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Staging: vme: Separate the list of TODOs from the API documentation
This patch moves the API documentation to it's own file and provides a proper list of TODOs. Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Martyn Welch
Greg Kroah-Hartman
parent
3d0f8bc751
commit
bf39f9a5bd
@ -1,388 +1,98 @@
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VME Device Driver API
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TODO
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=====================
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====
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Driver registration
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API
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===================
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===
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As with other subsystems within the Linux kernel, VME device drivers register
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DMA Resource Allocation incomplete
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with the VME subsystem, typically called from the devices init routine. This is
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----------------------------------
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achieved via a call to the follwoing function:
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int vme_register_driver (struct vme_driver *driver);
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The current DMA resource Allocation provides no means of selecting the
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suitability of a DMA controller based on it's supported modes of operation, as
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opposed to the resource allocation mechanisms for master and slave windows:
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If driver registration is successful this function returns zero, if an error
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struct vme_resource *vme_request_dma(struct device *dev);
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occurred a negative error code will be returned.
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A pointer to a structure of type ???vme_driver??? must be provided to the
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As opposed to:
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registration function. The structure is as follows:
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struct vme_driver {
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struct list_head node;
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char *name;
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const struct vme_device_id *bind_table;
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int (*probe) (struct device *, int, int);
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int (*remove) (struct device *, int, int);
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void (*shutdown) (void);
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struct device_driver driver;
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};
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At the minimum, the ???.name???, ???.probe??? and ???.bind_table??? elements of this
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structure should be correctly set. The ???.name??? element is a pointer to a string
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holding the device driver???s name. The ???.probe??? element should contain a pointer
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to the probe routine.
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The arguments of the probe routine are as follows:
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probe(struct device *dev, int bus, int slot);
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The ???.bind_table??? is a pointer to an array of type ???vme_device_id???:
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struct vme_device_id {
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int bus;
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int slot;
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};
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Each structure in this array should provide a bus and slot number where the core
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should probe, using the driver???s probe routine, for a device on the specified
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VME bus.
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The VME subsystem supports a single VME driver per ???slot???. There are considered
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to be 32 slots per bus, one for each slot-ID as defined in the ANSI/VITA 1-1994
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specification and are analogious to the physical slots on the VME backplane.
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A function is also provided to unregister the driver from the VME core and is
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usually called from the device driver???s exit routine:
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void vme_unregister_driver (struct vme_driver *driver);
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Resource management
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===================
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Once a driver has registered with the VME core the provided probe routine will
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be called for each of the bus/slot combination that becomes valid as VME buses
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are themselves registered. The probe routine is passed a pointer to the devices
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device structure. This pointer should be saved, it will be required for
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requesting VME resources.
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The driver can request ownership of one or more master windows, slave windows
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and/or dma channels. Rather than allowing the device driver to request a
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specific window or DMA channel (which may be used by a different driver) this
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driver allows a resource to be assigned based on the required attributes of the
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driver in question:
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struct vme_resource * vme_master_request(struct device *dev,
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struct vme_resource * vme_master_request(struct device *dev,
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vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
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vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
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struct vme_resource * vme_slave_request(struct device *dev,
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The TSI148 can perform, VME-to-PCI, PCI-to-VME, PATTERN-to-VME, PATTERN-to-PCI,
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vme_address_t aspace, vme_cycle_t cycle);
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VME-to-VME and PCI-to-PCI transfers. The CA91C142 can only provide VME-to-PCI
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and PCI-to-VME.
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TODO: DMA Resource Allocation incomplete. No attribute based selection.
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Add a mechanism to select a VME controller based on source/target type,
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required aspace, cycle and width requirements.
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struct vme_resource *vme_request_dma(struct device *dev);
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For slave windows these attributes are split into those of type ???vme_address_t???
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and ???vme_cycle_t???. Master windows add a further set of attributes ???vme_cycle_t???.
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These attributes are defined as bitmasks and as such any combination of the
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attributes can be requested for a single window, the core will assign a window
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that meets the requirements, returning a pointer of type vme_resource that
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should be used to identify the allocated resource when it is used. If an
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unallocated window fitting the requirements can not be found a NULL pointer will
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be returned.
