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fe7075dfa5bc5f487e25e22e1137b9abd7a9f9a1
FireBee_SVN/sys/mmu.c
Markus Fröschle d860191121 replaced DMA API routines by fresh download with originals 
moved more interrupt handlers to generalized handler
cleaned up lowlevel interrupt handling
fixed wrong assignment of interrupt masks
reformatted
2015-01-11 10:27:36 +00:00

984 lines
31 KiB
C
Raw Blame History

#include "mmu.h"
#include "acia.h"
#include "exceptions.h"
#if defined(MACHINE_FIREBEE)
#include "firebee.h"
#elif defined(MACHINE_M5484LITE)
#include "m5484l.h"
#elif defined(MACHINE_M54455)
#include "m54455.h"
#else
#error "unknown machine!"
#endif
/*
* mmu.c
*
* This file is part of BaS_gcc.
*
* BaS_gcc is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* BaS_gcc is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with BaS_gcc. If not, see <http://www.gnu.org/licenses/>.
*
* derived from original assembler sources:
* Copyright 2010 - 2012 F. Aschwanden
* Copyright 2013 M. Froeschle
*/
#define ACR_BA(x) ((x) & 0xffff0000)
#define ACR_ADMSK(x) (((x) & 0xffff) << 16)
#define ACR_E(x) (((x) & 1) << 15)
#define ACR_S(x) (((x) & 3) << 13)
#define ACR_S_USERMODE 0
#define ACR_S_SUPERVISOR_MODE 1
#define ACR_S_ALL 2
#define ACR_AMM(x) (((x) & 1) << 10)
#define ACR_CM(x) (((x) & 3) << 5)
#define ACR_CM_CACHEABLE_WT 0x0
#define ACR_CM_CACHEABLE_CB 0x1
#define ACR_CM_CACHE_INH_PRECISE 0x2
#define ACR_CM_CACHE_INH_IMPRECISE 0x3
#define ACR_SP(x) (((x) & 1) << 3)
#define ACR_W(x) (((x) & 1) << 2)
#include <stdint.h>
#include "bas_printf.h"
#include "bas_types.h"
#include "MCF5475.h"
#include "pci.h"
#include "cache.h"
#include "util.h"
#if defined(MACHINE_FIREBEE)
#include "firebee.h"
#elif defined(MACHINE_M5484LITE)
#include "m5484l.h"
#elif defined(MACHINE_M54455)
#include "m54455.h"
#else
#error "unknown machine!"x
#endif /* MACHINE_FIREBEE */
//#define DBG_MMU
#ifdef DBG_MMU
#define dbg(format, arg...) do { xprintf("DEBUG (%s()): " format, __FUNCTION__, ##arg);} while(0)
#else
#define dbg(format, arg...) do {;} while (0)
#endif /* DBG_MMU */
#define err(format, arg...) do { xprintf("ERROR (%s()): " format, __FUNCTION__, ##arg); } while(0);
/*
* set ASID register
* saves new value to rt_asid and returns former value
*/
inline uint32_t set_asid(uint32_t value)
{
extern long rt_asid;
uint32_t ret = rt_asid;
__asm__ __volatile__(
"movec %[value],ASID\n\t"
: /* no output */
: [value] "r" (value)
:
);
rt_asid = value;
return ret;
}
/*
* set ACRx register
* saves new value to rt_acrx and returns former value
*/
inline uint32_t set_acr0(uint32_t value)
{
extern uint32_t rt_acr0;
uint32_t ret = rt_acr0;
__asm__ __volatile__(
"movec %[value],ACR0\n\t"
: /* not output */
: [value] "r" (value)
:
);
rt_acr0 = value;
return ret;
}
/*
* set ACRx register
* saves new value to rt_acrx and returns former value
*/
inline uint32_t set_acr1(uint32_t value)
{
extern uint32_t rt_acr1;
uint32_t ret = rt_acr1;
__asm__ __volatile__(
"movec %[value],ACR1\n\t"
: /* not output */
: [value] "r" (value)
:
);
rt_acr1 = value;
return ret;
}
/*
* set ACRx register
* saves new value to rt_acrx and returns former value
*/
inline uint32_t set_acr2(uint32_t value)
{
extern uint32_t rt_acr2;
uint32_t ret = rt_acr2;
__asm__ __volatile__(
"movec %[value],ACR2\n\t"
: /* not output */
: [value] "r" (value)
:
);
rt_acr2 = value;
return ret;
}
/*
* set ACRx register
* saves new value to rt_acrx and returns former value
*/
inline uint32_t set_acr3(uint32_t value)
{
extern uint32_t rt_acr3;
uint32_t ret = rt_acr3;
__asm__ __volatile__(
"movec %[value],ACR3\n\t"
: /* not output */
: [value] "r" (value)
:
);
rt_acr3 = value;
return ret;
}
inline uint32_t set_mmubar(uint32_t value)
{
extern uint32_t rt_mmubar;
uint32_t ret = rt_mmubar;
__asm__ __volatile__(
"movec %[value],MMUBAR\n\t"
: /* no output */
: [value] "r" (value)
: /* no clobber */
);
rt_mmubar = value;
NOP();
return ret;
}
/*
* translation table for virtual address ranges. Holds the physical_offset (which must be added to a virtual
* address to get its physical counterpart) for memory ranges.
