[brcm47xx]: ignore the last page on bcma based SoCs

SVN-Revision: 33598

diff --git a/target/linux/brcm47xx/patches-3.3/191-MIPS-BCM47XX-ignore-last-memory-page.patch b/target/linux/brcm47xx/patches-3.3/191-MIPS-BCM47XX-ignore-last-memory-page.patch
new file mode 100644 (file)
index 0000000..9f7d5dc
--- /dev/null
+++ b/target/linux/brcm47xx/patches-3.3/191-MIPS-BCM47XX-ignore-last-memory-page.patch
@@ -0,0 +1,33 @@
+--- a/arch/mips/bcm47xx/prom.c
++++ b/arch/mips/bcm47xx/prom.c
+@@ -27,6 +27,7 @@
+ #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>
+@@ -59,6 +60,7 @@ static __init void prom_init_mem(void)
+ {
+       unsigned long mem;
+       unsigned long max;
++      struct cpuinfo_mips *c = &current_cpu_data;
+ 
+       /* Figure out memory size by finding aliases.
+        *
+@@ -87,6 +89,14 @@ static __init void prom_init_mem(void)
+                       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);
+ }
+