blob: 845efa0f724f03158696fd32426ca470b721adbc [file] [log] [blame]
/*
* PowerNV OPAL IPMI driver
*
* Copyright 2014 IBM Corp.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*/
#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_device_id ipmi_id;
ipmi_smi_t 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, ipmi_smi_t 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;
}
/* todo: query actual ipmi_device_id */
rc = ipmi_register_smi(&ipmi_powernv_smi_handlers, ipmi,
&ipmi->ipmi_id, 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");