X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/90858b95ad0ae44ed2fdf2e7525c170135ce00b7..913a54a86accab2a6959c4fcaf53711502f2d954:/armsrc/util.c

diff --git a/armsrc/util.c b/armsrc/util.c
index 1dd8dc75..59dfe07b 100644
--- a/armsrc/util.c
+++ b/armsrc/util.c
@@ -292,6 +292,7 @@ void FormatVersionInformation(char *dst, int len, const char *prefix, void *vers
 	strncat(dst, "\n", len - strlen(dst) - 1);
 }
 
+
 //  -------------------------------------------------------------------------
 //  timer lib
 //  -------------------------------------------------------------------------
@@ -312,6 +313,7 @@ void StartTickCount()
 	// note: worst case precision is approx 2.5%
 }
 
+
 /*
 * Get the current count.
 */
@@ -319,6 +321,7 @@ uint32_t RAMFUNC GetTickCount(){
 	return AT91C_BASE_RTTC->RTTC_RTVR;// was * 2;
 }
 
+
 //  -------------------------------------------------------------------------
 //  microseconds timer 
 //  -------------------------------------------------------------------------
@@ -344,10 +347,12 @@ void StartCountUS()
 	AT91C_BASE_TCB->TCB_BCR = 1;
 	}
 
+
 uint32_t RAMFUNC GetCountUS(){
-	return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV / 15) * 10);
+	return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV * 2) / 3); //was  /15) * 10);
 }
 
+
 static uint32_t GlobalUsCounter = 0;
 
 uint32_t RAMFUNC GetDeltaCountUS(){
@@ -402,7 +407,7 @@ void StartCountSspClk()
 	AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN;				// enable TC2
 
 	//
-	// synchronize the counter with the ssp_frame signal. Note: FPGA must be in any iso14446 mode, otherwise the frame signal would not be present 
+	// synchronize the counter with the ssp_frame signal. Note: FPGA must be in any iso14443 mode, otherwise SSC_FRAME and SSC_CLK signals would not be present 
 	//
 	while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME)); 	// wait for ssp_frame to go high (start of frame)
 	while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME); 		// wait for ssp_frame to be low
@@ -416,7 +421,17 @@ void StartCountSspClk()
 	// (just started with the transfer of the 4th Bit).
 	// The high word of the counter (TC2) will not reset until the low word (TC0) overflows. Therefore need to wait quite some time before
 	// we can use the counter.
-	while (AT91C_BASE_TC0->TC_CV < 0xFFF0);
+	while (AT91C_BASE_TC0->TC_CV < 0xFFFF);
+	// Note: needs one more SSP_CLK cycle (1.18 us) until TC2 resets. Don't call GetCountSspClk() that soon.
+}
+
+
+void ResetSspClk(void) {
+	//enable clock of timer and software trigger
+	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	while (AT91C_BASE_TC2->TC_CV > 0);
 }
 
 
@@ -431,3 +446,92 @@ uint32_t RAMFUNC GetCountSspClk(){
 	}
 }
 
+
+//  -------------------------------------------------------------------------
+//  Timer for bitbanging,  or LF stuff when you need a very precis timer
+//  1us = 1.5ticks
+//  -------------------------------------------------------------------------
+void StartTicks(void){
+	//initialization of the timer
+	// tc1 is higher 0xFFFF0000
+	// tc0 is lower 0x0000FFFF
+	AT91C_BASE_PMC->PMC_PCER |= (1 << AT91C_ID_TC0) | (1 << AT91C_ID_TC1);
+	AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE;
+	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS;
+	AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK | // MCK(48MHz) / 32 
+								AT91C_TC_WAVE | AT91C_TC_WAVESEL_UP_AUTO | AT91C_TC_ACPA_CLEAR |
+								AT91C_TC_ACPC_SET | AT91C_TC_ASWTRG_SET;
+	AT91C_BASE_TC0->TC_RA = 1;
+	AT91C_BASE_TC0->TC_RC = 0; 
+
+	AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS;	// timer disable  
+	AT91C_BASE_TC1->TC_CMR = AT91C_TC_CLKS_XC1; // from TC0
+	
+	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	AT91C_BASE_TCB->TCB_BCR = 1;
+	
+	// wait until timer becomes zero.
+	while (AT91C_BASE_TC1->TC_CV > 0);
+}
+
+
+// Wait - Spindelay in ticks.
+// if called with a high number, this will trigger the WDT...
+void WaitTicks(uint32_t ticks){
+	if ( ticks == 0 ) return;
+	ticks += GET_TICKS;	
+	while (GET_TICKS < ticks);
+}
+
+
+// Wait / Spindelay in us (microseconds) 
+// 1us = 1.5ticks.
+void WaitUS(uint16_t us){
+	if ( us == 0 ) return;
+	WaitTicks( (uint32_t)us * 3 / 2 ) ;
+}
+
+
+void WaitMS(uint16_t ms){
+	if (ms == 0) return;
+	WaitTicks( (uint32_t)ms * 1500 );
+}
+
+
+// Starts Clock and waits until its reset
+void ResetTicks(void){
+	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	while (AT91C_BASE_TC1->TC_CV > 0);
+}
+
+
+void ResetTimer(AT91PS_TC timer){
+	timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+	while(timer->TC_CV > 0) ;
+}
+
+
+// stop clock
+void StopTicks(void){
+	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS;
+	AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS;	
+}
+
+
+static uint64_t next_random = 1;
+
+/* Generates a (non-cryptographically secure) 32-bit random number.
+ *
+ * We don't have an implementation of the "rand" function or a clock to seed it
+ * with, so we just call GetTickCount the first time to seed ourselves.
+ */
+uint32_t prand() {
+	if (next_random == 1) {
+		next_random = GetTickCount();
+	}
+
+	next_random = next_random * 6364136223846793005 + 1;
+	return (uint32_t)(next_random >> 32) % 0xffffffff;
+}