11802d0beSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 20d7cd855SJeremy Kerr /* 30d7cd855SJeremy Kerr * OPAL Runtime Diagnostics interface driver 40d7cd855SJeremy Kerr * Supported on POWERNV platform 50d7cd855SJeremy Kerr * 60d7cd855SJeremy Kerr * Copyright IBM Corporation 2015 70d7cd855SJeremy Kerr */ 80d7cd855SJeremy Kerr 90d7cd855SJeremy Kerr #define pr_fmt(fmt) "opal-prd: " fmt 100d7cd855SJeremy Kerr 110d7cd855SJeremy Kerr #include <linux/kernel.h> 120d7cd855SJeremy Kerr #include <linux/module.h> 130d7cd855SJeremy Kerr #include <linux/platform_device.h> 140d7cd855SJeremy Kerr #include <linux/miscdevice.h> 150d7cd855SJeremy Kerr #include <linux/fs.h> 160d7cd855SJeremy Kerr #include <linux/of.h> 170d7cd855SJeremy Kerr #include <linux/of_address.h> 180d7cd855SJeremy Kerr #include <linux/poll.h> 190d7cd855SJeremy Kerr #include <linux/mm.h> 200d7cd855SJeremy Kerr #include <linux/slab.h> 210d7cd855SJeremy Kerr #include <asm/opal-prd.h> 220d7cd855SJeremy Kerr #include <asm/opal.h> 230d7cd855SJeremy Kerr #include <asm/io.h> 247c0f6ba6SLinus Torvalds #include <linux/uaccess.h> 250d7cd855SJeremy Kerr 260d7cd855SJeremy Kerr 27*feea65a3SMichael Ellerman struct opal_prd_msg { 28*feea65a3SMichael Ellerman union { 29*feea65a3SMichael Ellerman struct opal_prd_msg_header header; 30*feea65a3SMichael Ellerman DECLARE_FLEX_ARRAY(u8, data); 31*feea65a3SMichael Ellerman }; 32*feea65a3SMichael Ellerman }; 33*feea65a3SMichael Ellerman 34fb248c31SOliver O'Halloran /* 357185795aSJeremy Kerr * The msg member must be at the end of the struct, as it's followed by the 367185795aSJeremy Kerr * message data. 377185795aSJeremy Kerr */ 380d7cd855SJeremy Kerr struct opal_prd_msg_queue_item { 390d7cd855SJeremy Kerr struct list_head list; 40*feea65a3SMichael Ellerman struct opal_prd_msg msg; 410d7cd855SJeremy Kerr }; 420d7cd855SJeremy Kerr 430d7cd855SJeremy Kerr static struct device_node *prd_node; 440d7cd855SJeremy Kerr static LIST_HEAD(opal_prd_msg_queue); 450d7cd855SJeremy Kerr static DEFINE_SPINLOCK(opal_prd_msg_queue_lock); 460d7cd855SJeremy Kerr static DECLARE_WAIT_QUEUE_HEAD(opal_prd_msg_wait); 470d7cd855SJeremy Kerr static atomic_t prd_usage; 480d7cd855SJeremy Kerr 490d7cd855SJeremy Kerr static bool opal_prd_range_is_valid(uint64_t addr, uint64_t size) 500d7cd855SJeremy Kerr { 510d7cd855SJeremy Kerr struct device_node *parent, *node; 520d7cd855SJeremy Kerr bool found; 530d7cd855SJeremy Kerr 540d7cd855SJeremy Kerr if (addr + size < addr) 550d7cd855SJeremy Kerr return false; 560d7cd855SJeremy Kerr 570d7cd855SJeremy Kerr parent = of_find_node_by_path("/reserved-memory"); 580d7cd855SJeremy Kerr if (!parent) 590d7cd855SJeremy Kerr return false; 600d7cd855SJeremy Kerr 610d7cd855SJeremy Kerr found = false; 620d7cd855SJeremy Kerr 630d7cd855SJeremy Kerr for_each_child_of_node(parent, node) { 640d7cd855SJeremy Kerr uint64_t range_addr, range_size, range_end; 650d7cd855SJeremy Kerr const __be32 *addrp; 660d7cd855SJeremy Kerr const char *label; 670d7cd855SJeremy Kerr 680d7cd855SJeremy Kerr addrp = of_get_address(node, 0, &range_size, NULL); 690d7cd855SJeremy Kerr 700d7cd855SJeremy Kerr range_addr = of_read_number(addrp, 2); 710d7cd855SJeremy Kerr range_end = range_addr + range_size; 720d7cd855SJeremy Kerr 730d7cd855SJeremy Kerr label = of_get_property(node, "ibm,prd-label", NULL); 740d7cd855SJeremy Kerr 750d7cd855SJeremy Kerr /* PRD ranges need a label */ 760d7cd855SJeremy Kerr if (!label) 770d7cd855SJeremy Kerr continue; 780d7cd855SJeremy Kerr 790d7cd855SJeremy Kerr if (range_end <= range_addr) 800d7cd855SJeremy Kerr continue; 810d7cd855SJeremy Kerr 820d7cd855SJeremy Kerr if (addr >= range_addr && addr + size <= range_end) { 830d7cd855SJeremy Kerr found = true; 840d7cd855SJeremy Kerr of_node_put(node); 850d7cd855SJeremy Kerr break; 860d7cd855SJeremy Kerr } 870d7cd855SJeremy Kerr } 880d7cd855SJeremy Kerr 890d7cd855SJeremy Kerr of_node_put(parent); 900d7cd855SJeremy Kerr return found; 910d7cd855SJeremy Kerr } 920d7cd855SJeremy Kerr 930d7cd855SJeremy Kerr static int opal_prd_open(struct inode *inode, struct file *file) 940d7cd855SJeremy Kerr { 950d7cd855SJeremy Kerr /* 960d7cd855SJeremy Kerr * Prevent multiple (separate) processes from concurrent interactions 970d7cd855SJeremy Kerr * with the FW PRD channel 980d7cd855SJeremy Kerr */ 990d7cd855SJeremy Kerr if (atomic_xchg(&prd_usage, 1) == 1) 1000d7cd855SJeremy Kerr return -EBUSY; 1010d7cd855SJeremy Kerr 1020d7cd855SJeremy Kerr return 0; 1030d7cd855SJeremy Kerr } 1040d7cd855SJeremy Kerr 1050d7cd855SJeremy Kerr /* 1060d7cd855SJeremy Kerr * opal_prd_mmap - maps firmware-provided ranges into userspace 1070d7cd855SJeremy Kerr * @file: file structure for the device 1080d7cd855SJeremy Kerr * @vma: VMA to map the registers into 1090d7cd855SJeremy Kerr */ 1100d7cd855SJeremy Kerr 1110d7cd855SJeremy Kerr static int opal_prd_mmap(struct file *file, struct vm_area_struct *vma) 1120d7cd855SJeremy Kerr { 1130d7cd855SJeremy Kerr size_t addr, size; 114d8ea782bSVaidyanathan Srinivasan pgprot_t page_prot; 1150d7cd855SJeremy Kerr 1160d7cd855SJeremy Kerr pr_devel("opal_prd_mmap(0x%016lx, 0x%016lx, 0x%lx, 0x%lx)\n", 1170d7cd855SJeremy Kerr vma->vm_start, vma->vm_end, vma->vm_pgoff, 1180d7cd855SJeremy Kerr vma->vm_flags); 1190d7cd855SJeremy Kerr 1200d7cd855SJeremy Kerr addr = vma->vm_pgoff << PAGE_SHIFT; 1210d7cd855SJeremy Kerr size = vma->vm_end - vma->vm_start; 1220d7cd855SJeremy Kerr 1230d7cd855SJeremy Kerr /* ensure we're mapping within one of the allowable ranges */ 1240d7cd855SJeremy Kerr if (!opal_prd_range_is_valid(addr, size)) 1250d7cd855SJeremy Kerr return -EINVAL; 1260d7cd855SJeremy Kerr 127d8ea782bSVaidyanathan Srinivasan page_prot = phys_mem_access_prot(file, vma->vm_pgoff, 128d8ea782bSVaidyanathan Srinivasan size, vma->vm_page_prot); 1290d7cd855SJeremy Kerr 13069931cc3Sdingsenjie return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, size, 