aboutsummaryrefslogtreecommitdiff
path: root/arch/ppc/mm/fsl_booke_mmu.c
blob: 36233bdcdf8ff7590b64941ef05430851a18a1d6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
/*
 * Modifications by Kumar Gala (kumar.gala@freescale.com) 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/bootmem.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

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);
	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;
}