rt-thread/libcpu/mips/gs264/mmu.c

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2020-09-04 09:31:42 +08:00
/*
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* Copyright (c) 2006-2021, RT-Thread Development Team
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*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2012-01-10 bernard porting to AM1808
* 2020-07-26 lizhirui porting to ls2k
*/
#include <rtthread.h>
#include <rthw.h>
#include <board.h>
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#include <stddef.h>
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#include "cache.h"
#include "mips_mmu.h"
#include "mmu.h"
void *current_mmu_table = RT_NULL;
void *mmu_table_get()
{
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return current_mmu_table;
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}
void switch_mmu(void *mmu_table)
{
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current_mmu_table = mmu_table;
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mmu_clear_tlb();
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mmu_clear_itlb();
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}
/* dump 2nd level page table */
void rt_hw_cpu_dump_page_table_2nd(rt_uint32_t *ptb)
{
int i;
int fcnt = 0;
for (i = 0; i < 256; i++)
{
rt_uint32_t pte2 = ptb[i];
if ((pte2 & 0x3) == 0)
{
if (fcnt == 0)
rt_kprintf(" ");
rt_kprintf("%04x: ", i);
fcnt++;
if (fcnt == 16)
{
rt_kprintf("fault\n");
fcnt = 0;
}
continue;
}
if (fcnt != 0)
{
rt_kprintf("fault\n");
fcnt = 0;
}
rt_kprintf(" %04x: %x: ", i, pte2);
if ((pte2 & 0x3) == 0x1)
{
rt_kprintf("L,ap:%x,xn:%d,texcb:%02x\n",
((pte2 >> 7) | (pte2 >> 4))& 0xf,
(pte2 >> 15) & 0x1,
((pte2 >> 10) | (pte2 >> 2)) & 0x1f);
}
else
{
rt_kprintf("S,ap:%x,xn:%d,texcb:%02x\n",
((pte2 >> 7) | (pte2 >> 4))& 0xf, pte2 & 0x1,
((pte2 >> 4) | (pte2 >> 2)) & 0x1f);
}
}
}
void rt_hw_cpu_dump_page_table(rt_uint32_t *ptb)
{
int i;
int fcnt = 0;
rt_kprintf("page table@%p\n", ptb);
for (i = 0; i < 1024*4; i++)
{
rt_uint32_t pte1 = ptb[i];
if ((pte1 & 0x3) == 0)
{
rt_kprintf("%03x: ", i);
fcnt++;
if (fcnt == 16)
{
rt_kprintf("fault\n");
fcnt = 0;
}
continue;
}
if (fcnt != 0)
{
rt_kprintf("fault\n");
fcnt = 0;
}
rt_kprintf("%03x: %08x: ", i, pte1);
if ((pte1 & 0x3) == 0x3)
{
rt_kprintf("LPAE\n");
}
else if ((pte1 & 0x3) == 0x1)
{
rt_kprintf("pte,ns:%d,domain:%d\n",
(pte1 >> 3) & 0x1, (pte1 >> 5) & 0xf);
/*
*rt_hw_cpu_dump_page_table_2nd((void*)((pte1 & 0xfffffc000)
* - 0x80000000 + 0xC0000000));
*/
}
else if (pte1 & (1 << 18))
{
rt_kprintf("super section,ns:%d,ap:%x,xn:%d,texcb:%02x\n",
(pte1 >> 19) & 0x1,
((pte1 >> 13) | (pte1 >> 10))& 0xf,
(pte1 >> 4) & 0x1,
((pte1 >> 10) | (pte1 >> 2)) & 0x1f);
}
else
