2023-09-19 13:28:32

by Ulf Hansson

[permalink] [raw]
Subject: [PATCH v4 13/13] pmdomain: arm: Add the SCMI performance domain

To enable support for performance scaling (DVFS) for generic devices with
the SCMI performance protocol, let's add an SCMI performance domain. This
is being modelled as a genpd provider, with support for performance scaling
through genpd's ->set_performance_state() callback.

Note that, this adds the initial support that allows consumer drivers for
attached devices, to vote for a new performance state via calling the
dev_pm_genpd_set_performance_state(). However, this should be avoided as
it's in most cases preferred to use the OPP library to vote for a new OPP
instead. The support using the OPP library isn't part of this change, but
needs to be implemented from subsequent changes.

Signed-off-by: Ulf Hansson <[email protected]>
---

Sudeep, Cristian,

I decided to just send this a single patch, rather than a new version of the
complete series. If you prefer a new version of the series, please let me know.

Kind regards
Uffe

Changes in v4:
- Rebased on v6.6-rc2 to be able to put the files in the new pmdomain
subsystem (was genpd in v6.6-rc1).

Changes in v3:
- Move files to drivers/genpd/arm/ and update MAINTAINERS.
- Updated the commit msg header.
- Prevent setting performance level 0.
- Initialize the genpd as always-on.
- Note, the corresponding Kconfigs should be placed in the genpd dir
too, but that's better suited on top or through a later-version.

---
MAINTAINERS | 1 +
drivers/firmware/arm_scmi/Kconfig | 12 ++
drivers/pmdomain/Makefile | 1 +
drivers/pmdomain/arm/Makefile | 3 +
drivers/pmdomain/arm/scmi_perf_domain.c | 150 ++++++++++++++++++++++++
5 files changed, 167 insertions(+)
create mode 100644 drivers/pmdomain/arm/Makefile
create mode 100644 drivers/pmdomain/arm/scmi_perf_domain.c

diff --git a/MAINTAINERS b/MAINTAINERS
index bf0f54c24f81..aa8c58b16416 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -20902,6 +20902,7 @@ F: drivers/clk/clk-sc[mp]i.c
F: drivers/cpufreq/sc[mp]i-cpufreq.c
F: drivers/firmware/arm_scmi/
F: drivers/firmware/arm_scpi.c
+F: drivers/pmdomain/arm/
F: drivers/powercap/arm_scmi_powercap.c
F: drivers/regulator/scmi-regulator.c
F: drivers/reset/reset-scmi.c
diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index ea0f5083ac47..706d1264d038 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -181,6 +181,18 @@ config ARM_SCMI_POWER_DOMAIN
will be called scmi_pm_domain. Note this may needed early in boot
before rootfs may be available.

