create wdt device discovery

discuss: per wrv32em status, consider moving custom wdt format to dtb or
pci device discovery (potentially both: we have the framework for pci.ko
extension after using dtb to discover memory and pci devices)

7 files changed, 108 insertions, 6 deletions

diff --git a/.gitignore b/.gitignore
index e2e7327..22e0bda 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,3 @@
 /out
+/.cache
+compile_commands.json
diff --git a/Makefile b/Makefile
index 9465dd1..2de743c 100644
--- a/Makefile
+++ b/Makefile
@@ -109,7 +109,7 @@ $(KERNEL_ELF): $(KERNEL_OBJS) linker.ld | $(BIN_DIR)
 
 $(KERNEL_BIN): $(KERNEL_ELF) | $(BIN_DIR)
 	@echo " OBJCOPY $@"
-	$(OBJCOPY) $(OBJCOPY_FLAG) $(KERNEL_ELF) $(KERNEL_BIN)
+	$(OBJCOPY) $(KERNEL_OBJCOPY_FLAG) $(KERNEL_ELF) $(KERNEL_BIN)
 
 $(OBJ_DIR)/%.o: %.c# | $(OBJ_DIR)/%
 	@mkdir -p $(dir $@)
diff --git a/include/mem.h b/include/mem.h
new file mode 100644
index 0000000..12976df
--- /dev/null
+++ b/include/mem.h
@@ -0,0 +1,22 @@
+#pragma once
+#include <types.h>
+
+#define EHEAP_SIZE (512 * 1024)
+
+typedef enum {
+    PAGE_FREE,
+    PAGE_ALLOCATED
+} MemoryPageAvailability;
+
+struct page {
+    void* locator;
+    MemoryPageAvailability availability;
+    struct page* next;
+};
+
+void* kmalloc(size_t size);
+void* memcpy(void* to, const void* from,size_t size);
+
+void* kemalloc(size_t size);
+
+extern struct page root;
diff --git a/include/types.h b/include/types.h
new file mode 100644
index 0000000..4c7965c
--- /dev/null
+++ b/include/types.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#define NULL (void*)0
+
+#define size_t __wk_size_t
+#define uint8_t __wk_uint8_t
+#define uint16_t __wk_uint16_t
+#define uint32_t __wk_uint32_t
+#define uint64_t __wk_uint64_t
+#define be32_to_cpu(x) __builtin_bswap32(x)
+
+typedef __UINTPTR_TYPE__ __wk_size_t;
+typedef __UINT8_TYPE__ __wk_uint8_t;
+typedef __UINT16_TYPE__ __wk_uint16_t;
+typedef __UINT32_TYPE__ __wk_uint32_t;
+typedef __UINT64_TYPE__ __wk_uint64_t;
+
diff --git a/include/wdt.h b/include/wdt.h
new file mode 100644
index 0000000..31739ab
--- /dev/null
+++ b/include/wdt.h
@@ -0,0 +1,18 @@
+#pragma once
+#include <types.h>
+
+#define WDT_MAGIC 0x67674141
+
+struct wdt_device {
+    uint32_t type;
+    uint32_t driver_id;
+    uint32_t start;
+    uint32_t size;
+};
+
+struct wdt_root {
+    uint32_t magic;
+    uint32_t count;
+    struct wdt_device devices[];
+};
+
diff --git a/kernel/kernel.c b/kernel/kernel.c
index 753f4a5..3dbf0d1 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -1,3 +1,5 @@
+#include <types.h>
+#include <wdt.h>
 #define UART_BASE 0x10000000  // Example UART address
 
 static inline void putchar(char c) {
@@ -11,10 +13,19 @@ static void print_string(const char *str) {
     }
 }
 
-void kernel_main(void) {
-    print_string("Hello from RISC-V kernel!\n");
-    
-    while (1) {
-        // Wait
+void kernel_main(void *wdt) {
+    struct wdt_root *root = wdt;
+    print_string("deserialized all!\n");
+    uint32_t count = root->count;
+    for (uint32_t i = 0; i < count; i++) {
+        print_string("deserializing wdt node!\n");
+        print_string("device type: ");
+        if (root->devices[i].type == 0) {
+            print_string("mem");
+        } else {
+            print_string("unknown");
+        }
+        print_string("\n");
     }
+    while(1);
 }
diff --git a/kernel/mem.c b/kernel/mem.c
new file mode 100644
index 0000000..531dd81
--- /dev/null
+++ b/kernel/mem.c
@@ -0,0 +1,32 @@
+#include <types.h>
+#include <mem.h>
+
+static char eheap[EHEAP_SIZE] = {0};
+static size_t eheap_off = 0;
+
+void* kmalloc(size_t size) {
+    return (void*)size;
+}
+
+void* kemalloc(size_t size) {
+    size = (size + 7) & ~7;
+
+    if (eheap_off + size > EHEAP_SIZE) {
+        return NULL;
+    }
+
+    void *ptr = &eheap[eheap_off];
+    eheap_off += size;
+    return ptr;
+}
+
+void* memcpy(void *to, const void *from, size_t size) {
+    char *dest = (char *)to;
+    const char *src = (const char *)from;
+
+    while (size--) {
+        *dest++ = *src++;
+    }
+
+    return dest;
+}