5 files changed, 348 insertions, 0 deletions

diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
new file mode 100644
index 000000000000..bcf554602561
--- /dev/null
+++ b/drivers/soc/microchip/Kconfig
@@ -0,0 +1,23 @@
+config POLARFIRE_SOC_SYS_CTRL
+	tristate "Microchip PolarFire SoC (MPFS) system controller support"
+	depends on POLARFIRE_SOC_MAILBOX
+	depends on MTD
+	help
+	  This driver adds support for the PolarFire SoC (MPFS) system controller.
+
+	  To compile this driver as a module, choose M here. the
+	  module will be called mpfs_system_controller.
+
+	  If unsure, say N.
+
+config POLARFIRE_SOC_SYSCONS
+	bool "PolarFire SoC (MPFS) syscon drivers"
+	default y
+	depends on ARCH_MICROCHIP
+	select MFD_CORE
+	help
+	  These drivers add support for the syscons on PolarFire SoC (MPFS).
+	  Without these drivers core parts of the kernel such as clocks
+	  and resets will not function correctly.
+
+	  If unsure, and on a PolarFire SoC, say y.
diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
new file mode 100644
index 000000000000..1a3a1594b089
--- /dev/null
+++ b/drivers/soc/microchip/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_POLARFIRE_SOC_SYS_CTRL)	+= mpfs-sys-controller.o
+obj-$(CONFIG_POLARFIRE_SOC_SYSCONS)	+= mpfs-control-scb.o mpfs-mss-top-sysreg.o
diff --git a/drivers/soc/microchip/mpfs-control-scb.c b/drivers/soc/microchip/mpfs-control-scb.c
new file mode 100644
index 000000000000..f0b84b1f49cb
--- /dev/null
+++ b/drivers/soc/microchip/mpfs-control-scb.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/array_size.h>
+#include <linux/of.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+
+static const struct mfd_cell mpfs_control_scb_devs[] = {
+	MFD_CELL_NAME("mpfs-tvs"),
+};
+
+static int mpfs_control_scb_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+
+	return mfd_add_devices(dev, PLATFORM_DEVID_NONE, mpfs_control_scb_devs,
+			       ARRAY_SIZE(mpfs_control_scb_devs), NULL, 0, NULL);
+}
+
+static const struct of_device_id mpfs_control_scb_of_match[] = {
+	{ .compatible = "microchip,mpfs-control-scb", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpfs_control_scb_of_match);
+
+static struct platform_driver mpfs_control_scb_driver = {
+	.driver = {
+		.name = "mpfs-control-scb",
+		.of_match_table = mpfs_control_scb_of_match,
+	},
+	.probe = mpfs_control_scb_probe,
+};
+module_platform_driver(mpfs_control_scb_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_DESCRIPTION("PolarFire SoC control scb driver");
diff --git a/drivers/soc/microchip/mpfs-mss-top-sysreg.c b/drivers/soc/microchip/mpfs-mss-top-sysreg.c
new file mode 100644
index 000000000000..b2244e44ff0f
--- /dev/null
+++ b/drivers/soc/microchip/mpfs-mss-top-sysreg.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/array_size.h>
+#include <linux/of.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+static const struct mfd_cell mpfs_mss_top_sysreg_devs[] = {
+	MFD_CELL_NAME("mpfs-reset"),
+};
+
+static int mpfs_mss_top_sysreg_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	ret = mfd_add_devices(dev, PLATFORM_DEVID_NONE, mpfs_mss_top_sysreg_devs,
+			      ARRAY_SIZE(mpfs_mss_top_sysreg_devs) , NULL, 0, NULL);
+	if (ret)
+		return ret;
+
+	return devm_of_platform_populate(dev);
+}
+
+static const struct of_device_id mpfs_mss_top_sysreg_of_match[] = {
+	{ .compatible = "microchip,mpfs-mss-top-sysreg", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpfs_mss_top_sysreg_of_match);
+
+static struct platform_driver mpfs_mss_top_sysreg_driver = {
+	.driver = {
+		.name = "mpfs-mss-top-sysreg",
+		.of_match_table = mpfs_mss_top_sysreg_of_match,
+	},
+	.probe = mpfs_mss_top_sysreg_probe,
+};
+module_platform_driver(mpfs_mss_top_sysreg_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_DESCRIPTION("PolarFire SoC mss top sysreg driver");
diff --git a/drivers/soc/microchip/mpfs-sys-controller.c b/drivers/soc/microchip/mpfs-sys-controller.c
new file mode 100644
index 000000000000..30bc45d17d34
--- /dev/null
+++ b/drivers/soc/microchip/mpfs-sys-controller.c
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip PolarFire SoC (MPFS) system controller driver
+ *
+ * Copyright (c) 2020-2021 Microchip Corporation. All rights reserved.