+config ARM_SCMI_PERF_DOMAIN
+ tristate "SCMI performance domain driver"
+ depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
+ default y
+ select PM_GENERIC_DOMAINS if PM
+ help
+ This enables support for the SCMI performance domains which can be
+ enabled or disabled via the SCP firmware.
+
+ This driver can also be built as a module. If so, the module will be
+ called scmi_perf_domain.
+
config ARM_SCMI_POWER_CONTROL
tristate "SCMI system power control driver"
depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
diff --git a/drivers/pmdomain/Makefile b/drivers/pmdomain/Makefile
index 666753676e5c..f0326b27b30b 100644
--- a/drivers/pmdomain/Makefile
+++ b/drivers/pmdomain/Makefile
@@ -2,6 +2,7 @@
obj-y += actions/
obj-y += amlogic/
obj-y += apple/
+obj-y += arm/
obj-y += bcm/
obj-y += imx/
obj-y += mediatek/
diff --git a/drivers/pmdomain/arm/Makefile b/drivers/pmdomain/arm/Makefile
new file mode 100644
index 000000000000..7128db96deac
--- /dev/null
+++ b/drivers/pmdomain/arm/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_ARM_SCMI_PERF_DOMAIN) += scmi_perf_domain.o
diff --git a/drivers/pmdomain/arm/scmi_perf_domain.c b/drivers/pmdomain/arm/scmi_perf_domain.c
new file mode 100644
index 000000000000..aa100270500f
--- /dev/null
+++ b/drivers/pmdomain/arm/scmi_perf_domain.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SCMI performance domain support.
+ *
+ * Copyright (C) 2023 Linaro Ltd.
+ */
+
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pm_domain.h>
+#include <linux/scmi_protocol.h>
+#include <linux/slab.h>
+
+struct scmi_perf_domain {
+ struct generic_pm_domain genpd;
+ const struct scmi_perf_proto_ops *perf_ops;
+ const struct scmi_protocol_handle *ph;
+ const struct scmi_perf_domain_info *info;
+ u32 domain_id;
+};
+
+#define to_scmi_pd(pd) container_of(pd, struct scmi_perf_domain, genpd)
+
+static int
+scmi_pd_set_perf_state(struct generic_pm_domain *genpd, unsigned int state)
+{
+ struct scmi_perf_domain *pd = to_scmi_pd(genpd);
+ int ret;
+
+ if (!pd->info->set_perf)
+ return 0;
+
+ if (!state)
+ return -EINVAL;
+
+ ret = pd->perf_ops->level_set(pd->ph, pd->domain_id, state, true);
+ if (ret)
+ dev_warn(&genpd->dev, "Failed with %d when trying to set %d perf level",
+ ret, state);
+
+ return ret;
+}
+
+static int scmi_perf_domain_probe(struct scmi_device *sdev)
+{
+ struct device *dev = &sdev->dev;
+ const struct scmi_handle *handle = sdev->handle;
+ const struct scmi_perf_proto_ops *perf_ops;
+ struct scmi_protocol_handle *ph;
+ struct scmi_perf_domain *scmi_pd;
+ struct genpd_onecell_data *scmi_pd_data;
+ struct generic_pm_domain **domains;
+ int num_domains, i, ret = 0;
+
+ if (!handle)
+ return -ENODEV;
+
+ /* The OF node must specify us as a power-domain provider. */
+ if (!of_find_property(dev->of_node, "#power-domain-cells", NULL))
+ return 0;
+
+ perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph);
+ if (IS_ERR(perf_ops))
+ return PTR_ERR(perf_ops);
+
+ num_domains = perf_ops->num_domains_get(ph);
+ if (num_domains < 0) {
+ dev_warn(dev, "Failed with %d when getting num perf domains\n",
+ num_domains);
+ return num_domains;
+ } else if (!num_domains) {
+ return 0;
+ }
+
+ scmi_pd = devm_kcalloc(dev, num_domains, sizeof(*scmi_pd), GFP_KERNEL);
+ if (!scmi_pd)
+ return -ENOMEM;
+
+ scmi_pd_data = devm_kzalloc(dev, sizeof(*scmi_pd_data), GFP_KERNEL);
+ if (!scmi_pd_data)
+ return -ENOMEM;
+
+ domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL);
+ if (!domains)
+ return -ENOMEM;
+
+ for (i = 0; i < num_domains; i++, scmi_pd++) {
+ scmi_pd->info = perf_ops->info_get(ph, i);
+
+ scmi_pd->domain_id = i;
+ scmi_pd->perf_ops = perf_ops;
+ scmi_pd->ph = ph;
+ scmi_pd->genpd.name = scmi_pd->info->name;
+ scmi_pd->genpd.flags = GENPD_FLAG_ALWAYS_ON |
+ GENPD_FLAG_OPP_TABLE_FW;
+ scmi_pd->genpd.set_performance_state = scmi_pd_set_perf_state;
+
+ ret = pm_genpd_init(&scmi_pd->genpd, NULL, false);
+ if (ret)
+ goto err;
+
+ domains[i] = &scmi_pd->genpd;
+ }
+
+ scmi_pd_data->domains = domains;
+ scmi_pd_data->num_domains = num_domains;
+
+ ret = of_genpd_add_provider_onecell(dev->of_node, scmi_pd_data);
+ if (ret)
+ goto err;
+
+ dev_set_drvdata(dev, scmi_pd_data);
+ dev_info(dev, "Initialized %d performance domains", num_domains);
+ return 0;
+err:
+ for (i--; i >= 0; i--)
+ pm_genpd_remove(domains[i]);
+ return ret;
+}
+
+static void scmi_perf_domain_remove(struct scmi_device *sdev)
+{
+ struct device *dev = &sdev->dev;
+ struct genpd_onecell_data *scmi_pd_data = dev_get_drvdata(dev);
+ int i;
+
+ of_genpd_del_provider(dev->of_node);
+
+ for (i = 0; i < scmi_pd_data->num_domains; i++)
+ pm_genpd_remove(scmi_pd_data->domains[i]);
+}
+
+static const struct scmi_device_id scmi_id_table[] = {
+ { SCMI_PROTOCOL_PERF, "perf" },
+ { },
+};
+MODULE_DEVICE_TABLE(scmi, scmi_id_table);
+
+static struct scmi_driver scmi_perf_domain_driver = {
+ .name = "scmi-perf-domain",
+ .probe = scmi_perf_domain_probe,
+ .remove = scmi_perf_domain_remove,
+ .id_table = scmi_id_table,
+};
+module_scmi_driver(scmi_perf_domain_driver);
+
+MODULE_AUTHOR("Ulf Hansson <[email protected]>");
+MODULE_DESCRIPTION("ARM SCMI perf domain driver");
+MODULE_LICENSE("GPL v2");
--
2.34.1


