git: 9front

--- a/sys/src/9/pc/archacpi.c

+++ b/sys/src/9/pc/archacpi.c

@@ -79,55 +79,7 @@

 	return get32(t->len) - sizeof(Tbl);

-static int

-checksum(void *v, int n)

-{

-	uchar *p, s;

-	s = 0;

-	p = v;

-	while(n-- > 0)

-		s += *p++;

-	return s;

-}

-static void*

-rsdscan(uchar* addr, int len, char* sig)

-{

-	int sl;

-	uchar *e, *p;

-	e = addr+len;

-	sl = strlen(sig);

-	for(p = addr; p+sl < e; p += 16){

-		if(memcmp(p, sig, sl))

-			continue;

-		return p;

-	}

-	return nil;

-}

-static void*

-rsdsearch(char* sig)

-{

-	uintptr p;

-	uchar *bda;

-	Rsd *rsd;

-	/*

-	 * Search for the data structure signature:

-	 * 1. in the first KB of the EBDA;

-	 * 2. in the BIOS ROM between 0xE0000 and 0xFFFFF.

-	 */

-	if(strncmp((char*)KADDR(0xFFFD9), "EISA", 4) == 0){

-		bda = KADDR(0x400);

-		if((p = (bda[0x0F]<<8)|bda[0x0E]))

-			if(rsd = rsdscan(KADDR(p), 1024, sig))

-				return rsd;

-	}

-	return rsdscan(KADDR(0xE0000), 0x20000, sig);

-}

 static Tbl*

 findtable(void *sig){

 	int i;

@@ -538,7 +490,9 @@

 	if((cp = getconf("*acpi")) == nil)

 		return 1;

-	if((rsd = rsdsearch("RSD PTR ")) == nil)

+	if((rsd = sigsearch("RSD PTR ")) == nil)

+		return 1;

+	if(checksum(rsd, 20) && checksum(rsd, 36))

 		return 1;

 	addarchfile("acpitbls", 0444, readtbls, nil);

 	if(strcmp(cp, "0") == 0)

--- a/sys/src/9/pc/archmp.c

+++ b/sys/src/9/pc/archmp.c

@@ -354,51 +354,6 @@

 	mpinit();

-static _MP_*

-mpscan(uchar *addr, int len)

-{

-	uchar *e, *p, sum;

-	int i;

-	e = addr+len;

-	for(p = addr; p < e; p += sizeof(_MP_)){

-		if(memcmp(p, "_MP_", 4))

-			continue;

-		sum = 0;

-		for(i = 0; i < sizeof(_MP_); i++)

-			sum += p[i];

-		if(sum == 0)

-			return (_MP_*)p;

-	}

-	return 0;

-}

-static _MP_*

-mpsearch(void)

-{

-	uchar *bda;

-	ulong p;

-	_MP_ *mp;

-	/*

-	 * Search for the MP Floating Pointer Structure:

-	 * 1) in the first KB of the EBDA;

-	 * 2) in the last KB of system base memory;

-	 * 3) in the BIOS ROM between 0xE0000 and 0xFFFFF.

-	 */

-	bda = KADDR(0x400);

-	if((p = (bda[0x0F]<<8)|bda[0x0E])){

-		if(mp = mpscan(KADDR(p<<4), 1024))

-			return mp;

-	}

-	else{

-		p = ((bda[0x14]<<8)|bda[0x13])*1024;

-		if(mp = mpscan(KADDR(p-1024), 1024))

-			return mp;

-	}

-	return mpscan(KADDR(0xF0000), 0x10000);

-}

 static int identify(void);

 PCArch archmp = {

@@ -418,8 +373,6 @@

 	char *cp;

 	_MP_ *_mp_;

-	uchar *p, sum;

-	ulong length;

 	if((cp = getconf("*nomp")) != nil && strcmp(cp, "0") != 0)

 		return 1;

@@ -431,21 +384,12 @@

 	 * if correct, check the version.

 	 * To do: check extended table checksum.

*/

-	if((_mp_ = mpsearch()) == 0 || _mp_->physaddr == 0)

+	if((_mp_ = sigsearch("_MP_")) == 0 || _mp_->physaddr == 0)

 		return 1;

 	pcmp = KADDR(_mp_->physaddr);

-	if(memcmp(pcmp, "PCMP", 4)){

-		pcmp = nil;

-		return 1;

-	}

-	length = pcmp->length;

-	sum = 0;

-	for(p = (uchar*)pcmp; length; length--)

-		sum += *p++;

-	if(sum || (pcmp->version != 1 && pcmp->version != 4)){

+	if(memcmp(pcmp, "PCMP", 4) || checksum(pcmp, pcmp->length) ||

+	   (pcmp->version != 1 && pcmp->version != 4)) {

 		pcmp = nil;

 		return 1;

--- a/sys/src/9/pc/bios32.c

+++ b/sys/src/9/pc/bios32.c

@@ -7,7 +7,6 @@

 #define VFLAG(...)	if(vflag) print(__VA_ARGS__)

-#define BIOSSEG(a)	KADDR(((uint)(a))<<4)

 #define UPTR2INT(p)	((uintptr)(p))

 #define l16get(p)	(((p)[1]<<8)|(p)[0])

@@ -48,37 +47,6 @@

 	return r;

-static void*

-rsdchecksum(void* addr, int length)

-{

-	u8int *p, sum;

-	sum = 0;

-	for(p = addr; length-- > 0; p++)

-		sum += *p;

-	if(sum == 0)

-		return addr;

-	return nil;

