Copy over the relevant changes from the sniffonly branch pending integration

git-svn-id: https://svn.openpcd.org:2342/trunk@442 6dc7ffe9-61d6-0310-9af1-9938baff3ed1

11 files changed, 228 insertions, 119 deletions

diff --git a/openpicc/Makefile b/openpicc/Makefile
index 25ee436..d826582 100644
--- a/openpicc/Makefile
+++ b/openpicc/Makefile
@@ -96,6 +96,7 @@ ARM_SRC= \
   application/decoder_miller.c \
   application/decoder_nrzl.c \
   application/decoder.c \
+  application/tc_sniffer.c \
   os/boot/Cstartup_SAM7.c \
   os/core/list.c \
   os/core/queue.c \
diff --git a/openpicc/application/cmd.c b/openpicc/application/cmd.c
index 47bbec5..50b59d3 100644
--- a/openpicc/application/cmd.c
+++ b/openpicc/application/cmd.c
@@ -21,6 +21,7 @@
 #include "ssc.h"
 #include "usb_print.h"
 #include "load_modulation.h"
+#include "tc_sniffer.h"
 
 xQueueHandle xCmdQueue;
 xTaskHandle xCmdTask;
@@ -45,7 +46,7 @@ static const portBASE_TYPE USE_COLON_FOR_LONG_COMMANDS = 0;
 /* When not USE_COLON_FOR_LONG_COMMANDS then short commands will be recognized by including
  * their character in the string SHORT_COMMANDS
  * */
-static const char *SHORT_COMMANDS = "!pc+-l?hq9fjka#i";
+static const char *SHORT_COMMANDS = "!prc+-l?hq9fjka#i";
 /* Note that the long/short command distinction only applies to the USB serial console
  * */
 
@@ -241,6 +242,9 @@ void prvExecCommand(u_int32_t cmd, portCHAR *args) {
 		case 'P':
 		    print_pio();
 		    break;
+		case 'R':
+			start_stop_sniffing();
+			break;
 		case 'C':
 		    DumpStringToUSB(
 			" *****************************************************\n\r"
@@ -442,6 +446,7 @@ void prvExecCommand(u_int32_t cmd, portCHAR *args) {
 		    " * #    - switch clock\n\r"
 			" * l    - cycle LEDs\n\r"
 			" * p    - print PIO pins\n\r"
+		    " * r    - start/stop receiving\n\r"
 			" * z 0/1- enable or disable tc_cdiv_sync\n\r"
 			" * i    - inhibit/uninhibit PLL\n\r"
 			" * !    - reset tc_cdiv_sync\n\r"
diff --git a/openpicc/application/main.c b/openpicc/application/main.c
index 2397c61..9b81aea 100644
--- a/openpicc/application/main.c
+++ b/openpicc/application/main.c
@@ -51,6 +51,7 @@
 #include "iso14443_sniffer.h"
 #include "iso14443a_pretender.h"
 #include "decoder.h"
+#include "tc_sniffer.h"
 
 static inline int detect_board(void)
 {
@@ -210,9 +211,12 @@ int main (void)
 	NULL, TASK_ISO_PRIORITY, NULL);*/
     /*xTaskCreate (iso14443_sniffer, (signed portCHAR *) "ISO14443-SNIFF", TASK_ISO_STACK,
 	NULL, TASK_ISO_PRIORITY, NULL);*/
-    xTaskCreate (iso14443a_pretender, (signed portCHAR *) "ISO14443A-PRETEND", TASK_ISO_STACK,
-	NULL, TASK_ISO_PRIORITY, NULL);
-    
+    /*xTaskCreate (iso14443a_pretender, (signed portCHAR *) "ISO14443A-PRETEND", TASK_ISO_STACK,
+	NULL, TASK_ISO_PRIORITY, NULL);*/
+    xTaskCreate (tc_sniffer, (signed portCHAR *) "RFID-SNIFFER", TASK_ISO_STACK,
+		 	NULL, TASK_ISO_PRIORITY, NULL);
+
+	    
     xTaskCreate (vUSBCDCTask, (signed portCHAR *) "USB", TASK_USB_STACK,
 	NULL, TASK_USB_PRIORITY, NULL);
 	
diff --git a/openpicc/application/ssc.c b/openpicc/application/ssc.c
index 50d416b..a490d42 100644
--- a/openpicc/application/ssc.c
+++ b/openpicc/application/ssc.c
@@ -43,9 +43,6 @@
 
