docs: Update VME documentation to include kerneldoc comments
Update VME documentation given that kerneldoc comments are now provided. Add "VME API" section to VME RST to pull in kerneldoc comments. Signed-off-by: Martyn Welch <martyn.welch@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Martyn Welch
Greg Kroah-Hartman
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b5bc980a49
Коммит
48a5e6bdc2
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@ -6,36 +6,15 @@ Driver registration
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As with other subsystems within the Linux kernel, VME device drivers register
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with the VME subsystem, typically called from the devices init routine. This is
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achieved via a call to the following function:
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achieved via a call to :c:func:`vme_register_driver`.
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.. code-block:: c
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A pointer to a structure of type :c:type:`struct vme_driver <vme_driver>` must
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be provided to the registration function. Along with the maximum number of
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devices your driver is able to support.
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int vme_register_driver (struct vme_driver *driver, unsigned int ndevs);
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If driver registration is successful this function returns zero, if an error
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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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registration function. Along with ndevs, which is the number of devices your
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driver is able to support. The structure is as follows:
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.. code-block:: c
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struct vme_driver {
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struct list_head node;
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const char *name;
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int (*match)(struct vme_dev *);
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int (*probe)(struct vme_dev *);
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int (*remove)(struct vme_dev *);
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void (*shutdown)(void);
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struct device_driver driver;
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struct list_head devices;
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unsigned int ndev;
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};
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At the minimum, the '.name', '.match' and '.probe' elements of this structure
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should be correctly set. The '.name' element is a pointer to a string holding
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the device driver's name.
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At the minimum, the '.name', '.match' and '.probe' elements of
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:c:type:`struct vme_driver <vme_driver>` should be correctly set. The '.name'
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element is a pointer to a string holding the device driver's name.
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The '.match' function allows control over which VME devices should be registered
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with the driver. The match function should return 1 if a device should be
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@ -54,29 +33,16 @@ the number of devices probed to one:
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}
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The '.probe' element should contain a pointer to the probe routine. The
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probe routine is passed a 'struct vme_dev' pointer as an argument. The
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'struct vme_dev' structure looks like the following:
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.. code-block:: c
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struct vme_dev {
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int num;
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struct vme_bridge *bridge;
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struct device dev;
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struct list_head drv_list;
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struct list_head bridge_list;
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};
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probe routine is passed a :c:type:`struct vme_dev <vme_dev>` pointer as an
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argument.
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Here, the 'num' field refers to the sequential device ID for this specific
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driver. The bridge number (or bus number) can be accessed using
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dev->bridge->num.
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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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.. code-block:: c
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void vme_unregister_driver (struct vme_driver *driver);
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A function is also provided to unregister the driver from the VME core called
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:c:func:`vme_unregister_driver` and should usually be called from the device
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driver's exit routine.
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Resource management
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@ -90,47 +56,29 @@ driver is called. 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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.. code-block:: c
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struct vme_resource * vme_master_request(struct vme_dev *dev,
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u32 aspace, u32 cycle, u32 width);
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struct vme_resource * vme_slave_request(struct vme_dev *dev, u32 aspace,
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u32 cycle);
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struct vme_resource *vme_dma_request(struct vme_dev *dev, u32 route);
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For slave windows these attributes are split into the VME address spaces that
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need to be accessed in 'aspace' and VME bus cycle types required in 'cycle'.
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Master windows add a further set of attributes in 'width' specifying the
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required data transfer widths. These attributes are defined as bitmasks and as
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such any combination of the attributes can be requested for a single window,
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the core will assign a window that meets the requirements, returning a pointer
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of type vme_resource that should be used to identify the allocated resource
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when it is used. For DMA controllers, the request function requires the
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potential direction of any transfers to be provided in the route attributes.
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This is typically VME-to-MEM and/or MEM-to-VME, though some hardware can
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support VME-to-VME and MEM-to-MEM transfers as well as test pattern generation.
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If an unallocated window fitting the requirements can not be found a NULL
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pointer will be returned.
