From 270200e972e6c2a5733a12ee70fcc3b7e2940c6c Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Thu, 8 Sep 2022 09:41:12 +0200 Subject: score: Remove _CPU_Counter_difference() All CPU ports used the same _CPU_Counter_difference() implementation. Remove this CPU port interface and mandate a monotonically increasing CPU counter. Close #3456. --- cpukit/score/cpu/no_cpu/include/rtems/score/cpu.h | 39 +++++++---------------- 1 file changed, 11 insertions(+), 28 deletions(-) (limited to 'cpukit/score/cpu/no_cpu/include') diff --git a/cpukit/score/cpu/no_cpu/include/rtems/score/cpu.h b/cpukit/score/cpu/no_cpu/include/rtems/score/cpu.h index 5403cc8a10..63829b5272 100644 --- a/cpukit/score/cpu/no_cpu/include/rtems/score/cpu.h +++ b/cpukit/score/cpu/no_cpu/include/rtems/score/cpu.h @@ -1293,44 +1293,27 @@ static inline uint32_t CPU_swap_u32( typedef uint32_t CPU_Counter_ticks; /** - * @brief Returns the current CPU counter frequency in Hz. + * @brief Gets the current CPU counter frequency in Hz. * - * @return The current CPU counter frequency in Hz. + * @return Returns the current CPU counter frequency in Hz. */ uint32_t _CPU_Counter_frequency( void ); /** - * @brief Returns the current CPU counter value. + * @brief Gets the current CPU counter value. * - * A CPU counter is some free-running counter. It ticks usually with a - * frequency close to the CPU or system bus clock. The board support package - * must ensure that this function works before the RTEMS initialization. - * Otherwise invalid profiling statistics will be gathered. + * A CPU counter should be some monotonically increasing free-running counter. + * It ticks usually with a frequency close to the CPU or system bus clock. The + * counter should not be affected by power saving states so that it can be used + * for timestamps. The CPU counter should be initialized at the + * RTEMS_SYSINIT_CPU_COUNTER initialization step if necessary. If + * RTEMS_PROFILING is enabled, the CPU counter may have to work very early in + * the system initialization to avoid invalid profiling statistics. * - * @return The current CPU counter value. + * @return Returns the current CPU counter value. */ CPU_Counter_ticks _CPU_Counter_read( void ); -/** - * @brief Returns the difference between the second and first CPU counter - * value. - * - * This operation may be carried out as a modulo operation depending on the - * range of the CPU counter device. - * - * @param[in] second The second CPU counter value. - * @param[in] first The first CPU counter value. - * - * @return Returns second minus first modulo counter period. - */ -static inline CPU_Counter_ticks _CPU_Counter_difference( - CPU_Counter_ticks second, - CPU_Counter_ticks first -) -{ - return second - first; -} - #ifdef RTEMS_SMP /** * @brief Performs CPU specific SMP initialization in the context of the boot -- cgit v1.2.3