~ruther/qmk_firmware

3f5dc472965e6a5b8efe60e33c7b6c2d18d92008 — Stefan Kerkmann 3 years ago 57021d6
[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
M keyboards/handwired/onekey/elite_c/config.h => keyboards/handwired/onekey/elite_c/config.h +3 -0
@@ 30,3 30,6 @@
#define RGB_CI_PIN B1

#define ADC_PIN F6

#define QMK_WAITING_TEST_BUSY_PIN F6
#define QMK_WAITING_TEST_YIELD_PIN F7

A keyboards/handwired/onekey/keymaps/chibios_waiting_test/config.h => keyboards/handwired/onekey/keymaps/chibios_waiting_test/config.h +12 -0
@@ 0,0 1,12 @@
// Copyright 2022 Stefan Kerkmann
// SPDX-License-Identifier: GPL-2.0-or-later

#pragma once

#if !defined(QMK_WAITING_TEST_BUSY_PIN)
#    define QMK_WAITING_TEST_BUSY_PIN A8
#endif

#if !defined(QMK_WAITING_TEST_YIELD_PIN)
#    define QMK_WAITING_TEST_YIELD_PIN A9
#endif

A keyboards/handwired/onekey/keymaps/chibios_waiting_test/keymap.c => keyboards/handwired/onekey/keymaps/chibios_waiting_test/keymap.c +47 -0
@@ 0,0 1,47 @@
// Copyright 2022 Stefan Kerkmann
// SPDX-License-Identifier: GPL-2.0-or-later

#include QMK_KEYBOARD_H

const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {LAYOUT_ortho_1x1(KC_A)};

#if defined(__AVR__)
#    pragma message "AVR uses polled waiting by default, running theses tests will not show any difference"
static inline void chThdSleepMicroseconds(uint32_t us) {
    wait_us(us);
}
#endif

void keyboard_post_init_user(void) {
    setPinOutput(QMK_WAITING_TEST_BUSY_PIN);
    setPinOutput(QMK_WAITING_TEST_YIELD_PIN);
}

static inline void wait_us_polling_with_strobe(uint32_t us) {
    writePinHigh(QMK_WAITING_TEST_BUSY_PIN);
    wait_us(us);
    writePinLow(QMK_WAITING_TEST_BUSY_PIN);
}

static inline void wait_us_yield_with_strobe(uint32_t us) {
    writePinHigh(QMK_WAITING_TEST_YIELD_PIN);
    chThdSleepMicroseconds(us);
    writePinLow(QMK_WAITING_TEST_YIELD_PIN);
}

static const uint32_t waiting_values[] = {0, 1, 5, 10, 25, 50, 100, 150, 200, 500, 1000};

void housekeeping_task_user(void) {
    static uint32_t last_bench = 0;
    if (timer_elapsed32(last_bench) > 500) {
        for (int i = 0; i < (sizeof(waiting_values) / sizeof(waiting_values[0])); i++) {
            wait_us_polling_with_strobe(waiting_values[i]);
            wait_us(10);
        }
        for (int i = 0; i < (sizeof(waiting_values) / sizeof(waiting_values[0])); i++) {
            wait_us_yield_with_strobe(waiting_values[i]);
            wait_us(10);
        }
        last_bench = timer_read32();
    }
}

M keyboards/handwired/onekey/promicro/config.h => keyboards/handwired/onekey/promicro/config.h +3 -0
@@ 30,3 30,6 @@
#define RGB_CI_PIN B1

#define ADC_PIN F6

#define QMK_WAITING_TEST_BUSY_PIN F6
#define QMK_WAITING_TEST_YIELD_PIN F7

M keyboards/handwired/onekey/rp2040/config.h => keyboards/handwired/onekey/rp2040/config.h +7 -2
@@ 6,10 6,15 @@
#include "config_common.h"

#define PRODUCT Onekey Raspberry Pi RP2040
#define MATRIX_COL_PINS { GP4 }
#define MATRIX_ROW_PINS { GP5 }
#define MATRIX_COL_PINS \
    { GP4 }
#define MATRIX_ROW_PINS \
    { GP5 }
#define DEBUG_MATRIX_SCAN_RATE

