[HAL]: Implement support for Level interrupts, which are used by certain EISA cards, and more particularly, all PCI hardware. Level interrupts were not previously handled correctly, being treated as edge/latched interrupts instead.
[NTOS/HAL]: Remove VDM Alert KPCR hack (which was buggy). Now the PKTRAP_FRAME is passed as a parameter to HalpEndSoftwareInterrupt/HalEndSystemInterrupt. This also removes the HalpNestedTrap ASM hack, since the call can now be done in C.
[PERF]: On real machines, writing the PIC mask is a relatively expensive I/O operation, and IRQL lower/raise can happen hundreds of times a second. Lazy IRQL provides an important optimization.
[PERF]: Correctly handling level interrupts as level interrupts allows for faster, and more efficient, IRQ handling.
svn path=/trunk/; revision=45320
[NTOS]: Remove said hacks and have a normal C implementation of KeUpdateSystemTime. It exits the interrupt through a soft interrupt exit.
[NTOS]: Implement 4 lines of support code needed to handle interrupts during V8086 mode, which were lacking since we weren't hitting this case yet.
Note that now the KeUpdateSystemTime interface is not "compatible" with Windows anymore. This does not matter, since the only possible caller of KeUpdateSystemTime is a very specific HAL routine that needs a very specific stack layout to actually work, so the chance of anyone calling this API is absolutely zero (no, not even some experimental driver. It's absolutely impossible).
svn path=/trunk/; revision=45276
[NTOS]: Implement KiComputeTimerTableIndex in C instead of ASM. Based off eVb's ARM implementation, bugfixed to do correct math instead.
As a side effect, this should fix timers on ARM ;-)
svn path=/trunk/; revision=45140