AP_HAL_ChibiOS: order PWM timers by DMA UP stream id to prevent deadlocks in dshot

libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py

@@ -1362,14 +1362,15 @@ def parse_timer(str):
         error("Bad timer definition %s" % str)
 
 
-def write_PWM_config(f):
+def write_PWM_config(f, ordered_timers):
     '''write PWM config defines'''
     rc_in = None
     rc_in_int = None
     alarm = None
     bidir = None
     pwm_out = []
-    pwm_timers = []
+    # start with the ordered list from the dma resolver
+    pwm_timers = ordered_timers
     has_bidir = False
     for l in bylabel.keys():
         p = bylabel[l]
@@ -1388,6 +1389,7 @@ def write_PWM_config(f):
                 if p.type not in pwm_timers:
                     pwm_timers.append(p.type)
 
+
     f.write('#define HAL_PWM_COUNT %u\n' % len(pwm_out))
     if not pwm_out and not alarm:
         print("No PWM output defined")
@@ -1471,7 +1473,7 @@ def write_PWM_config(f):
     f.write('// PWM timer config\n')
     if bidir is not None:
         f.write('#define HAL_WITH_BIDIR_DSHOT\n')
-    for t in sorted(pwm_timers):
+    for t in pwm_timers:
         n = int(t[3:])
         f.write('#define STM32_PWM_USE_TIM%u TRUE\n' % n)
         f.write('#define STM32_TIM%u_SUPPRESS_ISR\n' % n)
@@ -1479,7 +1481,8 @@ def write_PWM_config(f):
     f.write('// PWM output config\n')
     groups = []
     have_complementary = False
-    for t in sorted(pwm_timers):
+
+    for t in pwm_timers:
         group = len(groups) + 1
         n = int(t[3:])
         chan_list = [255, 255, 255, 255]
@@ -1761,13 +1764,13 @@ def write_hwdef_header(outfilename):
 
     write_peripheral_enable(f)
 
-    dma_unassigned = dma_resolver.write_dma_header(f, periph_list, mcu_type,
+    dma_unassigned, ordered_timers = dma_resolver.write_dma_header(f, periph_list, mcu_type,
                                                    dma_exclude=get_dma_exclude(periph_list),
                                                    dma_priority=get_config('DMA_PRIORITY', default='TIM* SPI*', spaces=True),
                                                    dma_noshare=get_config('DMA_NOSHARE', default='', spaces=True))
 
     if not args.bootloader:
-        write_PWM_config(f)
+        write_PWM_config(f, ordered_timers)
         write_I2C_config(f)
         write_UART_config(f)
     else:

libraries/AP_HAL_ChibiOS/hwdef/scripts/dma_resolver.py

@@ -346,6 +346,23 @@ def write_dma_header(f, peripheral_list, mcu_type, dma_exclude=[],
             "\n// Note: The following peripherals can't be resolved for DMA: %s\n\n"
             % unassigned)
 
+    ordered_up_channels = []
+
+    # produce a list of timers ordered by the DMA streamid of the UP channel
+    # this is so that the dshot code can take out the UP DMA locks in the same order as I2C and SPI
+    for key in curr_dict.keys():
+        if "_UP" in key:
+            ordered_up_channels.append(key)
+
+    def order_by_streamid(key):
+        stream = curr_dict[key]
+        return (stream[0] * 8 + stream[1]) * 20 + int(key[3:-3])
+
+    ordered_up_channels = sorted(ordered_up_channels, key=order_by_streamid)
+    ordered_timers = []
+    for key in ordered_up_channels:
+        ordered_timers.append(key[0:-3])
+
     for key in sorted(curr_dict.keys()):
         stream = curr_dict[key]
         shared = ''
@@ -435,7 +452,7 @@ def write_dma_header(f, peripheral_list, mcu_type, dma_exclude=[],
             continue
         f.write('#define STM32_SPI_%s_DMA_STREAMS STM32_SPI_%s_TX_%s_STREAM, STM32_SPI_%s_RX_%s_STREAM\n' % (
             key, key, dma_name(key), key, dma_name(key)))
-    return unassigned
+    return unassigned, ordered_timers
 
 
 if __name__ == '__main__':