summaryrefslogtreecommitdiffstats
path: root/drivers/char/ipmi/kcs_bmc_cdev_ipmi.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/char/ipmi/kcs_bmc_cdev_ipmi.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/char/ipmi/kcs_bmc_cdev_ipmi.c')
-rw-r--r--drivers/char/ipmi/kcs_bmc_cdev_ipmi.c568
1 files changed, 568 insertions, 0 deletions
diff --git a/drivers/char/ipmi/kcs_bmc_cdev_ipmi.c b/drivers/char/ipmi/kcs_bmc_cdev_ipmi.c
new file mode 100644
index 000000000..cf670e891
--- /dev/null
+++ b/drivers/char/ipmi/kcs_bmc_cdev_ipmi.c
@@ -0,0 +1,568 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2015-2018, Intel Corporation.
+ */
+
+#define pr_fmt(fmt) "kcs-bmc: " fmt
+
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/ipmi_bmc.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include "kcs_bmc_client.h"
+
+/* Different phases of the KCS BMC module.
+ * KCS_PHASE_IDLE:
+ * BMC should not be expecting nor sending any data.
+ * KCS_PHASE_WRITE_START:
+ * BMC is receiving a WRITE_START command from system software.
+ * KCS_PHASE_WRITE_DATA:
+ * BMC is receiving a data byte from system software.
+ * KCS_PHASE_WRITE_END_CMD:
+ * BMC is waiting a last data byte from system software.
+ * KCS_PHASE_WRITE_DONE:
+ * BMC has received the whole request from system software.
+ * KCS_PHASE_WAIT_READ:
+ * BMC is waiting the response from the upper IPMI service.
+ * KCS_PHASE_READ:
+ * BMC is transferring the response to system software.
+ * KCS_PHASE_ABORT_ERROR1:
+ * BMC is waiting error status request from system software.
+ * KCS_PHASE_ABORT_ERROR2:
+ * BMC is waiting for idle status afer error from system software.
+ * KCS_PHASE_ERROR:
+ * BMC has detected a protocol violation at the interface level.
+ */
+enum kcs_ipmi_phases {
+ KCS_PHASE_IDLE,
+
+ KCS_PHASE_WRITE_START,
+ KCS_PHASE_WRITE_DATA,
+ KCS_PHASE_WRITE_END_CMD,
+ KCS_PHASE_WRITE_DONE,
+
+ KCS_PHASE_WAIT_READ,
+ KCS_PHASE_READ,
+
+ KCS_PHASE_ABORT_ERROR1,
+ KCS_PHASE_ABORT_ERROR2,
+ KCS_PHASE_ERROR
+};
+
+/* IPMI 2.0 - Table 9-4, KCS Interface Status Codes */
+enum kcs_ipmi_errors {
+ KCS_NO_ERROR = 0x00,
+ KCS_ABORTED_BY_COMMAND = 0x01,
+ KCS_ILLEGAL_CONTROL_CODE = 0x02,
+ KCS_LENGTH_ERROR = 0x06,
+ KCS_UNSPECIFIED_ERROR = 0xFF
+};
+
+struct kcs_bmc_ipmi {
+ struct list_head entry;
+
+ struct kcs_bmc_client client;
+
+ spinlock_t lock;
+
+ enum kcs_ipmi_phases phase;
+ enum kcs_ipmi_errors error;
+
+ wait_queue_head_t queue;
+ bool data_in_avail;
+ int data_in_idx;
+ u8 *data_in;
+
+ int data_out_idx;
+ int data_out_len;
+ u8 *data_out;
+
+ struct mutex mutex;
+ u8 *kbuffer;
+
+ struct miscdevice miscdev;
+};
+
+#define DEVICE_NAME "ipmi-kcs"
+
+#define KCS_MSG_BUFSIZ 1000
+
+#define KCS_ZERO_DATA 0
+
+/* IPMI 2.0 - Table 9-1, KCS Interface Status Register Bits */
+#define KCS_STATUS_STATE(state) (state << 6)
