[ARM] 4845/1: Orion: Ignore memory tags with invalid data

The DNS-323, Kurobox-Pro / Linkstation-Pro, QNAP TS-109/TS-209 and some
other orion-based systems have several bogus memory entries in the tag
table, which causes the system to crash at startup. Ignore them by
resetting the tag ID to 0 in a machine fixup function.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-orion/common.c

@@ -17,7 +17,9 @@
 #include <linux/mv643xx_eth.h>
 #include <linux/mv643xx_i2c.h>
 #include <asm/page.h>
+#include <asm/setup.h>
 #include <asm/timex.h>
+#include <asm/mach/arch.h>
 #include <asm/mach/map.h>
 #include <asm/arch/hardware.h>
 #include "common.h"
@@ -347,3 +349,21 @@ void __init orion_init(void)
 		platform_device_register(&orion_ehci1);
 	platform_device_register(&orion_i2c);
 }
+
+/*
+ * Many orion-based systems have buggy bootloader implementations.
+ * This is a common fixup for bogus memory tags.
+ */
+void __init tag_fixup_mem32(struct machine_desc *mdesc, struct tag *t,
+			    char **from, struct meminfo *meminfo)
+{
+	for (; t->hdr.size; t = tag_next(t))
+		if (t->hdr.tag == ATAG_MEM &&
+		    (!t->u.mem.size || t->u.mem.size & ~PAGE_MASK ||
+		     t->u.mem.start & ~PAGE_MASK)) {
+			printk(KERN_WARNING
+			       "Clearing invalid memory bank %dKB@0x%08x\n",
+			       t->u.mem.size / 1024, t->u.mem.start);
+			t->hdr.tag = 0;
+		}
+}

arch/arm/mach-orion/common.h

@@ -83,4 +83,10 @@ struct mv_sata_platform_data;
 
 void __init orion_sata_init(struct mv_sata_platform_data *sata_data);
 
+struct machine_desc;
+struct meminfo;
+struct tag;
+extern void __init tag_fixup_mem32(struct machine_desc *, struct tag *,
+				   char **, struct meminfo *);
+
 #endif /* __ARCH_ORION_COMMON_H__ */

arch/arm/mach-orion/dns323-setup.c

@@ -319,4 +319,5 @@ MACHINE_START(DNS323, "D-Link DNS-323")
 	.map_io		= orion_map_io,
 	.init_irq	= orion_init_irq,
 	.timer		= &orion_timer,
+	.fixup		= tag_fixup_mem32,
 MACHINE_END

arch/arm/mach-orion/kurobox_pro-setup.c

@@ -240,4 +240,5 @@ MACHINE_START(KUROBOX_PRO, "Buffalo/Revogear Kurobox Pro")
 	.map_io		= orion_map_io,
 	.init_irq	= orion_init_irq,
 	.timer		= &orion_timer,
+	.fixup		= tag_fixup_mem32,
 MACHINE_END

arch/arm/mach-orion/ts209-setup.c

@@ -357,4 +357,5 @@ MACHINE_START(TS209, "QNAP TS-109/TS-209")
 	.map_io		= orion_map_io,
 	.init_irq	= orion_init_irq,
 	.timer		= &orion_timer,
+	.fixup		= tag_fixup_mem32,
 MACHINE_END