Greg KH <gregkh@xxxxxxx> writes: > On Mon, Oct 10, 2011 at 07:31:26PM +0200, Mikael Pettersson wrote: >> Greg KH writes: >> > On Mon, Oct 10, 2011 at 05:29:13PM +0100, Måns Rullgård wrote: >> > > Greg KH <gregkh@xxxxxxx> writes: >> > > >> > > > On Mon, Oct 10, 2011 at 02:38:27PM +0200, Harro Haan wrote: >> > > >> The Kirkwood gave an unaligned memory access error on >> > > >> line 742 of drivers/usb/host/echi-hcd.c: >> > > >> "ehci->last_periodic_enable = ktime_get_real();" >> > > > >> > > > What is "The Kirkwood"? What size processor is this? >> > > >> > > It's an ARM926-like CPU from Marvell. >> > >> > 32 or 64bit? >> >> All ARMs are 32-bit, but some have instructions for loading or >> storing 2 x 32 bits at a time, but also require the corresponding >> memory address to be 64-bit aligned. To be perfectly accurate, all ARMs have the dual load/store instructions, but only some (ARMv5 and earlier) require a 64-bit aligned address for these. The Kirkwood is an ARMv5 so it does need this alignment. Furthermore, the standard ARM ABI requires 8-byte alignment for 64-bit data types regardless of CPU version, which is perhaps a bit unusual for a 32-bit architecture. -- Måns Rullgård mans@xxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
