| Message ID | 20201104103657.18007-3-s.nawrocki@samsung.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v8,1/7] dt-bindings: devfreq: Add documentation for the interconnect properties | expand |
On Wed, Nov 04, 2020 at 11:36:52AM +0100, Sylwester Nawrocki wrote: > This patch adds a generic interconnect driver for Exynos SoCs in order > to provide interconnect functionality for each "samsung,exynos-bus" > compatible device. > > The SoC topology is a graph (or more specifically, a tree) and its > edges are described by specifying in the 'interconnects' property > the interconnect consumer path for each interconnect provider DT node. > > Each bus is now an interconnect provider and an interconnect node as > well (cf. Documentation/interconnect/interconnect.rst), i.e. every bus > registers itself as a node. Node IDs are not hard coded but rather > assigned dynamically at runtime. This approach allows for using this > driver with various Exynos SoCs. > > Frequencies requested via the interconnect API for a given node are > propagated to devfreq using dev_pm_qos_update_request(). Please note > that it is not an error when CONFIG_INTERCONNECT is 'n', in which > case all interconnect API functions are no-op. > > The samsung,data-clk-ratio DT property is used to specify the ratio > of the interconect bandwidth to the minimum data clock frequency > for each bus. > > Due to unspecified relative probing order, -EPROBE_DEFER may be > propagated to ensure that the parent is probed before its children. > > Signed-off-by: Artur Świgoń <a.swigon@samsung.com> > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > --- > Changes for v8: > - renamed drivers/interconnect/exynos to drivers/interconnect/samsung, > - added missing driver sync_state callback assignment. > > Changes for v7: > - adjusted to the DT property changes: "interconnects" instead > of "samsung,interconnect-parent", "samsung,data-clk-ratio" > instead of "bus-width", > - adaptation to of_icc_get_from_provider() function changes > in v5.10-rc1. > > Changes for v6: > - corrected of_node dereferencing in exynos_icc_get_parent() > function, > - corrected initialization of icc_node->name so as to avoid > direct of_node->name dereferencing, > - added parsing of bus-width DT property. > > Changes for v5: > - adjust to renamed exynos,interconnect-parent-node property, > - use automatically generated platform device id as the interconect > node id instead of a now unavailable devfreq->id field, > - add icc_ prefix to some variables to make the code more self-commenting, > - use icc_nodes_remove() instead of icc_node_del() + icc_node_destroy(), > - adjust to exynos,interconnect-parent-node property rename to > samsung,interconnect-parent, > - converted to a separate platform driver in drivers/interconnect. > --- > drivers/interconnect/Kconfig | 1 + > drivers/interconnect/Makefile | 1 + > drivers/interconnect/samsung/Kconfig | 13 +++ > drivers/interconnect/samsung/Makefile | 4 + > drivers/interconnect/samsung/exynos.c | 199 ++++++++++++++++++++++++++++++++++ > 5 files changed, 218 insertions(+) > create mode 100644 drivers/interconnect/samsung/Kconfig > create mode 100644 drivers/interconnect/samsung/Makefile > create mode 100644 drivers/interconnect/samsung/exynos.c > > diff --git a/drivers/interconnect/Kconfig b/drivers/interconnect/Kconfig > index 5b7204e..d637a89 100644 > --- a/drivers/interconnect/Kconfig > +++ b/drivers/interconnect/Kconfig > @@ -13,5 +13,6 @@ if INTERCONNECT > > source "drivers/interconnect/imx/Kconfig" > source "drivers/interconnect/qcom/Kconfig" > +source "drivers/interconnect/samsung/Kconfig" > > endif > diff --git a/drivers/interconnect/Makefile b/drivers/interconnect/Makefile > index d203520..c2f9e9d 100644 > --- a/drivers/interconnect/Makefile > +++ b/drivers/interconnect/Makefile > @@ -6,3 +6,4 @@ icc-core-objs := core.o bulk.o > obj-$(CONFIG_INTERCONNECT) += icc-core.o > obj-$(CONFIG_INTERCONNECT_IMX) += imx/ > obj-$(CONFIG_INTERCONNECT_QCOM) += qcom/ > +obj-$(CONFIG_INTERCONNECT_SAMSUNG) += samsung/ > \ No newline at end of file This needs a fix. > diff --git a/drivers/interconnect/samsung/Kconfig b/drivers/interconnect/samsung/Kconfig > new file mode 100644 > index 0000000..508ed64 > --- /dev/null > +++ b/drivers/interconnect/samsung/Kconfig > @@ -0,0 +1,13 @@ > +# SPDX-License-Identifier: GPL-2.0-only > +config INTERCONNECT_SAMSUNG > + bool "Samsung interconnect drivers" "Samsung SoC interconnect drivers" > + depends on ARCH_EXYNOS || COMPILE_TEST Don't the depend on INTERCONNECT? > + help > + Interconnect drivers for Samsung SoCs. > + > + One line break > +config INTERCONNECT_EXYNOS > + tristate "Exynos generic interconnect driver" > + depends on INTERCONNECT_SAMSUNG How about: default y if ARCH_EXYNOS > + help > + Generic interconnect driver for Exynos SoCs. > diff --git a/drivers/interconnect/samsung/Makefile b/drivers/interconnect/samsung/Makefile > new file mode 100644 > index 0000000..e19d1df > --- /dev/null > +++ b/drivers/interconnect/samsung/Makefile > @@ -0,0 +1,4 @@ > +# SPDX-License-Identifier: GPL-2.0 > +exynos-interconnect-objs := exynos.o What is this line for? Best regards, Krzysztof > + > +obj-$(CONFIG_INTERCONNECT_EXYNOS) += exynos-interconnect.o > diff --git a/drivers/interconnect/samsung/exynos.c b/drivers/interconnect/samsung/exynos.c > new file mode 100644 > index 0000000..6559d8c
On Wed, Nov 04, 2020 at 02:22:37PM +0100, Sylwester Nawrocki wrote: > On 04.11.2020 13:37, Krzysztof Kozlowski wrote: > > On Wed, Nov 04, 2020 at 11:36:52AM +0100, Sylwester Nawrocki wrote: > > >> diff --git a/drivers/interconnect/Makefile b/drivers/interconnect/Makefile > >> index d203520..c2f9e9d 100644 > >> --- a/drivers/interconnect/Makefile > >> +++ b/drivers/interconnect/Makefile > >> @@ -6,3 +6,4 @@ icc-core-objs := core.o bulk.o > >> obj-$(CONFIG_INTERCONNECT) += icc-core.o > >> obj-$(CONFIG_INTERCONNECT_IMX) += imx/ > >> obj-$(CONFIG_INTERCONNECT_QCOM) += qcom/ > >> +obj-$(CONFIG_INTERCONNECT_SAMSUNG) += samsung/ > >> \ No newline at end of file > > > > This needs a fix. > > Corrected, thanks for pointing out. > > >> diff --git a/drivers/interconnect/samsung/Kconfig b/drivers/interconnect/samsung/Kconfig > >> new file mode 100644 > >> index 0000000..508ed64 > >> --- /dev/null > >> +++ b/drivers/interconnect/samsung/Kconfig > >> @@ -0,0 +1,13 @@ > >> +# SPDX-License-Identifier: GPL-2.0-only > >> +config INTERCONNECT_SAMSUNG > >> + bool "Samsung interconnect drivers" > > > > "Samsung SoC interconnect drivers" > > Changed. > > >> + depends on ARCH_EXYNOS || COMPILE_TEST > > > > Don't the depend on INTERCONNECT? > > This file gets included only if INTERCONNECT is enabled, see > higher level Kconfig file. I missed the include part, looks good. > > >> + help > >> + Interconnect drivers for Samsung SoCs. > >> + > >> + > > > > One line break > > Fixed. > > >> +config INTERCONNECT_EXYNOS > >> + tristate "Exynos generic interconnect driver" > >> + depends on INTERCONNECT_SAMSUNG > > > > How about: > > default y if ARCH_EXYNOS > > OK, added. > > >> + help > >> + Generic interconnect driver for Exynos SoCs. > >> diff --git a/drivers/interconnect/samsung/Makefile b/drivers/interconnect/samsung/Makefile > >> new file mode 100644 > >> index 0000000..e19d1df > >> --- /dev/null > >> +++ b/drivers/interconnect/samsung/Makefile > >> @@ -0,0 +1,4 @@ > >> +# SPDX-License-Identifier: GPL-2.0 > >> +exynos-interconnect-objs := exynos.o > > > > What is this line for? > > That allows to change the module name, so it's exynos-interconnect.ko > rather than just exynos.c. It's done similarly for other SoCs in > the subsystem. Thanks, makes sense. Best regards, Krzysztof
