- Simplify the amount of work that has be done for each architecture by
pushing more of the truly MI code down into the PCI bus driver.
- Don't bind MSI-X indicies to IRQs so that we can allow a driver to map
multiple MSI-X messages into a single IRQ when handling a message
shortage.
The changes include:
- Add a new pcib_if method: PCIB_MAP_MSI() which is called by the PCI bus
to calculate the address and data values for a given MSI/MSI-X IRQ.
The x86 nexus drivers map this into a call to a new 'msi_map()' function
in msi.c that does the mapping.
- Retire the pcib_if method PCIB_REMAP_MSIX() and remove the 'index'
parameter from PCIB_ALLOC_MSIX(). MD code no longer has any knowledge
of the MSI-X index for a given MSI-X IRQ.
- The PCI bus driver now stores more MSI-X state in a child's ivars.
Specifically, it now stores an array of IRQs (called "message vectors" in
the code) that have associated address and data values, and a small
virtual version of the MSI-X table that specifies the message vector
that a given MSI-X table entry uses. Sparse mappings are permitted in
the virtual table.
- The PCI bus driver now configures the MSI and MSI-X address/data
registers directly via custom bus_setup_intr() and bus_teardown_intr()
methods. pci_setup_intr() invokes PCIB_MAP_MSI() to determine the
address and data values for a given message as needed. The MD code
no longer has to call back down into the PCI bus code to set these
values from the nexus' bus_setup_intr() handler.
- The PCI bus code provides a callout (pci_remap_msi_irq()) that the MD
code can call to force the PCI bus to re-invoke PCIB_MAP_MSI() to get
new values of the address and data fields for a given IRQ. The x86
MSI code uses this when an MSI IRQ is moved to a different CPU, requiring
a new value of the 'address' field.
- The x86 MSI psuedo-driver loses a lot of code, and in fact the separate
MSI/MSI-X pseudo-PICs are collapsed down into a single MSI PIC driver
since the only remaining diff between the two is a substring in a
bootverbose printf.
- The PCI bus driver will now restore MSI-X state (including programming
entries in the MSI-X table) on device resume.
- The interface for pci_remap_msix() has changed. Instead of accepting
indices for the allocated vectors, it accepts a mini-virtual table
(with a new length parameter). This table is an array of u_ints, where
each value specifies which allocated message vector to use for the
corresponding MSI-X message. A vector of 0 forces a message to not
have an associated IRQ. The device may choose to only use some of the
IRQs assigned, in which case the unused IRQs must be at the "end" and
will be released back to the system. This allows a driver to use the
same remap table for different shortage values. For example, if a driver
wants 4 messages, it can use the same remap table (which only uses the
first two messages) for the cases when it only gets 2 or 3 messages and
in the latter case the PCI bus will release the 3rd IRQ back to the
system.
MFC after: 1 month
- First off, device drivers really do need to know if they are allocating
MSI or MSI-X messages. MSI requires allocating powerof2() messages for
example where MSI-X does not. To address this, split out the MSI-X
support from pci_msi_count() and pci_alloc_msi() into new driver-visible
functions pci_msix_count() and pci_alloc_msix(). As a result,
pci_msi_count() now just returns a count of the max supported MSI
messages for the device, and pci_alloc_msi() only tries to allocate MSI
messages. To get a count of the max supported MSI-X messages, use
pci_msix_count(). To allocate MSI-X messages, use pci_alloc_msix().
pci_release_msi() still handles both MSI and MSI-X messages, however.
As a result of this change, drivers using the existing API will only
use MSI messages and will no longer try to use MSI-X messages.
