Decoupling Architectural-specific Code (#35)

[lunaix-os.git] / lunaix-os / arch / generic / includes / sys / mm / mm_defs.h

diff --git a/lunaix-os/arch/generic/includes/sys/mm/mm_defs.h b/lunaix-os/arch/generic/includes/sys/mm/mm_defs.h
new file mode 100644 (file)
index 0000000..79ce14c
--- /dev/null
+++ b/lunaix-os/arch/generic/includes/sys/mm/mm_defs.h
@@ -0,0 +1,34 @@
+#ifndef __LUNAIX_MM_DEFS_H
+#define __LUNAIX_MM_DEFS_H
+
+
+#include "mempart.h"
+#include "pagetable.h"
+
+#define KSTACK_PAGES            3
+#define KSTACK_SIZE             (KSTACK_PAGES * MEM_PAGE)
+
+/*
+    Regardless architecture we need to draw the line very carefully, and must 
+    take the size of VM into account. In general, we aims to achieve 
+    "sufficiently large" of memory for kernel
+
+    In terms of x86_32:
+        * #768~1022 PTEs of PD      (0x00000000c0000000, ~1GiB)
+    
+    In light of upcomming x86_64 support (for Level 4&5 Paging):
+        * #510 entry of PML4        (0x0000ff0000000000, ~512GiB)
+        * #510 entry of PML5        (0x01fe000000000000, ~256TiB)
+*/
+// Where the kernel getting re-mapped.
+#define KERNEL_RESIDENT         0x0
+
+// Pages reserved for kernel image
+#define KEXEC_RSVD              16
+
+#define kernel_addr(addr)       (addr)
+
+#define to_kphysical(k_va)      ((ptr_t)(k_va))
+#define to_kvirtual(k_pa)       ((ptr_t)(k_pa))
+
+#endif /* __LUNAIX_MM_DEFS_H */