diff --git a/drivers/interconnect/Kconfig b/drivers/interconnect/Kconfig index 5b7204e..d637a89 100644 --- a/drivers/interconnect/Kconfig +++ b/drivers/interconnect/Kconfig @@ -13,5 +13,6 @@ if INTERCONNECT source "drivers/interconnect/imx/Kconfig" source "drivers/interconnect/qcom/Kconfig" +source "drivers/interconnect/samsung/Kconfig" endif diff --git a/drivers/interconnect/Makefile b/drivers/interconnect/Makefile index d203520..c2f9e9d 100644 --- a/drivers/interconnect/Makefile +++ b/drivers/interconnect/Makefile @@ -6,3 +6,4 @@ icc-core-objs := core.o bulk.o obj-$(CONFIG_INTERCONNECT) += icc-core.o obj-$(CONFIG_INTERCONNECT_IMX) += imx/ obj-$(CONFIG_INTERCONNECT_QCOM) += qcom/ +obj-$(CONFIG_INTERCONNECT_SAMSUNG) += samsung/ \ No newline at end of file diff --git a/drivers/interconnect/samsung/Kconfig b/drivers/interconnect/samsung/Kconfig new file mode 100644 index 0000000..508ed64 --- /dev/null +++ b/drivers/interconnect/samsung/Kconfig @@ -0,0 +1,13 @@ +# SPDX-License-Identifier: GPL-2.0-only +config INTERCONNECT_SAMSUNG + bool "Samsung interconnect drivers" + depends on ARCH_EXYNOS || COMPILE_TEST + help + Interconnect drivers for Samsung SoCs. + + +config INTERCONNECT_EXYNOS + tristate "Exynos generic interconnect driver" + depends on INTERCONNECT_SAMSUNG + help + Generic interconnect driver for Exynos SoCs. diff --git a/drivers/interconnect/samsung/Makefile b/drivers/interconnect/samsung/Makefile new file mode 100644 index 0000000..e19d1df --- /dev/null +++ b/drivers/interconnect/samsung/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 +exynos-interconnect-objs := exynos.o + +obj-$(CONFIG_INTERCONNECT_EXYNOS) += exynos-interconnect.o diff --git a/drivers/interconnect/samsung/exynos.c b/drivers/interconnect/samsung/exynos.c new file mode 100644 index 0000000..6559d8c --- /dev/null +++ b/drivers/interconnect/samsung/exynos.c @@ -0,0 +1,199 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Exynos generic interconnect provider driver + * + * Copyright (c) 2020 Samsung Electronics Co., Ltd. + * + * Authors: Artur Świgoń <a.swigon@samsung.com> + * Sylwester Nawrocki <s.nawrocki@samsung.com> + */ +#include <linux/device.h> +#include <linux/interconnect-provider.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_qos.h> +#include <linux/slab.h> + +#define EXYNOS_ICC_DEFAULT_BUS_CLK_RATIO 8 + +struct exynos_icc_priv { + struct device *dev; + + /* One interconnect node per provider */ + struct icc_provider provider; + struct icc_node *node; + + struct dev_pm_qos_request qos_req; + u32 bus_clk_ratio; +}; + +static struct icc_node *exynos_icc_get_parent(struct device_node *np) +{ + struct of_phandle_args args; + struct icc_node_data *icc_node_data; + struct icc_node *icc_node; + int num, ret; + + num = of_count_phandle_with_args(np, "interconnects", + "#interconnect-cells"); + if (num < 1) + return NULL; /* parent nodes are optional */ + + /* Get the interconnect target node */ + ret = of_parse_phandle_with_args(np, "interconnects", + "#interconnect-cells", 0, &args); + if (ret < 0) + return ERR_PTR(ret); + + icc_node_data = of_icc_get_from_provider(&args); + of_node_put(args.np); + + if (IS_ERR(icc_node_data)) + return ERR_CAST(icc_node_data); + + icc_node = icc_node_data->node; + kfree(icc_node_data); + + return