xref: /linux/arch/mips/txx9/generic/mem_tx4927.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * common tx4927 memory interface
3  *
4  * Author: MontaVista Software, Inc.
5  *         source@mvista.com
6  *
7  * Copyright 2001-2002 MontaVista Software Inc.
8  *
9  *  This program is free software; you can redistribute it and/or modify it
10  *  under the terms of the GNU General Public License as published by the
11  *  Free Software Foundation; either version 2 of the License, or (at your
12  *  option) any later version.
13  *
14  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
15  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
16  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
19  *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
20  *  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
21  *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
22  *  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
23  *  USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  *  You should have received a copy of the GNU General Public License along
26  *  with this program; if not, write to the Free Software Foundation, Inc.,
27  *  675 Mass Ave, Cambridge, MA 02139, USA.
28  */
29 
30 #include <linux/init.h>
31 #include <linux/types.h>
32 #include <linux/io.h>
33 #include <asm/txx9/tx4927.h>
34 
35 static unsigned int __init tx4927_process_sdccr(u64 __iomem *addr)
36 {
37 	u64 val;
38 	unsigned int sdccr_ce;
39 	unsigned int sdccr_bs;
40 	unsigned int sdccr_rs;
41 	unsigned int sdccr_cs;
42 	unsigned int sdccr_mw;
43 	unsigned int bs = 0;
44 	unsigned int rs = 0;
45 	unsigned int cs = 0;
46 	unsigned int mw = 0;
47 
48 	val = __raw_readq(addr);
49 
50 	/* MVMCP -- need #defs for these bits masks */
51 	sdccr_ce = ((val & (1 << 10)) >> 10);
52 	sdccr_bs = ((val & (1 << 8)) >> 8);
53 	sdccr_rs = ((val & (3 << 5)) >> 5);
54 	sdccr_cs = ((val & (7 << 2)) >> 2);
55 	sdccr_mw = ((val & (1 << 0)) >> 0);
56 
57 	if (sdccr_ce) {
58 		bs = 2 << sdccr_bs;
59 		rs = 2048 << sdccr_rs;
60 		cs = 256 << sdccr_cs;
61 		mw = 8 >> sdccr_mw;
62 	}
63 
64 	return rs * cs * mw * bs;
65 }
66 
67 unsigned int __init tx4927_get_mem_size(void)
68 {
69 	unsigned int total = 0;
70 	int i;
71 
72 	for (i = 0; i < ARRAY_SIZE(tx4927_sdramcptr->cr); i++)
73 		total += tx4927_process_sdccr(&tx4927_sdramcptr->cr[i]);
74 	return total;
75 }
76