diff options
author | 2016-04-11 10:41:07 +0300 | |
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committer | 2016-04-13 08:17:18 +0300 | |
commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/powerpc/platforms/powernv/opal-prd.c | |
parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/powerpc/platforms/powernv/opal-prd.c')
-rw-r--r-- | kernel/arch/powerpc/platforms/powernv/opal-prd.c | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/platforms/powernv/opal-prd.c b/kernel/arch/powerpc/platforms/powernv/opal-prd.c new file mode 100644 index 000000000..4ece8e40d --- /dev/null +++ b/kernel/arch/powerpc/platforms/powernv/opal-prd.c @@ -0,0 +1,448 @@ +/* + * OPAL Runtime Diagnostics interface driver + * Supported on POWERNV platform + * + * Copyright IBM Corporation 2015 + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#define pr_fmt(fmt) "opal-prd: " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/miscdevice.h> +#include <linux/fs.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/poll.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <asm/opal-prd.h> +#include <asm/opal.h> +#include <asm/io.h> +#include <asm/uaccess.h> + + +/** + * The msg member must be at the end of the struct, as it's followed by the + * message data. + */ +struct opal_prd_msg_queue_item { + struct list_head list; + struct opal_prd_msg_header msg; +}; + +static struct device_node *prd_node; +static LIST_HEAD(opal_prd_msg_queue); +static DEFINE_SPINLOCK(opal_prd_msg_queue_lock); +static DECLARE_WAIT_QUEUE_HEAD(opal_prd_msg_wait); +static atomic_t prd_usage; + +static bool opal_prd_range_is_valid(uint64_t addr, uint64_t size) +{ + struct device_node *parent, *node; + bool found; + + if (addr + size < addr) + return false; + + parent = of_find_node_by_path("/reserved-memory"); + if (!parent) + return false; + + found = false; + + for_each_child_of_node(parent, node) { + uint64_t range_addr, range_size, range_end; + const __be32 *addrp; + const char *label; + + addrp = of_get_address(node, 0, &range_size, NULL); + + range_addr = of_read_number(addrp, 2); + range_end = range_addr + range_size; + + label = of_get_property(node, "ibm,prd-label", NULL); + + /* PRD ranges need a label */ + if (!label) + continue; + + if (range_end <= range_addr) + continue; + + if (addr >= range_addr && addr + size <= range_end) { + found = true; + of_node_put(node); + break; + } + } + + of_node_put(parent); + return found; +} + +static int opal_prd_open(struct inode *inode, struct file *file) +{ + /* + * Prevent multiple (separate) processes from concurrent interactions + * with the FW PRD channel + */ + if (atomic_xchg(&prd_usage, 1) == 1) + return -EBUSY; + + return 0; +} + +/* + * opal_prd_mmap - maps firmware-provided ranges into userspace + * @file: file structure for the device + * @vma: VMA to map the registers into + */ + +static int opal_prd_mmap(struct file *file, struct vm_area_struct *vma) +{ + size_t addr, size; + pgprot_t page_prot; + int rc; + + pr_devel("opal_prd_mmap(0x%016lx, 0x%016lx, 0x%lx, 0x%lx)\n", + vma->vm_start, vma->vm_end, vma->vm_pgoff, + vma->vm_flags); + + addr = vma->vm_pgoff << PAGE_SHIFT; + size = vma->vm_end - vma->vm_start; + + /* ensure we're mapping within one of the allowable ranges */ + if (!opal_prd_range_is_valid(addr, size)) + return -EINVAL; + + page_prot = phys_mem_access_prot(file, vma->vm_pgoff, + size, vma->vm_page_prot); + + rc = remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, size, + page_prot); + + return rc; +} + +static bool opal_msg_queue_empty(void) +{ + unsigned long flags; + bool ret; + + spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); + ret = list_empty(&opal_prd_msg_queue); + spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); + + return ret; +} + +static unsigned int opal_prd_poll(struct file *file, + struct poll_table_struct *wait) +{ + poll_wait(file, &opal_prd_msg_wait, wait); + + if (!opal_msg_queue_empty()) + return POLLIN | POLLRDNORM; + + return 0; +} + +static ssize_t opal_prd_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct opal_prd_msg_queue_item *item; + unsigned long flags; + ssize_t size, err; + int rc; + + /* we need at least a header's worth of data */ + if (count < sizeof(item->msg)) + return -EINVAL; + + if (*ppos) + return -ESPIPE; + + item = NULL; + + for (;;) { + + spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); + if (!list_empty(&opal_prd_msg_queue)) { + item = list_first_entry(&opal_prd_msg_queue, + struct opal_prd_msg_queue_item, list); + list_del(&item->list); + } + spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); + + if (item) + break; + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + rc = wait_event_interruptible(opal_prd_msg_wait, + !opal_msg_queue_empty()); + if (rc) + return -EINTR; + } + + size = be16_to_cpu(item->msg.size); + if (size > count) { + err = -EINVAL; + goto err_requeue; + } + + rc = copy_to_user(buf, &item->msg, size); + if (rc) { + err = -EFAULT; + goto err_requeue; + } + + kfree(item); + + return size; + +err_requeue: + /* eep! re-queue at the head of the list */ + spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); + list_add(&item->list, &opal_prd_msg_queue); + spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); + return