*/
struct virt_to_phys
{
uint32_t start_address;
uint32_t length;
uint32_t physical_offset;
};
#if defined(MACHINE_FIREBEE)
static struct virt_to_phys translation[] =
{
/* virtual , length , offset */
{ 0x00000000, 0x00e00000, 0x60000000 }, /* map first 14 MByte to first 14 Mb of video ram */
{ 0x00e00000, 0x00100000, 0x00000000 }, /* map TOS to SDRAM */
{ 0x00f00000, 0x00100000, 0xff000000 }, /* map Falcon I/O area to FPGA */
{ 0x01000000, 0x1f000000, 0x00000000 }, /* map rest of ram virt = phys */
};
#elif defined(MACHINE_M5484LITE)
static struct virt_to_phys translation[] =
{
/* virtual , length , offset */
{ 0x00000000, 0x00e00000, 0x00000000 }, /* map first 14 MByte to first 14 Mb of SD ram */
{ 0x00e00000, 0x00100000, 0x00000000 }, /* map TOS to SDRAM */
{ 0x01000000, 0x04000000, 0x00000000 }, /* map rest of ram virt = phys */
{ 0x60000000, 0x10000000, 0x00000000 }, /* map CPLD CF card I/O area */
};
#elif defined(MACHINE_M54455)
/* FIXME: this is not determined yet! */
static struct virt_to_phys translation[] =
{
/* virtual , length , offset */
{ 0x00000000, 0x00e00000, 0x60000000 }, /* map first 14 MByte to first 14 Mb of video ram */
{ 0x00e00000, 0x00100000, 0x00000000 }, /* map TOS to SDRAM */
{ 0x00f00000, 0x00100000, 0xff000000 }, /* map Falcon I/O area to FPGA */
{ 0x01000000, 0x1f000000, 0x00000000 }, /* map rest of ram virt = phys */
};
#else
#error unknown machine!
#endif
static int num_translations = sizeof(translation) / sizeof(struct virt_to_phys);
static inline int32_t lookup_phys(int32_t virt)
{
int i;
for (i = 0; i < num_translations; i++)
{
if (virt >= translation[i].start_address && virt < translation[i].start_address + translation[i].length)
{
return virt + translation[i].physical_offset;
}
}
err("virtual address 0x%lx not found in translation table!\r\n", virt);
return -1;
}
struct page_descriptor
{
uint8_t cache_mode : 2;
uint8_t supervisor_protect : 1;
uint8_t read : 1;
uint8_t write : 1;
uint8_t execute : 1;
uint8_t global : 1;
uint8_t locked : 1;
};
/*
* page descriptors. Size depending on DEFAULT_PAGE_SIZE, either 1M (resulting in 512
* bytes size) or 8k pages (64k descriptor array size)
*/
static struct page_descriptor pages[SDRAM_SIZE / DEFAULT_PAGE_SIZE];
int mmu_map_instruction_page(int32_t virt, uint8_t asid)
{
const uint32_t size_mask = ~ (DEFAULT_PAGE_SIZE - 1); /* pagesize */
int page_index = (virt & size_mask) / DEFAULT_PAGE_SIZE; /* index into page_descriptor array */
struct page_descriptor *page = &pages[page_index]; /* attributes of page to map */
int ipl;
int32_t phys = lookup_phys(virt); /* virtual to physical translation of page */
if (phys == -1)
{
/* no valid mapping found, caller will issue a bus error in return */
return 0;
}
#ifdef DBG_MMU
register int sp asm("sp");
dbg("page_descriptor: 0x%02x, ssp = 0x%08x\r\n", * (uint8_t *) page, sp);