+ *
+ * Author: Conor Dooley <conor.dooley@microchip.com>
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/kref.h>
+#include <linux/module.h>
+#include <linux/jiffies.h>
+#include <linux/mtd/mtd.h>
+#include <linux/spi/spi.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/mailbox_client.h>
+#include <linux/platform_device.h>
+#include <soc/microchip/mpfs.h>
+
+/*
+ * This timeout must be long, as some services (example: image authentication)
+ * take significant time to complete
+ */
+#define MPFS_SYS_CTRL_TIMEOUT_MS 30000
+
+static DEFINE_MUTEX(transaction_lock);
+
+struct mpfs_sys_controller {
+	struct mbox_client client;
+	struct mbox_chan *chan;
+	struct completion c;
+	struct mtd_info *flash;
+	struct kref consumers;
+};
+
+int mpfs_blocking_transaction(struct mpfs_sys_controller *sys_controller, struct mpfs_mss_msg *msg)
+{
+	unsigned long timeout = msecs_to_jiffies(MPFS_SYS_CTRL_TIMEOUT_MS);
+	int ret;
+
+	ret = mutex_lock_interruptible(&transaction_lock);
+	if (ret)
+		return ret;
+
+	reinit_completion(&sys_controller->c);
+
+	ret = mbox_send_message(sys_controller->chan, msg);
+	if (ret < 0) {
+		dev_warn(sys_controller->client.dev, "MPFS sys controller service timeout\n");
+		goto out;
+	}
+
+	/*
+	 * Unfortunately, the system controller will only deliver an interrupt
+	 * if a service succeeds. mbox_send_message() will block until the busy
+	 * flag is gone. If the busy flag is gone but no interrupt has arrived
+	 * to trigger the rx callback then the service can be deemed to have
+	 * failed.
+	 * The caller can then interrogate msg::response::resp_status to
+	 * determine the cause of the failure.
+	 * mbox_send_message() returns positive integers in the success path, so
+	 * ret needs to be cleared if we do get an interrupt.
+	 */
+	if (!wait_for_completion_timeout(&sys_controller->c, timeout)) {
+		ret = -EBADMSG;
+		dev_warn(sys_controller->client.dev,
+			 "MPFS sys controller service failed with status: %d\n",
+			 msg->response->resp_status);
+	} else {
+		ret = 0;
+	}
+
+out:
+	mutex_unlock(&transaction_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL(mpfs_blocking_transaction);
+
+static void mpfs_sys_controller_rx_callback(struct mbox_client *client, void *msg)
+{
+	struct mpfs_sys_controller *sys_controller =
+		container_of(client, struct mpfs_sys_controller, client);
+
+	complete(&sys_controller->c);
+}
+
+static void mpfs_sys_controller_delete(struct kref *kref)
+{
+	struct mpfs_sys_controller *sys_controller =
+		container_of(kref, struct mpfs_sys_controller, consumers);
+
+	mbox_free_channel(sys_controller->chan);
+	kfree(sys_controller);
+}
+
+static void mpfs_sys_controller_put(void *data)
+{
+	struct mpfs_sys_controller *sys_controller = data;
+
+	kref_put(&sys_controller->consumers, mpfs_sys_controller_delete);
+}
+
+struct mtd_info *mpfs_sys_controller_get_flash(struct mpfs_sys_controller *mpfs_client)
+{
+	return mpfs_client->flash;
+}
+EXPORT_SYMBOL(mpfs_sys_controller_get_flash);
+
+static struct platform_device subdevs[] = {
+	{
+		.name		= "mpfs-rng",
+		.id		= -1,
+	},
+	{
+		.name		= "mpfs-generic-service",
+		.id		= -1,
+	},
+	{
+		.name		= "mpfs-auto-update",
+		.id		= -1,
+	},
+};
+