{
rt_kprintf("section,ns:%d,ap:%x,"
"xn:%d,texcb:%02x,domain:%d\n",
(pte1 >> 19) & 0x1,
((pte1 >> 13) | (pte1 >> 10))& 0xf,
(pte1 >> 4) & 0x1,
(((pte1 & (0x7 << 12)) >> 10) |
((pte1 & 0x0c) >> 2)) & 0x1f,
(pte1 >> 5) & 0xf);
}
}
}
/* level1 page table, each entry for 1MB memory. */
volatile unsigned long MMUTable[4*1024] __attribute__((aligned(16*1024)));
void rt_hw_mmu_setmtt(rt_uint32_t vaddrStart,
rt_uint32_t vaddrEnd,
rt_uint32_t paddrStart,
rt_uint32_t attr)
{
volatile rt_uint32_t *pTT;
volatile int i, nSec;
pTT = (rt_uint32_t *)MMUTable + (vaddrStart >> 20);
nSec = (vaddrEnd >> 20) - (vaddrStart >> 20);
for(i = 0; i <= nSec; i++)
{
*pTT = attr | (((paddrStart >> 20) + i) << 20);
pTT++;
}
}
unsigned long rt_hw_set_domain_register(unsigned long domain_val)
{
unsigned long old_domain;
//asm volatile ("mrc p15, 0, %0, c3, c0\n" : "=r" (old_domain));
//asm volatile ("mcr p15, 0, %0, c3, c0\n" : :"r" (domain_val) : "memory");
return old_domain;
}
void rt_hw_cpu_dcache_clean(void *addr, int size);
void rt_hw_init_mmu_table(struct mem_desc *mdesc, rt_uint32_t size)
{
/* set page table */
for(; size > 0; size--)
{
rt_hw_mmu_setmtt(mdesc->vaddr_start, mdesc->vaddr_end,
mdesc->paddr_start, mdesc->attr);
mdesc++;
}
rt_hw_cpu_dcache_clean((void*)MMUTable, sizeof MMUTable);
}
void rt_hw_mmu_init(void)
{
rt_cpu_dcache_clean_flush();
rt_cpu_icache_flush();
rt_hw_cpu_dcache_disable();
rt_hw_cpu_icache_disable();
rt_cpu_mmu_disable();
/*rt_hw_cpu_dump_page_table(MMUTable);*/
rt_hw_set_domain_register(0x55555555);
rt_cpu_tlb_set(MMUTable);
rt_cpu_mmu_enable();
rt_hw_cpu_icache_enable();
rt_hw_cpu_dcache_enable();
}
/*
mem map
*/
void rt_hw_cpu_dcache_clean(void *addr, int size);
int rt_hw_mmu_map_init(rt_mmu_info *mmu_info, void* v_address, size_t size, size_t *vtable, size_t pv_off)
{
size_t l1_off, va_s, va_e;
rt_base_t level;
if (!mmu_info || !vtable)
{
return -1;
}
va_s = (size_t)v_address;
va_e = (size_t)v_address + size - 1;
if ( va_e < va_s)
{
return -1;
}
va_s >>= ARCH_SECTION_SHIFT;
va_e >>= ARCH_SECTION_SHIFT;
if (va_s == 0)
{
return -1;
}
level = rt_hw_interrupt_disable();
for (l1_off = va_s; l1_off <= va_e; l1_off++)
{
size_t v = vtable[l1_off];
if (v & ARCH_MMU_USED_MASK)
{
rt_kprintf("Error:vtable[%d] = 0x%p(is not zero),va_s = 0x%p,va_e = 0x%p!\n",l1_off,v,va_s,va_e);
rt_hw_interrupt_enable(level);
return -1;
}
}
mmu_info->vtable = vtable;
mmu_info->vstart = va_s;
mmu_info->vend = va_e;
mmu_info->pv_off = pv_off;
rt_hw_interrupt_enable(level);
return 0;
}
static size_t find_vaddr(rt_mmu_info *mmu_info, int pages)
{
size_t l1_off, l2_off;
size_t *mmu_l1, *mmu_l2;
size_t find_off = 0;
size_t find_va = 0;
int n = 0;
if (!pages)
{
return 0;
}
if (!mmu_info)
{