+#define KCS_STATUS_STATE_MASK GENMASK(7, 6)
+#define KCS_STATUS_CMD_DAT BIT(3)
+#define KCS_STATUS_SMS_ATN BIT(2)
+#define KCS_STATUS_IBF BIT(1)
+#define KCS_STATUS_OBF BIT(0)
+
+/* IPMI 2.0 - Table 9-2, KCS Interface State Bits */
+enum kcs_states {
+ IDLE_STATE = 0,
+ READ_STATE = 1,
+ WRITE_STATE = 2,
+ ERROR_STATE = 3,
+};
+
+/* IPMI 2.0 - Table 9-3, KCS Interface Control Codes */
+#define KCS_CMD_GET_STATUS_ABORT 0x60
+#define KCS_CMD_WRITE_START 0x61
+#define KCS_CMD_WRITE_END 0x62
+#define KCS_CMD_READ_BYTE 0x68
+
+static inline void set_state(struct kcs_bmc_ipmi *priv, u8 state)
+{
+ kcs_bmc_update_status(priv->client.dev, KCS_STATUS_STATE_MASK, KCS_STATUS_STATE(state));
+}
+
+static void kcs_bmc_ipmi_force_abort(struct kcs_bmc_ipmi *priv)
+{
+ set_state(priv, ERROR_STATE);
+ kcs_bmc_read_data(priv->client.dev);
+ kcs_bmc_write_data(priv->client.dev, KCS_ZERO_DATA);
+
+ priv->phase = KCS_PHASE_ERROR;
+ priv->data_in_avail = false;
+ priv->data_in_idx = 0;
+}
+
+static void kcs_bmc_ipmi_handle_data(struct kcs_bmc_ipmi *priv)
+{
+ struct kcs_bmc_device *dev;
+ u8 data;
+
+ dev = priv->client.dev;
+
+ switch (priv->phase) {
+ case KCS_PHASE_WRITE_START:
+ priv->phase = KCS_PHASE_WRITE_DATA;
+ fallthrough;
+
+ case KCS_PHASE_WRITE_DATA:
+ if (priv->data_in_idx < KCS_MSG_BUFSIZ) {
+ set_state(priv, WRITE_STATE);
+ kcs_bmc_write_data(dev, KCS_ZERO_DATA);
+ priv->data_in[priv->data_in_idx++] = kcs_bmc_read_data(dev);
+ } else {
+ kcs_bmc_ipmi_force_abort(priv);
+ priv->error = KCS_LENGTH_ERROR;
+ }
+ break;
+
+ case KCS_PHASE_WRITE_END_CMD:
+ if (priv->data_in_idx < KCS_MSG_BUFSIZ) {
+ set_state(priv, READ_STATE);
+ priv->data_in[priv->data_in_idx++] = kcs_bmc_read_data(dev);
+ priv->phase = KCS_PHASE_WRITE_DONE;
+ priv->data_in_avail = true;
+ wake_up_interruptible(&priv->queue);
+ } else {
+ kcs_bmc_ipmi_force_abort(priv);
+ priv->error = KCS_LENGTH_ERROR;
+ }
+ break;
+
+ case KCS_PHASE_READ:
+ if (priv->data_out_idx == priv->data_out_len)
+ set_state(priv, IDLE_STATE);
+
+ data = kcs_bmc_read_data(dev);
+ if (data != KCS_CMD_READ_BYTE) {
+ set_state(priv, ERROR_STATE);
+ kcs_bmc_write_data(dev, KCS_ZERO_DATA);
+ break;
+ }
+
+ if (priv->data_out_idx == priv->data_out_len) {
+ kcs_bmc_write_data(dev, KCS_ZERO_DATA);
+ priv->phase = KCS_PHASE_IDLE;
+ break;
+ }
+
+ kcs_bmc_write_data(dev, priv->data_out[priv->data_out_idx++]);
+ break;
+
+ case KCS_PHASE_ABORT_ERROR1:
+ set_state(priv, READ_STATE);
+ kcs_bmc_read_data(dev);
+ kcs_bmc_write_data(dev, priv->error);
+ priv->phase = KCS_PHASE_ABORT_ERROR2;
+ break;
+
+ case KCS_PHASE_ABORT_ERROR2:
+ set_state(priv, IDLE_STATE);
+ kcs_bmc_read_data(dev);
+ kcs_bmc_write_data(dev, KCS_ZERO_DATA);
+ priv->phase = KCS_PHASE_IDLE;
+ break;
+
+ default:
+ kcs_bmc_ipmi_force_abort(priv);
+ break;
+ }
+}
+
