xref: /openbmc/linux/arch/m68k/mm/cache.c (revision 0a94608f)
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 		WARN_ON_ONCE(!CPU_IS_040_OR_060);
53 	}
54 	return 0;
55 }
56 
57 /* Push n pages at kernel virtual address and clear the icache */
58 /* RZ: use cpush %bc instead of cpush %dc, cinv %ic */
59 void flush_icache_user_range(unsigned long address, unsigned long endaddr)
60 {
61 	if (CPU_IS_COLDFIRE) {
62 		unsigned long start, end;
63 		start = address & ICACHE_SET_MASK;
64 		end = endaddr & ICACHE_SET_MASK;
65 		if (start > end) {
66 			flush_cf_icache(0, end);
67 			end = ICACHE_MAX_ADDR;
68 		}
69 		flush_cf_icache(start, end);
70 	} else if (CPU_IS_040_OR_060) {
71 		address &= PAGE_MASK;
72 
73 		do {
74 			asm volatile ("nop\n\t"
75 				      ".chip 68040\n\t"
76 				      "cpushp %%bc,(%0)\n\t"
77 				      ".chip 68k"
78 				      : : "a" (virt_to_phys_slow(address)));
79 			address += PAGE_SIZE;
80 		} while (address < endaddr);
81 	} else {
82 		unsigned long tmp;
83 		asm volatile ("movec %%cacr,%0\n\t"
84 			      "orw %1,%0\n\t"
85 			      "movec %0,%%cacr"
86 			      : "=&d" (tmp)
87 			      : "di" (FLUSH_I));
88 	}
89 }
90 
91 void flush_icache_range(unsigned long address, unsigned long endaddr)
92 {
93 	set_fc(SUPER_DATA);
94 	flush_icache_user_range(address, endaddr);
95 	set_fc(USER_DATA);
96 }
97 EXPORT_SYMBOL(flush_icache_range);
98 
99 void flush_icache_user_page(struct vm_area_struct *vma, struct page *page,
100 			     unsigned long addr, int len)
101 {
102 	if (CPU_IS_COLDFIRE) {
103 		unsigned long start, end;
104 		start = addr & ICACHE_SET_MASK;
105 		end = (addr + len) & ICACHE_SET_MASK;
106 		if (start > end) {
107 			flush_cf_icache(0, end);
108 			end = ICACHE_MAX_ADDR;
109 		}
110 		flush_cf_icache(start, end);
111 
112 	} else if (CPU_IS_040_OR_060) {
113 		asm volatile ("nop\n\t"
114 			      ".chip 68040\n\t"
115 			      "cpushp %%bc,(%0)\n\t"
116 			      ".chip 68k"
117 			      : : "a" (page_to_phys(page)));
118 	} else {
119 		unsigned long tmp;
120 		asm volatile ("movec %%cacr,%0\n\t"
121 			      "orw %1,%0\n\t"
122 			      "movec %0,%%cacr"
123 			      : "=&d" (tmp)
124 			      : "di" (FLUSH_I));
125 	}
126 }
127 
128