Currently, it does a cntlzd on the size and then subtracts it from 21.... this doesn't take into account the varying size of a "long". Just use __ilog instead (and subtract the 10 we have to subtract to get to the tsize encoding). Also correct the comment about page sizes supported. Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
		
			
				
	
	
		
			237 lines
		
	
	
	
		
			6.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			237 lines
		
	
	
	
		
			6.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Modifications by Kumar Gala (galak@kernel.crashing.org) to support
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 * E500 Book E processors.
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 *
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 * Copyright 2004,2010 Freescale Semiconductor, Inc.
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 *
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 * This file contains the routines for initializing the MMU
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 * on the 4xx series of chips.
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 *  -- paulus
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 *
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 *  Derived from arch/ppc/mm/init.c:
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 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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 *
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 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
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 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
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 *    Copyright (C) 1996 Paul Mackerras
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 *
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 *  Derived from "arch/i386/mm/init.c"
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 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
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 *
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 *  This program is free software; you can redistribute it and/or
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 *  modify it under the terms of the GNU General Public License
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 *  as published by the Free Software Foundation; either version
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 *  2 of the License, or (at your option) any later version.
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 *
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 */
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#include <linux/signal.h>
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/string.h>
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#include <linux/types.h>
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#include <linux/ptrace.h>
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#include <linux/mman.h>
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#include <linux/mm.h>
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#include <linux/swap.h>
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#include <linux/stddef.h>
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#include <linux/vmalloc.h>
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#include <linux/init.h>
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#include <linux/delay.h>
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#include <linux/highmem.h>
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#include <linux/memblock.h>
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#include <asm/pgalloc.h>
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#include <asm/prom.h>
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#include <asm/io.h>
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#include <asm/mmu_context.h>
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#include <asm/pgtable.h>
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#include <asm/mmu.h>
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#include <asm/uaccess.h>
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#include <asm/smp.h>
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#include <asm/machdep.h>
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#include <asm/setup.h>
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#include "mmu_decl.h"
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unsigned int tlbcam_index;
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#define NUM_TLBCAMS	(64)
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struct tlbcam TLBCAM[NUM_TLBCAMS];
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struct tlbcamrange {
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	unsigned long start;
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	unsigned long limit;
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	phys_addr_t phys;
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} tlbcam_addrs[NUM_TLBCAMS];
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extern unsigned int tlbcam_index;
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unsigned long tlbcam_sz(int idx)
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{
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	return tlbcam_addrs[idx].limit - tlbcam_addrs[idx].start + 1;
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}
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/*
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 * Return PA for this VA if it is mapped by a CAM, or 0
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 */
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phys_addr_t v_mapped_by_tlbcam(unsigned long va)
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{
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	int b;
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	for (b = 0; b < tlbcam_index; ++b)
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		if (va >= tlbcam_addrs[b].start && va < tlbcam_addrs[b].limit)
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			return tlbcam_addrs[b].phys + (va - tlbcam_addrs[b].start);
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	return 0;
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}
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/*
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 * Return VA for a given PA or 0 if not mapped
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 */
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unsigned long p_mapped_by_tlbcam(phys_addr_t pa)
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{
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	int b;
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	for (b = 0; b < tlbcam_index; ++b)
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		if (pa >= tlbcam_addrs[b].phys
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			&& pa < (tlbcam_addrs[b].limit-tlbcam_addrs[b].start)
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		              +tlbcam_addrs[b].phys)
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			return tlbcam_addrs[b].start+(pa-tlbcam_addrs[b].phys);
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	return 0;
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}
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/*
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 * Set up a variable-size TLB entry (tlbcam). The parameters are not checked;
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 * in particular size must be a power of 4 between 4k and the max supported by
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 * an implementation; max may further be limited by what can be represented in
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 * an unsigned long (for example, 32-bit implementations cannot support a 4GB
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 * size).
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 */
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static void settlbcam(int index, unsigned long virt, phys_addr_t phys,
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		unsigned long size, unsigned long flags, unsigned int pid)
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{
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	unsigned int tsize;
