HP iLO driver

A driver for the HP iLO/iLO2 management processor, which allows userspace
programs to query the management processor.  Programs can open a channel
to the device (/dev/hpilo/dXccbN), and use this to send/receive queries.  
The O_EXCL open flag is used to indicate that a particular channel cannot
be shared between processes.  This driver will replace various packages
HP has shipped, including hprsm and hp-ilo.

Signed-off-by: David Altobelli <david.altobelli@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

4 files changed, 971 insertions, 0 deletions

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 1921b8dbb242..ce67d973d349 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -420,4 +420,17 @@ config SGI_XP
           this feature will allow for direct communication between SSIs
           based on a network adapter and DMA messaging.
 
+config HP_ILO
+        tristate "Channel interface driver for HP iLO/iLO2 processor"
+        default n
+        help
+          The channel interface driver allows applications to communicate
+          with iLO/iLO2 management processors present on HP ProLiant
+          servers.  Upon loading, the driver creates /dev/hpilo/dXccbN files,
+          which can be used to gather data from the management processor,
+          via read and write system calls.
+
+          To compile this driver as a module, choose M here: the
+          module will be called hpilo.
+
 endif # MISC_DEVICES
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index a6dac6a2e7e5..688fe76135e0 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -27,3 +27,4 @@ obj-$(CONFIG_INTEL_MENLOW)	+= intel_menlow.o
 obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
 obj-$(CONFIG_KGDB_TESTS)        += kgdbts.o
 obj-$(CONFIG_SGI_XP)            += sgi-xp/
+obj-$(CONFIG_HP_ILO)            += hpilo.o
diff --git a/drivers/misc/hpilo.c b/drivers/misc/hpilo.c
new file mode 100644
index 000000000000..05e298289238
--- /dev/null
+++ b/drivers/misc/hpilo.c
@@ -0,0 +1,768 @@
+/*
+ * Driver for HP iLO/iLO2 management processor.
+ *
+ * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
+ *      David Altobelli <david.altobelli@hp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+#include <linux/file.h>
+#include <linux/cdev.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include "hpilo.h"
+
+static struct class *ilo_class;
+static unsigned int ilo_major;
+static char ilo_hwdev[MAX_ILO_DEV];
+
+static inline int get_entry_id(int entry)
+{
+        return (entry & ENTRY_MASK_DESCRIPTOR) >> ENTRY_BITPOS_DESCRIPTOR;
+}
+
+static inline int get_entry_len(int entry)
+{
+        return ((entry & ENTRY_MASK_QWORDS) >> ENTRY_BITPOS_QWORDS) << 3;
+}
+
+static inline int mk_entry(int id, int len)
+{
+        int qlen = len & 7 ? (len >> 3) + 1 : len >> 3;
+        return id << ENTRY_BITPOS_DESCRIPTOR | qlen << ENTRY_BITPOS_QWORDS;
+}
+
+static inline int desc_mem_sz(int nr_entry)
+{
+        return nr_entry << L2_QENTRY_SZ;
+}
+
+/*
+ * FIFO queues, shared with hardware.
+ *
+ * If a queue has empty slots, an entry is added to the queue tail,
+ * and that entry is marked as occupied.
+ * Entries can be dequeued from the head of the list, when the device
+ * has marked the entry as consumed.
+ *
+ * Returns true on successful queue/dequeue, false on failure.
