R6.6 is the Xorg base-line

hw/xfree86/os-support/shared/bios_devmem.c

@@ -0,0 +1,139 @@
+/* $XFree86: xc/programs/Xserver/hw/xfree86/os-support/shared/bios_devmem.c,v 3.3 1996/12/23 06:50:58 dawes Exp $ */
+/*
+ * Copyright 1993 by David Wexelblat <dwex@goblin.org>
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of David Wexelblat not be used in
+ * advertising or publicity pertaining to distribution of the software without
+ * specific, written prior permission.  David Wexelblat makes no representations
+ * about the suitability of this software for any purpose.  It is provided
+ * "as is" without express or implied warranty.
+ *
+ * DAVID WEXELBLAT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL DAVID WEXELBLAT BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+/* $Xorg: bios_devmem.c,v 1.3 2000/08/17 19:51:30 cpqbld Exp $ */
+
+#include "X.h"
+#include "input.h"
+#include "scrnintstr.h"
+
+#include "xf86.h"
+#include "xf86Priv.h"
+#include "xf86_OSlib.h"
+#include <string.h>
+
+/*
+ * Read BIOS via /dev/mem.
+ */
+
+#ifndef DEV_MEM
+# define DEV_MEM "/dev/mem"
+#endif
+
+int xf86ReadBIOS(Base, Offset, Buf, Len)
+unsigned long Base;
+unsigned long Offset;
+unsigned char *Buf;
+int Len;
+{
+#ifdef __alpha__
+  /*
+   * The Alpha version uses "mmap" instead of "lseek/read",
+   *  because these (currently) don't work for BUS memory.
+   * We trick "mmap" into mapping BUS memory for us via BUS_BASE,
+   *  which is the KSEG address of the start of the DENSE memory
+   *  area.
+   */
+
+  /*
+   * NOTE: there prolly ought to be more validity checks and all
+   *  re: boundaries and sizes and such...
+   */
+
+/*
+ * The Jensen lacks dense memory, thus we have to address the bus via
+ * the sparse addressing scheme.
+ *
+ * Martin Ostermann (ost@comnets.rwth-aachen.de) - Apr.-Sep. 1996
+ */
+
+#ifdef TEST_JENSEN_CODE /* define to test the Sparse addressing on a non-Jensen */
+#define SPARSE (5)
+#define isJensen (1)
+#else
+#define isJensen (!_bus_base())
+#define SPARSE (7)
+#endif
+
+extern unsigned long _bus_base(void);
+extern unsigned long _bus_base_sparse(void);
+#define BUS_BASE (isJensen ? _bus_base_sparse() : _bus_base())
+#define JENSEN_SHIFT(x) (isJensen ? ((long)x<<SPARSE) : (long)x)
+
+#define SIZE (64*1024)
+
+	caddr_t base;
+ 	int fd;
+
+	if ((fd = open(DEV_MEM, O_RDONLY)) < 0)
+	{
+		ErrorF("xf86ReadBios: Failed to open %s (%s)\n", DEV_MEM,
+		       strerror(errno));
+		return(-1);
+	}
+
+	base = mmap((caddr_t)0, JENSEN_SHIFT(SIZE), PROT_READ,
+		    MAP_SHARED, fd, (off_t)(JENSEN_SHIFT(Base) + BUS_BASE));
+
+	if (base == (caddr_t)-1UL)
+	{
+		ErrorF("xf86ReadBios: Failed to mmap %s (%s)\n", DEV_MEM,
+		       strerror(errno));
+		return(-1);
+	}
+
+	SlowBCopyFromBus(base+JENSEN_SHIFT(Offset), Buf, Len);
+
+	munmap((caddr_t)JENSEN_SHIFT(base), JENSEN_SHIFT(SIZE));
+	close(fd);
+	return(Len);
+
+#else /* __alpha__ */
+
+ 	int fd;
+
+	if ((fd = open(DEV_MEM, O_RDONLY)) < 0)
+	{
+		ErrorF("xf86ReadBios: Failed to open %s (%s)\n", DEV_MEM,
+		       strerror(errno));
+		return(-1);
+	}
+
+	if (lseek(fd, (Base+Offset), SEEK_SET) < 0)
+	{
+		ErrorF("xf86ReadBios: %s seek failed (%s)\n", DEV_MEM,
+		       strerror(errno));
+		close(fd);
+		return(-1);
+	}
+	if (read(fd, Buf, Len) != Len)
+	{
+		ErrorF("xf86ReadBios: %s read failed (%s)\n", DEV_MEM,
+		       strerror(errno));
+		close(fd);
+		return(-1);
+	}
+	close(fd);
+	return(Len);
+#endif /* __alpha__ */
+}