return 0;
}
for (l1_off = mmu_info->vstart; l1_off <= mmu_info->vend; l1_off++)
{
mmu_l1 = (size_t*)mmu_info->vtable + l1_off;
if (*mmu_l1 & ARCH_MMU_USED_MASK)
{
mmu_l2 = (size_t *)((*mmu_l1 & ~ARCH_PAGE_TBL_MASK) - mmu_info->pv_off);
for (l2_off = 0; l2_off < (ARCH_SECTION_SIZE/ARCH_PAGE_SIZE); l2_off++)
{
if (*(mmu_l2 + l2_off) & ARCH_MMU_USED_MASK)
{
/* in use */
n = 0;
}
else
{
if (!n)
{
find_va = l1_off;
find_off = l2_off;
}
n++;
if (n >= pages)
{
return (find_va << ARCH_SECTION_SHIFT) + (find_off << ARCH_PAGE_SHIFT);
}
}
}
}
else
{
if (!n)
{
find_va = l1_off;
find_off = 0;
}
n += (ARCH_SECTION_SIZE/ARCH_PAGE_SIZE);
if (n >= pages)
{
return (find_va << ARCH_SECTION_SHIFT) + (find_off << ARCH_PAGE_SHIFT);
}
}
}
return 0;
}
#ifdef RT_USING_USERSPACE
static int check_vaddr(rt_mmu_info *mmu_info, void *va, int pages)
{
size_t loop_va = (size_t)va & ~ARCH_PAGE_MASK;
size_t l1_off, l2_off;
size_t *mmu_l1, *mmu_l2;
if (!pages)
{
return -1;
}
if (!mmu_info)
{
return -1;
}
while (pages--)
{
l1_off = (loop_va >> ARCH_SECTION_SHIFT);
l2_off = ((loop_va & ARCH_SECTION_MASK) >> ARCH_PAGE_SHIFT);
mmu_l1 = (size_t*)mmu_info->vtable + l1_off;
if (*mmu_l1 & ARCH_MMU_USED_MASK)
{
mmu_l2 = (size_t *)((*mmu_l1 & ~ARCH_PAGE_TBL_MASK) - mmu_info->pv_off);
if (*(mmu_l2 + l2_off) & ARCH_MMU_USED_MASK)
{
return -1;
}
}
loop_va += ARCH_PAGE_SIZE;
}
return 0;
}
#endif
static void __rt_hw_mmu_unmap(rt_mmu_info *mmu_info, void* v_addr, size_t npages)
{
size_t loop_va = (size_t)v_addr & ~ARCH_PAGE_MASK;
size_t l1_off, l2_off;
size_t *mmu_l1, *mmu_l2;
size_t *ref_cnt;
if (!mmu_info)
{
return;
}
while (npages--)
{
l1_off = (loop_va >> ARCH_SECTION_SHIFT);
if (l1_off < mmu_info->vstart || l1_off > mmu_info->vend)
{
return;
}
l2_off = ((loop_va & ARCH_SECTION_MASK) >> ARCH_PAGE_SHIFT);
mmu_l1 = (size_t*)mmu_info->vtable + l1_off;
if (*mmu_l1 & ARCH_MMU_USED_MASK)
{
mmu_l2 = (size_t *)((*mmu_l1 & ~ARCH_PAGE_TBL_MASK) - mmu_info->pv_off);
}
else
{
return;
}
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if (*(mmu_l2 + l2_off) & ARCH_MMU_USED_MASK)
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{
*(mmu_l2 + l2_off) = 0;
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l2 + l2_off, 4);
ref_cnt = mmu_l2 + (ARCH_SECTION_SIZE/ARCH_PAGE_SIZE);
(*ref_cnt)--;
if (!*ref_cnt)
{
#ifdef RT_USING_USERSPACE
rt_pages_free(mmu_l2, 0);
#else
rt_free_align(mmu_l2);
#endif
*mmu_l1 = 0;
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l1, 4);
}
}
loop_va += ARCH_PAGE_SIZE;
}
}
static int __rt_hw_mmu_map(rt_mmu_info *mmu_info, void* v_addr, void* p_addr, size_t npages, size_t attr)
{
size_t loop_va = (size_t)v_addr & ~ARCH_PAGE_MASK;
size_t loop_pa = (size_t)p_addr & ~ARCH_PAGE_MASK;
