From 16375747c127e39dc986225bb138670e0469826d Mon Sep 17 00:00:00 2001 From: Atish Patra Date: Mon, 27 Nov 2023 01:30:28 -0800 Subject: [PATCH] Clarify the PMU snapshot functionality The PMU snapshot function is an optional function and the SBI implementation may not implement it. It may be useful to distinguish that from other error to allow further clarification to the user. Signed-off-by: Atish Patra --- src/ext-pmu.adoc | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/src/ext-pmu.adoc b/src/ext-pmu.adoc index dbfd23f..0673403 100644 --- a/src/ext-pmu.adoc +++ b/src/ext-pmu.adoc @@ -529,6 +529,9 @@ then the PMU snapshot shared memory is cleared and disabled. The `flags` parameter is reserved for future use and must be zero. +This is an optional function and the SBI implementation may choose not to +implement it. + [#table_snapshot_shmem_layout] .SBI PMU Snapshot shared memory layout [cols="5,2,2,5", width=90%, align="center", options="header"] @@ -567,6 +570,8 @@ The possible error codes returned in `sbiret.error` are shown in |=== | Error code | Description | SBI_SUCCESS | Shared memory was set or cleared successfully. +| SBI_ERR_NOT_SUPPORTED | The SBI PMU snapshot functionality is not available + in the SBI implementation. | SBI_ERR_INVALID_PARAM | The `flags` parameter is not zero or the `shmem_phys_lo` parameter is not 4096 bytes aligned. | SBI_ERR_INVALID_ADDRESS | The shared memory pointed to by the `shmem_phys_lo`