sw/tests: Add dma_2d test

sw/tests/dma_2d.c

@@ -0,0 +1,40 @@
+// Copyright 2024 ETH Zurich and University of Bologna.
+// Licensed under the Apache License, Version 2.0, see LICENSE for details.
+// SPDX-License-Identifier: Apache-2.0
+//
+// Paul Scheffler <[email protected]>
+//
+// Simple test for iDMA. This is intended *only for execution from SPM*.
+
+#include "util.h"
+#include "dif/clint.h"
+#include "dif/dma.h"
+
+int main(void) {
+    volatile char src_cached[] = "This is a DMA test";
+    volatile char gold[] = "This ishis is is is as is a DMA test!";
+
+    // Allocate destination memory in SPM
+    volatile char dst_cached[sizeof(gold)];
+
+    // Get pointer to uncached SPM source and destination
+    volatile char *src = src_cached + 0x04000000;
+    volatile char *dst = dst_cached + 0x04000000;
+
+    // Copy from cached to uncached source to ensure it is DMA-accessible
+    for (unsigned i = 0; i < sizeof(src_cached); ++i) src[i] = src_cached[i];
+
+    // Pre-write finishing "!\0" to guard against overlength transfers
+    dst[sizeof(gold) - 2] = '!';
+    dst[sizeof(gold) - 1] = '\0';
+
+    // Issue blocking 2D memcpy (exclude null terminator from source)
+    sys_dma_2d_blk_memcpy((uintptr_t)(void *)dst, (uintptr_t)(void *)src, sizeof(src_cached) - 4, 7,
+                          1, 4);
+
+    // Check destination string
+    int errors = sizeof(gold);
+    for (unsigned i = 0; i < sizeof(gold); ++i) errors -= (dst[i] == gold[i]);
+
+    return errors;
+}