xref: /openbmc/linux/arch/m68k/mm/cache.c (revision 132db935)
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/pgalloc.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 
147