#endif /* DBG_MMU */
/*
* add page to TLB
*/
ipl = set_ipl(7); /* do not disturb */
MCF_MMU_MMUAR = (virt & size_mask);
MCF_MMU_MMUTR = (virt & size_mask) | /* virtual address */
MCF_MMU_MMUTR_ID(asid) | /* address space id (ASID) */
(page->global ? MCF_MMU_MMUTR_SG : 0) | /* shared global */
MCF_MMU_MMUTR_V; /* valid */
MCF_MMU_MMUDR = (phys & size_mask) | /* physical address */
MCF_MMU_MMUDR_SZ(DEFAULT_PAGE_SIZE) | /* page size */
MCF_MMU_MMUDR_CM(page->cache_mode) | /* cache mode */
(page->supervisor_protect ? MCF_MMU_MMUDR_SP : 0) | /* supervisor protect */
(page->read ? MCF_MMU_MMUDR_R : 0) | /* read access enable */
(page->write ? MCF_MMU_MMUDR_W : 0) | /* write access enable */
(page->execute ? MCF_MMU_MMUDR_X : 0) | /* execute access enable */
(page->locked ? MCF_MMU_MMUDR_LK : 0);
MCF_MMU_MMUOR = MCF_MMU_MMUOR_ITLB | /* instruction */
MCF_MMU_MMUOR_ACC | /* access TLB */
MCF_MMU_MMUOR_UAA; /* update allocation address field */
set_ipl(ipl);
dbg("mapped virt=0x%08x to phys=0x%08x\r\n", virt & size_mask, phys & size_mask);
dbg("ITLB: MCF_MMU_MMUOR = %08x\r\n", MCF_MMU_MMUOR);
return 1;
}
int mmu_map_data_page(int32_t virt, uint8_t asid)
{
uint16_t ipl;
const uint32_t size_mask = ~ (DEFAULT_PAGE_SIZE - 1); /* pagesize */
int page_index = (virt & size_mask) / DEFAULT_PAGE_SIZE; /* index into page_descriptor array */
struct page_descriptor *page = &pages[page_index]; /* attributes of page to map */
int32_t phys = lookup_phys(virt); /* virtual to physical translation of page */
if (phys == -1)
{
/* no valid mapping found, caller will issue a bus error in return */
return 0;
}
#ifdef DBG_MMU
register int sp asm("sp");
dbg("page_descriptor: 0x%02x, ssp = 0x%08x\r\n", * (uint8_t *) page, sp);
#endif /* DBG_MMU */
/*
* add page to TLB
*/
ipl = set_ipl(7); /* do not disturb */
MCF_MMU_MMUTR = (virt & size_mask) | /* virtual address */
MCF_MMU_MMUTR_ID(asid) | /* address space id (ASID) */
(page->global ? MCF_MMU_MMUTR_SG : 0) | /* shared global */
MCF_MMU_MMUTR_V; /* valid */
MCF_MMU_MMUDR = (phys & size_mask) | /* physical address */
MCF_MMU_MMUDR_SZ(DEFAULT_PAGE_SIZE) | /* page size */
MCF_MMU_MMUDR_CM(page->cache_mode) | /* cache mode */
(page->supervisor_protect ? MCF_MMU_MMUDR_SP : 0) | /* supervisor protect */
(page->read ? MCF_MMU_MMUDR_R : 0) | /* read access enable */
(page->write ? MCF_MMU_MMUDR_W : 0) | /* write access enable */
(page->execute ? MCF_MMU_MMUDR_X : 0) | /* execute access enable */
(page->locked ? MCF_MMU_MMUDR_LK : 0);
MCF_MMU_MMUOR = MCF_MMU_MMUOR_ACC | /* access TLB, data */
MCF_MMU_MMUOR_UAA; /* update allocation address field */
set_ipl(ipl);
dbg("mapped virt=0x%08x to phys=0x%08x\r\n", virt & size_mask, phys & size_mask);
dbg("DTLB: MCF_MMU_MMUOR = %08x\r\n", MCF_MMU_MMUOR);
return 1;
}
/*
* map a page of memory using virt and phys as addresses with the Coldfire MMU.
