Hi Mark, On Tue, Apr 5, 2016 at 12:21 PM, Mark Rutland <mark.rutland@xxxxxxx> wrote: > On Tue, Apr 05, 2016 at 11:50:10AM -0700, Tai Tri Nguyen wrote: >> On Mon, Apr 4, 2016 at 4:33 PM, Mark Rutland <mark.rutland@xxxxxxx> wrote: >> > On Mon, Apr 04, 2016 at 04:42:11PM -0700, Tai Tri Nguyen wrote: >> >> On Fri, Apr 1, 2016 at 5:18 AM, Mark Rutland <mark.rutland@xxxxxxx> wrote: >> >> >> + hwc->config = config; >> >> >> + if (config1) >> >> >> + hwc->extra_reg.config = config1; >> >> >> + else >> >> >> + /* Enable all Agents */ >> >> >> + hwc->extra_reg.config = 0xFFFFFFFFFFFFFFFFULL; >> >> > >> >> > I'm not sure I follow what's going on here. >> >> > >> >> > It would be good to document precisely what this means. >> >> >> >> These are X-Gene PMU specific for monitoring performance of a specific >> >> data path. >> >> X-Gene PMUs have 2 registers capable of masking the Agents from which >> >> the request come from. If the bit with the bit number corresponding to >> >> the AgentID >> >> is set, the event will be counted only if it is caused by a request >> >> from that agent. >> >> Each PMU has different set of Agents. By default, the event will be counted for >> >> all agent requests. >> >> >> >> I'll have it commented better for next revision of the patch. >> > >> > It might be worth having something under Documentation/ for this, similarly to >> > what we do for CCN in Documentation/arm/CCN.txt. >> > >> > How is the user expected to determine agent IDs? Is there a listing somewhere? >> > Does this change between reivisions? This may be worth documenting. >> > >> >> Each of the SoC PMU has an agent ID list in our product User Manual >> documentation. >> An user is expected to refer to the list to determine the agent ID. >> The agent ID list >> per each PMU is different. Also we may change or add more agents to the list for >> next generations of APM X-Gene. I think it would be too much to document it in >> the Documentation/ folder. > > Given that the IDs are so variable, you can simply defer to user manuals in the > documentation. However, there should definitely be documentation describing the > format of the config and config1 fields. > > Thanks, > Mark. Yes, I agree and will add it. Thanks, -- Tai -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
