vmm: Early virtual memory manager definitions. WIP.

Signed-off-by: TunaCici <[email protected]>

Kernel/Include/Memory/Virtual.h

@@ -0,0 +1,79 @@
+/*
+ * Virtual memory manager for the ARMv8-A architecture
+ *
+ * References:
+ * https://developer.arm.com/documentation/den0024/a/The-Memory-Management-Unit
+ * https://github.com/ARM-software/u-boot/blob/master/arch/arm/include/asm/armv8/mmu.h
+ * https://lowenware.com/blog/aarch64-mmu-programming/
+ *
+ * Author: Tuna CICI
+ */
+
+#ifndef VIRTUAL_H
+#define VIRTUAL_H
+
+#include <stdint.h>
+
+#include "Memory/PageDef.h"
+
+/* Hardware page table definition */
+#define PTE_TYPE_MASK		(3 << 0)
+#define PTE_TYPE_FAULT		(0 << 0)
+#define PTE_TYPE_TABLE		(3 << 0)
+#define PTE_TYPE_PAGE		(3 << 0)
+#define PTE_TYPE_BLOCK		(1 << 0)
+#define PTE_TYPE_VALID		(1 << 0)
+
+#define PTE_TABLE_PXN		(1UL << 59)
+#define PTE_TABLE_XN		(1UL << 60)
+#define PTE_TABLE_AP		(1UL << 61)
+#define PTE_TABLE_NS		(1UL << 63)
+
+/* Block */
+#define PTE_BLOCK_MEMTYPE(x)	((x) << 2)
+#define PTE_BLOCK_NS            (1 << 5)
+#define PTE_BLOCK_NON_SHARE	(0 << 8)
+#define PTE_BLOCK_OUTER_SHARE	(2 << 8)
+#define PTE_BLOCK_INNER_SHARE	(3 << 8)
+#define PTE_BLOCK_AF		(1 << 10)
+#define PTE_BLOCK_NG		(1 << 11)
+#define PTE_BLOCK_PXN		(UL(1) << 53)
+#define PTE_BLOCK_UXN		(UL(1) << 54)
+
+/* AttrIndx[2:0] */
+#define PMD_ATTRINDX(t)		((t) << 2)
+#define PMD_ATTRINDX_MASK	(7 << 2)
+#define PMD_ATTRMASK		(PTE_BLOCK_PXN		| \
+				 PTE_BLOCK_UXN		| \
+				 PMD_ATTRINDX_MASK	| \
+				 PTE_TYPE_VALID)
+
+/* TCR flags */
+#define TCR_T0SZ(x)		((64 - (x)) << 0)
+#define TCR_IRGN_NC		(0 << 8)
+#define TCR_IRGN_WBWA		(1 << 8)
+#define TCR_IRGN_WT		(2 << 8)
+#define TCR_IRGN_WBNWA		(3 << 8)
+#define TCR_IRGN_MASK		(3 << 8)
+#define TCR_ORGN_NC		(0 << 10)
+#define TCR_ORGN_WBWA		(1 << 10)
+#define TCR_ORGN_WT		(2 << 10)
+#define TCR_ORGN_WBNWA		(3 << 10)
+#define TCR_ORGN_MASK		(3 << 10)
+#define TCR_SHARED_NON		(0 << 12)
+#define TCR_SHARED_OUTER	(2 << 12)
+#define TCR_SHARED_INNER	(3 << 12)
+#define TCR_TG0_4K		(0 << 14)
+#define TCR_TG0_64K		(1 << 14)
+#define TCR_TG0_16K		(2 << 14)
+#define TCR_EPD1_DISABLE	(1 << 23)
+
+#define TCR_EL1_RSVD		(1 << 31)
+#define TCR_EL2_RSVD		(1 << 31 | 1 << 23)
+#define TCR_EL3_RSVD		(1 << 31 | 1 << 23)
+
+inline void init_ttbr(void *ttbr0, void *ttbr1);
+inline void init_tcr(void);
+inline void init_mair(void);
+
+#endif /* VIRTUAL_H */

Kernel/Memory/Virtual.c

@@ -0,0 +1,42 @@
+/*
+ * Virtual memory manager for the ARMv8-A architecture
+ *
+ * References:
+ * https://developer.arm.com/documentation/den0024/a/The-Memory-Management-Unit
+ * https://github.com/ARM-software/u-boot/blob/master/arch/arm/include/asm/armv8/mmu.h
+ * https://lowenware.com/blog/aarch64-mmu-programming/
+ *
+ * Author: Tuna CICI
+ */
+
+#include <stdint.h>
+
+#include "ARM64/Machine.h"
+#include "LibKern/Console.h"
+
+#include "Memory/PageDef.h"
+#include "Memory/Virtual.h"
+
+inline void init_ttbr(void *ttbr0, void *ttbr1)
+{
+        /* TODO */ 
+
+        MRS("TTBR0_EL1", ttbr0);
+        MRS("TTBR1_EL1", ttbr1);
+}
+
+inline void init_tcr(void)
+{
+        /* TODO */
+        uint64_t tcr_el1 = 0;
+
+        MRS("TCR_EL1", tcr_el1);
+}
+
+inline void init_mair(void)
+{
+        /* TODO */
+        uint64_t mair_el1 = 0;
+
+        MRS("MAIR_EL1", mair_el1);
+}