*
* Theory of operation: the Coldfire MMU in the Firebee has 64 TLB entries, 32 for data (DTLB), 32 for
* instructions (ITLB). Mappings can either be done locked (normal MMU TLB misses will not consider them
* for replacement) or unlocked (mappings will reallocate using a LRU scheme when the MMU runs out of
* TLB entries). For proper operation, the MMU needs at least two ITLBs and/or four free/allocatable DTLBs
* per instruction as a minimum, more for performance. Thus locked pages (that can't be touched by the
* LRU algorithm) should be used sparsingly.
*/
int mmu_map_page(int32_t virt, int32_t phys, enum mmu_page_size sz, uint8_t page_id, const struct page_descriptor *flags)
{
int size_mask;
int ipl;
switch (sz)
{
case MMU_PAGE_SIZE_1M:
size_mask = ~ (SIZE_1M - 1);
break;
case MMU_PAGE_SIZE_8K:
size_mask = ~ (SIZE_8K - 1);
break;
case MMU_PAGE_SIZE_4K:
size_mask = ~ (SIZE_4K - 1);
break;
case MMU_PAGE_SIZE_1K:
size_mask = ~ (SIZE_1K - 1);
break;
default:
dbg("illegal map size %d\r\n", sz);
return 0;
}
/*
* add page to TLB
*/
ipl = set_ipl(7); /* do not disturb */
MCF_MMU_MMUTR = ((int) virt & size_mask) | /* virtual address */
MCF_MMU_MMUTR_ID(page_id) | /* address space id (ASID) */
(flags->global ? MCF_MMU_MMUTR_SG : 0) | /* shared global */
MCF_MMU_MMUTR_V; /* valid */
MCF_MMU_MMUDR = ((int) phys & size_mask) | /* physical address */
MCF_MMU_MMUDR_SZ(sz) | /* page size */
MCF_MMU_MMUDR_CM(flags->cache_mode) |
(flags->read ? MCF_MMU_MMUDR_R : 0) | /* read access enable */
(flags->write ? MCF_MMU_MMUDR_W : 0) | /* write access enable */
(flags->execute ? MCF_MMU_MMUDR_X : 0) | /* execute access enable */
(flags->locked ? MCF_MMU_MMUDR_LK : 0);
MCF_MMU_MMUOR = MCF_MMU_MMUOR_ACC | /* access TLB, data */
MCF_MMU_MMUOR_UAA; /* update allocation address field */
NOP();
MCF_MMU_MMUOR = MCF_MMU_MMUOR_ITLB | /* instruction */
MCF_MMU_MMUOR_ACC | /* access TLB */
MCF_MMU_MMUOR_UAA; /* update allocation address field */
set_ipl(ipl);
dbg("mapped virt=0x%08x to phys=0x%08x\r\n", virt, phys);
return 1;
}
void mmu_init(void)
{
extern uint8_t _MMUBAR[];
uint32_t MMUBAR = (uint32_t) &_MMUBAR[0];
struct page_descriptor flags;
int i;
/*
* clear all MMU TLB entries first
*/
MCF_MMU_MMUOR = MCF_MMU_MMUOR_CA; /* clears _all_ TLBs (including locked ones) */
NOP();
/*
* prelaminary initialization of page descriptor 0 (root) table
*/
for (i = 0; i < sizeof(pages) / sizeof(struct page_descriptor); i++)
{
uint32_t addr = i * DEFAULT_PAGE_SIZE;
#if defined(MACHINE_FIREBEE)
if (addr >= 0x00f00000UL && addr < 0x00ffffffUL) /* Falcon I/O area on the Firebee */
{
pages[i].cache_mode = CACHE_NOCACHE_PRECISE;
pages[i].execute = 0;
pages[i].read = 1;
pages[i].write = 1;
pages[i].execute = 0;
pages[i].global = 1;
pages[i].supervisor_protect = 1;
}
else if (addr >= 0x0UL && addr < 0x00e00000UL) /* ST-RAM, potential video memory */
{
pages[i].cache_mode = CACHE_WRITETHROUGH;
