[RFC PATCH] drivers: soc: xilinx: Add ZynqMP PM driver
Jolly Shah
jolly.shah at xilinx.com
Mon Jan 8 14:10:44 PST 2018
Add ZynqMP PM driver. PM driver provides power management
support for ZynqMP.
Signed-off-by: Jolly Shah <jollys at xilinx.com>
Signed-off-by: Rajan Vaja <rajanv at xilinx.com>
---
.../bindings/soc/xilinx/xlnx,zynqmp-pm.txt | 15 ++
drivers/soc/Kconfig | 1 +
drivers/soc/Makefile | 1 +
drivers/soc/xilinx/Kconfig | 4 +
drivers/soc/xilinx/Makefile | 4 +
drivers/soc/xilinx/zynqmp/Kconfig | 15 ++
drivers/soc/xilinx/zynqmp/Makefile | 1 +
drivers/soc/xilinx/zynqmp/pm.c | 265 +++++++++++++++++++++
8 files changed, 306 insertions(+)
create mode 100644 Documentation/devicetree/bindings/soc/xilinx/xlnx,zynqmp-pm.txt
create mode 100644 drivers/soc/xilinx/Kconfig
create mode 100644 drivers/soc/xilinx/Makefile
create mode 100644 drivers/soc/xilinx/zynqmp/Kconfig
create mode 100644 drivers/soc/xilinx/zynqmp/Makefile
create mode 100644 drivers/soc/xilinx/zynqmp/pm.c
diff --git a/Documentation/devicetree/bindings/soc/xilinx/xlnx,zynqmp-pm.txt b/Documentation/devicetree/bindings/soc/xilinx/xlnx,zynqmp-pm.txt
new file mode 100644
index 0000000..9cfb40d
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/xilinx/xlnx,zynqmp-pm.txt
@@ -0,0 +1,15 @@
+Xilinx Zynq MPSoC Power Management Device Tree Bindings
+
+The zynqmp-pm node describes the power management configurations.
+
+Required properties:
+ - compatible : Must contain: "xlnx,zynqmp-pm"
+ - interrupt-parent : Interrupt controller the interrupt is routed through
+ - interrupts : Interrupt specifier
+
+Examples:
+ zynqmp-firmware {
+ compatible = "xlnx,zynqmp-pm";
+ interrupt-parent = <&gic>;
+ interrupts = <0 35 4>;
+ };
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index fc9e980..c07b4a8 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -16,6 +16,7 @@ source "drivers/soc/tegra/Kconfig"
source "drivers/soc/ti/Kconfig"
source "drivers/soc/ux500/Kconfig"
source "drivers/soc/versatile/Kconfig"
+source "drivers/soc/xilinx/Kconfig"
source "drivers/soc/zte/Kconfig"
endmenu
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index deecb16..abb019a 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
obj-$(CONFIG_SOC_SAMSUNG) += samsung/
obj-$(CONFIG_ARCH_SUNXI) += sunxi/
obj-$(CONFIG_ARCH_TEGRA) += tegra/
+obj-$(CONFIG_ARCH_ZYNQMP) += xilinx/
obj-$(CONFIG_SOC_TI) += ti/
obj-$(CONFIG_ARCH_U8500) += ux500/
obj-$(CONFIG_PLAT_VERSATILE) += versatile/
diff --git a/drivers/soc/xilinx/Kconfig b/drivers/soc/xilinx/Kconfig
new file mode 100644
index 0000000..190add7
--- /dev/null
+++ b/drivers/soc/xilinx/Kconfig
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Kconfig for Xilinx SoCs
+
+source "drivers/soc/xilinx/zynqmp/Kconfig"
diff --git a/drivers/soc/xilinx/Makefile b/drivers/soc/xilinx/Makefile
new file mode 100644
index 0000000..bc9d560
--- /dev/null
+++ b/drivers/soc/xilinx/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Makefile for Xilinx SoCs
+
+obj-$(CONFIG_ARCH_ZYNQMP) += zynqmp/
diff --git a/drivers/soc/xilinx/zynqmp/Kconfig b/drivers/soc/xilinx/zynqmp/Kconfig
new file mode 100644
index 0000000..d3c784d
--- /dev/null
+++ b/drivers/soc/xilinx/zynqmp/Kconfig
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Kconfig for Xilinx zynqmp SoC
+#
+menu "Zynq MPSoC SoC Drivers"
+ depends on ARCH_ZYNQMP
+
+
+config ZYNQMP_PM
+ bool "Enable Xilinx Zynq MPSoC Power Management"
+ depends on PM
+ help
+ Say yes to enable power management support for
+ ZyqnMP SoC. In doubt, say N.