-}

-static void*

-rsdscan(u8int* addr, int len, char* signature)

-{

-	int sl;

-	u8int *e, *p;

-	e = addr+len;

-	sl = strlen(signature);

-	for(p = addr; p+sl < e; p += 16){

-		if(memcmp(p, signature, sl))

-			continue;

-		return p;

-	}

-	return nil;

-}

 static int

 bios32locate(void)

@@ -86,9 +54,9 @@

 	BIOS32sdh *sdh;

 	VFLAG("bios32link\n");

-	if((sdh = rsdscan(BIOSSEG(0xE000), 0x20000, "_32_")) == nil)

+	if((sdh = sigsearch("_32_")) == nil)

 		return -1;

-	if(rsdchecksum(sdh, sizeof(BIOS32sdh)) == nil)

+	if(checksum(sdh, sizeof(BIOS32sdh)))

 		return -1;

 	VFLAG("sdh @ %#p, entry %#ux\n", sdh, l32get(sdh->physaddr));

--- a/sys/src/9/pc/fns.h

+++ b/sys/src/9/pc/fns.h

@@ -9,6 +9,7 @@

 BIOS32si* bios32open(char*);

 void	bootargs(void*);

 ulong	cankaddr(ulong);

+int	checksum(void *, int);

 void	clockintr(Ureg*, void*);

 int	(*cmpswap)(long*, long, long);

 int	cmpswap486(long*, long, long);

@@ -157,6 +158,7 @@

 void	realmode(Ureg*);

 void	screeninit(void);

 void	(*screenputs)(char*, int);

+void*	sigsearch(char*);

 void	syncclock(void);

 void	syscallfmt(int syscallno, ulong pc, va_list list);

 void	sysretfmt(int syscallno, va_list list, long ret, uvlong start, uvlong stop);

--- a/sys/src/9/pc/memory.c

+++ b/sys/src/9/pc/memory.c

@@ -313,6 +313,66 @@

 	umbexclude();

+int

+checksum(void *v, int n)

+{

+	uchar *p, s;

+	s = 0;

+	p = v;

+	while(n-- > 0)

+		s += *p++;

+	return s;

+}

+static void*

+sigscan(uchar* addr, int len, char* signature)

+{

+	int sl;

+	uchar *e, *p;

+	e = addr+len;

+	sl = strlen(signature);

+	for(p = addr; p+sl < e; p += 16)

+		if(memcmp(p, signature, sl) == 0)

+			return p;

+	return nil;

+}

+void*

+sigsearch(char* signature)

+{

+	uintptr p;

+	uchar *bda;

+	void *r;

+	/*

+	 * Search for the data structure:

+	 * 1) within the first KiB of the Extended BIOS Data Area (EBDA), or

+	 * 2) within the last KiB of system base memory if the EBDA segment

+	 *    is undefined, or

+	 * 3) within the BIOS ROM address space between 0xf0000 and 0xfffff

+	 *    (but will actually check 0xe0000 to 0xfffff).

+	 */

+	bda = KADDR(0x400);

+	if(memcmp(KADDR(0xfffd9), "EISA", 4) == 0){

+		if((p = (bda[0x0f]<<8)|bda[0x0e]) != 0){

+			if((r = sigscan(KADDR(p<<4), 1024, signature)) != nil)

+				return r;

+		}

+	}

+	if((p = ((bda[0x14]<<8)|bda[0x13])*1024) != 0){

+		if((r = sigscan(KADDR(p-1024), 1024, signature)) != nil)

+			return r;

+	}

+	/* hack for virtualbox: look in KiB below 0xa0000 */

+	if((r = sigscan(KADDR(0xa0000-1024), 1024, signature)) != nil)

+		return r;

+	return sigscan(KADDR(0xe0000), 0x20000, signature);

+}

 static void

 lowraminit(void)

--- a/sys/src/9/pc/pci.c

+++ b/sys/src/9/pc/pci.c

@@ -739,19 +739,17 @@

 	Pcidev *sbpci, *pci;

 	uchar *p, pin, irq, link, *map;

-	/* Search for PCI interrupt routing table in BIOS */

-	for(p = (uchar *)KADDR(0xf0000); p < (uchar *)KADDR(0xfffff); p += 16)

-		if(p[0] == '$' && p[1] == 'P' && p[2] == 'I' && p[3] == 'R')

-			break;

+	if((p = sigsearch("$PIR")) == 0)

+		return;

-	if(p >= (uchar *)KADDR(0xfffff))

+	r = (Router*)p;

+	size = (r->size[1] << 8)|r->size[0];

+	if(size < sizeof(Router) || checksum(r, size))

 		return;

-	r = (Router *)p;

+	if(0) print("PCI interrupt routing table version %d.%d at %p\n",

+		r->version[0], r->version[1], r);

-	// print("PCI interrupt routing table version %d.%d at %.6uX\n",

-	//	r->version[0], r->version[1], (ulong)r & 0xfffff);

 	tbdf = (BusPCI << 24)|(r->bus << 16)|(r->devfn << 8);

 	sbpci = pcimatchtbdf(tbdf);

 	if(sbpci == nil) {

@@ -772,8 +770,6 @@

 		return;

 	pciirqs = (r->pciirqs[1] << 8)|r->pciirqs[0];

-	size = (r->size[1] << 8)|r->size[0];

 	for(e = (Slot *)&r[1]; (uchar *)e < p + size; e++) {

 		if (0) {

 			print("%.2uX/%.2uX %.2uX: ", e->bus, e->dev, e->slot);

--

⑨