On Mon, Apr 22, 2013 at 01:43:29AM +0200, Rafael J. Wysocki wrote: > On Friday, April 19, 2013 07:00:57 PM Zhao Chenhui wrote: > > ----- Forwarded message from Zhao Chenhui <chenhui.zhao@xxxxxxxxxxxxx> ----- > > > > Date: Fri, 19 Apr 2013 18:47:39 +0800 > > From: Zhao Chenhui <chenhui.zhao@xxxxxxxxxxxxx> > > To: linuxppc-dev@xxxxxxxxxxxxxxxx > > CC: linux-kernel@xxxxxxxxxxxxxxx > > Subject: [linuxppc-release] [PATCH v2 06/15] powerpc/85xx: add support to JOG feature using cpufreq interface > > X-Mailer: git-send-email 1.7.3 > > > > From: chenhui zhao <chenhui.zhao@xxxxxxxxxxxxx> > > > > Some 85xx silicons like MPC8536 and P1022 have a JOG feature, which provides > > a dynamic mechanism to lower or raise the CPU core clock at runtime. > > > > This patch adds the support to change CPU frequency using the standard > > cpufreq interface. The ratio CORE to CCB can be 1:1(except MPC8536), 3:2, > > 2:1, 5:2, 3:1, 7:2 and 4:1. > > > > Two CPU cores on P1022 must not in the low power state during the frequency > > transition. The driver uses a atomic counter to meet the requirement. > > > > The jog mode frequency transition process on the MPC8536 is similar to > > the deep sleep process. The driver need save the CPU state and restore > > it after CPU warm reset. > > > > Note: > > * The I/O peripherals such as PCIe and eTSEC may lose packets during > > the jog mode frequency transition. > > * The driver doesn't support MPC8536 Rev 1.0 due to a JOG erratum. > > Subsequent revisions of MPC8536 have corrected the erratum. > > > > Signed-off-by: Dave Liu <daveliu@xxxxxxxxxxxxx> > > Signed-off-by: Li Yang <leoli@xxxxxxxxxxxxx> > > Signed-off-by: Jerry Huang <Chang-Ming.Huang@xxxxxxxxxxxxx> > > Signed-off-by: Zhao Chenhui <chenhui.zhao@xxxxxxxxxxxxx> > > CC: Scott Wood <scottwood@xxxxxxxxxxxxx> > > Well, I'd like someone from the PowerPC camp to comment on this before I take it. > > Thanks, > Rafael > OK. Thanks. -Chenhui -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
