drivers/ssb/pcmcia.c

   1 /*
   2  * Sonics Silicon Backplane
   3  * PCMCIA-Hostbus related functions
   4  *
   5  * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
   6  * Copyright 2007 Michael Buesch <mb@bu3sch.de>
   7  *
   8  * Licensed under the GNU/GPL. See COPYING for details.
   9  */
  10
  11 #include <linux/ssb/ssb.h>
  12 #include <linux/delay.h>
  13 #include <linux/io.h>
  14
  15 #include <pcmcia/cs_types.h>
  16 #include <pcmcia/cs.h>
  17 #include <pcmcia/cistpl.h>
  18 #include <pcmcia/ciscode.h>
  19 #include <pcmcia/ds.h>
  20 #include <pcmcia/cisreg.h>
  21
  22 #include "ssb_private.h"
  23
  24
  25 /* Define the following to 1 to enable a printk on each coreswitch. */
  26 #define SSB_VERBOSE_PCMCIACORESWITCH_DEBUG              0
  27
  28
  29 int ssb_pcmcia_switch_coreidx(struct ssb_bus *bus,
  30                               u8 coreidx)
  31 {
  32         struct pcmcia_device *pdev = bus->host_pcmcia;
  33         int err;
  34         int attempts = 0;
  35         u32 cur_core;
  36         conf_reg_t reg;
  37         u32 addr;
  38         u32 read_addr;
  39
  40         addr = (coreidx * SSB_CORE_SIZE) + SSB_ENUM_BASE;
  41         while (1) {
  42                 reg.Action = CS_WRITE;
  43                 reg.Offset = 0x2E;
  44                 reg.Value = (addr & 0x0000F000) >> 12;
  45                 err = pcmcia_access_configuration_register(pdev, &reg);
  46                 if (err != CS_SUCCESS)
  47                         goto error;
  48                 reg.Offset = 0x30;
  49                 reg.Value = (addr & 0x00FF0000) >> 16;
  50                 err = pcmcia_access_configuration_register(pdev, &reg);
  51                 if (err != CS_SUCCESS)
  52                         goto error;
  53                 reg.Offset = 0x32;
  54                 reg.Value = (addr & 0xFF000000) >> 24;
  55                 err = pcmcia_access_configuration_register(pdev, &reg);
  56                 if (err != CS_SUCCESS)
  57                         goto error;
  58
  59                 read_addr = 0;
  60
  61                 reg.Action = CS_READ;
  62                 reg.Offset = 0x2E;
  63                 err = pcmcia_access_configuration_register(pdev, &reg);
  64                 if (err != CS_SUCCESS)
  65                         goto error;
  66                 read_addr |= (reg.Value & 0xF) << 12;
  67                 reg.Offset = 0x30;
  68                 err = pcmcia_access_configuration_register(pdev, &reg);
  69                 if (err != CS_SUCCESS)
  70                         goto error;
  71                 read_addr |= reg.Value << 16;
  72                 reg.Offset = 0x32;
  73                 err = pcmcia_access_configuration_register(pdev, &reg);
  74                 if (err != CS_SUCCESS)
  75                         goto error;
  76                 read_addr |= reg.Value << 24;
  77
  78                 cur_core = (read_addr - SSB_ENUM_BASE) / SSB_CORE_SIZE;
  79                 if (cur_core == coreidx)
  80                         break;
  81
  82                 if (attempts++ > SSB_BAR0_MAX_RETRIES)
  83                         goto error;
  84                 udelay(10);
  85         }
  86
  87         return 0;
  88 error:
  89         ssb_printk(KERN_ERR PFX "Failed to switch to core %u\n", coreidx);
  90         return -ENODEV;
  91 }
  92
  93 int ssb_pcmcia_switch_core(struct ssb_bus *bus,
  94                            struct ssb_device *dev)
  95 {
  96         int err;
  97         unsigned long flags;
  98
  99 #if SSB_VERBOSE_PCMCIACORESWITCH_DEBUG
 100         ssb_printk(KERN_INFO PFX
 101                    "Switching to %s core, index %d\n",
 102                    ssb_core_name(dev->id.coreid),
 103                    dev->core_index);
 104 #endif
 105
 106         spin_lock_irqsave(&bus->bar_lock, flags);
 107         err = ssb_pcmcia_switch_coreidx(bus, dev->core_index);
 108         if (!err)
 109                 bus->mapped_device = dev;
 110         spin_unlock_irqrestore(&bus->bar_lock, flags);
 111
 112         return err;
 113 }
 114
 115 int ssb_pcmcia_switch_segment(struct ssb_bus *bus, u8 seg)
 116 {
 117         int attempts = 0;
 118         unsigned long flags;
 119         conf_reg_t reg;
 120         int res, err = 0;
 121
 122         SSB_WARN_ON((seg != 0) && (seg != 1));
 123         reg.Offset = 0x34;
 124         reg.Function = 0;
 125         spin_lock_irqsave(&bus->bar_lock, flags);
 126         while (1) {
 127                 reg.Action = CS_WRITE;
 128                 reg.Value = seg;
 129                 res = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
 130                 if (unlikely(res != CS_SUCCESS))
 131                         goto error;
 132                 reg.Value = 0xFF;
 133                 reg.Action = CS_READ;
 134                 res = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
 135                 if (unlikely(res != CS_SUCCESS))
 136                         goto error;
 137
 138                 if (reg.Value == seg)
 139                         break;
 140
 141                 if (unlikely(attempts++ > SSB_BAR0_MAX_RETRIES))
 142                         goto error;
 143                 udelay(10);
 144         }
 145         bus->mapped_pcmcia_seg = seg;
 146 out_unlock:
 147         spin_unlock_irqrestore(&bus->bar_lock, flags);
 148         return err;
 149 error:
 150         ssb_printk(KERN_ERR PFX "Failed to switch pcmcia segment\n");
 151         err = -ENODEV;
 152         goto out_unlock;
 153 }
 154
 155 /* These are the main device register access functions.