+ */
+static int fifo_enqueue(struct ilo_hwinfo *hw, char *fifobar, int entry)
+{
+        struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
+        int ret = 0;
+
+        spin_lock(&hw->fifo_lock);
+        if (!(fifo_q->fifobar[(fifo_q->tail + 1) & fifo_q->imask]
+              & ENTRY_MASK_O)) {
+                fifo_q->fifobar[fifo_q->tail & fifo_q->imask] |=
+                                (entry & ENTRY_MASK_NOSTATE) | fifo_q->merge;
+                fifo_q->tail += 1;
+                ret = 1;
+        }
+        spin_unlock(&hw->fifo_lock);
+
+        return ret;
+}
+
+static int fifo_dequeue(struct ilo_hwinfo *hw, char *fifobar, int *entry)
+{
+        struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
+        int ret = 0;
+        u64 c;
+
+        spin_lock(&hw->fifo_lock);
+        c = fifo_q->fifobar[fifo_q->head & fifo_q->imask];
+        if (c & ENTRY_MASK_C) {
+                if (entry)
+                        *entry = c & ENTRY_MASK_NOSTATE;
+
+                fifo_q->fifobar[fifo_q->head & fifo_q->imask] =
+                                                        (c | ENTRY_MASK) + 1;
+                fifo_q->head += 1;
+                ret = 1;
+        }
+        spin_unlock(&hw->fifo_lock);
+
+        return ret;
+}
+
+static int ilo_pkt_enqueue(struct ilo_hwinfo *hw, struct ccb *ccb,
+                           int dir, int id, int len)
+{
+        char *fifobar;
+        int entry;
+
+        if (dir == SENDQ)
+                fifobar = ccb->ccb_u1.send_fifobar;
+        else
+                fifobar = ccb->ccb_u3.recv_fifobar;
+
+        entry = mk_entry(id, len);
+        return fifo_enqueue(hw, fifobar, entry);
+}
+
+static int ilo_pkt_dequeue(struct ilo_hwinfo *hw, struct ccb *ccb,
+                           int dir, int *id, int *len, void **pkt)
+{
+        char *fifobar, *desc;
+        int entry = 0, pkt_id = 0;
+        int ret;
+
+        if (dir == SENDQ) {
+                fifobar = ccb->ccb_u1.send_fifobar;
+                desc = ccb->ccb_u2.send_desc;
+        } else {
+                fifobar = ccb->ccb_u3.recv_fifobar;
+                desc = ccb->ccb_u4.recv_desc;
+        }
+
+        ret = fifo_dequeue(hw, fifobar, &entry);
+        if (ret) {
+                pkt_id = get_entry_id(entry);
+                if (id)
+                        *id = pkt_id;
+                if (len)
+                        *len = get_entry_len(entry);
+                if (pkt)
+                        *pkt = (void *)(desc + desc_mem_sz(pkt_id));
+        }
+
+        return ret;
+}
+
+static inline void doorbell_set(struct ccb *ccb)
+{
+        iowrite8(1, ccb->ccb_u5.db_base);
+}
+
+static inline void doorbell_clr(struct ccb *ccb)
+{
+        iowrite8(2, ccb->ccb_u5.db_base);
+}
+static inline int ctrl_set(int l2sz, int idxmask, int desclim)
+{
+        int active = 0, go = 1;
+        return l2sz << CTRL_BITPOS_L2SZ |
+               idxmask << CTRL_BITPOS_FIFOINDEXMASK |
+               desclim << CTRL_BITPOS_DESCLIMIT |
+               active << CTRL_BITPOS_A |
+               go << CTRL_BITPOS_G;
+}
+static void ctrl_setup(struct ccb *ccb, int nr_desc, int l2desc_sz)
+{
+        /* for simplicity, use the same parameters for send and recv ctrls */
+        ccb->send_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
+        ccb->recv_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
+}
+
+static inline int fifo_sz(int nr_entry)
+{
+        /* size of a fifo is determined by the number of entries it contains */
+        return (nr_entry * sizeof(u64)) + FIFOHANDLESIZE;
+}
+
+static void fifo_setup(void *base_addr, int nr_entry)
+{
+        struct fifo *fifo_q = base_addr;
+        int i;
+
+        /* set up an empty fifo */
+        fifo_q->head = 0;
+        fifo_q->tail = 0;
+        fifo_q->reset = 0;
+        fifo_q->nrents = nr_entry;
+        fifo_q->imask = nr_entry - 1;
+        fifo_q->merge = ENTRY_MASK_O;
+
+        for (i = 0; i < nr_entry; i++)
+                fifo_q->fifobar[i] = 0;
+}
+
+static void ilo_ccb_close(struct pci_dev *pdev, struct ccb_data *data)
+{
+        struct ccb *driver_ccb;
+        struct ccb __iomem *device_ccb;
+        int retries;
+
+        driver_ccb = &data->driver_ccb;
+        device_ccb = data->mapped_ccb;
+
+        /* complicated dance to tell the hw we are stopping */
+        doorbell_clr(driver_ccb);
