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

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@33598 3c298f89-4303-0410-b956-a3cf2f4a3e73
2012-09-30 11:43:40 +00:00 · 2012-09-30 11:43:40 +00:00 · 7d525bd21f
parent 3d85f4a79f
commit 7d525bd21f
1 changed files with 33 additions and 0 deletions
--- 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
@ -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);
+ }
+