Added MMU

src/cpu/exception.c

@@ -0,0 +1,25 @@
+#include "exception.h"
+
+#include <stdio.h>
+
+void exception_trigger(rv32_cpu_t* cpu, uint32_t scause)
+{
+    // An exception can only be triggered by the CPU itself,
+    // so we know we already own the mutex
+    // We are in the CPU thread itself, but we need
+    // the return of this function to be the beginning of
+    // the cpu loop
+    // To achieve that, we can just call cpu_loop (noreturn)
+    // at the end of this function
+
+    // Save execution context, so that 'mret/sret/..' can restore it
+    // TODO
+
+    // Set PC to STVEC, and set SCAUSE
+    // TODO: If PC cannot be mmu_resolved, throw a 'double fault' ?
+    cpu->pc = cpu->csr[CSR_STVEC];
+    cpu->csr[CSR_SCAUSE] = scause;
+
+    pthread_mutex_unlock(&cpu0_mutex);
+    cpu_loop(cpu);
+}