fbdev: Garbage collect fbdev scrolling acceleration, part 1 (from TODO list)
[linux-2.6-microblaze.git] / arch / m68k / mm / cache.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/arch/m68k/mm/cache.c
4  *
5  *  Instruction cache handling
6  *
7  *  Copyright (C) 1995  Hamish Macdonald
8  */
9
10 #include <linux/module.h>
11 #include <asm/cacheflush.h>
12 #include <asm/traps.h>
13
14
15 static unsigned long virt_to_phys_slow(unsigned long vaddr)
16 {
17         if (CPU_IS_060) {
18                 unsigned long paddr;
19
20                 /* The PLPAR instruction causes an access error if the translation
21                  * is not possible. To catch this we use the same exception mechanism
22                  * as for user space accesses in <asm/uaccess.h>. */
23                 asm volatile (".chip 68060\n"
24                               "1: plpar (%0)\n"
25                               ".chip 68k\n"
26                               "2:\n"
27                               ".section .fixup,\"ax\"\n"
28                               "   .even\n"
29                               "3: sub.l %0,%0\n"
30                               "   jra 2b\n"
31                               ".previous\n"
32                               ".section __ex_table,\"a\"\n"
33                               "   .align 4\n"
34                               "   .long 1b,3b\n"
35                               ".previous"
36                               : "=a" (paddr)
37                               : "0" (vaddr));
38                 return paddr;
39         } else if (CPU_IS_040) {
40                 unsigned long mmusr;
41
42                 asm volatile (".chip 68040\n\t"
43                               "ptestr (%1)\n\t"
44                               "movec %%mmusr, %0\n\t"
45                               ".chip 68k"
46                               : "=r" (mmusr)
47                               : "a" (vaddr));
48
49                 if (mmusr & MMU_R_040)
50                         return (mmusr & PAGE_MASK) | (vaddr & ~PAGE_MASK);
51         } else {
52                 unsigned short mmusr;
53                 unsigned long *descaddr;
54
55                 asm volatile ("ptestr %3,%2@,#7,%0\n\t"
56                               "pmove %%psr,%1"
57                               : "=a&" (descaddr), "=m" (mmusr)
58                               : "a" (vaddr), "d" (get_fs().seg));
59                 if (mmusr & (MMU_I|MMU_B|MMU_L))
60                         return 0;
61                 descaddr = phys_to_virt((unsigned long)descaddr);
62                 switch (mmusr & MMU_NUM) {
63                 case 1:
64                         return (*descaddr & 0xfe000000) | (vaddr & 0x01ffffff);
65                 case 2:
66                         return (*descaddr & 0xfffc0000) | (vaddr & 0x0003ffff);
67                 case 3:
68                         return (*descaddr & PAGE_MASK) | (vaddr & ~PAGE_MASK);
69                 }
70         }
71         return 0;
72 }
73
74 /* Push n pages at kernel virtual address and clear the icache */
75 /* RZ: use cpush %bc instead of cpush %dc, cinv %ic */
76 void flush_icache_user_range(unsigned long address, unsigned long endaddr)
77 {
78         if (CPU_IS_COLDFIRE) {
79                 unsigned long start, end;
80                 start = address & ICACHE_SET_MASK;
81                 end = endaddr & ICACHE_SET_MASK;
82                 if (start > end) {
83                         flush_cf_icache(0, end);
84                         end = ICACHE_MAX_ADDR;
85                 }
86                 flush_cf_icache(start, end);
87         } else if (CPU_IS_040_OR_060) {
88                 address &= PAGE_MASK;
89
90                 do {
91                         asm volatile ("nop\n\t"
92                                       ".chip 68040\n\t"
93                                       "cpushp %%bc,(%0)\n\t"
94                                       ".chip 68k"
95                                       : : "a" (virt_to_phys_slow(address)));
96                         address += PAGE_SIZE;
97                 } while (address < endaddr);
98         } else {
99                 unsigned long tmp;
100                 asm volatile ("movec %%cacr,%0\n\t"
101                               "orw %1,%0\n\t"
102                               "movec %0,%%cacr"
103                               : "=&d" (tmp)
104                               : "di" (FLUSH_I));
105         }
106 }
107
108 void flush_icache_range(unsigned long address, unsigned long endaddr)
109 {
110         mm_segment_t old_fs = get_fs();
111
112         set_fs(KERNEL_DS);
113         flush_icache_user_range(address, endaddr);
114         set_fs(old_fs);
115 }
116 EXPORT_SYMBOL(flush_icache_range);
117
118 void flush_icache_user_page(struct vm_area_struct *vma, struct page *page,
119                              unsigned long addr, int len)
120 {
121         if (CPU_IS_COLDFIRE) {
122                 unsigned long start, end;
123                 start = addr & ICACHE_SET_MASK;
124                 end = (addr + len) & ICACHE_SET_MASK;
125                 if (start > end) {
126                         flush_cf_icache(0, end);
127                         end = ICACHE_MAX_ADDR;
128                 }
129                 flush_cf_icache(start, end);
130
131         } else if (CPU_IS_040_OR_060) {
132                 asm volatile ("nop\n\t"
133                               ".chip 68040\n\t"
134                               "cpushp %%bc,(%0)\n\t"
135                               ".chip 68k"
136                               : : "a" (page_to_phys(page)));
137         } else {
138                 unsigned long tmp;
139                 asm volatile ("movec %%cacr,%0\n\t"
140                               "orw %1,%0\n\t"
141                               "movec %0,%%cacr"
142                               : "=&d" (tmp)
143                               : "di" (FLUSH_I));
144         }
145 }
146