xref: /openbmc/linux/drivers/pcmcia/sa11xx_base.c (revision 384740dc)
1 /*======================================================================
2 
3     Device driver for the PCMCIA control functionality of StrongARM
4     SA-1100 microprocessors.
5 
6     The contents of this file are subject to the Mozilla Public
7     License Version 1.1 (the "License"); you may not use this file
8     except in compliance with the License. You may obtain a copy of
9     the License at http://www.mozilla.org/MPL/
10 
11     Software distributed under the License is distributed on an "AS
12     IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
13     implied. See the License for the specific language governing
14     rights and limitations under the License.
15 
16     The initial developer of the original code is John G. Dorsey
17     <john+@cs.cmu.edu>.  Portions created by John G. Dorsey are
18     Copyright (C) 1999 John G. Dorsey.  All Rights Reserved.
19 
20     Alternatively, the contents of this file may be used under the
21     terms of the GNU Public License version 2 (the "GPL"), in which
22     case the provisions of the GPL are applicable instead of the
23     above.  If you wish to allow the use of your version of this file
24     only under the terms of the GPL and not to allow others to use
25     your version of this file under the MPL, indicate your decision
26     by deleting the provisions above and replace them with the notice
27     and other provisions required by the GPL.  If you do not delete
28     the provisions above, a recipient may use your version of this
29     file under either the MPL or the GPL.
30 
31 ======================================================================*/
32 
33 #include <linux/module.h>
34 #include <linux/init.h>
35 #include <linux/cpufreq.h>
36 #include <linux/ioport.h>
37 #include <linux/kernel.h>
38 #include <linux/spinlock.h>
39 
40 #include <mach/hardware.h>
41 #include <asm/io.h>
42 #include <asm/irq.h>
43 #include <asm/system.h>
44 
45 #include "soc_common.h"
46 #include "sa11xx_base.h"
47 
48 
49 /*
50  * sa1100_pcmcia_default_mecr_timing
51  * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
52  *
53  * Calculate MECR clock wait states for given CPU clock
54  * speed and command wait state. This function can be over-
55  * written by a board specific version.
56  *
57  * The default is to simply calculate the BS values as specified in
58  * the INTEL SA1100 development manual
59  * "Expansion Memory (PCMCIA) Configuration Register (MECR)"
60  * that's section 10.2.5 in _my_ version of the manual ;)
61  */
62 static unsigned int
63 sa1100_pcmcia_default_mecr_timing(struct soc_pcmcia_socket *skt,
64 				  unsigned int cpu_speed,
65 				  unsigned int cmd_time)
66 {
67 	return sa1100_pcmcia_mecr_bs(cmd_time, cpu_speed);
68 }
69 
70 /* sa1100_pcmcia_set_mecr()
71  * ^^^^^^^^^^^^^^^^^^^^^^^^
72  *
73  * set MECR value for socket <sock> based on this sockets
74  * io, mem and attribute space access speed.
75  * Call board specific BS value calculation to allow boards
76  * to tweak the BS values.
