a heavily stripped down FreeBSD/i386 (brutally stripped down actually) to
attempt to get a stable base to start from. There is a lot missing still.
Worth noting:
- The kernel runs at 1GB in order to cheat with the pmap code. pmap uses
a variation of the PAE code in order to avoid having to worry about 4
levels of page tables yet.
- It boots in 64 bit "long mode" with a tiny trampoline embedded in the
i386 loader. This simplifies locore.s greatly.
- There are still quite a few fragments of i386-specific code that have
not been translated yet, and some that I cheated and wrote dumb C
versions of (bcopy etc).
- It has both int 0x80 for syscalls (but using registers for argument
passing, as is native on the amd64 ABI), and the 'syscall' instruction
for syscalls. int 0x80 preserves all registers, 'syscall' does not.
- I have tried to minimize looking at the NetBSD code, except in a couple
of places (eg: to find which register they use to replace the trashed
%rcx register in the syscall instruction). As a result, there is not a
lot of similarity. I did look at NetBSD a few times while debugging to
get some ideas about what I might have done wrong in my first attempt.
#if'ed out for a while. Complete the deed and tidy up some other bits.
We need to be able to call this stuff from outer edges of interrupt
handlers for devices that have the ISR bits in pci config space. Making
the bios code mpsafe was just too hairy. We had also stubbed it out some
time ago due to there simply being too much brokenness in too many systems.
This adds a leaf lock so that it is safe to use pci_read_config() and
pci_write_config() from interrupt handlers. We still will use pcibios
to do interrupt routing if there is no acpi.. [yes, I tested this]
Briefly glanced at by: imp
o It turns out that we always need to try to route the interrupts for
the case where the $PIR tells us there can be only one. Some machines
require this, while others fail when we try to do this (bogusly, imho).
Since we have no apriori way of knowing which is which, we always try to
do the routing and hope for the best if things fail.
o Add some additional comments that state the obvious, but amplify it in
non-obvious ways (judging from the questions I've gotten).
This should un-break older laptops that still have to use PCIBIOS to route
interrupts.
Tested by: sam
Use exact width types, since this is a MD file and won't be used elsewhere.
Fix a couple of resulting printf breakages
Bug found by: phk using Flexlint
there are some strange machines that seem to need this.
o delete bogus comment.
o don't use the the bios for read/writing config space. They interact badly
with SMP and being called from ISR. This brings -current in line with
-stable.
# make the latter #ifdef on USE_PCI_BIOS_FOR_READ_WRITE in case we
# need to go back in a hurry.
These are still unknown name but these are working as well
as the other ServerWorks chipset.
Description strings should be corrected when the chipsets
are known.
MFC after: 1 week
route interrupts if the child bus is described in the PCIBIOS interrupt
routing table. For child busses that are in the routing table, they do
not necessarily use a 'swizzle' on their pins on the parent bus to route
interrupts for child devices. If the child bus is an embedded device then
the pins on the child devices can be (and usually are) directly connected
either to a PIC or to a Interrupt Router. This fixes PCIBIOS interrupt
routing across PCI-PCI bridges for embedded devices.
IRQ for an entry in a PCIBIOS interrupt routing ($PIR) table.
- Change pci_cfgintr() to except the current IRQ of a device as a fourth
argument and to use that IRQ for the device if it is valid.
- If an intpin entry in a $PIR entry has a link of 0, it means that that
intpin isn't connected to anything that can trigger an interrupt. Thus,
test the link against 0 to find invalid entries in the table instead of
implicitly relying on the irqs field to be zero. In the machines I have
looked at, intpin entries with a link of 0 often have the bits for all
possible interrupts for PCI devices set.
not the 'entry' member. The entry point is formed from both a base and
a relative entry point. 'entry' is that relative offset. It is perfectly
valid to have an entry point with a relative offset of 0. PCIbios.ventry
is the virtual address of the entry point that takes both 'base' and
'entry' into account, thus it is the proper variable to test to see if we
have an entry point or not.
identify this gadget on the CPUID result alone, so I intend to activate
the necessary magic (i8254 frequency for instance) for it based on the
precense of the on-chip host to PCI bridge.
Don't require pin be non-zero before we map bogus intlines, always do it.
This fixes a number of problems on HP Omnibook computers.
Tested/Reviewed by: Brooks Davis
2, but that's not the case. This fixes the case where there were slots
in the PIR table that had no bits set, but we assumed they did and used
strange results as a result.
o Map invalid INTLINE registers to 255 in pci_cfgreg.c. This should allow
us to remove the bogus checks in MI code for non-255 values.
I put these changes out for review a while ago, but no one responded
to them, so into current they go.
This should help us work better on machines that don't route
interrupts in the traditional way.
MFC After: 4286 millifortnights
older PCI BIOSes hate this and this leads to panics when it is done. Also,
assume that a uniquely routed interrupt is already routed. This also
seems to help some older laptops with feable BIOSes cope.
This typo keeps us from properly routing an interrupt for CardBus
bridges on this machine. So, now we look for $PIR and then _PIR to
cope. With these changes, the Libretto L1 now works properly.
Evidentally, the idea comes from patch that the Japanese version of
RedHat (or against a Japanese version of Red Hat), but my Japanese
isn't good enough to to know for sure.
Reported by: Hiroyuki Aizu-san <eyes@navi.org>
# This may be an MFC candidate, but I'm not yet sure.
Merge in the irq 0 detection. Add comment about why.
If we have irq 0, ignore it like we do irq 255. Some BIOS writers aren't
careful like they should be.
multiple times, others do. The last strategy, which was to assume
that already routed interrupts were good and just return them doesn't
work for some laptops. So, instead, we have a new strategy: we notice
that we have an interrupt that's already routed. We go ahead and try
to route it, none the less. We will assume that it is correctly
routed, even if the route fails. We still assume that other failures
in the bios32 call are because the interrupt is NOT routed.
Note: some laptops do not support the bios32 interface to PCI BIOS and
we need to call it via the INT 2A interface. That is another windmill
to till at later.
Also correct a minor typo and minor whitespace nits.
Strong MFC candidate.
and such was just a bad idea and one that users should be forced to
enable if they want it. This patch introduces a hw.pci.enable_pcibios
tunable for those people. This does not impact the pcibios interrupt
routing at all.
Approved by: peter, msmith
some bios vendors took it apon themselves to "censor" the
host->pci bridges from PCIBIOS callers, even when the caller
explicitly asks for them. This includes certain Compaq machines
(eg: DL360) and some laptops.
If we detect this, shut down pcibios and revert to using IO
port bashing.
Under -current, apcica does a better job anyway.
