John Baldwin e706f7f0c7 Revamp the MSI/MSI-X code a bit to achieve two main goals: ... - 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		2007-05-02 17:50:36 +00:00
..
pci_bus.c	Revamp the MSI/MSI-X code a bit to achieve two main goals:	2007-05-02 17:50:36 +00:00
pci_cfgreg.c	Replace a few magic numbers.	2006-12-12 19:23:52 +00:00
pci_pir.c	Don't dump the $PIR table under bootverbose. The pirtool program in	2006-11-09 18:03:36 +00:00