77  */
78 static int
79 sa1100_pcmcia_set_mecr(struct soc_pcmcia_socket *skt, unsigned int cpu_clock)
80 {
81 	struct soc_pcmcia_timing timing;
82 	u32 mecr, old_mecr;
83 	unsigned long flags;
84 	unsigned int bs_io, bs_mem, bs_attr;
85 
86 	soc_common_pcmcia_get_timing(skt, &timing);
87 
88 	bs_io = skt->ops->get_timing(skt, cpu_clock, timing.io);
89 	bs_mem = skt->ops->get_timing(skt, cpu_clock, timing.mem);
90 	bs_attr = skt->ops->get_timing(skt, cpu_clock, timing.attr);
91 
92 	local_irq_save(flags);
93 
94 	old_mecr = mecr = MECR;
95 	MECR_FAST_SET(mecr, skt->nr, 0);
96 	MECR_BSIO_SET(mecr, skt->nr, bs_io);
97 	MECR_BSA_SET(mecr, skt->nr, bs_attr);
98 	MECR_BSM_SET(mecr, skt->nr, bs_mem);
99 	if (old_mecr != mecr)
100 		MECR = mecr;
101 
102 	local_irq_restore(flags);
103 
104 	debug(skt, 2, "FAST %X  BSM %X  BSA %X  BSIO %X\n",
105 	      MECR_FAST_GET(mecr, skt->nr),
106 	      MECR_BSM_GET(mecr, skt->nr), MECR_BSA_GET(mecr, skt->nr),
107 	      MECR_BSIO_GET(mecr, skt->nr));
108 
109 	return 0;
110 }
111 
112 #ifdef CONFIG_CPU_FREQ
113 static int
114 sa1100_pcmcia_frequency_change(struct soc_pcmcia_socket *skt,
115 			       unsigned long val,
116 			       struct cpufreq_freqs *freqs)
117 {
118 	switch (val) {
119 	case CPUFREQ_PRECHANGE:
120 		if (freqs->new > freqs->old)
121 			sa1100_pcmcia_set_mecr(skt, freqs->new);
122 		break;
123 
124 	case CPUFREQ_POSTCHANGE:
125 		if (freqs->new < freqs->old)
126 			sa1100_pcmcia_set_mecr(skt, freqs->new);
127 		break;
128 	case CPUFREQ_RESUMECHANGE:
129 		sa1100_pcmcia_set_mecr(skt, freqs->new);
130 		break;
131 	}
132 
133 	return 0;
134 }
135 
136 #endif
137 
138 static int
139 sa1100_pcmcia_set_timing(struct soc_pcmcia_socket *skt)
140 {
141 	return sa1100_pcmcia_set_mecr(skt, cpufreq_get(0));
142 }
143 
144 static int
145 sa1100_pcmcia_show_timing(struct soc_pcmcia_socket *skt, char *buf)
146 {
147 	struct soc_pcmcia_timing timing;
148 	unsigned int clock = cpufreq_get(0);
149 	unsigned long mecr = MECR;
150 	char *p = buf;
151 
152 	soc_common_pcmcia_get_timing(skt, &timing);
153 
154 	p+=sprintf(p, "I/O      : %u (%u)\n", timing.io,
155 		   sa1100_pcmcia_cmd_time(clock, MECR_BSIO_GET(mecr, skt->nr)));
156 
157 	p+=sprintf(p, "attribute: %u (%u)\n", timing.attr,
158 		   sa1100_pcmcia_cmd_time(clock, MECR_BSA_GET(mecr, skt->nr)));
159 
160 	p+=sprintf(p, "common   : %u (%u)\n", timing.mem,
161 		   sa1100_pcmcia_cmd_time(clock, MECR_BSM_GET(mecr, skt->nr)));
162 
163 	return p - buf;
164 }
165 
166 int sa11xx_drv_pcmcia_probe(struct device *dev, struct pcmcia_low_level *ops,
167 			    int first, int nr)
168 {
169 	/*
170 	 * set default MECR calculation if the board specific
171 	 * code did not specify one...
172 	 */
173 	if (!ops->get_timing)
174 		ops->get_timing = sa1100_pcmcia_default_mecr_timing;
175 
176 	/* Provide our SA11x0 specific timing routines. */
177 	ops->set_timing  = sa1100_pcmcia_set_timing;
178 	ops->show_timing = sa1100_pcmcia_show_timing;
179 #ifdef CONFIG_CPU_FREQ
180 	ops->frequency_change = sa1100_pcmcia_frequency_change;
181 #endif
182 
183 	return soc_common_drv_pcmcia_probe(dev, ops, first, nr);
184 }
185 EXPORT_SYMBOL(sa11xx_drv_pcmcia_probe);
186 
187 static int __init sa11xx_pcmcia_init(void)
188 {
189 	return 0;
190 }
191 fs_initcall(sa11xx_pcmcia_init);
192 
193 static void __exit sa11xx_pcmcia_exit(void) {}
194 
195 module_exit(sa11xx_pcmcia_exit);
196 
197 MODULE_AUTHOR("John Dorsey <john+@cs.cmu.edu>");
198 MODULE_DESCRIPTION("Linux PCMCIA Card Services: SA-11xx core socket driver");
199 MODULE_LICENSE("Dual MPL/GPL");
200