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Functions are also provided to free window allocations once they are no longer
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required. These functions should be passed the pointer to the resource provided
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during resource allocation:
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void vme_master_free(struct vme_resource *res);
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void vme_slave_free(struct vme_resource *res);
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void vme_dma_free(struct vme_resource *res);
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Master windows
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==============
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Master windows provide access from the local processor[s] out onto the VME bus.
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The number of windows available and the available access modes is dependant on
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the underlying chipset. A window must be configured before it can be used.
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Master window configuration
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---------------------------
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Once a master window has been assigned the following functions can be used to
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configure it and retrieve the current settings:
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int vme_master_set (struct vme_resource *res, int enabled,
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unsigned long long base, unsigned long long size,
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vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
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int vme_master_get (struct vme_resource *res, int *enabled,
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unsigned long long *base, unsigned long long *size,
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vme_address_t *aspace, vme_cycle_t *cycle, vme_width_t *width);
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The address spaces, transfer widths and cycle types are the same as described
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under resource management, however some of the options are mutually exclusive.
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For example, only one address space may be specified.
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These functions return 0 on success or an error code should the call fail.
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Master window broadcast select mask
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Master window broadcast select mask
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-----------------------------------
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-----------------------------------
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TODO: Add functions to set and get Broadcast Select mask:
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API currently provides no method to set or get Broadcast Select mask. Suggest
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somthing like:
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int vme_master_bmsk_set (struct vme_resource *res, int mask);
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int vme_master_bmsk_set (struct vme_resource *res, int mask);
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int vme_master_bmsk_get (struct vme_resource *res, int *mask);
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int vme_master_bmsk_get (struct vme_resource *res, int *mask);
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Master window access
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--------------------
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The following functions can be used to read from and write to configured master
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windows. These functions return the number of bytes copied:
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ssize_t vme_master_read(struct vme_resource *res, void *buf,
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size_t count, loff_t offset);
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ssize_t vme_master_write(struct vme_resource *res, void *buf,
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size_t count, loff_t offset);
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In addition to simple reads and writes, a function is provided to do a
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read-modify-write transaction. This function returns the original value of the
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VME bus location :
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unsigned int vme_master_rmw (struct vme_resource *res,
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unsigned int mask, unsigned int compare, unsigned int swap,
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loff_t offset);
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This functions by reading the offset, applying the mask. If the bits selected in
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the mask match with the values of the corresponding bits in the compare field,
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the value of swap is written the specified offset.
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Slave windows
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=============
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Slave windows provide devices on the VME bus access into mapped portions of the
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local memory. The number of windows available and the access modes that can be
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used is dependant on the underlying chipset. A window must be configured before
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it can be used.
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Slave window configuration
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--------------------------
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Once a slave window has been assigned the following functions can be used to
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configure it and retrieve the current settings:
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int vme_slave_set (struct vme_resource *res, int enabled,
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unsigned long long base, unsigned long long size,
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dma_addr_t mem, vme_address_t aspace, vme_cycle_t cycle);
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int vme_slave_get (struct vme_resource *res, int *enabled,
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unsigned long long *base, unsigned long long *size,
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dma_addr_t *mem, vme_address_t *aspace, vme_cycle_t *cycle);
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The address spaces, transfer widths and cycle types are the same as described
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under resource management, however some of the options are mutually exclusive.
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For example, only one address space may be specified.
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These functions return 0 on success or an error code should the call fail.
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Slave window buffer allocation
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------------------------------
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Functions are provided to allow the user to allocate and free a contiguous
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buffers which will be accessible by the VME bridge. These functions do not have
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to be used, other methods can be used to allocate a buffer, though care must be
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taken to ensure that they are contiguous and accessible by the VME bridge:
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void * vme_alloc_consistent(struct vme_resource *res, size_t size,
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dma_addr_t *mem);
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void vme_free_consistent(struct vme_resource *res, size_t size,
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void *virt, dma_addr_t mem);
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Slave window access
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-------------------
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Slave windows map local memory onto the VME bus, the standard methods for
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accessing memory should be used.
