On Fri, May 29, 2020 at 06:31:56PM +0200, 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 specified using the 'samsung,interconnect-parent' in the DT. Due to unspecified relative probing order, -EPROBE_DEFER may be propagated to ensure that the parent is probed before its children.
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 hardcoded 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.
Signed-off-by: Artur Świgoń a.swigon@samsung.com Signed-off-by: Sylwester Nawrocki s.nawrocki@samsung.com
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/exynos/Kconfig | 6 ++ drivers/interconnect/exynos/Makefile | 4 + drivers/interconnect/exynos/exynos.c | 185 +++++++++++++++++++++++++++++++++++ 5 files changed, 197 insertions(+) create mode 100644 drivers/interconnect/exynos/Kconfig create mode 100644 drivers/interconnect/exynos/Makefile create mode 100644 drivers/interconnect/exynos/exynos.c
diff --git a/drivers/interconnect/Kconfig b/drivers/interconnect/Kconfig index 5b7204e..eca6eda 100644 --- a/drivers/interconnect/Kconfig +++ b/drivers/interconnect/Kconfig @@ -11,6 +11,7 @@ menuconfig INTERCONNECT
if INTERCONNECT
+source "drivers/interconnect/exynos/Kconfig" source "drivers/interconnect/imx/Kconfig" source "drivers/interconnect/qcom/Kconfig"
diff --git a/drivers/interconnect/Makefile b/drivers/interconnect/Makefile index 4825c28..2ba1de6 100644 --- a/drivers/interconnect/Makefile +++ b/drivers/interconnect/Makefile @@ -4,5 +4,6 @@ CFLAGS_core.o := -I$(src) icc-core-objs := core.o
obj-$(CONFIG_INTERCONNECT) += icc-core.o +obj-$(CONFIG_INTERCONNECT_EXYNOS) += exynos/ obj-$(CONFIG_INTERCONNECT_IMX) += imx/ obj-$(CONFIG_INTERCONNECT_QCOM) += qcom/ diff --git a/drivers/interconnect/exynos/Kconfig b/drivers/interconnect/exynos/Kconfig new file mode 100644 index 0000000..e51e52e --- /dev/null +++ b/drivers/interconnect/exynos/Kconfig @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0-only +config INTERCONNECT_EXYNOS
- tristate "Exynos generic interconnect driver"
- depends on ARCH_EXYNOS || COMPILE_TEST
- help
Generic interconnect driver for Exynos SoCs.diff --git a/drivers/interconnect/exynos/Makefile b/drivers/interconnect/exynos/Makefile new file mode 100644 index 0000000..e19d1df --- /dev/null +++ b/drivers/interconnect/exynos/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 +exynos-interconnect-objs := exynos.o
+obj-$(CONFIG_INTERCONNECT_EXYNOS) += exynos-interconnect.o diff --git a/drivers/interconnect/exynos/exynos.c b/drivers/interconnect/exynos/exynos.c new file mode 100644 index 0000000..8278194 --- /dev/null +++ b/drivers/interconnect/exynos/exynos.c @@ -0,0 +1,185 @@ +// 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>
+#define kbps_to_khz(x) ((x) / 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;
+};
+static struct icc_node *exynos_icc_get_parent(struct device_node *np) +{
- struct of_phandle_args args;
- int num, ret;
- num = of_count_phandle_with_args(np, "samsung,interconnect-parent",
"#interconnect-cells");- if (num != 1)
return NULL; /* parent nodes are optional */- ret = of_parse_phandle_with_args(np, "samsung,interconnect-parent",
"#interconnect-cells", 0, &args);- if (ret < 0)
return ERR_PTR(ret);- of_node_put(args.np);
- return of_icc_get_from_provider(&args);
I think of_node_put() should happen after of_icc_get_from_provider().
Best regards, Krzysztof