ioperm.c

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/* Copyright (C) 1992, 1996-1999, 2000 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by David Mosberger.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* I/O access is restricted to ISA port space (ports 0..65535).
   Modern devices hopefully are sane enough not to put any performance
   critical registers in i/o space.

   On the first call to ioperm, the entire (E)ISA port space is mapped
   into the virtual address space at address io.base.  mprotect calls
   are then used to enable/disable access to ports.  Per page, there
   are PAGE_SIZE>>IO_SHIFT I/O ports (e.g., 256 ports on a Low Cost Alpha
   based system using 8KB pages).

   Keep in mind that this code should be able to run in a 32bit address
   space.  It is therefore unreasonable to expect mmap'ing the entire
   sparse address space would work (e.g., the Low Cost Alpha chip has an
   I/O address space that's 512MB large!).  */

/* Make sure the ldbu/stb asms below are not expaneded to macros.  */
#ifndef __alpha_bwx__
asm(".arch ev56");
#endif

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <sys/types.h>
#include <sys/mman.h>
#include <sys/io.h>

#include <sysdep.h>
#include <sys/syscall.h>

#define PATH_ALPHA_SYSTYPE	"/etc/alpha_systype"
#define PATH_CPUINFO		"/proc/cpuinfo"

#define MAX_PORT	0x10000
#define vip		volatile int *
#define vuip		volatile unsigned int *
#define vusp		volatile unsigned short *
#define vucp		volatile unsigned char *

#define JENSEN_IO_BASE		(0x300000000UL)
#define JENSEN_SPARSE_MEM	(0x200000000UL)

/* With respect to the I/O architecture, APECS and LCA are identical,
   so the following defines apply to LCA as well.  */
#define APECS_IO_BASE		(0x1c0000000UL)
#define APECS_SPARSE_MEM	(0x200000000UL)
#define APECS_DENSE_MEM		(0x300000000UL)

/* The same holds for CIA and PYXIS, except for PYXIS we prefer BWX.  */
#define CIA_IO_BASE		(0x8580000000UL)
#define CIA_SPARSE_MEM		(0x8000000000UL)
#define CIA_DENSE_MEM		(0x8600000000UL)

#define PYXIS_IO_BASE		(0x8900000000UL)
#define PYXIS_DENSE_MEM		(0x8800000000UL)

/* SABLE is EV4, GAMMA is EV5 */
#define T2_IO_BASE		(0x3a0000000UL)
#define T2_SPARSE_MEM		(0x200000000UL)
#define T2_DENSE_MEM		(0x3c0000000UL)

#define GAMMA_IO_BASE		(0x83a0000000UL)
#define GAMMA_SPARSE_MEM	(0x8200000000UL)
#define GAMMA_DENSE_MEM		(0x83c0000000UL)

/* NOTE: these are hardwired to PCI bus 0 addresses!!! */
#define MCPCIA_IO_BASE		(0xf980000000UL)
#define MCPCIA_SPARSE_MEM	(0xf800000000UL)
#define MCPCIA_DENSE_MEM	(0xf900000000UL)

/* Tsunami and Irongate use the same offsets, at least for hose 0.  */
#define TSUNAMI_IO_BASE		(0x801fc000000UL)
#define TSUNAMI_DENSE_MEM	(0x80000000000UL)

/* Polaris has SPARSE space, but we prefer to use only DENSE
   because of some idiosyncracies in actually using SPARSE.  */
#define POLARIS_IO_BASE		(0xf9fc000000UL)
#define POLARIS_DENSE_MEM	(0xf900000000UL)

typedef enum {
  IOSYS_UNKNOWN, IOSYS_JENSEN, IOSYS_APECS, IOSYS_CIA, IOSYS_PYXIS, IOSYS_T2,
  IOSYS_TSUNAMI, IOSYS_MCPCIA, IOSYS_GAMMA, IOSYS_POLARIS,
  IOSYS_CPUDEP, IOSYS_PCIDEP
} iosys_t;

