xref: /openbmc/linux/arch/m68k/mm/cache.c (revision 588b48ca)
1 /*
2  *  linux/arch/m68k/mm/cache.c
3  *
4  *  Instruction cache handling
5  *
6  *  Copyright (C) 1995  Hamish Macdonald
7  */
8 
9 #include <linux/module.h>
10 #include <asm/pgalloc.h>
11 #include <asm/traps.h>
12 
13 
14 static unsigned long virt_to_phys_slow(unsigned long vaddr)
15 {
16 	if (CPU_IS_060) {
17 		unsigned long paddr;
18 
19 		/* The PLPAR instruction causes an access error if the translation
20 		 * is not possible. To catch this we use the same exception mechanism
21 		 * as for user space accesses in <asm/uaccess.h>. */
22 		asm volatile (".chip 68060\n"
23 			      "1: plpar (%0)\n"
24 			      ".chip 68k\n"
25 			      "2:\n"
26 			      ".section .fixup,\"ax\"\n"
27 			      "   .even\n"
28 			      "3: sub.l %0,%0\n"
29 			      "   jra 2b\n"
30 			      ".previous\n"
31 			      ".section __ex_table,\"a\"\n"
32 			      "   .align 4\n"
33 			      "   .long 1b,3b\n"
34 			      ".previous"
35 			      : "=a" (paddr)
36 			      : "0" (vaddr));
37 		return paddr;
38 	} else if (CPU_IS_040) {
39 		unsigned long mmusr;
40 
41 		asm volatile (".chip 68040\n\t"
42 			      "ptestr (%1)\n\t"
43 			      "movec %%mmusr, %0\n\t"
44 			      ".chip 68k"
45 			      : "=r" (mmusr)
46 			      : "a" (vaddr));
47 
48 		if (mmusr & MMU_R_040)
49 			return (mmusr & PAGE_MASK) | (vaddr & ~PAGE_MASK);
50 	} else {
51 		unsigned short mmusr;
52 		unsigned long *descaddr;
53 
54 		asm volatile ("ptestr %3,%2@,#7,%0\n\t"
55 			      "pmove %%psr,%1"
56 			      : "=a&" (descaddr), "=m" (mmusr)
57 			      : "a" (vaddr), "d" (get_fs().seg));
58 		if (mmusr & (MMU_I|MMU_B|MMU_L))
59 			return 0;
60 		descaddr = phys_to_virt((unsigned long)descaddr);
61 		switch (mmusr & MMU_NUM) {
62 		case 1:
63 			return (*descaddr & 0xfe000000) | (vaddr & 0x01ffffff);
64 		case 2:
65 			return (*descaddr & 0xfffc0000) | (vaddr & 0x0003ffff);
66 		case 3:
67 			return (*descaddr & PAGE_MASK) | (vaddr & ~PAGE_MASK);
68 		}
69 	}
70 	return 0;
71 }
72 
73 /* Push n pages at kernel virtual address and clear the icache */
74 /* RZ: use cpush %bc instead of cpush %dc, cinv %ic */
75 void flush_icache_range(unsigned long address, unsigned long endaddr)
76 {
77 	if (CPU_IS_COLDFIRE) {
78 		unsigned long start, end;
79 		start = address & ICACHE_SET_MASK;
80 		end = endaddr & ICACHE_SET_MASK;
81 		if (start > end) {
82 			flush_cf_icache(0, end);
83 			end = ICACHE_MAX_ADDR;
84 		}
85 		flush_cf_icache(start, end);
86 	} else if (CPU_IS_040_OR_060) {
87 		address &= PAGE_MASK;
88 
89 		do {
90 			asm volatile ("nop\n\t"
91 				      ".chip 68040\n\t"
92 				      "cpushp %%bc,(%0)\n\t"
93 				      ".chip 68k"
94 				      : : "a" (virt_to_phys_slow(address)));
95 			address += PAGE_SIZE;
96 		} while (address < endaddr);
97 	} else {
98 		unsigned long tmp;
99 		asm volatile ("movec %%cacr,%0\n\t"
100 			      "orw %1,%0\n\t"
101 			      "movec %0,%%cacr"
102 			      : "=&d" (tmp)
103 			      : "di" (FLUSH_I));
104 	}
105 }
106 EXPORT_SYMBOL(flush_icache_range);
107 
108 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
109 			     unsigned long addr, int len)
110 {
111 	if (CPU_IS_COLDFIRE) {
112 		unsigned long start, end;
113 		start = addr & ICACHE_SET_MASK;
114 		end = (addr + len) & ICACHE_SET_MASK;
115 		if (start > end) {
116 			flush_cf_icache(0, end);
117 			end = ICACHE_MAX_ADDR;
118 		}
119 		flush_cf_icache(start, end);
120 
121 	} else if (CPU_IS_040_OR_060) {
122 		asm volatile ("nop\n\t"
123 			      ".chip 68040\n\t"
124 			      "cpushp %%bc,(%0)\n\t"
125 			      ".chip 68k"
126 			      : : "a" (page_to_phys(page)));
127 	} else {
128 		unsigned long tmp;
129 		asm volatile ("movec %%cacr,%0\n\t"
130 			      "orw %1,%0\n\t"
131 			      "movec %0,%%cacr"
132 			      : "=&d" (tmp)
133 			      : "di" (FLUSH_I));
134 	}
135 }
136 
137