core: use jiffies instead of BIOS_timer

Use jiffies instead of BIOS_timer.  In 16-bit code we can use the low
16 bits of __jiffies when appropriate, since we have proper 2's
complement wraparound at all times.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

6 files changed, 29 insertions, 32 deletions

diff --git a/core/fs/pxe/dnsresolv.c b/core/fs/pxe/dnsresolv.c
index 98bc960e..15560447 100644
--- a/core/fs/pxe/dnsresolv.c
+++ b/core/fs/pxe/dnsresolv.c
@@ -181,7 +181,7 @@ uint32_t dns_resolv(const char *name)
     int ques, reps;    /* number of questions and replies */
     uint8_t timeout;
     const uint8_t *timeout_ptr = TimeoutTable;
-    uint16_t oldtime;
+    uint32_t oldtime;
     uint32_t srv;
     uint32_t *srv_ptr = dns_server;
     struct dnshdr *hd1 = (struct dnshdr *)DNSSendBuf;
@@ -232,7 +232,7 @@ uint32_t dns_resolv(const char *name)
         if (err || udp_write.status != 0)
             continue;
         
-        oldtime = BIOS_timer;
+        oldtime = jiffies();
 	while (1) {
             udp_read.status      = 0;
             udp_read.src_ip      = srv;
@@ -249,7 +249,7 @@ uint32_t dns_resolv(const char *name)
             if (hd2->id == hd1->id)
                 break;
 
-	    if ((uint16_t)(BIOS_timer-oldtime) >= timeout) {
+	    if (jiffies()-oldtime >= timeout) {
 		/* time out */
 		timeout = *timeout_ptr++;
 		if (!timeout)
diff --git a/core/fs/pxe/pxe.c b/core/fs/pxe/pxe.c
index d7527177..4613e321 100644
--- a/core/fs/pxe/pxe.c
+++ b/core/fs/pxe/pxe.c
@@ -514,7 +514,7 @@ static void fill_buffer(struct open_file_t *file)
     const uint8_t *timeout_ptr = TimeoutTable;
     uint8_t timeout;
     uint16_t buffersize;
-    uint16_t old_time;
+    uint32_t oldtime;
     void *data = NULL;
     static __lowmem struct s_PXENV_UDP_READ udp_read;
         
@@ -538,7 +538,7 @@ static void fill_buffer(struct open_file_t *file)
     
     timeout_ptr = TimeoutTable;    
     timeout = *timeout_ptr++;
-    old_time = BIOS_timer;
+    oldtime = jiffies();
     while (timeout) {
         udp_read.buffer.offs = file->tftp_pktbuf;
         udp_read.buffer.seg  = PKTBUF_SEG;
@@ -549,13 +549,11 @@ static void fill_buffer(struct open_file_t *file)
         udp_read.d_port      = file->tftp_localport;
         err = pxe_call(PXENV_UDP_READ, &udp_read);
         if (err) {
-            if (BIOS_timer == old_time)
-                continue;
-            
-	    BIOS_timer = old_time;
-            timeout--;		/* decrease one timer tick */
-            if (!timeout) {
-                timeout = *timeout_ptr++;
+	    uint32_t now = jiffies();
+
+	    if (now-oldtime >= timeout) {
+		oldtime = now;
+		timeout = *timeout_ptr++;
 		if (!timeout)
 		    break;
 	    }
@@ -704,7 +702,7 @@ static void pxe_searchdir(char *filename, struct file *file)
     int buffersize;
     const uint8_t  *timeout_ptr;
     uint8_t  timeout;
-    uint16_t oldtime;
+    uint32_t oldtime;
     uint16_t tid;
     uint16_t opcode;
     uint16_t blk_num;
@@ -786,7 +784,7 @@ static void pxe_searchdir(char *filename, struct file *file)
     