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DMA channels
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============
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The VME DMA transfer provides the ability to run link-list DMA transfers. The
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API introduces the concept of DMA lists. Each DMA list is a link-list which can
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be passed to a DMA controller. Multiple lists can be created, extended,
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executed, reused and destroyed.
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List Management
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---------------
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The following functions are provided to create and destroy DMA lists. Execution
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of a list will not automatically destroy the list, thus enabling a list to be
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reused for repetitive tasks:
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struct vme_dma_list *vme_new_dma_list(struct vme_resource *res);
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int vme_dma_list_free(struct vme_dma_list *list);
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List Population
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---------------
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An item can be added to a list using the following function ( the source and
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destination attributes need to be created before calling this function, this is
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covered under "Transfer Attributes"):
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int vme_dma_list_add(struct vme_dma_list *list,
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struct vme_dma_attr *src, struct vme_dma_attr *dest,
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size_t count);
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Transfer Attributes
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-------------------
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The attributes for the source and destination are handled separately from adding
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an item to a list. This is due to the diverse attributes required for each type
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of source and destination. There are functions to create attributes for PCI, VME
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and pattern sources and destinations (where appropriate):
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Pattern source:
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struct vme_dma_attr *vme_dma_pattern_attribute(u32 pattern,
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vme_pattern_t type);
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PCI source or destination:
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struct vme_dma_attr *vme_dma_pci_attribute(dma_addr_t mem);
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VME source or destination:
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struct vme_dma_attr *vme_dma_vme_attribute(unsigned long long base,
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vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
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The following function should be used to free an attribute:
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void vme_dma_free_attribute(struct vme_dma_attr *attr);
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List Execution
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--------------
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The following function queues a list for execution. The function will return
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once the list has been executed:
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int vme_dma_list_exec(struct vme_dma_list *list);
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Interrupts
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==========
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The VME API provides functions to attach and detach callbacks to specific VME
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level and status ID combinations and for the generation of VME interrupts with
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specific VME level and status IDs.
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Attaching Interrupt Handlers
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----------------------------
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The following functions can be used to attach and free a specific VME level and
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status ID combination. Any given combination can only be assigned a single
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callback function. A void pointer parameter is provided, the value of which is
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passed to the callback function, the use of this pointer is user undefined:
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int vme_request_irq(struct device *dev, int level, int statid,
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void (*callback)(int, int, void *), void *priv);
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void vme_free_irq(struct device *dev, int level, int statid);
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The callback parameters are as follows. Care must be taken in writing a callback
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function, callback functions run in interrupt context:
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void callback(int level, int statid, void *priv);
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Interrupt Generation
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Interrupt Generation
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--------------------
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--------------------
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The following function can be used to generate a VME interrupt at a given VME
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Add optional timeout when waiting for an IACK.
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level and VME status ID:
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int vme_generate_irq(struct device *dev, int level, int statid);
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Location monitors
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CR/CSR Buffer
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=================
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-------------
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The VME API provides the following functionality to configure the location
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The VME API provides no functions to access the buffer mapped into the CR/CSR
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monitor.
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space.
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Location Monitor Management
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Mailboxes
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---------------------------
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---------
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The following functions are provided to request the use of a block of location
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Whilst not part of the VME specification, they are provided by a number of
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monitors and to free them after they are no longer required:
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chips. They are currently not supported at all by the API.
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struct vme_resource * vme_lm_request(struct device *dev);
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void vme_lm_free(struct vme_resource * res);
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Each block may provide a number of location monitors, monitoring adjacent
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locations. The following function can be used to determine how many locations
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are provided:
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int vme_lm_count(struct vme_resource * res);
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Location Monitor Configuration
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Core
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------------------------------
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====
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Once a bank of location monitors has been allocated, the following functions
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- Rename vme_master_resource's "pci_resource" to be bus agnostic.
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are provided to configure the location and mode of the location monitor:
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- Improve generic sanity checks (Such as does an offset and size fit within a
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window and parameter checking).
