patch-1.3.45 linux/arch/ppc/kernel/mmu.h

• Lines: 160
• Date: Fri May 5 03:44:02 1995
• Orig file: v1.3.44/linux/arch/ppc/kernel/mmu.h
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.44/linux/arch/ppc/kernel/mmu.h linux/arch/ppc/kernel/mmu.h
@@ -0,0 +1,159 @@
+/*
+ * PowerPC memory management structures
+ */
+
+#ifndef _PPC_MMU_H_
+#define _PPC_MMU_H_
+
+/* Hardware Page Table Entry */
+ 
+typedef struct _PTE
+   {
+      unsigned long v:1;	/* Entry is valid */
+      unsigned long vsid:24;	/* Virtual segment identifier */
+      unsigned long h:1;	/* Hash algorithm indicator */
+      unsigned long api:6;	/* Abbreviated page index */
+      unsigned long rpn:20;	/* Real (physical) page number */
+      unsigned long    :3;	/* Unused */
+      unsigned long r:1;	/* Referenced */
+      unsigned long c:1;	/* Changed */
+      unsigned long w:1;	/* Write-thru cache mode */
+      unsigned long i:1;	/* Cache inhibited */
+      unsigned long m:1;	/* Memory coherence */
+      unsigned long g:1;	/* Guarded */
+      unsigned long    :1;	/* Unused */
+      unsigned long pp:2;	/* Page protection */
+   } PTE; 
+
+/* Values for PP (assumes Ks=0, Kp=1) */
+#define PP_RWXX	0	/* Supervisor read/write, User none */
+#define PP_RWRX 1	/* Supervisor read/write, User read */
+#define PP_RWRW 2	/* Supervisor read/write, User read/write */
+
+/* Segment Register */
+
+typedef struct _SEGREG
+   {
+      unsigned long t:1;	/* Normal or I/O  type */
+      unsigned long ks:1;	/* Supervisor 'key' (normally 0) */
+      unsigned long kp:1;	/* User 'key' (normally 1) */
+      unsigned long n:1;	/* No-execute */
+      unsigned long :4;		/* Unused */
+      unsigned long vsid:24;	/* Virtual Segment Identifier */
+   } SEGREG;
+
+/* Block Address Translation (BAT) Registers */
+
+typedef struct _BATU		/* Upper part of BAT */
+   {
+      unsigned long bepi:15;	/* Effective page index (virtual address) */
+      unsigned long :4;		/* Unused */
+      unsigned long bl:11;	/* Block size mask */
+      unsigned long vs:1;	/* Supervisor valid */
+      unsigned long vp:1;	/* User valid */
+   } BATU;   
+
+typedef struct _BATL		/* Lower part of BAT */
+   {
+      unsigned long brpn:15;	/* Real page index (physical address) */
+      unsigned long :10;	/* Unused */
+      unsigned long w:1;	/* Write-thru cache */
+      unsigned long i:1;	/* Cache inhibit */
+      unsigned long m:1;	/* Memory coherence */
+      unsigned long g:1;	/* Guarded (MBZ) */
+      unsigned long :1;		/* Unused */
+      unsigned long pp:2;	/* Page access protections */
+   } BATL;
+
+typedef struct _BAT
+   {
+      BATU batu;		/* Upper register */
+      BATL batl;		/* Lower register */
+   } BAT;
+
+/* Block size masks */
+#define BL_128K	0x000
+#define BL_256K 0x001
+#define BL_512K 0x003
+#define BL_1M   0x007
+#define BL_2M   0x00F
+#define BL_4M   0x01F
+#define BL_8M   0x03F
+#define BL_16M  0x07F
+#define BL_32M  0x0FF
+#define BL_64M  0x1FF
+#define BL_128M 0x3FF
+#define BL_256M 0x7FF
+
+/* BAT Access Protection */
+#define BPP_XX	0x00		/* No access */
+#define BPP_RX	0x01		/* Read only */
+#define BPP_RW	0x02		/* Read/write */
+
+/*
+ * Simulated two-level MMU.  This structure is used by the kernel
+ * to keep track of MMU mappings and is used to update/maintain
+ * the hardware HASH table which is really a cache of mappings.
+ *
+ * The simulated structures mimic the hardware available on other
+ * platforms, notably the 80x86 and 680x0.
+ */
+
+typedef struct _pte
+   {
+   	unsigned long page_num:20;
+   	unsigned long unused:6;
+   	unsigned long acc:3;		/* Read/write/execute permissions */
+   	unsigned long r:1;		/* Page has been referenced */
+   	unsigned long m:1;		/* Page has been modified */
+   	unsigned long v:1;		/* Entry is valid */
+   } pte;
+
+#define ACC_Rxx	0x04
+#define ACC_xWx 0x02
+#define ACC_xxX 0x01
+#define ACC_RWX (ACC_Rxx|ACC_xWx|ACC_xxX)
+
+#define PD_SHIFT (10+12)		/* Page directory */
+#define PD_MASK  0x02FF
+#define PT_SHIFT (12)			/* Page Table */
+#define PT_MASK  0x02FF
+#define PG_SHIFT (12)			/* Page Entry */
+ 
+
+/* MMU context */
+
+typedef struct _MMU_context
+   {
+      SEGREG	segs[16];	/* Segment registers */
+      pte	**pmap;		/* Two-level page-map structure */
+   } MMU_context;
+
+#if 0
+BAT	ibat[4];	/* Instruction BAT images */
+BAT	dbat[4];	/* Data BAT images */
+PTE	*hash_table;	/* Hardware hashed page table */
+int	hash_table_size;
+int	hash_table_mask;
+unsigned long sdr;	/* Hardware image of SDR */
+#endif   
+
+/* Used to set up SDR register */
+#define HASH_TABLE_SIZE_64K	0x00010000
+#define HASH_TABLE_SIZE_128K	0x00020000
+#define HASH_TABLE_SIZE_256K	0x00040000
+#define HASH_TABLE_SIZE_512K	0x00080000
+#define HASH_TABLE_SIZE_1M	0x00100000
+#define HASH_TABLE_SIZE_2M	0x00200000
+#define HASH_TABLE_SIZE_4M	0x00400000
+#define HASH_TABLE_MASK_64K	0x000   
+#define HASH_TABLE_MASK_128K	0x001   
+#define HASH_TABLE_MASK_256K	0x003   
+#define HASH_TABLE_MASK_512K	0x007
+#define HASH_TABLE_MASK_1M	0x00F   
+#define HASH_TABLE_MASK_2M	0x01F   
+#define HASH_TABLE_MASK_4M	0x03F   
+
+#define MMU_PAGE_SIZE	4096
+
+#endif