xref: /plan9/sys/src/9/pc/mem.h (revision a3fbd16063946e19237285db486672a21b4a1977)
1 /*
2  * Memory and machine-specific definitions.  Used in C and assembler.
3  */
4 
5 #define MIN(a, b)	((a) < (b)? (a): (b))
6 #define MAX(a, b)	((a) > (b)? (a): (b))
7 
8 /*
9  * Sizes
10  */
11 #define	BI2BY		8			/* bits per byte */
12 #define	BI2WD		32			/* bits per word */
13 #define	BY2WD		4			/* bytes per word */
14 #define	BY2V		8			/* bytes per double word */
15 #define	BY2PG		4096			/* bytes per page */
16 #define	WD2PG		(BY2PG/BY2WD)		/* words per page */
17 #define	BY2XPG		(4096*1024)		/* bytes per big page */
18 #define	PGSHIFT		12			/* log(BY2PG) */
19 #define	ROUND(s, sz)	(((s)+((sz)-1))&~((sz)-1))
20 #define	PGROUND(s)	ROUND(s, BY2PG)
21 #define CACHELINESZ	32			/* pentium & later */
22 #define	BLOCKALIGN	8
23 #define FPalign		16			/* required for FXSAVE */
24 
25 /*
26  * In 32-bit mode, the MAXMACH limit is 32 without
27  * changing the way active.machs is defined and used
28  * (unfortunately, it is also used in the port code).
29  */
30 #define	MAXMACH		32			/* max # cpus system can run */
31 #define	KSTACK		4096			/* Size of kernel stack */
32 
33 /*
34  * Time
35  */
36 #define	HZ		(100)			/* clock frequency */
37 #define	MS2HZ		(1000/HZ)		/* millisec per clock tick */
38 #define	TK2SEC(t)	((t)/HZ)		/* ticks to seconds */
39 
40 /*
41  *  Address spaces
42  */
43 #define	KZERO		0xF0000000		/* base of kernel address space */
44 #define	KTZERO		(KZERO+0x100000)	/* first address in kernel text - 9load sits below */
45 #define	VPT		(KZERO-VPTSIZE)
46 #define	VPTSIZE		BY2XPG
47 #define	NVPT		(VPTSIZE/BY2WD)
48 #define	KMAP		(VPT-KMAPSIZE)
49 #define	KMAPSIZE	BY2XPG
50 #define	VMAP		(KMAP-VMAPSIZE)
51 #define	VMAPSIZE	(0x10000000-VPTSIZE-KMAPSIZE)
52 #define	UZERO		0			/* base of user address space */
53 #define	UTZERO		(UZERO+BY2PG)		/* first address in user text */
54 #define	USTKTOP		(VMAP-BY2PG)		/* byte just beyond user stack */
55 #define	USTKSIZE	(16*1024*1024)		/* size of user stack */
56 #define	TSTKTOP		(USTKTOP-USTKSIZE)	/* end of new stack in sysexec */
57 #define	TSTKSIZ 	100			/* pages in new stack; limits exec args */
58 
59 /*
60  * Fundamental addresses - bottom 64kB saved for return to real mode
61  */
62 #define	CONFADDR	(KZERO+0x1200)		/* info passed from boot loader */
63 #define	TMPADDR		(KZERO+0x2000)		/* used for temporary mappings */
64 #define	APBOOTSTRAP	(KZERO+0x3000)		/* AP bootstrap code */
65 #define	RMUADDR		(KZERO+0x7C00)		/* real mode Ureg */
66 #define	RMCODE		(KZERO+0x8000)		/* copy of first page of KTEXT */
67 #define	RMBUF		(KZERO+0x9000)		/* buffer for user space - known to vga */
68 #define	IDTADDR		(KZERO+0x10800)		/* idt */
69 #define	REBOOTADDR	(0x11000)		/* reboot code - physical address */
70 #define	CPU0PDB		(KZERO+0x12000)		/* bootstrap processor PDB */
71 #define	CPU0PTE		(KZERO+0x13000)		/* bootstrap processor PTE's for 0-4MB */
72 #define	CPU0GDT		(KZERO+0x14000)		/* bootstrap processor GDT */
73 #define	MACHADDR	(KZERO+0x15000)		/* as seen by current processor */
74 #define	CPU0MACH	(KZERO+0x16000)		/* Mach for bootstrap processor */
75 #define	MACHSIZE	BY2PG
76 #define CPU0PTE1	(KZERO+0x17000)		/* bootstrap processor PTE's for 4MB-8MB */
77 #define CPU0END		(CPU0PTE1+BY2PG)
78 /*
79  * N.B.  ramscan knows that CPU0END is the end of reserved data
80  * N.B.  _startPADDR knows that CPU0PDB is the first reserved page
81  * and that there are 6 of them.