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int vme_lm_set(struct vme_resource *res, unsigned long long base,
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Bridge Support
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vme_address_t aspace, vme_cycle_t cycle);
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int vme_lm_get(struct vme_resource *res, unsigned long long *base,
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vme_address_t *aspace, vme_cycle_t *cycle);
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Location Monitor Use
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--------------------
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The following functions allow a callback to be attached and detached from each
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location monitor location. Each location monitor can monitor a number of
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adjacent locations:
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int vme_lm_attach(struct vme_resource *res, int num,
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void (*callback)(int));
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int vme_lm_detach(struct vme_resource *res, int num);
|
|
||||||
|
|
||||||
The callback function is declared as follows.
|
|
||||||
|
|
||||||
void callback(int num);
|
|
||||||
|
|
||||||
|
|
||||||
CR/CSR
|
|
||||||
======
|
|
||||||
|
|
||||||
TODO: The VME API needs functions to access the CR/CSR buffer.
|
|
||||||
|
|
||||||
Slot Detection
|
|
||||||
==============
|
==============
|
||||||
|
|
||||||
This function returns the slot ID of the provided bridge.
|
Tempe (tsi148)
|
||||||
|
--------------
|
||||||
|
|
||||||
|
- Driver can currently only support a single bridge.
|
||||||
|
- 2eSST Broadcast mode.
|
||||||
|
- Mailboxes unsupported.
|
||||||
|
- Improve error detection.
|
||||||
|
- Control of prefetch size, threshold.
|
||||||
|
- Arbiter control
|
||||||
|
- Requestor control
|
||||||
|
|
||||||
|
Universe II (ca91c142)
|
||||||
|
----------------------
|
||||||
|
|
||||||
|
- Driver can currently only support a single bridge.
|
||||||
|
- DMA unsupported.
|
||||||
|
- RMW transactions unsupported.
|
||||||
|
- Location Monitors unsupported.
|
||||||
|
- Mailboxes unsupported.
|
||||||
|
- Error Detection.
|
||||||
|
- Control of prefetch size, threshold.
|
||||||
|
- Arbiter control
|
||||||
|
- Requestor control
|
||||||
|
- Slot detection
|
||||||
|
|
||||||
|
Universe I (ca91x042)
|
||||||
|
---------------------
|
||||||
|
|
||||||
|
Currently completely unsupported.
|
||||||
|
|
||||||
int vme_slot_get(struct device *dev);
|
|
||||||
|
|||||||
372
drivers/staging/vme/vme_api.txt
Normal file
372
drivers/staging/vme/vme_api.txt
Normal file
@ -0,0 +1,372 @@
|
|||||||
|
VME Device Driver API
|
||||||
|
=====================
|
||||||
|
|
||||||
|
Driver registration
|
||||||
|
===================
|
||||||
|
|
||||||
|
As with other subsystems within the Linux kernel, VME device drivers register
|
||||||
|
with the VME subsystem, typically called from the devices init routine. This is
|
||||||
|
achieved via a call to the follwoing function:
|
||||||
|
|
||||||
|
int vme_register_driver (struct vme_driver *driver);
|
||||||
|
|
||||||
|
If driver registration is successful this function returns zero, if an error
|
||||||
|
occurred a negative error code will be returned.
|
||||||
|
|
||||||
|
A pointer to a structure of type 'vme_driver' must be provided to the
|
||||||
|
registration function. The structure is as follows:
|
||||||
|
|
||||||
|
struct vme_driver {
|
||||||
|
struct list_head node;
|
||||||
|
char *name;
|
||||||
|
const struct vme_device_id *bind_table;
|
||||||
|
int (*probe) (struct device *, int, int);
|
||||||
|
int (*remove) (struct device *, int, int);
|
||||||
|
void (*shutdown) (void);
|
||||||
|
struct device_driver driver;
|
||||||
|
};
|
||||||
|
|
||||||
|
At the minimum, the '.name', '.probe' and '.bind_table' elements of this
|
||||||
|
structure should be correctly set. The '.name' element is a pointer to a string
|
||||||
|
holding the device driver's name. The '.probe' element should contain a pointer
|
||||||
|
to the probe routine.
