/*
* 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 <asm/paca.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];
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, pgprot_val(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