Release: v4.0

Highlights:
- UART interrupt support
- Program memory optimisation
- Support for ztest and twister
- Context switch refignment
- Kernel and thread test cases
- Samples support
   - UART: Echo bot, native tty, passthrough
   - Blinky
   - Philosophers
   - Hello world
- Pin control driver
- New board support (sdPIC33AK512MPS512)
Fixes:
- Context switch fixes
- System timer fixes
- Build fixes

Signed-off-by: Muhammed Zamroodh <[email protected]>

Author: Lakshminarasimhan1998

arch/Kconfig

@@ -183,8 +183,6 @@ config DSPIC
 	select STACK_SENTINAL
 	select ATOMIC_OPERATIONS_C
 	select ARCH_HAS_VECTOR_TABLE_RELOCATION
-	select CPU_HAS_ICACHE
-	select CACHE_MANAGEMENT
 	select TICKLESS_CAPABLE
 	help
 	  dspic architecture

arch/dspic/CMakeLists.txt

@@ -3,6 +3,6 @@ if(CONFIG_BIG_ENDIAN)
 else()
     set_property(GLOBAL PROPERTY PROPERTY_OUTPUT_FORMAT elf32-little)
 endif()
-zephyr_include_directories(${XCDSC_TOOLCHAIN_PATH}/support/generic/h/)
+zephyr_include_directories(${DFP_ROOT}/support/generic/h/)
 zephyr_include_directories(include)
 add_subdirectory(core)

arch/dspic/Kconfig

@@ -20,4 +20,11 @@ config NUM_IRQS
 config GEN_IRQ_START_VECTOR
 	default 0
 
+config DSPIC33_IRQ_OFFLOAD_IRQ
+	int "IRQ number for irq_offload()"
+	default 34
+	help
+	  Select the interrupt number used by irq_offload().
+	  This must be a valid, software-triggerable interrupt on the dsPIC33.
+
 endmenu

arch/dspic/core/CMakeLists.txt

@@ -4,7 +4,7 @@ zephyr_library_sources(
     cpu_idle.c
     fatal.c
     irq_manage.c
-    isr_wrapper.c
+    isr_wrapper.S
     prep_c.c
     thread.c
     swap.c
@@ -13,6 +13,7 @@ zephyr_library_sources(
     init.S
     vector_table.S
     reset1.S
+    irq_offload.c
 )
 
 zephyr_linker_sources(ROM_START SORT_KEY 0x00 vector_table.ld)

arch/dspic/core/fatal.c

@@ -16,7 +16,7 @@ LOG_MODULE_REGISTER(dspic, 4);
 
 volatile uint32_t reason, address;
 
-#define EXCEPTION_HANDLER __attribute__((interrupt, no_auto_psv, weak))
+#define EXCEPTION_HANDLER __attribute__((interrupt, no_auto_psv, weak, naked))
 #define BUS_ERROR_MASK    0xF
 #define MATH_ERROR_MASK   0x1F
 #define GENERAL_TRAP_MASK 0x8000000Fu

arch/dspic/core/irq_manage.c

@@ -18,7 +18,6 @@ void z_irq_spurious(const void *unused)
 	ARG_UNUSED(unused);
 	while (1) {
 	}
-	return;
 }
 
 void arch_irq_enable(unsigned int irq)
@@ -31,8 +30,6 @@ void arch_irq_enable(unsigned int irq)
 
 	/* Enable the interrupt by setting it's bit in interrupt enable register*/
 	*int_enable_reg[reg_index] |= (uint32_t)(1u << bit_pos);
-
-	return;
 }
 
 int arch_irq_is_enabled(unsigned int irq)
@@ -56,8 +53,34 @@ void arch_irq_disable(unsigned int irq)
 
 	/* Disable the interrupt by clearing it's bit in interrupt enable register*/
 	*int_enable_reg[reg_index] &= (uint32_t)(~(1u << bit_pos));
+}
+
+bool arch_dspic_irq_isset(unsigned int irq)
+{
+	volatile uint32_t *int_ifs_reg[] = {&IFS0, &IFS1, &IFS2, &IFS3, &IFS4,
+					    &IFS5, &IFS6, &IFS7, &IFS8};
+	volatile int ret_ifs = false;
+	unsigned int reg_index = irq / (sizeof(uint32_t) << 3);
+	unsigned int bit_pos = irq % (sizeof(uint32_t) << 3);
 
-	return;
+	if ((bool)(void *)(*int_ifs_reg[reg_index] & (uint32_t)(1U << bit_pos))) {
+		ret_ifs = true;
+	}
+	return ret_ifs;
+}
+
+
+
+void z_dspic_enter_irq(int irq)
+{
+	volatile uint32_t *int_ifs_reg[] = {&IFS0, &IFS1, &IFS2, &IFS3, &IFS4,
+					    &IFS5, &IFS6, &IFS7, &IFS8};
+
+	unsigned int reg_index = (unsigned int)irq / (sizeof(uint32_t) << 3);
+	unsigned int bit_pos = (unsigned int)irq % (sizeof(uint32_t) << 3);
+
+	/* Enable the interrupt by setting it's bit in interrupt enable register*/
+	*int_ifs_reg[reg_index] |= (uint32_t)(1u << bit_pos);
 }
 
 #ifdef __cplusplus

arch/dspic/core/irq_offload.c

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2025, Microchip Technology Inc.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/kernel.h>
+#include <zephyr/kernel_structs.h>
+#include <kernel_internal.h>
+#include <zephyr/irq.h>
+#include <zephyr/irq_offload.h>
+#include <xc.h>
+
+static irq_offload_routine_t _offload_routine;
+static const void *offload_param;
+
+void z_irq_do_offload(void)
+{
+	irq_offload_routine_t tmp;
+
+	if (_offload_routine != NULL) {
+
+		tmp = _offload_routine;
+		_offload_routine = NULL;
+
+		tmp((const void *)offload_param);
+	}
+}
+
+void handler(void)
+{
+	z_irq_do_offload();
+}
+
+void arch_irq_offload_init(void)
+{
+	IRQ_CONNECT(CONFIG_DSPIC33_IRQ_OFFLOAD_IRQ, 1, handler, NULL, 0);
+}
+
+void arch_irq_offload(irq_offload_routine_t routine, const void *parameter)
+{
+	uint32_t key = irq_lock();
+
+	_offload_routine = routine;
+	offload_param = parameter;
+	irq_enable(CONFIG_DSPIC33_IRQ_OFFLOAD_IRQ);
+	z_dspic_enter_irq(CONFIG_DSPIC33_IRQ_OFFLOAD_IRQ);
+	irq_unlock(key);
+}