typedef enum {
  IOSWIZZLE_JENSEN, IOSWIZZLE_SPARSE, IOSWIZZLE_DENSE
} ioswizzle_t;

static struct io_system {
  unsigned long	int bus_memory_base;
  unsigned long	int sparse_bus_mem_base;
  unsigned long	int bus_io_base;
} io_system[] = { /* NOTE! must match iosys_t enumeration */
/* UNKNOWN */	{0, 0, 0},
/* JENSEN */	{0, JENSEN_SPARSE_MEM, JENSEN_IO_BASE},
/* APECS */	{APECS_DENSE_MEM, APECS_SPARSE_MEM, APECS_IO_BASE},
/* CIA */	{CIA_DENSE_MEM, CIA_SPARSE_MEM, CIA_IO_BASE},
/* PYXIS */	{PYXIS_DENSE_MEM, 0, PYXIS_IO_BASE},
/* T2 */	{T2_DENSE_MEM, T2_SPARSE_MEM, T2_IO_BASE},
/* TSUNAMI */	{TSUNAMI_DENSE_MEM, 0, TSUNAMI_IO_BASE},
/* MCPCIA */	{MCPCIA_DENSE_MEM, MCPCIA_SPARSE_MEM, MCPCIA_IO_BASE},
/* GAMMA */	{GAMMA_DENSE_MEM, GAMMA_SPARSE_MEM, GAMMA_IO_BASE},
/* POLARIS */	{POLARIS_DENSE_MEM, 0, POLARIS_IO_BASE},
/* CPUDEP */	{0, 0, 0}, /* for platforms dependent on CPU type */
/* PCIDEP */	{0, 0, 0}, /* for platforms dependent on core logic */
};

static struct platform {
  const char	   *name;
  iosys_t	    io_sys;
} platform[] = {
  {"Alcor",	IOSYS_CIA},
  {"Avanti",	IOSYS_APECS},
  {"Cabriolet",	IOSYS_APECS},
  {"EB164",	IOSYS_PCIDEP},
  {"EB64+",	IOSYS_APECS},
  {"EB66",	IOSYS_APECS},
  {"EB66P",	IOSYS_APECS},
  {"Jensen",	IOSYS_JENSEN},
  {"Miata",	IOSYS_PYXIS},
  {"Mikasa",	IOSYS_CPUDEP},
  {"Nautilus",	IOSYS_TSUNAMI},
  {"Noname",	IOSYS_APECS},
  {"Noritake",	IOSYS_CPUDEP},
  {"Rawhide",	IOSYS_MCPCIA},
  {"Ruffian",	IOSYS_PYXIS},
  {"Sable",	IOSYS_CPUDEP},
  {"Takara",	IOSYS_CIA},
  {"Tsunami",	IOSYS_TSUNAMI},
  {"XL",	IOSYS_APECS},
};

struct ioswtch {
  void		(*sethae)(unsigned long int addr);
  void		(*outb)(unsigned char b, unsigned long int port);
  void		(*outw)(unsigned short b, unsigned long int port);
  void		(*outl)(unsigned int b, unsigned long int port);
  unsigned int	(*inb)(unsigned long int port);
  unsigned int	(*inw)(unsigned long int port);
  unsigned int	(*inl)(unsigned long int port);
};

static struct {
  unsigned long int hae_cache;
  unsigned long int	base;
  struct ioswtch *	swp;
  unsigned long int	bus_memory_base;
  unsigned long int	sparse_bus_memory_base;
  unsigned long int	io_base;
  ioswizzle_t		swiz;
} io;

static inline void
stb_mb(unsigned char val, unsigned long addr)
{
  __asm__("stb %1,%0; mb" : "=m"(*(vucp)addr) : "r"(val));
}

static inline void
stw_mb(unsigned short val, unsigned long addr)
{
  __asm__("stw %1,%0; mb" : "=m"(*(vusp)addr) : "r"(val));
}

static inline void
stl_mb(unsigned int val, unsigned long addr)
{
  __asm__("stl %1,%0; mb" : "=m"(*(vip)addr) : "r"(val));
}

