]> git.zerfleddert.de Git - proxmark3-svn/blob - armsrc/ticks.c
ADD; added some more descriptions of what the legic prng imp does.
[proxmark3-svn] / armsrc / ticks.c
1 //-----------------------------------------------------------------------------
2 // Jonathan Westhues, Sept 2005
3 // Iceman, Sept 2016
4 //
5 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
6 // at your option, any later version. See the LICENSE.txt file for the text of
7 // the license.
8 //-----------------------------------------------------------------------------
9 // Timers, Clocks functions used in LF or Legic where you would need detailed time.
10 //-----------------------------------------------------------------------------
11
12 #include "ticks.h"
13
14 // attempt at high resolution microsecond timer
15 // beware: timer counts in 21.3uS increments (1024/48Mhz)
16 void SpinDelayUs(int us) {
17 int ticks = (48 * us) >> 10;
18
19 // Borrow a PWM unit for my real-time clock
20 AT91C_BASE_PWMC->PWMC_ENA = PWM_CHANNEL(0);
21
22 // 48 MHz / 1024 gives 46.875 kHz
23 AT91C_BASE_PWMC_CH0->PWMC_CMR = PWM_CH_MODE_PRESCALER(10);
24 AT91C_BASE_PWMC_CH0->PWMC_CDTYR = 0;
25 AT91C_BASE_PWMC_CH0->PWMC_CPRDR = 0xffff;
26
27 uint16_t start = AT91C_BASE_PWMC_CH0->PWMC_CCNTR;
28
29 for(;;) {
30 uint16_t now = AT91C_BASE_PWMC_CH0->PWMC_CCNTR;
31 if (now == (uint16_t)(start + ticks))
32 return;
33
34 WDT_HIT();
35 }
36 }
37
38 void SpinDelay(int ms) {
39 // convert to uS and call microsecond delay function
40 SpinDelayUs(ms*1000);
41 }
42 // -------------------------------------------------------------------------
43 // timer lib
44 // -------------------------------------------------------------------------
45 // test procedure:
46 //
47 // ti = GetTickCount();
48 // SpinDelay(1000);
49 // ti = GetTickCount() - ti;
50 // Dbprintf("timer(1s): %d t=%d", ti, GetTickCount());
51 void StartTickCount(void) {
52 // This timer is based on the slow clock. The slow clock frequency is between 22kHz and 40kHz.
53 // We can determine the actual slow clock frequency by looking at the Main Clock Frequency Register.
54 uint16_t mainf = AT91C_BASE_PMC->PMC_MCFR & 0xffff; // = 16 * main clock frequency (16MHz) / slow clock frequency
55 // set RealTimeCounter divider to count at 1kHz:
56 AT91C_BASE_RTTC->RTTC_RTMR = AT91C_RTTC_RTTRST | ((256000 + (mainf/2)) / mainf);
57 // note: worst case precision is approx 2.5%
58 }
59
60 /*
61 * Get the current count.
62 */
63 uint32_t RAMFUNC GetTickCount(void){
64 return AT91C_BASE_RTTC->RTTC_RTVR;// was * 2;
65 }
66
67 // -------------------------------------------------------------------------
68 // microseconds timer
69 // -------------------------------------------------------------------------
70 void StartCountUS(void) {
71 AT91C_BASE_PMC->PMC_PCER |= (1 << 12) | (1 << 13) | (1 << 14);
72 AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE;
73
74 // fast clock
75 // tick=1.5mks
76 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
77 AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK | // MCK(48MHz) / 32
78 AT91C_TC_WAVE | AT91C_TC_WAVESEL_UP_AUTO | AT91C_TC_ACPA_CLEAR |
79 AT91C_TC_ACPC_SET | AT91C_TC_ASWTRG_SET;
80 AT91C_BASE_TC0->TC_RA = 1;
81 AT91C_BASE_TC0->TC_RC = 0xBFFF + 1; // 0xC000
82
83 AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // timer disable
84 AT91C_BASE_TC1->TC_CMR = AT91C_TC_CLKS_XC1; // from timer 0
85
86 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
87 AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
88 AT91C_BASE_TCB->TCB_BCR = 1;
89
90 while (AT91C_BASE_TC1->TC_CV >= 1);
91 }
92
93 uint32_t RAMFUNC GetCountUS(void){
94 //return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV / 15) * 10);
95 // By suggestion from PwPiwi, http://www.proxmark.org/forum/viewtopic.php?pid=17548#p17548
96 return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV * 2) / 3);
97 }
98
99
100 // -------------------------------------------------------------------------
101 // Timer for iso14443 commands. Uses ssp_clk from FPGA
102 // -------------------------------------------------------------------------
103 void StartCountSspClk(void) {
104 AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_TC0) | (1 << AT91C_ID_TC1) | (1 << AT91C_ID_TC2); // Enable Clock to all timers
105 AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_TIOA1 // XC0 Clock = TIOA1
106 | AT91C_TCB_TC1XC1S_NONE // XC1 Clock = none
107 | AT91C_TCB_TC2XC2S_TIOA0; // XC2 Clock = TIOA0
108
109 // configure TC1 to create a short pulse on TIOA1 when a rising edge on TIOB1 (= ssp_clk from FPGA) occurs:
110 AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // disable TC1
111 AT91C_BASE_TC1->TC_CMR = AT91C_TC_CLKS_TIMER_DIV1_CLOCK // TC1 Clock = MCK(48MHz)/2 = 24MHz
112 | AT91C_TC_CPCSTOP // Stop clock on RC compare
113 | AT91C_TC_EEVTEDG_RISING // Trigger on rising edge of Event
114 | AT91C_TC_EEVT_TIOB // Event-Source: TIOB1 (= ssp_clk from FPGA = 13,56MHz/16)
115 | AT91C_TC_ENETRG // Enable external trigger event