 156  * do_select_core is inline to have the likely hotpath inline.
 157  * All unlikely codepaths are out-of-line. */
 158 static inline int do_select_core(struct ssb_bus *bus,
 159                                  struct ssb_device *dev,
 160                                  u16 *offset)
 161 {
 162         int err;
 163         u8 need_seg = (*offset >= 0x800) ? 1 : 0;
 164
 165         if (unlikely(dev != bus->mapped_device)) {
 166                 err = ssb_pcmcia_switch_core(bus, dev);
 167                 if (unlikely(err))
 168                         return err;
 169         }
 170         if (unlikely(need_seg != bus->mapped_pcmcia_seg)) {
 171                 err = ssb_pcmcia_switch_segment(bus, need_seg);
 172                 if (unlikely(err))
 173                         return err;
 174         }
 175         if (need_seg == 1)
 176                 *offset -= 0x800;
 177
 178         return 0;
 179 }
 180
 181 static u16 ssb_pcmcia_read16(struct ssb_device *dev, u16 offset)
 182 {
 183         struct ssb_bus *bus = dev->bus;
 184         u16 x;
 185
 186         if (unlikely(do_select_core(bus, dev, &offset)))
 187                 return 0xFFFF;
 188         x = readw(bus->mmio + offset);
 189
 190         return x;
 191 }
 192
 193 static u32 ssb_pcmcia_read32(struct ssb_device *dev, u16 offset)
 194 {
 195         struct ssb_bus *bus = dev->bus;
 196         u32 x;
 197
 198         if (unlikely(do_select_core(bus, dev, &offset)))
 199                 return 0xFFFFFFFF;
 200         x = readl(bus->mmio + offset);
 201
 202         return x;
 203 }
 204
 205 static void ssb_pcmcia_write16(struct ssb_device *dev, u16 offset, u16 value)
 206 {
 207         struct ssb_bus *bus = dev->bus;
 208
 209         if (unlikely(do_select_core(bus, dev, &offset)))
 210                 return;
 211         writew(value, bus->mmio + offset);
 212 }
 213
 214 static void ssb_pcmcia_write32(struct ssb_device *dev, u16 offset, u32 value)
 215 {
 216         struct ssb_bus *bus = dev->bus;
 217
 218         if (unlikely(do_select_core(bus, dev, &offset)))
 219                 return;
 220         readw(bus->mmio + offset);
 221         writew(value >> 16, bus->mmio + offset + 2);
 222         readw(bus->mmio + offset);
 223         writew(value, bus->mmio + offset);
 224 }
 225
 226 /* Not "static", as it's used in main.c */
 227 const struct ssb_bus_ops ssb_pcmcia_ops = {
 228         .read16         = ssb_pcmcia_read16,
 229         .read32         = ssb_pcmcia_read32,
 230         .write16        = ssb_pcmcia_write16,
 231         .write32        = ssb_pcmcia_write32,
 232 };
 233
 234 int ssb_pcmcia_get_invariants(struct ssb_bus *bus,
 235                               struct ssb_init_invariants *iv)
 236 {
 237         //TODO
 238         return 0;
 239 }
 240
 241 int ssb_pcmcia_init(struct ssb_bus *bus)
 242 {
 243         conf_reg_t reg;
 244         int err;
 245
 246         if (bus->bustype != SSB_BUSTYPE_PCMCIA)
 247                 return 0;
 248
 249         /* Switch segment to a known state and sync
 250          * bus->mapped_pcmcia_seg with hardware state. */
 251         ssb_pcmcia_switch_segment(bus, 0);
 252
 253         /* Init IRQ routing */
 254         reg.Action = CS_READ;
 255         reg.Function = 0;
 256         if (bus->chip_id == 0x4306)
 257                 reg.Offset = 0x00;
 258         else
 259                 reg.Offset = 0x80;
 260         err = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
 261         if (err != CS_SUCCESS)
 262                 goto error;
 263         reg.Action = CS_WRITE;
 264         reg.Value |= 0x04 | 0x01;
 265         err = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
 266         if (err != CS_SUCCESS)
 267                 goto error;
 268
 269         return 0;
 270 error:
 271         return -ENODEV;
 272 }