pages[i].execute = 1;
pages[i].supervisor_protect = 0;
pages[i].read = 1;
pages[i].write = 1;
pages[i].execute = 1;
pages[i].global = 1;
}
else if (addr >= 0x00e00000UL && addr < 0x00f00000UL) /* EmuTOS */
{
pages[i].cache_mode = CACHE_COPYBACK;
pages[i].execute = 1;
pages[i].supervisor_protect = 1;
pages[i].read = 1;
pages[i].write = 0;
pages[i].execute = 1;
pages[i].global = 1;
}
else
{
pages[i].cache_mode = CACHE_COPYBACK;
pages[i].execute = 1;
pages[i].read = 1;
pages[i].write = 1;
pages[i].supervisor_protect = 0;
pages[i].global = 1;
}
pages[i].locked = 0; /* not locked */
pages[0].supervisor_protect = 0; /* protect system vectors */
#elif defined(MACHINE_M5484LITE)
if (addr >= 0x60000000UL && addr < 0x70000000UL) /* Compact Flash on the m5484lite */
{
pages[i].cache_mode = CACHE_NOCACHE_PRECISE;
pages[i].execute = 0;
pages[i].read = 1;
pages[i].write = 1;
pages[i].execute = 0;
pages[i].global = 1;
pages[i].supervisor_protect = 1;
}
else if (addr >= 0x0UL && addr < 0x00e00000UL) /* ST-RAM, potential video memory */
{
pages[i].cache_mode = CACHE_WRITETHROUGH;
pages[i].execute = 1;
pages[i].supervisor_protect = 0;
pages[i].read = 1;
pages[i].write = 1;
pages[i].execute = 1;
pages[i].global = 1;
}
else if (addr >= 0x00e00000UL && addr < 0x00f00000UL) /* EmuTOS */
{
pages[i].cache_mode = CACHE_COPYBACK;
pages[i].execute = 1;
pages[i].supervisor_protect = 1;
pages[i].read = 1;
pages[i].write = 0;
pages[i].execute = 1;
pages[i].global = 1;
}
else
{
pages[i].cache_mode = CACHE_COPYBACK; /* rest of RAM */
pages[i].execute = 1;
pages[i].read = 1;
pages[i].write = 1;
pages[i].supervisor_protect = 0;
pages[i].global = 1;
}
pages[i].locked = 0; /* not locked */
pages[0].supervisor_protect = 0; /* protect system vectors */
#elif defined(MACHINE_M54455)
if (addr >= 0x60000000UL && addr < 0x70000000UL) /* Compact Flash on the m5484lite */
{
pages[i].cache_mode = CACHE_NOCACHE_PRECISE;
pages[i].execute = 0;
pages[i].read = 1;
pages[i].write = 1;
pages[i].execute = 0;
pages[i].global = 1;
pages[i].supervisor_protect = 1;
}
else if (addr >= 0x0UL && addr < 0x00e00000UL) /* ST-RAM, potential video memory */
{
pages[i].cache_mode = CACHE_WRITETHROUGH;
pages[i].execute = 1;
pages[i].supervisor_protect = 0;
pages[i].read = 1;
pages[i].write = 1;
pages[i].execute = 1;
pages[i].global = 1;
}
else if (addr >= 0x00e00000UL && addr < 0x00f00000UL) /* EmuTOS */
{
pages[i].cache_mode = CACHE_COPYBACK;
pages[i].execute = 1;
pages[i].supervisor_protect = 1;
pages[i].read = 1;
pages[i].write = 0;
pages[i].execute = 1;
pages[i].global = 1;
}
else
{
pages[i].cache_mode = CACHE_COPYBACK; /* rest of RAM */
pages[i].execute = 1;
pages[i].read = 1;
pages[i].write = 1;
pages[i].supervisor_protect = 0;
pages[i].global = 1;
}
pages[i].locked = 0; /* not locked */
pages[0].supervisor_protect = 0; /* protect system vectors */
#else
#error Unknown machine!