+        iowrite32(ioread32(&device_ccb->send_ctrl) & ~(1 << CTRL_BITPOS_G),
+                  &device_ccb->send_ctrl);
+        iowrite32(ioread32(&device_ccb->recv_ctrl) & ~(1 << CTRL_BITPOS_G),
+                  &device_ccb->recv_ctrl);
+
+        /* give iLO some time to process stop request */
+        for (retries = 1000; retries > 0; retries--) {
+                doorbell_set(driver_ccb);
+                udelay(1);
+                if (!(ioread32(&device_ccb->send_ctrl) & (1 << CTRL_BITPOS_A))
+                    &&
+                    !(ioread32(&device_ccb->recv_ctrl) & (1 << CTRL_BITPOS_A)))
+                        break;
+        }
+        if (retries == 0)
+                dev_err(&pdev->dev, "Closing, but controller still active\n");
+
+        /* clear the hw ccb */
+        memset_io(device_ccb, 0, sizeof(struct ccb));
+
+        /* free resources used to back send/recv queues */
+        pci_free_consistent(pdev, data->dma_size, data->dma_va, data->dma_pa);
+}
+
+static int ilo_ccb_open(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)
+{
+        char *dma_va, *dma_pa;
+        int pkt_id, pkt_sz, i, error;
+        struct ccb *driver_ccb, *ilo_ccb;
+        struct pci_dev *pdev;
+
+        driver_ccb = &data->driver_ccb;
+        ilo_ccb = &data->ilo_ccb;
+        pdev = hw->ilo_dev;
+
+        data->dma_size = 2 * fifo_sz(NR_QENTRY) +
+                         2 * desc_mem_sz(NR_QENTRY) +
+                         ILO_START_ALIGN + ILO_CACHE_SZ;
+
+        error = -ENOMEM;
+        data->dma_va = pci_alloc_consistent(pdev, data->dma_size,
+                                            &data->dma_pa);
+        if (!data->dma_va)
+                goto out;
+
+        dma_va = (char *)data->dma_va;
+        dma_pa = (char *)data->dma_pa;
+
+        memset(dma_va, 0, data->dma_size);
+
+        dma_va = (char *)roundup((unsigned long)dma_va, ILO_START_ALIGN);
+        dma_pa = (char *)roundup((unsigned long)dma_pa, ILO_START_ALIGN);
+
+        /*
+         * Create two ccb's, one with virt addrs, one with phys addrs.
+         * Copy the phys addr ccb to device shared mem.
+         */
+        ctrl_setup(driver_ccb, NR_QENTRY, L2_QENTRY_SZ);
+        ctrl_setup(ilo_ccb, NR_QENTRY, L2_QENTRY_SZ);
+
+        fifo_setup(dma_va, NR_QENTRY);
+        driver_ccb->ccb_u1.send_fifobar = dma_va + FIFOHANDLESIZE;
+        ilo_ccb->ccb_u1.send_fifobar = dma_pa + FIFOHANDLESIZE;
+        dma_va += fifo_sz(NR_QENTRY);
+        dma_pa += fifo_sz(NR_QENTRY);
+
+        dma_va = (char *)roundup((unsigned long)dma_va, ILO_CACHE_SZ);
+        dma_pa = (char *)roundup((unsigned long)dma_pa, ILO_CACHE_SZ);
+
+        fifo_setup(dma_va, NR_QENTRY);
+        driver_ccb->ccb_u3.recv_fifobar = dma_va + FIFOHANDLESIZE;
+        ilo_ccb->ccb_u3.recv_fifobar = dma_pa + FIFOHANDLESIZE;
+        dma_va += fifo_sz(NR_QENTRY);
+        dma_pa += fifo_sz(NR_QENTRY);
+
+        driver_ccb->ccb_u2.send_desc = dma_va;
+        ilo_ccb->ccb_u2.send_desc = dma_pa;
+        dma_pa += desc_mem_sz(NR_QENTRY);
+        dma_va += desc_mem_sz(NR_QENTRY);
+
+        driver_ccb->ccb_u4.recv_desc = dma_va;
+        ilo_ccb->ccb_u4.recv_desc = dma_pa;
+
+        driver_ccb->channel = slot;
+        ilo_ccb->channel = slot;
+
+        driver_ccb->ccb_u5.db_base = hw->db_vaddr + (slot << L2_DB_SIZE);
+        ilo_ccb->ccb_u5.db_base = NULL; /* hw ccb's doorbell is not used */
+
+        /* copy the ccb with physical addrs to device memory */
+        data->mapped_ccb = (struct ccb __iomem *)
+                                (hw->ram_vaddr + (slot * ILOHW_CCB_SZ));
+        memcpy_toio(data->mapped_ccb, ilo_ccb, sizeof(struct ccb));
+
+        /* put packets on the send and receive queues */
+        pkt_sz = 0;
+        for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++) {
+                ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, pkt_sz);
+                doorbell_set(driver_ccb);
+        }
+
+        pkt_sz = desc_mem_sz(1);
+        for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++)
+                ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, pkt_sz);
+
+        doorbell_clr(driver_ccb);
+
+        /* make sure iLO is really handling requests */
+        for (i = 1000; i > 0; i--) {
+                if (ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, NULL, NULL))
+                        break;
