Linux 2.6.28-rc5
[cris-mirror.git] / arch / powerpc / sysdev / fsl_lbc.c
blob0494ee55920f7c55f6aac6c2447a0cd7c2ad76c0
1 /*
2 * Freescale LBC and UPM routines.
4 * Copyright (c) 2007-2008 MontaVista Software, Inc.
6 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
14 #include <linux/init.h>
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/compiler.h>
18 #include <linux/spinlock.h>
19 #include <linux/types.h>
20 #include <linux/io.h>
21 #include <linux/of.h>
22 #include <asm/prom.h>
23 #include <asm/fsl_lbc.h>
25 static spinlock_t fsl_lbc_lock = __SPIN_LOCK_UNLOCKED(fsl_lbc_lock);
26 static struct fsl_lbc_regs __iomem *fsl_lbc_regs;
28 static char __initdata *compat_lbc[] = {
29 "fsl,pq2-localbus",
30 "fsl,pq2pro-localbus",
31 "fsl,pq3-localbus",
32 "fsl,elbc",
35 static int __init fsl_lbc_init(void)
37 struct device_node *lbus;
38 int i;
40 for (i = 0; i < ARRAY_SIZE(compat_lbc); i++) {
41 lbus = of_find_compatible_node(NULL, NULL, compat_lbc[i]);
42 if (lbus)
43 goto found;
45 return -ENODEV;
47 found:
48 fsl_lbc_regs = of_iomap(lbus, 0);
49 of_node_put(lbus);
50 if (!fsl_lbc_regs)
51 return -ENOMEM;
52 return 0;
54 arch_initcall(fsl_lbc_init);
56 /**
57 * fsl_lbc_find - find Localbus bank
58 * @addr_base: base address of the memory bank
60 * This function walks LBC banks comparing "Base address" field of the BR
61 * registers with the supplied addr_base argument. When bases match this
62 * function returns bank number (starting with 0), otherwise it returns
63 * appropriate errno value.
65 int fsl_lbc_find(phys_addr_t addr_base)
67 int i;
69 if (!fsl_lbc_regs)
70 return -ENODEV;
72 for (i = 0; i < ARRAY_SIZE(fsl_lbc_regs->bank); i++) {
73 __be32 br = in_be32(&fsl_lbc_regs->bank[i].br);
74 __be32 or = in_be32(&fsl_lbc_regs->bank[i].or);
76 if (br & BR_V && (br & or & BR_BA) == addr_base)
77 return i;
80 return -ENOENT;
82 EXPORT_SYMBOL(fsl_lbc_find);
84 /**
85 * fsl_upm_find - find pre-programmed UPM via base address
86 * @addr_base: base address of the memory bank controlled by the UPM
87 * @upm: pointer to the allocated fsl_upm structure
89 * This function fills fsl_upm structure so you can use it with the rest of
90 * UPM API. On success this function returns 0, otherwise it returns
91 * appropriate errno value.
93 int fsl_upm_find(phys_addr_t addr_base, struct fsl_upm *upm)
95 int bank;
96 __be32 br;
98 bank = fsl_lbc_find(addr_base);
99 if (bank < 0)
100 return bank;
102 br = in_be32(&fsl_lbc_regs->bank[bank].br);
104 switch (br & BR_MSEL) {
105 case BR_MS_UPMA:
106 upm->mxmr = &fsl_lbc_regs->mamr;
107 break;
108 case BR_MS_UPMB:
109 upm->mxmr = &fsl_lbc_regs->mbmr;
110 break;
111 case BR_MS_UPMC:
112 upm->mxmr = &fsl_lbc_regs->mcmr;
113 break;
114 default:
115 return -EINVAL;
118 switch (br & BR_PS) {
119 case BR_PS_8:
120 upm->width = 8;
121 break;
122 case BR_PS_16:
123 upm->width = 16;
124 break;
125 case BR_PS_32:
126 upm->width = 32;
127 break;
128 default:
129 return -EINVAL;
132 return 0;
134 EXPORT_SYMBOL(fsl_upm_find);
137 * fsl_upm_run_pattern - actually run an UPM pattern
138 * @upm: pointer to the fsl_upm structure obtained via fsl_upm_find
139 * @io_base: remapped pointer to where memory access should happen
140 * @mar: MAR register content during pattern execution
142 * This function triggers dummy write to the memory specified by the io_base,
143 * thus UPM pattern actually executed. Note that mar usage depends on the
144 * pre-programmed AMX bits in the UPM RAM.
146 int fsl_upm_run_pattern(struct fsl_upm *upm, void __iomem *io_base, u32 mar)
148 int ret = 0;
149 unsigned long flags;
151 spin_lock_irqsave(&fsl_lbc_lock, flags);
153 out_be32(&fsl_lbc_regs->mar, mar << (32 - upm->width));
155 switch (upm->width) {
156 case 8:
157 out_8(io_base, 0x0);
158 break;
159 case 16:
160 out_be16(io_base, 0x0);
161 break;
162 case 32:
163 out_be32(io_base, 0x0);
164 break;
165 default:
166 ret = -EINVAL;
167 break;
170 spin_unlock_irqrestore(&fsl_lbc_lock, flags);
172 return ret;
174 EXPORT_SYMBOL(fsl_upm_run_pattern);