Firebee/FireBee_SVN
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

experimental branh to use 8k memory pages in MMU TLBs - might ease

Browse Source 
implementing memory protection for Coldfire in MiNT
This commit is contained in:
Markus Fröschle
2014-09-25 13:50:07 +00:00
parent db847ec588
commit 8d67a33c75
3 changed files with 94 additions and 150 deletions
Download Patch File Download Diff File Expand all files Collapse all files

159
Bas_gcc_mmu/sys/mmu.c
View File

@@ -68,6 +68,20 @@
#else
#define dbg(format, arg...) do {;} while (0)
#endif /* DEBUG_MMU */
#define err(format, arg...) do { xprintf("ERROR (%s()): " format, __FUNCTION__, ##arg);} while(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;
};
static struct page_descriptor pages[65536]; /* 512 Mb RAM */
/*
* set ASID register
@@ -189,6 +203,39 @@ inline uint32_t set_mmubar(uint32_t value)
return ret;
}
/*
* translation table for virtual addresses. Holds the virtual_offset (which must be added to a physical
* address to get its virtual counterpart) for memory ranges.
* Currently, this contains only the STRAM addresses which are mapped to Firebee video memory
*/
struct phys_to_virt
{
uint32_t start_address;
uint32_t length;
uint32_t virtual_offset;
};
static struct phys_to_virt translation[] =
{
{ 0x00000000, 0x01000000, 0x60000000 }, /* map first 16 MByte to first 16 Mb of video ram */
{ 0x01000000, 0x10000000, 0x00000000 }, /* map rest of ram virt = phys */
};
static int num_translations = sizeof(translation) / sizeof(struct phys_to_virt);
static inline uint32_t lookup_virtual(uint32_t phys)
{
int i;
for (i = 0; i < num_translations; i++)
{
if (phys >= translation[i].start_address && phys < translation[i].start_address + translation[i].length)
{
return phys + translation[i].virtual_offset;
}
}
err("physical address 0x%lx not found in translation table!\r\n", phys);
}
/*
* map a page of memory using virt and phys as addresses with the Coldfire MMU.
*
@@ -201,49 +248,29 @@ inline uint32_t set_mmubar(uint32_t value)
*
*
*/
int mmu_map_page(uint32_t virt, uint32_t phys, enum mmu_page_size sz, const struct mmu_map_flags *flags)
int mmu_map_page(uint32_t adr)
{
int size_mask;
switch (sz)
{
case MMU_PAGE_SIZE_1M:
size_mask = 0xfff00000;
break;
case MMU_PAGE_SIZE_8K:
size_mask = 0xffffe000;
break;
case MMU_PAGE_SIZE_4K:
size_mask = 0xfffff000;
break;
case MMU_PAGE_SIZE_1K:
size_mask = 0xfffff800;
break;
default:
dbg("illegal map size %d\r\n", sz);
return 0;
}
const int size_mask = 0xffffe000; /* 8k pagesize */
int page_index = (adr & size_mask) / 4096; /* index into page_descriptor array */
struct page_descriptor *page = &pages[page_index]; /* attributes of page to map */
uint32_t virt = lookup_virtual(adr); /* phys2virt translation of page */
/*
* add page to TLB
*/
MCF_MMU_MMUTR = ((int) virt & size_mask) | /* virtual address */
MCF_MMU_MMUTR_ID(flags->page_id) | /* address space id (ASID) */
MCF_MMU_MMUTR = (virt & size_mask) | /* virtual address */
MCF_MMU_MMUTR_ID(0x00) | /* address space id (ASID) */
MCF_MMU_MMUTR_SG | /* shared global */
MCF_MMU_MMUTR_V; /* valid */
NOP();
MCF_MMU_MMUDR = ((int) phys & size_mask) | /* physical address */
MCF_MMU_MMUDR_SZ(sz) | /* page size */
MCF_MMU_MMUDR_CM(flags->cache_mode) |
(flags->access & ACCESS_READ ? MCF_MMU_MMUDR_R : 0) | /* read access enable */
(flags->access & ACCESS_WRITE ? MCF_MMU_MMUDR_W : 0) | /* write access enable */
(flags->access & ACCESS_EXECUTE ? MCF_MMU_MMUDR_X : 0) | /* execute access enable */
(flags->locked ? MCF_MMU_MMUDR_LK : 0);
MCF_MMU_MMUDR = (adr & size_mask) | /* physical address */
MCF_MMU_MMUDR_SZ(MMU_PAGE_SIZE_8K) | /* page size */
MCF_MMU_MMUDR_CM(page->cache_mode) |
(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);
NOP();
MCF_MMU_MMUOR = MCF_MMU_MMUOR_ACC | /* access TLB, data */
@@ -260,8 +287,6 @@ int mmu_map_page(uint32_t virt, uint32_t phys, enum mmu_page_size sz, const stru
void mmu_init(void)
{
