move to monorepo

+ Will probably have to make some changes to dir layout to make things
  make more sense

1 files changed, 79 insertions, 0 deletions

diff --git a/triscv/src/mem.c b/triscv/src/mem.c
new file mode 100644
index 0000000..5d70896
--- /dev/null
+++ b/triscv/src/mem.c
@@ -0,0 +1,79 @@
+#include <triscv/mem.h>
+#include <string.h>
+
+struct mem {
+	size_t size;
+	uint32_t buf[];
+};
+
+struct mem *mem_create(size_t size)
+{
+	struct mem *mem = calloc(1, sizeof(struct mem) + size * sizeof(mem->buf[0]));
+	mem->size = size;
+	return mem;
+}
+
+void mem_destroy(struct mem *mem)
+{
+	free(mem);
+}
+
+void mem_init(struct mem *mem, const void *buf, size_t len)
+{
+	assert((len * 3) < mem->size);
+	for (size_t i = 0; i < len * 3; i += 3) {
+		tri_t t = ((tri_t *)buf)[i / 3];
+		mem->buf[i + 0] = tri_mask(t, 9);
+		t = tri_sr(t, 9);
+
+		mem->buf[i + 1] = tri_mask(t, 9);
+		t = tri_sr(t, 9);
+
+		mem->buf[i + 2] = tri_mask(t, 9);
+	}
+}
+
+static void mem_write1(struct cpu *cpu, struct mem *mem, pm_t addr, tri_t t)
+{
+	(void)cpu;
+	(void)mem;
+	(void)addr;
+	(void)t;
+}
+
+static void mem_write3(struct cpu *cpu, struct mem *mem, pm_t addr, tri_t t)
+{
+	(void)cpu;
+	(void)mem;
+	(void)addr;
+	(void)t;
+}
+
+static tri_t mem_read1(struct cpu *cpu, struct mem *mem, pm_t addr)
+{
+	(void)cpu;
+	tri_t t = (tri_t)mem->buf[addr];
+	return tri_mask(t, 9);
+}
+
+static tri_t mem_read3(struct cpu *cpu, struct mem *mem, pm_t addr)
+{
+	(void)cpu;
+	/* not necessarily ideal, but I guess it works for now */
+	tri_t t0 = mem_read1(cpu, mem, addr + 0);
+	tri_t t1 = mem_read1(cpu, mem, addr + 1);
+	tri_t t2 = mem_read1(cpu, mem, addr + 2);
+	return t0 | tri_sl(t1, 9) | tri_sl(t2, 18);
+}
+
+struct dev mem_dev(struct mem *mem)
+{
+	return (struct dev){
+		.dev = mem,
+		.size = mem->size,
+		.write1 = (dev_write1_t)mem_write1,
+		.write3 = (dev_write3_t)mem_write3,
+		.read1 = (dev_read1_t)mem_read1,
+		.read3 = (dev_read3_t)mem_read3
+	};
+}