- Because MSI-X allows for each message to have its own data and address
values (and thus does not require all of the messages to have their
MD vectors allocated as a group), some devices allow for "sparse" use
of MSI-X message slots. For example, if a device supports 8 messages
but the OS is only able to allocate 2 messages, the device may make the
best use of 2 IRQs if it enables the messages at slots 1 and 4 rather
than default of using the first N slots (or indicies) at 1 and 2. To
support this, add a new pci_remap_msix() function that a driver may call
after a successful pci_alloc_msix() (but before allocating any of the
SYS_RES_IRQ resources) to allow the allocated IRQ resources to be
assigned to different message indices. For example, from the earlier
example, after pci_alloc_msix() returned a value of 2, the driver would
call pci_remap_msix() passing in array of integers { 1, 4 } as the
new message indices to use. The rid's for the SYS_RES_IRQ resources
will always match the message indices. Thus, after the call to
pci_remap_msix() the driver would be able to access the first message
in slot 1 at SYS_RES_IRQ rid 1, and the second message at slot 4 at
SYS_RES_IRQ rid 4. Note that the message slots/indices are 1-based
rather than 0-based so that they will always correspond to the rid
values (SYS_RES_IRQ rid 0 is reserved for the legacy INTx interrupt).
To support this API, a new PCIB_REMAP_MSIX() method was added to the
pcib interface to change the message index for a single IRQ.
Tested by: scottl
pcib_alloc_msix() methods instead of using the method from the generic
PCI-PCI bridge driver as the PCI-PCI methods will be gaining some PCI-PCI
specific logic soon.
- Add a new apic_alloc_vectors() method to the local APIC support code
to allocate N contiguous IDT vectors (aligned on a M >= N boundary).
This function is used to allocate IDT vectors for a group of MSI
messages.
- Add MSI and MSI-X PICs. The PIC code here provides methods to manage
edge-triggered MSI messages as x86 interrupt sources. In addition to
the PIC methods, msi.c also includes methods to allocate and release
MSI and MSI-X messages. For x86, we allow for up to 128 different
MSI IRQs starting at IRQ 256 (IRQs 0-15 are reserved for ISA IRQs,
16-254 for APIC PCI IRQs, and IRQ 255 is reserved).
- Add pcib_(alloc|release)_msi[x]() methods to the MD x86 PCI bridge
drivers to bubble the request up to the nexus driver.
- Add pcib_(alloc|release)_msi[x]() methods to the x86 nexus drivers that
ask the MSI PIC code to allocate resources and IDT vectors.
MFC after: 2 months
various pcib drivers to use their own private devclass_t variables for
their modules.
- Use the DEFINE_CLASS_0() macro to declare drivers for the various pcib
drivers while I'm here.
duplicated anyways) and into a single MI driver. Extend the driver a bit
to implement the bus and PCI kobj interfaces such that other drivers can
attach to it and transparently act as if their parent device is the PCI
bus (for the most part).
other OSes (Solaris, Linux, VxWorks). It's not necessary to write a 0
to the config address register when using config mechanism 1 to turn
off config access. In fact, it can be downright troublesome, since it
seems to confuse the PCI-PCI bridge in the AMD8111 chipset and cause
it to sporadically botch reads from some devices. This is the cause
of the missing USP ports problem I was experiencing with my Sun Opteron
system.
Also correct the case for mechanism 2: it's only necessary to write
a 0 to the ENABLE port.
all the ancient Intel/VIA/SIS/etc chipsets on amd64 systems. Even the
newer intel stuff won't need this since we use acpi by default and we
don't have all their magic programming information. Just use a generic
"Host to PCI bridge" name if we ever hit this code.
- This is heavily derived from John Baldwin's apic/pci cleanup on i386.
- I have completely rewritten or drastically cleaned up some other parts.
(in particular, bootstrap)
- This is still a WIP. It seems that there are some highly bogus bioses
on nVidia nForce3-150 boards. I can't stress how broken these boards
are. I have a workaround in mind, but right now the Asus SK8N is broken.
The Gigabyte K8NPro (nVidia based) is also mind-numbingly hosed.
- Most of my testing has been with SCHED_ULE. SCHED_4BSD works.
- the apic and acpi components are 'standard'.
- If you have an nVidia nForce3-150 board, you are stuck with 'device
atpic' in addition, because they somehow managed to forget to connect the
8254 timer to the apic, even though its in the same silicon! ARGH!
This directly violates the ACPI spec.
- Add a new PCIM_HDRTYPE constant for the field in PCIR_HDRTYPE that holds
the header type.
- Replace several magic numbers with appropriate constants for the header
type register and a couple of PCI_FUNCMAX.
- Merge to amd64 the fix to the i386 bridge code to skip devices with
unknown header types.
Requested by: imp (1, 2)
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.