#define QMK_WAITING_TEST_BUSY_PIN GP8
#define QMK_WAITING_TEST_YIELD_PIN GP9

#define RP2040_BOOTLOADER_DOUBLE_TAP_RESET
#define RP2040_BOOTLOADER_DOUBLE_TAP_RESET_LED GP25
#define RP2040_BOOTLOADER_DOUBLE_TAP_RESET_TIMEOUT 500U

M keyboards/handwired/onekey/teensy_2/config.h => keyboards/handwired/onekey/teensy_2/config.h +3 -0
@@ 29,3 29,6 @@
#define RGB_DI_PIN F6

#define ADC_PIN F6

#define QMK_WAITING_TEST_BUSY_PIN F6
#define QMK_WAITING_TEST_YIELD_PIN F7

M keyboards/handwired/onekey/teensy_2pp/config.h => keyboards/handwired/onekey/teensy_2pp/config.h +3 -0
@@ 29,3 29,6 @@
#define RGB_DI_PIN F6

#define ADC_PIN F6

#define QMK_WAITING_TEST_BUSY_PIN F6
#define QMK_WAITING_TEST_YIELD_PIN F7

M keyboards/planck/rev6_drop/matrix.c => keyboards/planck/rev6_drop/matrix.c +13 -12
@@ 15,14 15,7 @@
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include "hal.h"
#include "timer.h"
#include "wait.h"
#include "debug.h"
#include "matrix.h"
#include "quantum.h"

/*
 *     col: { B11, B10, B2, B1, A7, B0 }


@@ 38,9 31,13 @@ __attribute__((weak)) void matrix_init_user(void) {}

__attribute__((weak)) void matrix_scan_user(void) {}

__attribute__((weak)) void matrix_init_kb(void) { matrix_init_user(); }
__attribute__((weak)) void matrix_init_kb(void) {
    matrix_init_user();
}

__attribute__((weak)) void matrix_scan_kb(void) { matrix_scan_user(); }
__attribute__((weak)) void matrix_scan_kb(void) {
    matrix_scan_user();
}

void matrix_init(void) {
    dprintf("matrix init\n");


@@ 146,9 143,13 @@ uint8_t matrix_scan(void) {
    return 1;
}

bool matrix_is_on(uint8_t row, uint8_t col) { return (matrix[row] & (1 << col)); }
bool matrix_is_on(uint8_t row, uint8_t col) {
    return (matrix[row] & (1 << col));
}

matrix_row_t matrix_get_row(uint8_t row) { return matrix[row]; }
matrix_row_t matrix_get_row(uint8_t row) {
    return matrix[row];
}

void matrix_print(void) {
    dprintf("\nr/c 01234567\n");

M keyboards/preonic/rev3_drop/matrix.c => keyboards/preonic/rev3_drop/matrix.c +13 -12
@@ 15,14 15,7 @@
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include "hal.h"
#include "timer.h"
#include "wait.h"
#include "debug.h"
#include "matrix.h"
#include "quantum.h"

typedef uint16_t matrix_col_t;



@@ 40,9 33,13 @@ __attribute__((weak)) void matrix_init_user(void) {}

__attribute__((weak)) void matrix_scan_user(void) {}

__attribute__((weak)) void matrix_init_kb(void) { matrix_init_user(); }
__attribute__((weak)) void matrix_init_kb(void) {
    matrix_init_user();
}

__attribute__((weak)) void matrix_scan_kb(void) { matrix_scan_user(); }
__attribute__((weak)) void matrix_scan_kb(void) {
    matrix_scan_user();
}

void matrix_init(void) {
    dprintf("matrix init\n");


@@ 150,9 147,13 @@ uint8_t matrix_scan(void) {
    return 1;
}

bool matrix_is_on(uint8_t row, uint8_t col) { return (matrix[row] & (1 << col)); }
bool matrix_is_on(uint8_t row, uint8_t col) {
    return (matrix[row] & (1 << col));
}

matrix_row_t matrix_get_row(uint8_t row) { return matrix[row]; }
matrix_row_t matrix_get_row(uint8_t row) {
    return matrix[row];
}

void matrix_print(void) {
    dprintf("\nr/c 01234567\n");