131d8ea782bSVaidyanathan Srinivasan page_prot); 1320d7cd855SJeremy Kerr } 1330d7cd855SJeremy Kerr 1340d7cd855SJeremy Kerr static bool opal_msg_queue_empty(void) 1350d7cd855SJeremy Kerr { 1360d7cd855SJeremy Kerr unsigned long flags; 1370d7cd855SJeremy Kerr bool ret; 1380d7cd855SJeremy Kerr 1390d7cd855SJeremy Kerr spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); 1400d7cd855SJeremy Kerr ret = list_empty(&opal_prd_msg_queue); 1410d7cd855SJeremy Kerr spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); 1420d7cd855SJeremy Kerr 1430d7cd855SJeremy Kerr return ret; 1440d7cd855SJeremy Kerr } 1450d7cd855SJeremy Kerr 1468153a5eaSAl Viro static __poll_t opal_prd_poll(struct file *file, 1470d7cd855SJeremy Kerr struct poll_table_struct *wait) 1480d7cd855SJeremy Kerr { 1490d7cd855SJeremy Kerr poll_wait(file, &opal_prd_msg_wait, wait); 1500d7cd855SJeremy Kerr 1510d7cd855SJeremy Kerr if (!opal_msg_queue_empty()) 152a9a08845SLinus Torvalds return EPOLLIN | EPOLLRDNORM; 1530d7cd855SJeremy Kerr 1540d7cd855SJeremy Kerr return 0; 1550d7cd855SJeremy Kerr } 1560d7cd855SJeremy Kerr 1570d7cd855SJeremy Kerr static ssize_t opal_prd_read(struct file *file, char __user *buf, 1580d7cd855SJeremy Kerr size_t count, loff_t *ppos) 1590d7cd855SJeremy Kerr { 1600d7cd855SJeremy Kerr struct opal_prd_msg_queue_item *item; 1610d7cd855SJeremy Kerr unsigned long flags; 1620d7cd855SJeremy Kerr ssize_t size, err; 1630d7cd855SJeremy Kerr int rc; 1640d7cd855SJeremy Kerr 1650d7cd855SJeremy Kerr /* we need at least a header's worth of data */ 166*feea65a3SMichael Ellerman if (count < sizeof(item->msg.header)) 1670d7cd855SJeremy Kerr return -EINVAL; 1680d7cd855SJeremy Kerr 1690d7cd855SJeremy Kerr if (*ppos) 1700d7cd855SJeremy Kerr return -ESPIPE; 1710d7cd855SJeremy Kerr 1720d7cd855SJeremy Kerr item = NULL; 1730d7cd855SJeremy Kerr 1740d7cd855SJeremy Kerr for (;;) { 1750d7cd855SJeremy Kerr 1760d7cd855SJeremy Kerr spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); 1770d7cd855SJeremy Kerr if (!list_empty(&opal_prd_msg_queue)) { 1780d7cd855SJeremy Kerr item = list_first_entry(&opal_prd_msg_queue, 1790d7cd855SJeremy Kerr struct opal_prd_msg_queue_item, list); 1800d7cd855SJeremy Kerr list_del(&item->list); 1810d7cd855SJeremy Kerr } 1820d7cd855SJeremy Kerr spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); 1830d7cd855SJeremy Kerr 1840d7cd855SJeremy Kerr if (item) 1850d7cd855SJeremy Kerr break; 1860d7cd855SJeremy Kerr 1870d7cd855SJeremy Kerr if (file->f_flags & O_NONBLOCK) 1880d7cd855SJeremy Kerr return -EAGAIN; 1890d7cd855SJeremy Kerr 1900d7cd855SJeremy Kerr rc = wait_event_interruptible(opal_prd_msg_wait, 1910d7cd855SJeremy Kerr !opal_msg_queue_empty()); 1920d7cd855SJeremy Kerr if (rc) 1930d7cd855SJeremy Kerr return -EINTR; 1940d7cd855SJeremy Kerr } 1950d7cd855SJeremy Kerr 196*feea65a3SMichael Ellerman size = be16_to_cpu(item->msg.header.size); 1970d7cd855SJeremy