drivers/pcmcia/sa11xx_base.c

   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");