|
||||||
|
|
||||||
|
The arguments of the probe routine are as follows:
|
||||||
|
|
||||||
|
probe(struct device *dev, int bus, int slot);
|
||||||
|
|
||||||
|
The '.bind_table' is a pointer to an array of type 'vme_device_id':
|
||||||
|
|
||||||
|
struct vme_device_id {
|
||||||
|
int bus;
|
||||||
|
int slot;
|
||||||
|
};
|
||||||
|
|
||||||
|
Each structure in this array should provide a bus and slot number where the core
|
||||||
|
should probe, using the driver's probe routine, for a device on the specified
|
||||||
|
VME bus.
|
||||||
|
|
||||||
|
The VME subsystem supports a single VME driver per 'slot'. There are considered
|
||||||
|
to be 32 slots per bus, one for each slot-ID as defined in the ANSI/VITA 1-1994
|
||||||
|
specification and are analogious to the physical slots on the VME backplane.
|
||||||
|
|
||||||
|
A function is also provided to unregister the driver from the VME core and is
|
||||||
|
usually called from the device driver's exit routine:
|
||||||
|
|
||||||
|
void vme_unregister_driver (struct vme_driver *driver);
|
||||||
|
|
||||||
|
|
||||||
|
Resource management
|
||||||
|
===================
|
||||||
|
|
||||||
|
Once a driver has registered with the VME core the provided probe routine will
|
||||||
|
be called for each of the bus/slot combination that becomes valid as VME buses
|
||||||
|
are themselves registered. The probe routine is passed a pointer to the devices
|
||||||
|
device structure. This pointer should be saved, it will be required for
|
||||||
|
requesting VME resources.
|
||||||
|
|
||||||
|
The driver can request ownership of one or more master windows, slave windows
|
||||||
|
and/or dma channels. Rather than allowing the device driver to request a
|
||||||
|
specific window or DMA channel (which may be used by a different driver) this
|
||||||
|
driver allows a resource to be assigned based on the required attributes of the
|
||||||
|
driver in question:
|
||||||
|
|
||||||
|
struct vme_resource * vme_master_request(struct device *dev,
|
||||||
|
vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
|
||||||
|
|
||||||
|
struct vme_resource * vme_slave_request(struct device *dev,
|
||||||
|
vme_address_t aspace, vme_cycle_t cycle);
|
||||||
|
|
||||||
|
struct vme_resource *vme_request_dma(struct device *dev);
|
||||||
|
|
||||||
|
For slave windows these attributes are split into those of type 'vme_address_t'
|
||||||
|
and 'vme_cycle_t'. Master windows add a further set of attributes 'vme_cycle_t'.
|
||||||
|
These attributes are defined as bitmasks and as such any combination of the
|
||||||
|
attributes can be requested for a single window, the core will assign a window
|
||||||
|
that meets the requirements, returning a pointer of type vme_resource that
|
||||||
|
should be used to identify the allocated resource when it is used. If an
|
||||||
|
unallocated window fitting the requirements can not be found a NULL pointer will
|
||||||
|
be returned.
|
||||||
|
|
||||||
|
Functions are also provided to free window allocations once they are no longer
|
||||||
|
required. These functions should be passed the pointer to the resource provided
|
||||||
|
during resource allocation:
|
||||||
|
|
||||||
|
void vme_master_free(struct vme_resource *res);
|
||||||
|
|
||||||
|
void vme_slave_free(struct vme_resource *res);
|
||||||
|
|
||||||
|
void vme_dma_free(struct vme_resource *res);
|
||||||
|
|
||||||
|
|
||||||
|
Master windows
|
||||||
|
==============
|
||||||
|
|
||||||
|
Master windows provide access from the local processor[s] out onto the VME bus.
|
||||||
|
The number of windows available and the available access modes is dependant on
|
||||||
|
the underlying chipset. A window must be configured before it can be used.
