/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "mmu_decl.h" unsigned int tlbcam_index; #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; /* Below is unlikely -- only for large user pages or similar */ if (pte_user(flags)) { 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; } #ifdef CONFIG_PPC32 #if defined(CONFIG_LOWMEM_CAM_NUM_BOOL) && (CONFIG_LOWMEM_CAM_NUM >= NUM_TLBCAMS) #error "LOWMEM_CAM_NUM must be less than NUM_TLBCAMS" #endif 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)); } #endif