2023-09-21 22:49:53

by Sudeep Holla

[permalink] [raw]
Subject: [PATCH] firmware: arm_scmi: Move power-domain driver to the pmdomain dir

To simplify with maintenance let's move the Arm SCMI power-domain driver
to the new pmdomain directory.

Cc: Ulf Hansson <[email protected]>
Cc: Cristian Marussi <[email protected]>
Signed-off-by: Sudeep Holla <[email protected]>
---

Hi Ulf,

If you are happy with this, please cck. I would like to take this along
with your scmi_perf_domain change as part of you series.

Regards,
Sudeep

drivers/firmware/arm_scmi/Makefile | 1 -
drivers/pmdomain/arm/Makefile | 1 +
drivers/{firmware/arm_scmi => pmdomain/arm}/scmi_pm_domain.c | 0
3 files changed, 1 insertion(+), 1 deletion(-)
rename drivers/{firmware/arm_scmi => pmdomain/arm}/scmi_pm_domain.c (100%)

diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index b31d78fa66cc..a7bc4796519c 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -16,7 +16,6 @@ scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o

-obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o
obj-$(CONFIG_ARM_SCMI_POWER_CONTROL) += scmi_power_control.o

ifeq ($(CONFIG_THUMB2_KERNEL)$(CONFIG_CC_IS_CLANG),yy)
diff --git a/drivers/pmdomain/arm/Makefile b/drivers/pmdomain/arm/Makefile
index 7128db96deac..cfcb1f6cdd90 100644
--- a/drivers/pmdomain/arm/Makefile
+++ b/drivers/pmdomain/arm/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only

obj-$(CONFIG_ARM_SCMI_PERF_DOMAIN) += scmi_perf_domain.o
+obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o
diff --git a/drivers/firmware/arm_scmi/scmi_pm_domain.c b/drivers/pmdomain/arm/scmi_pm_domain.c
similarity index 100%
rename from drivers/firmware/arm_scmi/scmi_pm_domain.c
rename to drivers/pmdomain/arm/scmi_pm_domain.c
--
2.42.0

2023-09-21 23:19:45

by Ulf Hansson

[permalink] [raw]
Subject: Re: [PATCH] firmware: arm_scmi: Move power-domain driver to the pmdomain dir

On Thu, 21 Sept 2023 at 13:33, Sudeep Holla <[email protected]> wrote:
>
> To simplify with maintenance let's move the Arm SCMI power-domain driver
> to the new pmdomain directory.
>
> Cc: Ulf Hansson <[email protected]>
> Cc: Cristian Marussi <[email protected]>
> Signed-off-by: Sudeep Holla <[email protected]>

Reviewed-by: Ulf Hansson <[email protected]>

Feel free to take it through your scmi tree!

Note that, we should move the Kconfig options too, but that requires
changes that I am carrying in my pmdomain tree. We can either wait
until the next cycle or you could send your pull-request to me this
time (instead of through arm-soc), then we can fix this as a late
minute change. The decision is yours.

