diff options
Diffstat (limited to 'docs/pmu_support.md')
| -rw-r--r-- | docs/pmu_support.md | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/docs/pmu_support.md b/docs/pmu_support.md index d79b515..1db36fc 100644 --- a/docs/pmu_support.md +++ b/docs/pmu_support.md @@ -1,7 +1,7 @@ OpenSBI SBI PMU extension support ================================== SBI PMU extension supports allow supervisor software to configure/start/stop -any performance counter at anytime. Thus, an user can leverage full +any performance counter at anytime. Thus, a user can leverage full capability of performance analysis tools such as perf if SBI PMU extension is enabled. The OpenSBI implementation makes the following assumptions about the hardware platform. @@ -25,7 +25,7 @@ SBI PMU Device Tree Bindings ---------------------------- Platforms may choose to describe PMU event selector and event to counter mapping -values via device tree. The following sections describes the PMU DT node +values via device tree. The following sections describe the PMU DT node bindings in details. * **compatible** (Mandatory) - The compatible string of SBI PMU device tree node. @@ -42,7 +42,7 @@ This property shouldn't encode any raw hardware event. * **riscv,event-to-mhpmcounters**(Optional) - It represents a MANY-to-MANY mapping between a range of events and all the MHPMCOUNTERx in a bitmap format that can be used to monitor these range of events. The information is encoded in -a table format where each row represent a certain range of events and +a table format where each row represents a certain range of events and corresponding counters. The first column represents starting of the pmu event id and 2nd column represents the end of the pmu event id. The third column represent a bitmap of all the MHPMCOUNTERx. This property is mandatory if @@ -53,10 +53,10 @@ shouldn't encode any raw event. or MANY-to-MANY mapping between the raw event(s) and all the MHPMCOUNTERx in a bitmap format that can be used to monitor that raw event. The encoding of the raw events are platform specific. The information is encoded in a table format -where each row represent the specific raw event(s). The first column is a 64bit +where each row represents the specific raw event(s). The first column is a 64bit match value where the invariant bits of range of events are set. The second column is a 64 bit mask that will have all the variant bits of the range of -events cleared. Every other bits should be set in the mask. +events cleared. All other bits should be set in the mask. The third column is a 32bit value to represent bitmap of all MHPMCOUNTERx that can monitor these set of event(s). If a platform directly encodes each raw PMU event as a unique ID, the value of |