improve performance by using threads

diff --git a/jtagkey.c b/jtagkey.c
index 41f0fd60723df3d2e472ada46b1a2cd8da1d0690..e17afc8895a71aa55da0bd7bb6bcd5c091a848f0 100644 (file)
--- a/jtagkey.c
+++ b/jtagkey.c
@@ -1,15 +1,15 @@
 #include <stdio.h>
 #include <ftdi.h>
 #include <unistd.h>
+#include <pthread.h>
 #include "usb-driver.h"
 #include "config.h"
 #include "jtagkey.h"
 
-#define USBBUFSIZE 4096
+#define USBBUFSIZE 1048576
 #define SLOW_AND_SAFE 1
 
 static struct ftdi_context ftdic;
-static unsigned int usb_maxlen = 0;
 static unsigned char bitbang_mode;
 
 static int jtagkey_init(unsigned short vid, unsigned short pid) {
@@ -36,15 +36,15 @@ static int jtagkey_init(unsigned short vid, unsigned short pid) {
                return ret;
        }
 
+       if ((ret = ftdi_write_data_set_chunksize(&ftdic, USBBUFSIZE))  != 0) {
+               fprintf(stderr, "unable to set write chunksize: %d (%s)\n", ret, ftdi_get_error_string(&ftdic));
+               return ret;
+       }
 
-#ifdef SLOW_AND_SAFE
-       usb_maxlen = 384;
-#else
-       if ((ret = ftdi_write_data_get_chunksize(&ftdic, &usb_maxlen))  != 0) {
-               fprintf(stderr, "unable to get write chunksize: %d (%s)\n", ret, ftdi_get_error_string(&ftdic));
+       if ((ret = ftdi_read_data_set_chunksize(&ftdic, USBBUFSIZE))  != 0) {
+               fprintf(stderr, "unable to set read chunksize: %d (%s)\n", ret, ftdi_get_error_string(&ftdic));
                return ret;
        }
-#endif
 
        if ((ret = ftdi_set_latency_timer(&ftdic, 1))  != 0) {
                fprintf(stderr, "unable to set latency timer: %d (%s)\n", ret, ftdi_get_error_string(&ftdic));
@@ -93,6 +93,7 @@ void jtagkey_close(int handle) {
        }
 }
 
+#ifndef SLOW_AND_SAFE
 static int jtagkey_set_bbmode(unsigned char mode) {
        int ret = 0;
 
@@ -117,6 +118,7 @@ static int jtagkey_set_bbmode(unsigned char mode) {
 
        return ret;
 }
+#endif
 
 void jtagkey_state(unsigned char data) {
        fprintf(stderr,"Pins high: ");
@@ -139,6 +141,25 @@ void jtagkey_state(unsigned char data) {
        fprintf(stderr,"\n");
 }
 
+struct jtagkey_reader_arg {
+       int             num;
+       unsigned char   *buf;
+};
+
+static void *jtagkey_reader(void *thread_arg) {
+       struct jtagkey_reader_arg *arg = (struct jtagkey_reader_arg*)thread_arg;
+
+       int i;
+
+       i = 0;
+       DPRINTF("reader for %d bytes\n", arg->num);
+       while (i < arg->num) {
+               i += ftdi_read_data(&ftdic, arg->buf + i, arg->num - i);
+       }
+       
+       pthread_exit(NULL);
+}
+
 int jtagkey_transfer(WD_TRANSFER *tr, int fd, unsigned int request, int ppbase, int ecpbase, int num) {
        int ret = 0;
        int i;
@@ -150,6 +171,8 @@ int jtagkey_transfer(WD_TRANSFER *tr, int fd, unsigned int request, int ppbase,
        static unsigned char writebuf[USBBUFSIZE], *writepos = writebuf;
        static unsigned char readbuf[USBBUFSIZE], *readpos;
        unsigned char data, prev_data;
+       struct jtagkey_reader_arg targ;
+       pthread_t reader_thread;
 
        /* Count reads */
        for (i = 0; i < num; i++)
@@ -160,27 +183,30 @@ int jtagkey_transfer(WD_TRANSFER *tr, int fd, unsigned int request, int ppbase,
        if ((writepos-writebuf > sizeof(writebuf)-num) || (nread && writepos-writebuf)) {
                unsigned char *pos = writebuf;
                int len;
+
                DPRINTF("writing %d bytes due to %d following reads in %d chunks or full buffer\n", writepos-writebuf, nread, num);
 
 #ifndef SLOW_AND_SAFE
                jtagkey_set_bbmode(BITMODE_BITBANG);
+#endif
+#ifdef SLOW_AND_SAFE
+               targ.num = writepos-pos;
+               targ.buf = readbuf;
+               pthread_create(&reader_thread, NULL, &jtagkey_reader, &targ);
 #endif
                while (pos < writepos) {
                        len = writepos-pos;
 
-                       if (len > usb_maxlen)
-                               len = usb_maxlen;
+                       if (len > USBBUFSIZE)
+                               len = USBBUFSIZE;
 
                        DPRINTF("combined write of %d/%d\n",len,writepos-pos);
                        ftdi_write_data(&ftdic, pos, len);
-#ifdef SLOW_AND_SAFE
-                       i = 0;
-                       while (i < len) {
-                               i += ftdi_read_data(&ftdic, readbuf, sizeof(readbuf));
-                       }
-#endif
                        pos += len;
                }
+#ifdef SLOW_AND_SAFE
+               pthread_join(reader_thread, NULL);
+#endif
 
                writepos = writebuf;
        }
@@ -256,7 +282,7 @@ int jtagkey_transfer(WD_TRANSFER *tr, int fd, unsigned int request, int ppbase,
                        }
                }
 
-               if (nread || (*writepos != prev_data))
+               if (nread || (*writepos != prev_data) || (i == num-1))
                        writepos++;
        }
 
@@ -267,13 +293,14 @@ int jtagkey_transfer(WD_TRANSFER *tr, int fd, unsigned int request, int ppbase,
                *writepos = last_data;
                writepos++;
 
+#ifndef SLOW_AND_SAFE
                jtagkey_set_bbmode(BITMODE_SYNCBB);
+#endif
+               targ.num = writepos-writebuf;
+               targ.buf = readbuf;
+               pthread_create(&reader_thread, NULL, &jtagkey_reader, &targ);
                ftdi_write_data(&ftdic, writebuf, writepos-writebuf);
-
-               i = 0;
-               while (i < writepos-writebuf) {
-                       i += ftdi_read_data(&ftdic, readbuf, sizeof(readbuf));
-               }
+               pthread_join(reader_thread, NULL);
 
 #ifdef DEBUG
                DPRINTF("write: ");