mbv: use new ninja-based build

mbv/apps/app.ld

@@ -0,0 +1,42 @@
+MEMORY
+{
+    RAM (rwx) : ORIGIN = 0x00000800, LENGTH = 14336
+}
+
+_vector_table = 0x0;
+
+SECTIONS
+{
+    .text :
+    {
+        _text_begin = .;
+        KEEP(*(.start))
+
+        *(.text*)
+        _text_end = .;
+
+        *(.rodata*)
+    } > RAM
+
+    .bss (NOLOAD) :
+    {
+        _bss_begin = .;
+        *(.bss*)
+        *(COMMON)
+        _bss_end = .;
+    } > RAM
+
+    .data :
+    {
+        *(.data*)
+
+        __exidx_start = .;
+        *(.exidx*)
+        __exidx_end = .;
+    } > RAM
+
+    _heap_begin = .;
+
+    _initial_stack_pointer = 16384;
+    _heap_end = _initial_stack_pointer - 1024;
+}

mbv/apps/helloworld/helloworld.cc

@@ -0,0 +1,26 @@
+#include <cstdint>
+
+struct Gpio {
+    volatile uint32_t data;
+};
+
+#define gpio0 ((Gpio*)0x40000000)
+
+void sleep(int ms) {
+    for (int m = 0; m < ms; m++) {
+        for (int i = 0; i < 10000; i++) {
+            asm volatile ( "" );
+        }
+    }
+}
+
+int main() {
+    int out = 0;
+
+    while (1) {
+        gpio0->data = out;
+        out = (out + 1) % 256;
+
+        sleep(10);
+    }
+}