stm32: Implement port backend for libmetal.

Signed-off-by: iabdalkader <i.abdalkader@gmail.com>

ports/stm32/Makefile

@@ -422,6 +422,13 @@ endif
 
 endif # MICROPY_PY_BLUETOOTH
 
+# Add stm32-specific implementation of libmetal (and optionally OpenAMP's rproc).
+# Note: libmetal code is generated via a pre-processor so ensure that runs first.
+ifeq ($(MICROPY_PY_OPENAMP),1)
+SRC_C += mpmetalport.c
+$(BUILD)/mpmetalport.o: $(BUILD)/openamp/metal/config.h
+endif
+
 # SRC_O should be placed first to work around this LTO bug with binutils <2.35:
 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83967
 OBJ += $(addprefix $(BUILD)/, $(SRC_O))

ports/stm32/irq.h

@@ -174,6 +174,8 @@ static inline void restore_irq_pri(uint32_t state) {
 
 #define IRQ_PRI_SPI             NVIC_EncodePriority(NVIC_PRIORITYGROUP_4, 8, 0)
 
+#define IRQ_PRI_HSEM            NVIC_EncodePriority(NVIC_PRIORITYGROUP_4, 10, 0)
+
 // Interrupt priority for non-special timers.
 #define IRQ_PRI_TIMX            NVIC_EncodePriority(NVIC_PRIORITYGROUP_4, 13, 0)
 

ports/stm32/mpmetalport.c

@@ -0,0 +1,107 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2023 Arduino SA
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * libmetal stm32 port.
+ */
+
+#include "py/mperrno.h"
+#include "py/mphal.h"
+
+#include "mpu.h"
+
+#include "metal/sys.h"
+#include "metal/utilities.h"
+#include "metal/device.h"
+
+struct metal_state _metal;
+static mp_sched_node_t rproc_notify_node;
+
+int metal_sys_init(const struct metal_init_params *params) {
+    metal_unused(params);
+
+    // Clear HSEM pending IRQ.
+    HSEM_COMMON->ICR |= (uint32_t)__HAL_HSEM_SEMID_TO_MASK(METAL_HSEM_MASTER_ID);
+    HAL_NVIC_ClearPendingIRQ(HSEM1_IRQn);
+
+    // Enable and configure HSEM.
+    __HAL_RCC_HSEM_CLK_ENABLE();
+    NVIC_SetPriority(HSEM1_IRQn, IRQ_PRI_HSEM);
+    HAL_NVIC_EnableIRQ(HSEM1_IRQn);
+    HAL_HSEM_ActivateNotification(__HAL_HSEM_SEMID_TO_MASK(METAL_HSEM_MASTER_ID));
+
+    #ifndef VIRTIO_USE_DCACHE
+    // If cache management is not enabled, configure the MPU to disable caching
+    // for the entire shared memory region.
+    uint32_t irq_state = mpu_config_start();
+    mpu_config_region(MPU_REGION_OPENAMP, METAL_MPU_REGION_BASE, MPU_CONFIG_SHARED_UNCACHED(METAL_MPU_REGION_SIZE));
+    mpu_config_end(irq_state);
+    #endif
+
+    metal_bus_register(&metal_generic_bus);
+    return 0;
+}
+
+void metal_sys_finish(void) {
+    HAL_NVIC_DisableIRQ(HSEM1_IRQn);
+    HAL_HSEM_DeactivateNotification(__HAL_HSEM_SEMID_TO_MASK(METAL_HSEM_MASTER_ID));
+    __HAL_RCC_HSEM_CLK_DISABLE();
+    metal_bus_unregister(&metal_generic_bus);
+}
+
+unsigned int sys_irq_save_disable(void) {
+    return disable_irq();
+}
+
+void sys_irq_restore_enable(unsigned int state) {
+    enable_irq(state);
+}
+
+void *metal_machine_io_mem_map(void *va, metal_phys_addr_t pa,
+    size_t size, unsigned int flags) {
+    metal_unused(pa);
+    metal_unused(size);
+    metal_unused(flags);
+    return va;
+}
+
+void metal_machine_cache_flush(void *addr, unsigned int len) {
+    SCB_CleanDCache_by_Addr(addr, len);
+}
+
+void metal_machine_cache_invalidate(void *addr, unsigned int len) {
+    SCB_InvalidateDCache_by_Addr(addr, len);
+}
+
+int metal_rproc_notify(void *priv, uint32_t id) {
+    HAL_HSEM_FastTake(METAL_HSEM_REMOTE_ID);
+    HAL_HSEM_Release(METAL_HSEM_REMOTE_ID, 0);
+    return 0;
+}
+
+void HSEM1_IRQHandler(void) {
+    HAL_HSEM_IRQHandler();
+    mp_sched_schedule_node(&rproc_notify_node, openamp_remoteproc_notified);
+    HAL_HSEM_ActivateNotification(__HAL_HSEM_SEMID_TO_MASK(METAL_HSEM_MASTER_ID));
+}

ports/stm32/mpmetalport.h

@@ -0,0 +1,76 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2023 Arduino SA
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * libmetal stm32 port.
+ */
+#ifndef MICROPY_INCLUDED_STM32_MPMETALPORT_H
+#define MICROPY_INCLUDED_STM32_MPMETALPORT_H
+
+#include <stdlib.h>
+#include "py/mphal.h"
+#include "py/runtime.h"
+
+#define METAL_HAVE_STDATOMIC_H      0
+#define METAL_HAVE_FUTEX_H          0
+
+#define METAL_MAX_DEVICE_REGIONS    2
+
+#define METAL_HSEM_REMOTE_ID        0
+#define METAL_HSEM_MASTER_ID        1
+
+// Set to 1 to enable log output.
+#define METAL_LOG_HANDLER_ENABLE    0
+
+#define metal_cpu_yield()
+
+// Shared memory config
+#define METAL_SHM_NAME              "OPENAMP_SHM"
+// Note 1K must be reserved at the start of the openamp
+// shared memory region, for the shared resource table.
+#define METAL_RSC_ADDR              ((void *)_openamp_shm_region_start)
+#define METAL_RSC_SIZE              (1024)
+
+#define METAL_SHM_ADDR              ((metal_phys_addr_t)(_openamp_shm_region_start + METAL_RSC_SIZE))
+#define METAL_SHM_SIZE              ((size_t)(_openamp_shm_region_end - _openamp_shm_region_start - METAL_RSC_SIZE))
+
+#define METAL_MPU_REGION_BASE       ((uint32_t)_openamp_shm_region_start)
+#define METAL_MPU_REGION_SIZE       (MPU_REGION_SIZE_64KB)
+
+extern const char _openamp_shm_region_start[];
+extern const char _openamp_shm_region_end[];
+
+int metal_rproc_notify(void *priv, uint32_t id);
+extern void openamp_remoteproc_notified(mp_sched_node_t *node);
+
+static inline int __metal_sleep_usec(unsigned int usec) {
+    mp_hal_delay_us(usec);
+    return 0;
+}
+
+static inline void metal_generic_default_poll(void) {
+    MICROPY_EVENT_POLL_HOOK
+}
+
+#endif // MICROPY_INCLUDED_STM32_METAL_PORT_H