xref: /openbmc/linux/arch/sh/mm/cache-sh3.c (revision b08918fb)
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/pgtable.h>
16 #include <asm/processor.h>
17 #include <asm/cache.h>
18 #include <asm/io.h>
19 #include <linux/uaccess.h>
20 #include <asm/pgalloc.h>
21 #include <asm/mmu_context.h>
22 #include <asm/cacheflush.h>
23 
24 /*
25  * Write back the dirty D-caches, but not invalidate them.
26  *
27  * Is this really worth it, or should we just alias this routine
28  * to __flush_purge_region too?
29  *
30  * START: Virtual Address (U0, P1, or P3)
31  * SIZE: Size of the region.
32  */
33 
34 static void sh3__flush_wback_region(void *start, int size)
35 {
36 	unsigned long v, j;
37 	unsigned long begin, end;
38 	unsigned long flags;
39 
40 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
41 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
42 		& ~(L1_CACHE_BYTES-1);
43 
44 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
45 		unsigned long addrstart = CACHE_OC_ADDRESS_ARRAY;
46 		for (j = 0; j < current_cpu_data.dcache.ways; j++) {
47 			unsigned long data, addr, p;
48 
49 			p = __pa(v);
50 			addr = addrstart | (v & current_cpu_data.dcache.entry_mask);
51 			local_irq_save(flags);
52 			data = __raw_readl(addr);
53 
54 			if ((data & CACHE_PHYSADDR_MASK) ==
55 			    (p & CACHE_PHYSADDR_MASK)) {
56 				data &= ~SH_CACHE_UPDATED;
57 				__raw_writel(data, addr);
58 				local_irq_restore(flags);
59 				break;
60 			}
61 			local_irq_restore(flags);
62 			addrstart += current_cpu_data.dcache.way_incr;
63 		}
64 	}
65 }
66 
67 /*
68  * Write back the dirty D-caches and invalidate them.
69  *
70  * START: Virtual Address (U0, P1, or P3)
71  * SIZE: Size of the region.
72  */
73 static void sh3__flush_purge_region(void *start, int size)
74 {
75 	unsigned long v;
76 	unsigned long begin, end;
77 
78 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
79 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
80 		& ~(L1_CACHE_BYTES-1);
81 
82 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
83 		unsigned long data, addr;
84 
85 		data = (v & 0xfffffc00); /* _Virtual_ address, ~U, ~V */
86 		addr = CACHE_OC_ADDRESS_ARRAY |
87 			(v & current_cpu_data.dcache.entry_mask) | SH_CACHE_ASSOC;
88 		__raw_writel(data, addr);
89 	}
90 }
91 
92 void __init sh3_cache_init(void)
93 {
94 	__flush_wback_region = sh3__flush_wback_region;
95 	__flush_purge_region = sh3__flush_purge_region;
96 
97 	/*
98 	 * No write back please
99 	 *
100 	 * Except I don't think there's any way to avoid the writeback.
101 	 * So we just alias it to sh3__flush_purge_region(). dwmw2.
102 	 */
103 	__flush_invalidate_region = sh3__flush_purge_region;
104 }
105