microbitv2: Refactory board id and Kl27 timer code into their own files.

This should result in no change in behaviour.

records/board/kl27z_microbit_bl.yaml

@@ -1,6 +1,8 @@
 common:
     macros:
         - MICROBIT_LOCK_BOOTLOADER
+    includes:
+        - source/board/microbitv2/board_id.h
     sources:
         board:
             - source/board/kl27z_microbit_bl.c

records/board/nrf52820_microbit_bl.yaml

@@ -1,4 +1,6 @@
 common:
+    includes:
+        - source/board/microbitv2/board_id.h
     sources:
         board:
             - source/board/nrf52820_microbit_bl.c

source/board/kl27z_microbit_bl.c

@@ -26,6 +26,7 @@
 #include "target_family.h"
 #include "fsl_device_registers.h"
 #include "gpio.h"
+#include "board_id.h"
 
 // Warning - changing the interface start will break backwards compatibility
 COMPILER_ASSERT(DAPLINK_ROM_IF_START == KB(32));
@@ -59,7 +60,7 @@ const target_family_descriptor_t *g_target_family = NULL;
 
 const board_info_t g_board_info = {
     .info_version = kBoardInfoVersion,
-    .board_id = "9903",
+    .board_id = BOARD_ID_MB_2_DEFAULT,
     .daplink_url_name =       "HELP_FAQHTM",
     .daplink_drive_name =       "MAINTENANCE",
     .daplink_target_url = "https://microbit.org/device/?id=@B&v=@V&bl=1",

source/board/microbitv2/board_id.h

@@ -0,0 +1,53 @@
+/**
+ * @file    board_id.h
+ * @brief
+ *
+ * DAPLink Interface Firmware
+ * Copyright 2021 Micro:bit Educational Foundation
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef BOARD_ID_H_
+#define BOARD_ID_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define BOARD_ID_MB_2_DEFAULT       "9903"
+#define BOARD_ID_MB_2_0             "9904"
+#define BOARD_ID_MB_2_2_833         "9905"
+#define BOARD_ID_MB_2_2_820         "9906"
+
+typedef enum {
+    BOARD_VERSION_2_DEF = 0x9903,
+    BOARD_VERSION_2_0 = 0x9904,
+    BOARD_VERSION_2_2_833 = 0x9905,
+    BOARD_VERSION_2_2_820 = 0x9906,
+} mb_version_t;
+
+
+/**
+ * Determines the micro:bit board ID based on on-board components configured
+ * differently between versions.
+ */
+mb_version_t board_id_detect(void);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* BOARD_ID_H_ */