size_t l1_off, l2_off;
size_t *mmu_l1, *mmu_l2;
size_t *ref_cnt;
if (!mmu_info)
{
return -1;
}
while (npages--)
{
l1_off = (loop_va >> ARCH_SECTION_SHIFT);
l2_off = ((loop_va & ARCH_SECTION_MASK) >> ARCH_PAGE_SHIFT);
mmu_l1 = (size_t*)mmu_info->vtable + l1_off;
if (*mmu_l1 & ARCH_MMU_USED_MASK)
{
mmu_l2 = (size_t *)((*mmu_l1 & ~ARCH_PAGE_TBL_MASK) - mmu_info->pv_off);
}
else
{
#ifdef RT_USING_USERSPACE
mmu_l2 = (size_t*)rt_pages_alloc(0);
#else
mmu_l2 = (size_t*)rt_malloc_align(ARCH_PAGE_TBL_SIZE * 2, ARCH_PAGE_TBL_SIZE);
#endif
if (mmu_l2)
{
rt_memset(mmu_l2, 0, ARCH_PAGE_TBL_SIZE * 2);
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l2, ARCH_PAGE_TBL_SIZE);
*mmu_l1 = (((size_t)mmu_l2 + mmu_info->pv_off) | 0x1);
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l1, 4);
}
else
{
/* error, unmap and quit */
__rt_hw_mmu_unmap(mmu_info, v_addr, npages);
return -1;
}
}
ref_cnt = mmu_l2 + (ARCH_SECTION_SIZE/ARCH_PAGE_SIZE);
(*ref_cnt)++;
*(mmu_l2 + l2_off) = (loop_pa | attr);
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l2 + l2_off, 4);
loop_va += ARCH_PAGE_SIZE;
loop_pa += ARCH_PAGE_SIZE;
}
return 0;
}
static void rt_hw_cpu_tlb_invalidate(void)
{
mmu_clear_tlb();
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mmu_clear_itlb();
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}
#ifdef RT_USING_USERSPACE
void *_rt_hw_mmu_map(rt_mmu_info *mmu_info, void *v_addr, void* p_addr, size_t size, size_t attr)
{
size_t pa_s, pa_e;
size_t vaddr;
int pages;
int ret;
if (!size)
{
return 0;
}
pa_s = (size_t)p_addr;
pa_e = (size_t)p_addr + size - 1;
pa_s >>= ARCH_PAGE_SHIFT;
pa_e >>= ARCH_PAGE_SHIFT;
pages = pa_e - pa_s + 1;
if (v_addr)
{
vaddr = (size_t)v_addr;
pa_s = (size_t)p_addr;
if ((vaddr & ARCH_PAGE_MASK) != (pa_s & ARCH_PAGE_MASK))
{
return 0;
}
vaddr &= ~ARCH_PAGE_MASK;
if (check_vaddr(mmu_info, (void*)vaddr, pages) != 0)
{
return 0;
}
}
else
{
vaddr = find_vaddr(mmu_info, pages);
}
if (vaddr) {
ret = __rt_hw_mmu_map(mmu_info, (void*)vaddr, p_addr, pages, attr);
if (ret == 0)
{
rt_hw_cpu_tlb_invalidate();
return (void*)(vaddr + ((size_t)p_addr & ARCH_PAGE_MASK));
}
}
return 0;
}
#else
void *_rt_hw_mmu_map(rt_mmu_info *mmu_info, void* p_addr, size_t size, size_t attr)
{
size_t pa_s, pa_e;
size_t vaddr;
int pages;
int ret;
pa_s = (size_t)p_addr;
pa_e = (size_t)p_addr + size - 1;
pa_s >>= ARCH_PAGE_SHIFT;
pa_e >>= ARCH_PAGE_SHIFT;
pages = pa_e - pa_s + 1;
vaddr = find_vaddr(mmu_info, pages);
if (vaddr) {
ret = __rt_hw_mmu_map(mmu_info, (void*)vaddr, p_addr, pages, attr);
if (ret == 0)
{
rt_hw_cpu_tlb_invalidate();
return (void*)(vaddr + ((size_t)p_addr & ARCH_PAGE_MASK));
}
}
return 0;
}
#endif
#ifdef RT_USING_USERSPACE