|
||||||
|
|
||||||
|
|
||||||
|
Master window configuration
|
||||||
|
---------------------------
|
||||||
|
|
||||||
|
Once a master window has been assigned the following functions can be used to
|
||||||
|
configure it and retrieve the current settings:
|
||||||
|
|
||||||
|
int vme_master_set (struct vme_resource *res, int enabled,
|
||||||
|
unsigned long long base, unsigned long long size,
|
||||||
|
vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
|
||||||
|
|
||||||
|
int vme_master_get (struct vme_resource *res, int *enabled,
|
||||||
|
unsigned long long *base, unsigned long long *size,
|
||||||
|
vme_address_t *aspace, vme_cycle_t *cycle, vme_width_t *width);
|
||||||
|
|
||||||
|
The address spaces, transfer widths and cycle types are the same as described
|
||||||
|
under resource management, however some of the options are mutually exclusive.
|
||||||
|
For example, only one address space may be specified.
|
||||||
|
|
||||||
|
These functions return 0 on success or an error code should the call fail.
|
||||||
|
|
||||||
|
|
||||||
|
Master window access
|
||||||
|
--------------------
|
||||||
|
|
||||||
|
The following functions can be used to read from and write to configured master
|
||||||
|
windows. These functions return the number of bytes copied:
|
||||||
|
|
||||||
|
ssize_t vme_master_read(struct vme_resource *res, void *buf,
|
||||||
|
size_t count, loff_t offset);
|
||||||
|
|
||||||
|
ssize_t vme_master_write(struct vme_resource *res, void *buf,
|
||||||
|
size_t count, loff_t offset);
|
||||||
|
|
||||||
|
In addition to simple reads and writes, a function is provided to do a
|
||||||
|
read-modify-write transaction. This function returns the original value of the
|
||||||
|
VME bus location :
|
||||||
|
|
||||||
|
unsigned int vme_master_rmw (struct vme_resource *res,
|
||||||
|
unsigned int mask, unsigned int compare, unsigned int swap,
|
||||||
|
loff_t offset);
|
||||||
|
|
||||||
|
This functions by reading the offset, applying the mask. If the bits selected in
|
||||||
|
the mask match with the values of the corresponding bits in the compare field,
|
||||||
|
the value of swap is written the specified offset.
|
||||||
|
|
||||||
|
|
||||||
|
Slave windows
|
||||||
|
=============
|
||||||
|
|
||||||
|
Slave windows provide devices on the VME bus access into mapped portions of the
|
||||||
|
local memory. The number of windows available and the access modes that can be
|
||||||
|
used is dependant on the underlying chipset. A window must be configured before
|
||||||
|
it can be used.
|
||||||
|
|
||||||
|
|
||||||
|
Slave window configuration
|
||||||
|
--------------------------
|
||||||
|
|
||||||
|
Once a slave window has been assigned the following functions can be used to
|
||||||
|
configure it and retrieve the current settings:
|
||||||
|
|
||||||
|
int vme_slave_set (struct vme_resource *res, int enabled,
|
||||||
|
unsigned long long base, unsigned long long size,
|
||||||
|
dma_addr_t mem, vme_address_t aspace, vme_cycle_t cycle);
|
||||||
|
|
||||||
|
int vme_slave_get (struct vme_resource *res, int *enabled,
|
||||||
|
unsigned long long *base, unsigned long long *size,
|
||||||
|
dma_addr_t *mem, vme_address_t *aspace, vme_cycle_t *cycle);
|
||||||
|
|
||||||
|
The address spaces, transfer widths and cycle types are the same as described
|
||||||
|
under resource management, however some of the options are mutually exclusive.
|
||||||
|
For example, only one address space may be specified.
|
||||||
|
|
||||||
|
These functions return 0 on success or an error code should the call fail.