+
+endmenu
diff --git a/drivers/soc/xilinx/zynqmp/Makefile b/drivers/soc/xilinx/zynqmp/Makefile
new file mode 100644
index 0000000..98034f7
--- /dev/null
+++ b/drivers/soc/xilinx/zynqmp/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_ZYNQMP_PM) += pm.o
diff --git a/drivers/soc/xilinx/zynqmp/pm.c b/drivers/soc/xilinx/zynqmp/pm.c
new file mode 100644
index 0000000..7178fb5
--- /dev/null
+++ b/drivers/soc/xilinx/zynqmp/pm.c
@@ -0,0 +1,265 @@
+/*
+ * Xilinx Zynq MPSoC Power Management
+ *
+ * Copyright (C) 2014-2017 Xilinx, Inc.
+ *
+ * Davorin Mista <davorin.mista at aggios.com>
+ * Jolly Shah <jollys at xilinx.com>
+ * Rajan Vaja <rajanv at xilinx.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <linux/compiler.h>
+#include <linux/arm-smccc.h>
+#include <linux/of.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/uaccess.h>
+#include <linux/platform_device.h>
+#include <linux/debugfs.h>
+#include <linux/reboot.h>
+#include <linux/suspend.h>
+#include <linux/firmware/xilinx/zynqmp/firmware.h>
+
+#define DRIVER_NAME "zynqmp_pm"
+
+/**
+ * struct zynqmp_pm_work_struct - Wrapper for struct work_struct
+ * @callback_work: Work structure
+ * @args: Callback arguments
+ */
+struct zynqmp_pm_work_struct {
+ struct work_struct callback_work;
+ u32 args[CB_ARG_CNT];
+};
+
+static struct zynqmp_pm_work_struct *zynqmp_pm_init_suspend_work;
+
+enum pm_suspend_mode {
+ PM_SUSPEND_MODE_STD,
+ PM_SUSPEND_MODE_POWER_OFF,
+};
+
+#define PM_SUSPEND_MODE_FIRST PM_SUSPEND_MODE_STD
+
+static const char *const suspend_modes[] = {
+ [PM_SUSPEND_MODE_STD] = "standard",
+ [PM_SUSPEND_MODE_POWER_OFF] = "power-off",
+};
+
+static enum pm_suspend_mode suspend_mode = PM_SUSPEND_MODE_STD;
+
+enum pm_api_cb_id {
+ PM_INIT_SUSPEND_CB = 30,
+ PM_ACKNOWLEDGE_CB,
+ PM_NOTIFY_CB,
+};
+
+static irqreturn_t zynqmp_pm_isr(int irq, void *data)
+{
+ u32 payload[CB_PAYLOAD_SIZE];
+ const struct zynqmp_eemi_ops *eemi_ops = get_eemi_ops();
+
+ if (!eemi_ops || !eemi_ops->get_callback_data)
+ return IRQ_NONE;
+
+ eemi_ops->get_callback_data(payload);
+
+ if (!payload[0])
+ return IRQ_NONE;
+
+ /* First element is callback API ID, others are callback arguments */
+ if (payload[0] == PM_INIT_SUSPEND_CB) {
+ if (work_pending(&zynqmp_pm_init_suspend_work->callback_work))
+ goto done;
+
+ /* Copy callback arguments into work's structure */
+ memcpy(zynqmp_pm_init_suspend_work->args, &payload[1],
+ sizeof(zynqmp_pm_init_suspend_work->args));
+
+ queue_work(system_unbound_wq,
+ &zynqmp_pm_init_suspend_work->callback_work);
+ }
+
+done:
+ return IRQ_HANDLED;
+}
+
+static const struct of_device_id pm_of_match[] = {
+ { .compatible = "xlnx,zynqmp-pm", },
+ { /* end of table */ },
+};
+
+MODULE_DEVICE_TABLE(of, pm_of_match);
+
+/**
+ * zynqmp_pm_init_suspend_work_fn - Initialize suspend
+ * @work: Pointer to work_struct
+ *
+ * Bottom-half of PM callback IRQ handler.
