Support functions for working with x86 PC-architecture BIOS.

Initially functionality is confined to 32-bit BIOS functions, however
it is envisioned that BIOS support may be enlisted for other
activities in the future.

3 files changed, 521 insertions, 0 deletions

diff --git a/sys/amd64/amd64/bios.c b/sys/amd64/amd64/bios.c
new file mode 100644
index 0000000..256bb8b
--- /dev/null
+++ b/sys/amd64/amd64/bios.c
@@ -0,0 +1,231 @@
+/*-
+ * Copyright (c) 1997 Michael Smith
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *      $Id$
+ */
+
+/*
+ * Code for dealing with the BIOS in x86 PC systems.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <vm/vm.h>
+#include <vm/pmap.h>
+#include <machine/pmap.h>
+#include <machine/md_var.h>
+
+#include <machine/pc/bios.h>
+
+#define BIOS_START	0xe0000
+#define BIOS_SIZE	0x20000
+
+/* exported lookup results */
+struct bios32_SDentry	PCIbios = {entry : 0};
+struct SMBIOS_table	*SMBIOStable = 0;
+struct DMI_table	*DMItable = 0;
+
+static caddr_t		bios32_SDCI = NULL;
+
+static void		bios32_init(void *junk);
+
+/* start fairly early */
+SYSINIT(bios32, SI_SUB_CPU, SI_ORDER_ANY, bios32_init, NULL);
+
+/*
+ * bios32_init
+ *
+ * Locate various bios32 entities.
+ */
+static void
+bios32_init(void *junk)
+{
+    u_long			sigaddr;
+    struct bios32_SDheader	*sdh;
+    struct SMBIOS_table		*sbt;
+    struct DMI_table		*dmit;
+    u_int8_t			ck, *cv;
+    int				i;
+    
+
+    /*
+     * BIOS32 Service Directory
+     */
+    
+    /* look for the signature */
+    if ((sigaddr = bios_sigsearch(0, "_32_", 4, 16, 0)) != 0) {
+
+	/* get a virtual pointer to the structure */
+	sdh = (struct bios32_SDheader *)BIOS_PADDRTOVADDR(sigaddr);
+	for (cv = (u_int8_t *)sdh, ck = 0, i = 0; i < (sdh->len * 16); i++) {
+	    ck += cv[i];
+	}
+	/* If checksum is OK, enable use of the entrypoint */
+	if (ck == 0) {
+	    bios32_SDCI = (caddr_t)BIOS_PADDRTOVADDR(sdh->entry);
+	    if (bootverbose) {
+		printf("Found BIOS32 Service Directory header at %p\n", sdh);
+		printf("Entry = 0x%x (%p)  Rev = %d  Len = %d\n", 
+		       sdh->entry, bios32_SDCI, sdh->revision, sdh->len);
+	    }
+	    /* See if there's a PCI BIOS entrypoint here */
+	    PCIbios.ident.id = 0x49435024;	/* PCI systems should have this */
+	    if (!bios32_SDlookup(&PCIbios) && bootverbose)
+		printf("PCI BIOS entry at 0x%x\n", PCIbios.entry);
+	} else {
+	    printf("Bad BIOS32 Service Directory!\n");
+	}
+    }
+
+    /*
+     * System Management BIOS
+     */
+    /* look for the SMBIOS signature */
+    if ((sigaddr = bios_sigsearch(0, "_SM_", 4, 16, 0)) != 0) {
+
+	/* get a virtual pointer to the structure */
+	sbt = (struct SMBIOS_table *)BIOS_PADDRTOVADDR(sigaddr);
+	for (cv = (u_int8_t *)sbt, ck = 0, i = 0; i < sbt->len; i++) {
+	    ck += cv[i];
+	}
+	/* if checksum is OK, we have action */
+	if (ck == 0) {
+	    SMBIOStable = sbt;		/* save reference */
+	    DMItable = &sbt->dmi;	/* contained within */
+	    if (bootverbose) {
+		printf("SMIBIOS header at %p\n", sbt);
+		printf("Version %d.%d\n", sbt->major, sbt->minor);
+		printf("Table at 0x%x, %hd entries, %hd bytes, largest entry %hd bytes\n",
+		       dmit->st_base, dmit->st_entries, dmit->st_size, sbt->st_maxsize);
+	    }
+	} else {
+	    printf("Bad SMBIOS table checksum!\n");
+	}
+	
+    }
+    /* look for the DMI signature */
+    if ((sigaddr = bios_sigsearch(0, "_DMI_", 5, 16, 0)) != 0) {
+
+	/* get a virtual pointer to the structure */
+	dmit = (struct DMI_table *)BIOS_PADDRTOVADDR(sigaddr);
+	for (cv = (u_int8_t *)dmit, ck = 0, i = 0; i < 16; i++) {
+	    ck += cv[i];
+	}
+	/* if checksum is OK, we have action */
+	if (ck == 0) {
+	    DMItable = dmit;		/* save reference */
+	    if (bootverbose) {
+		printf("DMI header at %p\n", dmit);
+		printf("Version %x\n", dmit->bcd_revision);
+		printf("Table at 0x%x, %hd entries, %hd bytes\n",
+		       dmit->st_base, dmit->st_entries, dmit->st_size);
+	    }
+	} else {
+	    printf("Bad DMI table checksum!\n");
+	}
+    }
+
+}
+
+/*
+ * bios32_SDlookup
+ *
+ * Query the BIOS32 Service Directory for the service named in (ent),
+ * returns nonzero if the lookup fails.  The caller must fill in
+ * (ent->ident), the remainder are populated on a successful lookup.
