#include #include #include static unsigned long *ttb; void arm_create_section(unsigned long virt, unsigned long phys, int size_m, unsigned int flags) { int i; phys >>= 20; virt >>= 20; for (i = size_m; i > 0; i--, virt++, phys++) ttb[virt] = (phys << 20) | flags; asm volatile ( "mov r0, #0;" "mcr p15, 0, r0, c7, c6, 0;" /* flush d-cache */ "mcr p15, 0, r0, c8, c7, 0;" /* flush i+d-TLBs */ : : : "r0","memory" /* clobber list */ ); } /* * Prepare MMU for usage and create a flat mapping. Board * code is responsible to remap the SDRAM cached */ void mmu_init(void) { int i; ttb = xzalloc(0x8000); ttb = (void *)(((unsigned long)ttb + 0x4000) & ~0x3fff); /* Set the ttb register */ asm volatile ("mcr p15,0,%0,c2,c0,0" : : "r"(ttb) /*:*/); /* Set the Domain Access Control Register */ i = 0x3; asm volatile ("mcr p15,0,%0,c3,c0,0" : : "r"(i) /*:*/); /* create a flat mapping */ arm_create_section(0, 0, 4096, PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT); } /* * enable the MMU. Should be called after mmu_init() */ void mmu_enable(void) { asm volatile ( "bl __mmu_cache_on;" : : : "r0", "r1", "r2", "r3", "r6", "r10", "r12", "cc", "memory" ); } struct outer_cache_fns outer_cache; /* * Clean and invalide caches, disable MMU */ void mmu_disable(void) { if (outer_cache.disable) outer_cache.disable(); asm volatile ( "bl __mmu_cache_flush;" "bl __mmu_cache_off;" : : : "r0", "r1", "r2", "r3", "r6", "r10", "r12", "cc", "memory" ); } /* * For boards which need coherent memory for DMA. The idea * is simple: Setup a uncached section containing your SDRAM * and call setup_dma_coherent() with the offset between the * cached and the uncached section. dma_alloc_coherent() then * works using normal malloc but returns the corresponding * pointer in the uncached area. */ static unsigned long dma_coherent_offset; void setup_dma_coherent(unsigned long offset) { dma_coherent_offset = offset; } void *dma_alloc_coherent(size_t size) { void *mem; mem = memalign(4096, size); if (mem) return mem + dma_coherent_offset; return NULL; } unsigned long virt_to_phys(void *virt) { return (unsigned long)virt - dma_coherent_offset; } void *phys_to_virt(unsigned long phys) { return (void *)(phys + dma_coherent_offset); } void dma_free_coherent(void *mem) { free(mem - dma_coherent_offset); } void dma_clean_range(unsigned long start, unsigned long end) { if (outer_cache.clean_range) outer_cache.clean_range(start, end); __dma_clean_range(start, end); } void dma_flush_range(unsigned long start, unsigned long end) { if (outer_cache.flush_range) outer_cache.flush_range(start, end); __dma_flush_range(start, end); } void dma_inv_range(unsigned long start, unsigned long end) { if (outer_cache.inv_range) outer_cache.inv_range(start, end); __dma_inv_range(start, end); }