source/board/microbitv2/kl27z/board_id.c

@@ -0,0 +1,95 @@
+/**
+ * @file    board_id.c
+ * @brief
+ *
+ * DAPLink Interface Firmware
+ * Copyright 2020 NXP
+ * Copyright 2021 Micro:bit Educational Foundation
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "IO_Config.h"
+
+#include "board_id.h"
+#include "timer_wait.h"
+
+#include "adc.h"
+#include "fsl_port.h"
+#include "fsl_gpio.h"
+
+#define BRD_ID_1_UPPER_THR_V        935   // Upper threshold in mV for 100nF and 4700R
+#define BRD_ID_1_LOWER_THR_V        268   // Lower threshold in mV for 100nF and 4700R
+
+// Board Rev ID detection. Reads BRD_REV_ID voltage
+// Depends on gpio_init() to have been executed already
+mb_version_t board_id_detect()
+{
+    gpio_pin_config_t pin_config = {
+        .pinDirection = kGPIO_DigitalOutput,
+        .outputLogic = 0U
+    };
+    uint32_t board_rev_id_adc = 0;
+    uint32_t board_rev_id_mv = 0;
+
+    // Set Board Rev ID pin as output but pin disabled
+    PORT_SetPinMux(PIN_BOARD_REV_ID_PORT , PIN_BOARD_REV_ID_BIT,  kPORT_PinDisabledOrAnalog);
+    PORT_SetPinDriveStrength(PIN_BOARD_REV_ID_PORT, PIN_BOARD_REV_ID_BIT, kPORT_HighDriveStrength);
+    GPIO_PinInit(PIN_BOARD_REV_ID_GPIO, PIN_BOARD_REV_ID_BIT, &pin_config);
+
+    adc_init();
+    timer_wait_init();
+
+    // 1. Discharge capacitor
+    /* Set timer period 3ms*/
+    timer_wait_set_period(3000);
+    /* Drive BRD_REV_ID pin to low */
+    GPIO_PortClear(PIN_BOARD_REV_ID_GPIO, PIN_BOARD_REV_ID);
+    PORT_SetPinMux(PIN_BOARD_REV_ID_PORT , PIN_BOARD_REV_ID_BIT,  kPORT_MuxAsGpio);
+    /* Wait 3ms to allow the 100nF Cap to discharge at least 5*RC with 4700R */
+    timer_wait();
+
+    // 2. Charge capacitor for 100us
+    /* Set timer period slightly below 100us to account for overheads */
+    timer_wait_set_period(98);
+    /* Drive BRD_REV_ID pin to high */
+    GPIO_PortSet(PIN_BOARD_REV_ID_GPIO, PIN_BOARD_REV_ID);
+    /* Wait for ~100us */
+    timer_wait();
+    /* Change pin to ADC (High-Z). Capacitor will stop charging */
+    PORT_SetPinMux(PIN_BOARD_REV_ID_PORT , PIN_BOARD_REV_ID_BIT,  kPORT_PinDisabledOrAnalog);
+
+    // 3. Take ADC measurement
+    board_rev_id_adc = adc_read_channel(0, PIN_BOARD_REV_ID_ADC_CH, PIN_BOARD_REV_ID_ADC_MUX);
+    board_rev_id_mv = board_rev_id_adc * 3300 / 0xFFF;  // Convert ADC 12-bit value to mV with 3.3V reference
+
+    // 4. Discharge capacitor
+    /* Set timer period 3ms */
+    timer_wait_set_period(3000);
+    /* Drive BRD_REV_ID pin to low */
+    GPIO_PortClear(PIN_BOARD_REV_ID_GPIO, PIN_BOARD_REV_ID);
+    PORT_SetPinMux(PIN_BOARD_REV_ID_PORT , PIN_BOARD_REV_ID_BIT,  kPORT_MuxAsGpio);
+    /* Wait 3ms to allow the 100nF Cap to discharge at least 5*RC with 4700R */
+    timer_wait();
+
+    // 5. Identify board ID depending on voltage
+    mb_version_t board_version;
+    if (board_rev_id_mv > BRD_ID_1_LOWER_THR_V && board_rev_id_mv < BRD_ID_1_UPPER_THR_V) {
+        board_version = BOARD_VERSION_2_0;
+    } else {
+        board_version = BOARD_VERSION_2_DEF;
+    }
+
+    return board_version;
+}

source/board/microbitv2/kl27z/pwr_mon.c

@@ -20,6 +20,8 @@
  */
 
 #include "pwr_mon.h"
+#include "timer_wait.h"
+
 #include "adc.h"
 #include "fsl_adc16.h"
 #include "fsl_pmc.h"
@@ -39,20 +41,17 @@ static void pwr_mon_bandgap_init(void);
 static uint32_t pwr_mon_read_vbg(uint32_t channelGroup);
 static uint32_t pwr_mon_adc_to_mv(uint32_t raw_adc);
 
-void TPM0_IRQHandler(void);
-
-extern volatile bool tpmIsrFlag;
-extern uint32_t tpm_source_clock;
 
 void pwr_mon_init(void)
 {
     gpio_pin_config_t pin_config = {
         .pinDirection = kGPIO_DigitalOutput,
         .outputLogic = 0U
     };
-    
+
     adc_init();
-
+    timer_wait_init();
+
     // Configure VMON_BAT and RUN_VBAT_SENSE
     GPIO_PinInit(PIN_RUN_VBAT_SENSE_GPIO, PIN_RUN_VBAT_SENSE_BIT, &pin_config);
     PORT_SetPinMux(PIN_RUN_VBAT_SENSE_PORT, PIN_RUN_VBAT_SENSE_BIT, kPORT_MuxAsGpio);
@@ -90,23 +89,22 @@ power_source_t pwr_mon_get_power_source(void) {
     return power_source;
 }
 