+static void kcs_bmc_ipmi_handle_cmd(struct kcs_bmc_ipmi *priv)
+{
+ u8 cmd;
+
+ set_state(priv, WRITE_STATE);
+ kcs_bmc_write_data(priv->client.dev, KCS_ZERO_DATA);
+
+ cmd = kcs_bmc_read_data(priv->client.dev);
+ switch (cmd) {
+ case KCS_CMD_WRITE_START:
+ priv->phase = KCS_PHASE_WRITE_START;
+ priv->error = KCS_NO_ERROR;
+ priv->data_in_avail = false;
+ priv->data_in_idx = 0;
+ break;
+
+ case KCS_CMD_WRITE_END:
+ if (priv->phase != KCS_PHASE_WRITE_DATA) {
+ kcs_bmc_ipmi_force_abort(priv);
+ break;
+ }
+
+ priv->phase = KCS_PHASE_WRITE_END_CMD;
+ break;
+
+ case KCS_CMD_GET_STATUS_ABORT:
+ if (priv->error == KCS_NO_ERROR)
+ priv->error = KCS_ABORTED_BY_COMMAND;
+
+ priv->phase = KCS_PHASE_ABORT_ERROR1;
+ priv->data_in_avail = false;
+ priv->data_in_idx = 0;
+ break;
+
+ default:
+ kcs_bmc_ipmi_force_abort(priv);
+ priv->error = KCS_ILLEGAL_CONTROL_CODE;
+ break;
+ }
+}
+
+static inline struct kcs_bmc_ipmi *client_to_kcs_bmc_ipmi(struct kcs_bmc_client *client)
+{
+ return container_of(client, struct kcs_bmc_ipmi, client);
+}
+
+static irqreturn_t kcs_bmc_ipmi_event(struct kcs_bmc_client *client)
+{
+ struct kcs_bmc_ipmi *priv;
+ u8 status;
+ int ret;
+
+ priv = client_to_kcs_bmc_ipmi(client);
+ if (!priv)
+ return IRQ_NONE;
+
+ spin_lock(&priv->lock);
+
+ status = kcs_bmc_read_status(client->dev);
+ if (status & KCS_STATUS_IBF) {
+ if (status & KCS_STATUS_CMD_DAT)
+ kcs_bmc_ipmi_handle_cmd(priv);
+ else
+ kcs_bmc_ipmi_handle_data(priv);
+
+ ret = IRQ_HANDLED;
+ } else {
+ ret = IRQ_NONE;
+ }
+
+ spin_unlock(&priv->lock);
+
+ return ret;
+}
+
+static const struct kcs_bmc_client_ops kcs_bmc_ipmi_client_ops = {
+ .event = kcs_bmc_ipmi_event,
+};
+
+static inline struct kcs_bmc_ipmi *to_kcs_bmc(struct file *filp)
+{
+ return container_of(filp->private_data, struct kcs_bmc_ipmi, miscdev);
+}
+
+static int kcs_bmc_ipmi_open(struct inode *inode, struct file *filp)
+{
+ struct kcs_bmc_ipmi *priv = to_kcs_bmc(filp);
+
+ return kcs_bmc_enable_device(priv->client.dev, &priv->client);
+}
+
+static __poll_t kcs_bmc_ipmi_poll(struct file *filp, poll_table *wait)
+{
+ struct kcs_bmc_ipmi *priv = to_kcs_bmc(filp);
+ __poll_t mask = 0;
+
+ poll_wait(filp, &priv->queue, wait);
+
+ spin_lock_irq(&priv->lock);
+ if (priv->data_in_avail)
+ mask |= EPOLLIN;
+ spin_unlock_irq(&priv->lock);
+
+ return mask;
+}
+
+static ssize_t kcs_bmc_ipmi_read(struct file *filp, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct kcs_bmc_ipmi *priv = to_kcs_bmc(filp);
+ bool data_avail;
+ size_t data_len;
+ ssize_t ret;
+
+ if (!(filp->f_flags & O_NONBLOCK))
+ wait_event_interruptible(priv->queue,
+ priv->data_in_avail);
+
+ mutex_lock(&priv->mutex);
+
+ spin_lock_irq(&priv->lock);
+ data_avail = priv->data_in_avail;
+ if (data_avail) {
+ data_len = priv->data_in_idx;
+ memcpy(priv->kbuffer, priv->data_in, data_len);
