2 * Modifications by Kumar Gala (galak@kernel.crashing.org) to support
3 * E500 Book E processors.
5 * Copyright 2004 Freescale Semiconductor, Inc
7 * This file contains the routines for initializing the MMU
8 * on the 4xx series of chips.
11 * Derived from arch/ppc/mm/init.c:
12 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
14 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
15 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
16 * Copyright (C) 1996 Paul Mackerras
18 * Derived from "arch/i386/mm/init.c"
19 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
21 * This program is free software; you can redistribute it and/or
22 * modify it under the terms of the GNU General Public License
23 * as published by the Free Software Foundation; either version
24 * 2 of the License, or (at your option) any later version.
28 #include <linux/signal.h>
29 #include <linux/sched.h>
30 #include <linux/kernel.h>
31 #include <linux/errno.h>
32 #include <linux/string.h>
33 #include <linux/types.h>
34 #include <linux/ptrace.h>
35 #include <linux/mman.h>
37 #include <linux/swap.h>
38 #include <linux/stddef.h>
39 #include <linux/vmalloc.h>
40 #include <linux/init.h>
41 #include <linux/delay.h>
42 #include <linux/highmem.h>
44 #include <asm/pgalloc.h>
47 #include <asm/mmu_context.h>
48 #include <asm/pgtable.h>
50 #include <asm/uaccess.h>
52 #include <asm/machdep.h>
53 #include <asm/setup.h>
57 extern void loadcam_entry(unsigned int index
);
58 unsigned int tlbcam_index
;
59 static unsigned long __cam0
, __cam1
, __cam2
;
61 #define NUM_TLBCAMS (16)
63 struct tlbcam TLBCAM
[NUM_TLBCAMS
];
69 } tlbcam_addrs
[NUM_TLBCAMS
];
71 extern unsigned int tlbcam_index
;
74 * Return PA for this VA if it is mapped by a CAM, or 0
76 unsigned long v_mapped_by_tlbcam(unsigned long va
)
79 for (b
= 0; b
< tlbcam_index
; ++b
)
80 if (va
>= tlbcam_addrs
[b
].start
&& va
< tlbcam_addrs
[b
].limit
)
81 return tlbcam_addrs
[b
].phys
+ (va
- tlbcam_addrs
[b
].start
);
86 * Return VA for a given PA or 0 if not mapped
88 unsigned long p_mapped_by_tlbcam(unsigned long pa
)
91 for (b
= 0; b
< tlbcam_index
; ++b
)
92 if (pa
>= tlbcam_addrs
[b
].phys
93 && pa
< (tlbcam_addrs
[b
].limit
-tlbcam_addrs
[b
].start
)
94 +tlbcam_addrs
[b
].phys
)
95 return tlbcam_addrs
[b
].start
+(pa
-tlbcam_addrs
[b
].phys
);
100 * Set up one of the I/D BAT (block address translation) register pairs.
101 * The parameters are not checked; in particular size must be a power
102 * of 4 between 4k and 256M.
