/* * 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 #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]; 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 the max supported by * an implementation; max may further be limited by what can be represented in * an unsigned long (for example, 32-bit implementations cannot support a 4GB * size). */ static void settlbcam(int index, unsigned long virt, phys_addr_t phys, unsigned long size, unsigned long flags, unsigned int pid) { unsigned int tsize; tsize = __ilog2(size) - 10; #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 calc_cam_sz(unsigned long ram, unsigned long virt, phys_addr_t phys) { unsigned int camsize = __ilog2(ram); unsigned int align = __ffs(virt | phys); unsigned long max_cam; if ((mfspr(SPRN_MMUCFG) & MMUCFG_MAVN) == MMUCFG_MAVN_V1) { /* Convert (4^max) kB to (2^max) bytes */ max_cam = ((mfspr(SPRN_TLB1CFG) >> 16) & 0xf) * 2 + 10; camsize &= ~1U; align &= ~1U; } else { /* Convert (2^max) kB to (2^max) bytes */ max_cam = __ilog2(mfspr(SPRN_TLB1PS)) + 10; } if (camsize > align) camsize = align; if (camsize > max_cam) camsize = max_cam; return 1UL << camsize; } static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt, unsigned long ram, int max_cam_idx) { int i; unsigned long amount_mapped = 0; /* Calculate CAM values */ for (i = 0; ram && i < max_cam_idx; i++) { unsigned long cam_sz; cam_sz = calc_cam_sz(ram, virt, phys); 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; #ifdef CONFIG_PPC64 get_paca()->tcd.esel_next = i; get_paca()->tcd.esel_max = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY; get_paca()->tcd.esel_first = i; #endif return amount_mapped; } unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx) { unsigned long virt = PAGE_OFFSET; phys_addr_t phys = memstart_addr; return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx); } #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); i = switch_to_as1(); __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM); restore_to_as0(i, 0, 0, 1); 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)); } #ifdef CONFIG_RELOCATABLE int __initdata is_second_reloc; notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start) { unsigned long base = KERNELBASE; kernstart_addr = start; if (is_second_reloc) { virt_phys_offset = PAGE_OFFSET - memstart_addr; return; } /* * Relocatable kernel support based on processing of dynamic * relocation entries. Before we get the real memstart_addr, * We will compute the virt_phys_offset like this: * virt_phys_offset = stext.run - kernstart_addr * * stext.run = (KERNELBASE & ~0x3ffffff) + * (kernstart_addr & 0x3ffffff) * When we relocate, we have : * * (kernstart_addr & 0x3ffffff) = (stext.run & 0x3ffffff) * * hence: * virt_phys_offset = (KERNELBASE & ~0x3ffffff) - * (kernstart_addr & ~0x3ffffff) * */ start &= ~0x3ffffff; base &= ~0x3ffffff; virt_phys_offset = base - start; early_get_first_memblock_info(__va(dt_ptr), NULL); /* * We now get the memstart_addr, then we should check if this * address is the same as what the PAGE_OFFSET map to now. If * not we have to change the map of PAGE_OFFSET to memstart_addr * and do a second relocation. */ if (start != memstart_addr) { int n; long offset = start - memstart_addr; is_second_reloc = 1; n = switch_to_as1(); /* map a 64M area for the second relocation */ if (memstart_addr > start) map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM); else map_mem_in_cams_addr(start, PAGE_OFFSET + offset, 0x4000000, CONFIG_LOWMEM_CAM_NUM); restore_to_as0(n, offset, __va(dt_ptr), 1); /* We should never reach here */ panic("Relocation error"); } } #endif #endif