xref: /openbmc/linux/arch/sh/mm/cache-sh2.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * arch/sh/mm/cache-sh2.c
3  *
4  * Copyright (C) 2002 Paul Mundt
5  *
6  * Released under the terms of the GNU GPL v2.0.
7  */
8 #include <linux/init.h>
9 #include <linux/mm.h>
10 
11 #include <asm/cache.h>
12 #include <asm/addrspace.h>
13 #include <asm/processor.h>
14 #include <asm/cacheflush.h>
15 #include <asm/io.h>
16 
17 /*
18  * Calculate the OC address and set the way bit on the SH-2.
19  *
20  * We must have already jump_to_P2()'ed prior to calling this
21  * function, since we rely on CCR manipulation to do the
22  * Right Thing(tm).
23  */
24 unsigned long __get_oc_addr(unsigned long set, unsigned long way)
25 {
26 	unsigned long ccr;
27 
28 	/*
29 	 * On SH-2 the way bit isn't tracked in the address field
30 	 * if we're doing address array access .. instead, we need
31 	 * to manually switch out the way in the CCR.
32 	 */
33 	ccr = ctrl_inl(CCR);
34 	ccr &= ~0x00c0;
35 	ccr |= way << cpu_data->dcache.way_shift;
36 
37 	/*
38 	 * Despite the number of sets being halved, we end up losing
39 	 * the first 2 ways to OCRAM instead of the last 2 (if we're
40 	 * 4-way). As a result, forcibly setting the W1 bit handily
41 	 * bumps us up 2 ways.
42 	 */
43 	if (ccr & CCR_CACHE_ORA)
44 		ccr |= 1 << (cpu_data->dcache.way_shift + 1);
45 
46 	ctrl_outl(ccr, CCR);
47 
48 	return CACHE_OC_ADDRESS_ARRAY | (set << cpu_data->dcache.entry_shift);
49 }
50 
51