UsbHcMem.c revision 4fd606d1f5abe38e1f42c38de1d2e895166bd0f4
/** @file
Copyright (c) 2007 - 2010, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "Uhci.h"
/**
Allocate a block of memory to be used by the buffer pool.
@param Pool The buffer pool to allocate memory for.
@param Pages How many pages to allocate.
@return The allocated memory block or NULL if failed.
**/
)
{
return NULL;
}
//
// each bit in the bit array represents USBHC_MEM_UNIT
// bytes of memory in the memory block.
//
return NULL;
}
//
// Allocate the number of Pages of memory, then map it for
// bus master read and write.
//
&BufHost,
0
);
goto FREE_BITARRAY;
}
&Bytes,
);
goto FREE_BUFFER;
}
//
// Check whether the data structure used by the host controller
// should be restricted into the same 4G
//
goto FREE_BUFFER;
}
return Block;
return NULL;
}
/**
Free the memory block from the memory pool.
@param Pool The memory pool to free the block from.
@param Block The memory block to free.
**/
)
{
//
// Unmap the common buffer then free the structures
//
}
/**
Alloc some memory from the block.
@param Block The memory block to allocate memory from.
@param Units Number of memory units to allocate.
@return EFI_SUCCESS The needed memory is allocated.
@return EFI_NOT_FOUND Can't find the free memory.
**/
VOID *
)
{
StartByte = 0;
StartBit = 0;
Available = 0;
//
// If current bit is zero, the corresponding memory unit is
// available, otherwise we need to restart our searching.
// Available counts the consective number of zero bit.
//
Available++;
break;
}
} else {
Available = 0;
}
}
return NULL;
}
//
// Mark the memory as allocated
//
}
}
/**
Calculate the corresponding pci bus address according to the Mem parameter.
@param Pool The memory pool of the host controller.
@param Mem The pointer to host memory.
@param Size The size of the memory region.
@return the pci memory address
**/
)
{
return 0;
}
//
// scan the memory block list for the memory block that
// completely contains the allocated memory.
//
if ((Block->BufHost <= (UINT8 *) Mem) && (((UINT8 *) Mem + AllocSize) <= (Block->BufHost + Block->BufLen))) {
break;
}
}
//
// calculate the pci memory address for host memory address.
//
return PhyAddr;
}
/**
Insert the memory block to the pool's list of the blocks.
@param Head The head of the memory pool's block list.
@param Block The memory block to insert.
**/
)
{
}
/**
Is the memory block empty?
@param Block The memory block to check.
@return TRUE The memory block is empty.
@return FALSE The memory block isn't empty.
**/
)
{
return FALSE;
}
}
return TRUE;
}
/**
Unlink the memory block from the pool's list.
@param Head The block list head of the memory's pool.
@param BlockToUnlink The memory block to unlink.
**/
)
{
break;
}
}
}
/**
Initialize the memory management pool for the host controller.
@param PciIo The PciIo that can be used to access the host controller.
@param Check4G Whether the host controller requires allocated memory
from one 4G address space.
@param Which4G The 4G memory area each memory allocated should be from.
@return EFI_SUCCESS The memory pool is initialized.
@return EFI_OUT_OF_RESOURCE Fail to init the memory pool.
**/
)
{
return Pool;
}
}
return Pool;
}
/**
Release the memory management pool.
@param Pool The USB memory pool to free.
@return EFI_SUCCESS The memory pool is freed.
@return EFI_DEVICE_ERROR Failed to free the memory pool.
**/
)
{
//
// Unlink all the memory blocks from the pool, then free them.
// UsbHcUnlinkMemBlock can't be used to unlink and free the
// first block.
//
}
return EFI_SUCCESS;
}
/**
Allocate some memory from the host controller's memory pool
which can be used to communicate with host controller.
@param Pool The host controller's memory pool.
@param Size Size of the memory to allocate.
@return The allocated memory or NULL.
**/
VOID *
)
{
//
// First check whether current memory blocks can satisfy the allocation.
//
break;
}
}
return Mem;
}
//
// Create a new memory block if there is not enough memory
// in the pool. If the allocation size is larger than the
// default page number, just allocate a large enough memory
// block. Otherwise allocate default pages.
//
} else {
}
return NULL;
}
//
// Add the new memory block to the pool, then allocate memory from it
//
}
return Mem;
}
/**
Free the allocated memory back to the memory pool.
@param Pool The memory pool of the host controller.
@param Mem The memory to free.
@param Size The size of the memory to free.
**/
)
{
//
// scan the memory block list for the memory block that
// completely contains the memory to free.
//
//
// compute the start byte and bit in the bit array
//
//
// reset associated bits in bit arry
//
}
break;
}
}
//
// If Block == NULL, it means that the current memory isn't
// in the host controller's pool. This is critical because
// the caller has passed in a wrong memory point
//
//
// Release the current memory block if it is empty and not the head
//
}
return ;
}