include/linux/mca.h

   1 /*
   2  * Header for Microchannel Architecture Bus
   3  * Written by Martin Kolinek, February 1996
   4  */
   5
   6 #ifndef _LINUX_MCA_H
   7 #define _LINUX_MCA_H
   8
   9 /* The detection of MCA bus is done in the real mode (using BIOS).
  10  * The information is exported to the protected code, where this
  11  * variable is set to one in case MCA bus was detected.
  12  */
  13 #ifndef MCA_bus__is_a_macro
  14 extern int  MCA_bus;
  15 #endif
  16
  17 /* Maximal number of MCA slots - actually, some machines have less, but
  18  * they all have sufficient number of POS registers to cover 8.
  19  */
  20 #define MCA_MAX_SLOT_NR  8
  21
  22 /* MCA_NOTFOUND is an error condition.  The other two indicate
  23  * motherboard POS registers contain the adapter.  They might be
  24  * returned by the mca_find_adapter() function, and can be used as
  25  * arguments to mca_read_stored_pos().  I'm not going to allow direct
  26  * access to the motherboard registers until we run across an adapter
  27  * that requires it.  We don't know enough about them to know if it's
  28  * safe.
  29  *
  30  * See Documentation/mca.txt or one of the existing drivers for
  31  * more information.
  32  */
  33 #define MCA_NOTFOUND    (-1)
  34 #define MCA_INTEGSCSI   (MCA_MAX_SLOT_NR)
  35 #define MCA_INTEGVIDEO  (MCA_MAX_SLOT_NR+1)
  36 #define MCA_MOTHERBOARD (MCA_MAX_SLOT_NR+2)
  37
  38 /* Max number of adapters, including both slots and various integrated
  39  * things.
  40  */
  41 #define MCA_NUMADAPTERS (MCA_MAX_SLOT_NR+3)
  42
  43 /* Returns the slot of the first enabled adapter matching id.  User can
  44  * specify a starting slot beyond zero, to deal with detecting multiple
  45  * devices.  Returns MCA_NOTFOUND if id not found.  Also checks the
  46  * integrated adapters.
  47  */
  48 extern int mca_find_adapter(int id, int start);
  49 extern int mca_find_unused_adapter(int id, int start);
  50
  51 /* adapter state info - returns 0 if no */
  52 extern int mca_isadapter(int slot);
  53 extern int mca_isenabled(int slot);
  54
  55 extern int mca_is_adapter_used(int slot);
  56 extern int mca_mark_as_used(int slot);
  57 extern void mca_mark_as_unused(int slot);
  58
  59 /* gets a byte out of POS register (stored in memory) */
  60 extern unsigned char mca_read_stored_pos(int slot, int reg);
  61
  62 /* This can be expanded later.  Right now, it gives us a way of
  63  * getting meaningful information into the MCA_info structure,
  64  * so we can have a more interesting /proc/mca.
  65  */
  66 extern void mca_set_adapter_name(int slot, char* name);
  67 extern char* mca_get_adapter_name(int slot);
  68
  69 /* This sets up an information callback for /proc/mca/slot?.  The
  70  * function is called with the buffer, slot, and device pointer (or
  71  * some equally informative context information, or nothing, if you
  72  * prefer), and is expected to put useful information into the
  73  * buffer.  The adapter name, id, and POS registers get printed
  74  * before this is called though, so don't do it again.
  75  *
  76  * This should be called with a NULL procfn when a module
  77  * unregisters, thus preventing kernel crashes and other such
  78  * nastiness.
  79  */
  80 typedef int (*MCA_ProcFn)(char* buf, int slot, void* dev);
  81 extern void mca_set_adapter_procfn(int slot, MCA_ProcFn, void* dev);
  82
  83 /* These routines actually mess with the hardware POS registers.  They
  84  * temporarily disable the device (and interrupts), so make sure you know
  85  * what you're doing if you use them.  Furthermore, writing to a POS may
  86  * result in two devices trying to share a resource, which in turn can
  87  * result in multiple devices sharing memory spaces, IRQs, or even trashing
  88  * hardware.  YOU HAVE BEEN WARNED.
  89  *
  90  * You can only access slots with this.  Motherboard registers are off
  91  * limits.
  92  */
  93
  94 /* read a byte from the specified POS register. */
  95 extern unsigned char mca_read_pos(int slot, int reg);
  96
  97 /* write a byte to the specified POS register. */
  98 extern void mca_write_pos(int slot, int reg, unsigned char byte);
  99
 100 /* Should only be called by the NMI interrupt handler, this will do some
 101  * fancy stuff to figure out what might have generated a NMI.
 102  */
 103 extern void mca_handle_nmi(void);
 104
 105 #endif /* _LINUX_MCA_H */