stm32f0: Various fixes according to comment: (#1453)

* Copyright in log.c
* GPIO check completely removed
* generic/timer_irq added
* Change in doc section

Signed-off-by: Eugene Krashtan <eug.krashtan@gmail.com>

docs/stm32f0_CAN.md

@@ -7,6 +7,8 @@ Required components
 #### MCP2515 module
 
 ![MCP2515](img/mcp2515.jpg)
+or this
+![CAN/RS485 hat](img/canhat.jpg)
 
 #### St-link dongle
 
@@ -17,7 +19,7 @@ Adding CAN bus to Raspberry Pi
 ==============================
 (Based on Quick Guide https://www.raspberrypi.org/forums/viewtopic.php?f=44&t=141052)
 
-First of all, it’s necessary to modify the CAN-module from ebay, because it has
+First of all, (only if you have small CAN module) it’s necessary to modify the CAN-module from ebay, because it has
 only one VCC pin, but the MCP2515 needs to be powered from 3V3 and the TJA1050
 CAN-transceiver needs to be powered from 5V. Powering both chips from 5V would
 work, but then a level-shifter for the SPI would be needed. The Pi's GPIO pins
@@ -135,5 +137,6 @@ Now "make flash" command can upload HEX into connected board
 Pins allocation
 ===============
 
-Configurations with CAN and Serial port uses different pins, and firmware contains only
+Configurations with CAN and Serial port uses different pins, and during enumeration
-actual pins initialization.
+process firmware reports all possible pin names. But actually you can use only
+existing pins, not involved in communication. Wrong pins will generate shutdown.

src/stm32f0/Makefile

@@ -25,6 +25,7 @@ src-$(CONFIG_CANSERIAL) += stm32f0/can.c
 src-$(CONFIG_DEBUG_OUT) += stm32f0/log.c
 src-$(CONFIG_SERIAL) += stm32f0/serial.c
 src-y += generic/serial_irq.c
+src-y += generic/timer_irq.c
 src-$(CONFIG_HAVE_GPIO_ADC) += stm32f0/adc.c
 src-$(CONFIG_HAVE_GPIO_I2C) += stm32f0/i2c.c
 src-$(CONFIG_HAVE_GPIO_SPI) += stm32f0/spi.c

src/stm32f0/gpio.c

@@ -51,7 +51,6 @@ uint8_t const avail_pins[] = {
 static uint8_t
 gpio_check_pin(uint8_t pin)
 {
-    gpio_check_busy(pin);
     int i;
     for(i=0; i<ARRAY_SIZE(avail_pins); i++) {
         if (avail_pins[i] == pin)
@@ -140,22 +139,3 @@ void gpio_init(void)
     __HAL_RCC_GPIOB_CLK_ENABLE();
     __HAL_RCC_GPIOF_CLK_ENABLE();
 }
-
-void gpio_check_busy(uint8_t pin)
-{
-    // Increase to uint32_t and assert <32 on bigger chips
-    static uint16_t pinmap;
-    assert_param(sizeof(avail_pins)<16);
-
-    for (int i = 0; i<sizeof(avail_pins); i++) {
-        if(avail_pins[i]==pin) {
-            if(pinmap&(1<<i)) {
-                break;
-            } else {
-                pinmap |= 1<<i;
-                return;
-            }
-        }
-    }
-    shutdown("GPIO check failed");
-}

src/stm32f0/i2c.c

@@ -11,6 +11,7 @@
 #include "board/gpio.h" // i2c_setup
 #include "sched.h" // sched_shutdown
 #include "command.h" // shutdown
+#include "board/misc.h" // timer_is_before
 
 I2C_HandleTypeDef hi2c1;
 