#endif /* MACHINE_FIREBEE */
}
set_asid(0); /* do not use address extension (ASID provides virtual 48 bit addresses */
/* set data access attributes in ACR0 and ACR1 */
/* map PCI address space */
set_acr0(ACR_W(0) | /* read and write accesses permitted */
ACR_SP(1) | /* supervisor and user mode access permitted */
ACR_CM(ACR_CM_CACHE_INH_PRECISE) | /* cache inhibit, precise */
ACR_AMM(0) | /* control region > 16 MB */
ACR_S(ACR_S_SUPERVISOR_MODE) | /* match addresses in supervisor mode only */
ACR_E(1) | /* enable ACR */
#if defined(MACHINE_FIREBEE)
ACR_ADMSK(0x7f) | /* cover 2GB area from 0x80000000 to 0xffffffff */
ACR_BA(0x80000000)); /* (equals area from 3 to 4 GB */
#elif defined(MACHINE_M5484LITE)
ACR_ADMSK(0x7f) | /* cover 2 GB area from 0x80000000 to 0xffffffff */
ACR_BA(0x80000000));
#elif defined(MACHINE_M54455)
ACR_ADMSK(0x7f) |
ACR_BA(0x80000000)); /* FIXME: not determined yet */
#else
#error unknown machine!
#endif /* MACHINE_FIREBEE */
// set_acr1(0x601fc000);
/* data access attributes for BaS in flash */
set_acr1(ACR_W(0) |
ACR_SP(0) |
ACR_CM(0) |
#if defined(MACHINE_FIREBEE)
ACR_CM(ACR_CM_CACHEABLE_WT) |
#elif defined(MACHINE_M5484LITE)
ACR_CM(ACR_CM_CACHEABLE_WT) |
#elif defined(MACHINE_M54455)
ACR_CM(ACR_CM_CACHEABLE_WT) |
#else
#error unknown machine!
#endif /* MACHINE_FIREBEE */
ACR_AMM(0) |
ACR_S(ACR_S_ALL) |
ACR_E(1) |
ACR_ADMSK(0x1f) |
ACR_BA(0xe0000000));
/* set instruction access attributes in ACR2 and ACR3 */
//set_acr2(0xe007c400);
/* instruction access attribute for BaS in flash */
set_acr2(ACR_W(0) |
ACR_SP(0) |
ACR_CM(0) |
ACR_CM(ACR_CM_CACHEABLE_WT) |
ACR_AMM(1) |
ACR_S(ACR_S_ALL) |
ACR_E(1) |
ACR_ADMSK(0x7) |
ACR_BA(0xe0000000));
/* disable ACR1 - 3, essentially disabling all of the above */
set_acr3(0x0);
set_mmubar(MMUBAR + 1); /* set and enable MMUBAR */
/* create locked TLB entries */
flags.cache_mode = CACHE_COPYBACK;
flags.supervisor_protect = 0;
flags.read = 1;
flags.write = 1;
flags.execute = 1;
flags.locked = true;
/* 0x00000000 - 0x00100000 (first MB of physical memory) locked virt = phys */
mmu_map_page(0x0, 0x0, MMU_PAGE_SIZE_1M, 0, &flags);
#ifdef _NOT_USED_
#if defined(MACHINE_FIREBEE)
/*
* 0x00d00000 - 0x00e00000 (last megabyte of ST RAM = Falcon video memory) locked ID = 6
* mapped to physical address 0x60d0'0000 (FPGA video memory)
* video RAM: read write execute normal write true
*/
flags.cache_mode = CACHE_WRITETHROUGH;
flags.supervisor_protect = 0;
flags.read = 1;
flags.write = 1;
flags.execute = 1;
flags.locked = true;
mmu_map_page(0x00d00000, 0x60d00000, MMU_PAGE_SIZE_1M, SCA_PAGE_ID, &flags);
#endif /* MACHINE_FIREBEE */
#endif
/*
* Make the TOS (in SDRAM) read-only
* This maps virtual 0x00e0'0000 - 0x00ef'ffff to the same virtual address
*/
flags.cache_mode = CACHE_COPYBACK;
flags.supervisor_protect = 0;
flags.read = 1;
flags.write = 0;
flags.execute = 1;
flags.locked = 1;
mmu_map_page(0xe00000, 0xe00000, MMU_PAGE_SIZE_1M, 0, &flags);
#if defined(MACHINE_FIREBEE)
/*
* Map FireBee I/O area (0xfff0'0000 - 0xffff'ffff physical) to the Falcon-compatible I/O
* area (0x00f0'0000 - 0x00ff'ffff virtual) for the FireBee
*/
flags.cache_mode = CACHE_NOCACHE_PRECISE;
flags.supervisor_protect = 1;
flags.read = 1;
flags.write = 1;
flags.execute = 0;
flags.locked = 1;
mmu_map_page(0x00f00000, 0xfff00000, MMU_PAGE_SIZE_1M, 0, &flags);
#endif /* MACHINE_FIREBEE */
/*
* Map (locked) the second last MB of physical SDRAM (this is where BaS .data and .bss reside) to the same
* virtual address. This is also used (completely) when BaS is in RAM
*/
flags.cache_mode = CACHE_COPYBACK;
flags.supervisor_protect = 1;
flags.read = 1;
flags.write = 1;
flags.execute = 1;
flags.locked = 1;
mmu_map_page(SDRAM_START + SDRAM_SIZE - 0x00200000, SDRAM_START + SDRAM_SIZE - 0x00200000, MMU_PAGE_SIZE_1M, 0, &flags);
/*
* Map (locked) the very last MB of physical SDRAM (this is where the driver buffers reside) to the same
* virtual address. Used uncached for drivers.
