samples: drivers: subsys: Don't use SW ISR table

bjarki-andreasen · bjarki-andreasen · commit db157bd4503b · 2025-10-10T11:57:54.000+02:00
The software ISR table is not required if multithreading is not
used, and no argument is passed to the irq handlers.

Update all drivers, samples and subsystems to not use the SW ISR
table and exclude it from the build. This saves approximately
2K ROM for all builds.

Signed-off-by: Bjarki Arge Andreasen &lt;bjarki.andreasen@nordicsemi.no&gt;
diff --git a/applications/installer/prj.conf b/applications/installer/prj.conf
@@ -5,6 +5,7 @@ CONFIG_IMG_MANAGER=y
 CONFIG_CRC=y
 CONFIG_REBOOT=y
 CONFIG_MULTITHREADING=n
+CONFIG_GEN_SW_ISR_TABLE=n
 CONFIG_USE_DT_CODE_PARTITION=y
 CONFIG_MAIN_STACK_SIZE=8192
 
diff --git a/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l05_cpuapp_s115_softdevice_defconfig b/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l05_cpuapp_s115_softdevice_defconfig
@@ -36,6 +36,9 @@ CONFIG_PARTITION_MANAGER_ENABLED=n
 CONFIG_MULTITHREADING=n
 CONFIG_ZERO_LATENCY_IRQS=y
 
+# Disable generation of the redundant SW ISR table
+CONFIG_GEN_SW_ISR_TABLE=n
+
 # Allow FLASH writes
 CONFIG_MPU_ALLOW_FLASH_WRITE=y
 
diff --git a/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l05_cpuapp_s115_softdevice_mcuboot_defconfig b/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l05_cpuapp_s115_softdevice_mcuboot_defconfig
@@ -36,6 +36,9 @@ CONFIG_PARTITION_MANAGER_ENABLED=n
 CONFIG_MULTITHREADING=n
 CONFIG_ZERO_LATENCY_IRQS=y
 
+# Disable generation of the redundant SW ISR table
+CONFIG_GEN_SW_ISR_TABLE=n
+
 # Allow FLASH writes
 CONFIG_MPU_ALLOW_FLASH_WRITE=y
 
diff --git a/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l10_cpuapp_s115_softdevice_defconfig b/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l10_cpuapp_s115_softdevice_defconfig
@@ -36,6 +36,9 @@ CONFIG_PARTITION_MANAGER_ENABLED=n
 CONFIG_MULTITHREADING=n
 CONFIG_ZERO_LATENCY_IRQS=y
 
+# Disable generation of the redundant SW ISR table
+CONFIG_GEN_SW_ISR_TABLE=n
+
 # Allow FLASH writes
 CONFIG_MPU_ALLOW_FLASH_WRITE=y
 
diff --git a/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l10_cpuapp_s115_softdevice_mcuboot_defconfig b/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l10_cpuapp_s115_softdevice_mcuboot_defconfig
@@ -36,6 +36,9 @@ CONFIG_PARTITION_MANAGER_ENABLED=n
 CONFIG_MULTITHREADING=n
 CONFIG_ZERO_LATENCY_IRQS=y
 
+# Disable generation of the redundant SW ISR table
+CONFIG_GEN_SW_ISR_TABLE=n
+
 # Allow FLASH writes
 CONFIG_MPU_ALLOW_FLASH_WRITE=y
 
diff --git a/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l15_cpuapp_s115_softdevice_defconfig b/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l15_cpuapp_s115_softdevice_defconfig
@@ -36,6 +36,9 @@ CONFIG_PARTITION_MANAGER_ENABLED=n
 CONFIG_MULTITHREADING=n
 CONFIG_ZERO_LATENCY_IRQS=y
 
+# Disable generation of the redundant SW ISR table
+CONFIG_GEN_SW_ISR_TABLE=n
+
 # Allow FLASH writes
 CONFIG_MPU_ALLOW_FLASH_WRITE=y
 
diff --git a/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l15_cpuapp_s115_softdevice_mcuboot_defconfig b/boards/nordic/bm_nrf54l15dk/bm_nrf54l15dk_nrf54l15_cpuapp_s115_softdevice_mcuboot_defconfig
@@ -36,6 +36,9 @@ CONFIG_PARTITION_MANAGER_ENABLED=n
 CONFIG_MULTITHREADING=n
 CONFIG_ZERO_LATENCY_IRQS=y
 