104 void settlbcam(int index
, unsigned long virt
, phys_addr_t phys
,
105 unsigned int size
, int flags
, unsigned int pid
)
107 unsigned int tsize
, lz
;
109 asm ("cntlzw %0,%1" : "=r" (lz
) : "r" (size
));
110 tsize
= (21 - lz
) / 2;
113 if ((flags
& _PAGE_NO_CACHE
) == 0)
114 flags
|= _PAGE_COHERENT
;
117 TLBCAM
[index
].MAS0
= MAS0_TLBSEL(1) | MAS0_ESEL(index
) | MAS0_NV(index
+1);
118 TLBCAM
[index
].MAS1
= MAS1_VALID
| MAS1_IPROT
| MAS1_TSIZE(tsize
) | MAS1_TID(pid
);
119 TLBCAM
[index
].MAS2
= virt
& PAGE_MASK
;
121 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_WRITETHRU
) ? MAS2_W
: 0;
122 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_NO_CACHE
) ? MAS2_I
: 0;
123 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_COHERENT
) ? MAS2_M
: 0;
124 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_GUARDED
) ? MAS2_G
: 0;
125 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_ENDIAN
) ? MAS2_E
: 0;
127 TLBCAM
[index
].MAS3
= (phys
& PAGE_MASK
) | MAS3_SX
| MAS3_SR
;
128 TLBCAM
[index
].MAS3
|= ((flags
& _PAGE_RW
) ? MAS3_SW
: 0);
130 #ifndef CONFIG_KGDB /* want user access for breakpoints */
131 if (flags
& _PAGE_USER
) {
132 TLBCAM
[index
].MAS3
|= MAS3_UX
| MAS3_UR
;
133 TLBCAM
[index
].MAS3
|= ((flags
& _PAGE_RW
) ? MAS3_UW
: 0);
136 TLBCAM
[index
].MAS3
|= MAS3_UX
| MAS3_UR
;
137 TLBCAM
[index
].MAS3
|= ((flags
& _PAGE_RW
) ? MAS3_UW
: 0);
140 tlbcam_addrs
[index
].start
= virt
;
141 tlbcam_addrs
[index
].limit
= virt
+ size
- 1;
142 tlbcam_addrs
[index
].phys
= phys
;
144 loadcam_entry(index
);
147 void invalidate_tlbcam_entry(int index
)
149 TLBCAM
[index
].MAS0
= MAS0_TLBSEL(1) | MAS0_ESEL(index
);
150 TLBCAM
[index
].MAS1
= ~MAS1_VALID
;
152 loadcam_entry(index
);
155 void __init
cam_mapin_ram(unsigned long cam0
, unsigned long cam1
,
158 settlbcam(0, PAGE_OFFSET
, memstart_addr
, cam0
, _PAGE_KERNEL
, 0);
162 settlbcam(1, PAGE_OFFSET
+cam0
, memstart_addr
+cam0
, cam1
, _PAGE_KERNEL
, 0);
166 settlbcam(2, PAGE_OFFSET
+cam0
+cam1
, memstart_addr
+cam0
+cam1
, cam2
, _PAGE_KERNEL
, 0);
171 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
173 void __init
MMU_init_hw(void)
175 flush_instruction_cache();
178 unsigned long __init
mmu_mapin_ram(void)
180 cam_mapin_ram(__cam0
, __cam1
, __cam2
);
182 return __cam0
+ __cam1
+ __cam2
;
187 adjust_total_lowmem(void)
189 phys_addr_t max_lowmem_size
= __max_low_memory
;
190 phys_addr_t cam_max_size
= 0x10000000;
193 /* adjust CAM size to max_lowmem_size */
194 if (max_lowmem_size
< cam_max_size
)
195 cam_max_size
= max_lowmem_size
;
197 /* adjust lowmem size to max_lowmem_size */
198 ram
= min(max_lowmem_size
, total_lowmem
);
200 /* Calculate CAM values */
201 __cam0
= 1UL << 2 * (__ilog2(ram
) / 2);
202 if (__cam0
> cam_max_size
)
203 __cam0
= cam_max_size
;
206 __cam1
= 1UL << 2 * (__ilog2(ram
) / 2);
207 if (__cam1
> cam_max_size
)
208 __cam1
= cam_max_size
;
212 __cam2
= 1UL << 2 * (__ilog2(ram
) / 2);
213 if (__cam2
> cam_max_size
)
214 __cam2
= cam_max_size
;
218 printk(KERN_INFO
"Memory CAM mapping: CAM0=%ldMb, CAM1=%ldMb,"
219 " CAM2=%ldMb residual: %ldMb\n",
220 __cam0
>> 20, __cam1
>> 20, __cam2
>> 20,
221 (long int)((total_lowmem
- __cam0
- __cam1
- __cam2
)
223 __max_low_memory
= __cam0
+ __cam1
+ __cam2
;
224 __initial_memory_limit_addr
= memstart_addr
+ __max_low_memory
;