icc_node; +} + +static int exynos_generic_icc_set(struct icc_node *src, struct icc_node *dst) +{ + struct exynos_icc_priv *src_priv = src->data, *dst_priv = dst->data; + s32 src_freq = max(src->avg_bw, src->peak_bw) / src_priv->bus_clk_ratio; + s32 dst_freq = max(dst->avg_bw, dst->peak_bw) / dst_priv->bus_clk_ratio; + int ret; + + ret = dev_pm_qos_update_request(&src_priv->qos_req, src_freq); + if (ret < 0) { + dev_err(src_priv->dev, "failed to update PM QoS of %s (src)\n", + src->name); + return ret; + } + + ret = dev_pm_qos_update_request(&dst_priv->qos_req, dst_freq); + if (ret < 0) { + dev_err(dst_priv->dev, "failed to update PM QoS of %s (dst)\n", + dst->name); + return ret; + } + + return 0; +} + +static struct icc_node *exynos_generic_icc_xlate(struct of_phandle_args *spec, + void *data) +{ + struct exynos_icc_priv *priv = data; + + if (spec->np != priv->dev->parent->of_node) + return ERR_PTR(-EINVAL); + + return priv->node; +} + +static int exynos_generic_icc_remove(struct platform_device *pdev) +{ + struct exynos_icc_priv *priv = platform_get_drvdata(pdev); + struct icc_node *parent_node, *node = priv->node; + + parent_node = exynos_icc_get_parent(priv->dev->parent->of_node); + if (parent_node && !IS_ERR(parent_node)) + icc_link_destroy(node, parent_node); + + icc_nodes_remove(&priv->provider); + icc_provider_del(&priv->provider); + + return 0; +} + +static int exynos_generic_icc_probe(struct platform_device *pdev) +{ + struct device *bus_dev = pdev->dev.parent; + struct exynos_icc_priv *priv; + struct icc_provider *provider; + struct icc_node *icc_node, *icc_parent_node; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = &pdev->dev; + platform_set_drvdata(pdev, priv); + + provider = &priv->provider; + + provider->set = exynos_generic_icc_set; + provider->aggregate = icc_std_aggregate; + provider->xlate = exynos_generic_icc_xlate; + provider->dev = bus_dev; + provider->inter_set = true; + provider->data = priv; + + ret = icc_provider_add(provider); + if (ret < 0) + return ret; + + icc_node = icc_node_create(pdev->id); + if (IS_ERR(icc_node)) { + ret = PTR_ERR(icc_node); + goto err_prov_del; + } + + priv->node = icc_node; + icc_node->name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn", + bus_dev->of_node); + if (of_property_read_u32(bus_dev->of_node, "samsung,data-clock-ratio", + &priv->bus_clk_ratio)) + priv->bus_clk_ratio = EXYNOS_ICC_DEFAULT_BUS_CLK_RATIO; + + /* + * Register a PM QoS request for the parent (devfreq) device. + */ + ret = dev_pm_qos_add_request(bus_dev, &priv->qos_req, + DEV_PM_QOS_MIN_FREQUENCY, 0); + if (ret < 0) + goto err_node_del; + + icc_node->data = priv; + icc_node_add(icc_node, provider); + + icc_parent_node = exynos_icc_get_parent(bus_dev->of_node); + if (IS_ERR(icc_parent_node)) { + ret = PTR_ERR(icc_parent_node); + goto err_pmqos_del; + } + if (icc_parent_node) { + ret = icc_link_create(icc_node, icc_parent_node->id); + if (ret < 0) + goto err_pmqos_del; + } + + return 0; + +err_pmqos_del: + dev_pm_qos_remove_request(&priv->qos_req); +err_node_del: + icc_nodes_remove(provider); +err_prov_del: + icc_provider_del(provider); + return ret; +} + +static struct platform_driver exynos_generic_icc_driver = { + .driver = { + .name = "exynos-generic-icc", + .sync_state = icc_sync_state, + }, + .probe = exynos_generic_icc_probe, + .remove = exynos_generic_icc_remove, +}; +module_platform_driver(exynos_generic_icc_driver); + +MODULE_DESCRIPTION("Exynos generic interconnect driver"); +MODULE_AUTHOR("Artur Świgoń <a.swigon@samsung.com>"); +MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:exynos-generic-icc");