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 unsigned int tlbcam_index
;
59 #define NUM_TLBCAMS (64)
61 #if defined(CONFIG_LOWMEM_CAM_NUM_BOOL) && (CONFIG_LOWMEM_CAM_NUM >= NUM_TLBCAMS)
62 #error "LOWMEM_CAM_NUM must be less than NUM_TLBCAMS"
71 } TLBCAM
[NUM_TLBCAMS
];
77 } tlbcam_addrs
[NUM_TLBCAMS
];
79 extern unsigned int tlbcam_index
;
81 unsigned long tlbcam_sz(int idx
)
83 return tlbcam_addrs
[idx
].limit
- tlbcam_addrs
[idx
].start
+ 1;
87 * Return PA for this VA if it is mapped by a CAM, or 0
89 phys_addr_t
v_mapped_by_tlbcam(unsigned long va
)
92 for (b
= 0; b
< tlbcam_index
; ++b
)
93 if (va
>= tlbcam_addrs
[b
].start
&& va
< tlbcam_addrs
[b
].limit
)
94 return tlbcam_addrs
[b
].phys
+ (va
- tlbcam_addrs
[b
].start
);
99 * Return VA for a given PA or 0 if not mapped
101 unsigned long p_mapped_by_tlbcam(phys_addr_t pa
)
104 for (b
= 0; b
< tlbcam_index
; ++b
)
105 if (pa
>= tlbcam_addrs
[b
].phys
106 && pa
< (tlbcam_addrs
[b
].limit
-tlbcam_addrs
[b
].start
)
107 +tlbcam_addrs
[b
].phys
)
108 return tlbcam_addrs
[b
].start
+(pa
-tlbcam_addrs
[b
].phys
);
112 void loadcam_entry(int idx
)
114 mtspr(SPRN_MAS0
, TLBCAM
[idx
].MAS0
);
115 mtspr(SPRN_MAS1
, TLBCAM
[idx
].MAS1
);
116 mtspr(SPRN_MAS2
, TLBCAM
[idx
].MAS2
);
117 mtspr(SPRN_MAS3
, TLBCAM
[idx
].MAS3
);
119 if (cur_cpu_spec
->cpu_features
& MMU_FTR_BIG_PHYS
)
120 mtspr(SPRN_MAS7
, TLBCAM
[idx
].MAS7
);
122 asm volatile("isync;tlbwe;isync" : : : "memory");
126 * Set up one of the I/D BAT (block address translation) register pairs.
127 * The parameters are not checked; in particular size must be a power
128 * of 4 between 4k and 256M.
130 static void settlbcam(int index
, unsigned long virt
, phys_addr_t phys
,
131 unsigned long size
, unsigned long flags
, unsigned int pid
)
133 unsigned int tsize
, lz
;
135 asm (PPC_CNTLZL
"%0,%1" : "=r" (lz
) : "r" (size
));
139 if ((flags
& _PAGE_NO_CACHE
) == 0)
140 flags
|= _PAGE_COHERENT
;
143 TLBCAM
[index
].MAS0
= MAS0_TLBSEL(1) | MAS0_ESEL(index
) | MAS0_NV(index
+1);
144 TLBCAM
[index
].MAS1
= MAS1_VALID
| MAS1_IPROT
| MAS1_TSIZE(tsize
) | MAS1_TID(pid
);
145 TLBCAM
[index
].MAS2
= virt
& PAGE_MASK
;
147 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_WRITETHRU
) ? MAS2_W
: 0;
148 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_NO_CACHE
) ? MAS2_I
: 0;
149 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_COHERENT
) ? MAS2_M
: 0;
150 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_GUARDED
) ? MAS2_G
: 0;
151 TLBCAM
[index
].MAS2
|= (flags
& _PAGE_ENDIAN
) ? MAS2_E
: 0;
153 TLBCAM
[index
].MAS3
= (phys
& MAS3_RPN
) | MAS3_SX
| MAS3_SR
;
154 TLBCAM
[index
].MAS3
|= ((flags
& _PAGE_RW
) ? MAS3_SW
: 0);
155 if (cur_cpu_spec
->cpu_features
& MMU_FTR_BIG_PHYS
)
156 TLBCAM
[index
].MAS7
= (u64
)phys
>> 32;
158 #ifndef CONFIG_KGDB /* want user access for breakpoints */
159 if (flags
& _PAGE_USER
) {
160 TLBCAM
[index
].MAS3
|= MAS3_UX
| MAS3_UR
;
161 TLBCAM
[index
].MAS3
|= ((flags
& _PAGE_RW
) ? MAS3_UW
: 0);
164 TLBCAM
[index
].MAS3
|= MAS3_UX
| MAS3_UR
;
165 TLBCAM
[index
].MAS3
|= ((flags
& _PAGE_RW
) ? MAS3_UW
: 0);
168 tlbcam_addrs
[index
].start
= virt
;
169 tlbcam_addrs
[index
].limit
= virt
+ size
- 1;
170 tlbcam_addrs
[index
].phys
= phys
;
172 loadcam_entry(index
);
175 unsigned long map_mem_in_cams(unsigned long ram
, int max_cam_idx
)
178 unsigned long virt
= PAGE_OFFSET
;
179 phys_addr_t phys
= memstart_addr
;
180 unsigned long amount_mapped
= 0;
181 unsigned long max_cam
= (mfspr(SPRN_TLB1CFG
) >> 16) & 0xf;
183 /* Convert (4^max) kB to (2^max) bytes */
184 max_cam
= max_cam
* 2 + 10;
186 /* Calculate CAM values */
187 for (i
= 0; ram
&& i
< max_cam_idx
; i
++) {
188 unsigned int camsize
= __ilog2(ram
) & ~1U;
189 unsigned int align
= __ffs(virt
| phys
) & ~1U;
190 unsigned long cam_sz
;
194 if (camsize
> max_cam
)
197 cam_sz
= 1UL << camsize
;
198 settlbcam(i
, virt
, phys
, cam_sz
, PAGE_KERNEL_X
, 0);
201 amount_mapped
+= cam_sz
;
207 return amount_mapped
;
210 unsigned long __init
mmu_mapin_ram(unsigned long top
)
212 return tlbcam_addrs
[tlbcam_index
- 1].limit
- PAGE_OFFSET
+ 1;
216 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
218 void __init
MMU_init_hw(void)
220 flush_instruction_cache();
223 void __init
adjust_total_lowmem(void)
228 /* adjust lowmem size to __max_low_memory */
229 ram
= min((phys_addr_t
)__max_low_memory
, (phys_addr_t
)total_lowmem
);
231 __max_low_memory
= map_mem_in_cams(ram
, CONFIG_LOWMEM_CAM_NUM
);
233 pr_info("Memory CAM mapping: ");
234 for (i
= 0; i
< tlbcam_index
- 1; i
++)
235 pr_cont("%lu/", tlbcam_sz(i
) >> 20);
236 pr_cont("%lu Mb, residual: %dMb\n", tlbcam_sz(tlbcam_index
- 1) >> 20,
237 (unsigned int)((total_lowmem
- __max_low_memory
) >> 20));
239 __initial_memory_limit_addr
= memstart_addr
+ __max_low_memory
;