I made a patch which lets the user specify the size of the DMA buffer
which should be used.
I coded a warning at a buffer usage of 80%.
Also, the default size was increased to 470k, I made a lot of tests
using different buffer widths and heights.
I found out that the max DMA buffer used was 2328 TS packets.
With this patch I got no dropouts at all when recording 6 streams with
VDR, making a backup between 2 disks and doing some random sync's.
I still have to disable the local APIC in bios though.
Regards,
Ingo Schneider.
diff -urw linux-2.6.14.5/drivers/media/dvb/ttpci/budget-core.c /usr/src/linux-2.6.15.2/drivers/media/dvb/ttpci/budget-core.c
--- linux-2.6.14.5/drivers/media/dvb/ttpci/budget-core.c 2005-12-27 01:26:33.000000000 +0100
+++ /usr/src/linux-2.6.15.2/drivers/media/dvb/ttpci/budget-core.c 2006-02-18 14:38:01.000000000 +0100
@@ -40,8 +40,11 @@
#include "ttpci-eeprom.h"
int budget_debug;
+int budget_buffer_size;
module_param_named(debug, budget_debug, int, 0644);
+module_param_named(bufsize, budget_buffer_size, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off budget debugging (default:off).");
+MODULE_PARM_DESC(bufsize, "DMA buffer size in kB (default: 470).");
/****************************************************************************
* TT budget / WinTV Nova
@@ -70,7 +73,7 @@
saa7146_write(dev, MC1, MASK_20); // DMA3 off
- memset(budget->grabbing, 0x00, TS_HEIGHT * TS_WIDTH);
+ memset(budget->grabbing, 0x00, TS_BUFLEN(budget));
saa7146_write(dev, PCI_BT_V1, 0x001c0000 | (saa7146_read(dev, PCI_BT_V1) & ~0x001f0000));
@@ -115,16 +118,11 @@
saa7146_write(dev, BASE_ODD3, 0);
saa7146_write(dev, BASE_EVEN3, 0);
- saa7146_write(dev, PROT_ADDR3, TS_WIDTH * TS_HEIGHT);
+ saa7146_write(dev, PROT_ADDR3, TS_BUFLEN(budget));
saa7146_write(dev, BASE_PAGE3, budget->pt.dma | ME1 | 0x90);
- if (budget->card->type == BUDGET_FS_ACTIVY) {
- saa7146_write(dev, PITCH3, TS_WIDTH / 2);
- saa7146_write(dev, NUM_LINE_BYTE3, ((TS_HEIGHT * 2) << 16) | (TS_WIDTH / 2));
- } else {
- saa7146_write(dev, PITCH3, TS_WIDTH);
- saa7146_write(dev, NUM_LINE_BYTE3, (TS_HEIGHT << 16) | TS_WIDTH);
- }
+ saa7146_write(dev, PITCH3, TS_WIDTH(budget));
+ saa7146_write(dev, NUM_LINE_BYTE3, (TS_HEIGHT(budget) << 16) | TS_WIDTH(budget));
saa7146_write(dev, MC2, (MASK_04 | MASK_20));
@@ -141,11 +139,12 @@
u8 *mem = (u8 *) (budget->grabbing);
u32 olddma = budget->ttbp;
u32 newdma = saa7146_read(budget->dev, PCI_VDP3);
+ int count = 0;
/* nearest lower position divisible by 188 */
newdma -= newdma % 188;
- if (newdma >= TS_BUFLEN)
+ if (newdma >= TS_BUFLEN(budget))
return;
budget->ttbp = newdma;
@@ -155,9 +154,15 @@
if (newdma > olddma) { /* no wraparound, dump olddma..newdma */
dvb_dmx_swfilter_packets(&budget->demux, mem + olddma, (newdma - olddma) / 188);
+ count = (newdma - olddma) / 188;
} else { /* wraparound, dump olddma..buflen and 0..newdma */
- dvb_dmx_swfilter_packets(&budget->demux, mem + olddma, (TS_BUFLEN - olddma) / 188);
+ dvb_dmx_swfilter_packets(&budget->demux, mem + olddma, (TS_BUFLEN(budget) - olddma) / 188);
dvb_dmx_swfilter_packets(&budget->demux, mem, newdma / 188);
+ count = (TS_BUFLEN(budget) - olddma) / 188 + newdma / 188;
+ }
+
+ if (count > (TS_MAX_PACKETS(budget) * 80/100)) {
+ printk("ttpci vpeirq: warning: using more than 80 percent of buffer for %d packets\n", count);
}
}
