| /* |
| * Modifications by Kumar Gala (galak@kernel.crashing.org) to support |
| * E500 Book E processors. |
| * |
| * Copyright 2004,2010 Freescale Semiconductor, Inc. |
| * |
| * This file contains the routines for initializing the MMU |
| * on the 4xx series of chips. |
| * -- paulus |
| * |
| * Derived from arch/ppc/mm/init.c: |
| * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) |
| * |
| * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) |
| * and Cort Dougan (PReP) (cort@cs.nmt.edu) |
| * Copyright (C) 1996 Paul Mackerras |
| * |
| * Derived from "arch/i386/mm/init.c" |
| * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
| * |
| * 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/signal.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/string.h> |
| #include <linux/types.h> |
| #include <linux/ptrace.h> |
| #include <linux/mman.h> |
| #include <linux/mm.h> |
| #include <linux/swap.h> |
| #include <linux/stddef.h> |
| #include <linux/vmalloc.h> |
| #include <linux/init.h> |
| #include <linux/delay.h> |
| #include <linux/highmem.h> |
| #include <linux/memblock.h> |
| |
| #include <asm/pgalloc.h> |
| #include <asm/prom.h> |
| #include <asm/io.h> |
| #include <asm/mmu_context.h> |
| #include <asm/pgtable.h> |
| #include <asm/mmu.h> |
| #include <asm/uaccess.h> |
| #include <asm/smp.h> |
| #include <asm/machdep.h> |
| #include <asm/setup.h> |
| |
| #include "mmu_decl.h" |
| |
| unsigned int tlbcam_index; |
| |
| |
| #if defined(CONFIG_LOWMEM_CAM_NUM_BOOL) && (CONFIG_LOWMEM_CAM_NUM >= NUM_TLBCAMS) |
| #error "LOWMEM_CAM_NUM must be less than NUM_TLBCAMS" |
| #endif |
| |
| #define NUM_TLBCAMS (64) |
| struct tlbcam TLBCAM[NUM_TLBCAMS]; |
| |
| struct tlbcamrange { |
| unsigned long start; |
| unsigned long limit; |
| phys_addr_t phys; |
| } tlbcam_addrs[NUM_TLBCAMS]; |
| |
| extern unsigned int tlbcam_index; |
| |
| unsigned long tlbcam_sz(int idx) |
| { |
| return tlbcam_addrs[idx].limit - tlbcam_addrs[idx].start + 1; |
| } |
| |
| /* |
| * Return PA for this VA if it is mapped by a CAM, or 0 |
| */ |
| phys_addr_t v_mapped_by_tlbcam(unsigned long va) |
| { |
| int b; |
| for (b = 0; b < tlbcam_index; ++b) |
| if (va >= tlbcam_addrs[b].start && va < tlbcam_addrs[b].limit) |
| return tlbcam_addrs[b].phys + (va - tlbcam_addrs[b].start); |
| return 0; |
| } |
| |
| /* |
| * Return VA for a given PA or 0 if not mapped |
| */ |
| unsigned long p_mapped_by_tlbcam(phys_addr_t pa) |
| { |
| int b; |
| for (b = 0; b < tlbcam_index; ++b) |
| if (pa >= tlbcam_addrs[b].phys |
| && pa < (tlbcam_addrs[b].limit-tlbcam_addrs[b].start) |
| +tlbcam_addrs[b].phys) |
| return tlbcam_addrs[b].start+(pa-tlbcam_addrs[b].phys); |
| return 0; |
| } |
| |
| /* |
| * Set up a variable-size TLB entry (tlbcam). The parameters are not checked; |
| * in particular size must be a power of 4 between 4k and 256M (or 1G, for cpus |
| * that support extended page sizes). Note that while some cpus support a |
| * page size of 4G, we don't allow its use here. |
| */ |
| static void settlbcam(int index, unsigned long virt, phys_addr_t phys, |
| unsigned long size, unsigned long flags, unsigned int pid) |
| { |
| unsigned int tsize, lz; |
| |
| asm (PPC_CNTLZL "%0,%1" : "=r" (lz) : "r" (size)); |
| tsize = 21 - lz; |
| |
| #ifdef CONFIG_SMP |