 #define PRINT_DEBUG 0
 
-// BROKEN Old FIQ code
-int ssc_tx_pending=0, ssc_tx_fiq_fdt_cdiv=0, ssc_tx_fiq_fdt_ssc=0;
-
 struct _ssc_handle {
 	enum ssc_mode mode;
 	const struct openpicc_hardware *openpicc;
diff --git a/openpicc/application/tc_sniffer.c b/openpicc/application/tc_sniffer.c
new file mode 100644
index 0000000..abf04c0
--- /dev/null
+++ b/openpicc/application/tc_sniffer.c
@@ -0,0 +1,143 @@
+/***************************************************************
+ *
+ * OpenPICC - T/C based dumb sniffer
+ * 
+ * TC2 will reset its value on each falling edge of SSC_DATA, we
+ * will have the FIQ store the TC2 value on each rising edge of
+ * SSC_DATA. This will give us a count of carrier cycles between
+ * modulation pauses which should be enough information to decode
+ * the modified miller encoding.
+ *
+ * Copyright 2008 Henryk Plötz <henryk@ploetzli.ch>
+ *
+ ***************************************************************
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; version 2.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+*/
+
+#include <FreeRTOS.h>
+#include <openpicc.h>
+#include <task.h>
+#include <string.h>
+
+#include <USB-CDC.h>
+
+#include "tc_sniffer.h"
+#include "load_modulation.h"
+#include "pll.h"
+#include "tc_fdt.h"
+#include "usb_print.h"
+#include "cmd.h"
+#include "pio_irq.h"
+
+/* Problem: We want to receive data from the FIQ without locking (the FIQ must not be blocked ever)
+ * Strategy: Double buffering.
+ */
+
+#define BUFSIZE 1024
+#define WAIT_TICKS (20*portTICK_RATE_MS)
+typedef struct {
+	u_int32_t count;
+	u_int32_t data[BUFSIZE];
+} fiq_buffer_t;
+fiq_buffer_t fiq_buffers[2];
+
+fiq_buffer_t *tc_sniffer_next_buffer_for_fiq = 0;
+
+portBASE_TYPE currently_sniffing = 0;
+enum { NONE, REQUEST_START, REQUEST_STOP } request_change = NONE;
+
+#define MIN(a, b) ((a)>(b)?(b):(a))
+void flush_buffer(fiq_buffer_t *buffer)
+{
+	/* Write all data from the given buffer out, then zero the count */
+	if(buffer->count > 0) {
+		vUSBSendBuffer_blocking((unsigned char*)(&(buffer->data[0])), 0, MIN(buffer->count,BUFSIZE)*4, WAIT_TICKS);
+		if(buffer->count >= BUFSIZE)
+			vUSBSendBuffer_blocking((unsigned char*)"////", 0, 4, WAIT_TICKS);
+		else
+			vUSBSendBuffer_blocking((unsigned char*)"____", 0, 4, WAIT_TICKS);
+		buffer->count = 0;
+	}
+}
+
+void start_stop_sniffing(void)
+{
+	if(currently_sniffing)
+		request_change = REQUEST_STOP;
+	else
+		request_change = REQUEST_START;
+}
+
+void tc_sniffer (void *pvParameters)
+{
+	(void)pvParameters;
+	
+	/* Disable load modulation circuitry
+	 * (Must be done explicitly, because the default state is pull-up high, leading
+	 * to a constant modulation output which prevents reception. I've been bitten by
+	 * this more than once.)
+	 */
+	load_mod_init();
+	load_mod_level(0);
+	
+	pll_init();
+	pll_inhibit(0);
+	
+	tc_fdt_init();
+	
+	memset(fiq_buffers, 0, sizeof(fiq_buffers));
+	
+	/* Wait for the USB and CMD threads to start up */
+	vTaskDelay(1000 * portTICK_RATE_MS);
+	
+	// The change interrupt is going to be handled by the FIQ 
+	AT91F_PIO_CfgInput(AT91C_BASE_PIOA, OPENPICC_SSC_DATA);
+	pio_irq_enable(OPENPICC_SSC_DATA);
+	
+	int current = 0;
+	while(1) {
+		/* Main loop of the sniffer */
+		
+		if(currently_sniffing) {
+			int next = (current+1)%(sizeof(fiq_buffers)/sizeof(fiq_buffers[0]));
+			flush_buffer( &fiq_buffers[next] );
+			/* The buffer designated by next is now empty, give it to the fiq,
+			 * we'll just guess that this write is atomic */ 
+			tc_sniffer_next_buffer_for_fiq = &fiq_buffers[current=next];
+
+			if(request_change == REQUEST_STOP) {
+				currently_sniffing = 0;
+				request_change = NONE;
+				
+				tc_sniffer_next_buffer_for_fiq = 0;
+				memset(fiq_buffers, 0, sizeof(fiq_buffers));
+				current = 0;
+				vUSBSendBuffer_blocking((unsigned char *)"----", 0, 4, WAIT_TICKS);
+				usb_print_set_force_silence(0);
+			} else vTaskDelay(2* portTICK_RATE_MS);
+		} else {
+			// Do nothing, wait longer
+			
+			if(request_change == REQUEST_START) {
+				// Prevent usb_print code from barging in
+				usb_print_set_force_silence(1);
+				vUSBSendBuffer_blocking((unsigned char *)"----", 0, 4, WAIT_TICKS);
+				currently_sniffing = 1;
+				request_change = NONE;
+			} else vTaskDelay(100 * portTICK_RATE_MS);
+		}
+	}
+}
diff --git a/openpicc/application/tc_sniffer.h b/openpicc/application/tc_sniffer.h
new file mode 100644
index 0000000..e3a1c29
--- /dev/null
+++ b/openpicc/application/tc_sniffer.h
@@ -0,0 +1,7 @@
+#ifndef TC_SNIFFER_H_
+#define TC_SNIFFER_H_
+
+extern void tc_sniffer (void *pvParameters);
+extern void start_stop_sniffing (void);
+
+#endif /*TC_SNIFFER_H_*/
diff --git a/openpicc/application/usb_print.c b/openpicc/application/usb_print.c
index 5ff42b8..5e4372b 100644
--- a/openpicc/application/usb_print.c
+++ b/openpicc/application/usb_print.c
@@ -29,7 +29,7 @@
 
