2 * Copyright (C) 2007-2008 Gabor Juhos <juhosg@openwrt.org>
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 as published
6 * by the Free Software Foundation.
10 #include <linux/init.h>
11 #include <linux/types.h>
12 #include <linux/kernel.h>
15 #include <asm/bootinfo.h>
16 #include <asm/addrspace.h>
18 #include <asm/mach-adm5120/adm5120_info.h>
19 #include <asm/mach-adm5120/adm5120_defs.h>
20 #include <asm/mach-adm5120/adm5120_switch.h>
21 #include <asm/mach-adm5120/adm5120_mpmc.h>
24 # define mem_dbg(f, a...) printk(KERN_INFO "mem_detect: " f, ## a)
26 # define mem_dbg(f, a...)
29 unsigned long adm5120_memsize
;
31 #define MEM_READL(a) __raw_readl((void __iomem *)(a))
32 #define MEM_WRITEL(a, v) __raw_writel((v), (void __iomem *)(a))
34 static int __init
mem_check_pattern(u8
*addr
, unsigned long offs
)
36 u32
*p1
= (u32
*)addr
;
37 u32
*p2
= (u32
*)(addr
+offs
);
40 /* save original value */
51 mem_dbg("write 0x%08X to 0x%08lX\n", v
, (unsigned long)p1
);
57 mem_dbg("pattern at 0x%08lX is 0x%08X\n", (unsigned long)p2
, u
);
59 /* restore original value */
65 static void __init
adm5120_detect_memsize(void)
71 memctrl
= SW_READ_REG(SWITCH_REG_MEMCTRL
);
72 switch (memctrl
& MEMCTRL_SDRS_MASK
) {
79 case MEMCTRL_SDRS_16M
:
87 mem_dbg("checking for %uMB chip in 1st bank\n", maxsize
>> 20);
89 /* detect size of the 1st SDRAM bank */
90 p
= (u8
*)KSEG1ADDR(0);
91 for (size
= 2<<20; size
<= (maxsize
>> 1); size
<<= 1) {
92 if (mem_check_pattern(p
, size
)) {
93 /* mirrored address */
94 mem_dbg("mirrored data found at offset 0x%08X\n", size
);
99 mem_dbg("chip size in 1st bank is %uMB\n", size
>> 20);
100 adm5120_memsize
= size
;
103 /* 2nd bank is not supported */
106 if ((memctrl
& MEMCTRL_SDR1_ENABLE
) == 0)
107 /* 2nd bank is disabled */
111 * some bootloaders enable 2nd bank, even if the 2nd SDRAM chip
114 mem_dbg("check presence of 2nd bank\n");
116 p
= (u8
*)KSEG1ADDR(maxsize
+size
-4);
117 if (mem_check_pattern(p
, 0))
118 adm5120_memsize
+= size
;
120 if (maxsize
!= size
) {
121 /* adjusting MECTRL register */
122 memctrl
&= ~(MEMCTRL_SDRS_MASK
);
125 memctrl
|= MEMCTRL_SDRS_4M
;
128 memctrl
|= MEMCTRL_SDRS_8M
;
131 memctrl
|= MEMCTRL_SDRS_16M
;
134 memctrl
|= MEMCTRL_SDRS_64M
;
137 SW_WRITE_REG(SWITCH_REG_MEMCTRL
, memctrl
);
141 mem_dbg("%dx%uMB memory found\n", (adm5120_memsize
== size
) ? 1 : 2 ,
145 void __init
adm5120_mem_init(void)
147 adm5120_detect_memsize();
148 add_memory_region(0, adm5120_memsize
, BOOT_MEM_RAM
);