+ */
+static void zynqmp_pm_init_suspend_work_fn(struct work_struct *work)
+{
+ struct zynqmp_pm_work_struct *pm_work =
+ container_of(work, struct zynqmp_pm_work_struct, callback_work);
+
+ if (pm_work->args[0] == ZYNQMP_PM_SUSPEND_REASON_SYSTEM_SHUTDOWN) {
+ orderly_poweroff(true);
+ } else if (pm_work->args[0] ==
+ ZYNQMP_PM_SUSPEND_REASON_POWER_UNIT_REQUEST) {
+ pm_suspend(PM_SUSPEND_MEM);
+ } else {
+ pr_err("%s Unsupported InitSuspendCb reason code %d.\n"
+ , __func__, pm_work->args[0]);
+ }
+}
+
+static ssize_t suspend_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ char *s = buf;
+ int md;
+
+ for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
+ if (suspend_modes[md]) {
+ if (md == suspend_mode)
+ s += sprintf(s, "[%s] ", suspend_modes[md]);
+ else
+ s += sprintf(s, "%s ", suspend_modes[md]);
+ }
+
+ /* Convert last space to newline */
+ if (s != buf)
+ *(s - 1) = '\n';
+ return (s - buf);
+}
+
+static ssize_t suspend_mode_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int md, ret = -EINVAL;
+ const struct zynqmp_eemi_ops *eemi_ops = get_eemi_ops();
+
+ if (!eemi_ops || !eemi_ops->set_suspend_mode)
+ return ret;
+
+ for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
+ if (suspend_modes[md] &&
+ sysfs_streq(suspend_modes[md], buf)) {
+ ret = 0;
+ break;
+ }
+
+ if (!ret && md != suspend_mode) {
+ ret = eemi_ops->set_suspend_mode(md);
+ if (likely(!ret))
+ suspend_mode = md;
+ }
+
+ return ret ? ret : count;
+}
+
+static DEVICE_ATTR_RW(suspend_mode);
+
+/**
+ * zynqmp_pm_sysfs_init - Initialize PM driver sysfs interface
+ * @dev: Pointer to device structure
+ *
+ * Return: 0 on success, negative error code otherwise
+ */
+static int zynqmp_pm_sysfs_init(struct device *dev)
+{
+ return sysfs_create_file(&dev->kobj, &dev_attr_suspend_mode.attr);
+}
+
+/**
+ * zynqmp_pm_probe - Probe existence of the PMU Firmware
+ * and initialize debugfs interface
+ *
+ * @pdev: Pointer to the platform_device structure
+ *
+ * Return: Returns 0 on success
+ * Negative error code otherwise
+ */
+static int zynqmp_pm_probe(struct platform_device *pdev)
+{
+ int ret, irq;
+ u32 pm_api_version;
+ const struct zynqmp_eemi_ops *eemi_ops = get_eemi_ops();
+
+ if (!eemi_ops || !eemi_ops->get_api_version)
+ return -ENXIO;
+
+ eemi_ops->get_api_version(&pm_api_version);
+
+ /* Check PM API version number */
+ if (pm_api_version != ZYNQMP_PM_VERSION)
+ return -ENODEV;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0)
+ return -ENXIO;
+
+ ret = request_irq(irq, zynqmp_pm_isr, IRQF_SHARED, DRIVER_NAME, pdev);
+ if (ret) {
+ dev_err(&pdev->dev, "request_irq '%d' failed with %d\n",
+ irq, ret);
+ return ret;
+ }
+
+ zynqmp_pm_init_suspend_work =
+ devm_kzalloc(&pdev->dev, sizeof(struct zynqmp_pm_work_struct),
+ GFP_KERNEL);
+ if (!zynqmp_pm_init_suspend_work) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work,
+ zynqmp_pm_init_suspend_work_fn);
+
+ ret = zynqmp_pm_sysfs_init(&pdev->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to initialize sysfs interface\n");
+ goto error;
+ }
+
+ dev_info(&pdev->dev, "Power management API v%d.%d\n",
+ ZYNQMP_PM_VERSION_MAJOR, ZYNQMP_PM_VERSION_MINOR);
+
+ return 0;
+
+error:
+ free_irq(irq, 0);
+ return ret;
+}
+
+static struct platform_driver zynqmp_pm_platform_driver = {
+ .probe = zynqmp_pm_probe,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = pm_of_match,
+ },
+};
+builtin_platform_driver(zynqmp_pm_platform_driver);
+
+/**
+ * zynqmp_pm_init - Notify PM firmware that initialization is completed
+ *
+ * Return: Status returned from the PM firmware
+ */
+static int __init zynqmp_pm_init(void)
+{
+ const struct zynqmp_eemi_ops *eemi_ops = get_eemi_ops();
+
+ if (!eemi_ops || !eemi_ops->init_finalize)
+ return -ENXIO;
+
+ return eemi_ops->init_finalize();
+}
+
+late_initcall_sync(zynqmp_pm_init);
--
2.7.4
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