xref: /openbmc/linux/drivers/pcmcia/sa11xx_base.c (revision 1da177e4)
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/config.h>
36 #include <linux/cpufreq.h>
37 #include <linux/ioport.h>
38 #include <linux/kernel.h>
39 #include <linux/spinlock.h>
40 
41 #include <asm/hardware.h>
42 #include <asm/io.h>
43 #include <asm/irq.h>
44 #include <asm/system.h>
45 
46 #include "soc_common.h"
47 #include "sa11xx_base.h"
48 
49 
50 /*
51  * sa1100_pcmcia_default_mecr_timing
52  * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
53  *
54  * Calculate MECR clock wait states for given CPU clock
55  * speed and command wait state. This function can be over-
56  * written by a board specific version.
57  *
58  * The default is to simply calculate the BS values as specified in
59  * the INTEL SA1100 development manual
60  * "Expansion Memory (PCMCIA) Configuration Register (MECR)"
61  * that's section 10.2.5 in _my_ version of the manual ;)
62  */
63 static unsigned int
64 sa1100_pcmcia_default_mecr_timing(struct soc_pcmcia_socket *skt,
65 				  unsigned int cpu_speed,
66 				  unsigned int cmd_time)
67 {
68 	return sa1100_pcmcia_mecr_bs(cmd_time, cpu_speed);
69 }
70 
71 /* sa1100_pcmcia_set_mecr()
72  * ^^^^^^^^^^^^^^^^^^^^^^^^
73  *
74  * set MECR value for socket <sock> based on this sockets
75  * io, mem and attribute space access speed.
76  * Call board specific BS value calculation to allow boards
77  * to tweak the BS values.
78  */
79 static int
80 sa1100_pcmcia_set_mecr(struct soc_pcmcia_socket *skt, unsigned int cpu_clock)
81 {
82 	struct soc_pcmcia_timing timing;
83 	u32 mecr, old_mecr;
84 	unsigned long flags;
85 	unsigned int bs_io, bs_mem, bs_attr;
86 
87 	soc_common_pcmcia_get_timing(skt, &timing);
88 
89 	bs_io = skt->ops->get_timing(skt, cpu_clock, timing.io);
90 	bs_mem = skt->ops->get_timing(skt, cpu_clock, timing.mem);
91 	bs_attr = skt->ops->get_timing(skt, cpu_clock, timing.attr);
92 
93 	local_irq_save(flags);
94 
95 	old_mecr = mecr = MECR;
96 	MECR_FAST_SET(mecr, skt->nr, 0);
97 	MECR_BSIO_SET(mecr, skt->nr, bs_io);
98 	MECR_BSA_SET(mecr, skt->nr, bs_attr);
99 	MECR_BSM_SET(mecr, skt->nr, bs_mem);
100 	if (old_mecr != mecr)
101 		MECR = mecr;
102 
103 	local_irq_restore(flags);
104 
105 	debug(skt, 2, "FAST %X  BSM %X  BSA %X  BSIO %X\n",
106 	      MECR_FAST_GET(mecr, skt->nr),
107 	      MECR_BSM_GET(mecr, skt->nr), MECR_BSA_GET(mecr, skt->nr),
108 	      MECR_BSIO_GET(mecr, skt->nr));
109 
110 	return 0;
111 }
112 
113 #ifdef CONFIG_CPU_FREQ
114 static int
115 sa1100_pcmcia_frequency_change(struct soc_pcmcia_socket *skt,
116 			       unsigned long val,
117 			       struct cpufreq_freqs *freqs)
118 {
119 	switch (val) {
120 	case CPUFREQ_PRECHANGE:
121 		if (freqs->new > freqs->old)
122 			sa1100_pcmcia_set_mecr(skt, freqs->new);
123 		break;
124 
125 	case CPUFREQ_POSTCHANGE:
126 		if (freqs->new < freqs->old)
127 			sa1100_pcmcia_set_mecr(skt, freqs->new);
128 		break;
129 	case CPUFREQ_RESUMECHANGE:
130 		sa1100_pcmcia_set_mecr(skt, freqs->new);
131 		break;
132 	}
133 
134 	return 0;
135 }
136 
137 #endif
138 
139 static int
140 sa1100_pcmcia_set_timing(struct soc_pcmcia_socket *skt)
141 {
142 	return sa1100_pcmcia_set_mecr(skt, cpufreq_get(0));
143 }
144 
145 static int
146 sa1100_pcmcia_show_timing(struct soc_pcmcia_socket *skt, char *buf)
147 {
148 	struct soc_pcmcia_timing timing;
149 	unsigned int clock = cpufreq_get(0);
150 	unsigned long mecr = MECR;
151 	char *p = buf;
152 
153 	soc_common_pcmcia_get_timing(skt, &timing);
154 
155 	p+=sprintf(p, "I/O      : %u (%u)\n", timing.io,
156 		   sa1100_pcmcia_cmd_time(clock, MECR_BSIO_GET(mecr, skt->nr)));
157 
158 	p+=sprintf(p, "attribute: %u (%u)\n", timing.attr,
159 		   sa1100_pcmcia_cmd_time(clock, MECR_BSA_GET(mecr, skt->nr)));
160 
161 	p+=sprintf(p, "common   : %u (%u)\n", timing.mem,
162 		   sa1100_pcmcia_cmd_time(clock, MECR_BSM_GET(mecr, skt->nr)));
163 
164 	return p - buf;
165 }
166 
167 int sa11xx_drv_pcmcia_probe(struct device *dev, struct pcmcia_low_level *ops,
168 			    int first, int nr)
169 {
170 	/*
171 	 * set default MECR calculation if the board specific
172 	 * code did not specify one...
173 	 */
174 	if (!ops->get_timing)
175 		ops->get_timing = sa1100_pcmcia_default_mecr_timing;
176 
177 	/* Provide our SA11x0 specific timing routines. */
178 	ops->set_timing  = sa1100_pcmcia_set_timing;
179 	ops->show_timing = sa1100_pcmcia_show_timing;
180 #ifdef CONFIG_CPU_FREQ
181 	ops->frequency_change = sa1100_pcmcia_frequency_change;
182 #endif
183 
184 	return soc_common_drv_pcmcia_probe(dev, ops, first, nr);
185 }
186 EXPORT_SYMBOL(sa11xx_drv_pcmcia_probe);
187 
188 static int __init sa11xx_pcmcia_init(void)
189 {
190 	return 0;
191 }
192 module_init(sa11xx_pcmcia_init);
193 
194 static void __exit sa11xx_pcmcia_exit(void) {}
195 
196 module_exit(sa11xx_pcmcia_exit);
197 
198 MODULE_AUTHOR("John Dorsey <john+@cs.cmu.edu>");
199 MODULE_DESCRIPTION("Linux PCMCIA Card Services: SA-11xx core socket driver");
200 MODULE_LICENSE("Dual MPL/GPL");
201