xref: /openbmc/linux/arch/arm/mm/cache-l2x0.c (revision b627b4ed)
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 	unsigned long flags;
35 
36 	spin_lock_irqsave(&l2x0_lock, flags);
37 	writel(val, l2x0_base + reg);
38 	/* wait for the operation to complete */
39 	while (readl(l2x0_base + reg) & complete_mask)
40 		;
41 	spin_unlock_irqrestore(&l2x0_lock, flags);
42 }
43 
44 static inline void cache_sync(void)
45 {
46 	sync_writel(0, L2X0_CACHE_SYNC, 1);
47 }
48 
49 static inline void l2x0_inv_all(void)
50 {
51 	/* invalidate all ways */
52 	sync_writel(0xff, L2X0_INV_WAY, 0xff);
53 	cache_sync();
54 }
55 
56 static void l2x0_inv_range(unsigned long start, unsigned long end)
57 {
58 	unsigned long addr;
59 
60 	if (start & (CACHE_LINE_SIZE - 1)) {
61 		start &= ~(CACHE_LINE_SIZE - 1);
62 		sync_writel(start, L2X0_CLEAN_INV_LINE_PA, 1);
63 		start += CACHE_LINE_SIZE;
64 	}
65 
66 	if (end & (CACHE_LINE_SIZE - 1)) {
67 		end &= ~(CACHE_LINE_SIZE - 1);
68 		sync_writel(end, L2X0_CLEAN_INV_LINE_PA, 1);
69 	}
70 
71 	for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
72 		sync_writel(addr, L2X0_INV_LINE_PA, 1);
73 	cache_sync();
74 }
75 
76 static void l2x0_clean_range(unsigned long start, unsigned long end)
77 {
78 	unsigned long addr;
79 
80 	start &= ~(CACHE_LINE_SIZE - 1);
81 	for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
82 		sync_writel(addr, L2X0_CLEAN_LINE_PA, 1);
83 	cache_sync();
84 }
85 
86 static void l2x0_flush_range(unsigned long start, unsigned long end)
87 {
88 	unsigned long addr;
89 
90 	start &= ~(CACHE_LINE_SIZE - 1);
91 	for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
92 		sync_writel(addr, L2X0_CLEAN_INV_LINE_PA, 1);
93 	cache_sync();
94 }
95 
96 void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask)
97 {
98 	__u32 aux;
99 
100 	l2x0_base = base;
101 
102 	/* disable L2X0 */
103 	writel(0, l2x0_base + L2X0_CTRL);
104 
105 	aux = readl(l2x0_base + L2X0_AUX_CTRL);
106 	aux &= aux_mask;
107 	aux |= aux_val;
108 	writel(aux, l2x0_base + L2X0_AUX_CTRL);
109 
110 	l2x0_inv_all();
111 
112 	/* enable L2X0 */
113 	writel(1, l2x0_base + L2X0_CTRL);
114 
115 	outer_cache.inv_range = l2x0_inv_range;
116 	outer_cache.clean_range = l2x0_clean_range;
117 	outer_cache.flush_range = l2x0_flush_range;
118 
119 	printk(KERN_INFO "L2X0 cache controller enabled\n");
120 }
121