diff options
author | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-09-22 19:54:53 (GMT) |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-09-22 20:01:40 (GMT) |
commit | ae19ffbadc1b2100285a5b5b3d0a4e0a11390904 (patch) | |
tree | 3c2086ab67398a019089a47ca3f362a4bc6db74f /drivers/staging/vme/devices/vme_user.c | |
parent | 34e84f39a27d059a3e6ec6e8b94aafa702e6f220 (diff) | |
parent | 9173a8ef24a6b1b8031507b35b8ffe5f85a87692 (diff) | |
download | linux-fsl-qoriq-ae19ffbadc1b2100285a5b5b3d0a4e0a11390904.tar.xz |
Merge branch 'master' into for-linus
Diffstat (limited to 'drivers/staging/vme/devices/vme_user.c')
-rw-r--r-- | drivers/staging/vme/devices/vme_user.c | 826 |
1 files changed, 826 insertions, 0 deletions
diff --git a/drivers/staging/vme/devices/vme_user.c b/drivers/staging/vme/devices/vme_user.c new file mode 100644 index 0000000..7891288 --- /dev/null +++ b/drivers/staging/vme/devices/vme_user.c @@ -0,0 +1,826 @@ +/* + * VMEbus User access driver + * + * Author: Martyn Welch <martyn.welch@gefanuc.com> + * Copyright 2008 GE Fanuc Intelligent Platforms Embedded Systems, Inc. + * + * Based on work by: + * Tom Armistead and Ajit Prem + * Copyright 2004 Motorola Inc. + * + * + * 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. + */ + +#include <linux/cdev.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/ioctl.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/pagemap.h> +#include <linux/pci.h> +#include <linux/semaphore.h> +#include <linux/spinlock.h> +#include <linux/syscalls.h> +#include <linux/types.h> +#include <linux/version.h> + +#include <asm/io.h> +#include <asm/uaccess.h> + +#include "../vme.h" +#include "vme_user.h" + +static char driver_name[] = "vme_user"; + +static int bus[USER_BUS_MAX]; +static int bus_num; + +/* Currently Documentation/devices.txt defines the following for VME: + * + * 221 char VME bus + * 0 = /dev/bus/vme/m0 First master image + * 1 = /dev/bus/vme/m1 Second master image + * 2 = /dev/bus/vme/m2 Third master image + * 3 = /dev/bus/vme/m3 Fourth master image + * 4 = /dev/bus/vme/s0 First slave image + * 5 = /dev/bus/vme/s1 Second slave image + * 6 = /dev/bus/vme/s2 Third slave image + * 7 = /dev/bus/vme/s3 Fourth slave image + * 8 = /dev/bus/vme/ctl Control + * + * It is expected that all VME bus drivers will use the + * same interface. For interface documentation see + * http://www.vmelinux.org/. + * + * However the VME driver at http://www.vmelinux.org/ is rather old and doesn't + * even support the tsi148 chipset (which has 8 master and 8 slave windows). + * We'll run with this or now as far as possible, however it probably makes + * sense to get rid of the old mappings and just do everything dynamically. + * + * So for now, we'll restrict the driver to providing 4 masters and 4 slaves as + * defined above and try to support at least some of the interface from + * http://www.vmelinux.org/ as an alternative drive can be written providing a + * saner interface later. + * + * The vmelinux.org driver never supported slave images, the devices reserved + * for slaves were repurposed to support all 8 master images on the UniverseII! + * We shall support 4 masters and 4 slaves with this driver. + */ +#define VME_MAJOR 221 /* VME Major Device Number */ +#define VME_DEVS 9 /* Number of dev entries */ + +#define MASTER_MINOR 0 +#define MASTER_MAX 3 +#define SLAVE_MINOR 4 +#define SLAVE_MAX 7 +#define CONTROL_MINOR 8 + +#define PCI_BUF_SIZE 0x20000 /* Size of one slave image buffer */ + +/* + * Structure to handle image related parameters. + */ +typedef struct { + void __iomem *kern_buf; /* Buffer address in kernel space */ + dma_addr_t pci_buf; /* Buffer address in PCI address space */ + unsigned long long size_buf; /* Buffer size */ + struct semaphore sem; /* Semaphore for locking image */ + struct device *device; /* Sysfs device */ + struct vme_resource *resource; /* VME resource */ + int users; /* Number of current users */ +} image_desc_t; +static image_desc_t image[VME_DEVS]; + +typedef struct { + unsigned long reads; + unsigned long writes; + unsigned long ioctls; + unsigned long irqs; + unsigned long berrs; + unsigned long dmaErrors; + unsigned long timeouts; + unsigned long external; +} driver_stats_t; +static driver_stats_t statistics; + +struct cdev *vme_user_cdev; /* Character device */ +struct class *vme_user_sysfs_class; /* Sysfs class */ +struct device *vme_user_bridge; /* Pointer to the bridge device */ + + +static const int type[VME_DEVS] = { MASTER_MINOR, MASTER_MINOR, + MASTER_MINOR, MASTER_MINOR, + SLAVE_MINOR, SLAVE_MINOR, + SLAVE_MINOR, SLAVE_MINOR, + CONTROL_MINOR + }; + + +static int vme_user_open(struct inode *, struct file *); +static int vme_user_release(struct inode *, struct file *); +static ssize_t vme_user_read(struct file *, char *, size_t, loff_t *); +static ssize_t vme_user_write(struct file *, const char *, size_t, loff_t *); +static loff_t vme_user_llseek(struct file *, loff_t, int); +static int vme_user_ioctl(struct inode *, struct file *, unsigned int, + unsigned long); + +static int __init vme_user_probe(struct device *, int, int); +static int __exit vme_user_remove(struct device *, int, int); + +static struct file_operations vme_user_fops = { + .open = vme_user_open, + .release = vme_user_release, + .read = vme_user_read, + .write = vme_user_write, + .llseek = vme_user_llseek, + .ioctl = vme_user_ioctl, +}; + + +/* + * Reset all the statistic counters + */ +static void reset_counters(void) +{ + statistics.reads = 0; + statistics.writes = 0; + statistics.ioctls = 0; + statistics.irqs = 0; + statistics.berrs = 0; + statistics.dmaErrors = 0; + statistics.timeouts = 0; +} + +static int vme_user_open(struct inode *inode, struct file *file) +{ + int err; + unsigned int minor = MINOR(inode->i_rdev); + + down(&image[minor].sem); + /* Only allow device to be opened if a resource is allocated */ + if (image[minor].resource == NULL) { + printk(KERN_ERR "No resources allocated for device\n"); + err = -EINVAL; + goto err_res; + } + + /* Increment user count */ + image[minor].users++; + + up(&image[minor].sem); + + return 0; + +err_res: + up(&image[minor].sem); + + return err; +} + +static int vme_user_release(struct inode *inode, struct file *file) +{ + unsigned int minor = MINOR(inode->i_rdev); + + down(&image[minor].sem); + + /* Decrement user count */ + image[minor].users--; + + up(&image[minor].sem); + + return 0; +} + +/* + * We are going ot alloc a page during init per window for small transfers. + * Small transfers will go VME -> buffer -> user space. Larger (more than a + * page) transfers will lock the user space buffer into memory and then + * transfer the data directly into the user space buffers. + */ +static ssize_t resource_to_user(int minor, char __user *buf, size_t count, + loff_t *ppos) +{ + ssize_t retval; + ssize_t copied = 0; + + if (count <= image[minor].size_buf) { + /* We copy to kernel buffer */ + copied = vme_master_read(image[minor].resource, + image[minor].kern_buf, count, *ppos); + if (copied < 0) { + return (int)copied; + } + + retval = __copy_to_user(buf, image[minor].kern_buf, + (unsigned long)copied); + if (retval != 0) { + copied = (copied - retval); + printk("User copy failed\n"); + return -EINVAL; + } + + } else { + /* XXX Need to write this */ + printk("Currently don't support large transfers\n"); + /* Map in pages from userspace */ + + /* Call vme_master_read