| if ((flags & _PAGE_NO_CACHE) == 0) |
| flags |= _PAGE_COHERENT; |
| #endif |
| |
| TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index) | MAS0_NV(index+1); |
| TLBCAM[index].MAS1 = MAS1_VALID | MAS1_IPROT | MAS1_TSIZE(tsize) | MAS1_TID(pid); |
| TLBCAM[index].MAS2 = virt & PAGE_MASK; |
| |
| TLBCAM[index].MAS2 |= (flags & _PAGE_WRITETHRU) ? MAS2_W : 0; |
| TLBCAM[index].MAS2 |= (flags & _PAGE_NO_CACHE) ? MAS2_I : 0; |
| TLBCAM[index].MAS2 |= (flags & _PAGE_COHERENT) ? MAS2_M : 0; |
| TLBCAM[index].MAS2 |= (flags & _PAGE_GUARDED) ? MAS2_G : 0; |
| TLBCAM[index].MAS2 |= (flags & _PAGE_ENDIAN) ? MAS2_E : 0; |
| |
| TLBCAM[index].MAS3 = (phys & MAS3_RPN) | MAS3_SX | MAS3_SR; |
| TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_SW : 0); |
| if (mmu_has_feature(MMU_FTR_BIG_PHYS)) |
| TLBCAM[index].MAS7 = (u64)phys >> 32; |
| |
| if (flags & _PAGE_USER) { |
| TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR; |
| TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0); |
| } |
| |
| tlbcam_addrs[index].start = virt; |
| tlbcam_addrs[index].limit = virt + size - 1; |
| tlbcam_addrs[index].phys = phys; |
| |
| loadcam_entry(index); |
| } |
| |
| unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx) |
| { |
| int i; |
| unsigned long virt = PAGE_OFFSET; |
| phys_addr_t phys = memstart_addr; |
| unsigned long amount_mapped = 0; |
| unsigned long max_cam = (mfspr(SPRN_TLB1CFG) >> 16) & 0xf; |
| |
| /* Convert (4^max) kB to (2^max) bytes */ |
| max_cam = max_cam * 2 + 10; |
| |
| /* Calculate CAM values */ |
| for (i = 0; ram && i < max_cam_idx; i++) { |
| unsigned int camsize = __ilog2(ram) & ~1U; |
| unsigned int align = __ffs(virt | phys) & ~1U; |
| unsigned long cam_sz; |
| |
| if (camsize > align) |
| camsize = align; |
| if (camsize > max_cam) |
| camsize = max_cam; |
| |
| cam_sz = 1UL << camsize; |
| settlbcam(i, virt, phys, cam_sz, PAGE_KERNEL_X, 0); |
| |
| ram -= cam_sz; |
| amount_mapped += cam_sz; |
| virt += cam_sz; |
| phys += cam_sz; |
| } |
| tlbcam_index = i; |
| |
| return amount_mapped; |
| } |
| |
| unsigned long __init mmu_mapin_ram(unsigned long top) |
| { |
| return tlbcam_addrs[tlbcam_index - 1].limit - PAGE_OFFSET + 1; |
| } |
| |
| /* |
| * MMU_init_hw does the chip-specific initialization of the MMU hardware. |
| */ |
| void __init MMU_init_hw(void) |
| { |
| flush_instruction_cache(); |
| } |
| |
| void __init adjust_total_lowmem(void) |
| { |
| unsigned long ram; |
| int i; |
| |
| /* adjust lowmem size to __max_low_memory */ |
| ram = min((phys_addr_t)__max_low_memory, (phys_addr_t)total_lowmem); |
| |
| __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM); |
| |
| pr_info("Memory CAM mapping: "); |
| for (i = 0; i < tlbcam_index - 1; i++) |
| pr_cont("%lu/", tlbcam_sz(i) >> 20); |
| pr_cont("%lu Mb, residual: %dMb\n", tlbcam_sz(tlbcam_index - 1) >> 20, |
| (unsigned int)((total_lowmem - __max_low_memory) >> 20)); |
| |
| memblock_set_current_limit(memstart_addr + __max_low_memory); |
| } |
| |
| void setup_initial_memory_limit(phys_addr_t first_memblock_base, |
| phys_addr_t first_memblock_size) |
| { |
| phys_addr_t limit = first_memblock_base + first_memblock_size; |
| |
| /* 64M mapped initially according to head_fsl_booke.S */ |
| memblock_set_current_limit(min_t(u64, limit, 0x04000000)); |
| } |