Kerr if (size > count) { 1980d7cd855SJeremy Kerr err = -EINVAL; 1990d7cd855SJeremy Kerr goto err_requeue; 2000d7cd855SJeremy Kerr } 2010d7cd855SJeremy Kerr 2020d7cd855SJeremy Kerr rc = copy_to_user(buf, &item->msg, size); 2030d7cd855SJeremy Kerr if (rc) { 2040d7cd855SJeremy Kerr err = -EFAULT; 2050d7cd855SJeremy Kerr goto err_requeue; 2060d7cd855SJeremy Kerr } 2070d7cd855SJeremy Kerr 2080d7cd855SJeremy Kerr kfree(item); 2090d7cd855SJeremy Kerr 2100d7cd855SJeremy Kerr return size; 2110d7cd855SJeremy Kerr 2120d7cd855SJeremy Kerr err_requeue: 2130d7cd855SJeremy Kerr /* eep! re-queue at the head of the list */ 2140d7cd855SJeremy Kerr spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); 2150d7cd855SJeremy Kerr list_add(&item->list, &opal_prd_msg_queue); 2160d7cd855SJeremy Kerr spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); 2170d7cd855SJeremy Kerr return err; 2180d7cd855SJeremy Kerr } 2190d7cd855SJeremy Kerr 2200d7cd855SJeremy Kerr static ssize_t opal_prd_write(struct file *file, const char __user *buf, 2210d7cd855SJeremy Kerr size_t count, loff_t *ppos) 2220d7cd855SJeremy Kerr { 2230d7cd855SJeremy Kerr struct opal_prd_msg_header hdr; 2240d7cd855SJeremy Kerr ssize_t size; 2250d7cd855SJeremy Kerr void *msg; 2260d7cd855SJeremy Kerr int rc; 2270d7cd855SJeremy Kerr 2280d7cd855SJeremy Kerr size = sizeof(hdr); 2290d7cd855SJeremy Kerr 2300d7cd855SJeremy Kerr if (count < size) 2310d7cd855SJeremy Kerr return -EINVAL; 2320d7cd855SJeremy Kerr 2330d7cd855SJeremy Kerr /* grab the header */ 2340d7cd855SJeremy Kerr rc = copy_from_user(&hdr, buf, sizeof(hdr)); 2350d7cd855SJeremy Kerr if (rc) 2360d7cd855SJeremy Kerr return -EFAULT; 2370d7cd855SJeremy Kerr 2380d7cd855SJeremy Kerr size = be16_to_cpu(hdr.size); 2390d7cd855SJeremy Kerr 2405588b29aSGeliang Tang msg = memdup_user(buf, size); 2415588b29aSGeliang Tang if (IS_ERR(msg)) 2425588b29aSGeliang Tang return PTR_ERR(msg); 2430d7cd855SJeremy Kerr 2440d7cd855SJeremy Kerr rc = opal_prd_msg(msg); 2450d7cd855SJeremy Kerr if (rc) { 2460d7cd855SJeremy Kerr pr_warn("write: opal_prd_msg returned %d\n", rc); 2470d7cd855SJeremy Kerr size = -EIO; 2480d7cd855SJeremy Kerr } 2490d7cd855SJeremy Kerr 2500d7cd855SJeremy Kerr kfree(msg); 2510d7cd855SJeremy Kerr 2520d7cd855SJeremy Kerr return size; 2530d7cd855SJeremy Kerr } 2540d7cd855SJeremy Kerr 2550d7cd855SJeremy Kerr static int opal_prd_release(struct inode *inode, struct file *file) 2560d7cd855SJeremy Kerr { 2570d7cd855SJeremy Kerr struct opal_prd_msg_header msg; 2580d7cd855SJeremy Kerr 2590d7cd855SJeremy Kerr msg.size = cpu_to_be16(sizeof(msg)); 2600d7cd855SJeremy Kerr msg.type = OPAL_PRD_MSG_TYPE_FINI; 2610d7cd855SJeremy Kerr 2620d7cd855SJeremy Kerr opal_prd_msg((struct opal_prd_msg *)&msg); 2630d7cd855SJeremy Kerr 2640d7cd855SJeremy Kerr atomic_xchg(&prd_usage, 0); 2650d7cd855SJeremy Kerr 2660d7cd855SJeremy Kerr return 0; 2670d7cd855SJeremy Kerr } 2680d7cd855SJeremy Kerr 2690d7cd855SJeremy