Kind regards
Uffe

> ---
>
> Hi Ulf,
>
> If you are happy with this, please cck. I would like to take this along
> with your scmi_perf_domain change as part of you series.
>
> Regards,
> Sudeep
>
> drivers/firmware/arm_scmi/Makefile | 1 -
> drivers/pmdomain/arm/Makefile | 1 +
> drivers/{firmware/arm_scmi => pmdomain/arm}/scmi_pm_domain.c | 0
> 3 files changed, 1 insertion(+), 1 deletion(-)
> rename drivers/{firmware/arm_scmi => pmdomain/arm}/scmi_pm_domain.c (100%)
>
> diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
> index b31d78fa66cc..a7bc4796519c 100644
> --- a/drivers/firmware/arm_scmi/Makefile
> +++ b/drivers/firmware/arm_scmi/Makefile
> @@ -16,7 +16,6 @@ scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
> obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
> obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o
>
> -obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o
> obj-$(CONFIG_ARM_SCMI_POWER_CONTROL) += scmi_power_control.o
>
> ifeq ($(CONFIG_THUMB2_KERNEL)$(CONFIG_CC_IS_CLANG),yy)
> diff --git a/drivers/pmdomain/arm/Makefile b/drivers/pmdomain/arm/Makefile
> index 7128db96deac..cfcb1f6cdd90 100644
> --- a/drivers/pmdomain/arm/Makefile
> +++ b/drivers/pmdomain/arm/Makefile
> @@ -1,3 +1,4 @@
> # SPDX-License-Identifier: GPL-2.0-only
>
> obj-$(CONFIG_ARM_SCMI_PERF_DOMAIN) += scmi_perf_domain.o
> +obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o
> diff --git a/drivers/firmware/arm_scmi/scmi_pm_domain.c b/drivers/pmdomain/arm/scmi_pm_domain.c
> similarity index 100%
> rename from drivers/firmware/arm_scmi/scmi_pm_domain.c
> rename to drivers/pmdomain/arm/scmi_pm_domain.c
> --
> 2.42.0
>

2023-09-25 09:58:35

by Sudeep Holla

[permalink] [raw]
Subject: Re: [PATCH v4 13/13] pmdomain: arm: Add the SCMI performance domain

On Tue, 19 Sep 2023 14:16:05 +0200, Ulf Hansson wrote:
> To enable support for performance scaling (DVFS) for generic devices with
> the SCMI performance protocol, let's add an SCMI performance domain. This
> is being modelled as a genpd provider, with support for performance scaling
> through genpd's ->set_performance_state() callback.
>
> Note that, this adds the initial support that allows consumer drivers for
> attached devices, to vote for a new performance state via calling the
> dev_pm_genpd_set_performance_state(). However, this should be avoided as
> it's in most cases preferred to use the OPP library to vote for a new OPP
> instead. The support using the OPP library isn't part of this change, but
> needs to be implemented from subsequent changes.
>
> [...]

Applied to sudeep.holla/linux (for-next/scmi/updates), thanks!

[13/13] pmdomain: arm: Add the SCMI performance domain
https://git.kernel.org/sudeep.holla/c/2af23ceb8624
--
Regards,
Sudeep

2023-09-25 09:58:38

by Sudeep Holla

[permalink] [raw]
Subject: Re: [PATCH] firmware: arm_scmi: Move power-domain driver to the pmdomain dir

On Thu, Sep 21, 2023 at 12:33:28PM +0100, Sudeep Holla wrote:
> To simplify with maintenance let's move the Arm SCMI power-domain driver
> to the new pmdomain directory.
>
> Cc: Ulf Hansson <[email protected]>
> Cc: Cristian Marussi <[email protected]>
> Signed-off-by: Sudeep Holla <[email protected]>
> ---
>
> Hi Ulf,
>
> If you are happy with this, please cck. I would like to take this along
> with your scmi_perf_domain change as part of you series.
>
> Regards,
> Sudeep
>
> drivers/firmware/arm_scmi/Makefile | 1 -
> drivers/pmdomain/arm/Makefile | 1 +
> drivers/{firmware/arm_scmi => pmdomain/arm}/scmi_pm_domain.c | 0
> 3 files changed, 1 insertion(+), 1 deletion(-)
> rename drivers/{firmware/arm_scmi => pmdomain/arm}/scmi_pm_domain.c (100%)
>

Applied to sudeep.holla/linux (for-next/scmi/updates), thanks!

[1/1] firmware: arm_scmi: firmware: arm_scmi: Move power-domain driver to thepmdomain dir
https://git.kernel.org/sudeep.holla/c/af78e5c309c4

--
Regards,
Sudeep