WriteReg(OHCI_CONTROL, OHCI_HC_FUNCTIONAL_STATE_RESET);
- snooze(USB_DELAY_BUS_RESET);
+ TRACE_ERROR("smm does not respond.\n");
+
+ // TODO: Enable this reset as soon as the non-specified
+ // reset a few lines later is replaced by a better
solution.
+ //_WriteReg(OHCI_CONTROL,
OHCI_HC_FUNCTIONAL_STATE_RESET);
+ //snooze(USB_DELAY_BUS_RESET);
} else
TRACE_ALWAYS("ownership change successful\n");
} else {
@@ -231,8 +241,8 @@ OHCI::OHCI(pci_info *info, Stack *stack)
snooze(USB_DELAY_BUS_RESET);
}
- // This reset should not be necessary according to the OHCI spec, but
- // without it some controllers do not start.
+ // TODO: This reset delays system boot time. It should not be necessary
+ // according to the OHCI spec, but without it some controllers don't
start.
_WriteReg(OHCI_CONTROL, OHCI_HC_FUNCTIONAL_STATE_RESET);
snooze(USB_DELAY_BUS_RESET);
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