Hi, Looks like the register offsets are incorrect in the OMAP mailbox code (arch/arm/mach-omap2/mailbox.c) for the OMAP4_MAILBOX_IRQ* macros. The discrepancy is with p.224 of TI document SPRUGX9 and p3891 of SWPU231K. Patch attached. My hardware hasn't come in yet, so I would appreciate it if anyone can share their experience using this code. Thanks. -H -- Henry Chan