feat: init

kernel/src/emk.c

@@ -0,0 +1,107 @@
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include <boot/limine.h>
+
+__attribute__((used, section(".limine_requests"))) static volatile LIMINE_BASE_REVISION(3);
+__attribute__((used, section(".limine_requests"))) static volatile struct limine_framebuffer_request framebuffer_request = {
+    .id = LIMINE_FRAMEBUFFER_REQUEST,
+    .revision = 0};
+
+__attribute__((used, section(".limine_requests_start"))) static volatile LIMINE_REQUESTS_START_MARKER;
+__attribute__((used, section(".limine_requests_end"))) static volatile LIMINE_REQUESTS_END_MARKER;
+
+void *memcpy(void *restrict dest, const void *restrict src, size_t n)
+{
+    uint8_t *restrict pdest = (uint8_t *restrict)dest;
+    const uint8_t *restrict psrc = (const uint8_t *restrict)src;
+
+    for (size_t i = 0; i < n; i++)
+    {
+        pdest[i] = psrc[i];
+    }
+
+    return dest;
+}
+
+void *memset(void *s, int c, size_t n)
+{
+    uint8_t *p = (uint8_t *)s;
+
+    for (size_t i = 0; i < n; i++)
+    {
+        p[i] = (uint8_t)c;
+    }
+
+    return s;
+}
+
+void *memmove(void *dest, const void *src, size_t n)
+{
+    uint8_t *pdest = (uint8_t *)dest;
+    const uint8_t *psrc = (const uint8_t *)src;
+
+    if (src > dest)
+    {
+        for (size_t i = 0; i < n; i++)
+        {
+            pdest[i] = psrc[i];
+        }
+    }
+    else if (src < dest)
+    {
+        for (size_t i = n; i > 0; i--)
+        {
+            pdest[i - 1] = psrc[i - 1];
+        }
+    }
+
+    return dest;
+}
+
+int memcmp(const void *s1, const void *s2, size_t n)
+{
+    const uint8_t *p1 = (const uint8_t *)s1;
+    const uint8_t *p2 = (const uint8_t *)s2;
+
+    for (size_t i = 0; i < n; i++)
+    {
+        if (p1[i] != p2[i])
+        {
+            return p1[i] < p2[i] ? -1 : 1;
+        }
+    }
+
+    return 0;
+}
+
+static void hcf(void)
+{
+    asm("cli");
+    for (;;)
+    {
+        asm("hlt");
+    }
+}
+
+void emk_entry(void)
+{
+    if (LIMINE_BASE_REVISION_SUPPORTED == false)
+    {
+        hcf();
+    }
+
+    if (framebuffer_request.response == NULL || framebuffer_request.response->framebuffer_count < 1)
+    {
+        hcf();
+    }
+
+    struct limine_framebuffer *framebuffer = framebuffer_request.response->framebuffers[0];
+    for (size_t i = 0; i < 100; i++)
+    {
+        volatile uint32_t *fb_ptr = framebuffer->address;
+        fb_ptr[i * (framebuffer->pitch / 4) + i] = 0xffffff;
+    }
+
+    hcf();
+}