xref: /openbmc/linux/arch/sh/mm/cache-sh3.c (revision 842ed298)
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/mmu_context.h>
20 #include <asm/cacheflush.h>
21 
22 /*
23  * Write back the dirty D-caches, but not invalidate them.
24  *
25  * Is this really worth it, or should we just alias this routine
26  * to __flush_purge_region too?
27  *
28  * START: Virtual Address (U0, P1, or P3)
29  * SIZE: Size of the region.
30  */
31 
32 static void sh3__flush_wback_region(void *start, int size)
33 {
34 	unsigned long v, j;
35 	unsigned long begin, end;
36 	unsigned long flags;
37 
38 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
39 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
40 		& ~(L1_CACHE_BYTES-1);
41 
42 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
43 		unsigned long addrstart = CACHE_OC_ADDRESS_ARRAY;
44 		for (j = 0; j < current_cpu_data.dcache.ways; j++) {
45 			unsigned long data, addr, p;
46 
47 			p = __pa(v);
48 			addr = addrstart | (v & current_cpu_data.dcache.entry_mask);
49 			local_irq_save(flags);
50 			data = __raw_readl(addr);
51 
52 			if ((data & CACHE_PHYSADDR_MASK) ==
53 			    (p & CACHE_PHYSADDR_MASK)) {
54 				data &= ~SH_CACHE_UPDATED;
55 				__raw_writel(data, addr);
56 				local_irq_restore(flags);
57 				break;
58 			}
59 			local_irq_restore(flags);
60 			addrstart += current_cpu_data.dcache.way_incr;
61 		}
62 	}
63 }
64 
65 /*
66  * Write back the dirty D-caches and invalidate them.
67  *
68  * START: Virtual Address (U0, P1, or P3)
69  * SIZE: Size of the region.
70  */
71 static void sh3__flush_purge_region(void *start, int size)
72 {
73 	unsigned long v;
74 	unsigned long begin, end;
75 
76 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
77 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
78 		& ~(L1_CACHE_BYTES-1);
79 
80 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
81 		unsigned long data, addr;
82 
83 		data = (v & 0xfffffc00); /* _Virtual_ address, ~U, ~V */
84 		addr = CACHE_OC_ADDRESS_ARRAY |
85 			(v & current_cpu_data.dcache.entry_mask) | SH_CACHE_ASSOC;
86 		__raw_writel(data, addr);
87 	}
88 }
89 
90 void __init sh3_cache_init(void)
91 {
92 	__flush_wback_region = sh3__flush_wback_region;
93 	__flush_purge_region = sh3__flush_purge_region;
94 
95 	/*
96 	 * No write back please
97 	 *
98 	 * Except I don't think there's any way to avoid the writeback.
99 	 * So we just alias it to sh3__flush_purge_region(). dwmw2.
100 	 */
101 	__flush_invalidate_region = sh3__flush_purge_region;
102 }
103