|
||||||
|
|
||||||
|
|
||||||
|
Slave window buffer allocation
|
||||||
|
------------------------------
|
||||||
|
|
||||||
|
Functions are provided to allow the user to allocate and free a contiguous
|
||||||
|
buffers which will be accessible by the VME bridge. These functions do not have
|
||||||
|
to be used, other methods can be used to allocate a buffer, though care must be
|
||||||
|
taken to ensure that they are contiguous and accessible by the VME bridge:
|
||||||
|
|
||||||
|
void * vme_alloc_consistent(struct vme_resource *res, size_t size,
|
||||||
|
dma_addr_t *mem);
|
||||||
|
|
||||||
|
void vme_free_consistent(struct vme_resource *res, size_t size,
|
||||||
|
void *virt, dma_addr_t mem);
|
||||||
|
|
||||||
|
|
||||||
|
Slave window access
|
||||||
|
-------------------
|
||||||
|
|
||||||
|
Slave windows map local memory onto the VME bus, the standard methods for
|
||||||
|
accessing memory should be used.
|
||||||
|
|
||||||
|
|
||||||
|
DMA channels
|
||||||
|
============
|
||||||
|
|
||||||
|
The VME DMA transfer provides the ability to run link-list DMA transfers. The
|
||||||
|
API introduces the concept of DMA lists. Each DMA list is a link-list which can
|
||||||
|
be passed to a DMA controller. Multiple lists can be created, extended,
|
||||||
|
executed, reused and destroyed.
|
||||||
|
|
||||||
|
|
||||||
|
List Management
|
||||||
|
---------------
|
||||||
|
|
||||||
|
The following functions are provided to create and destroy DMA lists. Execution
|
||||||
|
of a list will not automatically destroy the list, thus enabling a list to be
|
||||||
|
reused for repetitive tasks:
|
||||||
|
|
||||||
|
struct vme_dma_list *vme_new_dma_list(struct vme_resource *res);
|
||||||
|
|
||||||
|
int vme_dma_list_free(struct vme_dma_list *list);
|
||||||
|
|
||||||
|
|
||||||
|
List Population
|
||||||
|
---------------
|
||||||
|
|
||||||
|
An item can be added to a list using the following function ( the source and
|
||||||
|
destination attributes need to be created before calling this function, this is
|
||||||
|
covered under "Transfer Attributes"):
|
||||||
|
|
||||||
|
int vme_dma_list_add(struct vme_dma_list *list,
|
||||||
|
struct vme_dma_attr *src, struct vme_dma_attr *dest,
|
||||||
|
size_t count);
|
||||||
|
|
||||||
|
|
||||||
|
Transfer Attributes
|
||||||
|
-------------------
|
||||||
|
|
||||||
|
The attributes for the source and destination are handled separately from adding
|
||||||
|
an item to a list. This is due to the diverse attributes required for each type
|
||||||
|
of source and destination. There are functions to create attributes for PCI, VME
|
||||||
|
and pattern sources and destinations (where appropriate):
|
||||||
|
|
||||||
|
Pattern source:
|
||||||
|
|
||||||
|
struct vme_dma_attr *vme_dma_pattern_attribute(u32 pattern,
|
||||||
|
vme_pattern_t type);
|
||||||
|
|
||||||
|
PCI source or destination:
|
||||||
|
|
||||||
|
struct vme_dma_attr *vme_dma_pci_attribute(dma_addr_t mem);
|
||||||
|
|
||||||
|
VME source or destination:
|
||||||
|
|
||||||
|
struct vme_dma_attr *vme_dma_vme_attribute(unsigned long long base,
|
||||||
|
vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
|
||||||
|
|
||||||
|
The following function should be used to free an attribute:
|
||||||
|
|
||||||
|
void vme_dma_free_attribute(struct vme_dma_attr *attr);
|
||||||
|
|
||||||
|
|
||||||
|
List Execution
|
||||||
|
--------------
|
||||||
|
|
||||||
|
The following function queues a list for execution. The function will return
|
||||||
|
once the list has been executed:
|
||||||
|
|
||||||
|
int vme_dma_list_exec(struct vme_dma_list *list);
|
||||||
|
|
||||||
|
|
||||||
|
Interrupts
|
||||||
|
==========
|
||||||
|
|
||||||
|
The VME API provides functions to attach and detach callbacks to specific VME
|
||||||
|
level and status ID combinations and for the generation of VME interrupts with
|
||||||
|
specific VME level and status IDs.