err; +} + +static ssize_t opal_prd_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct opal_prd_msg_header hdr; + ssize_t size; + void *msg; + int rc; + + size = sizeof(hdr); + + if (count < size) + return -EINVAL; + + /* grab the header */ + rc = copy_from_user(&hdr, buf, sizeof(hdr)); + if (rc) + return -EFAULT; + + size = be16_to_cpu(hdr.size); + + msg = kmalloc(size, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + rc = copy_from_user(msg, buf, size); + if (rc) { + size = -EFAULT; + goto out_free; + } + + rc = opal_prd_msg(msg); + if (rc) { + pr_warn("write: opal_prd_msg returned %d\n", rc); + size = -EIO; + } + +out_free: + kfree(msg); + + return size; +} + +static int opal_prd_release(struct inode *inode, struct file *file) +{ + struct opal_prd_msg_header msg; + + msg.size = cpu_to_be16(sizeof(msg)); + msg.type = OPAL_PRD_MSG_TYPE_FINI; + + opal_prd_msg((struct opal_prd_msg *)&msg); + + atomic_xchg(&prd_usage, 0); + + return 0; +} + +static long opal_prd_ioctl(struct file *file, unsigned int cmd, + unsigned long param) +{ + struct opal_prd_info info; + struct opal_prd_scom scom; + int rc = 0; + + switch (cmd) { + case OPAL_PRD_GET_INFO: + memset(&info, 0, sizeof(info)); + info.version = OPAL_PRD_KERNEL_VERSION; + rc = copy_to_user((void __user *)param, &info, sizeof(info)); + if (rc) + return -EFAULT; + break; + + case OPAL_PRD_SCOM_READ: + rc = copy_from_user(&scom, (void __user *)param, sizeof(scom)); + if (rc) + return -EFAULT; + + scom.rc = opal_xscom_read(scom.chip, scom.addr, + (__be64 *)&scom.data); + scom.data = be64_to_cpu(scom.data); + pr_devel("ioctl SCOM_READ: chip %llx addr %016llx data %016llx rc %lld\n", + scom.chip, scom.addr, scom.data, scom.rc); + + rc = copy_to_user((void __user *)param, &scom, sizeof(scom)); + if (rc) + return -EFAULT; + break; + + case OPAL_PRD_SCOM_WRITE: + rc = copy_from_user(&scom, (void __user *)param, sizeof(scom)); + if (rc) + return -EFAULT; + + scom.rc = opal_xscom_write(scom.chip, scom.addr, scom.data); + pr_devel("ioctl SCOM_WRITE: chip %llx addr %016llx data %016llx rc %lld\n", + scom.chip, scom.addr, scom.data, scom.rc); + + rc = copy_to_user((void __user *)param, &scom, sizeof(scom)); + if (rc) + return -EFAULT; + break; + + default: + rc = -EINVAL; + } + + return rc; +} + +static const struct file_operations opal_prd_fops = { + .open = opal_prd_open, + .mmap = opal_prd_mmap, + .poll = opal_prd_poll, + .read = opal_prd_read, + .write = opal_prd_write, + .unlocked_ioctl = opal_prd_ioctl, + .release = opal_prd_release, + .owner = THIS_MODULE, +}; + +static struct miscdevice opal_prd_dev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "opal-prd", + .fops = &opal_prd_fops, +}; + +/* opal interface */ +static int opal_prd_msg_notifier(struct notifier_block *nb, + unsigned long msg_type, void *_msg) +{ + struct opal_prd_msg_queue_item *item; + struct opal_prd_msg_header *hdr; + struct opal_msg *msg = _msg; + int msg_size, item_size; + unsigned long flags; + + if (msg_type != OPAL_MSG_PRD) + return 0; + + /* Calculate total size of the message and item we need to store. The + * 'size' field in the header includes the header itself. */ + hdr = (void *)msg->params; + msg_size = be16_to_cpu(hdr->size); + item_size = msg_size + sizeof(*item) - sizeof(item->msg); + + item = kzalloc(item_size, GFP_ATOMIC); + if (!item) + return -ENOMEM; + + memcpy(&item->msg, msg->params, msg_size); + + spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); + list_add_tail(&item->list, &opal_prd_msg_queue); + spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); + + wake_up_interruptible(&opal_prd_msg_wait); + + return 0; +} + +static struct notifier_block opal_prd_event_nb = { + .notifier_call = opal_prd_msg_notifier, + .next = NULL, + .priority = 0, +}; + +static int opal_prd_probe(struct platform_device *pdev) +{ + int rc; + + if (!pdev || !pdev->dev.of_node) + return -ENODEV; + + /* We should only have one prd driver instance per machine; ensure + * that we only get a valid probe on a single OF node. + */ + if (prd_node) + return -EBUSY; + + prd_node = pdev->dev.of_node; + + rc = opal_message_notifier_register(OPAL_MSG_PRD, &opal_prd_event_nb); + if (rc) { + pr_err("Couldn't register event notifier\n"); + return rc; + } + + rc = misc_register(&opal_prd_dev); + if (rc) { + pr_err("failed to register miscdev\n"); + opal_message_notifier_unregister(OPAL_MSG_PRD, + &opal_prd_event_nb); + return rc; + } + + return 0; +} + +static int opal_prd_remove(struct platform_device *pdev) +{ + misc_deregister(&opal_prd_dev); + opal_message_notifier_unregister(OPAL_MSG_PRD, &opal_prd_event_nb); + return 0; +} + +static const struct of_device_id opal_prd_match[] = { + { .compatible = "ibm,opal-prd" }, + { }, +}; + +static struct platform_driver opal_prd_driver = { + .driver = { + .name = "opal-prd", + .owner = THIS_MODULE, + .of_match_table = opal_prd_match, + }, + .probe = opal_prd_probe, + .remove = opal_prd_remove, +}; + +module_platform_driver(opal_prd_driver); + +MODULE_DEVICE_TABLE(of, opal_prd_match); +MODULE_DESCRIPTION("PowerNV OPAL runtime diagnostic driver"); +MODULE_LICENSE("GPL"); |