/*
* 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;
#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