*/
flags.cache_mode = CACHE_NOCACHE_PRECISE;
flags.supervisor_protect = 1;
flags.read = 1;
flags.write = 1;
flags.execute = 0;
flags.locked = 1;
mmu_map_page(SDRAM_START + SDRAM_SIZE - 0x00100000, SDRAM_START + SDRAM_SIZE - 0x00100000, MMU_PAGE_SIZE_1M, 0, &flags);
}
uint32_t mmutr_miss(uint32_t mmu_sr, uint32_t fault_address, uint32_t pc,
uint32_t format_status)
{
uint32_t fault = format_status & 0xc030000;
dbg("MMU TLB MISS accessing 0x%08x\r\nFS = 0x%08x\r\nPC = 0x%08x\r\n", fault_address, format_status, pc);
// flush_and_invalidate_caches();
switch (fault)
{
/* if we have a real TLB miss, map the offending page */
case 0x04010000: /* TLB miss on opword of instruction fetch */
case 0x04020000: /* TLB miss on extension word of instruction fetch */
dbg("MMU ITLB MISS accessing 0x%08x\r\n"
"FS = 0x%08x\r\n"
"MMUSR = 0x%08x\r\n"
"PC = 0x%08x\r\n",
fault_address, format_status, mmu_sr, pc);
dbg("fault = 0x%08x\r\n", fault);
if (!mmu_map_instruction_page(pc, 0))
{
dbg("bus error\r\n");
return 1; /* bus error */
}
/* due to prefetch, it makes sense to map the next adjacent page also for ITLBs */
if (pc + DEFAULT_PAGE_SIZE < TARGET_ADDRESS)
{
/*
* only do this if the next page is still valid RAM
*/
if (!mmu_map_instruction_page(pc + DEFAULT_PAGE_SIZE, 0))
{
dbg("bus error\r\n");
return 1; /* bus error */
}
}
break;
case 0x08020000: /* TLB miss on data write */
case 0x0c020000: /* TLB miss on data read or read-modify-write */
dbg("MMU DTLB MISS accessing 0x%08x\r\n"
"FS = 0x%08x\r\n"
"MMUSR = 0x%08x\r\n"
"PC = 0x%08x\r\n",
fault_address, format_status, mmu_sr, pc);
dbg("fault = 0x%08x\r\n", fault);
if (!mmu_map_data_page(fault_address, 0))
{
dbg("bus error\r\n");
return 1; /* bus error */
}
break;
/* else issue an bus error */
default:
dbg("bus error\r\n");
return 1; /* signal bus error to caller */
}
#ifdef DBG_MMU
xprintf("\r\n");
#endif /* DBG_MMU */
return 0; /* signal TLB miss handled to caller */
}
/* TODO: implement */
/*
* API-exposed, externally callable MMU functions
*/
/*
* lock data page(s) with address space id asid from address virt to virt + size.
*
* ASID probably needs an explanation - this is the "address space id" managed by
* the MMU.
* If its value range would be large enough, this could directly map to a PID
* in MiNT. Unfortunately, the Coldfire MMU only allows an 8 bit value for ASID
* (with 0 already occupied for the super user/root process and the Firebee video
* subsystem occupying another one), so we are left with 253 distinct values.