-uint32_t pwr_mon_get_vbat_mv(void) {
+uint32_t pwr_mon_get_vbat_mv(void)
+{
     /* Set timer period 3ms*/
-    TPM_SetTimerPeriod(TPM0, USEC_TO_COUNT(3000U, tpm_source_clock));
+    timer_wait_set_period(3000);
     // Enable voltage divider to take measurement
     GPIO_PinWrite(PIN_RUN_VBAT_SENSE_GPIO, PIN_RUN_VBAT_SENSE_BIT, 1);
     // Add a ~3ms delay to allow the 100nF capacitors to charge to about 3*RC.
-    TPM_StartTimer(TPM0, kTPM_SystemClock);
-    while (false == tpmIsrFlag);
-    tpmIsrFlag = false;
+    timer_wait();
 
     uint32_t bat_adc = adc_read_channel(0, PIN_VMON_BAT_ADC_CH, PIN_VMON_BAT_ADC_MUX);
     // Disable voltage divider
     GPIO_PinWrite(PIN_RUN_VBAT_SENSE_GPIO, PIN_RUN_VBAT_SENSE_BIT, 0);
-    
+
     // Compensate for voltage divider with ratio of 11
     bat_adc = bat_adc * 11;
-    
+
     return pwr_mon_adc_to_mv(bat_adc);
 }
 

source/board/microbitv2/kl27z/timer_wait.c

@@ -0,0 +1,70 @@
+/**
+ * @file    timer_wait.c
+ * @brief
+ *
+ * DAPLink Interface Firmware
+ * Copyright 2021 Micro:bit Educational Foundation
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "timer_wait.h"
+
+#include "fsl_device_registers.h"
+#include "fsl_tpm.h"
+
+
+static volatile bool tpmIsrFlag = false;
+static uint32_t tpm_source_clock;
+
+
+void TPM0_IRQHandler(void)
+{
+    /* Clear interrupt flag.*/
+    TPM_ClearStatusFlags(TPM0, kTPM_TimeOverflowFlag);
+    tpmIsrFlag = true;
+    TPM_StopTimer(TPM0);
+    __DSB();
+}
+
+void timer_wait_init(void)
+{
+    /* Select the clock source for the TPM counter as kCLOCK_McgIrc48MClk */
+    CLOCK_SetTpmClock(1U);
+
+    tpm_config_t tpmInfo;
+    TPM_GetDefaultConfig(&tpmInfo);
+    /* TPM clock divide by TPM_PRESCALER */
+    tpmInfo.prescale = kTPM_Prescale_Divide_4;
+    /* Initialize TPM module */
+    TPM_Init(TPM0, &tpmInfo);
+
+    TPM_EnableInterrupts(TPM0, kTPM_TimeOverflowInterruptEnable);
+    EnableIRQ(TPM0_IRQn);
+
+    tpm_source_clock = (CLOCK_GetFreq(kCLOCK_McgIrc48MClk) / 4);
+    tpmIsrFlag = false;
+}
+
+void timer_wait_set_period(uint32_t microsec)
+{
+    TPM_SetTimerPeriod(TPM0, USEC_TO_COUNT(microsec, tpm_source_clock));
+}
+
+void timer_wait(void)
+{
+    TPM_StartTimer(TPM0, kTPM_SystemClock);
+    while (false == tpmIsrFlag);
+    tpmIsrFlag = false;
+}

source/board/microbitv2/kl27z/timer_wait.h

@@ -0,0 +1,33 @@
+/**
+ * @file    timer_wait.h
+ * @brief
+ *
+ * DAPLink Interface Firmware
+ * Copyright 2021 Micro:bit Educational Foundation
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TIMER_WAIT_H_
+#define TIMER_WAIT_H_
+
+#include <stdint.h>
+
+
+void timer_wait_init(void);
+void timer_wait_set_period(uint32_t microsec);
+void timer_wait(void);
+
+
+#endif /* TIMER_WAIT_H_ */