+# Disable generation of the redundant SW ISR table
+CONFIG_GEN_SW_ISR_TABLE=n
+
 # Allow FLASH writes
 CONFIG_MPU_ALLOW_FLASH_WRITE=y
 
diff --git a/drivers/console/console_bm_uarte.c b/drivers/console/console_bm_uarte.c
@@ -13,6 +13,12 @@
 
 static const nrfx_uarte_t uarte_inst = NRFX_UARTE_INSTANCE(BOARD_CONSOLE_UARTE_INST);
 
+ISR_DIRECT_DECLARE(console_bm_uarte_direct_isr)
+{
+	NRFX_UARTE_INST_HANDLER_GET(BOARD_CONSOLE_UARTE_INST)();
+	return 0;
+}
+
 static int uarte_init(void)
 {
 	int err;
@@ -33,10 +39,9 @@ static int uarte_init(void)
 	uarte_config.interrupt_priority = CONFIG_BM_UARTE_CONSOLE_UARTE_IRQ_PRIO;
 
 	/** We need to connect the IRQ ourselves. */
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(
-		NRF_UARTE_INST_GET(BOARD_CONSOLE_UARTE_INST)),
-		CONFIG_BM_UARTE_CONSOLE_UARTE_IRQ_PRIO,
-		NRFX_UARTE_INST_HANDLER_GET(BOARD_CONSOLE_UARTE_INST), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_CONSOLE_UARTE_INST)),
+			   CONFIG_BM_UARTE_CONSOLE_UARTE_IRQ_PRIO,
+			   console_bm_uarte_direct_isr, 0);
 
 	irq_enable(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_CONSOLE_UARTE_INST)));
 
diff --git a/lib/bm_buttons/bm_buttons.c b/lib/bm_buttons/bm_buttons.c
@@ -90,6 +90,26 @@ static void gpiote_uninit(void)
 #endif
 }
 
+#if defined(CONFIG_SOC_SERIES_NRF52X)
+ISR_DIRECT_DECLARE(gpiote_0_direct_isr)
+{
+	NRFX_GPIOTE_INST_HANDLER_GET(0)();
+	return 0;
+}
+#elif defined(CONFIG_SOC_SERIES_NRF54LX)
+ISR_DIRECT_DECLARE(gpiote_20_direct_isr)
+{
+	NRFX_GPIOTE_INST_HANDLER_GET(20)();
+	return 0;
+}
+
+ISR_DIRECT_DECLARE(gpiote_30_direct_isr)
+{
+	NRFX_GPIOTE_INST_HANDLER_GET(30)();
+	return 0;
+}
+#endif
+
 static int gpiote_init(void)
 {
 	int err;
@@ -102,8 +122,8 @@ static int gpiote_init(void)
 			return -EIO;
 		}
 
-		IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(0)), IRQ_PRIO,
-			    NRFX_GPIOTE_INST_HANDLER_GET(0), 0, 0);
+		IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(0)),
+				   IRQ_PRIO, gpiote_0_direct_isr, 0);
 	}
 #elif defined(CONFIG_SOC_SERIES_NRF54LX)
 	if (!nrfx_gpiote_init_check(&gpiote20_instance)) {
@@ -113,8 +133,9 @@ static int gpiote_init(void)
 			return -EIO;
 		}
 
-		IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(20)) + NRF_GPIOTE_IRQ_GROUP,
-			    IRQ_PRIO, NRFX_GPIOTE_INST_HANDLER_GET(20), 0, 0);
+		IRQ_DIRECT_CONNECT(
+			NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(20)) + NRF_GPIOTE_IRQ_GROUP,
+			IRQ_PRIO, gpiote_20_direct_isr, 0);
 	}
 
 	if (!nrfx_gpiote_init_check(&gpiote30_instance)) {
@@ -124,8 +145,9 @@ static int gpiote_init(void)
 			return -EIO;
 		}
 
