Re: [PATCH v4 1/2] perf: starfive: Add StarLink PMU support

[Rob Herring]

On Thu, Nov 16, 2023 at 10:24 AM Ji Sheng Teoh
<jisheng.teoh@xxxxxxxxxxxxxxxx> wrote:
>
> This patch adds support for StarFive's StarLink PMU (Performance
> Monitor Unit). StarLink PMU integrates one or more CPU cores with
> a shared L3 memory system. The PMU supports overflow interrupt,
> up to 16 programmable 64bit event counters, and an independent
> 64bit cycle counter. StarLink PMU is accessed via MMIO.
>
> Example Perf stat output:
> [root@user]# perf stat -a -e /starfive_starlink_pmu/cycles/ \
>         -e /starfive_starlink_pmu/read_miss/ \
>         -e /starfive_starlink_pmu/read_hit/ \
>         -e /starfive_starlink_pmu/release_request/  \
>         -e /starfive_starlink_pmu/write_hit/ \
>         -e /starfive_starlink_pmu/write_miss/ \
>         -e /starfive_starlink_pmu/write_request/ \
>         -e /starfive_starlink_pmu/writeback/ \
>         -e /starfive_starlink_pmu/read_request/ \
>         -- openssl speed rsa2048
> Doing 2048 bits private rsa's for 10s: 5 2048 bits private RSA's in
> 2.84s
> Doing 2048 bits public rsa's for 10s: 169 2048 bits public RSA's in
> 2.42s
> version: 3.0.11
> built on: Tue Sep 19 13:02:31 2023 UTC
> options: bn(64,64)
> CPUINFO: N/A
>                   sign    verify    sign/s verify/s
> rsa 2048 bits 0.568000s 0.014320s      1.8     69.8
> /////////
>  Performance counter stats for 'system wide':
>
>          649991998      starfive_starlink_pmu/cycles/
>            1009690      starfive_starlink_pmu/read_miss/
>            1079750      starfive_starlink_pmu/read_hit/
>            2089405      starfive_starlink_pmu/release_request/
>                129      starfive_starlink_pmu/write_hit/
>                 70      starfive_starlink_pmu/write_miss/
>                194      starfive_starlink_pmu/write_request/
>             150080      starfive_starlink_pmu/writeback/
>            2089423      starfive_starlink_pmu/read_request/
>
>       27.062755678 seconds time elapsed
>
> Signed-off-by: Ji Sheng Teoh <jisheng.teoh@xxxxxxxxxxxxxxxx>
> ---
>  drivers/perf/Kconfig                 |   9 +
>  drivers/perf/Makefile                |   1 +
>  drivers/perf/starfive_starlink_pmu.c | 654 +++++++++++++++++++++++++++
>  include/linux/cpuhotplug.h           |   1 +
>  4 files changed, 665 insertions(+)
>  create mode 100644 drivers/perf/starfive_starlink_pmu.c
>
> diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
> index 273d67ecf6d2..41278742ef88 100644
> --- a/drivers/perf/Kconfig
> +++ b/drivers/perf/Kconfig
> @@ -86,6 +86,15 @@ config RISCV_PMU_SBI
>           full perf feature support i.e. counter overflow, privilege mode
>           filtering, counter configuration.
>
> +config STARFIVE_STARLINK_PMU
> +       depends on ARCH_STARFIVE
> +       bool "StarFive StarLink PMU"
> +       help
> +          Provide support for StarLink Performance Monitor Unit.
> +          StarLink Performance Monitor Unit integrates one or more cores with
> +          an L3 memory system. The L3 cache events are added into perf event
> +          subsystem, allowing monitoring of various L3 cache perf events.
> +
>  config ARM_PMU_ACPI
>         depends on ARM_PMU && ACPI
>         def_bool y
> diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
> index 16b3ec4db916..e2153aee1e04 100644
> --- a/drivers/perf/Makefile
> +++ b/drivers/perf/Makefile
> @@ -15,6 +15,7 @@ obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o
>  obj-$(CONFIG_RISCV_PMU) += riscv_pmu.o
>  obj-$(CONFIG_RISCV_PMU_LEGACY) += riscv_pmu_legacy.o
>  obj-$(CONFIG_RISCV_PMU_SBI) += riscv_pmu_sbi.o
> +obj-$(CONFIG_STARFIVE_STARLINK_PMU) += starfive_starlink_pmu.o
>  obj-$(CONFIG_THUNDERX2_PMU) += thunderx2_pmu.o
>  obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o
>  obj-$(CONFIG_ARM_SPE_PMU) += arm_spe_pmu.o
> diff --git a/drivers/perf/starfive_starlink_pmu.c b/drivers/perf/starfive_starlink_pmu.c
> new file mode 100644
> index 000000000000..272896ab1ade
> --- /dev/null
> +++ b/drivers/perf/starfive_starlink_pmu.c
> @@ -0,0 +1,654 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * StarFive's StarLink PMU driver
> + *
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + *
> + * Author: Ji Sheng Teoh <jisheng.teoh@xxxxxxxxxxxxxxxx>
> + *
> + */
> +
> +#define STARLINK_PMU_PDEV_NAME "starfive_starlink_pmu"
> +#define pr_fmt(fmt)    STARLINK_PMU_PDEV_NAME ": " fmt
> +
> +#include <linux/bitmap.h>
> +#include <linux/cpu_pm.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>

You probably don't need this header and the implicit includes it makes
are dropped now in linux-next. Please check what you actually need and
make them explicit.

Rob