1 files changed, 316 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_powernv.c b/drivers/char/ipmi/ipmi_powernv.c
new file mode 100644
index 0000000000..da22a8cbe6
--- /dev/null
+++ b/drivers/char/ipmi/ipmi_powernv.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * PowerNV OPAL IPMI driver
+ *
+ * Copyright 2014 IBM Corp.
+ */
+
+#define pr_fmt(fmt)        "ipmi-powernv: " fmt
+
+#include <linux/ipmi_smi.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/interrupt.h>
+
+#include <asm/opal.h>
+
+
+struct ipmi_smi_powernv {
+	u64			interface_id;
+	struct ipmi_smi		*intf;
+	unsigned int		irq;
+
+	/**
+	 * We assume that there can only be one outstanding request, so
+	 * keep the pending message in cur_msg. We protect this from concurrent
+	 * updates through send & recv calls, (and consequently opal_msg, which
+	 * is in-use when cur_msg is set) with msg_lock
+	 */
+	spinlock_t		msg_lock;
+	struct ipmi_smi_msg	*cur_msg;
+	struct opal_ipmi_msg	*opal_msg;
+};
+
+static int ipmi_powernv_start_processing(void *send_info, struct ipmi_smi *intf)
+{
+	struct ipmi_smi_powernv *smi = send_info;
+
+	smi->intf = intf;
+	return 0;
+}
+
+static void send_error_reply(struct ipmi_smi_powernv *smi,
+		struct ipmi_smi_msg *msg, u8 completion_code)
+{
+	msg->rsp[0] = msg->data[0] | 0x4;
+	msg->rsp[1] = msg->data[1];
+	msg->rsp[2] = completion_code;
+	msg->rsp_size = 3;
+	ipmi_smi_msg_received(smi->intf, msg);
+}
+
+static void ipmi_powernv_send(void *send_info, struct ipmi_smi_msg *msg)
+{
+	struct ipmi_smi_powernv *smi = send_info;
+	struct opal_ipmi_msg *opal_msg;
+	unsigned long flags;
+	int comp, rc;
+	size_t size;
+
+	/* ensure data_len will fit in the opal_ipmi_msg buffer... */
+	if (msg->data_size > IPMI_MAX_MSG_LENGTH) {
+		comp = IPMI_REQ_LEN_EXCEEDED_ERR;
+		goto err;
+	}
+
+	/* ... and that we at least have netfn and cmd bytes */
+	if (msg->data_size < 2) {
+		comp = IPMI_REQ_LEN_INVALID_ERR;
+		goto err;
+	}
+
+	spin_lock_irqsave(&smi->msg_lock, flags);
+
+	if (smi->cur_msg) {
+		comp = IPMI_NODE_BUSY_ERR;
+		goto err_unlock;
+	}
+
+	/* format our data for the OPAL API */
+	opal_msg = smi->opal_msg;
+	opal_msg->version = OPAL_IPMI_MSG_FORMAT_VERSION_1;
+	opal_msg->netfn = msg->data[0];
+	opal_msg->cmd = msg->data[1];
+	if (msg->data_size > 2)
+		memcpy(opal_msg->data, msg->data + 2, msg->data_size - 2);
+
+	/* data_size already includes the netfn and cmd bytes */
+	size = sizeof(*opal_msg) + msg->data_size - 2;
+
+	pr_devel("%s: opal_ipmi_send(0x%llx, %p, %ld)\n", __func__,
+			smi->interface_id, opal_msg, size);
+	rc = opal_ipmi_send(smi->interface_id, opal_msg, size);
+	pr_devel("%s:  -> %d\n", __func__, rc);
+
+	if (!rc) {
+		smi->cur_msg = msg;
+		spin_unlock_irqrestore(&smi->msg_lock, flags);
+		return;
+	}
+
+	comp = IPMI_ERR_UNSPECIFIED;
+err_unlock:
+	spin_unlock_irqrestore(&smi->msg_lock, flags);
+err:
+	send_error_reply(smi, msg, comp);
+}
+
+static int ipmi_powernv_recv(struct ipmi_smi_powernv *smi)
+{
+	struct opal_ipmi_msg *opal_msg;
+	struct ipmi_smi_msg *msg;
+	unsigned long flags;
+	uint64_t size;
+	int rc;
+
+	pr_devel("%s: opal_ipmi_recv(%llx, msg, sz)\n", __func__,
+			smi->interface_id);
+
+	spin_lock_irqsave(&smi->msg_lock, flags);
+
+	if (!smi->cur_msg) {
+		spin_unlock_irqrestore(&smi->msg_lock, flags);
+		pr_warn("no current message?\n");
+		return 0;
+	}
+
+	msg = smi->cur_msg;
+	opal_msg = smi->opal_msg;
+
+	size = cpu_to_be64(sizeof(*opal_msg) + IPMI_MAX_MSG_LENGTH);
+
+	rc = opal_ipmi_recv(smi->interface_id,
+			opal_msg,
+			&size);
+	size = be64_to_cpu(size);
+	pr_devel("%s:   -> %d (size %lld)\n", __func__,
+			rc, rc == 0 ? size : 0);
+	if (rc) {
+		/* If came via the poll, and response was not yet ready */
+		if (rc == OPAL_EMPTY) {
+			spin_unlock_irqrestore(&smi->msg_lock, flags);
+			return 0;
+		}
+
+		smi->cur_msg = NULL;
+		spin_unlock_irqrestore(&smi->msg_lock, flags);
+		send_error_reply(smi, msg, IPMI_ERR_UNSPECIFIED);