+static int mpfs_sys_controller_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mpfs_sys_controller *sys_controller;
+	struct device_node *np;
+	int i, ret;
+
+	sys_controller = kzalloc(sizeof(*sys_controller), GFP_KERNEL);
+	if (!sys_controller)
+		return -ENOMEM;
+
+	np = of_parse_phandle(dev->of_node, "microchip,bitstream-flash", 0);
+	if (!np)
+		goto no_flash;
+
+	sys_controller->flash = of_get_mtd_device_by_node(np);
+	of_node_put(np);
+	if (IS_ERR(sys_controller->flash))
+		return dev_err_probe(dev, PTR_ERR(sys_controller->flash), "Failed to get flash\n");
+
+no_flash:
+	sys_controller->client.dev = dev;
+	sys_controller->client.rx_callback = mpfs_sys_controller_rx_callback;
+	sys_controller->client.tx_block = 1U;
+	sys_controller->client.tx_tout = msecs_to_jiffies(MPFS_SYS_CTRL_TIMEOUT_MS);
+
+	sys_controller->chan = mbox_request_channel(&sys_controller->client, 0);
+	if (IS_ERR(sys_controller->chan)) {
+		ret = dev_err_probe(dev, PTR_ERR(sys_controller->chan),
+				    "Failed to get mbox channel\n");
+		kfree(sys_controller);
+		return ret;
+	}
+
+	init_completion(&sys_controller->c);
+	kref_init(&sys_controller->consumers);
+
+	platform_set_drvdata(pdev, sys_controller);
+
+
+	for (i = 0; i < ARRAY_SIZE(subdevs); i++) {
+		subdevs[i].dev.parent = dev;
+		if (platform_device_register(&subdevs[i]))
+			dev_warn(dev, "Error registering sub device %s\n", subdevs[i].name);
+	}
+
+	dev_info(&pdev->dev, "Registered MPFS system controller\n");
+
+	return 0;
+}
+
+static void mpfs_sys_controller_remove(struct platform_device *pdev)
+{
+	struct mpfs_sys_controller *sys_controller = platform_get_drvdata(pdev);
+
+	mpfs_sys_controller_put(sys_controller);
+}
+
+static const struct of_device_id mpfs_sys_controller_of_match[] = {
+	{.compatible = "microchip,mpfs-sys-controller", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpfs_sys_controller_of_match);
+
+struct mpfs_sys_controller *mpfs_sys_controller_get(struct device *dev)
+{
+	const struct of_device_id *match;
+	struct mpfs_sys_controller *sys_controller;
+	int ret;
+
+	if (!dev->parent)
+		goto err_no_device;
+
+	match = of_match_node(mpfs_sys_controller_of_match,  dev->parent->of_node);
+	of_node_put(dev->parent->of_node);
+	if (!match)
+		goto err_no_device;
+
+	sys_controller = dev_get_drvdata(dev->parent);
+	if (!sys_controller)
+		goto err_bad_device;
+
+	if (!kref_get_unless_zero(&sys_controller->consumers))
+		goto err_bad_device;
+
+	ret = devm_add_action_or_reset(dev, mpfs_sys_controller_put, sys_controller);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return sys_controller;
+
+err_no_device:
+	dev_dbg(dev, "Parent device was not an MPFS system controller\n");
+	return ERR_PTR(-ENODEV);
+
+err_bad_device:
+	dev_dbg(dev, "MPFS system controller found but could not register as a sub device\n");
+	return ERR_PTR(-EPROBE_DEFER);
+}
+EXPORT_SYMBOL(mpfs_sys_controller_get);
+
+static struct platform_driver mpfs_sys_controller_driver = {
+	.driver = {
+		.name = "mpfs-sys-controller",
+		.of_match_table = mpfs_sys_controller_of_match,
+	},
+	.probe = mpfs_sys_controller_probe,
+	.remove = mpfs_sys_controller_remove,
+};
+module_platform_driver(mpfs_sys_controller_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_DESCRIPTION("MPFS system controller driver");