PnP BIOS enumerator; mostly useful for hunting PnP devices that are supported

by the system BIOS rather than supporting ISA PnP.

1 files changed, 290 insertions, 0 deletions

diff --git a/sys/boot/i386/libi386/biospnp.c b/sys/boot/i386/libi386/biospnp.c
new file mode 100644
index 0000000..2cf5fb4
--- /dev/null
+++ b/sys/boot/i386/libi386/biospnp.c
@@ -0,0 +1,290 @@
+/*-
+ * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
+ * 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.
+ *
+ *	$Id$
+ */
+
+/*
+ * PnP BIOS enumerator, uses ISA PnP enumerator for fallback.
+ */
+
+#include <stand.h>
+#include <string.h>
+#include <machine/stdarg.h>
+#include <bootstrap.h>
+#include <isapnp.h>
+#include <btxv86.h>
+
+
+static int	biospnp_init(void);
+static void	biospnp_enumerate(void);
+
+struct pnphandler biospnphandler =
+{
+    "PnP BIOS",
+    biospnp_enumerate
+};
+
+struct pnp_ICstructure
+{
+    u_int8_t	pnp_signature[4]	 __attribute__ ((packed));
+    u_int8_t	pnp_version		 __attribute__ ((packed));
+    u_int8_t	pnp_length		 __attribute__ ((packed));
+    u_int16_t	pnp_BIOScontrol		 __attribute__ ((packed));
+    u_int8_t	pnp_checksum		 __attribute__ ((packed));
+    u_int32_t	pnp_eventflag		 __attribute__ ((packed));
+    u_int16_t	pnp_rmip		 __attribute__ ((packed));
+    u_int16_t	pnp_rmcs		 __attribute__ ((packed));
+    u_int16_t	pnp_pmip		 __attribute__ ((packed));
+    u_int32_t	pnp_pmcs		 __attribute__ ((packed));
+    u_int8_t	pnp_OEMdev[4]		 __attribute__ ((packed));
+    u_int16_t	pnp_rmds		 __attribute__ ((packed));
+    u_int32_t	pnp_pmds		 __attribute__ ((packed));
+};
+
+struct pnp_devNode 
+{
+    u_int16_t	dn_size		__attribute__ ((packed));
+    u_int8_t	dn_handle	__attribute__ ((packed));
+    u_int8_t	dn_id[4]	__attribute__ ((packed));
+    u_int8_t	dn_type[3]	__attribute__ ((packed));
+    u_int16_t	dn_attrib	__attribute__ ((packed));
+    u_int8_t	dn_data[0]	__attribute__ ((packed));
+};
+
+struct pnp_isaConfiguration
+{
+    u_int8_t	ic_revision	__attribute__ ((packed));
+    u_int8_t	ic_nCSN		__attribute__ ((packed));
+    u_int16_t	ic_rdport	__attribute__ ((packed));
+    u_int16_t	ic_reserved	__attribute__ ((packed));
+};
+
+static struct pnp_ICstructure	*pnp_Icheck = NULL;
+static u_int16_t		pnp_NumNodes;
+static u_int16_t		pnp_NodeSize;
+
+static void	biospnp_scanresdata(struct pnpinfo *pi, struct pnp_devNode *dn);
+static int	biospnp_call(int func, char *fmt, ...);
+
+#define vsegofs(vptr)	(((u_int32_t)VTOPSEG(vptr) << 16) + VTOPOFF(vptr))
+void	(* v86bios)(u_int32_t arg0, u_int32_t arg1, u_int32_t arg2, u_int32_t arg3) = (void *)v86int;
+
+#define	biospnp_f00(NumNodes, NodeSize)			biospnp_call(0x00, "ll", NumNodes, NodeSize)
+#define biospnp_f01(Node, devNodeBuffer, Control)	biospnp_call(0x01, "llw", Node, devNodeBuffer, Control)
+#define biospnp_f40(Configuration)			biospnp_call(0x40, "l", Configuration)
+
+/* PnP BIOS return codes */
+#define PNP_SUCCESS			0x00
+#define PNP_FUNCTION_NOT_SUPPORTED	0x80
+
+/*
+ * Initialisation: locate the PnP BIOS, test that we can call it.
+ * Returns nonzero if the PnP BIOS is not usable on this system.
+ */
+static int
+biospnp_init(void)
+{
+    struct pnp_isaConfiguration	icfg;
+    char			*sigptr;
+    int				result;
+    
+    /* Search for the $PnP signature */
+    pnp_Icheck = NULL;
+    for (sigptr = PTOV(0xf0000); sigptr < PTOV(0xfffff); sigptr += 16)
+	if (!bcmp(sigptr, "$PnP", 4)) {
+	    pnp_Icheck = (struct pnp_ICstructure *)sigptr;
+	    break;
+	}
+	
+    /* No signature, no BIOS */
+    if (pnp_Icheck == NULL)
+	return(1);
+
+    /*
+     * Fetch the system table parameters as a test of the BIOS
+     */
+    result = biospnp_f00(vsegofs(&pnp_NumNodes), vsegofs(&pnp_NodeSize));
+    if (result != PNP_SUCCESS) {
+	return(1);
+    }
+
+    /*