+                udelay(1);
+        }
+
+        if (i) {
+                ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, 0);
+                doorbell_set(driver_ccb);
+        } else {
+                dev_err(&pdev->dev, "Open could not dequeue a packet\n");
+                error = -EBUSY;
+                goto free;
+        }
+
+        return 0;
+free:
+        pci_free_consistent(pdev, data->dma_size, data->dma_va, data->dma_pa);
+out:
+        return error;
+}
+
+static inline int is_channel_reset(struct ccb *ccb)
+{
+        /* check for this particular channel needing a reset */
+        return FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset;
+}
+
+static inline void set_channel_reset(struct ccb *ccb)
+{
+        /* set a flag indicating this channel needs a reset */
+        FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset = 1;
+}
+
+static inline int is_device_reset(struct ilo_hwinfo *hw)
+{
+        /* check for global reset condition */
+        return ioread32(&hw->mmio_vaddr[DB_OUT]) & (1 << DB_RESET);
+}
+
+static inline void clear_device(struct ilo_hwinfo *hw)
+{
+        /* clear the device (reset bits, pending channel entries) */
+        iowrite32(-1, &hw->mmio_vaddr[DB_OUT]);
+}
+
+static void ilo_locked_reset(struct ilo_hwinfo *hw)
+{
+        int slot;
+
+        /*
+         * Mapped memory is zeroed on ilo reset, so set a per ccb flag
+         * to indicate that this ccb needs to be closed and reopened.
+         */
+        for (slot = 0; slot < MAX_CCB; slot++) {
+                if (!hw->ccb_alloc[slot])
+                        continue;
+                set_channel_reset(&hw->ccb_alloc[slot]->driver_ccb);
+        }
+
+        clear_device(hw);
+}
+
+static void ilo_reset(struct ilo_hwinfo *hw)
+{
+        spin_lock(&hw->alloc_lock);
+
+        /* reset might have been handled after lock was taken */
+        if (is_device_reset(hw))
+                ilo_locked_reset(hw);
+
+        spin_unlock(&hw->alloc_lock);
+}
+
+static ssize_t ilo_read(struct file *fp, char __user *buf,
+                        size_t len, loff_t *off)
+{
+        int err, found, cnt, pkt_id, pkt_len;
+        struct ccb_data *data;
+        struct ccb *driver_ccb;
+        struct ilo_hwinfo *hw;
+        void *pkt;
+
+        data = fp->private_data;
+        driver_ccb = &data->driver_ccb;
+        hw = data->ilo_hw;
+
+        if (is_device_reset(hw) || is_channel_reset(driver_ccb)) {
+                /*
+                 * If the device has been reset, applications
+                 * need to close and reopen all ccbs.
+                 */
+                ilo_reset(hw);
+                return -ENODEV;
+        }
+
+        /*
+         * This function is to be called when data is expected
+         * in the channel, and will return an error if no packet is found
+         * during the loop below.  The sleep/retry logic is to allow
+         * applications to call read() immediately post write(),
+         * and give iLO some time to process the sent packet.
+         */
+        cnt = 20;
+        do {
+                /* look for a received packet */
+                found = ilo_pkt_dequeue(hw, driver_ccb, RECVQ, &pkt_id,
+                                        &pkt_len, &pkt);
+                if (found)
+                        break;
+                cnt--;
+                msleep(100);
+        } while (!found && cnt);
+
+        if (!found)
+                return -EAGAIN;
+
+        /* only copy the length of the received packet */
+        if (pkt_len < len)
+                len = pkt_len;
+
+        err = copy_to_user(buf, pkt, len);
+
+        /* return the received packet to the queue */
+        ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, desc_mem_sz(1));
+
+        return err ? -EFAULT : len;
+}
+
+static ssize_t ilo_write(struct file *fp, const char __user *buf,
+                         size_t len, loff_t *off)
+{
+        int err, pkt_id, pkt_len;
+        struct ccb_data *data;
+        struct ccb *driver_ccb;
+        struct ilo_hwinfo *hw;
+        void *pkt;
+
+        data = fp->private_data;
+        driver_ccb = &data->driver_ccb;
+        hw = data->ilo_hw;
+
+        if (is_device_reset(hw) || is_channel_reset(driver_ccb)) {
+                /*
+                 * If the device has been reset, applications
+                 * need to close and reopen all ccbs.