+ */
+int
+bios32_SDlookup(struct bios32_SDentry *ent)
+{
+    struct bios32_args	args;
+    
+    if (bios32_SDCI != NULL) {
+
+	args.eax = ent->ident.id;		/* set up arguments */
+	args.ebx = args.ecx = args.edx = 0;
+	bios32(bios32_SDCI, &args);		/* make the BIOS call */
+	if ((args.eax & 0xff) == 0) {		/* success? */
+	    ent->base = args.ebx;
+	    ent->len = args.ecx;
+	    ent->entry = args.edx;
+	    return(0);				/* all OK */
+	}
+    }
+    return(1);					/* failed */
+}
+
+/*
+ * bios_sigsearch
+ *
+ * Search some or all of the BIOS region for a signature string.
+ *
+ * (start)	Optional offset returned from this function 
+ *		(for searching for multiple matches), or NULL
+ *		to start the search from the base of the BIOS.
+ *		Note that this will be a _physical_ address in
+ *		the range 0xe0000 - 0xfffff.
+ * (sig)	is a pointer to the byte(s) of the signature.
+ * (siglen)	number of bytes in the signature.
+ * (paralen)	signature paragraph (alignment) size.
+ * (sigofs)	offset of the signature within the paragraph.
+ *
+ * Returns the _physical_ address of the found signature, 0 if the
+ * signature was not found.
+ */
+
+u_int32_t
+bios_sigsearch(u_int32_t start, u_char *sig, int siglen, int paralen, int sigofs)
+{
+    u_char	*sp, *end;
+    int		i;
+    
+    /* compute the starting address */
+    if ((start >= BIOS_START) && (start <= (BIOS_START + BIOS_SIZE))) {
+	sp = (char *)BIOS_PADDRTOVADDR(start);
+    } else if (start == 0) {
+	sp = (char *)BIOS_PADDRTOVADDR(BIOS_START);
+    } else {
+	return 0;				/* bogus start address */
+    }
+
+    /* compute the end address */
+    end = (u_char *)BIOS_PADDRTOVADDR(BIOS_START + BIOS_SIZE);
+
+    /* loop searching */
+    while ((sp + sigofs + siglen) < end) {
+	
+	/* compare here */
+	if (!memcmp(sp + sigofs, sig, siglen)) {
+	    /* convert back to physical address */
+	    return((u_int32_t)BIOS_VADDRTOPADDR(sp));
+	}
+	sp += paralen;
+    }
+    return(0);
+}
+
+    
+	    
diff --git a/sys/i386/i386/bios.c b/sys/i386/i386/bios.c
new file mode 100644
index 0000000..256bb8b
--- /dev/null
+++ b/sys/i386/i386/bios.c
@@ -0,0 +1,231 @@
+/*-
+ * Copyright (c) 1997 Michael Smith
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *      $Id$
+ */
+
+/*
+ * Code for dealing with the BIOS in x86 PC systems.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <vm/vm.h>
+#include <vm/pmap.h>
+#include <machine/pmap.h>
+#include <machine/md_var.h>
+
+#include <machine/pc/bios.h>
+
+#define BIOS_START	0xe0000
+#define BIOS_SIZE	0x20000
+
+/* exported lookup results */
+struct bios32_SDentry	PCIbios = {entry : 0};
+struct SMBIOS_table	*SMBIOStable = 0;
+struct DMI_table	*DMItable = 0;
+
+static caddr_t		bios32_SDCI = NULL;
+
+static void		bios32_init(void *junk);
+
+/* start fairly early */
+SYSINIT(bios32, SI_SUB_CPU, SI_ORDER_ANY, bios32_init, NULL);
+
+/*
+ * bios32_init
+ *
+ * Locate various bios32 entities.
