xref: /openbmc/linux/arch/sh/mm/cache-sh3.c (revision 55fd7e02)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * arch/sh/mm/cache-sh3.c
4  *
5  * Copyright (C) 1999, 2000  Niibe Yutaka
6  * Copyright (C) 2002 Paul Mundt
7  */
8 
9 #include <linux/init.h>
10 #include <linux/mman.h>
11 #include <linux/mm.h>
12 #include <linux/threads.h>
13 #include <asm/addrspace.h>
14 #include <asm/page.h>
15 #include <asm/processor.h>
16 #include <asm/cache.h>
17 #include <asm/io.h>
18 #include <linux/uaccess.h>
19 #include <asm/pgalloc.h>
20 #include <asm/mmu_context.h>
21 #include <asm/cacheflush.h>
22 
23 /*
24  * Write back the dirty D-caches, but not invalidate them.
25  *
26  * Is this really worth it, or should we just alias this routine
27  * to __flush_purge_region too?
28  *
29  * START: Virtual Address (U0, P1, or P3)
30  * SIZE: Size of the region.
31  */
32 
33 static void sh3__flush_wback_region(void *start, int size)
34 {
35 	unsigned long v, j;
36 	unsigned long begin, end;
37 	unsigned long flags;
38 
39 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
40 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
41 		& ~(L1_CACHE_BYTES-1);
42 
43 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
44 		unsigned long addrstart = CACHE_OC_ADDRESS_ARRAY;
45 		for (j = 0; j < current_cpu_data.dcache.ways; j++) {
46 			unsigned long data, addr, p;
47 
48 			p = __pa(v);
49 			addr = addrstart | (v & current_cpu_data.dcache.entry_mask);
50 			local_irq_save(flags);
51 			data = __raw_readl(addr);
52 
53 			if ((data & CACHE_PHYSADDR_MASK) ==
54 			    (p & CACHE_PHYSADDR_MASK)) {
55 				data &= ~SH_CACHE_UPDATED;
56 				__raw_writel(data, addr);
57 				local_irq_restore(flags);
58 				break;
59 			}
60 			local_irq_restore(flags);
61 			addrstart += current_cpu_data.dcache.way_incr;
62 		}
63 	}
64 }
65 
66 /*
67  * Write back the dirty D-caches and invalidate them.
68  *
69  * START: Virtual Address (U0, P1, or P3)
70  * SIZE: Size of the region.
71  */
72 static void sh3__flush_purge_region(void *start, int size)
73 {
74 	unsigned long v;
75 	unsigned long begin, end;
76 
77 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
78 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
79 		& ~(L1_CACHE_BYTES-1);
80 
81 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
82 		unsigned long data, addr;
83 
84 		data = (v & 0xfffffc00); /* _Virtual_ address, ~U, ~V */
85 		addr = CACHE_OC_ADDRESS_ARRAY |
86 			(v & current_cpu_data.dcache.entry_mask) | SH_CACHE_ASSOC;
87 		__raw_writel(data, addr);
88 	}
89 }
90 
91 void __init sh3_cache_init(void)
92 {
93 	__flush_wback_region = sh3__flush_wback_region;
94 	__flush_purge_region = sh3__flush_purge_region;
95 
96 	/*
97 	 * No write back please
98 	 *
99 	 * Except I don't think there's any way to avoid the writeback.
100 	 * So we just alias it to sh3__flush_purge_region(). dwmw2.
101 	 */
102 	__flush_invalidate_region = sh3__flush_purge_region;
103 }
104