+                 */
+                ilo_reset(hw);
+                return -ENODEV;
+        }
+
+        /* get a packet to send the user command */
+        if (!ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, &pkt_len, &pkt))
+                return -EBUSY;
+
+        /* limit the length to the length of the packet */
+        if (pkt_len < len)
+                len = pkt_len;
+
+        /* on failure, set the len to 0 to return empty packet to the device */
+        err = copy_from_user(pkt, buf, len);
+        if (err)
+                len = 0;
+
+        /* send the packet */
+        ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, len);
+        doorbell_set(driver_ccb);
+
+        return err ? -EFAULT : len;
+}
+
+static int ilo_close(struct inode *ip, struct file *fp)
+{
+        int slot;
+        struct ccb_data *data;
+        struct ilo_hwinfo *hw;
+
+        slot = iminor(ip) % MAX_CCB;
+        hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
+
+        spin_lock(&hw->alloc_lock);
+
+        if (is_device_reset(hw))
+                ilo_locked_reset(hw);
+
+        if (hw->ccb_alloc[slot]->ccb_cnt == 1) {
+
+                data = fp->private_data;
+
+                ilo_ccb_close(hw->ilo_dev, data);
+
+                kfree(data);
+                hw->ccb_alloc[slot] = NULL;
+        } else
+                hw->ccb_alloc[slot]->ccb_cnt--;
+
+        spin_unlock(&hw->alloc_lock);
+
+        return 0;
+}
+
+static int ilo_open(struct inode *ip, struct file *fp)
+{
+        int slot, error;
+        struct ccb_data *data;
+        struct ilo_hwinfo *hw;
+
+        slot = iminor(ip) % MAX_CCB;
+        hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
+
+        /* new ccb allocation */
+        data = kzalloc(sizeof(*data), GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        spin_lock(&hw->alloc_lock);
+
+        if (is_device_reset(hw))
+                ilo_locked_reset(hw);
+
+        /* each fd private_data holds sw/hw view of ccb */
+        if (hw->ccb_alloc[slot] == NULL) {
+                /* create a channel control block for this minor */
+                error = ilo_ccb_open(hw, data, slot);
+                if (!error) {
+                        hw->ccb_alloc[slot] = data;
+                        hw->ccb_alloc[slot]->ccb_cnt = 1;
+                        hw->ccb_alloc[slot]->ccb_excl = fp->f_flags & O_EXCL;
+                        hw->ccb_alloc[slot]->ilo_hw = hw;
+                } else
+                        kfree(data);
+        } else {
+                kfree(data);
+                if (fp->f_flags & O_EXCL || hw->ccb_alloc[slot]->ccb_excl) {
+                        /*
+                         * The channel exists, and either this open
+                         * or a previous open of this channel wants
+                         * exclusive access.