 static char ringbuffer[BUFLEN];
 static int ringstart, ringstop;
-static int default_flush = 1;
+static int default_flush = 1, forced_silence = 0;
 static xSemaphoreHandle print_semaphore;
 
 void usb_print_buffer(const char* buffer, int start, int stop) {
@@ -92,11 +92,20 @@ int usb_print_set_default_flush(int flush)
 	return old_flush;
 }
 
+int usb_print_set_force_silence(int silence)
+{
+	int old_silence = forced_silence;
+	forced_silence = silence;
+	return old_silence;
+}
+
 
 /* Must NOT be called from ISR context */
 void usb_print_flush(void)
 {
 	int oldstop, newstart;
+	if(forced_silence) return;
+	
 	taskENTER_CRITICAL();
 	if(print_semaphore == NULL)
 		usb_print_init();
diff --git a/openpicc/application/usb_print.h b/openpicc/application/usb_print.h
index 9186dc9..0497146 100644
--- a/openpicc/application/usb_print.h
+++ b/openpicc/application/usb_print.h
@@ -10,6 +10,7 @@ extern int usb_print_char_f(const char c, int flush);
 extern void usb_print_flush(void);
 extern int usb_print_get_default_flush(void);
 extern int usb_print_set_default_flush(int flush);
+extern int usb_print_set_force_silence(int silence);
 extern void usb_print_init(void);
 