-		IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(30)) + NRF_GPIOTE_IRQ_GROUP,
-			    IRQ_PRIO, NRFX_GPIOTE_INST_HANDLER_GET(30), 0, 0);
+		IRQ_DIRECT_CONNECT(
+			NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(30)) + NRF_GPIOTE_IRQ_GROUP,
+			IRQ_PRIO, gpiote_30_direct_isr, 0);
 	}
 #endif
 	return 0;
diff --git a/samples/Kconfig b/samples/Kconfig
@@ -10,6 +10,10 @@
 config MULTITHREADING
 	default n if !UNITY
 
+# Software ISR table is not needed if multithreading is not used
+config GEN_SW_ISR_TABLE
+	default n if !MULTITHREADING
+
 # Prevent moving SoftDevice RAM region
 # Need this when building without sysbuild
 config PARTITION_MANAGER_ENABLED
diff --git a/samples/bluetooth/ble_nus/src/main.c b/samples/bluetooth/ble_nus/src/main.c
@@ -348,6 +348,26 @@ static void ble_nus_evt_handler(const struct ble_nus_evt *evt)
 	}
 }
 
+ISR_DIRECT_DECLARE(uarte_direct_isr)
+{
+	NRFX_UARTE_INST_HANDLER_GET(NUS_UARTE_INST)();
+	return 0;
+}
+
+#if defined(CONFIG_NUS_LPUARTE)
+ISR_DIRECT_DECLARE(gpiote_20_direct_isr)
+{
+	NRFX_GPIOTE_INST_HANDLER_GET(20)();
+	return 0;
+}
+
+ISR_DIRECT_DECLARE(gpiote_30_direct_isr)
+{
+	NRFX_GPIOTE_INST_HANDLER_GET(30)();
+	return 0;
+}
+#endif
+
 /**
  * @brief Initalize UARTE driver.
  */
@@ -386,17 +406,17 @@ static int uarte_init(void)
 
 	/** We need to connect the IRQ ourselves. */
 
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(NUS_UARTE_INST)),
-		    CONFIG_NUS_UART_IRQ_PRIO, NRFX_UARTE_INST_HANDLER_GET(NUS_UARTE_INST), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(NUS_UARTE_INST)),
+			   CONFIG_NUS_UART_IRQ_PRIO, uarte_direct_isr, 0);
 
 	irq_enable(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(NUS_UARTE_INST)));
 
 #if defined(CONFIG_NUS_LPUARTE)
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(20)) + NRF_GPIOTE_IRQ_GROUP,
-		    CONFIG_GPIOTE_IRQ_PRIO, NRFX_GPIOTE_INST_HANDLER_GET(20), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(20)) + NRF_GPIOTE_IRQ_GROUP,
+			   CONFIG_GPIOTE_IRQ_PRIO, gpiote_20_direct_isr, 0);
 
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(30)) + NRF_GPIOTE_IRQ_GROUP,
-		    CONFIG_GPIOTE_IRQ_PRIO, NRFX_GPIOTE_INST_HANDLER_GET(30), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(30)) + NRF_GPIOTE_IRQ_GROUP,
+			   CONFIG_GPIOTE_IRQ_PRIO, gpiote_30_direct_isr, 0);
 
 	err = bm_lpuarte_init(&lpu, &lpu_cfg, uarte_evt_handler);
 	if (err != NRFX_SUCCESS) {
diff --git a/samples/peripherals/lpuarte/src/main.c b/samples/peripherals/lpuarte/src/main.c
@@ -52,6 +52,24 @@ static void lpuarte_event_handler(nrfx_uarte_event_t const *event, void *ctx)
 	}
 }
 