Kerr static long opal_prd_ioctl(struct file *file, unsigned int cmd, 2700d7cd855SJeremy Kerr unsigned long param) 2710d7cd855SJeremy Kerr { 2720d7cd855SJeremy Kerr struct opal_prd_info info; 2730d7cd855SJeremy Kerr struct opal_prd_scom scom; 2740d7cd855SJeremy Kerr int rc = 0; 2750d7cd855SJeremy Kerr 2760d7cd855SJeremy Kerr switch (cmd) { 2770d7cd855SJeremy Kerr case OPAL_PRD_GET_INFO: 2780d7cd855SJeremy Kerr memset(&info, 0, sizeof(info)); 2790d7cd855SJeremy Kerr info.version = OPAL_PRD_KERNEL_VERSION; 2800d7cd855SJeremy Kerr rc = copy_to_user((void __user *)param, &info, sizeof(info)); 2810d7cd855SJeremy Kerr if (rc) 2820d7cd855SJeremy Kerr return -EFAULT; 2830d7cd855SJeremy Kerr break; 2840d7cd855SJeremy Kerr 2850d7cd855SJeremy Kerr case OPAL_PRD_SCOM_READ: 2860d7cd855SJeremy Kerr rc = copy_from_user(&scom, (void __user *)param, sizeof(scom)); 2870d7cd855SJeremy Kerr if (rc) 2880d7cd855SJeremy Kerr return -EFAULT; 2890d7cd855SJeremy Kerr 2900d7cd855SJeremy Kerr scom.rc = opal_xscom_read(scom.chip, scom.addr, 2910d7cd855SJeremy Kerr (__be64 *)&scom.data); 2920d7cd855SJeremy Kerr scom.data = be64_to_cpu(scom.data); 2930d7cd855SJeremy Kerr pr_devel("ioctl SCOM_READ: chip %llx addr %016llx data %016llx rc %lld\n", 2940d7cd855SJeremy Kerr scom.chip, scom.addr, scom.data, scom.rc); 2950d7cd855SJeremy Kerr 2960d7cd855SJeremy Kerr rc = copy_to_user((void __user *)param, &scom, sizeof(scom)); 2970d7cd855SJeremy Kerr if (rc) 2980d7cd855SJeremy Kerr return -EFAULT; 2990d7cd855SJeremy Kerr break; 3000d7cd855SJeremy Kerr 3010d7cd855SJeremy Kerr case OPAL_PRD_SCOM_WRITE: 3020d7cd855SJeremy Kerr rc = copy_from_user(&scom, (void __user *)param, sizeof(scom)); 3030d7cd855SJeremy Kerr if (rc) 3040d7cd855SJeremy Kerr return -EFAULT; 3050d7cd855SJeremy Kerr 3060d7cd855SJeremy Kerr scom.rc = opal_xscom_write(scom.chip, scom.addr, scom.data); 3070d7cd855SJeremy Kerr pr_devel("ioctl SCOM_WRITE: chip %llx addr %016llx data %016llx rc %lld\n", 3080d7cd855SJeremy Kerr scom.chip, scom.addr, scom.data, scom.rc); 3090d7cd855SJeremy Kerr 3100d7cd855SJeremy Kerr rc = copy_to_user((void __user *)param, &scom, sizeof(scom)); 3110d7cd855SJeremy Kerr if (rc) 3120d7cd855SJeremy Kerr return -EFAULT; 3130d7cd855SJeremy Kerr break; 3140d7cd855SJeremy Kerr 3150d7cd855SJeremy Kerr default: 3160d7cd855SJeremy Kerr rc = -EINVAL; 3170d7cd855SJeremy Kerr } 3180d7cd855SJeremy Kerr 3190d7cd855SJeremy Kerr return rc; 3200d7cd855SJeremy Kerr } 3210d7cd855SJeremy Kerr 3220d7cd855SJeremy Kerr static const struct file_operations opal_prd_fops = { 3230d7cd855SJeremy Kerr .open = opal_prd_open, 3240d7cd855SJeremy Kerr .mmap = opal_prd_mmap, 3250d7cd855SJeremy Kerr .poll = opal_prd_poll, 3260d7cd855SJeremy Kerr .read = opal_prd_read, 3270d7cd855SJeremy Kerr .write = opal_prd_write, 3280d7cd855SJeremy Kerr .unlocked_ioctl = opal_prd_ioctl, 3290d7cd855SJeremy Kerr .release = opal_prd_release, 3300d7cd855SJeremy