diff options
Diffstat (limited to 'arch/mips/bcm47xx/prom.c')
| -rw-r--r-- | arch/mips/bcm47xx/prom.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/arch/mips/bcm47xx/prom.c b/arch/mips/bcm47xx/prom.c index f6e9063cc4c2..8c155afb1299 100644 --- a/arch/mips/bcm47xx/prom.c +++ b/arch/mips/bcm47xx/prom.c @@ -1,6 +1,7 @@ /* * Copyright (C) 2004 Florian Schirmer <jolt@tuxbox.org> * Copyright (C) 2007 Aurelien Jarno <aurelien@aurel32.net> + * Copyright (C) 2010-2012 Hauke Mehrtens <hauke@hauke-m.de> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the @@ -27,6 +28,7 @@ #include <linux/types.h> #include <linux/kernel.h> #include <linux/spinlock.h> +#include <linux/smp.h> #include <asm/bootinfo.h> #include <asm/fw/cfe/cfe_api.h> #include <asm/fw/cfe/cfe_error.h> @@ -127,6 +129,8 @@ static __init void prom_init_mem(void) { unsigned long mem; unsigned long max; + unsigned long off; + struct cpuinfo_mips *c = ¤t_cpu_data; /* Figure out memory size by finding aliases. * @@ -143,18 +147,26 @@ static __init void prom_init_mem(void) * max contains the biggest possible address supported by the platform. * If the method wants to try something above we assume 128MB ram. */ - max = ((unsigned long)(prom_init) | ((128 << 20) - 1)); + off = (unsigned long)prom_init; + max = off | ((128 << 20) - 1); for (mem = (1 << 20); mem < (128 << 20); mem += (1 << 20)) { - if (((unsigned long)(prom_init) + mem) > max) { + if ((off + mem) > max) { mem = (128 << 20); printk(KERN_DEBUG "assume 128MB RAM\n"); break; } - if (*(unsigned long *)((unsigned long)(prom_init) + mem) == - *(unsigned long *)(prom_init)) + if (!memcmp(prom_init, prom_init + mem, 32)) break; } + /* Ignoring the last page when ddr size is 128M. Cached + * accesses to last page is causing the processor to prefetch + * using address above 128M stepping out of the ddr address + * space. + */ + if (c->cputype == CPU_74K && (mem == (128 << 20))) + mem -= 0x1000; + add_memory_region(0, mem, BOOT_MEM_RAM); } |