1 /*
2  * linux/arch/mips/tx4927/common/tx4927_prom.c
3  *
4  * common tx4927 memory interface
5  *
6  * Author: MontaVista Software, Inc.
7  *         source@mvista.com
8  *
9  * Copyright 2001-2002 MontaVista Software Inc.
10  *
11  *  This program is free software; you can redistribute it and/or modify it
12  *  under the terms of the GNU General Public License as published by the
13  *  Free Software Foundation; either version 2 of the License, or (at your
14  *  option) any later version.
15  *
16  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
17  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  *  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23  *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
24  *  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
25  *  USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  *  You should have received a copy of the GNU General Public License along
28  *  with this program; if not, write to the Free Software Foundation, Inc.,
29  *  675 Mass Ave, Cambridge, MA 02139, USA.
30  */
31 
32 #include <linux/init.h>
33 #include <linux/mm.h>
34 #include <linux/sched.h>
35 #include <linux/bootmem.h>
36 
37 #include <asm/addrspace.h>
38 #include <asm/bootinfo.h>
39 #include <asm/tx4927/tx4927.h>
40 
tx4927_process_sdccr(u64 * addr)41 static unsigned int __init tx4927_process_sdccr(u64 * addr)
42 {
43 	u64 val;
44 	unsigned int sdccr_ce;
45 	unsigned int sdccr_bs;
46 	unsigned int sdccr_rs;
47 	unsigned int sdccr_cs;
48 	unsigned int sdccr_mw;
49 	unsigned int bs = 0;
50 	unsigned int rs = 0;
51 	unsigned int cs = 0;
52 	unsigned int mw = 0;
53 	unsigned int msize = 0;
54 
55 	val = (*((vu64 *) (addr)));
56 
57 	/* MVMCP -- need #defs for these bits masks */
58 	sdccr_ce = ((val & (1 << 10)) >> 10);
59 	sdccr_bs = ((val & (1 << 8)) >> 8);
60 	sdccr_rs = ((val & (3 << 5)) >> 5);
61 	sdccr_cs = ((val & (3 << 2)) >> 2);
62 	sdccr_mw = ((val & (1 << 0)) >> 0);
63 
64 	if (sdccr_ce) {
65 		switch (sdccr_bs) {
66 		case 0:{
67 				bs = 2;
68 				break;
69 			}
70 		case 1:{
71 				bs = 4;
72 				break;
73 			}
74 		}
75 		switch (sdccr_rs) {
76 		case 0:{
77 				rs = 2048;
78 				break;
79 			}
80 		case 1:{
81 				rs = 4096;
82 				break;
83 			}
84 		case 2:{
85 				rs = 8192;
86 				break;
87 			}
88 		case 3:{
89 				rs = 0;
90 				break;
91 			}
92 		}
93 		switch (sdccr_cs) {
94 		case 0:{
95 				cs = 256;
96 				break;
97 			}
98 		case 1:{
99 				cs = 512;
100 				break;
101 			}
102 		case 2:{
103 				cs = 1024;
104 				break;
105 			}
106 		case 3:{
107 				cs = 2048;
108 				break;
109 			}
110 		}
111 		switch (sdccr_mw) {
112 		case 0:{
113 				mw = 8;
114 				break;
115 			}	/* 8 bytes = 64 bits */
116 		case 1:{
117 				mw = 4;
118 				break;
119 			}	/* 4 bytes = 32 bits */
120 		}
121 	}
122 
123 	/*            bytes per chip     MB per chip      num chips */
124 	msize = (((rs * cs * mw) / (1024 * 1024)) * bs);
125 
126 	return (msize);
127 }
128 
129 
tx4927_get_mem_size(void)130 unsigned int __init tx4927_get_mem_size(void)
131 {
132 	unsigned int c0;
133 	unsigned int c1;
134 	unsigned int c2;
135 	unsigned int c3;
136 	unsigned int total;
137 
138 	/* MVMCP -- need #defs for these registers */
139 	c0 = tx4927_process_sdccr((u64 *) 0xff1f8000);
140 	c1 = tx4927_process_sdccr((u64 *) 0xff1f8008);
141 	c2 = tx4927_process_sdccr((u64 *) 0xff1f8010);
142 	c3 = tx4927_process_sdccr((u64 *) 0xff1f8018);
143 	total = c0 + c1 + c2 + c3;
144 
145 	return (total);
146 }
147