/* No need to examine error -- sethae never fails.  */
static inline void
__sethae(unsigned long value)
{
  register unsigned long r16 __asm__("$16") = value;
  register unsigned long r0 __asm__("$0") = __NR_sethae;
  __asm__ __volatile__ ("callsys"
			: "=r"(r0)
			: "0"(r0), "r" (r16)
			: inline_syscall_clobbers, "$19");
}

extern long __pciconfig_iobase(enum __pciconfig_iobase_which __which,
			       unsigned long int __bus,
			       unsigned long int __dfn);

static inline unsigned long int
port_to_cpu_addr (unsigned long int port, ioswizzle_t ioswiz, int size)
{
  if (ioswiz == IOSWIZZLE_SPARSE)
    return io.base + (port << 5) + ((size - 1) << 3);
  else if (ioswiz == IOSWIZZLE_DENSE)
    return port + io.base;
  else
    return io.base + (port << 7) + ((size - 1) << 5);
}

static inline void
inline_sethae (unsigned long int addr, ioswizzle_t ioswiz)
{
  if (ioswiz == IOSWIZZLE_SPARSE)
    {
      unsigned long int msb;

      /* no need to set hae if msb is 0: */
      msb = addr & 0xf8000000;
      if (msb && msb != io.hae_cache)
	{
	  io.hae_cache = msb;
	  __sethae (msb);
	}
    }
  else if (ioswiz == IOSWIZZLE_JENSEN)
    {
      /* HAE on the Jensen is bits 31:25 shifted right.  */
      addr >>= 25;
      if (addr != io.hae_cache)
	{
	  io.hae_cache = addr;
	  __sethae (addr);
	}
    }
}

static inline void
inline_outb (unsigned char b, unsigned long int port, ioswizzle_t ioswiz)
{
  unsigned int w;
  unsigned long int addr = port_to_cpu_addr (port, ioswiz, 1);

  asm ("insbl %2,%1,%0" : "=r" (w) : "ri" (port & 0x3), "r" (b));
  stl_mb(w, addr);
}


static inline void
inline_outw (unsigned short int b, unsigned long int port, ioswizzle_t ioswiz)
{
  unsigned long w;
  unsigned long int addr = port_to_cpu_addr (port, ioswiz, 2);

  asm ("inswl %2,%1,%0" : "=r" (w) : "ri" (port & 0x3), "r" (b));
  stl_mb(w, addr);
}


static inline void
inline_outl (unsigned int b, unsigned long int port, ioswizzle_t ioswiz)
{
  unsigned long int addr = port_to_cpu_addr (port, ioswiz, 4);

  stl_mb(b, addr);
}


static inline unsigned int
inline_inb (unsigned long int port, ioswizzle_t ioswiz)
{
  unsigned long int addr = port_to_cpu_addr (port, ioswiz, 1);
  int result;

  result = *(vip) addr;
  result >>= (port & 3) * 8;
  return 0xffUL & result;
}


static inline unsigned int
inline_inw (unsigned long int port, ioswizzle_t ioswiz)
{
  unsigned long int addr = port_to_cpu_addr (port, ioswiz, 2);
  int result;

  result = *(vip) addr;
  result >>= (port & 3) * 8;
  return 0xffffUL & result;
}


static inline unsigned int
inline_inl (unsigned long int port, ioswizzle_t ioswiz)
{
  unsigned long int addr = port_to_cpu_addr (port, ioswiz, 4);

