aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/xen/xen-pciback/conf_space.h
Commit message (Collapse)AuthorAgeFilesLines
* xen/pciback: Drop two backends, squash and cleanup some code.Konrad Rzeszutek Wilk2011-07-191-21/+21
| | | | | | | | | | | | | | | | | | | | | | - Remove the slot and controller controller backend as they are not used. - Document the find pciback_[read|write]_config_[byte|word|dword] to make it easier to find. - Collapse the code from conf_space_capability_msi into pciback_ops.c - Collapse conf_space_capability_[pm|vpd].c in conf_space_capability.c [and remove the conf_space_capability.h file] - Rename all visible functions from pciback to xen_pcibk. - Rename all the printk/pr_info, etc that use the "pciback" to say "xen-pciback". - Convert functions that are not referenced outside the code to be static to save on name space. - Do the same thing for structures that are internal to the driver. - Run checkpatch.pl after the renames and fixup its warnings and fix any compile errors caused by the variable rename - Cleanup any structs that checkpath.pl commented about or just look odd. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/pciback: xen pci backend driver.Konrad Rzeszutek Wilk2011-07-191-0/+126
This is the host side counterpart to the frontend driver in drivers/pci/xen-pcifront.c. The PV protocol is also implemented by frontend drivers in other OSes too, such as the BSDs. The PV protocol is rather simple. There is page shared with the guest, which has the 'struct xen_pci_sharedinfo' embossed in it. The backend has a thread that is kicked every-time the structure is changed and based on the operation field it performs specific tasks: XEN_PCI_OP_conf_[read|write]: Read/Write 0xCF8/0xCFC filtered data. (conf_space*.c) Based on which field is probed, we either enable/disable the PCI device, change power state, read VPD, etc. The major goal of this call is to provide a Physical IRQ (PIRQ) to the guest. The PIRQ is Xen hypervisor global IRQ value irrespective of the IRQ is tied in to the IO-APIC, or is a vector. For GSI type interrupts, the PIRQ==GSI holds. For MSI/MSI-X the PIRQ value != Linux IRQ number (thought PIRQ==vector). Please note, that with Xen, all interrupts (except those level shared ones) are injected directly to the guest - there is no host interaction. XEN_PCI_OP_[enable|disable]_msi[|x] (pciback_ops.c) Enables/disables the MSI/MSI-X capability of the device. These operations setup the MSI/MSI-X vectors for the guest and pass them to the frontend. When the device is activated, the interrupts are directly injected in the guest without involving the host. XEN_PCI_OP_aer_[detected|resume|mmio|slotreset]: In case of failure, perform the appropriate AER commands on the guest. Right now that is a cop-out - we just kill the guest. Besides implementing those commands, it can also - hide a PCI device from the host. When booting up, the user can specify xen-pciback.hide=(1:0:0)(BDF..) so that host does not try to use the device. The driver was lifted from linux-2.6.18.hg tree and fixed up so that it could compile under v3.0. Per suggestion from Jesse Barnes moved the driver to drivers/xen/xen-pciback. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>