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Release 4.14 arch/powerpc/mm/8xx_mmu.c

Directory: arch/powerpc/mm
/*
 * This file contains the routines for initializing the MMU
 * on the 8xx series of chips.
 *  -- christophe
 *
 *  Derived from arch/powerpc/mm/40x_mmu.c:
 *
 *  This program 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
 *  2 of the License, or (at your option) any later version.
 *
 */

#include <linux/memblock.h>
#include <asm/fixmap.h>
#include <asm/code-patching.h>

#include "mmu_decl.h"


#define IMMR_SIZE (FIX_IMMR_SIZE << PAGE_SHIFT)

extern int __map_without_ltlbs;


static unsigned long block_mapped_ram;

/*
 * Return PA for this VA if it is in an area mapped with LTLBs.
 * Otherwise, returns 0
 */

phys_addr_t v_block_mapped(unsigned long va) { unsigned long p = PHYS_IMMR_BASE; if (__map_without_ltlbs) return 0; if (va >= VIRT_IMMR_BASE && va < VIRT_IMMR_BASE + IMMR_SIZE) return p + va - VIRT_IMMR_BASE; if (va >= PAGE_OFFSET && va < PAGE_OFFSET + block_mapped_ram) return __pa(va); return 0; }

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Christophe Leroy62100.00%2100.00%
Total62100.00%2100.00%

/* * Return VA for a given PA mapped with LTLBs or 0 if not mapped */
unsigned long p_block_mapped(phys_addr_t pa) { unsigned long p = PHYS_IMMR_BASE; if (__map_without_ltlbs) return 0; if (pa >= p && pa < p + IMMR_SIZE) return VIRT_IMMR_BASE + pa - p; if (pa < block_mapped_ram) return (unsigned long)__va(pa); return 0; }

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Christophe Leroy60100.00%2100.00%
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#define LARGE_PAGE_SIZE_8M (1<<23) /* * MMU_init_hw does the chip-specific initialization of the MMU hardware. */
void __init MMU_init_hw(void) { /* PIN up to the 3 first 8Mb after IMMR in DTLB table */ #ifdef CONFIG_PIN_TLB_DATA unsigned long ctr = mfspr(SPRN_MD_CTR) & 0xfe000000; unsigned long flags = 0xf0 | MD_SPS16K | _PAGE_SHARED | _PAGE_DIRTY; #ifdef CONFIG_PIN_TLB_IMMR int i = 29; #else int i = 28; #endif unsigned long addr = 0; unsigned long mem = total_lowmem; for (; i < 32 && mem >= LARGE_PAGE_SIZE_8M; i++) { mtspr(SPRN_MD_CTR, ctr | (i << 8)); mtspr(SPRN_MD_EPN, (unsigned long)__va(addr) | MD_EVALID); mtspr(SPRN_MD_TWC, MD_PS8MEG | MD_SVALID); mtspr(SPRN_MD_RPN, addr | flags | _PAGE_PRESENT); addr += LARGE_PAGE_SIZE_8M; mem -= LARGE_PAGE_SIZE_8M; } #endif }

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Christophe Leroy139100.00%4100.00%
Total139100.00%4100.00%


static void __init mmu_mapin_immr(void) { unsigned long p = PHYS_IMMR_BASE; unsigned long v = VIRT_IMMR_BASE; unsigned long f = pgprot_val(PAGE_KERNEL_NCG); int offset; for (offset = 0; offset < IMMR_SIZE; offset += PAGE_SIZE) map_kernel_page(v + offset, p + offset, f); }

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Christophe Leroy60100.00%3100.00%
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/* Address of instructions to patch */ #ifndef CONFIG_PIN_TLB_IMMR extern unsigned int DTLBMiss_jmp; #endif extern unsigned int DTLBMiss_cmp, FixupDAR_cmp; #ifndef CONFIG_PIN_TLB_TEXT extern unsigned int ITLBMiss_cmp; #endif
static void __init mmu_patch_cmp_limit(unsigned int *addr, unsigned long mapped) { unsigned int instr = *addr; instr &= 0xffff0000; instr |= (unsigned long)__va(mapped) >> 16; patch_instruction(addr, instr); }

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Christophe Leroy47100.00%2100.00%
Total47100.00%2100.00%


unsigned long __init mmu_mapin_ram(unsigned long top) { unsigned long mapped; if (__map_without_ltlbs) { mapped = 0; mmu_mapin_immr(); #ifndef CONFIG_PIN_TLB_IMMR patch_instruction(&DTLBMiss_jmp, PPC_INST_NOP); #endif #ifndef CONFIG_PIN_TLB_TEXT mmu_patch_cmp_limit(&ITLBMiss_cmp, 0); #endif } else { mapped = top & ~(LARGE_PAGE_SIZE_8M - 1); } mmu_patch_cmp_limit(&DTLBMiss_cmp, mapped); mmu_patch_cmp_limit(&FixupDAR_cmp, mapped); /* If the size of RAM is not an exact power of two, we may not * have covered RAM in its entirety with 8 MiB * pages. Consequently, restrict the top end of RAM currently * allocable so that calls to the MEMBLOCK to allocate PTEs for "tail" * coverage with normal-sized pages (or other reasons) do not * attempt to allocate outside the allowed range. */ if (mapped) memblock_set_current_limit(mapped); block_mapped_ram = mapped; return mapped; }

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Christophe Leroy101100.00%6100.00%
Total101100.00%6100.00%


void __init setup_initial_memory_limit(phys_addr_t first_memblock_base, phys_addr_t first_memblock_size) { /* We don't currently support the first MEMBLOCK not mapping 0 * physical on those processors */ BUG_ON(first_memblock_base != 0); /* 8xx can only access 24MB at the moment */ memblock_set_current_limit(min_t(u64, first_memblock_size, 0x01800000)); }

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Christophe Leroy33100.00%2100.00%
Total33100.00%2100.00%

/* * Set up to use a given MMU context. * id is context number, pgd is PGD pointer. * * We place the physical address of the new task page directory loaded * into the MMU base register, and set the ASID compare register with * the new "context." */
void set_context(unsigned long id, pgd_t *pgd) { s16 offset = (s16)(__pa(swapper_pg_dir)); #ifdef CONFIG_BDI_SWITCH pgd_t **ptr = *(pgd_t ***)(KERNELBASE + 0xf0); /* Context switch the PTE pointer for the Abatron BDI2000. * The PGDIR is passed as second argument. */ *(ptr + 1) = pgd; #endif /* Register M_TW will contain base address of level 1 table minus the * lower part of the kernel PGDIR base address, so that all accesses to * level 1 table are done relative to lower part of kernel PGDIR base * address. */ mtspr(SPRN_M_TW, __pa(pgd) - offset); /* Update context */ mtspr(SPRN_M_CASID, id); /* sync */ mb(); }

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Christophe Leroy84100.00%1100.00%
Total84100.00%1100.00%


void flush_instruction_cache(void) { isync(); mtspr(SPRN_IC_CST, IDC_INVALL); isync(); }

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Christophe Leroy20100.00%1100.00%
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Christophe Leroy668100.00%12100.00%
Total668100.00%12100.00%
Directory: arch/powerpc/mm
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