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	tsize = __ilog2(size) - 10;
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#ifdef CONFIG_SMP
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	if ((flags & _PAGE_NO_CACHE) == 0)
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		flags |= _PAGE_COHERENT;
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#endif
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	TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index) | MAS0_NV(index+1);
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	TLBCAM[index].MAS1 = MAS1_VALID | MAS1_IPROT | MAS1_TSIZE(tsize) | MAS1_TID(pid);
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	TLBCAM[index].MAS2 = virt & PAGE_MASK;
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	TLBCAM[index].MAS2 |= (flags & _PAGE_WRITETHRU) ? MAS2_W : 0;
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	TLBCAM[index].MAS2 |= (flags & _PAGE_NO_CACHE) ? MAS2_I : 0;
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	TLBCAM[index].MAS2 |= (flags & _PAGE_COHERENT) ? MAS2_M : 0;
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	TLBCAM[index].MAS2 |= (flags & _PAGE_GUARDED) ? MAS2_G : 0;
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	TLBCAM[index].MAS2 |= (flags & _PAGE_ENDIAN) ? MAS2_E : 0;
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	TLBCAM[index].MAS3 = (phys & MAS3_RPN) | MAS3_SX | MAS3_SR;
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	TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_SW : 0);
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	if (mmu_has_feature(MMU_FTR_BIG_PHYS))
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		TLBCAM[index].MAS7 = (u64)phys >> 32;
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	/* Below is unlikely -- only for large user pages or similar */
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	if (pte_user(flags)) {
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	   TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR;
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	   TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0);
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	}
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	tlbcam_addrs[index].start = virt;
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	tlbcam_addrs[index].limit = virt + size - 1;
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	tlbcam_addrs[index].phys = phys;
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	loadcam_entry(index);
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}
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unsigned long calc_cam_sz(unsigned long ram, unsigned long virt,
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			  phys_addr_t phys)
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{
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	unsigned int camsize = __ilog2(ram) & ~1U;
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	unsigned int align = __ffs(virt | phys) & ~1U;
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	unsigned long max_cam = (mfspr(SPRN_TLB1CFG) >> 16) & 0xf;
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	/* Convert (4^max) kB to (2^max) bytes */
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	max_cam = max_cam * 2 + 10;
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	if (camsize > align)
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		camsize = align;
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	if (camsize > max_cam)
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		camsize = max_cam;
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	return 1UL << camsize;
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}
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unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx)
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{
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	int i;
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	unsigned long virt = PAGE_OFFSET;
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	phys_addr_t phys = memstart_addr;
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	unsigned long amount_mapped = 0;
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	/* Calculate CAM values */
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	for (i = 0; ram && i < max_cam_idx; i++) {
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		unsigned long cam_sz;
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		cam_sz = calc_cam_sz(ram, virt, phys);
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		settlbcam(i, virt, phys, cam_sz, PAGE_KERNEL_X, 0);
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		ram -= cam_sz;
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		amount_mapped += cam_sz;
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		virt += cam_sz;
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		phys += cam_sz;
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	}
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	tlbcam_index = i;
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	return amount_mapped;
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}
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#ifdef CONFIG_PPC32
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#if defined(CONFIG_LOWMEM_CAM_NUM_BOOL) && (CONFIG_LOWMEM_CAM_NUM >= NUM_TLBCAMS)
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#error "LOWMEM_CAM_NUM must be less than NUM_TLBCAMS"
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#endif
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unsigned long __init mmu_mapin_ram(unsigned long top)
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{
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	return tlbcam_addrs[tlbcam_index - 1].limit - PAGE_OFFSET + 1;
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}
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/*
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 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
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 */
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void __init MMU_init_hw(void)
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{
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	flush_instruction_cache();
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}
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void __init adjust_total_lowmem(void)
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{
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	unsigned long ram;
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	int i;
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	/* adjust lowmem size to __max_low_memory */
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	ram = min((phys_addr_t)__max_low_memory, (phys_addr_t)total_lowmem);
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	__max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM);
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	pr_info("Memory CAM mapping: ");
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	for (i = 0; i < tlbcam_index - 1; i++)
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		pr_cont("%lu/", tlbcam_sz(i) >> 20);
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	pr_cont("%lu Mb, residual: %dMb\n", tlbcam_sz(tlbcam_index - 1) >> 20,
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	        (unsigned int)((total_lowmem - __max_low_memory) >> 20));
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	memblock_set_current_limit(memstart_addr + __max_low_memory);
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}
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void setup_initial_memory_limit(phys_addr_t first_memblock_base,
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				phys_addr_t first_memblock_size)
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{
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	phys_addr_t limit = first_memblock_base + first_memblock_size;
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	/* 64M mapped initially according to head_fsl_booke.S */
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	memblock_set_current_limit(min_t(u64, limit, 0x04000000));
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}
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#endif
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