diff options
Diffstat (limited to 'gpxe/src/arch/i386/core/relocate.c')
| -rw-r--r-- | gpxe/src/arch/i386/core/relocate.c | 170 |
1 files changed, 0 insertions, 170 deletions
diff --git a/gpxe/src/arch/i386/core/relocate.c b/gpxe/src/arch/i386/core/relocate.c deleted file mode 100644 index 44e764fe..00000000 --- a/gpxe/src/arch/i386/core/relocate.c +++ /dev/null @@ -1,170 +0,0 @@ -#include <gpxe/io.h> -#include <registers.h> -#include <gpxe/memmap.h> - -/* - * Originally by Eric Biederman - * - * Heavily modified by Michael Brown - * - */ - -FILE_LICENCE ( GPL2_OR_LATER ); - -/* - * The linker passes in the symbol _max_align, which is the alignment - * that we must preserve, in bytes. - * - */ -extern char _max_align[]; -#define max_align ( ( unsigned int ) _max_align ) - -/* Linker symbols */ -extern char _textdata[]; -extern char _etextdata[]; - -/* within 1MB of 4GB is too close. - * MAX_ADDR is the maximum address we can easily do DMA to. - * - * Not sure where this constraint comes from, but kept it from Eric's - * old code - mcb30 - */ -#define MAX_ADDR (0xfff00000UL) - -/** - * Relocate Etherboot - * - * @v ix86 x86 register dump from prefix - * @ret ix86 x86 registers to return to prefix - * - * This finds a suitable location for Etherboot near the top of 32-bit - * address space, and returns the physical address of the new location - * to the prefix in %edi. - */ -__asmcall void relocate ( struct i386_all_regs *ix86 ) { - struct memory_map memmap; - unsigned long start, end, size, padded_size; - unsigned long new_start, new_end; - unsigned i; - - /* Get memory map and current location */ - get_memmap ( &memmap ); - start = virt_to_phys ( _textdata ); - end = virt_to_phys ( _etextdata ); - size = ( end - start ); - padded_size = ( size + max_align - 1 ); - - DBG ( "Relocate: currently at [%lx,%lx)\n" - "...need %lx bytes for %d-byte alignment\n", - start, end, padded_size, max_align ); - - /* Walk through the memory map and find the highest address - * below 4GB that etherboot will fit into. Ensure etherboot - * lies entirely within a range with A20=0. This means that - * even if something screws up the state of the A20 line, the - * etherboot code is still visible and we have a chance to - * diagnose the problem. - */ - new_end = end; - for ( i = 0 ; i < memmap.count ; i++ ) { - struct memory_region *region = &memmap.regions[i]; - unsigned long r_start, r_end; - - DBG ( "Considering [%llx,%llx)\n", region->start, region->end); - - /* Truncate block to MAX_ADDR. This will be less than - * 4GB, which means that we can get away with using - * just 32-bit arithmetic after this stage. - */ - if ( region->start > MAX_ADDR ) { - DBG ( "...starts after MAX_ADDR=%lx\n", MAX_ADDR ); - continue; - } - r_start = region->start; - if ( region->end > MAX_ADDR ) { - DBG ( "...end truncated to MAX_ADDR=%lx\n", MAX_ADDR ); - r_end = MAX_ADDR; - } else { - r_end = region->end; - } - - /* Shrink the range down to use only even megabytes - * (i.e. A20=0). - */ - if ( ( r_end - 1 ) & 0x100000 ) { - /* If last byte that might be used (r_end-1) - * is in an odd megabyte, round down r_end to - * the top of the next even megabyte. - * - * Make sure that we don't accidentally wrap - * r_end below 0. - */ - if ( r_end >= 1 ) { - r_end = ( r_end - 1 ) & ~0xfffff; - DBG ( "...end truncated to %lx " - "(avoid ending in odd megabyte)\n", - r_end ); - } - } else if ( ( r_end - size ) & 0x100000 ) { - /* If the last byte that might be used - * (r_end-1) is in an even megabyte, but the - * first byte that might be used (r_end-size) - * is an odd megabyte, round down to the top - * of the next even megabyte. - * - * Make sure that we don't accidentally wrap - * r_end below 0. - */ - if ( r_end >= 0x100000 ) { - r_end = ( r_end - 0x100000 ) & ~0xfffff; - DBG ( "...end truncated to %lx " - "(avoid starting in odd megabyte)\n", - r_end ); - } - } - - DBG ( "...usable portion is [%lx,%lx)\n", r_start, r_end ); - - /* If we have rounded down r_end below r_ start, skip - * this block. - */ - if ( r_end < r_start ) { - DBG ( "...truncated to negative size\n" ); - continue; - } - - /* Check that there is enough space to fit in Etherboot */ - if ( ( r_end - r_start ) < size ) { - DBG ( "...too small (need %lx bytes)\n", size ); - continue; - } - - /* If the start address of the Etherboot we would - * place in this block is higher than the end address - * of the current highest block, use this block. - * - * Note that this avoids overlaps with the current - * Etherboot, as well as choosing the highest of all - * viable blocks. - */ - if ( ( r_end - size ) > new_end ) { - new_end = r_end; - DBG ( "...new best block found.\n" ); - } - } - - /* Calculate new location of Etherboot, and align it to the - * required alignemnt. - */ - new_start = new_end - padded_size; - new_start += ( start - new_start ) & ( max_align - 1 ); - new_end = new_start + size; - - DBG ( "Relocating from [%lx,%lx) to [%lx,%lx)\n", - start, end, new_start, new_end ); - - /* Let prefix know what to copy */ - ix86->regs.esi = start; - ix86->regs.edi = new_start; - ix86->regs.ecx = size; -} |