+                         */
+                        error = -EBUSY;
+                } else {
+                        hw->ccb_alloc[slot]->ccb_cnt++;
+                        error = 0;
+                }
+        }
+        spin_unlock(&hw->alloc_lock);
+
+        if (!error)
+                fp->private_data = hw->ccb_alloc[slot];
+
+        return error;
+}
+
+static const struct file_operations ilo_fops = {
+        .owner          = THIS_MODULE,
+        .read           = ilo_read,
+        .write          = ilo_write,
+        .open           = ilo_open,
+        .release        = ilo_close,
+};
+
+static void ilo_unmap_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
+{
+        pci_iounmap(pdev, hw->db_vaddr);
+        pci_iounmap(pdev, hw->ram_vaddr);
+        pci_iounmap(pdev, hw->mmio_vaddr);
+}
+
+static int __devinit ilo_map_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
+{
+        int error = -ENOMEM;
+
+        /* map the memory mapped i/o registers */
+        hw->mmio_vaddr = pci_iomap(pdev, 1, 0);
+        if (hw->mmio_vaddr == NULL) {
+                dev_err(&pdev->dev, "Error mapping mmio\n");
+                goto out;
+        }
+
+        /* map the adapter shared memory region */
+        hw->ram_vaddr = pci_iomap(pdev, 2, MAX_CCB * ILOHW_CCB_SZ);
+        if (hw->ram_vaddr == NULL) {
+                dev_err(&pdev->dev, "Error mapping shared mem\n");
+                goto mmio_free;
+        }
+
+        /* map the doorbell aperture */
+        hw->db_vaddr = pci_iomap(pdev, 3, MAX_CCB * ONE_DB_SIZE);
+        if (hw->db_vaddr == NULL) {
+                dev_err(&pdev->dev, "Error mapping doorbell\n");
+                goto ram_free;
+        }
+
+        return 0;
+ram_free:
+        pci_iounmap(pdev, hw->ram_vaddr);
+mmio_free:
+        pci_iounmap(pdev, hw->mmio_vaddr);
+out:
+        return error;
+}
+
+static void ilo_remove(struct pci_dev *pdev)
+{
+        int i, minor;
+        struct ilo_hwinfo *ilo_hw = pci_get_drvdata(pdev);
+
+        clear_device(ilo_hw);
+
+        minor = MINOR(ilo_hw->cdev.dev);
+        for (i = minor; i < minor + MAX_CCB; i++)
+                device_destroy(ilo_class, MKDEV(ilo_major, i));
+
+        cdev_del(&ilo_hw->cdev);
+        ilo_unmap_device(pdev, ilo_hw);
+        pci_release_regions(pdev);
+        pci_disable_device(pdev);
+        kfree(ilo_hw);
+        ilo_hwdev[(minor / MAX_CCB)] = 0;
+}
+
+static int __devinit ilo_probe(struct pci_dev *pdev,
+                               const struct pci_device_id *ent)
+{
+        int devnum, minor, start, error;
+        struct ilo_hwinfo *ilo_hw;
+
+        /* find a free range for device files */
+        for (devnum = 0; devnum < MAX_ILO_DEV; devnum++) {
+                if (ilo_hwdev[devnum] == 0) {
+                        ilo_hwdev[devnum] = 1;
+                        break;
+                }
+        }
+
+        if (devnum == MAX_ILO_DEV) {
+                dev_err(&pdev->dev, "Error finding free device\n");
+                return -ENODEV;
+        }
+
+        /* track global allocations for this device */
+        error = -ENOMEM;
+        ilo_hw = kzalloc(sizeof(*ilo_hw), GFP_KERNEL);
+        if (!ilo_hw)
+                goto out;
+
+        ilo_hw->ilo_dev = pdev;
+        spin_lock_init(&ilo_hw->alloc_lock);
+        spin_lock_init(&ilo_hw->fifo_lock);
+
+        error = pci_enable_device(pdev);
+        if (error)
+                goto free;
+
+        pci_set_master(pdev);
+
+        error = pci_request_regions(pdev, ILO_NAME);
+        if (error)
+                goto disable;
+
+        error = ilo_map_device(pdev, ilo_hw);
+        if (error)
+                goto free_regions;
+
+        pci_set_drvdata(pdev, ilo_hw);
+        clear_device(ilo_hw);
+
+        cdev_init(&ilo_hw->cdev, &ilo_fops);
+        ilo_hw->cdev.owner = THIS_MODULE;
+        start = devnum * MAX_CCB;
+        error = cdev_add(&ilo_hw->cdev, MKDEV(ilo_major, start), MAX_CCB);
+        if (error) {
+                dev_err(&pdev->dev, "Could not add cdev\n");
+                goto unmap;
+        }
+
+        for (minor = 0 ; minor < MAX_CCB; minor++) {
+                struct device *dev;
+                dev = device_create(ilo_class, &pdev->dev,
+                                    MKDEV(ilo_major, minor), NULL,
+                                    "hpilo!d%dccb%d", devnum, minor);
+                if (IS_ERR(dev))
+                        dev_err(&pdev->dev, "Could not create files\n");
+        }
+
+        return 0;
+unmap:
+        ilo_unmap_device(pdev, ilo_hw);
+free_regions:
+        pci_release_regions(pdev);
+disable:
+        pci_disable_device(pdev);
+free:
+        kfree(ilo_hw);
+out:
+        ilo_hwdev[devnum] = 0;
+        return error;
+}
+
+static struct pci_device_id ilo_devices[] = {
+        { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB204) },
+        { }
+};
+MODULE_DEVICE_TABLE(pci, ilo_devices);
+
+static struct pci_driver ilo_driver = {
+        .name     = ILO_NAME,
+        .id_table = ilo_devices,
+        .probe    = ilo_probe,
+        .remove   = __devexit_p(ilo_remove),
+};
+
+static int __init ilo_init(void)
+{
+        int error;
+        dev_t dev;
+
+        ilo_class = class_create(THIS_MODULE, "iLO");
+        if (IS_ERR(ilo_class)) {
+                error = PTR_ERR(ilo_class);
+                goto out;
+        }
+
+        error = alloc_chrdev_region(&dev, 0, MAX_OPEN, ILO_NAME);
+        if (error)
+                goto class_destroy;
+
+        ilo_major = MAJOR(dev);
+
+        error = pci_register_driver(&ilo_driver);
+        if (error)
+                goto chr_remove;
+
+        return 0;
+chr_remove:
+        unregister_chrdev_region(dev, MAX_OPEN);
+class_destroy:
+        class_destroy(ilo_class);
+out:
+        return error;
+}
+
+static void __exit ilo_exit(void)
+{
+        pci_unregister_driver(&ilo_driver);
+        unregister_chrdev_region(MKDEV(ilo_major, 0), MAX_OPEN);
+        class_destroy(ilo_class);
+}
+
+MODULE_VERSION("0.05");
+MODULE_ALIAS(ILO_NAME);
+MODULE_DESCRIPTION(ILO_NAME);
+MODULE_AUTHOR("David Altobelli <david.altobelli@hp.com>");
+MODULE_LICENSE("GPL v2");
+
+module_init(ilo_init);
+module_exit(ilo_exit);
diff --git a/drivers/misc/hpilo.h b/drivers/misc/hpilo.h
new file mode 100644
index 000000000000..a281207696c1
--- /dev/null
+++ b/drivers/misc/hpilo.h
@@ -0,0 +1,189 @@
+/*
+ * linux/drivers/char/hpilo.h
+ *
+ * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
+ *      David Altobelli <david.altobelli@hp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __HPILO_H
+#define __HPILO_H
+
+#define ILO_NAME "hpilo"
+
+/* max number of open channel control blocks per device, hw limited to 32 */
+#define MAX_CCB         8
+/* max number of supported devices */
+#define MAX_ILO_DEV     1
+/* max number of files */
+#define MAX_OPEN        (MAX_CCB * MAX_ILO_DEV)
+
+/*
+ * Per device, used to track global memory allocations.
+ */
+struct ilo_hwinfo {
+        /* mmio registers on device */
+        char __iomem *mmio_vaddr;
+
+        /* doorbell registers on device */
+        char __iomem *db_vaddr;
+
+        /* shared memory on device used for channel control blocks */
+        char __iomem *ram_vaddr;
+
+        /* files corresponding to this device */
+        struct ccb_data *ccb_alloc[MAX_CCB];
+
+        struct pci_dev *ilo_dev;
+
+        spinlock_t alloc_lock;
+        spinlock_t fifo_lock;
+
+        struct cdev cdev;
+};
+
+/* offset from mmio_vaddr */
+#define DB_OUT          0xD4
+/* DB_OUT reset bit */
+#define DB_RESET        26
+
+/*
+ * Channel control block. Used to manage hardware queues.
+ * The format must match hw's version.  The hw ccb is 128 bytes,
+ * but the context area shouldn't be touched by the driver.
+ */
+#define ILOSW_CCB_SZ    64
+#define ILOHW_CCB_SZ    128
+struct ccb {
+        union {
+                char *send_fifobar;
+                u64 padding1;
+        } ccb_u1;
+        union {
+                char *send_desc;
+                u64 padding2;
+        } ccb_u2;
+        u64 send_ctrl;
+
+        union {
+                char *recv_fifobar;
+                u64 padding3;
+        } ccb_u3;
+        union {
+                char *recv_desc;
+                u64 padding4;
+        } ccb_u4;
+        u64 recv_ctrl;
+
+        union {
+                char __iomem *db_base;
+                u64 padding5;
+        } ccb_u5;
+
+        u64 channel;
+
+        /* unused context area (64 bytes) */
+};
+
+/* ccb queue parameters */
+#define SENDQ           1
+#define RECVQ           2
+#define NR_QENTRY       4
+#define L2_QENTRY_SZ    12
+
+/* ccb ctrl bitfields */
+#define CTRL_BITPOS_L2SZ             0
+#define CTRL_BITPOS_FIFOINDEXMASK    4
+#define CTRL_BITPOS_DESCLIMIT        18
+#define CTRL_BITPOS_A                30
+#define CTRL_BITPOS_G                31
+
+/* ccb doorbell macros */
+#define L2_DB_SIZE              14
+#define ONE_DB_SIZE             (1 << L2_DB_SIZE)
+
+/*
+ * Per fd structure used to track the ccb allocated to that dev file.
