Hello, On Fri, Mar 04, 2011 at 10:47:56AM -0800, Kristen Carlson Accardi wrote: > > Why not just do the following? > > > > scontrol &= ~(0x3 << 8); > > because, the IPM value is meaningless if we have no devices, > so this is a wasted operation. What? You're trying to save one AND operation to a value which is already in register in libata powersave path? That's wrong on so many levels (it's not even a proper optimization, think about it). Just make it easier on the eyes. > This change was tested on Intel's Sandy Bridge platform. Your power > savings will depend on how many implemented ports you have, and how > many are not being used. For a system I tested with which had 2 ports > which I could turn off, I saved 300mW. Can you please test at least on a couple different hardware and make sure that the port can be brought back after put to sleep? ie. Verify that hotplug still works after min_power -> max_performance? Also, please add the test results in the patch description. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