82  */
83 
84 /*
85  *  known x86 segments (in GDT) and their selectors
86  */
87 #define	NULLSEG	0	/* null segment */
88 #define	KDSEG	1	/* kernel data/stack */
89 #define	KESEG	2	/* kernel executable */
90 #define	UDSEG	3	/* user data/stack */
91 #define	UESEG	4	/* user executable */
92 #define	TSSSEG	5	/* task segment */
93 #define	APMCSEG		6	/* APM code segment */
94 #define	APMCSEG16	7	/* APM 16-bit code segment */
95 #define	APMDSEG		8	/* APM data segment */
96 #define	KESEG16		9	/* kernel executable 16-bit */
97 #define	NGDT		10	/* number of GDT entries required */
98 /* #define	APM40SEG	8	/* APM segment 0x40 */
99 
100 #define	SELGDT	(0<<2)	/* selector is in gdt */
101 #define	SELLDT	(1<<2)	/* selector is in ldt */
102 
103 #define	SELECTOR(i, t, p)	(((i)<<3) | (t) | (p))
104 
105 #define	NULLSEL	SELECTOR(NULLSEG, SELGDT, 0)
106 #define	KDSEL	SELECTOR(KDSEG, SELGDT, 0)
107 #define	KESEL	SELECTOR(KESEG, SELGDT, 0)
108 #define	UESEL	SELECTOR(UESEG, SELGDT, 3)
109 #define	UDSEL	SELECTOR(UDSEG, SELGDT, 3)
110 #define	TSSSEL	SELECTOR(TSSSEG, SELGDT, 0)
111 #define	APMCSEL 	SELECTOR(APMCSEG, SELGDT, 0)
112 #define	APMCSEL16	SELECTOR(APMCSEG16, SELGDT, 0)
113 #define	APMDSEL		SELECTOR(APMDSEG, SELGDT, 0)
114 /* #define	APM40SEL	SELECTOR(APM40SEG, SELGDT, 0) */
115 
116 /*
117  *  fields in segment descriptors
118  */
119 #define	SEGDATA	(0x10<<8)	/* data/stack segment */
120 #define	SEGEXEC	(0x18<<8)	/* executable segment */
121 #define	SEGTSS	(0x9<<8)	/* TSS segment */
122 #define	SEGCG	(0x0C<<8)	/* call gate */
123 #define	SEGIG	(0x0E<<8)	/* interrupt gate */
124 #define	SEGTG	(0x0F<<8)	/* trap gate */
125 #define	SEGTYPE	(0x1F<<8)
126 
127 #define	SEGP	(1<<15)		/* segment present */
128 #define	SEGPL(x) ((x)<<13)	/* priority level */
129 #define	SEGB	(1<<22)		/* granularity 1==4k (for expand-down) */
130 #define	SEGG	(1<<23)		/* granularity 1==4k (for other) */
131 #define	SEGE	(1<<10)		/* expand down */
132 #define	SEGW	(1<<9)		/* writable (for data/stack) */
133 #define	SEGR	(1<<9)		/* readable (for code) */
134 #define	SEGD	(1<<22)		/* default 1==32bit (for code) */
135 
136 /*
137  *  virtual MMU
138  */
139 #define	PTEMAPMEM	(1024*1024)
140 #define	PTEPERTAB	(PTEMAPMEM/BY2PG)
141 #define	SEGMAPSIZE	1984
142 #define	SSEGMAPSIZE	16
143 #define	PPN(x)		((x)&~(BY2PG-1))
144 
145 /*
146  *  physical MMU
147  */
148 #define	PTEVALID	(1<<0)
149 #define	PTEWT		(1<<3)
150 #define	PTEUNCACHED	(1<<4)
151 #define	PTEWRITE	(1<<1)
152 #define	PTERONLY	(0<<1)
153 #define	PTEKERNEL	(0<<2)
154 #define	PTEUSER		(1<<2)
155 #define	PTESIZE		(1<<7)
156 #define	PTEGLOBAL	(1<<8)
157 
158 /*
159  * Macros for calculating offsets within the page directory base
160  * and page tables.
161  */
162 #define	PDX(va)		((((ulong)(va))>>22) & 0x03FF)
163 #define	PTX(va)		((((ulong)(va))>>12) & 0x03FF)
164 
165 #define	getpgcolor(a)	0
166 
167