 #endif /*USB_PRINT_H_*/
diff --git a/openpicc/os/boot/boot.s b/openpicc/os/boot/boot.s
index d9ac156..4fca262 100644
--- a/openpicc/os/boot/boot.s
+++ b/openpicc/os/boot/boot.s
@@ -4,9 +4,7 @@
 	.extern exit
 	.extern AT91F_LowLevelInit
 	.extern pio_irq_isr_value
-	.extern ssc_tx_pending
-	.extern ssc_tx_fiq_fdt_cdiv
-	.extern ssc_tx_fiq_fdt_ssc
+	.extern tc_sniffer_next_buffer_for_fiq
 
 	.text
 	.code 32
@@ -47,15 +45,14 @@
 .equ AT91C_BASE_MC,   (0xFFFFFF00)
 .equ AT91C_BASE_PIOA, 0xFFFFF400
 .equ AT91C_BASE_TC0,  0xFFFA0000
+.equ AT91C_BASE_TC2,  0xFFFA0080
 .equ AT91C_BASE_SSC,  0xFFFD4000
 .equ SSC_CR,          0x0
 .equ SSC_RCMR,        0x10
 .equ SSC_CR_TXEN,     0x100
 .equ AT91C_TC_SWTRG,  ((1 << 2)|1)
 .equ AT91C_TC_CLKEN,  (1 << 0)
-.equ PIO_DATA,        (1 << 27)
-.equ PIO_FRAME,       (1 << 20)
-.equ PIO_SSC_TF,      (1 << 15)
+.equ PIO_DATA,        (1 << 18)
 .equ PIOA_SODR,       0x30
 .equ PIOA_CODR,       0x34
 .equ PIOA_PDSR,       0x3c
@@ -71,6 +68,8 @@
 .equ PIO_SECONDARY_IRQ, 31
 .equ PIO_SECONDARY_IRQ_BIT, (1 << PIO_SECONDARY_IRQ)
 
+.equ BUFSIZE, 1024
+
 start:
 _start:
 _mainCRTStartup:
@@ -90,7 +89,6 @@ _mainCRTStartup:
     ldr     r10, =AT91C_BASE_PIOA
     ldr     r12, =AT91C_BASE_TC0
     ldr     r8, =AT91C_BASE_AIC
-    mov     r9, #AT91C_TC_SWTRG
     /*ldr     r9, =AT91C_BASE_SSC*/
     mov   sp, r0
     sub   r0, r0, #FIQ_STACK_SIZE
@@ -196,7 +194,7 @@ endless_loop:
 my_fiq_handler:
                 /* code that uses pre-initialized FIQ reg */
                 /* r8   tmp
-                   r9   AT91C_TC_SWTRG
+                   r9   tmp
                    r10  AT91C_BASE_PIOA
                    r11  tmp
                    r12  AT91C_BASE_TC0
@@ -215,111 +213,47 @@ my_fiq_handler:
                 str   r8, [r11]
                 
                 tst     r8, #PIO_DATA           /* check for PIO_DATA change */
-                ldrne   r11, [r10, #PIOA_PDSR]
-                tstne   r11, #PIO_DATA          /* check for PIO_DATA == 1 */
-                /*strne   r9, [r12, #TC_CCR]      /* software trigger */
-
-                movne   r11, #PIO_DATA
-                strne   r11, [r10, #PIOA_IDR]   /* disable further PIO_DATA FIQ */
-                beq .no_pio_data
-/* .loop_high:
-				ldr     r11, [r10, #PIOA_PDSR]
-				tst     r11, #PIO_DATA
-				bne     .loop_high
-                str   r9, [r12, #TC_CCR]      /* software trigger */
-
-.no_pio_data:
-                tst     r8, #PIO_SSC_TF         /* check for SSC Transmit Frame signal */
-                ldrne   r11, [r10, #PIOA_PDSR]
-                tstne   r11, #PIO_SSC_TF        /* check for SSC_TF == 1 */
-                
-                movne   r11, #PIO_SSC_TF
-                strne   r11, [r10, #PIOA_IDR]   /* disable further SSC_TF FIQ */
-                
-                ldrne   r11, =ssc_tx_pending
-                ldrne   r8, [r11]
-                tstne   r8, #0x01              /* Check whether a TX is pending */
-                beq     .no_ssc
-                b .no_ssc
+                beq     .no_buffer
                 
