The DTPM framework does support now the hierarchy description.

The platform specific code can call the hierarchy creation function
with an array of struct dtpm_node pointing to their parents.

This patch provides a description of the big and Little CPUs and the
GPU and tie them together under a virtual package name. Only sdm845 is
described.

The description could be extended in the future with the memory
controller with devfreq if it has the energy information.

Signed-off-by: Daniel Lezcano <redacted>
---
  drivers/soc/qcom/Kconfig  |  9 ++++++
  drivers/soc/qcom/Makefile |  1 +
  drivers/soc/qcom/dtpm.c   | 65 +++++++++++++++++++++++++++++++++++++++
  3 files changed, 75 insertions(+)
  create mode 100644 drivers/soc/qcom/dtpm.c

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index e718b8735444..f21c1df2f2f9 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig

@@ -228,4 +228,13 @@ config QCOM_APR
  	  application processor and QDSP6. APR is
  	  used by audio driver to configure QDSP6
  	  ASM, ADM and AFE modules.
+
+config QCOM_DTPM
+	tristate "Qualcomm DTPM hierarchy"

+	depends on DTPM
+	help
+	 Describe the hierarchy for the Dynamic Thermal Power
+	 Management tree on this platform. That will create all the
+	 power capping capable devices.
+
  endmenu

diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 70d5de69fd7b..cf38496c3f61 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile

@@ -28,3 +28,4 @@ obj-$(CONFIG_QCOM_LLCC) += llcc-qcom.o
  obj-$(CONFIG_QCOM_RPMHPD) += rpmhpd.o
  obj-$(CONFIG_QCOM_RPMPD) += rpmpd.o
  obj-$(CONFIG_QCOM_KRYO_L2_ACCESSORS) +=	kryo-l2-accessors.o
+obj-$(CONFIG_QCOM_DTPM) += dtpm.o

diff --git a/drivers/soc/qcom/dtpm.c b/drivers/soc/qcom/dtpm.c
new file mode 100644
index 000000000000..c15283f59494
--- /dev/null
+++ b/drivers/soc/qcom/dtpm.c

@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2021 Linaro Limited
+ *
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * DTPM hierarchy description
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/dtpm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+static struct dtpm_node __initdata sdm845_hierarchy[] = {
+	[0]{ .name = "sdm845" },
+	[1]{ .name = "package",
+	     .parent = &sdm845_hierarchy[0] },
+	[2]{ .name = "/cpus/cpu@0",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[3]{ .name = "/cpus/cpu@100",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[4]{ .name = "/cpus/cpu@200",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[5]{ .name = "/cpus/cpu@300",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[6]{ .name = "/cpus/cpu@400",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[7]{ .name = "/cpus/cpu@500",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[8]{ .name = "/cpus/cpu@600",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[9]{ .name = "/cpus/cpu@700",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[10]{ .name = "/soc@0/gpu@5000000",
+	     .type = DTPM_NODE_DT,
+	     .parent = &sdm845_hierarchy[1] },
+	[11]{ },
+};
+
+static struct of_device_id __initdata sdm845_dtpm_match_table[] = {
+        { .compatible = "qcom,sdm845", .data = sdm845_hierarchy },
+        {},
+};
+
+static int __init sdm845_dtpm_init(void)
+{
+	return dtpm_create_hierarchy(sdm845_dtpm_match_table);
+}
+late_initcall(sdm845_dtpm_init);
+
+MODULE_DESCRIPTION("Qualcomm DTPM driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:dtpm");
+MODULE_AUTHOR("Daniel Lezcano <daniel.lezcano@kernel.org");
+