+ */
+struct ccb_data {
+        /* software version of ccb, using virtual addrs */
+        struct ccb  driver_ccb;
+
+        /* hardware version of ccb, using physical addrs */
+        struct ccb  ilo_ccb;
+
+        /* hardware ccb is written to this shared mapped device memory */
+        struct ccb __iomem *mapped_ccb;
+
+        /* dma'able memory used for send/recv queues */
+        void       *dma_va;
+        dma_addr_t  dma_pa;
+        size_t      dma_size;
+
+        /* pointer to hardware device info */
+        struct ilo_hwinfo *ilo_hw;
+
+        /* usage count, to allow for shared ccb's */
+        int         ccb_cnt;
+
+        /* open wanted exclusive access to this ccb */
+        int         ccb_excl;
+};
+
+/*
+ * FIFO queue structure, shared with hw.
+ */
+#define ILO_START_ALIGN 4096
+#define ILO_CACHE_SZ     128
+struct fifo {
+    u64 nrents; /* user requested number of fifo entries */
+    u64 imask;  /* mask to extract valid fifo index */
+    u64 merge;  /*  O/C bits to merge in during enqueue operation */
+    u64 reset;  /* set to non-zero when the target device resets */
+    u8  pad_0[ILO_CACHE_SZ - (sizeof(u64) * 4)];
+
+    u64 head;
+    u8  pad_1[ILO_CACHE_SZ - (sizeof(u64))];
+
+    u64 tail;
+    u8  pad_2[ILO_CACHE_SZ - (sizeof(u64))];
+
+    u64 fifobar[1];
+};
+
+/* convert between struct fifo, and the fifobar, which is saved in the ccb */
+#define FIFOHANDLESIZE (sizeof(struct fifo) - sizeof(u64))
+#define FIFOBARTOHANDLE(_fifo) \
+        ((struct fifo *)(((char *)(_fifo)) - FIFOHANDLESIZE))
+
+/* the number of qwords to consume from the entry descriptor */
+#define ENTRY_BITPOS_QWORDS      0
+/* descriptor index number (within a specified queue) */
+#define ENTRY_BITPOS_DESCRIPTOR  10
+/* state bit, fifo entry consumed by consumer */
+#define ENTRY_BITPOS_C           22
+/* state bit, fifo entry is occupied */
+#define ENTRY_BITPOS_O           23
+
+#define ENTRY_BITS_QWORDS        10
+#define ENTRY_BITS_DESCRIPTOR    12
+#define ENTRY_BITS_C             1
+#define ENTRY_BITS_O             1
+#define ENTRY_BITS_TOTAL        \
+        (ENTRY_BITS_C + ENTRY_BITS_O + \
+         ENTRY_BITS_QWORDS + ENTRY_BITS_DESCRIPTOR)
+
+/* extract various entry fields */
+#define ENTRY_MASK ((1 << ENTRY_BITS_TOTAL) - 1)
+#define ENTRY_MASK_C (((1 << ENTRY_BITS_C) - 1) << ENTRY_BITPOS_C)
+#define ENTRY_MASK_O (((1 << ENTRY_BITS_O) - 1) << ENTRY_BITPOS_O)
+#define ENTRY_MASK_QWORDS \
+        (((1 << ENTRY_BITS_QWORDS) - 1) << ENTRY_BITPOS_QWORDS)
+#define ENTRY_MASK_DESCRIPTOR \
+        (((1 << ENTRY_BITS_DESCRIPTOR) - 1) << ENTRY_BITPOS_DESCRIPTOR)
+
+#define ENTRY_MASK_NOSTATE (ENTRY_MASK >> (ENTRY_BITS_C + ENTRY_BITS_O))
+
+#endif /* __HPILO_H */