@@ -341,7 +346,6 @@
struct saa7146_pci_extension_data *info,
struct module *owner)
{
- int length = TS_WIDTH * TS_HEIGHT;
int ret = 0;
struct budget_info *bi = info->ext_priv;
@@ -352,6 +356,25 @@
budget->card = bi;
budget->dev = (struct saa7146_dev *) dev;
+ if (budget->card->type == BUDGET_FS_ACTIVY) {
+ budget->buffer_width = TS_DEFAULT_WIDTH/2;
+ budget->buffer_height = TS_DEFAULT_HEIGHT*2;
+ } else {
+ budget->buffer_width = TS_DEFAULT_WIDTH;
+ budget->buffer_height = TS_DEFAULT_HEIGHT;
+ }
+
+ if (budget_buffer_size >= TS_MIN_BUFSIZE_K && budget_buffer_size <= TS_MAX_BUFSIZE_K) {
+ int bufsize = budget_buffer_size * 1024;
+
+ if (bufsize / budget->buffer_width > TS_MAX_HEIGHT && budget->card->type != BUDGET_FS_ACTIVY) // keep width constant as long if possible
+ budget->buffer_width = BUDGET_MOD_LIMIT(bufsize/TS_MAX_HEIGHT, TS_MOD_WIDTH, TS_MAX_WIDTH);
+
+ budget->buffer_height = BUDGET_MOD_LIMIT(bufsize/budget->buffer_width, TS_MOD_HEIGHT, TS_MAX_HEIGHT);
+ }
+
+ printk("budget: width = %d, height = %d\n", budget->buffer_width, budget->buffer_height);
+
dvb_register_adapter(&budget->dvb_adapter, budget->card->name, owner);
/* set dd1 stream a & b */
@@ -392,7 +415,7 @@
ttpci_eeprom_parse_mac(&budget->i2c_adap, budget->dvb_adapter.proposed_mac);
if (NULL ==
- (budget->grabbing = saa7146_vmalloc_build_pgtable(dev->pci, length, &budget->pt))) {
+ (budget->grabbing = saa7146_vmalloc_build_pgtable(dev->pci, TS_BUFLEN(budget), &budget->pt))) {
ret = -ENOMEM;
goto err;
}
@@ -476,5 +499,6 @@
EXPORT_SYMBOL_GPL(ttpci_budget_irq10_handler);
EXPORT_SYMBOL_GPL(ttpci_budget_set_video_port);
EXPORT_SYMBOL_GPL(budget_debug);
+EXPORT_SYMBOL_GPL(budget_buffer_size);
MODULE_LICENSE("GPL");
diff -urw linux-2.6.14.5/drivers/media/dvb/ttpci/budget.h /usr/src/linux-2.6.15.2/drivers/media/dvb/ttpci/budget.h
--- linux-2.6.14.5/drivers/media/dvb/ttpci/budget.h 2005-12-27 01:26:33.000000000 +0100
+++ /usr/src/linux-2.6.15.2/drivers/media/dvb/ttpci/budget.h 2006-02-18 14:45:28.000000000 +0100
@@ -13,6 +13,7 @@
#include <media/saa7146.h>
extern int budget_debug;
+extern int budget_buffer_size;
#ifdef dprintk
#undef dprintk
@@ -55,6 +56,8 @@
int ci_present;
int video_port;
+ int buffer_width;
+ int buffer_height;
u8 tsf;
u32 ttbp;
@@ -77,10 +80,22 @@
.ext_priv = &x_var ## _info, \
.ext = &budget_extension };
-#define TS_WIDTH (376)
-#define TS_HEIGHT (512)
-#define TS_BUFLEN (TS_WIDTH*TS_HEIGHT)
-#define TS_MAX_PACKETS (TS_BUFLEN/TS_SIZE)
+#define TS_WIDTH(budget) (budget->buffer_width)
+#define TS_HEIGHT(budget) (budget->buffer_height)
+#define TS_BUFLEN(budget) (budget->buffer_width * budget->buffer_height)
+#define TS_MAX_PACKETS(budget) (TS_BUFLEN(budget)/TS_SIZE)
+
+#define TS_DEFAULT_WIDTH 376
+#define TS_DEFAULT_HEIGHT 1280 // 1024 was tested to be not enough
+#define TS_MOD_WIDTH 376 // 2 * TS_SIZE (% 8 == 0)
+#define TS_MOD_HEIGHT 256 // 0x0100
+#define TS_MAX_WIDTH 3760 // 10 * (2*TS_SIZE)
+#define TS_MAX_HEIGHT 3840 // 0x0f00
+
+#define TS_MIN_BUFSIZE_K 188
+#define TS_MAX_BUFSIZE_K 4096 // spec says SAA7146 can handle at most 4 MB DMA and this is known to work
+
+#define BUDGET_MOD_LIMIT(value,mod,limit) ((value) > (limit) ? ((limit) - (limit) % (mod)) : ((value) - (value) % (mod)))
#define BUDGET_TT 0
#define BUDGET_TT_HW_DISEQC 1
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