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author | jhb <jhb@FreeBSD.org> | 2006-11-13 21:47:30 +0000 |
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committer | jhb <jhb@FreeBSD.org> | 2006-11-13 21:47:30 +0000 |
commit | d055bdf0ca2fa4ba26cc9a2bf7648eff24fb1cdd (patch) | |
tree | 345f410ac1e147632cdb6f75911e415f0d11e563 /sys/dev/pci/pci_if.m | |
parent | da229fb2a54f22882db72f2fc7f5eaea1691bc81 (diff) | |
download | FreeBSD-src-d055bdf0ca2fa4ba26cc9a2bf7648eff24fb1cdd.zip FreeBSD-src-d055bdf0ca2fa4ba26cc9a2bf7648eff24fb1cdd.tar.gz |
First cut at MI support for PCI Message Signalled Interrupts (MSI):
- Add 3 new functions to the pci_if interface along with suitable wrappers
to provide the device driver visible API:
- pci_alloc_msi(dev, int *count) backed by PCI_ALLOC_MSI(). '*count'
here is an in and out parameter. The driver stores the desired number
of messages in '*count' before calling the function. On success,
'*count' holds the number of messages allocated to the device. Also on
success, the driver can access the messages as SYS_RES_IRQ resources
starting at rid 1. Note that the legacy INTx interrupt resource will
not be available when using MSI. Note that this function will allocate
either MSI or MSI-X messages depending on the devices capabilities and
the 'hw.pci.enable_msix' and 'hw.pci.enable_msi' tunables. Also note
that the driver should activate the memory resource that holds the
MSI-X table and pending bit array (PBA) before calling this function
if the device supports MSI-X.
- pci_release_msi(dev) backed by PCI_RELEASE_MSI(). This function
releases the messages allocated for this device. All of the
SYS_RES_IRQ resources need to be released for this function to succeed.
- pci_msi_count(dev) backed by PCI_MSI_COUNT(). This function returns
the maximum number of MSI or MSI-X messages supported by this device.
MSI-X is preferred if present, but this function will honor the
'hw.pci.enable_msix' and 'hw.pci.enable_msi' tunables. This function
should return the largest value that pci_alloc_msi() can return
(assuming the MD code is able to allocate sufficient backing resources
for all of the messages).
- Add default implementations for these 3 methods to the pci_driver generic
PCI bus driver. (The various other PCI bus drivers such as for ACPI and
OFW will inherit these default implementations.) This default
implementation depends on 4 new pcib_if methods that bubble up through
the PCI bridges to the MD code to allocate IRQ values and perform any
needed MD setup code needed:
- PCIB_ALLOC_MSI() attempts to allocate a group of MSI messages.
- PCIB_RELEASE_MSI() releases a group of MSI messages.
- PCIB_ALLOC_MSIX() attempts to allocate a single MSI-X message.
- PCIB_RELEASE_MSIX() releases a single MSI-X message.
- Add default implementations for these 4 methods that just pass the
request up to the parent bus's parent bridge driver and use the
default implementation in the various MI PCI bridge drivers.
- Add MI functions for use by MD code when managing MSI and MSI-X
interrupts:
- pci_enable_msi(dev, address, data) programs the MSI capability address
and data registers for a group of MSI messages
- pci_enable_msix(dev, index, address, data) initializes a single MSI-X
message in the MSI-X table
- pci_mask_msix(dev, index) masks a single MSI-X message
- pci_unmask_msix(dev, index) unmasks a single MSI-X message
- pci_pending_msix(dev, index) returns true if the specified MSI-X
message is currently pending
- Save the MSI capability address and data registers in the pci_cfgreg
block in a PCI devices ivars and restore the values when a device is
resumed. Note that the MSI-X table is not currently restored during
resume.
- Add constants for MSI-X register offsets and fields.
- Record interesting data about any MSI-X capability blocks we come
across in the pci_cfgreg block in the ivars for PCI devices.
Tested on: em (i386, MSI), bce (amd64/i386, MSI), mpt (amd64, MSI-X)
Reviewed by: scottl, grehan, jfv
MFC after: 2 months
Diffstat (limited to 'sys/dev/pci/pci_if.m')
-rw-r--r-- | sys/dev/pci/pci_if.m | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/sys/dev/pci/pci_if.m b/sys/dev/pci/pci_if.m index df2456a..ba60415 100644 --- a/sys/dev/pci/pci_if.m +++ b/sys/dev/pci/pci_if.m @@ -30,6 +30,15 @@ INTERFACE pci; +CODE { + static int + null_msi_count(device_t dev, device_t child) + { + return (0); + } +}; + + METHOD u_int32_t read_config { device_t dev; device_t child; @@ -102,3 +111,19 @@ METHOD int find_extcap { int capability; int *capreg; }; + +METHOD int alloc_msi { + device_t dev; + device_t child; + int *count; +}; + +METHOD int release_msi { + device_t dev; + device_t child; +}; + +METHOD int msi_count { + device_t dev; + device_t child; +} DEFAULT null_msi_count; |