Kerr .owner = THIS_MODULE, 3310d7cd855SJeremy Kerr }; 3320d7cd855SJeremy Kerr 3330d7cd855SJeremy Kerr static struct miscdevice opal_prd_dev = { 3340d7cd855SJeremy Kerr .minor = MISC_DYNAMIC_MINOR, 3350d7cd855SJeremy Kerr .name = "opal-prd", 3360d7cd855SJeremy Kerr .fops = &opal_prd_fops, 3370d7cd855SJeremy Kerr }; 3380d7cd855SJeremy Kerr 3390d7cd855SJeremy Kerr /* opal interface */ 3400d7cd855SJeremy Kerr static int opal_prd_msg_notifier(struct notifier_block *nb, 3410d7cd855SJeremy Kerr unsigned long msg_type, void *_msg) 3420d7cd855SJeremy Kerr { 3430d7cd855SJeremy Kerr struct opal_prd_msg_queue_item *item; 3440d7cd855SJeremy Kerr struct opal_prd_msg_header *hdr; 3450d7cd855SJeremy Kerr struct opal_msg *msg = _msg; 3467185795aSJeremy Kerr int msg_size, item_size; 3470d7cd855SJeremy Kerr unsigned long flags; 3480d7cd855SJeremy Kerr 349587164cdSVasant Hegde if (msg_type != OPAL_MSG_PRD && msg_type != OPAL_MSG_PRD2) 3500d7cd855SJeremy Kerr return 0; 3510d7cd855SJeremy Kerr 3527185795aSJeremy Kerr /* Calculate total size of the message and item we need to store. The 3537185795aSJeremy Kerr * 'size' field in the header includes the header itself. */ 3540d7cd855SJeremy Kerr hdr = (void *)msg->params; 3557185795aSJeremy Kerr msg_size = be16_to_cpu(hdr->size); 3567185795aSJeremy Kerr item_size = msg_size + sizeof(*item) - sizeof(item->msg); 3570d7cd855SJeremy Kerr 3587185795aSJeremy Kerr item = kzalloc(item_size, GFP_ATOMIC); 3590d7cd855SJeremy Kerr if (!item) 3600d7cd855SJeremy Kerr return -ENOMEM; 3610d7cd855SJeremy Kerr 362*feea65a3SMichael Ellerman memcpy(&item->msg.data, msg->params, msg_size); 3630d7cd855SJeremy Kerr 3640d7cd855SJeremy Kerr spin_lock_irqsave(&opal_prd_msg_queue_lock, flags); 3650d7cd855SJeremy Kerr list_add_tail(&item->list, &opal_prd_msg_queue); 3660d7cd855SJeremy Kerr spin_unlock_irqrestore(&opal_prd_msg_queue_lock, flags); 3670d7cd855SJeremy Kerr 3680d7cd855SJeremy Kerr wake_up_interruptible(&opal_prd_msg_wait); 3690d7cd855SJeremy Kerr 3700d7cd855SJeremy Kerr return 0; 3710d7cd855SJeremy Kerr } 3720d7cd855SJeremy Kerr 3730d7cd855SJeremy Kerr static struct notifier_block opal_prd_event_nb = { 3740d7cd855SJeremy Kerr .notifier_call = opal_prd_msg_notifier, 3750d7cd855SJeremy Kerr .next = NULL, 3760d7cd855SJeremy Kerr .priority = 0, 3770d7cd855SJeremy Kerr }; 3780d7cd855SJeremy Kerr 37952862ab3SVasant Hegde static struct notifier_block opal_prd_event_nb2 = { 38052862ab3SVasant Hegde .notifier_call = opal_prd_msg_notifier, 38152862ab3SVasant Hegde .next = NULL, 38252862ab3SVasant Hegde .priority = 0, 38352862ab3SVasant Hegde }; 38452862ab3SVasant Hegde 3850d7cd855SJeremy Kerr static int opal_prd_probe(struct platform_device *pdev) 3860d7cd855SJeremy Kerr { 3870d7cd855SJeremy Kerr int rc; 3880d7cd855SJeremy Kerr 3890d7cd855SJeremy Kerr if (!pdev || !pdev->dev.of_node) 3900d7cd855SJeremy Kerr return -ENODEV; 3910d7cd855SJeremy Kerr 3920d7cd855SJeremy Kerr /* We should only have one prd driver instance per machine; ensure 3930d7cd855SJeremy Kerr * that we only get a valid probe on a single OF node. 3940d7cd855SJeremy Kerr */ 3950d7cd855SJeremy Kerr if (prd_node) 3960d7cd855SJeremy Kerr return -EBUSY; 3970d7cd855SJeremy Kerr 3980d7cd855SJeremy Kerr prd_node = pdev->dev.of_node; 3990d7cd855SJeremy Kerr 4000d7cd855SJeremy Kerr rc = opal_message_notifier_register(OPAL_MSG_PRD, &opal_prd_event_nb); 4010d7cd855SJeremy Kerr if (rc) { 4020d7cd855SJeremy Kerr pr_err("Couldn't register event notifier\n"); 4030d7cd855SJeremy Kerr return rc; 4040d7cd855SJeremy Kerr } 4050d7cd855SJeremy Kerr 40652862ab3SVasant Hegde rc = opal_message_notifier_register(OPAL_MSG_PRD2, &opal_prd_event_nb2); 407587164cdSVasant Hegde if (rc) { 408587164cdSVasant Hegde pr_err("Couldn't register PRD2 event notifier\n"); 40952862ab3SVasant Hegde opal_message_notifier_unregister(OPAL_MSG_PRD, &opal_prd_event_nb); 410587164cdSVasant Hegde return rc; 411587164cdSVasant Hegde } 412587164cdSVasant Hegde 4130d7cd855SJeremy Kerr rc = misc_register(&opal_prd_dev); 4140d7cd855SJeremy Kerr if (rc) { 4150d7cd855SJeremy Kerr pr_err("failed to register miscdev\n"); 4160d7cd855SJeremy Kerr opal_message_notifier_unregister(OPAL_MSG_PRD, 4170d7cd855SJeremy Kerr &opal_prd_event_nb); 41852862ab3SVasant Hegde opal_message_notifier_unregister(OPAL_MSG_PRD2, 41952862ab3SVasant Hegde &opal_prd_event_nb2); 4200d7cd855SJeremy Kerr return rc; 4210d7cd855SJeremy Kerr } 4220d7cd855SJeremy Kerr 4230d7cd855SJeremy Kerr return 0; 4240d7cd855SJeremy Kerr } 4250d7cd855SJeremy Kerr 4260d7cd855SJeremy Kerr static int opal_prd_remove(struct platform_device *pdev) 4270d7cd855SJeremy Kerr { 4280d7cd855SJeremy Kerr misc_deregister(&opal_prd_dev); 4290d7cd855SJeremy Kerr opal_message_notifier_unregister(OPAL_MSG_PRD, &opal_prd_event_nb); 43052862ab3SVasant Hegde opal_message_notifier_unregister(OPAL_MSG_PRD2, &opal_prd_event_nb2); 4310d7cd855SJeremy Kerr return 0; 4320d7cd855SJeremy Kerr } 4330d7cd855SJeremy Kerr 4340d7cd855SJeremy Kerr static const struct of_device_id opal_prd_match[] = { 4350d7cd855SJeremy Kerr { .compatible = "ibm,opal-prd" }, 4360d7cd855SJeremy Kerr { }, 4370d7cd855SJeremy Kerr }; 4380d7cd855SJeremy Kerr 4390d7cd855SJeremy Kerr static struct platform_driver opal_prd_driver = { 4400d7cd855SJeremy Kerr .driver = { 4410d7cd855SJeremy Kerr .name = "opal-prd", 4420d7cd855SJeremy Kerr .of_match_table = opal_prd_match, 4430d7cd855SJeremy Kerr }, 4440d7cd855SJeremy Kerr .probe = opal_prd_probe, 4450d7cd855SJeremy Kerr .remove = opal_prd_remove, 4460d7cd855SJeremy Kerr }; 4470d7cd855SJeremy Kerr 4480d7cd855SJeremy Kerr module_platform_driver(opal_prd_driver); 4490d7cd855SJeremy Kerr 4500d7cd855SJeremy Kerr MODULE_DEVICE_TABLE(of, opal_prd_match); 4510d7cd855SJeremy Kerr MODULE_DESCRIPTION("PowerNV OPAL runtime diagnostic driver"); 4520d7cd855SJeremy Kerr MODULE_LICENSE("GPL"); 453