Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
[linux-2.6.git] / arch / cris / arch-v32 / mm / init.c
1 /*
2  * Set up paging and the MMU.
3  *
4  * Copyright (C) 2000-2003, Axis Communications AB.
5  *
6  * Authors:   Bjorn Wesen <bjornw@axis.com>
7  *            Tobias Anderberg <tobiasa@axis.com>, CRISv32 port.
8  */
9 #include <linux/mmzone.h>
10 #include <linux/init.h>
11 #include <linux/bootmem.h>
12 #include <linux/mm.h>
13 #include <asm/pgtable.h>
14 #include <asm/page.h>
15 #include <asm/types.h>
16 #include <asm/mmu.h>
17 #include <asm/io.h>
18 #include <asm/mmu_context.h>
19 #include <asm/arch/hwregs/asm/mmu_defs_asm.h>
20 #include <asm/arch/hwregs/supp_reg.h>
21
22 extern void tlb_init(void);
23
24 /*
25  * The kernel is already mapped with linear mapping at kseg_c so there's no
26  * need to map it with a page table. However, head.S also temporarily mapped it
27  * at kseg_4 thus the ksegs are set up again. Also clear the TLB and do various
28  * other paging stuff.
29  */
30 void __init
31 cris_mmu_init(void)
32 {
33         unsigned long mmu_config;
34         unsigned long mmu_kbase_hi;
35         unsigned long mmu_kbase_lo;
36         unsigned short mmu_page_id;
37
38         /*
39          * Make sure the current pgd table points to something sane, even if it
40          * is most probably not used until the next switch_mm.
41          */
42         per_cpu(current_pgd, smp_processor_id()) = init_mm.pgd;
43
44 #ifdef CONFIG_SMP
45         {
46                 pgd_t **pgd;
47                 pgd = (pgd_t**)&per_cpu(current_pgd, smp_processor_id());
48                 SUPP_BANK_SEL(1);
49                 SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
50                 SUPP_BANK_SEL(2);
51                 SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
52         }
53 #endif
54
55         /* Initialise the TLB. Function found in tlb.c. */
56         tlb_init();
57
58         /* Enable exceptions and initialize the kernel segments. */
59         mmu_config = ( REG_STATE(mmu, rw_mm_cfg, we, on)        |
60                        REG_STATE(mmu, rw_mm_cfg, acc, on)       |
61                        REG_STATE(mmu, rw_mm_cfg, ex, on)        |
62                        REG_STATE(mmu, rw_mm_cfg, inv, on)       |
63                        REG_STATE(mmu, rw_mm_cfg, seg_f, linear) |
64                        REG_STATE(mmu, rw_mm_cfg, seg_e, linear) |
65                        REG_STATE(mmu, rw_mm_cfg, seg_d, page)   |
66                        REG_STATE(mmu, rw_mm_cfg, seg_c, linear) |
67                        REG_STATE(mmu, rw_mm_cfg, seg_b, linear) |
68 #ifndef CONFIG_ETRAXFS_SIM
69                        REG_STATE(mmu, rw_mm_cfg, seg_a, page)   |
70 #else
71                        REG_STATE(mmu, rw_mm_cfg, seg_a, linear) |
72 #endif
73                        REG_STATE(mmu, rw_mm_cfg, seg_9, page)   |
74                        REG_STATE(mmu, rw_mm_cfg, seg_8, page)   |
75                        REG_STATE(mmu, rw_mm_cfg, seg_7, page)   |
76                        REG_STATE(mmu, rw_mm_cfg, seg_6, page)   |
77                        REG_STATE(mmu, rw_mm_cfg, seg_5, page)   |
78                        REG_STATE(mmu, rw_mm_cfg, seg_4, page)   |
79                        REG_STATE(mmu, rw_mm_cfg, seg_3, page)   |
80                        REG_STATE(mmu, rw_mm_cfg, seg_2, page)   |
81                        REG_STATE(mmu, rw_mm_cfg, seg_1, page)   |
82                        REG_STATE(mmu, rw_mm_cfg, seg_0, page));
83
84         mmu_kbase_hi = ( REG_FIELD(mmu, rw_mm_kbase_hi, base_f, 0x0) |
85                          REG_FIELD(mmu, rw_mm_kbase_hi, base_e, 0x8) |