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The driver can request ownership of one or more master windows
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(:c:func:`vme_master_request`), slave windows (:c:func:`vme_slave_request`)
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and/or dma channels (:c:func:`vme_dma_request`). Rather than allowing the device
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driver to request a specific window or DMA channel (which may be used by a
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different driver) the API allows a resource to be assigned based on the required
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attributes of the driver in question. For slave windows these attributes are
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split into the VME address spaces that need to be accessed in 'aspace' and VME
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bus cycle types required in 'cycle'. Master windows add a further set of
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attributes in 'width' specifying the required data transfer widths. These
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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. For DMA
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controllers, the request function requires the potential direction of any
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transfers to be provided in the route attributes. This is typically VME-to-MEM
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and/or MEM-to-VME, though some hardware can support VME-to-VME and MEM-to-MEM
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transfers as well as test pattern generation. If an unallocated window fitting
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the requirements can not be found a NULL pointer will 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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.. code-block:: c
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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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required. These functions (:c:func:`vme_master_free`, :c:func:`vme_slave_free`
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and :c:func:`vme_dma_free`) should be passed the pointer to the resource
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provided during resource allocation.
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Master windows
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@ -144,61 +92,22 @@ 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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.. code-block:: c
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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, u32 aspace,
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u32 cycle, u32 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, u32 *aspace,
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u32 *cycle, u32 *width);
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The address spaces, transfer widths and cycle types are the same as described
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Once a master window has been assigned :c:func:`vme_master_set` can be used to
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configure it and :c:func:`vme_master_get` to retrieve the current settings. The
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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 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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The function :c:func:`vme_master_read` can be used to read from and
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:c:func:`vme_master_write` used to write to configured master windows.
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.. code-block:: c
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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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.. code-block:: c
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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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Parts of a VME window can be mapped into user space memory using the following
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function:
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.. code-block:: c
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int vme_master_mmap(struct vme_resource *resource,
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struct vm_area_struct *vma)
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In addition to simple reads and writes, :c:func:`vme_master_rmw` is provided to
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do a read-modify-write transaction. Parts of a VME window can also be mapped
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into user space memory using :c:func:`vme_master_mmap`.
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Slave windows
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@ -213,41 +122,23 @@ 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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.. code-block:: c
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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, u32 aspace, u32 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, u32 *aspace, u32 *cycle);
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Once a slave window has been assigned :c:func:`vme_slave_set` can be used to
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configure it and :c:func:`vme_slave_get` to retrieve the current settings.
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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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.. code-block:: c
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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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Functions are provided to allow the user to allocate
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(:c:func:`vme_alloc_consistent`) and free (:c:func:`vme_free_consistent`)
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contiguous buffers which will be accessible by the VME bridge. These functions
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do not have to be used, other methods can be used to allocate a buffer, though
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care must be taken to ensure that they are contiguous and accessible by the VME
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bridge.
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Slave window access
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@ -269,29 +160,18 @@ 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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.. code-block:: c
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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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The function :c:func:`vme_new_dma_list` is provided to create and
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:c:func:`vme_dma_list_free` to destroy DMA lists. Execution of a list will not
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automatically destroy the list, thus enabling a list to be reused for repetitive
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tasks.
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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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An item can be added to a list using :c:func:`vme_dma_list_add` (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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.. code-block:: c
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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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covered under "Transfer Attributes").
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.. note::
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@ -310,41 +190,19 @@ 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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- PCI source or destination: :c:func:`vme_dma_pci_attribute`
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- VME source or destination: :c:func:`vme_dma_vme_attribute`
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- Pattern source: :c:func:`vme_dma_pattern_attribute`
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.. code-block:: c
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struct vme_dma_attr *vme_dma_pattern_attribute(u32 pattern, u32 type);
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PCI source or destination:
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.. code-block:: c
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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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.. code-block:: c
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struct vme_dma_attr *vme_dma_vme_attribute(unsigned long long base,
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u32 aspace, u32 cycle, u32 width);
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The following function should be used to free an attribute:
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.. code-block:: c
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void vme_dma_free_attribute(struct vme_dma_attr *attr);
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The function :c:func:`vme_dma_free_attribute` should be used to free an
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attribute.
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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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.. code-block:: c
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int vme_dma_list_exec(struct vme_dma_list *list);
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The function :c:func:`vme_dma_list_exec` queues a list for execution and will
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return once the list has been executed.
