Revision 71e605f8
| ID | 71e605f80313a632cc6714cde7bd240042dbdd95 |
Fix lost serial TX interrupts. Report receive overruns.
o Implement receive overrun status. The FreeBSD uart driver
relies on this status in it's probe routine to determine the size
of the FIFO supported.
o As per the 16550 spec, do not overwrite the RX FIFO on an RX overrun.
o Do not allow TX or RX FIFO overruns to increment the data valid count
beyond the size of the FIFO.
o For reads of the IIR register, only clear the "TX holding register
emtpy interrupt" if the read reports this interrupt. This is required
by the specification and avoids losing TX interrupts when other,
higher priority interrupts (usually RX) are reported first.
Signed-off-by: Justin T. Gibbs <gibbs@FreeBSD.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Files
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