Unnamed repository; edit this file 'description' to name the repository. http://cgit.235523.xyz/tinyusb.git/atom/hw/bsp/maxim/sysview_max32_tmr.h?h=claude%2Fadd-systemview-debug 2026-09-03T21:21:57Z 2026-09-03T21:21:57Z hathach thach@tinyusb.org 2026-09-03T10:14:28Z urn:sha1:5a0d707dd96ae7821d97793b441b86aabb684855 Cortex-M0/M0+, the WCH RISC-V parts and MAX3266x have no usable DWT cycle counter, so their family.c provides SEGGER_SYSVIEW_X_GetTimestamp() from a free-running hardware timer: a 32-bit general-purpose timer on ST parts (sysview_stm32_tim2.h), SysTick-extended sources on the M0 families, the core's SysTick-equivalent on WCH with the documented ordered read of the split count registers (sysview_wch_timestamp.h), and a TMR on MAX3266x (sysview_max32_tmr.h). max32666fthr's DWT implements only watchpoint comparators (DWT_CTRL.NOCYCCNT=1 read live; UG6971 documents no DWT/trace at all), so SystemView's ARMv7-M default read 0xE0001004 as a frozen 0 and every duration decoded as zero. The TMR runs at 48 MHz (f_PCLK = f_SYS_CLK/2; Continuous mode, CMP=0xFFFFFFFF, prescaler 1 - UG6971 15.2 guarantees TMRn_CNT readable while counting); TMR0 by default - present on every MAX32 part, unused by the examples, FreeRTOS ticks on SysTick - overridable with -DSYSVIEW_MAX32_TMR=n. The family builds SystemView with SEGGER_SYSVIEW_CORE_OTHER and sets CFG_TUSB_SYSVIEW_TIMESTAMP_BSP, a tusb_sysview.c opt-in for ARMv7-M parts without CYCCNT where the BSP also reports the rate via SEGGER_SYSVIEW_X_GetTimestampFreq(); the fixed-1MHz microsecond contract is unreachable on a powers-of-two-only prescaler. SEGGER_SYSVIEW_X_GetInterruptId() gains the ICSR.VECTACTIVE read for CORE_OTHER builds. MAX32650/32690 use different GCR clock-gate names and stay unported. Measured on the rig: seven host-timed 1.000 s gaps at 1.00044-1.00091 (median +0.05%). stm32f0 refuses to configure SYSVIEW for stm32f070xb at CMake time: that variant has no TIM2 at all, and the alternative was an undefined-reference link error with no hint. The shared hw/bsp/sysview_*.h join ci_select rule 16's hw/bsp file list (cross-family build files, compiled only under -DSYSVIEW which no CI leg enables), mirrored in the spec's rule table, so master's classification guard resolves them on both axes.