20060303

1 files changed, 189 insertions, 0 deletions

diff --git a/os/boot/rpcg/uartboot.c b/os/boot/rpcg/uartboot.c
new file mode 100644
index 00000000..0b11b5d5
--- /dev/null
+++ b/os/boot/rpcg/uartboot.c
@@ -0,0 +1,189 @@
+#include "boot.h"
+
+/*
+ * this doesn't yet use the crc
+ */
+
+typedef struct Uboot Uboot;
+struct Uboot {
+	Queue*	iq;
+	Block*	partial;
+	ulong	csum;
+	long	bno;
+	uchar	buf[64];
+	int	nleft;
+	int	ntimeout;
+};
+
+static	Uboot	uboot;
+ulong	crc32(void *buf, int n, ulong crc);
+
+static void
+uartbrecv(uchar *p, int n)
+{
+	Uboot *ub;
+	Block *b;
+
+	ub = &uboot;
+	if(n > 0 && ub->iq != nil){
+		b = iallocb(n);
+		memmove(b->wp, p, n);
+		b->wp += n;
+		qbwrite(ub->iq, b);
+	}
+}
+
+int
+uartinit(void)
+{
+	return 1<<0;
+}
+
+Partition*
+setuartpart(int, char *s)
+{
+	static Partition pp[1];
+
+	if(strcmp(s, "boot") != 0 && strcmp(s, "disk") != 0)
+		return 0;
+	pp[0].start = 0;
+	pp[0].end = 2*1024*1024;
+	strcpy(pp[0].name, "boot");
+	return pp;
+}
+
+long
+uartseek(int, long)
+{
+	/* start the boot */
+	if(uboot.iq == nil)
+		uboot.iq = qopen(64*1024, 0, 0, 0);
+	if(uboot.partial){
+		freeb(uboot.partial);
+		uboot.partial = 0;
+	}
+	print("uart: start transmission\n");
+	uartsetboot(uartbrecv);
+	uboot.csum = ~0;
+	uboot.bno = 0;
+	uboot.nleft = 0;
+	uboot.ntimeout = 0;
+	return 0;
+}
+
+static long
+uartreadn(void *buf, int nb)
+{
+	ulong start;
+	Uboot *ub;
+	int l;
+	Block *b;
+	uchar *p;
+
+	p = buf;
+	ub = &uboot;
+	start = m->ticks;
+	while(nb > 0){
+		b = ub->partial;
+		ub->partial = nil;
+		if(b == nil){
+			ub->ntimeout = 0;
+			while((b = qget(ub->iq)) == 0){
+				if(TK2MS(m->ticks - start) >= 15*1000){
+					if(++ub->ntimeout >= 3){
+						print("uart: timeout\n");
+						return 0;
+					}
+					uartputs("n", 1);
+				}
+			}
+		}
+		l = BLEN(b);
+		if(l > nb)
+			l = nb;
+		memmove(p, b->rp, l);
+		b->rp += l;
+		if(b->rp >= b->wp)
+			freeb(b);
+		else
+			ub->partial = b;
+		nb -= l;
+		p += l;
+	}
+	return p-(uchar*)buf;
+}
+
+long
+uartread(int, void *buf, long n)
+{
+	uchar *p;
+	int l;
+	static uchar lbuf[64];
+
+	p = buf;
+	if((l = uboot.nleft) > 0){
+		if(l > n)
+			l = n;
+		uboot.nleft -= l;
+		memmove(p, uboot.buf, l);
+		p += l;
+		n -= l;
+	}
+	while(n > 0){
+		l = uartreadn(lbuf, sizeof(lbuf));
+		if(l < sizeof(lbuf))
+			return 0;
+		if(l > n){
+			uboot.nleft = l-n;
+			memmove(uboot.buf, lbuf+n, uboot.nleft);
+			l = n;
+		}
+		memmove(p, lbuf, l);
+		n -= l;
+		p += l;
+		uboot.bno++;
+		uartputs("y", 1);
+	}
+	return p-(uchar*)buf;
+}
+
+/*
+ * from Rob Warnock
+ */
+static	ulong	crc32tab[256];	/* initialised on first call to crc32 */
+
+enum {
+	CRC32POLY = 0x04c11db7     /* AUTODIN II, Ethernet, & FDDI */
+};
+
+/*
+ * Build auxiliary table for parallel byte-at-a-time CRC-32.
+ */
+static void
+initcrc32(void)
+{
+	int i, j;
+	ulong c;
+
+	for(i = 0; i < 256; i++) {
+		for(c = i << 24, j = 8; j > 0; j--)
+			if(c & (1<<31))
+				c = (c<<1) ^ CRC32POLY;
+			else
+				c <<= 1;
+		crc32tab[i] = c;
+	}
+}
+
+ulong
+crc32(void *buf, int n, ulong crc)
+{
+	uchar *p;
+
+	if(crc32tab[1] == 0)
+		initcrc32();
+	crc = ~crc;
+	for(p = buf; --n >= 0;)
+		crc = (crc << 8) ^ crc32tab[(crc >> 24) ^ *p++];
+	return ~crc;
+}