Added SDRAM + Lib + llext_export changes

Author: mjs513

Diff for: libraries/Zephyr_SDRAM/examples/SDRAM_operations/SDRAM_operations.ino

@@ -0,0 +1,68 @@
+/*
+    How to interact with external SDRAM on Portenta H7
+
+    The board comes with an hefty 8MB of external fast RAM, which can be used:
+    - as a framebuffer (raw mode)
+    - as an expansion of on-chip RAM to store "standard" data
+
+    This example shows both the usages
+*/
+
+#include "SDRAM.h"
+
+void nonFrameBuffer() {
+    // Initilize SDRAM for non-framebuffer operations
+    SDRAM.begin(); // is the same as SDRAM.begin(SDRAM_START_ADDRESS);
+
+    // Now we can malloc() and free() in the whole RAM space
+    // For example, let's create a 7MB array
+    uint8_t* myVeryBigArray = (uint8_t*)SDRAM.malloc(7 * 1024 * 1024);
+
+    // and a small one
+    uint8_t* mySmallArray = (uint8_t*)SDRAM.malloc(128);
+
+    // and use then as usual
+    for (int i = 0; i<128; i++) {
+        myVeryBigArray[i] = i;
+        mySmallArray[i] = i*2;
+    }
+
+    // free the memory when you don't need them anymore
+    SDRAM.free(myVeryBigArray);
+}
+
+void frameBuffer() {
+    // In case we want a framebuffer-like area at the beginning of the flash,
+    // simply initialize the memory as
+
+    SDRAM.begin(SDRAM_START_ADDRESS + 2 * 1024 * 1024);
+    // 2MB of contiguous memory available at the beginning
+
+    uint32_t* framebuffer = (uint32_t*)SDRAM_START_ADDRESS;
+
+    // We can't allocate anymore the huge 7MB array
+
+    uint8_t* myVeryBigArray = (uint8_t*)SDRAM.malloc(7 * 1024 * 1024);
+    if (myVeryBigArray == NULL) {
+        Serial.println("Oops, too big :)");
+    }
+
+}
+
+void setup() {
+    Serial.begin(115200);
+    while (!Serial);
+
+    frameBuffer();
+    // Uncomment to test the other functionality 
+    // nonFrameBuffer();
+
+    // Sort of memtest for stability, useful for testing when overclocking
+    if (SDRAM.test()) {
+        Serial.println("SDRAM completely functional");
+    }
+}
+
+void loop() {
+    
+}

Diff for: libraries/Zephyr_SDRAM/library.properties

@@ -0,0 +1,9 @@
+name=Portenta_SDRAM
+version=1.0
+author=Arduino
+maintainer=Arduino <[email protected]>
+sentence=Interact with external SDRAM chip on Portenta H7
+paragraph=
+category=Other
+url=https://github.com/arduino/ArduinoCore-mbed/tree/master/libraries/Portenta_SDRAM
+architectures=*

