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-rw-r--r--loader_stage1.c25
1 files changed, 25 insertions, 0 deletions
diff --git a/loader_stage1.c b/loader_stage1.c
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index 0000000..d209c15
--- /dev/null
+++ b/loader_stage1.c
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+#include <stddef.h>
+#include <stdint.h>
+#include <global.h>
+
+char *const stage2_addr = ((void*) 0x4000);
+
+// there's one tricky thing about embedding file in executable;
+// mainly, symbols are visible to c code as extern chars, but the actual
+// values are their adresses... see the code below
+extern char
+ _binary_loader_stage2_img_start,
+ _binary_loader_stage2_img_end,
+ _binary_loader_stage2_img_size;
+
+void kernel_main(uint32_t r0, uint32_t r1, uint32_t atags)
+{
+ // stage2 of the bootloader is a blob embedded in executable;
+ // copy it over to it's destination place
+ // TODO implement a memcpy() somewhere and use it instead of loops
+ for (size_t i = 0; i < (size_t) &_binary_loader_stage2_img_size; i++)
+ stage2_addr[i] = (&_binary_loader_stage2_img_start)[i];
+
+ // jump to stage2
+ ((void(*)(uint32_t, uint32_t, uint32_t))stage2_addr)(r0, r1, atags);
+}