+ */
+static void
+bios32_init(void *junk)
+{
+    u_long			sigaddr;
+    struct bios32_SDheader	*sdh;
+    struct SMBIOS_table		*sbt;
+    struct DMI_table		*dmit;
+    u_int8_t			ck, *cv;
+    int				i;
+    
+
+    /*
+     * BIOS32 Service Directory
+     */
+    
+    /* look for the signature */
+    if ((sigaddr = bios_sigsearch(0, "_32_", 4, 16, 0)) != 0) {
+
+	/* get a virtual pointer to the structure */
+	sdh = (struct bios32_SDheader *)BIOS_PADDRTOVADDR(sigaddr);
+	for (cv = (u_int8_t *)sdh, ck = 0, i = 0; i < (sdh->len * 16); i++) {
+	    ck += cv[i];
+	}
+	/* If checksum is OK, enable use of the entrypoint */
+	if (ck == 0) {
+	    bios32_SDCI = (caddr_t)BIOS_PADDRTOVADDR(sdh->entry);
+	    if (bootverbose) {
+		printf("Found BIOS32 Service Directory header at %p\n", sdh);
+		printf("Entry = 0x%x (%p)  Rev = %d  Len = %d\n", 
+		       sdh->entry, bios32_SDCI, sdh->revision, sdh->len);
+	    }
+	    /* See if there's a PCI BIOS entrypoint here */
+	    PCIbios.ident.id = 0x49435024;	/* PCI systems should have this */
+	    if (!bios32_SDlookup(&PCIbios) && bootverbose)
+		printf("PCI BIOS entry at 0x%x\n", PCIbios.entry);
+	} else {
+	    printf("Bad BIOS32 Service Directory!\n");
+	}
+    }
+
+    /*
+     * System Management BIOS
+     */
+    /* look for the SMBIOS signature */
+    if ((sigaddr = bios_sigsearch(0, "_SM_", 4, 16, 0)) != 0) {
+
+	/* get a virtual pointer to the structure */
+	sbt = (struct SMBIOS_table *)BIOS_PADDRTOVADDR(sigaddr);
+	for (cv = (u_int8_t *)sbt, ck = 0, i = 0; i < sbt->len; i++) {
+	    ck += cv[i];
+	}
+	/* if checksum is OK, we have action */
+	if (ck == 0) {
+	    SMBIOStable = sbt;		/* save reference */
+	    DMItable = &sbt->dmi;	/* contained within */
+	    if (bootverbose) {
+		printf("SMIBIOS header at %p\n", sbt);
+		printf("Version %d.%d\n", sbt->major, sbt->minor);
+		printf("Table at 0x%x, %hd entries, %hd bytes, largest entry %hd bytes\n",
+		       dmit->st_base, dmit->st_entries, dmit->st_size, sbt->st_maxsize);
+	    }
+	} else {
+	    printf("Bad SMBIOS table checksum!\n");
+	}
+	
+    }
+    /* look for the DMI signature */
+    if ((sigaddr = bios_sigsearch(0, "_DMI_", 5, 16, 0)) != 0) {
+
+	/* get a virtual pointer to the structure */
+	dmit = (struct DMI_table *)BIOS_PADDRTOVADDR(sigaddr);
+	for (cv = (u_int8_t *)dmit, ck = 0, i = 0; i < 16; i++) {
+	    ck += cv[i];
+	}
+	/* if checksum is OK, we have action */
+	if (ck == 0) {
+	    DMItable = dmit;		/* save reference */
+	    if (bootverbose) {
+		printf("DMI header at %p\n", dmit);
+		printf("Version %x\n", dmit->bcd_revision);
+		printf("Table at 0x%x, %hd entries, %hd bytes\n",
+		       dmit->st_base, dmit->st_entries, dmit->st_size);
+	    }
+	} else {
+	    printf("Bad DMI table checksum!\n");
+	}
+    }
+
+}
+
+/*
+ * bios32_SDlookup
+ *
+ * Query the BIOS32 Service Directory for the service named in (ent),
+ * returns nonzero if the lookup fails.  The caller must fill in
+ * (ent->ident), the remainder are populated on a successful lookup.