+ }
+ spin_unlock_irq(&priv->lock);
+
+ if (!data_avail) {
+ ret = -EAGAIN;
+ goto out_unlock;
+ }
+
+ if (count < data_len) {
+ pr_err("channel=%u with too large data : %zu\n",
+ priv->client.dev->channel, data_len);
+
+ spin_lock_irq(&priv->lock);
+ kcs_bmc_ipmi_force_abort(priv);
+ spin_unlock_irq(&priv->lock);
+
+ ret = -EOVERFLOW;
+ goto out_unlock;
+ }
+
+ if (copy_to_user(buf, priv->kbuffer, data_len)) {
+ ret = -EFAULT;
+ goto out_unlock;
+ }
+
+ ret = data_len;
+
+ spin_lock_irq(&priv->lock);
+ if (priv->phase == KCS_PHASE_WRITE_DONE) {
+ priv->phase = KCS_PHASE_WAIT_READ;
+ priv->data_in_avail = false;
+ priv->data_in_idx = 0;
+ } else {
+ ret = -EAGAIN;
+ }
+ spin_unlock_irq(&priv->lock);
+
+out_unlock:
+ mutex_unlock(&priv->mutex);
+
+ return ret;
+}
+
+static ssize_t kcs_bmc_ipmi_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct kcs_bmc_ipmi *priv = to_kcs_bmc(filp);
+ ssize_t ret;
+
+ /* a minimum response size '3' : netfn + cmd + ccode */
+ if (count < 3 || count > KCS_MSG_BUFSIZ)
+ return -EINVAL;
+
+ mutex_lock(&priv->mutex);
+
+ if (copy_from_user(priv->kbuffer, buf, count)) {
+ ret = -EFAULT;
+ goto out_unlock;
+ }
+
+ spin_lock_irq(&priv->lock);
+ if (priv->phase == KCS_PHASE_WAIT_READ) {
+ priv->phase = KCS_PHASE_READ;
+ priv->data_out_idx = 1;
+ priv->data_out_len = count;
+ memcpy(priv->data_out, priv->kbuffer, count);
+ kcs_bmc_write_data(priv->client.dev, priv->data_out[0]);
+ ret = count;
+ } else {
+ ret = -EINVAL;
+ }
+ spin_unlock_irq(&priv->lock);
+
+out_unlock:
+ mutex_unlock(&priv->mutex);
+
+ return ret;
+}
+
+static long kcs_bmc_ipmi_ioctl(struct file *filp, unsigned int cmd,
+ unsigned long arg)
+{
+ struct kcs_bmc_ipmi *priv = to_kcs_bmc(filp);
+ long ret = 0;
+
+ spin_lock_irq(&priv->lock);
+
+ switch (cmd) {
+ case IPMI_BMC_IOCTL_SET_SMS_ATN:
+ kcs_bmc_update_status(priv->client.dev, KCS_STATUS_SMS_ATN, KCS_STATUS_SMS_ATN);
+ break;
+
+ case IPMI_BMC_IOCTL_CLEAR_SMS_ATN:
+ kcs_bmc_update_status(priv->client.dev, KCS_STATUS_SMS_ATN, 0);
+ break;
+
+ case IPMI_BMC_IOCTL_FORCE_ABORT:
+ kcs_bmc_ipmi_force_abort(priv);
+ break;
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ spin_unlock_irq(&priv->lock);
+
+ return ret;
+}
+
+static int kcs_bmc_ipmi_release(struct inode *inode, struct file *filp)
+{
+ struct kcs_bmc_ipmi *priv = to_kcs_bmc(filp);
+
+ kcs_bmc_ipmi_force_abort(priv);
+ kcs_bmc_disable_device(priv->client.dev, &priv->client);
+
+ return 0;
+}
+
+static const struct file_operations kcs_bmc_ipmi_fops = {
+ .owner = THIS_MODULE,
+ .open = kcs_bmc_ipmi_open,
+ .read = kcs_bmc_ipmi_read,
+ .write = kcs_bmc_ipmi_write,
+ .release = kcs_bmc_ipmi_release,
+ .poll = kcs_bmc_ipmi_poll,
+ .unlocked_ioctl = kcs_bmc_ipmi_ioctl,
+};
+
+static DEFINE_SPINLOCK(kcs_bmc_ipmi_instances_lock);
