[Core] Use polled waiting on ChibiOS platforms that support it (#17607)
* Use polled waiting on platforms that support it Due to context switching overhead waiting a very short amount of time on a sleeping thread is often not accurate and in fact not usable for timing critical usage i.e. in a driver. Thus we use polled waiting for ranges in the us range on platforms that support it instead. The fallback is the thread sleeping mechanism. This includes: * ARM platforms with CYCCNT register (ARMv7, ARMv8) this is incremented at CPU clock frequency * GD32VF103 RISC-V port with CSR_MCYCLE register this is incremented at CPU clock frequency * RP2040 ARMv6 port which uses the integrated timer peripheral which is incremented with a fixed 1MHz frequency * Use wait_us() instead of chSysPolledDelayX ...as it is powered by busy waiting now. * Add chibios waiting methods test bench
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					 14 changed files with 126 additions and 31 deletions
				
			
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// Copyright 2022 Stefan Kerkmann
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// SPDX-License-Identifier: GPL-2.0-or-later
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#pragma once
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#if !defined(QMK_WAITING_TEST_BUSY_PIN)
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#    define QMK_WAITING_TEST_BUSY_PIN A8
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#endif
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#if !defined(QMK_WAITING_TEST_YIELD_PIN)
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#    define QMK_WAITING_TEST_YIELD_PIN A9
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#endif
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// Copyright 2022 Stefan Kerkmann
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// SPDX-License-Identifier: GPL-2.0-or-later
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#include QMK_KEYBOARD_H
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const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {LAYOUT_ortho_1x1(KC_A)};
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#if defined(__AVR__)
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#    pragma message "AVR uses polled waiting by default, running theses tests will not show any difference"
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static inline void chThdSleepMicroseconds(uint32_t us) {
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    wait_us(us);
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}
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#endif
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void keyboard_post_init_user(void) {
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    setPinOutput(QMK_WAITING_TEST_BUSY_PIN);
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    setPinOutput(QMK_WAITING_TEST_YIELD_PIN);
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}
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static inline void wait_us_polling_with_strobe(uint32_t us) {
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    writePinHigh(QMK_WAITING_TEST_BUSY_PIN);
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    wait_us(us);
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    writePinLow(QMK_WAITING_TEST_BUSY_PIN);
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}
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static inline void wait_us_yield_with_strobe(uint32_t us) {
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    writePinHigh(QMK_WAITING_TEST_YIELD_PIN);
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    chThdSleepMicroseconds(us);
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    writePinLow(QMK_WAITING_TEST_YIELD_PIN);
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}
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static const uint32_t waiting_values[] = {0, 1, 5, 10, 25, 50, 100, 150, 200, 500, 1000};
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void housekeeping_task_user(void) {
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    static uint32_t last_bench = 0;
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    if (timer_elapsed32(last_bench) > 500) {
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        for (int i = 0; i < (sizeof(waiting_values) / sizeof(waiting_values[0])); i++) {
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            wait_us_polling_with_strobe(waiting_values[i]);
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            wait_us(10);
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        }
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        for (int i = 0; i < (sizeof(waiting_values) / sizeof(waiting_values[0])); i++) {
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            wait_us_yield_with_strobe(waiting_values[i]);
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            wait_us(10);
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        }
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        last_bench = timer_read32();
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    }
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}
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