* MMU software needs to implement some kind of mapping and LRU scheme which will
* lead to a throwaway of all mappings for processes not seen for a while (and thus
* to undeterministic response/task switching times when such processes are activated
* again).
*
* FIXME: There is no check for "too many locked pages", currently.
*
* return: 0 if failed (page not in translation table), 1 otherwise
*/
int32_t mmu_map_data_page_locked(uint32_t virt, uint32_t size, int asid)
{
const uint32_t size_mask = ~ (DEFAULT_PAGE_SIZE - 1); /* pagesize */
int page_index = (virt & size_mask) / DEFAULT_PAGE_SIZE; /* index into page_descriptor array */
struct page_descriptor *page = &pages[page_index]; /* attributes of page to map */
int i = 0;
while (page_index * DEFAULT_PAGE_SIZE < virt + size)
{
if (page->locked)
{
dbg("page at %p is already locked. Nothing to do\r\n", virt);
}
else
{
page->locked = 1;
mmu_map_data_page(virt, 0);
i++;
}
virt += DEFAULT_PAGE_SIZE;
}
dbg("%d pages locked\r\n", i);
return 1; /* success */
}
/*
* the opposite: unlock data page(s) with address space id asid from address virt to virt + size_t
*
* return: 0 if failed (page not found), 1 otherwise
*/
int32_t mmu_unlock_data_page(uint32_t address, uint32_t size, int asid)
{
int curr_asid;
const uint32_t size_mask = ~ (DEFAULT_PAGE_SIZE - 1);
int page_index = (address & size_mask) / DEFAULT_PAGE_SIZE; /* index into page descriptor array */
struct page_descriptor *page = &pages[page_index];
curr_asid = set_asid(asid); /* set asid to the one to search for */
/* TODO: check for pages[] array bounds */
while (page_index * DEFAULT_PAGE_SIZE < address + size)
{
MCF_MMU_MMUAR = address + page->supervisor_protect;
MCF_MMU_MMUOR = MCF_MMU_MMUOR_STLB | /* search TLB */
MCF_MMU_MMUOR_ADR |
MCF_MMU_MMUOR_RW;
if (MCF_MMU_MMUSR & MCF_MMU_MMUSR_HIT) /* found */
{
#ifdef DBG_MMU
uint32_t tlb_aa = MCF_MMU_MMUOR >> 16; /* MMU internal allocation address for TLB */
#endif /* DBG_MMU */
MCF_MMU_MMUDR &= ~MCF_MMU_MMUDR_LK; /* clear lock bit */
MCF_MMU_MMUOR = MCF_MMU_MMUOR_UAA |
MCF_MMU_MMUOR_ACC; /* update TLB */
dbg("DTLB %d unlocked\r\n", tlb_aa);
}
else
{
dbg("%p doesn't seem to be locked??\r\n");
}
page_index++;
}
set_asid(curr_asid);
return 1; /* success */
}
int32_t mmu_report_locked_pages(uint32_t *num_itlb, uint32_t *num_dtlb)
{
int i;
int li = 0;
int ld = 0;
/* Coldfire V4e allocation addresses run from 0 to 63 */
for (i = 0; i < 31; i++) /* 0-31 = ITLB AA */
{
MCF_MMU_MMUAR = i;
MCF_MMU_MMUOR = MCF_MMU_MMUOR_STLB |
MCF_MMU_MMUOR_ITLB |
MCF_MMU_MMUOR_RW; /* search ITLB */
if (MCF_MMU_MMUTR & MCF_MMU_MMUTR_V)
{
/* entry is valid */
if (MCF_MMU_MMUDR & MCF_MMU_MMUDR_LK)
{
li++;
}
}
}
for (i = 32; i < 64; i++) /* 32-63 = DTLB AA */
{
MCF_MMU_MMUAR = i;
MCF_MMU_MMUOR = MCF_MMU_MMUOR_STLB |
MCF_MMU_MMUOR_RW; /* search ITLB */
if (MCF_MMU_MMUTR & MCF_MMU_MMUTR_V)
{
/* entry is valid */
if (MCF_MMU_MMUDR & MCF_MMU_MMUDR_LK)
{
ld++;
}
}
}
*num_itlb = li;
*num_dtlb = ld;
return 1; /* success */
}
uint32_t mmu_report_pagesize(void)
{
return DEFAULT_PAGE_SIZE;
}
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