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Interrupts
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@ -358,20 +216,13 @@ 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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.. code-block:: c
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int vme_irq_request(struct vme_dev *dev, int level, int statid,
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void (*callback)(int, int, void *), void *priv);
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void vme_irq_free(struct vme_dev *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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The function :c:func:`vme_irq_request` can be used to attach and
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:c:func:`vme_irq_free` to free a specific VME level and status ID combination.
|
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Any given combination can only be assigned a single callback function. A void
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pointer parameter is provided, the value of which is passed to the callback
|
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function, the use of this pointer is user undefined. The callback parameters are
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as follows. Care must be taken in writing a callback function, callback
|
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functions run in interrupt context:
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.. code-block:: c
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@ -381,12 +232,8 @@ function, callback functions run in interrupt context:
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Interrupt Generation
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~~~~~~~~~~~~~~~~~~~~
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The following function can be used to generate a VME interrupt at a given VME
|
||||
level and VME status ID:
|
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.. code-block:: c
|
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int vme_irq_generate(struct vme_dev *dev, int level, int statid);
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The function :c:func:`vme_irq_generate` can be used to generate a VME interrupt
|
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at a given VME level and VME status ID.
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Location monitors
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@ -399,54 +246,29 @@ monitor.
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Location Monitor Management
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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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monitors and to free them after they are no longer required:
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.. code-block:: c
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struct vme_resource * vme_lm_request(struct vme_dev *dev);
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void vme_lm_free(struct vme_resource * res);
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|
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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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.. code-block:: c
|
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int vme_lm_count(struct vme_resource * res);
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||||
The function :c:func:`vme_lm_request` is provided to request the use of a block
|
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of location monitors and :c:func:`vme_lm_free` to free them after they are no
|
||||
longer required. Each block may provide a number of location monitors,
|
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monitoring adjacent locations. The function :c:func:`vme_lm_count` can be used
|
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to determine how many locations are provided.
|
||||
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||||
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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:
|
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.. code-block:: c
|
||||
|
||||
int vme_lm_set(struct vme_resource *res, unsigned long long base,
|
||||
u32 aspace, u32 cycle);
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||||
|
||||
int vme_lm_get(struct vme_resource *res, unsigned long long *base,
|
||||
u32 *aspace, u32 *cycle);
|
||||
Once a bank of location monitors has been allocated, the function
|
||||
:c:func:`vme_lm_set` is provided to configure the location and mode of the
|
||||
location monitor. The function :c:func:`vme_lm_get` can be used to retrieve
|
||||
existing settings.
|
||||
|
||||
|
||||
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:
|
||||
|
||||
.. code-block:: c
|
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|
||||
int vme_lm_attach(struct vme_resource *res, int num,
|
||||
void (*callback)(void *));
|
||||
|
||||
int vme_lm_detach(struct vme_resource *res, int num);
|
||||
|
||||
The callback function is declared as follows.
|
||||
The function :c:func:`vme_lm_attach` enables a callback to be attached and
|
||||
:c:func:`vme_lm_detach` allows on to be detached from each location monitor
|
||||
location. Each location monitor can monitor a number of adjacent locations. The
|
||||
callback function is declared as follows.
|
||||
|
||||
.. code-block:: c
|
||||
|
||||
|
|
@ -456,19 +278,20 @@ The callback function is declared as follows.
|
|||
Slot Detection
|
||||
--------------
|
||||
|
||||
This function returns the slot ID of the provided bridge.
|
||||
|
||||
.. code-block:: c
|
||||
|
||||
int vme_slot_num(struct vme_dev *dev);
|
||||
The function :c:func:`vme_slot_num` returns the slot ID of the provided bridge.
|
||||
|
||||
|
||||
Bus Detection
|
||||
-------------
|
||||
|
||||
This function returns the bus ID of the provided bridge.
|
||||
The function :c:func:`vme_bus_num` returns the bus ID of the provided bridge.
|
||||
|
||||
.. code-block:: c
|
||||
|
||||
int vme_bus_num(struct vme_dev *dev);
|
||||
VME API
|
||||
-------
|
||||
|
||||
.. kernel-doc:: include/linux/vme.h
|
||||
:internal:
|
||||
|
||||
.. kernel-doc:: drivers/vme/vme.c
|
||||
:export:
|
||||
|
|
|
|||
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