+static LIST_HEAD(kcs_bmc_ipmi_instances);
+
+static int kcs_bmc_ipmi_add_device(struct kcs_bmc_device *kcs_bmc)
+{
+ struct kcs_bmc_ipmi *priv;
+ int rc;
+
+ priv = devm_kzalloc(kcs_bmc->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ spin_lock_init(&priv->lock);
+ mutex_init(&priv->mutex);
+
+ init_waitqueue_head(&priv->queue);
+
+ priv->client.dev = kcs_bmc;
+ priv->client.ops = &kcs_bmc_ipmi_client_ops;
+ priv->data_in = devm_kmalloc(kcs_bmc->dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
+ priv->data_out = devm_kmalloc(kcs_bmc->dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
+ priv->kbuffer = devm_kmalloc(kcs_bmc->dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
+
+ priv->miscdev.minor = MISC_DYNAMIC_MINOR;
+ priv->miscdev.name = devm_kasprintf(kcs_bmc->dev, GFP_KERNEL, "%s%u", DEVICE_NAME,
+ kcs_bmc->channel);
+ if (!priv->data_in || !priv->data_out || !priv->kbuffer || !priv->miscdev.name)
+ return -EINVAL;
+
+ priv->miscdev.fops = &kcs_bmc_ipmi_fops;
+
+ rc = misc_register(&priv->miscdev);
+ if (rc) {
+ dev_err(kcs_bmc->dev, "Unable to register device: %d\n", rc);
+ return rc;
+ }
+
+ spin_lock_irq(&kcs_bmc_ipmi_instances_lock);
+ list_add(&priv->entry, &kcs_bmc_ipmi_instances);
+ spin_unlock_irq(&kcs_bmc_ipmi_instances_lock);
+
+ dev_info(kcs_bmc->dev, "Initialised IPMI client for channel %d", kcs_bmc->channel);
+
+ return 0;
+}
+
+static int kcs_bmc_ipmi_remove_device(struct kcs_bmc_device *kcs_bmc)
+{
+ struct kcs_bmc_ipmi *priv = NULL, *pos;
+
+ spin_lock_irq(&kcs_bmc_ipmi_instances_lock);
+ list_for_each_entry(pos, &kcs_bmc_ipmi_instances, entry) {
+ if (pos->client.dev == kcs_bmc) {
+ priv = pos;
+ list_del(&pos->entry);
+ break;
+ }
+ }
+ spin_unlock_irq(&kcs_bmc_ipmi_instances_lock);
+
+ if (!priv)
+ return -ENODEV;
+
+ misc_deregister(&priv->miscdev);
+ kcs_bmc_disable_device(priv->client.dev, &priv->client);
+ devm_kfree(kcs_bmc->dev, priv->kbuffer);
+ devm_kfree(kcs_bmc->dev, priv->data_out);
+ devm_kfree(kcs_bmc->dev, priv->data_in);
+ devm_kfree(kcs_bmc->dev, priv);
+
+ return 0;
+}
+
+static const struct kcs_bmc_driver_ops kcs_bmc_ipmi_driver_ops = {
+ .add_device = kcs_bmc_ipmi_add_device,
+ .remove_device = kcs_bmc_ipmi_remove_device,
+};
+
+static struct kcs_bmc_driver kcs_bmc_ipmi_driver = {
+ .ops = &kcs_bmc_ipmi_driver_ops,
+};
+
+static int __init kcs_bmc_ipmi_init(void)
+{
+ kcs_bmc_register_driver(&kcs_bmc_ipmi_driver);
+
+ return 0;
+}
+module_init(kcs_bmc_ipmi_init);
+
+static void __exit kcs_bmc_ipmi_exit(void)
+{
+ kcs_bmc_unregister_driver(&kcs_bmc_ipmi_driver);
+}
+module_exit(kcs_bmc_ipmi_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Haiyue Wang <haiyue.wang@linux.intel.com>");
+MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
+MODULE_DESCRIPTION("KCS BMC to handle the IPMI request from system software");