|
||||||
|
|
||||||
|
|
||||||
|
Attaching Interrupt Handlers
|
||||||
|
----------------------------
|
||||||
|
|
||||||
|
The following functions can be used to attach and free a specific VME level and
|
||||||
|
status ID combination. Any given combination can only be assigned a single
|
||||||
|
callback function. A void pointer parameter is provided, the value of which is
|
||||||
|
passed to the callback function, the use of this pointer is user undefined:
|
||||||
|
|
||||||
|
int vme_request_irq(struct device *dev, int level, int statid,
|
||||||
|
void (*callback)(int, int, void *), void *priv);
|
||||||
|
|
||||||
|
void vme_free_irq(struct device *dev, int level, int statid);
|
||||||
|
|
||||||
|
The callback parameters are as follows. Care must be taken in writing a callback
|
||||||
|
function, callback functions run in interrupt context:
|
||||||
|
|
||||||
|
void callback(int level, int statid, void *priv);
|
||||||
|
|
||||||
|
|
||||||
|
Interrupt Generation
|
||||||
|
--------------------
|
||||||
|
|
||||||
|
The following function can be used to generate a VME interrupt at a given VME
|
||||||
|
level and VME status ID:
|
||||||
|
|
||||||
|
int vme_generate_irq(struct device *dev, int level, int statid);
|
||||||
|
|
||||||
|
|
||||||
|
Location monitors
|
||||||
|
=================
|
||||||
|
|
||||||
|
The VME API provides the following functionality to configure the location
|
||||||
|
monitor.
|
||||||
|
|
||||||
|
|
||||||
|
Location Monitor Management
|
||||||
|
---------------------------
|
||||||
|
|
||||||
|
The following functions are provided to request the use of a block of location
|
||||||
|
monitors and to free them after they are no longer required:
|
||||||
|
|
||||||
|
struct vme_resource * vme_lm_request(struct device *dev);
|
||||||
|
|
||||||
|
void vme_lm_free(struct vme_resource * res);
|
||||||
|
|
||||||
|
Each block may provide a number of location monitors, monitoring adjacent
|
||||||
|
locations. The following function can be used to determine how many locations
|
||||||
|
are provided:
|
||||||
|
|
||||||
|
int vme_lm_count(struct vme_resource * res);
|
||||||
|
|
||||||
|
|
||||||
|
Location Monitor Configuration
|
||||||
|
------------------------------
|
||||||
|
|
||||||
|
Once a bank of location monitors has been allocated, the following functions
|
||||||
|
are provided to configure the location and mode of the location monitor:
|
||||||
|
|
||||||
|
int vme_lm_set(struct vme_resource *res, unsigned long long base,
|
||||||
|
vme_address_t aspace, vme_cycle_t cycle);
|
||||||
|
|
||||||
|
int vme_lm_get(struct vme_resource *res, unsigned long long *base,
|
||||||
|
vme_address_t *aspace, vme_cycle_t *cycle);
|
||||||
|
|
||||||
|
|
||||||
|
Location Monitor Use
|
||||||
|
--------------------
|
||||||
|
|
||||||
|
The following functions allow a callback to be attached and detached from each
|
||||||
|
location monitor location. Each location monitor can monitor a number of
|
||||||
|
adjacent locations:
|
||||||
|
|
||||||
|
int vme_lm_attach(struct vme_resource *res, int num,
|
||||||
|
void (*callback)(int));
|
||||||
|
|
||||||
|
int vme_lm_detach(struct vme_resource *res, int num);
|
||||||
|
|
||||||
|
The callback function is declared as follows.
|
||||||
|
|
||||||
|
void callback(int num);
|
||||||
|
|
||||||
|
|
||||||
|
Slot Detection
|
||||||
|
==============
|
||||||
|
|
||||||
|
This function returns the slot ID of the provided bridge.
|
||||||
|
|
||||||
|
int vme_slot_get(struct device *dev);
|
||||||
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Reference in New Issue
Block a user