+ISR_DIRECT_DECLARE(gpiote_20_direct_isr)
+{
+	NRFX_GPIOTE_INST_HANDLER_GET(20)();
+	return 0;
+}
+
+ISR_DIRECT_DECLARE(gpiote_30_direct_isr)
+{
+	NRFX_GPIOTE_INST_HANDLER_GET(30)();
+	return 0;
+}
+
+ISR_DIRECT_DECLARE(lpuarte_direct_isr)
+{
+	NRFX_UARTE_INST_HANDLER_GET(BOARD_APP_LPUARTE_INST)();
+	return 0;
+}
+
 /* Initialize UARTE driver. */
 static uint32_t uarte_init(void)
 {
@@ -71,15 +89,14 @@ static uint32_t uarte_init(void)
 
 	lpu_cfg.uarte_cfg.interrupt_priority = CONFIG_LPUARTE_IRQ_PRIO;
 
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(20)) + NRF_GPIOTE_IRQ_GROUP,
-		    CONFIG_LPUARTE_GPIOTE_IRQ_PRIO, NRFX_GPIOTE_INST_HANDLER_GET(20), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(20)) + NRF_GPIOTE_IRQ_GROUP,
+			   CONFIG_LPUARTE_GPIOTE_IRQ_PRIO, gpiote_20_direct_isr, 0);
 
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(30)) + NRF_GPIOTE_IRQ_GROUP,
-		    CONFIG_LPUARTE_GPIOTE_IRQ_PRIO, NRFX_GPIOTE_INST_HANDLER_GET(30), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_GPIOTE_INST_GET(30)) + NRF_GPIOTE_IRQ_GROUP,
+			   CONFIG_LPUARTE_GPIOTE_IRQ_PRIO, gpiote_30_direct_isr, 0);
 
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_LPUARTE_INST)),
-		    CONFIG_LPUARTE_IRQ_PRIO,
-		    NRFX_UARTE_INST_HANDLER_GET(BOARD_APP_LPUARTE_INST), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_LPUARTE_INST)),
+			   CONFIG_LPUARTE_IRQ_PRIO, lpuarte_direct_isr, 0);
 
 	irq_enable(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_LPUARTE_INST)));
 
diff --git a/samples/peripherals/pwm/src/main.c b/samples/peripherals/pwm/src/main.c
@@ -27,6 +27,12 @@ static void pwm_handler(nrfx_pwm_evt_type_t event_type, void *ctx)
 	curr_loop++;
 }
 
+ISR_DIRECT_DECLARE(pwm_direct_isr)
+{
+	NRFX_PWM_INST_HANDLER_GET(20)();
+	return 0;
+}
+
 int main(void)
 {
 	nrfx_err_t err;
@@ -49,8 +55,9 @@ int main(void)
 
 	LOG_INF("PWM sample started");
 
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_PWM_INST_GET(PWM_INST_IDX)),
-		    CONFIG_PWM_IRQ_PRIO, NRFX_PWM_INST_HANDLER_GET(20), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_PWM_INST_GET(PWM_INST_IDX)),
+			   CONFIG_PWM_IRQ_PRIO,
+			   pwm_direct_isr, 0);
 
 	err = nrfx_pwm_init(&pwm_instance, &config, pwm_handler, &pwm_instance);
 	if (err != NRFX_SUCCESS) {
diff --git a/samples/peripherals/uarte/src/main.c b/samples/peripherals/uarte/src/main.c
@@ -85,6 +85,12 @@ static void uarte_event_handler(nrfx_uarte_event_t const *event, void *ctx)
 	}
 }
 
+ISR_DIRECT_DECLARE(uarte_direct_isr)
+{
+	NRFX_UARTE_INST_HANDLER_GET(BOARD_APP_UARTE_INST)();
+	return 0;
+}
+
 /* Initialize UARTE driver. */
 static int uarte_init(void)
 {
@@ -106,9 +112,9 @@ static int uarte_init(void)
 	uarte_config.interrupt_priority = CONFIG_UARTE_IRQ_PRIO;
 