     /* Packet transmitted OK, now we need to receive */
     timeout = *timeout_ptr++;
-    oldtime = BIOS_timer;
+    oldtime = jiffies();
     for (;;) {
         buf = packet_buf;
         udp_read.buffer.offs = OFFS_WRT(buf, 0);
@@ -796,13 +794,9 @@ static void pxe_searchdir(char *filename, struct file *file)
         udp_read.d_port = tid;
         err = pxe_call(PXENV_UDP_READ, &udp_read);
         if (err) {
-	    uint16_t now = BIOS_timer;
-            if (oldtime != now) {
-		oldtime = now;
-		timeout--;	/* Decrease one timer tick */
-		if (!timeout)
-		    goto failure;
-	    }
+	    uint32_t now = jiffies();
+	    if (now-oldtime >= timeout)
+		goto failure;
 	    continue;
         }
 
diff --git a/core/fs/pxe/pxe.h b/core/fs/pxe/pxe.h
index 8a2b190c..f62fa7a7 100644
--- a/core/fs/pxe/pxe.h
+++ b/core/fs/pxe/pxe.h
@@ -197,7 +197,6 @@ extern int have_uuid;
 extern uint8_t uuid_type;
 extern char uuid[];
 
-extern volatile uint16_t BIOS_timer;
 extern uint16_t BIOS_fbm;
 extern const uint8_t TimeoutTable[];
 
diff --git a/core/idle.inc b/core/idle.inc
index 966b6e26..8d699733 100644
--- a/core/idle.inc
+++ b/core/idle.inc
@@ -15,10 +15,10 @@
 TICKS_TO_IDLE	equ 4
 
 reset_idle:
-		push ax
-		mov ax,[cs:BIOS_timer]
-		mov [cs:IdleTimer],ax
-		pop ax
+		push eax
+		mov eax,[cs:__jiffies]
+		mov [cs:IdleTimer],eax
+		pop eax
 		sti		; Guard against BIOS/PXE brokenness...
 		ret
 
@@ -54,9 +54,9 @@ do_idle:
 		pop si
 		sti
 .ok:
-		mov ax,[BIOS_timer]
-		sub ax,[IdleTimer]
-		cmp ax,TICKS_TO_IDLE
+		mov eax,[__jiffies]
+		sub eax,[IdleTimer]
+		cmp eax,TICKS_TO_IDLE
 		jb .done
 		
 		mov eax,[idle_hook_func]
@@ -74,6 +74,7 @@ do_idle:
 .ret:		ret
 
 		section .data16
+		alignz 4
 		global idle_hook_func
 idle_hook_func	dd 0
 NoHalt		dw 0
@@ -81,4 +82,5 @@ NoHalt		dw 0
 hlt_err		db 'ERROR: idle with IF=0', CR, LF, 0 
 
 		section .bss16
-IdleTimer	resw 1
+		alignb 4
+IdleTimer	resd 1
diff --git a/core/pxelinux.asm b/core/pxelinux.asm
index 95aa58fb..995de327 100644
--- a/core/pxelinux.asm
+++ b/core/pxelinux.asm
@@ -243,6 +243,8 @@ local_boot:
 ; kaboom: write a message and bail out.  Wait for quite a while,
 ;	  or a user keypress, then do a hard reboot.
 ;
+;         Note: use BIOS_timer here; we may not have jiffies set up.
+;
                 global kaboom
 kaboom:
 		RESET_STACK_AND_SEGS AX
diff --git a/core/ui.inc b/core/ui.inc
index 87d0c647..9a653b1c 100644
--- a/core/ui.inc
+++ b/core/ui.inc
@@ -529,11 +529,11 @@ getchar_timeout:
 		call reset_idle
 
 .loop:
-		push word [BIOS_timer]
+		push word [__jiffies]
 		call pollchar
 		jnz .got_char
 		pop ax
-		cmp ax,[BIOS_timer]		; Has the timer advanced?
+		cmp ax,[__jiffies]		; Has the timer advanced?
 		je .loop
 
 		dec dword [ThisKbdTo]