|
|
How to drive a LCD on ARM based linux System
12-18-2007
How to drive a LCD on ARM based linux System
,|
|
hat_getkpfnum(9F) Kernel Functions for Drivers hat_getkpfnum(9F) NAME
hat_getkpfnum - get page frame number for kernel address SYNOPSIS
#include <sys/types.h> #include <sys/ddi.h> #include <sys/sunddi.h> pfn_t hat_getkpfnum(caddr_t addr); INTERFACE LEVEL
This interface is obsolete. A driver devmap(9E) entry point should be provided instead. PARAMETERS
addr The kernel virtual address for which the page frame number is to be returned. DESCRIPTION
hat_getkpfnum() returns the page frame number corresponding to the kernel virtual address, addr. addr must be a kernel virtual address which maps to device memory. ddi_map_regs(9F) can be used to obtain this address. For example, ddi_map_regs(9F) can be called in the driver's attach(9E) routine. The resulting kernel virtual address can be saved by the driver (see ddi_soft_state(9F)) and used in mmap(9E). The corresponding ddi_unmap_regs(9F) call can be made in the driver's detach(9E) routine. Refer to mmap(9E) for more information. RETURN VALUES
The page frame number corresponding to the valid, device-mapped virtual address addr. Otherwise the return value is undefined. CONTEXT
hat_getkpfnum() can be called only from user or kernel context. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface stability |Obsolete | +-----------------------------+-----------------------------+ SEE ALSO
attach(9E), detach(9E), devmap(9E), mmap(9E), ddi_map_regs(9F), ddi_soft_state(9F), ddi_unmap_regs(9F) Writing Device Drivers NOTES
For some devices, mapping device memory in the driver's attach(9E) routine and unmapping device memory in the driver's detach(9E) routine is a sizeable drain on system resources. This is especially true for devices with a large amount of physical address space. Refer to mmap(9E) for alternative methods. SunOS 5.11 13 June 2004 hat_getkpfnum(9F)