Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
cs.c
Go to the documentation of this file.
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License. See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2008 Maxime Bizon <[email protected]>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/spinlock.h>
12 #include <linux/log2.h>
13 #include <bcm63xx_cpu.h>
14 #include <bcm63xx_io.h>
15 #include <bcm63xx_regs.h>
16 #include <bcm63xx_cs.h>
17 
18 static DEFINE_SPINLOCK(bcm63xx_cs_lock);
19 
20 /*
21  * check if given chip select exists
22  */
23 static int is_valid_cs(unsigned int cs)
24 {
25  if (cs > 6)
26  return 0;
27  return 1;
28 }
29 
30 /*
31  * Configure chipselect base address and size (bytes).
32  * Size must be a power of two between 8k and 256M.
33  */
34 int bcm63xx_set_cs_base(unsigned int cs, u32 base, unsigned int size)
35 {
36  unsigned long flags;
37  u32 val;
38 
39  if (!is_valid_cs(cs))
40  return -EINVAL;
41 
42  /* sanity check on size */
43  if (size != roundup_pow_of_two(size))
44  return -EINVAL;
45 
46  if (size < 8 * 1024 || size > 256 * 1024 * 1024)
47  return -EINVAL;
48 
49  val = (base & MPI_CSBASE_BASE_MASK);
50  /* 8k => 0 - 256M => 15 */
51  val |= (ilog2(size) - ilog2(8 * 1024)) << MPI_CSBASE_SIZE_SHIFT;
52 
53  spin_lock_irqsave(&bcm63xx_cs_lock, flags);
54  bcm_mpi_writel(val, MPI_CSBASE_REG(cs));
55  spin_unlock_irqrestore(&bcm63xx_cs_lock, flags);
56 
57  return 0;
58 }
59 
60 EXPORT_SYMBOL(bcm63xx_set_cs_base);
61 
62 /*
63  * configure chipselect timing (ns)
64  */
65 int bcm63xx_set_cs_timing(unsigned int cs, unsigned int wait,
66  unsigned int setup, unsigned int hold)
67 {
68  unsigned long flags;
69  u32 val;
70 
71  if (!is_valid_cs(cs))
72  return -EINVAL;
73 
74  spin_lock_irqsave(&bcm63xx_cs_lock, flags);
75  val = bcm_mpi_readl(MPI_CSCTL_REG(cs));
76  val &= ~(MPI_CSCTL_WAIT_MASK);
77  val &= ~(MPI_CSCTL_SETUP_MASK);
78  val &= ~(MPI_CSCTL_HOLD_MASK);
79  val |= wait << MPI_CSCTL_WAIT_SHIFT;
80  val |= setup << MPI_CSCTL_SETUP_SHIFT;
81  val |= hold << MPI_CSCTL_HOLD_SHIFT;
82  bcm_mpi_writel(val, MPI_CSCTL_REG(cs));
83  spin_unlock_irqrestore(&bcm63xx_cs_lock, flags);
84 
85  return 0;
86 }
87 
88 EXPORT_SYMBOL(bcm63xx_set_cs_timing);
89 
90 /*
91  * configure other chipselect parameter (data bus size, ...)
92  */
93 int bcm63xx_set_cs_param(unsigned int cs, u32 params)
94 {
95  unsigned long flags;
96  u32 val;
97 
98  if (!is_valid_cs(cs))
99  return -EINVAL;
100 
101  /* none of this fields apply to pcmcia */
102  if (cs == MPI_CS_PCMCIA_COMMON ||
103  cs == MPI_CS_PCMCIA_ATTR ||
104  cs == MPI_CS_PCMCIA_IO)
105  return -EINVAL;
106 
107  spin_lock_irqsave(&bcm63xx_cs_lock, flags);
108  val = bcm_mpi_readl(MPI_CSCTL_REG(cs));
109  val &= ~(MPI_CSCTL_DATA16_MASK);
110  val &= ~(MPI_CSCTL_SYNCMODE_MASK);
111  val &= ~(MPI_CSCTL_TSIZE_MASK);
112  val &= ~(MPI_CSCTL_ENDIANSWAP_MASK);
113  val |= params;
114  bcm_mpi_writel(val, MPI_CSCTL_REG(cs));
115  spin_unlock_irqrestore(&bcm63xx_cs_lock, flags);
116 
117  return 0;
118 }
119 
120 EXPORT_SYMBOL(bcm63xx_set_cs_param);
121 
122 /*
123  * set cs status (enable/disable)
124  */
125 int bcm63xx_set_cs_status(unsigned int cs, int enable)
126 {
127  unsigned long flags;
128  u32 val;
129 
130  if (!is_valid_cs(cs))
131  return -EINVAL;
132 
133  spin_lock_irqsave(&bcm63xx_cs_lock, flags);
134  val = bcm_mpi_readl(MPI_CSCTL_REG(cs));
135  if (enable)
136  val |= MPI_CSCTL_ENABLE_MASK;
137  else
138  val &= ~MPI_CSCTL_ENABLE_MASK;
139  bcm_mpi_writel(val, MPI_CSCTL_REG(cs));
140  spin_unlock_irqrestore(&bcm63xx_cs_lock, flags);
141  return 0;
142 }
143 
144 EXPORT_SYMBOL(bcm63xx_set_cs_status);
Generated on Thu Jan 10 2013 13:08:58 for Linux Kernel by   doxygen 1.8.2