--- linux-2.6.22.14/arch/mips/rb/rb500/latch.c	1970-01-01 03:00:00.000000000 +0300
+++ linux/arch/mips/rb/rb500/latch.c	2008-01-21 13:42:46.000000000 +0200
@@ -0,0 +1,51 @@
+#include <linux/init.h>
+#include <linux/miscdevice.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <asm/uaccess.h>
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <asm/rb/rb500.h>
+
+#define IDT434_REG_BASE ((volatile void *) KSEG1ADDR(0x18000000))
+
+unsigned char rb500_latch_state = RB500_LO_NCE | RB500_LO_FOFF;
+unsigned rb500_latch_addr;
+
+void set434Reg(unsigned regOffs, unsigned bit, unsigned len, unsigned val)
+{
+	unsigned flags, data;
+	unsigned i = 0;
+
+	local_irq_save(flags);
+
+	data = *(volatile unsigned *) (IDT434_REG_BASE + regOffs);
+	for (i = 0; i != len; ++i) {
+		if (val & (1 << i)) data |= (1 << (i + bit));
+		else data &= ~(1 << (i + bit));
+	}
+	*(volatile unsigned *) (IDT434_REG_BASE + regOffs) = data;
+
+	local_irq_restore(flags);
+}
+
+void changeLatchU5(unsigned char orMask, unsigned char nandMask)
+{
+	unsigned flags;
+
+	local_irq_save(flags);
+
+	rb500_latch_state = (rb500_latch_state | orMask) & ~nandMask;
+	writeb(rb500_latch_state, (void *) rb500_latch_addr);
+
+	local_irq_restore(flags);
+}
+
+void __init rb500_init_latch(void)
+{
+	rb500_latch_addr = KSEG1ADDR(inl(0x18010030));
+	writeb(rb500_latch_state, (void *) rb500_latch_addr);
+}
+
+EXPORT_SYMBOL(set434Reg);
+EXPORT_SYMBOL(changeLatchU5);