71 lines
1.5 KiB
C
71 lines
1.5 KiB
C
#include "io.h"
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#include "heap.h"
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#include "load_buffer.h"
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/*
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* Initialise a buffer in an unused portion of memory, to be used for
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* loading an image
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*
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*/
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#ifdef KEEP_IT_REAL
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/*
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* Under KEEP_IT_REAL, always use 07c0:0000 as the load buffer.
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*
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*/
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int init_load_buffer ( struct buffer *buffer ) {
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buffer->start = 0x7c00;
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buffer->end = 0xa0000;
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DBG ( "LOAD_BUFFER using [%x,%x)\n", buffer->start, buffer->end );
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init_buffer ( buffer );
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return 1;
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}
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void trim_load_buffer ( struct buffer *buffer ) {
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/* Nothing to do */
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}
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void done_load_buffer ( struct buffer *buffer ) {
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/* Nothing to do */
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}
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#else /* KEEP_IT_REAL */
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/*
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* Without KEEP_IT_REAL, use all remaining heap space as the load buffer.
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*
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*/
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int init_load_buffer ( struct buffer *buffer ) {
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void *data;
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size_t size;
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data = emalloc_all ( &size );
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if ( ! data )
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return 0;
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buffer->start = virt_to_phys ( data );
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buffer->end = buffer->start + size;
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DBG ( "LOAD_BUFFER using [%x,%x)\n", buffer->start, buffer->end );
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init_buffer ( buffer );
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return 1;
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}
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void trim_load_buffer ( struct buffer *buffer ) {
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void *new_start;
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/* Shrink buffer */
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new_start = erealloc ( phys_to_virt ( buffer->start ), buffer->fill );
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DBG ( "LOAD_BUFFER shrunk from [%x,%x) to [%x,%x)\n", buffer->start,
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buffer->end, virt_to_phys ( new_start ), buffer->end );
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buffer->start = virt_to_phys ( new_start );
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}
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void done_load_buffer ( struct buffer *buffer ) {
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efree ( phys_to_virt ( buffer->start ) );
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DBG ( "LOAD_BUFFER freed [%x,%x)\n", buffer->start, buffer->end );
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}
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#endif
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