-                mov   r8, #PIO_LED1
-                str   r8, [r10, #PIOA_SODR] /* disable LED */
+                ldr   r11, [r10, #PIOA_PDSR]
+                tst   r11, #PIO_DATA          /* check for PIO_DATA == 1 */
+                beq   .no_buffer
+
+/*                mov     r11, #PIO_LED2
+                str     r11, [r10, #PIOA_CODR] /* enable LED */
+
+                /* Load the TC2.CV into r9 */
+                ldr r9, [r12, #TC2_CV]
                 
-                mov   r8, #0x00
-                str   r8, [r11]                /* Set ssc_tx_pending to 0 */
+                ldr r11, =tc_sniffer_next_buffer_for_fiq
+                ldr r11, [r11]
+                /* r11 now contains the value of tc_sniffer_next_buffer_for_fiq, e.q. the address
+                 * of the next buffer */
                 
-                ldr   r11, =ssc_tx_fiq_fdt_cdiv
-                ldr   r11, [r11]               /* r11 == ssc_tx_fiq_fdt_cdiv */
-
-/* Problem: LDR from the timer and loop still take too long and cause us to miss the exact time.
- * (One load-from-timer,compare,jump-back-if-less cycle are 7 CPU cycles, which are 2 carrier cycles.)
- * Strategy: Spin on TC2 till 3 or 4 carrier cycles before the actual time. Then go into an unrolled
- * 'loop' for the remaining time. (load-from-timer,compare,jump-forward-if-greater-or-equal are 5 CPU 
- * cycles if the condition is not reached.)
- * 
- * At 47.923200 MHz 7 processor cycles are 2 carrier cycles of the 13.56MHz carrier
- */
- .equ SUB_TIME, 4 /* subtract 4 carrier cycles == 14 processor cycles */
- 
- 				mov r8, #SUB_TIME
- 				sub r11, r11, r8              /* r11 == fdt_cdiv-SUB_TIME */
-
-.wait_for_fdt_cdiv:
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				blt   .wait_for_fdt_cdiv       /* spin while TC2.CV is less fdt_cdiv-SUB_TIME */
-				
-				mov r8, #SUB_TIME
-				add r11, r11, r8               /* r11 == fdt_cdiv */
-
-/* Seven copies of the loop contents, covering for 35 CPU cycles, or 10 carrier cycles */
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bge   .fdt_expired             /* jump forward if TC2.CV is greater than or equal fdt_cdiv */
-
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bge   .fdt_expired             
-
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bge   .fdt_expired             
-
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bge   .fdt_expired             
-
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bge   .fdt_expired             
-
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bge   .fdt_expired             
-
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bge   .fdt_expired             
-
-.fdt_expired:				
-				str   r9, [r12, #TC_CCR]       /* SWTRG on TC0 */
-				
-                ldr   r11, =ssc_tx_fiq_fdt_ssc
-                ldr   r11, [r11]               /* r11 == ssc_tx_fiq_fdt_ssc */
-
-.wait_for_fdt_ssc:
-				ldr   r8, [r12, #TC2_CV]
-				cmp   r8, r11
-				bmi   .wait_for_fdt_ssc        /* spin while TC2.CV is less fdt_ssc */
+                /* Jump to .no_buffer if the pointer is 0, indicating that no buffer is set */
+                cmp r11, #0
+                beq .no_buffer 
                 
