On Thu, 27 Jan 2011, mihn leigh wrote: > Yes, you're right. As you said, MSR register contains the frequency > and voltage information of cpu. By writing the register, we can change > voltage as well (it's the information from intel datasheet). But, i > cannot find the detail of this register. > > BTW, what's the reason that MSR register can not be changed in OS > level? is it only possible to change in BIOS? Well, while we do provide users with enough rope to hang themselves as a regular friendly kernel service (especially if it is limited to root access), we usually refrain from giving them hand grenades with the safety pin removed... And sometimes the hardware does the same, and thus the notion of the write-once register was born. I don't think it is the case here, but... -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