86                          REG_FIELD(mmu, rw_mm_kbase_hi, base_d, 0x0) |
87 #ifndef CONFIG_ETRAXFS_SIM
88                          REG_FIELD(mmu, rw_mm_kbase_hi, base_c, 0x4) |
89 #else
90                          REG_FIELD(mmu, rw_mm_kbase_hi, base_c, 0x0) |
91 #endif
92                          REG_FIELD(mmu, rw_mm_kbase_hi, base_b, 0xb) |
93 #ifndef CONFIG_ETRAXFS_SIM
94                          REG_FIELD(mmu, rw_mm_kbase_hi, base_a, 0x0) |
95 #else
96                          REG_FIELD(mmu, rw_mm_kbase_hi, base_a, 0xa) |
97 #endif
98                          REG_FIELD(mmu, rw_mm_kbase_hi, base_9, 0x0) |
99                          REG_FIELD(mmu, rw_mm_kbase_hi, base_8, 0x0));
100
101         mmu_kbase_lo = ( REG_FIELD(mmu, rw_mm_kbase_lo, base_7, 0x0) |
102                          REG_FIELD(mmu, rw_mm_kbase_lo, base_6, 0x0) |
103                          REG_FIELD(mmu, rw_mm_kbase_lo, base_5, 0x0) |
104                          REG_FIELD(mmu, rw_mm_kbase_lo, base_4, 0x0) |
105                          REG_FIELD(mmu, rw_mm_kbase_lo, base_3, 0x0) |
106                          REG_FIELD(mmu, rw_mm_kbase_lo, base_2, 0x0) |
107                          REG_FIELD(mmu, rw_mm_kbase_lo, base_1, 0x0) |
108                          REG_FIELD(mmu, rw_mm_kbase_lo, base_0, 0x0));
109
110         mmu_page_id = REG_FIELD(mmu, rw_mm_tlb_hi, pid, 0);
111
112         /* Update the instruction MMU. */
113         SUPP_BANK_SEL(BANK_IM);
114         SUPP_REG_WR(RW_MM_CFG, mmu_config);
115         SUPP_REG_WR(RW_MM_KBASE_HI, mmu_kbase_hi);
116         SUPP_REG_WR(RW_MM_KBASE_LO, mmu_kbase_lo);
117         SUPP_REG_WR(RW_MM_TLB_HI, mmu_page_id);
118
119         /* Update the data MMU. */
120         SUPP_BANK_SEL(BANK_DM);
121         SUPP_REG_WR(RW_MM_CFG, mmu_config);
122         SUPP_REG_WR(RW_MM_KBASE_HI, mmu_kbase_hi);
123         SUPP_REG_WR(RW_MM_KBASE_LO, mmu_kbase_lo);
124         SUPP_REG_WR(RW_MM_TLB_HI, mmu_page_id);
125
126         SPEC_REG_WR(SPEC_REG_PID, 0);
127
128         /*
129          * The MMU has been enabled ever since head.S but just to make it
130          * totally obvious enable it here as well.
131          */
132         SUPP_BANK_SEL(BANK_GC);
133         SUPP_REG_WR(RW_GC_CFG, 0xf); /* IMMU, DMMU, ICache, DCache on */
134 }
135
136 void __init
137 paging_init(void)
138 {
139         int i;
140         unsigned long zones_size[MAX_NR_ZONES];
141
142         printk("Setting up paging and the MMU.\n");
143
144         /* Clear out the init_mm.pgd that will contain the kernel's mappings. */
145         for(i = 0; i < PTRS_PER_PGD; i++)
146                 swapper_pg_dir[i] = __pgd(0);
147
148         cris_mmu_init();
149
150         /*
151          * Initialize the bad page table and bad page to point to a couple of
152          * allocated pages.
153          */
154         empty_zero_page = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
155         memset((void *) empty_zero_page, 0, PAGE_SIZE);
156
157         /* All pages are DMA'able in Etrax, so put all in the DMA'able zone. */
158         zones_size[0] = ((unsigned long) high_memory - PAGE_OFFSET) >> PAGE_SHIFT;
159
160         for (i = 1; i < MAX_NR_ZONES; i++)
161                 zones_size[i] = 0;
162
163         /*
164          * Use free_area_init_node instead of free_area_init, because it is
165          * designed for systems where the DRAM starts at an address
166          * substantially higher than 0, like us (we start at PAGE_OFFSET). This
167          * saves space in the mem_map page array.
168          */
169         free_area_init_node(0, &contig_page_data, zones_size, PAGE_OFFSET >> PAGE_SHIFT, 0);
170
171         mem_map = contig_page_data.node_mem_map;
172 }