@@ -21,9 +22,6 @@ struct i2c_config i2c_setup(uint32_t bus, uint32_t rate, uint8_t addr)
     PF0-OSC_IN     ------> I2C1_SDA
     PF1-OSC_OUT     ------> I2C1_SCL
     */
-    gpio_check_busy(0x30); //PF0
-    gpio_check_busy(0x31); //PF1
-
     GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1;
     GPIO_InitStruct.Mode = GPIO_MODE_AF_OD;
     GPIO_InitStruct.Pull = GPIO_PULLUP;
@@ -50,19 +48,29 @@ struct i2c_config i2c_setup(uint32_t bus, uint32_t rate, uint8_t addr)
     return (struct i2c_config){ .addr = addr };
 }
 
+static void
+i2c_to_check(uint32_t timeout)
+{
+    if (!timer_is_before(timer_read_time(), timeout))
+        shutdown("i2c timeout");
+}
+
 void i2c_write(struct i2c_config config, uint8_t write_len, uint8_t *write)
 {
+    uint32_t timeout = timer_read_time() + timer_from_us(5000);
     while(HAL_I2C_Master_Transmit(&hi2c1, config.addr, write,
             (uint16_t)write_len, (uint32_t)1000)!= HAL_OK) {
          if (HAL_I2C_GetError(&hi2c1) != HAL_I2C_ERROR_AF) {
              shutdown("Buffer error");
          }
+         i2c_to_check(timeout);
      }
 }
 
 void i2c_read(struct i2c_config config, uint8_t reg_len, uint8_t *reg
               , uint8_t read_len, uint8_t *read)
 {
+    uint32_t timeout = timer_read_time() + timer_from_us(5000);
     i2c_write(config, reg_len, reg);
     while(HAL_I2C_Master_Receive(&hi2c1, config.addr, read,
             (uint16_t)read_len, (uint32_t)1000)!= HAL_OK) {
@@ -70,6 +78,7 @@ void i2c_read(struct i2c_config config, uint8_t reg_len, uint8_t *reg
              shutdown("Buffer error");
          }
      }
+    i2c_to_check(timeout);
 }
 
 /**

src/stm32f0/log.c

@@ -3,8 +3,8 @@
  * This file not required for regular Klipper usage, but hw/sw developer
  * can use USART TX pin instead SWO for debugging purposes
  *
- *  Created on: Jan 17, 2019
+ *  Copyright (C) 2019 Eug Krashtan <eug.krashtan@gmail.com>
- *      Author: eug
+ *  This file may be distributed under the terms of the GNU GPLv3 license.
  */
 
 #include "string.h"

src/stm32f0/spi.c

@@ -13,8 +13,6 @@
 #include "sched.h" // sched_shutdown
 #include "log.h"
 
-//static SPI_HandleTypeDef hspi1;
-
 void spi_hw_setup(uint32_t rate)
 {
     GPIO_InitTypeDef GPIO_InitStruct = {0};
@@ -28,9 +26,6 @@ void spi_hw_setup(uint32_t rate)
     PA6     ------> SPI1_MISO
     PA7     ------> SPI1_MOSI
     */
-    gpio_check_busy(0x05); //PA5
-    gpio_check_busy(0x06); //PA6
-    gpio_check_busy(0x07); //PA7
     GPIO_InitStruct.Pin = GPIO_PIN_5|GPIO_PIN_6|GPIO_PIN_7;
     GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
     GPIO_InitStruct.Pull = GPIO_NOPULL;
@@ -52,22 +47,6 @@ void spi_hw_setup(uint32_t rate)
             SPI_RXFIFO_THRESHOLD_QF;
 
     SPI1->CR1 |= SPI_CR1_SPE; // Enable
-
-    //hspi1.Instance = SPI1;
-    //hspi1.Init.Mode = SPI_MODE_MASTER;
-    //hspi1.Init.Direction = SPI_DIRECTION_2LINES;
-    //hspi1.Init.DataSize = SPI_DATASIZE_8BIT;
-    //hspi1.Init.CLKPolarity = SPI_POLARITY_LOW;
-    //hspi1.Init.CLKPhase = SPI_PHASE_1EDGE;
-    //hspi1.Init.NSS = SPI_NSS_SOFT;
-    //hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_4;
-    //hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
-    //hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
-    //hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
-    //hspi1.Init.CRCPolynomial = 7;
-    //hspi1.Init.CRCLength = SPI_CRC_LENGTH_DATASIZE;
-    //hspi1.Init.NSSPMode = SPI_NSS_PULSE_DISABLE;
-    //HAL_SPI_Init(&hspi1);
 }
 
