[Linux1394-cvslog] rev 690 - trunk

[SVN U. <dde...@li...>]

Author: ddennedy
Date: 2002-11-18 02:22:43 -0500 (Mon, 18 Nov 2002)
New Revision: 690

Modified:
   trunk/dv1394.c
Log:
improved reception overrun handling between DMA, packet buffer, and frame buffer

Modified: trunk/dv1394.c
==============================================================================
--- trunk/dv1394.c	(original)
+++ trunk/dv1394.c	2002-11-18 02:22:44.000000000 -0500
@@ -53,6 +53,8 @@
     via pci_alloc_consistent()
     
   DONE:
+  - during reception, better handling of dropped frames and continuity errors
+  - during reception, prevent DMA from bypassing the irq tasklets
   - reduce irq rate during reception (1/250 packets).
   - add many more internal buffers during reception with scatter/gather dma.
   - add dbc (continuity) checking on receive, increment status.dropped_frames
@@ -760,6 +762,9 @@
 	int dif_sequence = p->data[1] >> 4;           /* dif sequence number is in bits 4 - 7 */
 	int dif_block = p->data[2];
 
+	/* sanity check */
+	if (dif_sequence > 11 || dif_block > 149) return;
+		
 	switch (section_type) {
 	case 0:           /* 1 Header block */
 	        memcpy( (void *) f->data + dif_sequence * 150 * 80, p->data, 480);
@@ -898,10 +903,6 @@
 	
 	} /* next j */
 
-	/* loop tail to head */
-	if (f != NULL && f->frame_end_branch != NULL)
-		*(f->frame_end_branch) = cpu_to_le32(video->frames[0]->descriptor_pool_dma | 1); /* set Z=1 */
-
 	spin_unlock_irqrestore(&video->spinlock, irq_flags);
 
 }
@@ -1142,7 +1143,7 @@
 	struct dv1394_init init;
 
 	init.api_version = DV1394_API_VERSION;
-	init.n_frames = 2;
+	init.n_frames = DV1394_MAX_FRAMES / 4;
 	/* the following are now set via proc_fs or devfs */
 	init.channel = video->channel;
 	init.format = video->pal_or_ntsc;
@@ -2292,8 +2293,9 @@
 
 	spin_lock(&video->spinlock);
 
-	if( (video->ohci_ir_ctx != -1) &&
-	    (reg_read(video->ohci, video->ohci_IsoRcvContextControlSet) & (1 << 10)) ) { 
+	if( (video->ohci_ir_ctx != -1) 
+	    && (reg_read(video->ohci, video->ohci_IsoRcvContextControlSet) & (1 << 10)) ) 
+	{ 
 
 		int sof=0; /* start-of-frame flag */
 		struct frame *f;
@@ -2301,7 +2303,12 @@
 		int i, dbc=0;
 		struct DMA_descriptor_block *block = NULL;
 		u16 xferstatus;
-		
+
+		int next_i, prev_i;
+		struct DMA_descriptor_block *next = NULL;
+		dma_addr_t next_dma = 0;
+		struct DMA_descriptor_block *prev = NULL;
+
 		/* loop over all descriptors in all frames */
 		for (i = 0; i < video->n_frames*MAX_PACKETS; i++) {
 			struct packet *p = dma_region_i(&video->packet_buf, struct packet, video->current_packet);
@@ -2338,7 +2345,12 @@
 	
 				dbc = (int) (p->cip_h1 >> 24);
 				if ( video->continuity_counter != -1 && dbc > ((video->continuity_counter + 1) % 256) )
-					video->dropped_frames++;
+				{
+					video->dropped_frames += video->n_clear_frames + 1;
+					video->first_frame = 0;
+					video->n_clear_frames = 0;
+					video->first_clear_frame = -1;
+				}
 				video->continuity_counter = dbc;
 				
 				if (!video->first_frame) {
@@ -2351,8 +2363,11 @@
 					frame_reset(f);  /* f->state = STATE_CLEAR */
 					video->n_clear_frames++;
 					if (video->n_clear_frames > video->n_frames) {
-						video->n_clear_frames = video->n_frames;
 						video->dropped_frames++;
+						video->n_clear_frames--;
+						if (video->n_clear_frames < 0)
+							video->n_clear_frames = 0;
+						video->first_clear_frame = (video->first_clear_frame + 1) % video->n_frames;
 					}
 					if (video->first_clear_frame == -1)
 						video->first_clear_frame = video->active_frame;
@@ -2388,6 +2403,29 @@
 			/* reset xferStatus & resCount */
 			block->u.in.il.q[3] = cpu_to_le32(512);
 
+			/* terminate dma chain at this (next) packet */
+			next_i = video->current_packet;
+			f = video->frames[next_i / MAX_PACKETS];
+			next = &(f->descriptor_pool[next_i % MAX_PACKETS]);
+			next_dma = ((unsigned long) block - (unsigned long) f->descriptor_pool) + f->descriptor_pool_dma;
+			next->u.in.il.q[0] |= 3 << 20; /* enable interrupt */
+			next->u.in.il.q[2] = 0; /* disable branch */
+			
+			/* link previous to next */
+			prev_i = (next_i == 0) ? (MAX_PACKETS * video->n_frames - 1) : (next_i - 1);
+			f = video->frames[prev_i / MAX_PACKETS];
+			prev = &(f->descriptor_pool[prev_i % MAX_PACKETS]);
+			if(prev_i % (MAX_PACKETS/2)) {
+				prev->u.in.il.q[0] &= ~(3 << 20); /* no interrupt */
+			} else {
+				prev->u.in.il.q[0] |= 3 << 20; /* enable interrupt */
+			}
+			prev->u.in.il.q[2] =  (cpu_to_le32(next_dma) | 1); /* set Z=1 */
+			wmb();
+
+			/* wake up DMA in case it fell asleep */
+			reg_write(video->ohci, video->ohci_IsoRcvContextControlSet, (1 << 12));
+
 			/* advance packet_buffer cursor */
 			video->current_packet = (video->current_packet + 1) % (MAX_PACKETS * video->n_frames);
 			
@@ -2396,7 +2434,7 @@
 		wake = 1; /* why the hell not? */
 		
 	} /* receive interrupt */
-
+	
 	spin_unlock(&video->spinlock);
 	
 	if(wake) {