static int __rt_hw_mmu_map_auto(rt_mmu_info *mmu_info, void* v_addr, size_t npages, size_t attr)
{
size_t loop_va = (size_t)v_addr & ~ARCH_PAGE_MASK;
size_t loop_pa;
size_t l1_off, l2_off;
size_t *mmu_l1, *mmu_l2;
size_t *ref_cnt;
if (!mmu_info)
{
return -1;
}
while (npages--)
{
loop_pa = (size_t)rt_pages_alloc(0) + mmu_info->pv_off;
if (!loop_pa)
goto err;
//rt_kprintf("vaddr = %08x is mapped to paddr = %08x\n",v_addr,loop_pa);
l1_off = (loop_va >> ARCH_SECTION_SHIFT);
l2_off = ((loop_va & ARCH_SECTION_MASK) >> ARCH_PAGE_SHIFT);
mmu_l1 = (size_t*)mmu_info->vtable + l1_off;
if (*mmu_l1 & ARCH_MMU_USED_MASK)
{
mmu_l2 = (size_t *)((*mmu_l1 & ~ARCH_PAGE_TBL_MASK) - mmu_info->pv_off);
}
else
{
//mmu_l2 = (size_t*)rt_malloc_align(ARCH_PAGE_TBL_SIZE * 2, ARCH_PAGE_TBL_SIZE);
mmu_l2 = (size_t*)rt_pages_alloc(0);
if (mmu_l2)
{
rt_memset(mmu_l2, 0, ARCH_PAGE_TBL_SIZE * 2);
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l2, ARCH_PAGE_TBL_SIZE);
*mmu_l1 = (((size_t)mmu_l2 + mmu_info->pv_off) | 0x1);
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l1, 4);
}
else
goto err;
}
ref_cnt = mmu_l2 + (ARCH_SECTION_SIZE/ARCH_PAGE_SIZE);
(*ref_cnt)++;
//loop_pa += mmu_info->pv_off;
*(mmu_l2 + l2_off) = (loop_pa | attr);
/* cache maintain */
rt_hw_cpu_dcache_clean(mmu_l2 + l2_off, 4);
loop_va += ARCH_PAGE_SIZE;
}
return 0;
err:
{
/* error, unmap and quit */
int i;
void *va, *pa;
va = (void*)((size_t)v_addr & ~ARCH_PAGE_MASK);
for (i = 0; i < npages; i++)
{
pa = rt_hw_mmu_v2p(mmu_info, va);
pa -= mmu_info->pv_off;
rt_pages_free(pa, 0);
va += ARCH_PAGE_SIZE;
}
__rt_hw_mmu_unmap(mmu_info, v_addr, npages);
return -1;
}
}
void *_rt_hw_mmu_map_auto(rt_mmu_info *mmu_info, void *v_addr, size_t size, size_t attr)
{
size_t vaddr;
size_t offset;
int pages;
int ret;
if (!size)
{
return 0;
}
offset = (size_t)v_addr & ARCH_PAGE_MASK;
size += (offset + ARCH_PAGE_SIZE - 1);
pages = (size >> ARCH_PAGE_SHIFT);
if (v_addr)
{
vaddr = (size_t)v_addr;
vaddr &= ~ARCH_PAGE_MASK;
if (check_vaddr(mmu_info, (void*)vaddr, pages) != 0)
{
return 0;
}
}
else
{
vaddr = find_vaddr(mmu_info, pages);
}
if (vaddr) {
ret = __rt_hw_mmu_map_auto(mmu_info, (void*)vaddr, pages, attr);
if (ret == 0)
{
rt_hw_cpu_tlb_invalidate();
return (void*)vaddr + offset;
}
}
return 0;
}
#endif
void _rt_hw_mmu_unmap(rt_mmu_info *mmu_info, void* v_addr, size_t size)
{
size_t va_s, va_e;
int pages;
va_s = (size_t)v_addr;
va_e = (size_t)v_addr + size - 1;
va_s >>= ARCH_PAGE_SHIFT;
va_e >>= ARCH_PAGE_SHIFT;
pages = va_e - va_s + 1;
__rt_hw_mmu_unmap(mmu_info, v_addr, pages);
rt_hw_cpu_tlb_invalidate();
}
//va --> pa
void *rt_hw_kernel_virt_to_phys(void *v_addr, size_t size)
{
void *p_addr = 0;
return p_addr;
}
//pa --> va
void *rt_hw_kernel_phys_to_virt(void *p_addr, size_t size)
