xref: /openbmc/linux/arch/arm/mm/cache-l2x0.c (revision 0eb948dd)
1 /*
2  * arch/arm/mm/cache-l2x0.c - L210/L220 cache controller support
3  *
4  * Copyright (C) 2007 ARM Limited
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18  */
19 #include <linux/init.h>
20 #include <linux/spinlock.h>
21 #include <linux/io.h>
22 
23 #include <asm/cacheflush.h>
24 #include <asm/hardware/cache-l2x0.h>
25 
26 #define CACHE_LINE_SIZE		32
27 
28 static void __iomem *l2x0_base;
29 static DEFINE_SPINLOCK(l2x0_lock);
30 
31 static inline void sync_writel(unsigned long val, unsigned long reg,
32 			       unsigned long complete_mask)
33 {
34 	writel(val, l2x0_base + reg);
35 	/* wait for the operation to complete */
36 	while (readl(l2x0_base + reg) & complete_mask)
37 		;
38 }
39 
40 static inline void cache_sync(void)
41 {
42 	sync_writel(0, L2X0_CACHE_SYNC, 1);
43 }
44 
45 static inline void l2x0_inv_all(void)
46 {
47 	unsigned long flags;
48 
49 	/* invalidate all ways */
50 	spin_lock_irqsave(&l2x0_lock, flags);
51 	sync_writel(0xff, L2X0_INV_WAY, 0xff);
52 	cache_sync();
53 	spin_unlock_irqrestore(&l2x0_lock, flags);
54 }
55 
56 static void l2x0_inv_range(unsigned long start, unsigned long end)
57 {
58 	unsigned long flags;
59 
60 	spin_lock_irqsave(&l2x0_lock, flags);
61 	if (start & (CACHE_LINE_SIZE - 1)) {
62 		start &= ~(CACHE_LINE_SIZE - 1);
63 		sync_writel(start, L2X0_CLEAN_INV_LINE_PA, 1);
64 		start += CACHE_LINE_SIZE;
65 	}
66 
67 	if (end & (CACHE_LINE_SIZE - 1)) {
68 		end &= ~(CACHE_LINE_SIZE - 1);
69 		sync_writel(end, L2X0_CLEAN_INV_LINE_PA, 1);
70 	}
71 
72 	while (start < end) {
73 		unsigned long blk_end = start + min(end - start, 4096UL);
74 
75 		while (start < blk_end) {
76 			sync_writel(start, L2X0_INV_LINE_PA, 1);
77 			start += CACHE_LINE_SIZE;
78 		}
79 
80 		if (blk_end < end) {
81 			spin_unlock_irqrestore(&l2x0_lock, flags);
82 			spin_lock_irqsave(&l2x0_lock, flags);
83 		}
84 	}
85 	cache_sync();
86 	spin_unlock_irqrestore(&l2x0_lock, flags);
87 }
88 
89 static void l2x0_clean_range(unsigned long start, unsigned long end)
90 {
91 	unsigned long flags;
92 
93 	spin_lock_irqsave(&l2x0_lock, flags);
94 	start &= ~(CACHE_LINE_SIZE - 1);
95 	while (start < end) {
96 		unsigned long blk_end = start + min(end - start, 4096UL);
97 
98 		while (start < blk_end) {
99 			sync_writel(start, L2X0_CLEAN_LINE_PA, 1);
100 			start += CACHE_LINE_SIZE;
101 		}
102 
103 		if (blk_end < end) {
104 			spin_unlock_irqrestore(&l2x0_lock, flags);
105 			spin_lock_irqsave(&l2x0_lock, flags);
106 		}
107 	}
108 	cache_sync();
109 	spin_unlock_irqrestore(&l2x0_lock, flags);
110 }
111 
112 static void l2x0_flush_range(unsigned long start, unsigned long end)
113 {
114 	unsigned long flags;
115 
116 	spin_lock_irqsave(&l2x0_lock, flags);
117 	start &= ~(CACHE_LINE_SIZE - 1);
118 	while (start < end) {
119 		unsigned long blk_end = start + min(end - start, 4096UL);
120 
121 		while (start < blk_end) {
122 			sync_writel(start, L2X0_CLEAN_INV_LINE_PA, 1);
123 			start += CACHE_LINE_SIZE;
124 		}
125 
126 		if (blk_end < end) {
127 			spin_unlock_irqrestore(&l2x0_lock, flags);
128 			spin_lock_irqsave(&l2x0_lock, flags);
129 		}
130 	}
131 	cache_sync();
132 	spin_unlock_irqrestore(&l2x0_lock, flags);
133 }
134 
135 void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask)
136 {
137 	__u32 aux;
138 
139 	l2x0_base = base;
140 
141 	/* disable L2X0 */
142 	writel(0, l2x0_base + L2X0_CTRL);
143 
144 	aux = readl(l2x0_base + L2X0_AUX_CTRL);
145 	aux &= aux_mask;
146 	aux |= aux_val;
147 	writel(aux, l2x0_base + L2X0_AUX_CTRL);
148 
149 	l2x0_inv_all();
150 
151 	/* enable L2X0 */
152 	writel(1, l2x0_base + L2X0_CTRL);
153 
154 	outer_cache.inv_range = l2x0_inv_range;
155 	outer_cache.clean_range = l2x0_clean_range;
156 	outer_cache.flush_range = l2x0_flush_range;
157 
158 	printk(KERN_INFO "L2X0 cache controller enabled\n");
159 }
160