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/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");