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{
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void *v_addr = 0;
#ifdef RT_USING_USERSPACE
extern rt_mmu_info mmu_info;
v_addr = rt_hw_mmu_map(&mmu_info, 0, p_addr, size, MMU_MAP_K_RW);
#else
v_addr = p_addr;
#endif
return v_addr;
}
#ifdef RT_USING_USERSPACE
void *rt_hw_mmu_map(rt_mmu_info *mmu_info, void *v_addr, void* p_addr, size_t size, size_t attr)
{
void *ret;
rt_base_t level;
level = rt_hw_interrupt_disable();
ret = _rt_hw_mmu_map(mmu_info, v_addr, p_addr, size, attr);
rt_hw_interrupt_enable(level);
return ret;
}
void *rt_hw_mmu_map_auto(rt_mmu_info *mmu_info, void *v_addr, size_t size, size_t attr)
{
void *ret;
rt_base_t level;
level = rt_hw_interrupt_disable();
ret = _rt_hw_mmu_map_auto(mmu_info, v_addr, size, attr);
rt_hw_interrupt_enable(level);
return ret;
}
#endif
void rt_hw_mmu_unmap(rt_mmu_info *mmu_info, void* v_addr, size_t size)
{
rt_base_t level;
level = rt_hw_interrupt_disable();
_rt_hw_mmu_unmap(mmu_info, v_addr, size);
rt_hw_interrupt_enable(level);
}
void *_rt_hw_mmu_v2p(rt_mmu_info *mmu_info, void* v_addr)
{
size_t l1_off, l2_off;
size_t *mmu_l1, *mmu_l2;
size_t tmp;
size_t pa;
l1_off = (size_t)v_addr >> ARCH_SECTION_SHIFT;
if (!mmu_info)
{
return (void*)0;
}
mmu_l1 = (size_t*)mmu_info->vtable + l1_off;
tmp = *mmu_l1;
switch (tmp & ARCH_MMU_USED_MASK)
{
case 0: /* not used */
break;
case 1: /* page table */
mmu_l2 = (size_t *)((tmp & ~ARCH_PAGE_TBL_MASK) - mmu_info->pv_off);
l2_off = (((size_t)v_addr & ARCH_SECTION_MASK) >> ARCH_PAGE_SHIFT);
pa = *(mmu_l2 + l2_off);
if (pa & ARCH_MMU_USED_MASK)
{
if ((pa & ARCH_MMU_USED_MASK) == 1)
{
/* lage page, not support */
break;
}
pa &= ~(ARCH_PAGE_MASK);
pa += ((size_t)v_addr & ARCH_PAGE_MASK);
return (void*)pa;
}
break;
case 2:
case 3:
/* section */
if (tmp & ARCH_TYPE_SUPERSECTION)
{
/* super section, not support */
break;
}
pa = (tmp & ~ARCH_SECTION_MASK);
pa += ((size_t)v_addr & ARCH_SECTION_MASK);
return (void*)pa;
}
return (void*)0;
}
void *rt_hw_mmu_v2p(rt_mmu_info *mmu_info, void* v_addr)
{
void *ret;
rt_base_t level;
level = rt_hw_interrupt_disable();
ret = _rt_hw_mmu_v2p(mmu_info, v_addr);
rt_hw_interrupt_enable(level);
return ret;
}
#ifdef RT_USING_USERSPACE
void init_mm_setup(unsigned int *mtbl, unsigned int size, unsigned int pv_off) {
unsigned int va;
for (va = 0; va < 0x1000; va++) {
unsigned int vaddr = (va << 20);
if (vaddr >= KERNEL_VADDR_START && vaddr - KERNEL_VADDR_START < size) {
mtbl[va] = ((va << 20) + pv_off) | NORMAL_MEM;
} else if (vaddr >= (KERNEL_VADDR_START + pv_off) && vaddr - (KERNEL_VADDR_START + pv_off) < size) {
mtbl[va] = (va << 20) | NORMAL_MEM;
} else {
mtbl[va] = 0;
}
}
}
#endif