/* * Modifications by Kumar Gala (galak@kernel.crashing.org) to support * E500 Book E processors. * * Copyright 2004 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 * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). * * 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/config.h> #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 <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/bootx.h> #include <asm/machdep.h> #include <asm/setup.h> extern void loadcam_entry(unsigned int index); unsigned int tlbcam_index; unsigned int num_tlbcam_entries; static unsigned long __cam0, __cam1, __cam2; extern unsigned long total_lowmem; extern unsigned long __max_low_memory; #define MAX_LOW_MEM CONFIG_LOWMEM_SIZE #define NUM_TLBCAMS (16) struct tlbcam { u32 MAS0; u32 MAS1; u32 MAS2; u32 MAS3; u32 MAS7; } TLBCAM[NUM_TLBCAMS]; struct tlbcamrange { unsigned long start; unsigned long limit; phys_addr_t phys; } tlbcam_addrs[NUM_TLBCAMS]; extern unsigned int tlbcam_index; /* * Return PA for this VA if it is mapped by a CAM, or 0 */ unsigned long 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(unsigned long 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 one of the I/D BAT (block address translation) register pairs. * The parameters are not checked; in particular size must be a power * of 4 between 4k and 256M. */ void settlbcam(int index, unsigned long virt, phys_addr_t phys, unsigned int size, int flags, unsigned int pid) { unsigned int tsize, lz; asm ("cntlzw %0,%1" : "=r" (lz) : "r" (size)); tsize = (21 - lz) / 2; #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 & PAGE_MASK) | MAS3_SX | MAS3_SR; TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_SW : 0); #ifndef CONFIG_KGDB /* want user access for breakpoints */ if (flags & _PAGE_USER) { TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR; TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0); } #else TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR; TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0); #endif tlbcam_addrs[index].start = virt; tlbcam_addrs[index].limit = virt + size - 1; tlbcam_addrs[index].phys = phys; loadcam_entry(index); } void invalidate_tlbcam_entry(int index) { TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index); TLBCAM[index].MAS1 = ~MAS1_VALID; loadcam_entry(index); } void __init cam_mapin_ram(unsigned long cam0, unsigned long cam1, unsigned long cam2) { settlbcam(0, KERNELBASE, PPC_MEMSTART, cam0, _PAGE_KERNEL, 0); tlbcam_index++; if (cam1) { tlbcam_index++; settlbcam(1, KERNELBASE+cam0, PPC_MEMSTART+cam0, cam1, _PAGE_KERNEL, 0); } if (cam2) { tlbcam_index++; settlbcam(2, KERNELBASE+cam0+cam1, PPC_MEMSTART+cam0+cam1, cam2, _PAGE_KERNEL, 0); } } /* * MMU_init_hw does the chip-specific initialization of the MMU hardware. */ void __init MMU_init_hw(void) { flush_instruction_cache(); } unsigned long __init mmu_mapin_ram(void) { cam_mapin_ram(__cam0, __cam1, __cam2); return __cam0 + __cam1 + __cam2; } void __init adjust_total_lowmem(void) { unsigned long max_low_mem = MAX_LOW_MEM; unsigned long cam_max = 0x10000000; unsigned long ram; /* adjust CAM size to max_low_mem */ if (max_low_mem < cam_max) cam_max = max_low_mem; /* adjust lowmem size to max_low_mem */ if (max_low_mem < total_lowmem) ram = max_low_mem; else ram = total_lowmem; /* Calculate CAM values */ __cam0 = 1UL << 2 * (__ilog2(ram) / 2); if (__cam0 > cam_max) __cam0 = cam_max; ram -= __cam0; if (ram) { __cam1 = 1UL << 2 * (__ilog2(ram) / 2); if (__cam1 > cam_max) __cam1 = cam_max; ram -= __cam1; } if (ram) { __cam2 = 1UL << 2 * (__ilog2(ram) / 2); if (__cam2 > cam_max) __cam2 = cam_max; ram -= __cam2; } printk(KERN_INFO "Memory CAM mapping: CAM0=%ldMb, CAM1=%ldMb," " CAM2=%ldMb residual: %ldMb\n", __cam0 >> 20, __cam1 >> 20, __cam2 >> 20, (total_lowmem - __cam0 - __cam1 - __cam2) >> 20); __max_low_memory = max_low_mem = __cam0 + __cam1 + __cam2; }