M platforms/chibios/_wait.h => platforms/chibios/_wait.h +5 -0
@@ 30,6 30,11 @@

#ifdef WAIT_US_TIMER
void wait_us(uint16_t duration);
#elif PORT_SUPPORTS_RT == TRUE
#    define wait_us(us)                                            \
        do {                                                       \
            chSysPolledDelayX(US2RTC(REALTIME_COUNTER_CLOCK, us)); \
        } while (0)
#else
#    define wait_us(us)                     \
        do {                                \

M platforms/chibios/bootloaders/rp2040.c => platforms/chibios/bootloaders/rp2040.c +2 -3
@@ 43,9 43,8 @@ void __late_init(void) {
    if (magic_location != magic_token) {
        magic_location = magic_token;
        // ChibiOS is not initialized at this point, so sleeping is only
        // possible via busy waiting. The internal timer peripheral is running
        // at this point with a precision of 1us.
        chSysPolledDelayX(MS2RTC(1 * MHZ, RP2040_BOOTLOADER_DOUBLE_TAP_RESET_TIMEOUT));
        // possible via busy waiting.
        wait_us(RP2040_BOOTLOADER_DOUBLE_TAP_RESET_TIMEOUT * 1000U);
        magic_location = 0;
        return;
    }

M platforms/chibios/chibios_config.h => platforms/chibios/chibios_config.h +12 -0
@@ 21,6 21,9 @@

#if defined(MCU_RP)
#    define CPU_CLOCK RP_CORE_CLK
// ChibiOS uses the RP2040 timer peripheral as its real time counter, this timer
// is monotonic and running at 1MHz.
#    define REALTIME_COUNTER_CLOCK 1000000

#    define USE_GPIOV1
#    define PAL_OUTPUT_TYPE_OPENDRAIN _Static_assert(0, "RP2040 has no Open Drain GPIO configuration, setting this is not possible");


@@ 102,6 105,11 @@
#    endif
#endif

#if defined(MCU_MIMXRT1062)
#    include "clock_config.h"
#    define CPU_CLOCK BOARD_BOOTCLOCKRUN_CORE_CLOCK
#endif

#if defined(HT32)
#    define CPU_CLOCK HT32_CK_SYS_FREQUENCY
#    define PAL_MODE_ALTERNATE PAL_HT32_MODE_AF


@@ 109,3 117,7 @@
#    define PAL_OUTPUT_TYPE_PUSHPULL PAL_HT32_MODE_DIR
#    define PAL_OUTPUT_SPEED_HIGHEST 0
#endif

#if !defined(REALTIME_COUNTER_CLOCK)
#    define REALTIME_COUNTER_CLOCK CPU_CLOCK
#endif

M platforms/chibios/drivers/serial.c => platforms/chibios/drivers/serial.c +2 -1
@@ 20,7 20,8 @@
#    error "chSysPolledDelayX method not supported on this platform"
#else
#    undef wait_us
#    define wait_us(x) chSysPolledDelayX(US2RTC(CPU_CLOCK, x))
// Force usage of polled waiting - in case WAIT_US_TIMER is activated
#    define wait_us(us) chSysPolledDelayX(US2RTC(REALTIME_COUNTER_CLOCK, us))
#endif

#ifndef SELECT_SOFT_SERIAL_SPEED

M platforms/chibios/drivers/vendor/RP/RP2040/serial_vendor.c => platforms/chibios/drivers/vendor/RP/RP2040/serial_vendor.c +1 -1
@@ 152,7 152,7 @@ static inline void enter_rx_state(void) {
    }
    // Wait for ~11 bits, 1 start bit + 8 data bits + 1 stop bit + 1 bit
    // headroom.
    chSysPolledDelayX(US2RTC(1 * MHZ, (1000000U * 11 / SERIAL_USART_SPEED)));
    wait_us(1000000U * 11U / SERIAL_USART_SPEED);
    // Disable tx state machine to not interfere with our tx pin manipulation
    pio_sm_set_enabled(pio, tx_state_machine, false);
    gpio_set_drive_strength(SERIAL_USART_TX_PIN, GPIO_DRIVE_STRENGTH_2MA);