xref: /openbsd/sys/arch/alpha/include/pcb.h (revision 2df12b22)
1 /*	$OpenBSD: pcb.h,v 1.11 2015/05/05 02:13:46 guenther Exp $	*/
2 /*	$NetBSD: pcb.h,v 1.5 1996/11/13 22:21:00 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
6  * All rights reserved.
7  *
8  * Author: Chris G. Demetriou
9  *
10  * Permission to use, copy, modify and distribute this software and
11  * its documentation is hereby granted, provided that both the copyright
12  * notice and this permission notice appear in all copies of the
13  * software, derivative works or modified versions, and any portions
14  * thereof, and that both notices appear in supporting documentation.
15  *
16  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
18  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19  *
20  * Carnegie Mellon requests users of this software to return to
21  *
22  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23  *  School of Computer Science
24  *  Carnegie Mellon University
25  *  Pittsburgh PA 15213-3890
26  *
27  * any improvements or extensions that they make and grant Carnegie the
28  * rights to redistribute these changes.
29  */
30 
31 #ifndef _MACHINE_PCB_H_
32 #define _MACHINE_PCB_H_
33 
34 #include <machine/frame.h>
35 #include <machine/reg.h>
36 
37 #include <machine/alpha_cpu.h>
38 
39 /*
40  * PCB: process control block
41  *
42  * In this case, the hardware structure that is the defining element
43  * for a process, and the additional state that must be saved by software
44  * on a context switch.  Fields marked [HW] are mandated by hardware; fields
45  * marked [SW] are for the software.
46  *
47  * It's said in the VMS PALcode section of the AARM that the pcb address
48  * passed to the swpctx PALcode call has to be a physical address.  Not
49  * knowing this (and trying a virtual) address proved this correct.
50  * So we cache the physical address of the pcb in the md_proc struct.
51  */
52 struct pcb {
53 	struct alpha_pcb pcb_hw;		/* PALcode defined */
54 	unsigned long	pcb_context[9];		/* s[0-6], ra, ps	[SW] */
55 	struct fpreg	pcb_fp;			/* FP registers		[SW] */
56 	unsigned long	pcb_onfault;		/* for copy faults	[SW] */
57 	struct cpu_info *volatile pcb_fpcpu;	/* CPU with our FP state[SW] */
58 };
59 
60 #ifdef _KERNEL
61 void savectx(struct pcb *);
62 #endif
63 
64 #endif /* _MACHINE_PCB_H_ */
65