4 * Copyright (C) 2007 OpenWrt.org
5 * Copyright (C) 2007 Gabor Juhos <juhosg at openwrt.org>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the
19 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
24 #include <linux/init.h>
25 #include <linux/types.h>
26 #include <linux/kernel.h>
29 #include <asm/bootinfo.h>
30 #include <asm/addrspace.h>
32 #include <adm5120_info.h>
33 #include <adm5120_defs.h>
34 #include <adm5120_switch.h>
35 #include <adm5120_mpmc.h>
38 # define mem_dbg(f, a...) printk("mem_detect: " f, ## a)
40 # define mem_dbg(f, a...)
43 unsigned long adm5120_memsize
;
45 #define MEM_READL(a) __raw_readl((void __iomem *)(a))
46 #define MEM_WRITEL(a, v) __raw_writel((v), (void __iomem *)(a))
48 static int __init
mem_check_pattern(u8
*addr
, unsigned long offs
)
50 u32
*p1
= (u32
*)addr
;
51 u32
*p2
= (u32
*)(addr
+offs
);
54 /* save original value */
65 mem_dbg("write 0x%08X to 0x%08lX\n", v
, (unsigned long)p1
);
71 mem_dbg("pattern at 0x%08lX is 0x%08X\n", (unsigned long)p2
, u
);
73 /* restore original value */
79 static void __init
adm5120_detect_memsize(void)
85 memctrl
= SW_READ_REG(MEMCTRL
);
86 switch (memctrl
& MEMCTRL_SDRS_MASK
) {
93 case MEMCTRL_SDRS_16M
:
101 mem_dbg("checking for %uMB chip in 1st bank\n", maxsize
>> 20);
103 /* detect size of the 1st SDRAM bank */
104 p
= (u8
*)KSEG1ADDR(0);
105 for (size
= 2<<20; size
<= (maxsize
>> 1); size
<<= 1) {
106 if (mem_check_pattern(p
, size
)) {
107 /* mirrored address */
108 mem_dbg("mirrored data found at offset 0x%08X\n", size
);
113 mem_dbg("chip size in 1st bank is %uMB\n", size
>> 20);
114 adm5120_memsize
= size
;
117 /* 2nd bank is not supported */
120 if ((memctrl
& MEMCTRL_SDR1_ENABLE
) == 0)
121 /* 2nd bank is disabled */
125 * some bootloaders enable 2nd bank, even if the 2nd SDRAM chip
128 mem_dbg("check presence of 2nd bank\n");
130 p
= (u8
*)KSEG1ADDR(maxsize
+size
-4);
131 if (mem_check_pattern(p
, 0)) {
132 adm5120_memsize
+= size
;
135 if (maxsize
!= size
) {
136 /* adjusting MECTRL register */
137 memctrl
&= ~(MEMCTRL_SDRS_MASK
);
140 memctrl
|= MEMCTRL_SDRS_4M
;
143 memctrl
|= MEMCTRL_SDRS_8M
;
146 memctrl
|= MEMCTRL_SDRS_16M
;
149 memctrl
|= MEMCTRL_SDRS_64M
;
152 SW_WRITE_REG(MEMCTRL
, memctrl
);
156 mem_dbg("%dx%uMB memory found\n", (adm5120_memsize
== size
) ? 1 : 2 ,
160 void __init
adm5120_mem_init(void)
162 adm5120_detect_memsize();
163 add_memory_region(0, adm5120_memsize
, BOOT_MEM_RAM
);