-                mov   r11, #PIO_LED1
-                str   r11, [r10, #PIOA_CODR] /* enable LED */
+		/* Increment the value at the location the pointer points to */
+		ldr r8, [r11]
+		add r8, r8, #1
+		str r8, [r11]
+		
+		/* At this point:
+		   r8  = count
+		   r9  = TC2.CV
+		   r11 = pointer to buffer
+		 */
+		
+		cmp r8, #BUFSIZE
+		bge .no_buffer
+		
+		str r9, [r11, r8, LSL #2]
+		
+.no_buffer:
+/*                mov     r11, #PIO_LED2
+                str     r11, [r10, #PIOA_SODR] /* disable LED */
                 
-                ldr   r11, =AT91C_BASE_SSC
-                mov   r8, #SSC_CR_TXEN
-                str   r8, [r11, #SSC_CR]       /* Write TXEN to SSC_CR, enables tx */ 
-
-.no_ssc:               
                 /* Trigger PIO_SECONDARY_IRQ */
                 mov r11, #PIO_SECONDARY_IRQ_BIT
                 ldr r8, =AT91C_BASE_AIC
diff --git a/openpicc/os/usb/USB-CDC.c b/openpicc/os/usb/USB-CDC.c
index 1b840c9..c005597 100644
--- a/openpicc/os/usb/USB-CDC.c
+++ b/openpicc/os/usb/USB-CDC.c
@@ -123,7 +123,7 @@ transmitted.  Rx queue must be larger than FIFO size. */
 static xQueueHandle xRxCDC;
 static xQueueHandle xTxCDC;
 
-#define CHUNK_SIZE 8
+#define CHUNK_SIZE 9
 
 /* Line coding - 115,200 baud, N-8-1 */
 static const unsigned portCHAR pxLineCoding[] =
@@ -277,7 +277,7 @@ vUSBSendByte_blocking (portCHAR cByte, portTickType xTicksToWait)
 
 #define MIN(a,b) ((a)>(b)?(b):(a))
 void
-vUSBSendBuffer (unsigned char *buffer, portBASE_TYPE offset, portBASE_TYPE length)
+vUSBSendBuffer_blocking (unsigned char *buffer, portBASE_TYPE offset, portBASE_TYPE length, portTickType xTicksToWait)
 {
 	unsigned char chunk[CHUNK_SIZE];
 	while(length > 0) {
@@ -285,12 +285,19 @@ vUSBSendBuffer (unsigned char *buffer, portBASE_TYPE offset, portBASE_TYPE lengt
 		chunk[0] = next_size;
 		memcpy(chunk+1, buffer+offset, next_size);
 		/* Queue the bytes to be sent.  The USB task will send it. */
-		xQueueSend (xTxCDC, &chunk, usbNO_BLOCK);
+		xQueueSend (xTxCDC, &chunk, xTicksToWait);
 		length -= next_size;
 		offset += next_size;
 	}
 }
 
+void
+vUSBSendBuffer (unsigned char *buffer, portBASE_TYPE offset, portBASE_TYPE length)
+{
+	vUSBSendBuffer_blocking(buffer, offset, length, usbNO_BLOCK);
+}
+
+
 /*------------------------------------------------------------*/
 
 portLONG
diff --git a/openpicc/os/usb/USB-CDC.h b/openpicc/os/usb/USB-CDC.h
index 6074956..6c0a779 100644
--- a/openpicc/os/usb/USB-CDC.h
+++ b/openpicc/os/usb/USB-CDC.h
@@ -84,6 +84,7 @@ sent unless the port is connected. */
 void vUSBSendByte (portCHAR cByte);
 void vUSBSendByte_blocking (portCHAR cByte, portTickType xTicksToWait);
 void vUSBSendBuffer (unsigned char *buffer, portBASE_TYPE offset, portBASE_TYPE length);
+void vUSBSendBuffer_blocking (unsigned char *buffer, portBASE_TYPE offset, portBASE_TYPE length, portTickType xTicksToWait);
 portLONG vUSBRecvByte (portCHAR *cByte,portLONG size, portTickType xTicksToWait);
 
 #endif