+ */
+int
+bios32_SDlookup(struct bios32_SDentry *ent)
+{
+    struct bios32_args	args;
+    
+    if (bios32_SDCI != NULL) {
+
+	args.eax = ent->ident.id;		/* set up arguments */
+	args.ebx = args.ecx = args.edx = 0;
+	bios32(bios32_SDCI, &args);		/* make the BIOS call */
+	if ((args.eax & 0xff) == 0) {		/* success? */
+	    ent->base = args.ebx;
+	    ent->len = args.ecx;
+	    ent->entry = args.edx;
+	    return(0);				/* all OK */
+	}
+    }
+    return(1);					/* failed */
+}
+
+/*
+ * bios_sigsearch
+ *
+ * Search some or all of the BIOS region for a signature string.
+ *
+ * (start)	Optional offset returned from this function 
+ *		(for searching for multiple matches), or NULL
+ *		to start the search from the base of the BIOS.
+ *		Note that this will be a _physical_ address in
+ *		the range 0xe0000 - 0xfffff.
+ * (sig)	is a pointer to the byte(s) of the signature.
+ * (siglen)	number of bytes in the signature.
+ * (paralen)	signature paragraph (alignment) size.
+ * (sigofs)	offset of the signature within the paragraph.
+ *
+ * Returns the _physical_ address of the found signature, 0 if the
+ * signature was not found.
+ */
+
+u_int32_t
+bios_sigsearch(u_int32_t start, u_char *sig, int siglen, int paralen, int sigofs)
+{
+    u_char	*sp, *end;
+    int		i;
+    
+    /* compute the starting address */
+    if ((start >= BIOS_START) && (start <= (BIOS_START + BIOS_SIZE))) {
+	sp = (char *)BIOS_PADDRTOVADDR(start);
+    } else if (start == 0) {
+	sp = (char *)BIOS_PADDRTOVADDR(BIOS_START);
+    } else {
+	return 0;				/* bogus start address */
+    }
+
+    /* compute the end address */
+    end = (u_char *)BIOS_PADDRTOVADDR(BIOS_START + BIOS_SIZE);
+
+    /* loop searching */
+    while ((sp + sigofs + siglen) < end) {
+	
+	/* compare here */
+	if (!memcmp(sp + sigofs, sig, siglen)) {
+	    /* convert back to physical address */
+	    return((u_int32_t)BIOS_VADDRTOPADDR(sp));
+	}
+	sp += paralen;
+    }
+    return(0);
+}
+
+    
+	    
diff --git a/sys/i386/i386/bioscall.s b/sys/i386/i386/bioscall.s
new file mode 100644
index 0000000..a041e0b
--- /dev/null
+++ b/sys/i386/i386/bioscall.s
@@ -0,0 +1,59 @@
+/*-
+ * Copyright (c) 1997 Jonathan Lemon
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *      $Id$
+ */
+
+/*
+ * Functions for calling x86 BIOS functions from the BSD kernel
+ */
+	
+#include <machine/asmacros.h>
+
+	.text
+/*
+ * bios32(caddr_t func_addr, bios32_args *args)
+ */
+
+ENTRY(bios32)
+	pushl	%ebx
+	pushl	%esi
+	movl	(2*4+2*4)(%esp), %esi
+	movl	0(%esi), %eax
+	movl	4(%esi), %ebx
+	movl	8(%esi), %ecx
+	movl	12(%esi), %edx
+	movl	(2*4+1*4)(%esp), %esi
+	mov	%cs, %di
+	pushl	%edi				/* really lcall/lret */
+	call	%esi
+	movl	(2*4+2*4)(%esp), %esi
+	movl	%eax, 0(%esi)
+	movl	%ebx, 4(%esi)
+	movl	%ecx, 8(%esi)
+	movl	%edx, 12(%esi)
+	popl	%esi
+	popl	%ebx
+        ret