struct mmu_map_flags flags;
extern uint8_t _MMUBAR[];
uint32_t MMUBAR = (uint32_t) &_MMUBAR[0];
extern uint8_t _TOS[];
@@ -331,14 +356,14 @@ void mmu_init(void)
/* create locked TLB entries */
flags.cache_mode = CACHE_COPYBACK;
flags.protection = SV_USER;
flags.page_id = 0;
flags.access = ACCESS_READ | ACCESS_WRITE | ACCESS_EXECUTE;
flags.locked = true;
//flags.cache_mode = CACHE_COPYBACK;
//flags.protection = SV_USER;
//flags.page_id = 0;
//flags.access = ACCESS_READ | ACCESS_WRITE | ACCESS_EXECUTE;
//flags.locked = true;
/* 0x0000_0000 - 0x000F_FFFF (first MB of physical memory) locked virt = phys */
mmu_map_page(0x0, 0x0, MMU_PAGE_SIZE_1M, &flags);
//mmu_map_page(0x0, 0x0, MMU_PAGE_SIZE_1M, &flags);
#if defined(MACHINE_FIREBEE)
/*
@@ -346,54 +371,55 @@ void mmu_init(void)
* mapped to physical address 0x60d0'0000 (FPGA video memory)
* video RAM: read write execute normal write true
*/
flags.cache_mode = CACHE_WRITETHROUGH;
flags.protection = SV_USER;
flags.page_id = SCA_PAGE_ID;
flags.access = ACCESS_READ | ACCESS_WRITE | ACCESS_EXECUTE;
flags.locked = true;
mmu_map_page(0x00d00000, 0x60d00000, MMU_PAGE_SIZE_1M, &flags);
//flags.cache_mode = CACHE_WRITETHROUGH;
//flags.protection = SV_USER;
//flags.page_id = SCA_PAGE_ID;
//flags.access = ACCESS_READ | ACCESS_WRITE | ACCESS_EXECUTE;
//flags.locked = true;
//mmu_map_page(0x00d00000, 0x60d00000, MMU_PAGE_SIZE_1M, &flags);
video_tlb = 0x2000; /* set page as video page */
video_sbt = 0x0; /* clear time */
//video_tlb = 0x2000; /* set page as video page */
//video_sbt = 0x0; /* clear time */
#endif /* MACHINE_FIREBEE */
/*
* 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.page_id = 0;
flags.access = ACCESS_READ | ACCESS_EXECUTE;
mmu_map_page(TOS, TOS, MMU_PAGE_SIZE_1M, &flags);
//flags.cache_mode = CACHE_COPYBACK;
//flags.page_id = 0;
//flags.access = ACCESS_READ | ACCESS_EXECUTE;
//mmu_map_page(TOS, TOS, MMU_PAGE_SIZE_1M, &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.access = ACCESS_WRITE | ACCESS_READ;
mmu_map_page(0x00f00000, 0xfff00000, MMU_PAGE_SIZE_1M, &flags);
//flags.cache_mode = CACHE_NOCACHE_PRECISE;
//flags.access = ACCESS_WRITE | ACCESS_READ;
//mmu_map_page(0x00f00000, 0xfff00000, MMU_PAGE_SIZE_1M, &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.access = ACCESS_READ | ACCESS_WRITE | ACCESS_EXECUTE;
mmu_map_page(SDRAM_START + SDRAM_SIZE - 0X00200000, SDRAM_START + SDRAM_SIZE - 0X00200000, MMU_PAGE_SIZE_1M, &flags);
//flags.cache_mode = CACHE_COPYBACK;
//flags.access = ACCESS_READ | ACCESS_WRITE | ACCESS_EXECUTE;
//mmu_map_page(SDRAM_START + SDRAM_SIZE - 0X00200000, SDRAM_START + SDRAM_SIZE - 0X00200000, MMU_PAGE_SIZE_1M, &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.access = ACCESS_READ | ACCESS_WRITE;
flags.protection = SV_PROTECT;
mmu_map_page(SDRAM_START + SDRAM_SIZE - 0x00100000, SDRAM_START + SDRAM_SIZE - 0x00100000, MMU_PAGE_SIZE_1M, &flags);
//flags.cache_mode = CACHE_NOCACHE_PRECISE;
//flags.access = ACCESS_READ | ACCESS_WRITE;
//flags.protection = SV_PROTECT;
//mmu_map_page(SDRAM_START + SDRAM_SIZE - 0x00100000, SDRAM_START + SDRAM_SIZE - 0x00100000, MMU_PAGE_SIZE_1M, &flags);
}
/*
static struct mmu_map_flags flags =
{
.cache_mode = CACHE_COPYBACK,
@@ -402,11 +428,12 @@ static struct mmu_map_flags flags =
.access = ACCESS_READ | ACCESS_WRITE | ACCESS_EXECUTE,
.locked = false
};
*/
void mmutr_miss(uint32_t address, uint32_t pc, uint32_t format_status)
{
dbg("MMU TLB MISS accessing 0x%08x\r\nFS = 0x%08x\r\nPC = 0x%08x\r\n", address, format_status, pc);
// flush_and_invalidate_caches();
flush_cache_range((void *) address, 8192);
switch (address)
{
@@ -424,7 +451,7 @@ void mmutr_miss(uint32_t address, uint32_t pc, uint32_t format_status)
default:
/* add missed page to TLB */
mmu_map_page(address, address, MMU_PAGE_SIZE_1M, &flags);
mmu_map_page(address);
dbg("DTLB: MCF_MMU_MMUOR = %08x\r\n", MCF_MMU_MMUOR);
dbg("ITLB: MCF_MMU_MMUOR = %08x\r\n\r\n", MCF_MMU_MMUOR);
}