Diff for: libraries/Zephyr_SDRAM/src/SDRAM.cpp

@@ -0,0 +1,69 @@
+#include "SDRAM.h"
+#include "Arduino.h"
+
+int SDRAMClass::begin(uint32_t start_address) {
+	if (start_address) {
+		malloc_addblock((void*)start_address, SDRAM_END_ADDRESS - start_address);
+	}
+
+	return 1;
+}
+
+void* SDRAMClass::malloc(size_t size) {
+	return ea_malloc(size);
+}
+
+void SDRAMClass::free(void* ptr) {
+	ea_free(ptr);
+}
+
+bool SDRAMClass::test(bool fast, Stream& _serial) {
+    uint8_t const pattern = 0xaa;
+    uint8_t const antipattern = 0x55;
+    uint8_t *const mem_base = (uint8_t*)SDRAM_START_ADDRESS;
+
+    /* test data bus */
+    for (uint8_t i = 1; i; i <<= 1) {
+        *mem_base = i;
+        if (*mem_base != i) {
+            _serial.println("data bus lines test failed! data (" + String(i) + ")");
+            __asm__ volatile ("BKPT");
+        }
+    }
+
+    /* test address bus */
+    /* Check individual address lines */
+    for (uint32_t i = 1; i < HW_SDRAM_SIZE; i <<= 1) {
+        mem_base[i] = pattern;
+        if (mem_base[i] != pattern) {
+            _serial.println("address bus lines test failed! address ("+ String((uint32_t)&mem_base[i], HEX) + ")");
+            __asm__ volatile ("BKPT");
+        }
+    }
+
+    /* Check for aliasing (overlaping addresses) */
+    mem_base[0] = antipattern;
+    for (uint32_t i = 1; i < HW_SDRAM_SIZE; i <<= 1) {
+        if (mem_base[i] != pattern) {
+            _serial.println("address bus overlap! address ("+ String((uint32_t)&mem_base[i], HEX) + ")");
+            __asm__ volatile ("BKPT");
+        }
+    }
+
+    /* test all ram cells */
+    if (!fast) {
+        for (uint32_t i = 0; i < HW_SDRAM_SIZE; ++i) {
+            mem_base[i] = pattern;
+            if (mem_base[i] != pattern) {
+                _serial.println("address bus test failed! address ("+ String((uint32_t)&mem_base[i], HEX) + ")");
+                __asm__ volatile ("BKPT");
+            }
+        }
+    } else {
+        memset(mem_base, pattern, HW_SDRAM_SIZE);
+    }
+
+    return true;
+}
+
+SDRAMClass SDRAM;

Diff for: libraries/Zephyr_SDRAM/src/SDRAM.h

@@ -0,0 +1,27 @@
+#ifndef __SDRAM_H
+#define __SDRAM_H
+
+#include "ea_malloc.h"
+
+#ifdef __cplusplus
+
+#include "Arduino.h"
+
+#define SDRAM_END_ADDRESS			(0xc0800000)
+#define SDRAM_START_ADDRESS			(0xc0000000)
+#define HW_SDRAM_SIZE						(8 * 1024 * 1024)
+
+class SDRAMClass {
+public:
+	SDRAMClass() {}
+	int begin(uint32_t start_address = SDRAM_START_ADDRESS);
+	void* malloc(size_t size);
+	void free(void* ptr);
+	bool test(bool fast = false, Stream& _serial = Serial);
+private:
+
+};
+extern SDRAMClass SDRAM;
+
+#endif
+#endif // __SDRAM_H

Diff for: libraries/ea_malloc/ea_malloc.h

@@ -0,0 +1,46 @@
+/*
+* Copyright © 2017 Embedded Artistry LLC.
+* License: MIT. See LICENSE file for details.
+*/
+
+#ifndef MALLOC_H_
+#define MALLOC_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif //__cplusplus
+
+#include <stdlib.h>
+
+/**
+* @brief Assign blocks of memory for use by malloc().
+*
+* Initializes the malloc() backend with a memory address and memory pool size.
+* This memory is assumed to be owned by malloc() and is vended out when memory is requested.
+*   Multiple blocks can be added.
+*
+* NOTE: This API must be called before malloc() can be used. If you call malloc() before
+*   allocating memory, malloc() will return NULL because there is no available memory
+* to provide to the user.
+*
+* @param addr Pointer to the memory block address that you are providing to malloc()
+* @param size Size of the memory block that you are providing to malloc()
+*/
+void malloc_addblock(void* addr, size_t size);
+
+/**
+* @brief Initialize Malloc
+*
+* Weakly linked, can be overridden based on your needs.
+* Each malloc implementation contains a different set of initialization requirements
+*/
+void malloc_init(void);
+
+void* ea_malloc(size_t size);
+void ea_free(void* ptr);
+
+#ifdef __cplusplus
+}
+#endif //__cplusplus
+
+#endif //MALLOC_H_