 	/* We need to connect the IRQ ourselves. */
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_UARTE_INST)),
-		    CONFIG_UARTE_IRQ_PRIO,
-		    NRFX_UARTE_INST_HANDLER_GET(BOARD_APP_UARTE_INST), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_UARTE_INST)),
+			   CONFIG_UARTE_IRQ_PRIO,
+			   uarte_direct_isr, 0);
 
 	irq_enable(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_UARTE_INST)));
 
diff --git a/subsys/logging/backends/log_backend_bm_uarte.c b/subsys/logging/backends/log_backend_bm_uarte.c
@@ -20,6 +20,12 @@ static char uarte_tx_buf[CONFIG_LOG_BACKEND_BM_UARTE_BUFFER_SIZE];
 static int log_out(uint8_t *data, size_t length, void *ctx);
 LOG_OUTPUT_DEFINE(bm_lbu_output, log_out, lbu_buffer, CONFIG_LOG_BACKEND_BM_UARTE_BUFFER_SIZE);
 
+ISR_DIRECT_DECLARE(log_backend_bm_uarte_direct_isr)
+{
+	NRFX_UARTE_INST_HANDLER_GET(BOARD_CONSOLE_UARTE_INST)();
+	return 0;
+}
+
 static int uarte_init(void)
 {
 	int err;
@@ -42,10 +48,9 @@ static int uarte_init(void)
 	uarte_config.tx_cache.length = sizeof(uarte_tx_buf);
 
 	/** We need to connect the IRQ ourselves. */
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(
-		NRF_UARTE_INST_GET(BOARD_CONSOLE_UARTE_INST)),
-		CONFIG_LOG_BACKEND_BM_UARTE_IRQ_PRIO,
-		NRFX_UARTE_INST_HANDLER_GET(BOARD_CONSOLE_UARTE_INST), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_CONSOLE_UARTE_INST)),
+			   CONFIG_LOG_BACKEND_BM_UARTE_IRQ_PRIO,
+			   log_backend_bm_uarte_direct_isr, 0);
 
 	irq_enable(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_CONSOLE_UARTE_INST)));
 
diff --git a/subsys/mgmt/mcumgr/transport/src/bm_uart_mcumgr.c b/subsys/mgmt/mcumgr/transport/src/bm_uart_mcumgr.c
@@ -196,6 +196,12 @@ void uart_mcumgr_register(uart_mcumgr_recv_fn *cb)
 	uart_mcumgr_recv_cb = cb;
 }
 
+ISR_DIRECT_DECLARE(bm_uart_mcumgr_direct_isr)
+{
+	NRFX_UARTE_INST_HANDLER_GET(BOARD_APP_UARTE_INST)();
+	return 0;
+}
+
 /**
  * @brief Initialize UARTE driver.
  */
@@ -219,9 +225,9 @@ static int bm_uarte_init(void)
 	uarte_config.interrupt_priority = CONFIG_MCUMGR_TRANSPORT_BM_UART_UARTE_IRQ_PRIO;
 
 	/** We need to connect the IRQ ourselves. */
-	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_UARTE_INST)),
-		    CONFIG_MCUMGR_TRANSPORT_BM_UART_UARTE_IRQ_PRIO,
-		    NRFX_UARTE_INST_HANDLER_GET(BOARD_APP_UARTE_INST), 0, 0);
+	IRQ_DIRECT_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_UARTE_INST)),
+			   CONFIG_MCUMGR_TRANSPORT_BM_UART_UARTE_IRQ_PRIO,
+			   bm_uart_mcumgr_direct_isr, 0);
 
 	irq_enable(NRFX_IRQ_NUMBER_GET(NRF_UARTE_INST_GET(BOARD_APP_UARTE_INST)));
 
diff --git a/subsys/softdevice_handler/nrf_sdh.c b/subsys/softdevice_handler/nrf_sdh.c
@@ -280,15 +280,15 @@ void SD_EVT_IRQHandler(void)
 
 #endif /* NRF_SDH_DISPATCH_MODEL */
 
-static void isr_handler(const void *arg)
+ISR_DIRECT_DECLARE(sd_direct_isr)
 {
-	ARG_UNUSED(arg);
 	SD_EVT_IRQHandler();
+	return 0;
 }
 
 static int sd_irq_init(void)
 {
-	IRQ_CONNECT(SD_EVT_IRQn, 4, isr_handler, NULL, 0);
+	IRQ_DIRECT_CONNECT(SD_EVT_IRQn, 4, sd_direct_isr, 0);
 	irq_enable(SD_EVT_IRQn);
 
 	return 0;
