xref: /openbmc/linux/arch/sh/mm/cache-sh3.c (revision 2572f00d)
1 /*
2  * arch/sh/mm/cache-sh3.c
3  *
4  * Copyright (C) 1999, 2000  Niibe Yutaka
5  * Copyright (C) 2002 Paul Mundt
6  *
7  * Released under the terms of the GNU GPL v2.0.
8  */
9 
10 #include <linux/init.h>
11 #include <linux/mman.h>
12 #include <linux/mm.h>
13 #include <linux/threads.h>
14 #include <asm/addrspace.h>
15 #include <asm/page.h>
16 #include <asm/pgtable.h>
17 #include <asm/processor.h>
18 #include <asm/cache.h>
19 #include <asm/io.h>
20 #include <asm/uaccess.h>
21 #include <asm/pgalloc.h>
22 #include <asm/mmu_context.h>
23 #include <asm/cacheflush.h>
24 
25 /*
26  * Write back the dirty D-caches, but not invalidate them.
27  *
28  * Is this really worth it, or should we just alias this routine
29  * to __flush_purge_region too?
30  *
31  * START: Virtual Address (U0, P1, or P3)
32  * SIZE: Size of the region.
33  */
34 
35 static void sh3__flush_wback_region(void *start, int size)
36 {
37 	unsigned long v, j;
38 	unsigned long begin, end;
39 	unsigned long flags;
40 
41 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
42 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
43 		& ~(L1_CACHE_BYTES-1);
44 
45 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
46 		unsigned long addrstart = CACHE_OC_ADDRESS_ARRAY;
47 		for (j = 0; j < current_cpu_data.dcache.ways; j++) {
48 			unsigned long data, addr, p;
49 
50 			p = __pa(v);
51 			addr = addrstart | (v & current_cpu_data.dcache.entry_mask);
52 			local_irq_save(flags);
53 			data = __raw_readl(addr);
54 
55 			if ((data & CACHE_PHYSADDR_MASK) ==
56 			    (p & CACHE_PHYSADDR_MASK)) {
57 				data &= ~SH_CACHE_UPDATED;
58 				__raw_writel(data, addr);
59 				local_irq_restore(flags);
60 				break;
61 			}
62 			local_irq_restore(flags);
63 			addrstart += current_cpu_data.dcache.way_incr;
64 		}
65 	}
66 }
67 
68 /*
69  * Write back the dirty D-caches and invalidate them.
70  *
71  * START: Virtual Address (U0, P1, or P3)
72  * SIZE: Size of the region.
73  */
74 static void sh3__flush_purge_region(void *start, int size)
75 {
76 	unsigned long v;
77 	unsigned long begin, end;
78 
79 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
80 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
81 		& ~(L1_CACHE_BYTES-1);
82 
83 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
84 		unsigned long data, addr;
85 
86 		data = (v & 0xfffffc00); /* _Virtual_ address, ~U, ~V */
87 		addr = CACHE_OC_ADDRESS_ARRAY |
88 			(v & current_cpu_data.dcache.entry_mask) | SH_CACHE_ASSOC;
89 		__raw_writel(data, addr);
90 	}
91 }
92 
93 void __init sh3_cache_init(void)
94 {
95 	__flush_wback_region = sh3__flush_wback_region;
96 	__flush_purge_region = sh3__flush_purge_region;
97 
98 	/*
99 	 * No write back please
100 	 *
101 	 * Except I don't think there's any way to avoid the writeback.
102 	 * So we just alias it to sh3__flush_purge_region(). dwmw2.
103 	 */
104 	__flush_invalidate_region = sh3__flush_purge_region;
105 }
106