xref: /netbsd-src/sys/arch/evbppc/virtex/dcr.h (revision cc01a7f7c9782f04aca6a4427c47953edf7bd7b2)
1 /* 	$NetBSD: dcr.h,v 1.3 2022/03/10 00:14:16 riastradh Exp $ */
2 
3 /*
4  * Copyright (c) 2006 Jachym Holecek
5  * All rights reserved.
6  *
7  * Written for DFC Design, s.r.o.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * DCR is an user accessible bus on Xilinx PPC405D5Xn cores and may contain
34  * arbitrary devices. Because we want to be able to share drivers with
35  * OPB/PLB, we make it a bus space backend. Each platform ("design", "board")
36  * has to provide the leaf _read_4/_write_4 routines specific to device
37  * instances. This is dictated by the fact that DCR can only by accessed
38  * by m{f,t}dcr instructions for which the address is encoded as immediate
39  * operand (and hence needs to be a compile-time constant).
40  *
41  * The flexibility is well worth the price of one indirection (and a sum
42  * and a branch), critical paths can still be implemented with m{f,t}dcr().
43  */
44 
45 #ifndef _VIRTEX_DCRVAR_H_
46 #define _VIRTEX_DCRVAR_H_
47 
48 
49 /* From evbppc/virtex/machdep.c */
50 int 	dcr_subregion(bus_space_tag_t, bus_space_handle_t, bus_size_t,
51 	    bus_size_t, bus_space_handle_t *);
52 int 	dcr_map(bus_space_tag_t, bus_addr_t, bus_size_t, int,
53 	    bus_space_handle_t *);
54 void 	dcr_unmap(bus_space_tag_t, bus_space_handle_t, bus_size_t);
55 void	dcr_barrier(bus_space_tag_t, bus_space_handle_t, bus_size_t,
56 	    bus_size_t, int);
57 
58 /* Bus space tag contents, one tag per DCR device. */
59 #define DCR_BST_BODY(base, read, write) \
60 	.pbs_flags 		= _BUS_SPACE_BIG_ENDIAN, 	\
61 	.pbs_offset 		= 0, 				\
62 	.pbs_base 		= (base), 			\
63 	.pbs_limit 		= 0x03ff, 			\
64 	.pbs_scalar 		= { 				\
65 		.pbss_write_4 	= (write), 			\
66 		.pbss_read_4 	= (read), 			\
67 	}, 							\
68 	.pbs_map 		= dcr_map, 			\
69 	.pbs_unmap 		= dcr_unmap, 			\
70 	.pbs_subregion 		= dcr_subregion,
71 
72 /*
73  * Utility macros for leaf access routines. Note they assume variables
74  * in local scope, and are furthermore assumed to be used in switch()
75  * dispatch over destination address.
76  */
77 #define WCASE(base, addr) \
78     case (addr): mtdcr((base) + (addr) / 4, val); break
79 
80 #define WDEAD(addr) \
81     default: panic("%s: unexpected offset %#08x", __func__, (addr))
82 
83 #define RCASE(base, addr) \
84     case (addr): val = mfdcr((base) + (addr) / 4); break
85 
86 #define RDEAD(addr) \
87     default: panic("%s: unexpected offset %#08x", __func__, (addr))
88 
89 #endif /* _VIRTEX_DCRVAR_H_ */
90