116 | AT91C_TC_WAVESEL_UP // Upmode without automatic trigger on RC compare
117 | AT91C_TC_WAVE // Waveform Mode
118 | AT91C_TC_AEEVT_SET // Set TIOA1 on external event
119 | AT91C_TC_ACPC_CLEAR; // Clear TIOA1 on RC Compare
120 AT91C_BASE_TC1->TC_RC = 0x04; // RC Compare value = 0x04
121
122 // use TC0 to count TIOA1 pulses
123 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // disable TC0
124 AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_XC0 // TC0 clock = XC0 clock = TIOA1
125 | AT91C_TC_WAVE // Waveform Mode
126 | AT91C_TC_WAVESEL_UP // just count
127 | AT91C_TC_ACPA_CLEAR // Clear TIOA0 on RA Compare
128 | AT91C_TC_ACPC_SET; // Set TIOA0 on RC Compare
129 AT91C_BASE_TC0->TC_RA = 1; // RA Compare value = 1; pulse width to TC2
130 AT91C_BASE_TC0->TC_RC = 0; // RC Compare value = 0; increment TC2 on overflow
131
132 // use TC2 to count TIOA0 pulses (giving us a 32bit counter (TC0/TC2) clocked by ssp_clk)
133 AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKDIS; // disable TC2
134 AT91C_BASE_TC2->TC_CMR = AT91C_TC_CLKS_XC2 // TC2 clock = XC2 clock = TIOA0
135 | AT91C_TC_WAVE // Waveform Mode
136 | AT91C_TC_WAVESEL_UP; // just count
137
138 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; // enable and reset TC0
139 AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; // enable and reset TC1
140 AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; // enable and reset TC2
141
142 // synchronize the counter with the ssp_frame signal.
143 // Note: FPGA must be in any iso14443 mode, otherwise the frame signal would not be present
144 while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME)); // wait for ssp_frame to go high (start of frame)
145 while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME); // wait for ssp_frame to be low
146 while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)); // wait for ssp_clk to go high
147
148 // note: up to now two ssp_clk rising edges have passed since the rising edge of ssp_frame
149 // it is now safe to assert a sync signal. This sets all timers to 0 on next active clock edge
150 AT91C_BASE_TCB->TCB_BCR = 1; // assert Sync (set all timers to 0 on next active clock edge)
151 // at the next (3rd) ssp_clk rising edge, TC1 will be reset (and not generate a clock signal to TC0)
152 // at the next (4th) ssp_clk rising edge, TC0 (the low word of our counter) will be reset. From now on,
153 // whenever the last three bits of our counter go 0, we can be sure to be in the middle of a frame transfer.
154 // (just started with the transfer of the 4th Bit).
155
156 // The high word of the counter (TC2) will not reset until the low word (TC0) overflows.
157 // Therefore need to wait quite some time before we can use the counter.
158 while (AT91C_BASE_TC2->TC_CV >= 1);
159 }
160 void ResetSspClk(void) {
161 //enable clock of timer and software trigger
162 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
163 AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
164 AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
165 while (AT91C_BASE_TC2->TC_CV >= 1);
166 }
167
168 uint32_t RAMFUNC GetCountSspClk(void) {
169 uint32_t tmp_count = (AT91C_BASE_TC2->TC_CV << 16) | AT91C_BASE_TC0->TC_CV;
170 if ((tmp_count & 0x0000ffff) == 0) //small chance that we may have missed an increment in TC2
171 return (AT91C_BASE_TC2->TC_CV << 16);
172 return tmp_count;
173 }
174
175
176 // -------------------------------------------------------------------------
177 // Timer for bitbanging, or LF stuff when you need a very precis timer
178 // 1us = 1.5ticks
179 // -------------------------------------------------------------------------
180 void StartTicks(void){
181 //initialization of the timer
182 AT91C_BASE_PMC->PMC_PCER |= (1 << 12) | (1 << 13) | (1 << 14);
183 AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE;
184 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS;
185 AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK; //clock at 48/32 MHz
186 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
187 AT91C_BASE_TCB->TCB_BCR = 1;
188 // wait until timer becomes zero.
189 while (AT91C_BASE_TC0->TC_CV > 1);
190 }
191 // Wait - Spindelay in ticks.
192 // if called with a high number, this will trigger the WDT...
193 void WaitTicks(uint32_t ticks){
194 if ( ticks == 0 ) return;
195 ticks += GET_TICKS;
196 while (GET_TICKS < ticks);
197 }
198 // Wait / Spindelay in us (microseconds)
199 // 1us = 1.5ticks.
200 void WaitUS(uint16_t us){
201 if ( us == 0 ) return;
202 WaitTicks( (uint32_t)(us * 1.5) );
203 }
204 void WaitMS(uint16_t ms){
205 if (ms == 0) return;
206 WaitTicks( (uint32_t)(ms * 1500) );
207 }
208 // Starts Clock and waits until its reset
209 void ResetTicks(){
210 ResetTimer(AT91C_BASE_TC0);
211 }
212 void ResetTimer(AT91PS_TC timer){
213 timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
214 while(timer->TC_CV > 1) ;
215 }
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