hw/timer/imx_epit: cleanup CR defines

remove unused defines, add needed defines

Signed-off-by: Axel Heider <axel.heider@hensoldt.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/timer/imx_epit.c

@@ -82,8 +82,8 @@ static void imx_epit_set_freq(IMXEPITState *s)
     uint32_t clksrc;
     uint32_t prescaler;
 
-    clksrc = extract32(s->cr, CR_CLKSRC_SHIFT, 2);
-    prescaler = 1 + extract32(s->cr, CR_PRESCALE_SHIFT, 12);
+    clksrc = extract32(s->cr, CR_CLKSRC_SHIFT, CR_CLKSRC_BITS);
+    prescaler = 1 + extract32(s->cr, CR_PRESCALE_SHIFT, CR_PRESCALE_BITS);
 
     s->freq = imx_ccm_get_clock_frequency(s->ccm,
                                 imx_epit_clocks[clksrc]) / prescaler;

include/hw/timer/imx_epit.h

@@ -43,7 +43,7 @@
 #define CR_OCIEN    (1 << 2)
 #define CR_RLD      (1 << 3)
 #define CR_PRESCALE_SHIFT (4)
-#define CR_PRESCALE_MASK  (0xfff)
+#define CR_PRESCALE_BITS  (12)
 #define CR_SWR      (1 << 16)
 #define CR_IOVW     (1 << 17)
 #define CR_DBGEN    (1 << 18)
@@ -51,7 +51,7 @@
 #define CR_DOZEN    (1 << 20)
 #define CR_STOPEN   (1 << 21)
 #define CR_CLKSRC_SHIFT (24)
-#define CR_CLKSRC_MASK  (0x3 << CR_CLKSRC_SHIFT)
+#define CR_CLKSRC_BITS  (2)
 
 #define EPIT_TIMER_MAX  0XFFFFFFFFUL