aboutsummaryrefslogtreecommitdiff
path: root/arch/mips/mm/sc-ip22.c
blob: d7238687d7902c7f4025bd9f069e2c05f19c3fbd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
// SPDX-License-Identifier: GPL-2.0
/*
 * sc-ip22.c: Indy cache management functions.
 *
 * Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org),
 * derived from r4xx0.c by David S. Miller (davem@davemloft.net).
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>

#include <asm/bcache.h>
#include <asm/page.h>
#include <asm/bootinfo.h>
#include <asm/sgi/ip22.h>
#include <asm/sgi/mc.h>

/* Secondary cache size in bytes, if present.  */
static unsigned long scache_size;

#undef DEBUG_CACHE

#define SC_SIZE 0x00080000
#define SC_LINE 32
#define CI_MASK (SC_SIZE - SC_LINE)
#define SC_INDEX(n) ((n) & CI_MASK)

static inline void indy_sc_wipe(unsigned long first, unsigned long last)
{
	unsigned long tmp;

	__asm__ __volatile__(
	"	.set	push			# indy_sc_wipe		\n"
	"	.set	noreorder					\n"
	"	.set	mips3						\n"
	"	.set	noat						\n"
	"	mfc0	%2, $12						\n"
	"	li	$1, 0x80		# Go 64 bit		\n"
	"	mtc0	$1, $12						\n"
	"								\n"
	"	#							\n"
	"	# Open code a dli $1, 0x9000000080000000		\n"
	"	#							\n"
	"	# Required because binutils 2.25 will happily accept	\n"
	"	# 64 bit instructions in .set mips3 mode but puke on	\n"
	"	# 64 bit constants when generating 32 bit ELF		\n"
	"	#							\n"
	"	lui	$1,0x9000					\n"
	"	dsll	$1,$1,0x10					\n"
	"	ori	$1,$1,0x8000					\n"
	"	dsll	$1,$1,0x10					\n"
	"								\n"
	"	or	%0, $1			# first line to flush	\n"
	"	or	%1, $1			# last line to flush	\n"
	"	.set	at						\n"
	"								\n"
	"1:	sw	$0, 0(%0)					\n"
	"	bne	%0, %1, 1b					\n"
	"	 daddu	%0, 32						\n"
	"								\n"
	"	mtc0	%2, $12			# Back to 32 bit	\n"
	"	nop				# pipeline hazard	\n"
	"	nop							\n"
	"	nop							\n"
	"	nop							\n"
	"	.set	pop						\n"
	: "=r" (first), "=r" (last), "=&r" (tmp)
	: "0" (first), "1" (last));
}

static void indy_sc_wback_invalidate(unsigned long addr, unsigned long size)
{
	unsigned long first_line, last_line;
	unsigned long flags;

#ifdef DEBUG_CACHE
	printk("indy_sc_wback_invalidate[%08lx,%08lx]", addr, size);
#endif

	/* Catch bad driver code */
	BUG_ON(size == 0);

	/* Which lines to flush?  */
	first_line = SC_INDEX(addr);
	last_line = SC_INDEX(addr + size - 1);

	local_irq_save(flags);
	if (first_line <= last_line) {
		indy_sc_wipe(first_line, last_line);
		goto out;
	}

	indy_sc_wipe(first_line, SC_SIZE - SC_LINE);
	indy_sc_wipe(0, last_line);
out:
	local_irq_restore(flags);
}

static void indy_sc_enable(void)
{
	unsigned long addr, tmp1, tmp2;

	/* This is really cool... */
#ifdef DEBUG_CACHE
	printk("Enabling R4600 SCACHE\n");
#endif
	__asm__ __volatile__(
	".set\tpush\n\t"
	".set\tnoreorder\n\t"
	".set\tmips3\n\t"
	"mfc0\t%2, $12\n\t"
	"nop; nop; nop; nop;\n\t"
	"li\t%1, 0x80\n\t"
	"mtc0\t%1, $12\n\t"
	"nop; nop; nop; nop;\n\t"
	"li\t%0, 0x1\n\t"
	"dsll\t%0, 31\n\t"
	"lui\t%1, 0x9000\n\t"
	"dsll32\t%1, 0\n\t"
	"or\t%0, %1, %0\n\t"
	"sb\t$0, 0(%0)\n\t"
	"mtc0\t$0, $12\n\t"
	"nop; nop; nop; nop;\n\t"
	"mtc0\t%2, $12\n\t"
	"nop; nop; nop; nop;\n\t"
	".set\tpop"
	: "=r" (tmp1), "=r" (tmp2), "=r" (addr));
}

static void indy_sc_disable(void)
{
	unsigned long tmp1, tmp2, tmp3;

#ifdef DEBUG_CACHE
	printk("Disabling R4600 SCACHE\n");
#endif
	__asm__ __volatile__(
	".set\tpush\n\t"
	".set\tnoreorder\n\t"
	".set\tmips3\n\t"
	"li\t%0, 0x1\n\t"
	"dsll\t%0, 31\n\t"
	"lui\t%1, 0x9000\n\t"
	"dsll32\t%1, 0\n\t"
	"or\t%0, %1, %0\n\t"
	"mfc0\t%2, $12\n\t"
	"nop; nop; nop; nop\n\t"
	"li\t%1, 0x80\n\t"
	"mtc0\t%1, $12\n\t"
	"nop; nop; nop; nop\n\t"
	"sh\t$0, 0(%0)\n\t"
	"mtc0\t$0, $12\n\t"
	"nop; nop; nop; nop\n\t"
	"mtc0\t%2, $12\n\t"
	"nop; nop; nop; nop\n\t"
	".set\tpop"
	: "=r" (tmp1), "=r" (tmp2), "=r" (tmp3));
}

static inline int __init indy_sc_probe(void)
{
	unsigned int size = ip22_eeprom_read(&sgimc->eeprom, 17);
	if (size == 0)
		return 0;

	size <<= PAGE_SHIFT;
	printk(KERN_INFO "R4600/R5000 SCACHE size %dK, linesize 32 bytes.\n",
	       size >> 10);
	scache_size = size;

	return 1;
}

/* XXX Check with wje if the Indy caches can differentiate between
   writeback + invalidate and just invalidate.	*/
static struct bcache_ops indy_sc_ops = {
	.bc_enable = indy_sc_enable,
	.bc_disable = indy_sc_disable,
	.bc_wback_inv = indy_sc_wback_invalidate,
	.bc_inv = indy_sc_wback_invalidate
};

void indy_sc_init(void)
{
	if (indy_sc_probe()) {
		indy_sc_enable();
		bcops = &indy_sc_ops;
	}
}