github/proxmark3
1
0
Fork 0
mirror of https://github.com/Proxmark/proxmark3.git synced 2025-08-14 02:26:59 -07:00
Code Issues Projects Releases Packages Wiki Activity Actions

fix: avoid SspClk overflow due to incomplete reset

Browse source 
* should fix watchdog reset during hf mf mifare. Thanks @iceman1001 for the hint.
This commit is contained in:
pwpiwi 2017-11-21 07:31:42 +01:00 • committed by GitHub
commit 4058a2d7df
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 25 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

28
armsrc/util.c
View file

@ -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 * 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
@ -416,8 +421,11 @@ 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;
@ -425,6 +433,8 @@ void ResetSspClk(void) {
AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
while (AT91C_BASE_TC2->TC_CV > 0);
}
uint32_t RAMFUNC GetCountSspClk(){
uint32_t tmp_count;
tmp_count = (AT91C_BASE_TC2->TC_CV << 16) | AT91C_BASE_TC0->TC_CV;
@ -436,6 +446,7 @@ uint32_t RAMFUNC GetCountSspClk(){
}
}
// -------------------------------------------------------------------------
// Timer for bitbanging, or LF stuff when you need a very precis timer
// 1us = 1.5ticks
@ -464,6 +475,7 @@ void StartTicks(void){
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){
@ -471,32 +483,43 @@ void WaitTicks(uint32_t ticks){
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 * 1.5) );
}
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.
@ -512,4 +535,3 @@ uint32_t prand() {
next_random = next_random * 6364136223846793005 + 1;
return (uint32_t)(next_random >> 32) % 0xffffffff;
}