xref: /linux/arch/mips/txx9/generic/mem_tx4927.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
1 /*
2  * linux/arch/mips/txx9/generic/mem_tx4927.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/types.h>
34 #include <linux/io.h>
35 #include <asm/txx9/tx4927.h>
36 
37 static unsigned int __init tx4927_process_sdccr(u64 __iomem *addr)
38 {
39 	u64 val;
40 	unsigned int sdccr_ce;
41 	unsigned int sdccr_bs;
42 	unsigned int sdccr_rs;
43 	unsigned int sdccr_cs;
44 	unsigned int sdccr_mw;
45 	unsigned int bs = 0;
46 	unsigned int rs = 0;
47 	unsigned int cs = 0;
48 	unsigned int mw = 0;
49 
50 	val = __raw_readq(addr);
51 
52 	/* MVMCP -- need #defs for these bits masks */
53 	sdccr_ce = ((val & (1 << 10)) >> 10);
54 	sdccr_bs = ((val & (1 << 8)) >> 8);
55 	sdccr_rs = ((val & (3 << 5)) >> 5);
56 	sdccr_cs = ((val & (7 << 2)) >> 2);
57 	sdccr_mw = ((val & (1 << 0)) >> 0);
58 
59 	if (sdccr_ce) {
60 		bs = 2 << sdccr_bs;
61 		rs = 2048 << sdccr_rs;
62 		cs = 256 << sdccr_cs;
63 		mw = 8 >> sdccr_mw;
64 	}
65 
66 	return rs * cs * mw * bs;
67 }
68 
69 unsigned int __init tx4927_get_mem_size(void)
70 {
71 	unsigned int total = 0;
72 	int i;
73 
74 	for (i = 0; i < ARRAY_SIZE(tx4927_sdramcptr->cr); i++)
75 		total += tx4927_process_sdccr(&tx4927_sdramcptr->cr[i]);
76 	return total;
77 }
78