  return *(vuip) addr;
}

/*
 * Now define the inline functions for CPUs supporting byte/word insns,
 * and whose core logic supports I/O space accesses utilizing them.
 *
 * These routines could be used by MIATA, for example, because it has
 * and EV56 plus PYXIS, but it currently uses SPARSE anyway. This is
 * also true of RX164 which used POLARIS, but we will choose to use
 * these routines in that case instead of SPARSE.
 *
 * These routines are necessary for TSUNAMI/TYPHOON based platforms,
 * which will have (at least) EV6.
 */

static inline unsigned long int
dense_port_to_cpu_addr (unsigned long int port)
{
  return port + io.base;
}

static inline void
inline_bwx_outb (unsigned char b, unsigned long int port)
{
  unsigned long int addr = dense_port_to_cpu_addr (port);
  stb_mb (b, addr);
}

static inline void
inline_bwx_outw (unsigned short int b, unsigned long int port)
{
  unsigned long int addr = dense_port_to_cpu_addr (port);
  stw_mb (b, addr);
}

static inline void
inline_bwx_outl (unsigned int b, unsigned long int port)
{
  unsigned long int addr = dense_port_to_cpu_addr (port);
  stl_mb (b, addr);
}

static inline unsigned int
inline_bwx_inb (unsigned long int port)
{
  unsigned long int addr = dense_port_to_cpu_addr (port);
  unsigned char r;

  __asm__ ("ldbu %0,%1" : "=r"(r) : "m"(*(vucp)addr));
  return r;
}

static inline unsigned int
inline_bwx_inw (unsigned long int port)
{
  unsigned long int addr = dense_port_to_cpu_addr (port);
  unsigned short r;

  __asm__ ("ldwu %0,%1" : "=r"(r) : "m"(*(vusp)addr));
  return r;
}

static inline unsigned int
inline_bwx_inl (unsigned long int port)
{
  unsigned long int addr = dense_port_to_cpu_addr (port);

  return *(vuip) addr;
}

/* macros to define routines with appropriate names and functions */

/* these do either SPARSE or JENSEN swizzle */

#define DCL_SETHAE(name, ioswiz)                        \
static void                                             \
name##_sethae (unsigned long int addr)                  \
{                                                       \
  inline_sethae (addr, IOSWIZZLE_##ioswiz);             \
}

#define DCL_OUT(name, func, type, ioswiz)		\
static void						\
name##_##func (unsigned type b, unsigned long int addr)	\
{							\
  inline_##func (b, addr, IOSWIZZLE_##ioswiz);		\
}

#define DCL_IN(name, func, ioswiz)			\
static unsigned int					\
name##_##func (unsigned long int addr)			\
{							\
  return inline_##func (addr, IOSWIZZLE_##ioswiz);	\
}

/* these do DENSE, so no swizzle is needed */

#define DCL_OUT_BWX(name, func, type)			\
static void						\
name##_##func (unsigned type b, unsigned long int addr)	\
{							\
  inline_bwx_##func (b, addr);				\
}

#define DCL_IN_BWX(name, func)				\
static unsigned int					\
name##_##func (unsigned long int addr)			\
{							\
  return inline_bwx_##func (addr);			\
}

/* now declare/define the necessary routines */

DCL_SETHAE(jensen, JENSEN)
DCL_OUT(jensen, outb, char,  JENSEN)
DCL_OUT(jensen, outw, short int, JENSEN)
DCL_OUT(jensen, outl, int,   JENSEN)
DCL_IN(jensen, inb, JENSEN)
DCL_IN(jensen, inw, JENSEN)
DCL_IN(jensen, inl, JENSEN)

DCL_SETHAE(sparse, SPARSE)
DCL_OUT(sparse, outb, char,  SPARSE)
DCL_OUT(sparse, outw, short int, SPARSE)
DCL_OUT(sparse, outl, int,   SPARSE)
DCL_IN(sparse, inb, SPARSE)
DCL_IN(sparse, inw, SPARSE)
DCL_IN(sparse, inl, SPARSE)

DCL_SETHAE(dense, DENSE)
DCL_OUT_BWX(dense, outb, char)
DCL_OUT_BWX(dense, outw, short int)