MIPS: Yosemite, Emma: Fix off-by-two in arcs_cmdline buffer size check
[linux-2.6/linux-mips.git] / arch / mips / mm / sc-ip22.c
bloba6bd11fba7bf773f507130b3e90f57fe39b62904
1 /*
2 * sc-ip22.c: Indy cache management functions.
4 * Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org),
5 * derived from r4xx0.c by David S. Miller (davem@davemloft.net).
6 */
7 #include <linux/init.h>
8 #include <linux/kernel.h>
9 #include <linux/sched.h>
10 #include <linux/mm.h>
12 #include <asm/bcache.h>
13 #include <asm/page.h>
14 #include <asm/pgtable.h>
15 #include <asm/system.h>
16 #include <asm/bootinfo.h>
17 #include <asm/sgi/ip22.h>
18 #include <asm/sgi/mc.h>
20 /* Secondary cache size in bytes, if present. */
21 static unsigned long scache_size;
23 #undef DEBUG_CACHE
25 #define SC_SIZE 0x00080000
26 #define SC_LINE 32
27 #define CI_MASK (SC_SIZE - SC_LINE)
28 #define SC_INDEX(n) ((n) & CI_MASK)
30 static inline void indy_sc_wipe(unsigned long first, unsigned long last)
32 unsigned long tmp;
34 __asm__ __volatile__(
35 ".set\tpush\t\t\t# indy_sc_wipe\n\t"
36 ".set\tnoreorder\n\t"
37 ".set\tmips3\n\t"
38 ".set\tnoat\n\t"
39 "mfc0\t%2, $12\n\t"
40 "li\t$1, 0x80\t\t\t# Go 64 bit\n\t"
41 "mtc0\t$1, $12\n\t"
43 "dli\t$1, 0x9000000080000000\n\t"
44 "or\t%0, $1\t\t\t# first line to flush\n\t"
45 "or\t%1, $1\t\t\t# last line to flush\n\t"
46 ".set\tat\n\t"
48 "1:\tsw\t$0, 0(%0)\n\t"
49 "bne\t%0, %1, 1b\n\t"
50 " daddu\t%0, 32\n\t"
52 "mtc0\t%2, $12\t\t\t# Back to 32 bit\n\t"
53 "nop; nop; nop; nop;\n\t"
54 ".set\tpop"
55 : "=r" (first), "=r" (last), "=&r" (tmp)
56 : "0" (first), "1" (last));
59 static void indy_sc_wback_invalidate(unsigned long addr, unsigned long size)
61 unsigned long first_line, last_line;
62 unsigned long flags;
64 #ifdef DEBUG_CACHE
65 printk("indy_sc_wback_invalidate[%08lx,%08lx]", addr, size);
66 #endif
68 /* Catch bad driver code */
69 BUG_ON(size == 0);
71 /* Which lines to flush? */
72 first_line = SC_INDEX(addr);
73 last_line = SC_INDEX(addr + size - 1);
75 local_irq_save(flags);
76 if (first_line <= last_line) {
77 indy_sc_wipe(first_line, last_line);
78 goto out;
81 indy_sc_wipe(first_line, SC_SIZE - SC_LINE);
82 indy_sc_wipe(0, last_line);
83 out:
84 local_irq_restore(flags);
87 static void indy_sc_enable(void)
89 unsigned long addr, tmp1, tmp2;
91 /* This is really cool... */
92 #ifdef DEBUG_CACHE
93 printk("Enabling R4600 SCACHE\n");
94 #endif
95 __asm__ __volatile__(
96 ".set\tpush\n\t"
97 ".set\tnoreorder\n\t"
98 ".set\tmips3\n\t"
99 "mfc0\t%2, $12\n\t"
100 "nop; nop; nop; nop;\n\t"
101 "li\t%1, 0x80\n\t"
102 "mtc0\t%1, $12\n\t"
103 "nop; nop; nop; nop;\n\t"
104 "li\t%0, 0x1\n\t"
105 "dsll\t%0, 31\n\t"
106 "lui\t%1, 0x9000\n\t"
107 "dsll32\t%1, 0\n\t"
108 "or\t%0, %1, %0\n\t"
109 "sb\t$0, 0(%0)\n\t"
110 "mtc0\t$0, $12\n\t"
111 "nop; nop; nop; nop;\n\t"
112 "mtc0\t%2, $12\n\t"
113 "nop; nop; nop; nop;\n\t"
114 ".set\tpop"
115 : "=r" (tmp1), "=r" (tmp2), "=r" (addr));
118 static void indy_sc_disable(void)
120 unsigned long tmp1, tmp2, tmp3;
122 #ifdef DEBUG_CACHE
123 printk("Disabling R4600 SCACHE\n");
124 #endif
125 __asm__ __volatile__(
126 ".set\tpush\n\t"
127 ".set\tnoreorder\n\t"
128 ".set\tmips3\n\t"
129 "li\t%0, 0x1\n\t"
130 "dsll\t%0, 31\n\t"
131 "lui\t%1, 0x9000\n\t"
132 "dsll32\t%1, 0\n\t"
133 "or\t%0, %1, %0\n\t"
134 "mfc0\t%2, $12\n\t"
135 "nop; nop; nop; nop\n\t"
136 "li\t%1, 0x80\n\t"
137 "mtc0\t%1, $12\n\t"
138 "nop; nop; nop; nop\n\t"
139 "sh\t$0, 0(%0)\n\t"
140 "mtc0\t$0, $12\n\t"
141 "nop; nop; nop; nop\n\t"
142 "mtc0\t%2, $12\n\t"
143 "nop; nop; nop; nop\n\t"
144 ".set\tpop"
145 : "=r" (tmp1), "=r" (tmp2), "=r" (tmp3));
148 static inline int __init indy_sc_probe(void)
150 unsigned int size = ip22_eeprom_read(&sgimc->eeprom, 17);
151 if (size == 0)
152 return 0;
154 size <<= PAGE_SHIFT;
155 printk(KERN_INFO "R4600/R5000 SCACHE size %dK, linesize 32 bytes.\n",
156 size >> 10);
157 scache_size = size;
159 return 1;
162 /* XXX Check with wje if the Indy caches can differenciate between
163 writeback + invalidate and just invalidate. */
164 static struct bcache_ops indy_sc_ops = {
165 .bc_enable = indy_sc_enable,
166 .bc_disable = indy_sc_disable,
167 .bc_wback_inv = indy_sc_wback_invalidate,
168 .bc_inv = indy_sc_wback_invalidate
171 void __cpuinit indy_sc_init(void)
173 if (indy_sc_probe()) {
174 indy_sc_enable();
175 bcops = &indy_sc_ops;