EMILE/second/MMU040.c
2005-06-06 19:38:07 +00:00

183 lines
3.8 KiB
C

/*
*
* (c) 2004,2005 Laurent Vivier <LaurentVivier@wanadoo.fr>
*
* a lot of parts from penguin booter
*/
#include <stdio.h>
#include "console.h"
#include "MMU040.h"
#define GET_TC_ENABLE(TC) (TC & 0x8000)
#define IS_8K_PAGE(TC) (TC & 0x4000)
#define GET_TC_PAGE_SIZE(TC) (IS_8K_PAGE(TC) ? 8192 : 4096)
#define GET_PDT(PDT) (PDT&3)
#define UDT_IS_INVALID(PDT) (GET_PDT(PDT) == 0)
#define UDT_IS_RESIDENT(PDT) ((GET_PDT(PDT) == 1) || (GET_PDT(PDT) == 3))
#define UDT_IS_INDIRECT(PDT) (GET_PDT(PDT) == 2)
#define GET_RP_UDT(RP) (RP & 0x00000003)
#define GET_RP_W(RP) (RP & 0x00000004)
#define GET_RP_U(RP) (RP & 0x00000008)
#define GET_RP_ADDR(RP) (RP & 0xFFFFFE00)
#define GET_TD_4K_ADDR(TD) (TD & 0xFFFFFF00)
#define GET_TD_8K_ADDR(TD) (TD & 0xFFFFFF80)
#define GET_TT_ENABLE(TT) (TT & 0x8000)
#define GET_TT_BASE(TT) ( (TT >> 24) & 0xFF )
#define GET_TT_MASK(TT) ( (TT >> 16) & 0xFF )
#ifdef TRACE_MMU
#define TRACE(format, args...) if (MMU_trace) printf(format, ##args)
static int MMU_trace = 0;
void MMU040_set_trace(int enable)
{
MMU_trace = enable;
}
#else
#define TRACE(format, args...)
#endif
static int isTTSegment(unsigned long addr)
{
unsigned long DTT0;
unsigned long DTT1;
unsigned long base;
unsigned long mask;
unsigned long size;
addr >>= 24;
MMU040_get_DTT0(&DTT0);
if (GET_TT_ENABLE(DTT0))
{
mask = GET_TT_MASK(DTT0);
base = GET_TT_BASE(DTT0);
base &= ~mask;
addr &= ~mask;
size = mask & 0x000000FF;
if ( (base <= addr) && (addr <= base + size) )
return 1;
}
MMU040_get_DTT1(&DTT1);
if (GET_TT_ENABLE(DTT1))
{
mask = GET_TT_MASK(DTT1);
base = GET_TT_BASE(DTT1);
base &= ~mask;
addr &= ~mask;
size = mask & 0x000000FF;
if ( (base <= addr) && (addr <= base + size) )
return 1;
}
/* if come here : no Transparent Translation */
return 0;
}
int MMU040_logical2physicalAttr(unsigned long logicalAddr, unsigned long *physicalAddr, unsigned long *attr)
{
unsigned long TC;
int rootIndex, ptrIndex, pageIndex;
unsigned long pageOffst;
unsigned long rootTable, ptrTable, pageTable;
unsigned long rootEntry, tableEntry, pageEntry;
TRACE("logical: %08lx ", logicalAddr);
MMU040_get_TC(&TC);
TRACE("TC: %08lx\n", TC);
if ( !GET_TC_ENABLE(TC) || isTTSegment(logicalAddr) )
{
*physicalAddr = logicalAddr;
return 0;
}
MMU040_get_SRP(&rootTable);
TRACE("SRP: %ld\n", rootTable);
rootIndex = (logicalAddr & 0xFE000000) >> 25;
rootEntry = MMU040_read_phys(rootTable + 4 * rootIndex);
TRACE("Root Entry: %08lx\n", rootEntry);
if ( UDT_IS_INVALID(rootEntry) || UDT_IS_RESIDENT(rootEntry) )
{
*physicalAddr = logicalAddr;
return 0;
}
ptrTable = GET_RP_ADDR(rootEntry);
ptrIndex = (logicalAddr & 0x01FC0000) >> 18;
tableEntry = MMU040_read_phys(ptrTable + 4 * ptrIndex);
TRACE("table Entry: %08lx\n", tableEntry);
if ( UDT_IS_INVALID(tableEntry) || UDT_IS_RESIDENT(tableEntry) )
{
*physicalAddr = logicalAddr;
return 0;
}
if (IS_8K_PAGE(TC))
{
pageTable = GET_TD_8K_ADDR(tableEntry);
pageIndex = (logicalAddr & 0x0003E000) >> 13;
pageEntry = MMU040_read_phys(pageTable + 4 * pageIndex);
pageOffst = logicalAddr & 0x00001FFF;
*physicalAddr = (pageEntry & 0xFFFFE000) + pageOffst;
}
else
{
pageTable = GET_TD_4K_ADDR(tableEntry);
pageIndex = (logicalAddr & 0x0003F000) >> 12;
pageEntry = MMU040_read_phys(pageTable + 4 * pageIndex);
pageOffst = logicalAddr & 0x00000FFF;
*physicalAddr = (pageEntry & 0xFFFFF000) + pageOffst;
}
*attr = pageEntry & 0x000004FF;
TRACE("physical: %08lx\n", *physicalAddr);
return 0;
}
int MMU040_logical2physical(unsigned long logicalAddr, unsigned long *physicalAddr)
{
unsigned long attr;
return MMU040_logical2physicalAttr(logicalAddr, physicalAddr, &attr);
}
unsigned long MMU040_get_page_size(void)
{
unsigned long TC;
MMU040_get_TC(&TC);
TRACE("Page Size: %d\n", GET_TC_PAGE_SIZE(TC));
return GET_TC_PAGE_SIZE(TC);
}