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	Prefix mmu.h PAGE_xxx definitions with MMU_ in order to prevent a naming conflict with other definitions. Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
		
			
				
	
	
		
			79 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			79 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <common.h>
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| #include <asm/arch/mmu.h>
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| #include <asm/sysreg.h>
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| 
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| void mmu_init_r(unsigned long dest_addr)
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| {
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| 	uintptr_t	vmr_table_addr;
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| 
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| 	/* Round monitor address down to the nearest page boundary */
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| 	dest_addr &= MMU_PAGE_ADDR_MASK;
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| 
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| 	/* Initialize TLB entry 0 to cover the monitor, and lock it */
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| 	sysreg_write(TLBEHI, dest_addr | SYSREG_BIT(TLBEHI_V));
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| 	sysreg_write(TLBELO, dest_addr | MMU_VMR_CACHE_WRBACK);
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| 	sysreg_write(MMUCR, SYSREG_BF(DRP, 0) | SYSREG_BF(DLA, 1)
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| 			| SYSREG_BIT(MMUCR_S) | SYSREG_BIT(M));
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| 	__builtin_tlbw();
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| 
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| 	/*
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| 	 * Calculate the address of the VM range table in a PC-relative
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| 	 * manner to make sure we hit the SDRAM and not the flash.
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| 	 */
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| 	vmr_table_addr = (uintptr_t)&mmu_vmr_table;
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| 	sysreg_write(PTBR, vmr_table_addr);
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| 	printf("VMR table @ 0x%08lx\n", vmr_table_addr);
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| 
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| 	/* Enable paging */
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| 	sysreg_write(MMUCR, SYSREG_BF(DRP, 1) | SYSREG_BF(DLA, 1)
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| 			| SYSREG_BIT(MMUCR_S) | SYSREG_BIT(M) | SYSREG_BIT(E));
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| }
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| 
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| int mmu_handle_tlb_miss(void)
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| {
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| 	const struct mmu_vm_range *vmr_table;
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| 	const struct mmu_vm_range *vmr;
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| 	unsigned int fault_pgno;
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| 	int first, last;
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| 
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| 	fault_pgno = sysreg_read(TLBEAR) >> MMU_PAGE_SHIFT;
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| 	vmr_table = (const struct mmu_vm_range *)sysreg_read(PTBR);
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| 
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| 	/* Do a binary search through the VM ranges */
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| 	first = 0;
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| 	last = CONFIG_SYS_NR_VM_REGIONS;
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| 	while (first < last) {
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| 		unsigned int start;
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| 		int middle;
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| 
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| 		/* Pick the entry in the middle of the remaining range */
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| 		middle = (first + last) >> 1;
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| 		vmr = &vmr_table[middle];
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| 		start = vmr->virt_pgno;
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| 
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| 		/* Do the bisection thing */
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| 		if (fault_pgno < start) {
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| 			last = middle;
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| 		} else if (fault_pgno >= (start + vmr->nr_pages)) {
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| 			first = middle + 1;
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| 		} else {
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| 			/* Got it; let's slam it into the TLB */
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| 			uint32_t tlbelo;
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| 
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| 			tlbelo = vmr->phys & ~MMU_PAGE_ADDR_MASK;
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| 			tlbelo |= fault_pgno << MMU_PAGE_SHIFT;
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| 			sysreg_write(TLBELO, tlbelo);
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| 			__builtin_tlbw();
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| 
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| 			/* Zero means success */
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| 			return 0;
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| 		}
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| 	}
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| 
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| 	/*
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| 	 * Didn't find any matching entries. Return a nonzero value to
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| 	 * indicate that this should be treated as a fatal exception.
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| 	 */
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| 	return -1;
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| }
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