+     * Look for the PnP ISA configuration table 
+     */
+    result = biospnp_f40(vsegofs(&icfg));
+    switch (result) {
+    case PNP_SUCCESS:
+	/* If the BIOS found some PnP devices, take its hint for the read port */
+	if ((icfg.ic_revision == 1) && (icfg.ic_nCSN > 0))
+	    isapnp_readport = icfg.ic_rdport;
+	break;
+    case PNP_FUNCTION_NOT_SUPPORTED:
+	/* The BIOS says there is no ISA bus (should we trust that this works?) */
+	printf("PnP BIOS claims no ISA bus\n");
+	isapnp_readport = -1;
+	break;
+    }
+    return(0);
+}
+
+static void
+biospnp_enumerate(void)
+{
+    u_int8_t		Node;
+    struct pnp_devNode	*devNodeBuffer;
+    int			result;
+    struct pnpinfo	*pi;
+    int			count;
+
+    /* Init/check state */
+    if (biospnp_init())
+	return;
+
+    devNodeBuffer = (struct pnp_devNode *)malloc(pnp_NodeSize);
+    Node = 0;
+    count = 1000;
+    while((Node != 0xff) && (count-- > 0)) {
+	result = biospnp_f01(vsegofs(&Node), vsegofs(devNodeBuffer), 0x1);
+	if (result != PNP_SUCCESS) {
+	    printf("PnP BIOS node %d: error 0x%x\n", Node, result);
+	} else {
+	    pi = pnp_allocinfo();
+	    pnp_addident(pi, pnp_eisaformat(devNodeBuffer->dn_id));
+	    biospnp_scanresdata(pi, devNodeBuffer);
+	    pnp_addinfo(pi);
+	}
+    }
+}
+#define   offsetof(type, member)  ((size_t)(&((type *)0)->member))
+
+/*
+ * Scan the resource data in the node's data area for compatible device IDs
+ * and descriptions.
+ */
+static void
+biospnp_scanresdata(struct pnpinfo *pi, struct pnp_devNode *dn)
+{
+    int		tag, i, rlen, dlen;
+    u_int8_t	*p;
+    char	*str;
+
+    p = dn->dn_data;			/* point to resource data */
+    dlen = dn->dn_size - (p - (u_int8_t *)dn);	/* length of resource data */
+
+    for (i = 0; i < dlen; i+= rlen) {
+	tag = p[i];
+	i++;
+	if (PNP_RES_TYPE(tag) == 0) {
+	    rlen = PNP_SRES_LEN(tag);
+	    /* small resource */
+	    switch (PNP_SRES_NUM(tag)) {
+
+	    case COMP_DEVICE_ID:
+		/* got a compatible device ID */
+		pnp_addident(pi, pnp_eisaformat(p + i));
+		break;
+		
+	    case END_TAG:
+		return;
+	    }
+	} else {
+	    /* large resource */
+	    rlen = *(u_int16_t *)(p + i);
+	    i += sizeof(u_int16_t);
+	    
+	    switch(PNP_LRES_NUM(tag)) {
+
+	    case ID_STRING_ANSI:
+		str = malloc(rlen + 1);
+		bcopy(p + i, str, rlen);
+		str[rlen] = 0;
+		if (pi->pi_desc == NULL) {
+		    pi->pi_desc = str;
+		} else {
+		    free(str);
+		}
+		break;
+	    }
+	}
+    }
+}
+
+
+/*
+ * Make a 16-bit realmode PnP BIOS call.
+ *
+ * The first argument passed is the function number, the last is the
+ * BIOS data segment selector.  Intermediate arguments may be 16 or 
+ * 32 bytes in length, and are described by the format string.
+ *
+ * Arguments to the BIOS functions must be packed on the stack, hence
+ * this evil.
+ */
+static int
+biospnp_call(int func, char *fmt, ...)
+{
+    va_list	ap;
+    char	*p;
+    u_int8_t	*argp;
+    u_int32_t	args[4];
+    u_int32_t	i;
+
+    /* function number first */
+    argp = (u_int8_t *)args;
+    *(u_int16_t *)argp = func;
+    argp += sizeof(u_int16_t);
+
+    /* take args according to format */
+    va_start(ap, fmt);
+    for (p = fmt; *p != 0; p++) {
+	switch(*p) {
+
+	case 'w':
+	    i = va_arg(ap, u_int16_t);
+	    *(u_int16_t *)argp = i;
+	    argp += sizeof(u_int16_t);
+	    break;
+	    
+	case 'l':
+	    i = va_arg(ap, u_int32_t);
+	    *(u_int32_t *)argp = i;
+	    argp += sizeof(u_int32_t);
+	    break;
+	}
+    }
+
+    /* BIOS segment last */
+    *(u_int16_t *)argp = pnp_Icheck->pnp_rmds;
+    argp += sizeof(u_int16_t);
+
+    /* prepare for call */
+    v86.ctl = V86_ADDR | V86_CALLF; 
+    v86.addr = ((u_int32_t)pnp_Icheck->pnp_rmcs << 16) + pnp_Icheck->pnp_rmip;
+    
+    /* call with packed stack and return */
+    v86bios(args[0], args[1], args[2], args[3]);
+    return(v86.eax & 0xffff);
+}