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	(0xc0000000UL)
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 #if defined(CONFIG_ARCH_CDB89712)
60 
61 #define __virt_to_bus__is_a_macro
62 #define __virt_to_bus(x)	(x)
63 #define __bus_to_virt__is_a_macro
64 #define __bus_to_virt(x)	(x)
65 
66 #elif defined (CONFIG_ARCH_AUTCPU12)
67 
68 #define __virt_to_bus__is_a_macro
69 #define __virt_to_bus(x)	(x)
70 #define __bus_to_virt__is_a_macro
71 #define __bus_to_virt(x)	(x)
72 
73 #else
74 
75 #define __virt_to_bus__is_a_macro
76 #define __virt_to_bus(x)	((x) - PAGE_OFFSET)
77 #define __bus_to_virt__is_a_macro
78 #define __bus_to_virt(x)	((x) + PAGE_OFFSET)
79 
80 #endif
81 
82 
83 /*
84  * Like the SA1100, the EDB7211 has a large gap between physical RAM
85  * banks.  In 2.2, the Psion (CL-PS7110) port added custom support for
86  * discontiguous physical memory.  In 2.4, we can use the standard
87  * Linux NUMA support.
88  *
89  * This is not necessary for EP7211 implementations with only one used
90  * memory bank.  For those systems, simply undefine CONFIG_DISCONTIGMEM.
91  */
92 
93 #ifdef CONFIG_DISCONTIGMEM
94 /*
95  * Because of the wide memory address space between physical RAM banks on the
96  * SA1100, it's much more convenient to use Linux's NUMA support to implement
97  * our memory map representation.  Assuming all memory nodes have equal access
98  * characteristics, we then have generic discontigous memory support.
99  *
100  * Of course, all this isn't mandatory for SA1100 implementations with only
101  * one used memory bank.  For those, simply undefine CONFIG_DISCONTIGMEM.
102  *
103  * The nodes are matched with the physical memory bank addresses which are
104  * incidentally the same as virtual addresses.
105  *
106  * 	node 0:  0xc0000000 - 0xc7ffffff
107  * 	node 1:  0xc8000000 - 0xcfffffff
108  * 	node 2:  0xd0000000 - 0xd7ffffff
109  * 	node 3:  0xd8000000 - 0xdfffffff
110  */
111 
112 #define NR_NODES	4
113 
114 /*
115  * Given a kernel address, find the home node of the underlying memory.
116  */
117 #define KVADDR_TO_NID(addr) \
118 		(((unsigned long)(addr) - PAGE_OFFSET) >> NODE_MAX_MEM_SHIFT)
119 
120 /*
121  * Given a page frame number, convert it to a node id.
122  */
123 #define PFN_TO_NID(pfn) \
124 	(((pfn) - PHYS_PFN_OFFSET) >> (NODE_MAX_MEM_SHIFT - PAGE_SHIFT))
125 
126 /*
127  * Given a kaddr, ADDR_TO_MAPBASE finds the owning node of the memory
128  * and returns the mem_map of that node.
129  */
130 #define ADDR_TO_MAPBASE(kaddr) \
131 			NODE_MEM_MAP(KVADDR_TO_NID((unsigned long)(kaddr)))
132 
133 #define PFN_TO_MAPBASE(pfn)	NODE_MEM_MAP(PFN_TO_NID(pfn))
134 
135 /*
136  * Given a kaddr, LOCAL_MAR_NR finds the owning node of the memory
137  * and returns the index corresponding to the appropriate page in the
138  * node's mem_map.
139  */
140 #define LOCAL_MAP_NR(addr) \
141 	(((unsigned long)(addr) & (NODE_MAX_MEM_SIZE - 1)) >> PAGE_SHIFT)
142 
143 /*
144  * The PS7211 allows up to 256MB max per DRAM bank, but the EDB7211
145  * uses only one of the two banks (bank #1).  However, even within
146  * bank #1, memory is discontiguous.
147  *
148  * The EDB7211 has two 8MB DRAM areas with 8MB of empty space between
149  * them, so we use 24 for the node max shift to get 16MB node sizes.
150  */
151 #define NODE_MAX_MEM_SHIFT	24
152 #define NODE_MAX_MEM_SIZE	(1<<NODE_MAX_MEM_SHIFT)
153 
154 #endif /* CONFIG_DISCONTIGMEM */
155 
156 #endif
157 
158