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i.MX6: Fix comparison values in system timer setup. Clock was running 3x too fast.

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This commit is contained in:
Gregory Nutt 2016-05-17 10:08:06 -06:00
parent 1047d63f52
commit 0fe64839db
1 changed files with 19 additions and 4 deletions
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23
arch/arm/src/imx6/imx_timerisr.c
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@ -77,10 +77,25 @@
* We should be able to use a prescaler of 1. * We should be able to use a prescaler of 1.
*/ */
#define GPT_PR_VALUE 1 #define GPT_PR_VALUE 1
#define GPT_OCR3_VALUE ((GPT_CLOCK + ((1*CLK_TCK) >> 1)) / (1*CLK_TCK))
#define GPT_OCR2_VALUE ((GPT_CLOCK + ((2*CLK_TCK) >> 1)) / (2*CLK_TCK)) /* Timer counter comparison settings:
#define GPT_OCR1_VALUE ((GPT_CLOCK + ((3*CLK_TCK) >> 1)) / (3*CLK_TCK)) *
* - OCR3 will interrupt at CLK_TCK ticks/second after the timer counter
* has been reset.
* - OCR2 will interrupt at 2*CLK_TCK ticks/second after the timer counter
* has been reset.
* - OCR2 will interrupt at 3*CLK_TCK ticks/second after the timer counter
* has been reset and then will reset the timer, starting the 3 interrupt
* sequence again.
*
* Using three comparisons virtually eliminates the possibility of timer
* interrupt overrun.
*/
#define GPT_OCR3_VALUE ((1 * GPT_CLOCK + (CLK_TCK >> 1)) / CLK_TCK)
#define GPT_OCR2_VALUE ((2 * GPT_CLOCK + (CLK_TCK >> 1)) / CLK_TCK)
#define GPT_OCR1_VALUE ((3 * GPT_CLOCK + (CLK_TCK >> 1)) / CLK_TCK)
/**************************************************************************** /****************************************************************************
* Private Functions * Private Functions