1 /*
2  *  linux/include/asm-arm/arch-clps711x/mmu.h
3  *
4  *  Copyright (C) 1999 ARM Limited
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 #ifndef __ASM_ARCH_MMU_H
21 #define __ASM_ARCH_MMU_H
22 
23 #include <linux/config.h>
24 
25 /*
26  * Task size: 3GB
27  */
28 #define TASK_SIZE	(0xc0000000UL)
29 #define TASK_SIZE_26	(0x04000000UL)
30 
31 /*
32  * This decides where the kernel will search for a free chunk of vm
33  * space during mmap's.
34  */
35 #define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
36 
37 /*
38  * Page offset: 3GB
39  */
40 #define PAGE_OFFSET	(0xc0000000UL)
41 #define PHYS_OFFSET	(0x10000000UL)
42 
43 /*
44  * On integrator, the dram is contiguous
45  */
46 #define __virt_to_phys__is_a_macro
47 #define __virt_to_phys(vpage) ((vpage) - PAGE_OFFSET + PHYS_OFFSET)
48 #define __phys_to_virt__is_a_macro
49 #define __phys_to_virt(ppage) ((ppage) + PAGE_OFFSET - PHYS_OFFSET)
50 
51 /*
52  * Virtual view <-> DMA view memory address translations
53  * virt_to_bus: Used to translate the virtual address to an
54  *              address suitable to be passed to set_dma_addr
55  * bus_to_virt: Used to convert an address for DMA operations
56  *              to an address that the kernel can use.
57  */
58 
59 #define __virt_to_bus__is_a_macro
60 #define __virt_to_bus(x)	((x) - PAGE_OFFSET)
61 #define __bus_to_virt__is_a_macro
62 #define __bus_to_virt(x)	((x) + PAGE_OFFSET)
63 
64 
65 /*
66  * Like the SA1100, the EDB7211 has a large gap between physical RAM
67  * banks.  In 2.2, the Psion (CL-PS7110) port added custom support for
68  * discontiguous physical memory.  In 2.4, we can use the standard
69  * Linux NUMA support.
70  *
71  * This is not necessary for EP7211 implementations with only one used
72  * memory bank.  For those systems, simply undefine CONFIG_DISCONTIGMEM.
73  */
74 
75 #ifdef CONFIG_DISCONTIGMEM
76 /*
77  * Because of the wide memory address space between physical RAM banks on the
78  * SA1100, it's much more convenient to use Linux's NUMA support to implement
79  * our memory map representation.  Assuming all memory nodes have equal access
80  * characteristics, we then have generic discontigous memory support.
81  *
82  * Of course, all this isn't mandatory for SA1100 implementations with only
83  * one used memory bank.  For those, simply undefine CONFIG_DISCONTIGMEM.
84  *
85  * The nodes are matched with the physical memory bank addresses which are
86  * incidentally the same as virtual addresses.
87  *
88  * 	node 0:  0xc0000000 - 0xc7ffffff
89  * 	node 1:  0xc8000000 - 0xcfffffff
90  * 	node 2:  0xd0000000 - 0xd7ffffff
91  * 	node 3:  0xd8000000 - 0xdfffffff
92  */
93 
94 #define NR_NODES	4
95 
96 /*
97  * Given a kernel address, find the home node of the underlying memory.
98  */
99 #define KVADDR_TO_NID(addr) \
100 		(((unsigned long)(addr) - PAGE_OFFSET) >> NODE_MAX_MEM_SHIFT)
101 
102 /*
103  * Given a page frame number, convert it to a node id.
104  */
105 #define PFN_TO_NID(pfn) \
106 	(((pfn) - PHYS_PFN_OFFSET) >> (NODE_MAX_MEM_SHIFT - PAGE_SHIFT))
107 
108 /*
109  * Given a kaddr, ADDR_TO_MAPBASE finds the owning node of the memory
110  * and returns the mem_map of that node.
111  */
112 #define ADDR_TO_MAPBASE(kaddr) \
113 			NODE_MEM_MAP(KVADDR_TO_NID((unsigned long)(kaddr)))
114 
115 #define PFN_TO_MAPBASE(pfn)	NODE_MEM_MAP(PFN_TO_NID(pfn))
116 
117 /*
118  * Given a kaddr, LOCAL_MAR_NR finds the owning node of the memory
119  * and returns the index corresponding to the appropriate page in the
120  * node's mem_map.
121  */
122 #define LOCAL_MAP_NR(addr) \
123 	(((unsigned long)(addr) & (NODE_MAX_MEM_SIZE - 1)) >> PAGE_SHIFT)
124 
125 /*
126  * The 7500 has up-to 64Mb of memory per bank
127  */
128 #define NODE_MAX_MEM_SHIFT	26
129 #define NODE_MAX_MEM_SIZE	(1<<NODE_MAX_MEM_SHIFT)
130 
131 #endif /* CONFIG_DISCONTIGMEM */
132 
133 #endif
134