 struct spi_config

src/stm32f0/timer.c

@@ -16,30 +16,13 @@
 #include "log.h"
 #include "sched.h" // DECL_INIT
 #include "command.h" // shutdown
-
+#include "board/timer_irq.h" // timer_dispatch_many
-DECL_CONSTANT("CLOCK_FREQ", CONFIG_CLOCK_FREQ);
-
-// Return the number of clock ticks for a given number of microseconds
-uint32_t
-timer_from_us(uint32_t us)
-{
-    return us * (CONFIG_CLOCK_FREQ / 1000000);
-}
-
-// Return true if time1 is before time2.  Always use this function to
-// compare times as regular C comparisons can fail if the counter
-// rolls over.
-uint8_t
-timer_is_before(uint32_t time1, uint32_t time2)
-{
-    return (int32_t)(time1 - time2) < 0;
-}
 
 // Set the next irq time
 static void
 timer_set_diff(uint32_t value)
 {
-    SysTick->LOAD = value;
+    SysTick->LOAD = value & SysTick_LOAD_RELOAD_Msk;
     SysTick->VAL = 0;
     SysTick->LOAD = 0;
 }
@@ -84,70 +67,16 @@ timer_read_time(void)
     return TIM2->CNT;
 }
 
-static uint32_t timer_repeat_until;
-#define TIMER_IDLE_REPEAT_TICKS timer_from_us(500)
-#define TIMER_REPEAT_TICKS timer_from_us(100)
-
-#define TIMER_MIN_TRY_TICKS timer_from_us(2)
-#define TIMER_DEFER_REPEAT_TICKS timer_from_us(5)
-
-// Invoke timers
-static uint32_t
-timer_dispatch_many(void)
-{
-    uint32_t tru = timer_repeat_until;
-    for (;;) {
-        // Run the next software timer
-        uint32_t next = sched_timer_dispatch();
-
-        uint32_t now = timer_read_time();
-        int32_t diff = next - now;
-        if (diff > (int32_t)TIMER_MIN_TRY_TICKS)
-            // Schedule next timer normally.
-            return diff;
-
-        if (unlikely(timer_is_before(tru, now))) {
-            // Check if there are too many repeat timers
-            if (diff < (int32_t)(-timer_from_us(1000)))
-                try_shutdown("Rescheduled timer in the past");
-            if (sched_tasks_busy()) {
-                timer_repeat_until = now + TIMER_REPEAT_TICKS;
-                return TIMER_DEFER_REPEAT_TICKS;
-            }
-            timer_repeat_until = tru = now + TIMER_IDLE_REPEAT_TICKS;
-        }
-
-        // Next timer in the past or near future - wait for it to be ready
-        irq_enable();
-        while (unlikely(diff > 0))
-            diff = next - timer_read_time();
-        irq_disable();
-    }
-}
-
 // IRQ handler
 void __visible __aligned(16) // aligning helps stabilize perf benchmarks
 SysTick_Handler(void)
 {
     irq_disable();
-    uint32_t diff = timer_dispatch_many();
+    uint32_t next = timer_dispatch_many();
-    timer_set_diff(diff);
+    timer_set_diff(next-timer_read_time());
     irq_enable();
 }
 
-// Make sure timer_repeat_until doesn't wrap 32bit comparisons
-void
-timer_task(void)
-{
-    uint32_t now = timer_read_time();
-    irq_disable();
-    if (timer_is_before(timer_repeat_until, now))
-        timer_repeat_until = now;
-    irq_enable();
-}
-DECL_TASK(timer_task);
-
-
 void TIM2_IRQHandler(void)
 {
     if(TIM2->SR & TIM_SR_UIF) {