+		return 0;
+	}
+
+	if (size < sizeof(*opal_msg)) {
+		spin_unlock_irqrestore(&smi->msg_lock, flags);
+		pr_warn("unexpected IPMI message size %lld\n", size);
+		return 0;
+	}
+
+	if (opal_msg->version != OPAL_IPMI_MSG_FORMAT_VERSION_1) {
+		spin_unlock_irqrestore(&smi->msg_lock, flags);
+		pr_warn("unexpected IPMI message format (version %d)\n",
+				opal_msg->version);
+		return 0;
+	}
+
+	msg->rsp[0] = opal_msg->netfn;
+	msg->rsp[1] = opal_msg->cmd;
+	if (size > sizeof(*opal_msg))
+		memcpy(&msg->rsp[2], opal_msg->data, size - sizeof(*opal_msg));
+	msg->rsp_size = 2 + size - sizeof(*opal_msg);
+
+	smi->cur_msg = NULL;
+	spin_unlock_irqrestore(&smi->msg_lock, flags);
+	ipmi_smi_msg_received(smi->intf, msg);
+	return 0;
+}
+
+static void ipmi_powernv_request_events(void *send_info)
+{
+}
+
+static void ipmi_powernv_set_run_to_completion(void *send_info,
+		bool run_to_completion)
+{
+}
+
+static void ipmi_powernv_poll(void *send_info)
+{
+	struct ipmi_smi_powernv *smi = send_info;
+
+	ipmi_powernv_recv(smi);
+}
+
+static const struct ipmi_smi_handlers ipmi_powernv_smi_handlers = {
+	.owner			= THIS_MODULE,
+	.start_processing	= ipmi_powernv_start_processing,
+	.sender			= ipmi_powernv_send,
+	.request_events		= ipmi_powernv_request_events,
+	.set_run_to_completion	= ipmi_powernv_set_run_to_completion,
+	.poll			= ipmi_powernv_poll,
+};
+
+static irqreturn_t ipmi_opal_event(int irq, void *data)
+{
+	struct ipmi_smi_powernv *smi = data;
+
+	ipmi_powernv_recv(smi);
+	return IRQ_HANDLED;
+}
+
+static int ipmi_powernv_probe(struct platform_device *pdev)
+{
+	struct ipmi_smi_powernv *ipmi;
+	struct device *dev;
+	u32 prop;
+	int rc;
+
+	if (!pdev || !pdev->dev.of_node)
+		return -ENODEV;
+
+	dev = &pdev->dev;
+
+	ipmi = devm_kzalloc(dev, sizeof(*ipmi), GFP_KERNEL);
+	if (!ipmi)
+		return -ENOMEM;
+
+	spin_lock_init(&ipmi->msg_lock);
+
+	rc = of_property_read_u32(dev->of_node, "ibm,ipmi-interface-id",
+			&prop);
+	if (rc) {
+		dev_warn(dev, "No interface ID property\n");
+		goto err_free;
+	}
+	ipmi->interface_id = prop;
+
+	rc = of_property_read_u32(dev->of_node, "interrupts", &prop);
+	if (rc) {
+		dev_warn(dev, "No interrupts property\n");
+		goto err_free;
+	}
+
+	ipmi->irq = irq_of_parse_and_map(dev->of_node, 0);
+	if (!ipmi->irq) {
+		dev_info(dev, "Unable to map irq from device tree\n");
+		ipmi->irq = opal_event_request(prop);
+	}
+
+	rc = request_irq(ipmi->irq, ipmi_opal_event, IRQ_TYPE_LEVEL_HIGH,
+			 "opal-ipmi", ipmi);
+	if (rc) {
+		dev_warn(dev, "Unable to request irq\n");
+		goto err_dispose;
+	}
+
+	ipmi->opal_msg = devm_kmalloc(dev,
+			sizeof(*ipmi->opal_msg) + IPMI_MAX_MSG_LENGTH,
+			GFP_KERNEL);
+	if (!ipmi->opal_msg) {
+		rc = -ENOMEM;
+		goto err_unregister;
+	}
+
+	rc = ipmi_register_smi(&ipmi_powernv_smi_handlers, ipmi, dev, 0);
+	if (rc) {
+		dev_warn(dev, "IPMI SMI registration failed (%d)\n", rc);
+		goto err_free_msg;
+	}
+
+	dev_set_drvdata(dev, ipmi);
+	return 0;
+
+err_free_msg:
+	devm_kfree(dev, ipmi->opal_msg);
+err_unregister:
+	free_irq(ipmi->irq, ipmi);
+err_dispose:
+	irq_dispose_mapping(ipmi->irq);
+err_free:
+	devm_kfree(dev, ipmi);
+	return rc;
+}
+
+static int ipmi_powernv_remove(struct platform_device *pdev)
+{
+	struct ipmi_smi_powernv *smi = dev_get_drvdata(&pdev->dev);
+
+	ipmi_unregister_smi(smi->intf);
+	free_irq(smi->irq, smi);
+	irq_dispose_mapping(smi->irq);
+
+	return 0;
+}
+
+static const struct of_device_id ipmi_powernv_match[] = {
+	{ .compatible = "ibm,opal-ipmi" },
+	{ },
+};
+
+
+static struct platform_driver powernv_ipmi_driver = {
+	.driver = {
+		.name		= "ipmi-powernv",
+		.of_match_table	= ipmi_powernv_match,
+	},
+	.probe	= ipmi_powernv_probe,
+	.remove	= ipmi_powernv_remove,
+};
+
+
+module_platform_driver(powernv_ipmi_driver);
+
+MODULE_DEVICE_TABLE(of, ipmi_powernv_match);
+MODULE_DESCRIPTION("powernv IPMI driver");
+MODULE_AUTHOR("Jeremy Kerr <jk@ozlabs.org>");
+MODULE_LICENSE("GPL");