|DEVMAP_DEVMEM_SETUP(9F)||Kernel Functions for Drivers||DEVMAP_DEVMEM_SETUP(9F)|
#include <sys/ddi.h> #include <sys/sunddi.h> int devmap_devmem_setup(devmap_cookie_t dhp, dev_info_t *dip, struct devmap_callback_ctl *callbackops, uint_t rnumber, offset_t roff, size_t len, uint_t maxprot, uint_t flags, ddi_device_acc_attr_t *accattrp);
int devmap_umem_setup(devmap_cookie_t dhp, dev_info_t *dip, struct devmap_callback_ctl *callbackops, ddi_umem_cookie_t cookie, offset_t koff, size_t len, uint_t maxprot, uint_t flags, ddi_device_acc_attr_t *accattrp);
Possible values of the cache attribute are:
If IOMEM_DATA_UC_WR_COMBINE is specified but not supported, IOMEM_DATA_UNCACHED is used instead.
The cache attributes are mutually exclusive. Any combination of the values leads to a failure. On the SPARC architecture, only IOMEM_DATA_CACHED is meaningful. Others lead to a failure.
The dhp argument specifies a device mapping handle that the system uses to store all mapping parameters of a physical contiguous memory. The system copies the data pointed to by callbackops to a system private memory. This allows the driver to free the data after returning from either devmap_devmem_setup() or devmap_umem_setup(). The driver is notified of user events on the mappings via the entry points defined by devmap_callback_ctl(9S). The driver is notified of the following user events:
By specifying a valid callbackops to the system, device drivers can manage events on a device mapping. For example, the devmap_access(9E) entry point allows the drivers to perform context switching by unloading the mappings of other processes and to load the mapping of the calling process. Device drivers may specify NULL to callbackops which means the drivers do not want to be notified by the system.
The maximum protection allowed for the mapping is specified in maxprot. accattrp defines the device access attributes. See ddi_device_acc_attr(9S) for more details.
devmap_devmem_setup() is used for device memory to map in the register set given by rnumber and the offset into the register address space given by roff. The system uses rnumber and roff to go up the device tree to get the physical address that corresponds to roff. The range to be affected is defined by len and roff. The range from roff to roff + len must be a physical contiguous memory and page aligned.
Drivers use devmap_umem_setup() for kernel memory to map in the kernel memory described by cookie and the offset into the kernel memory space given by koff. cookie is a kernel memory pointer obtained from ddi_umem_alloc(9F). If cookie is NULL, devmap_umem_setup() returns -1. The range to be affected is defined by len and koff. The range from koff to koff + len must be within the limits of the kernel memory described by koff + len and must be page aligned.
Drivers use devmap_umem_setup() to export the kernel memory allocated by ddi_umem_alloc(9F) to user space. The system selects a user virtual address that is aligned with the kernel virtual address being mapped to avoid cache incoherence if the mapping is not MAP_FIXED.
Writing Device Drivers
|June 5, 2006||OmniOS|