to do the transfer */ + return -EINVAL; + } + + return copied; +} + +/* + * We are going ot alloc a page during init per window for small transfers. + * Small transfers will go user space -> buffer -> VME. Larger (more than a + * page) transfers will lock the user space buffer into memory and then + * transfer the data directly from the user space buffers out to VME. + */ +static ssize_t resource_from_user(unsigned int minor, const char *buf, + size_t count, loff_t *ppos) +{ + ssize_t retval; + ssize_t copied = 0; + + if (count <= image[minor].size_buf) { + retval = __copy_from_user(image[minor].kern_buf, buf, + (unsigned long)count); + if (retval != 0) + copied = (copied - retval); + else + copied = count; + + copied = vme_master_write(image[minor].resource, + image[minor].kern_buf, copied, *ppos); + } else { + /* XXX Need to write this */ + printk("Currently don't support large transfers\n"); + /* Map in pages from userspace */ + + /* Call vme_master_write to do the transfer */ + return -EINVAL; + } + + return copied; +} + +static ssize_t buffer_to_user(unsigned int minor, char __user *buf, + size_t count, loff_t *ppos) +{ + void __iomem *image_ptr; + ssize_t retval; + + image_ptr = image[minor].kern_buf + *ppos; + + retval = __copy_to_user(buf, image_ptr, (unsigned long)count); + if (retval != 0) { + retval = (count - retval); + printk(KERN_WARNING "Partial copy to userspace\n"); + } else + retval = count; + + /* Return number of bytes successfully read */ + return retval; +} + +static ssize_t buffer_from_user(unsigned int minor, const char *buf, + size_t count, loff_t *ppos) +{ + void __iomem *image_ptr; + size_t retval; + + image_ptr = image[minor].kern_buf + *ppos; + + retval = __copy_from_user(image_ptr, buf, (unsigned long)count); + if (retval != 0) { + retval = (count - retval); + printk(KERN_WARNING "Partial copy to userspace\n"); + } else + retval = count; + + /* Return number of bytes successfully read */ + return retval; +} + +static ssize_t vme_user_read(struct file *file, char *buf, size_t count, + loff_t * ppos) +{ + unsigned int minor = MINOR(file->f_dentry->d_inode->i_rdev); + ssize_t retval; + size_t image_size; + size_t okcount; + + down(&image[minor].sem); + + /* XXX Do we *really* want this helper - we can use vme_*_get ? */ + image_size = vme_get_size(image[minor].resource); + + /* Ensure we are starting at a valid location */ + if ((*ppos < 0) || (*ppos > (image_size - 1))) { + up(&image[minor].sem); + return 0; + } + + /* Ensure not reading past end of the image */ + if (*ppos + count > image_size) + okcount = image_size - *ppos; + else + okcount = count; + + switch (type[minor]){ + case MASTER_MINOR: + retval = resource_to_user(minor, buf, okcount, ppos); + break; + case SLAVE_MINOR: + retval = buffer_to_user(minor, buf, okcount, ppos); + break; + default: + retval = -EINVAL; + } + + up(&image[minor].sem); + + if (retval > 0) + *ppos += retval; + + return retval; +} + +static ssize_t vme_user_write(struct file *file, const char *buf, size_t count, + loff_t *ppos) +{ + unsigned int minor = MINOR(file->f_dentry->d_inode->i_rdev); + ssize_t retval; + size_t image_size; + size_t okcount; + + down(&image[minor].sem); + + image_size = vme_get_size(image[minor].resource); + + /* Ensure we are starting at a valid location */ + if ((*ppos < 0) || (*ppos > (image_size - 1))) { + up(&image[minor].sem); + return 0; + } + + /* Ensure not reading past end of the image */ + if (*ppos + count > image_size) + okcount = image_size - *ppos; + else + okcount = count; + + switch (type[minor]){ + case MASTER_MINOR: + retval = resource_from_user(minor, buf, okcount, ppos); + break; + case SLAVE_MINOR: + retval = buffer_from_user(minor, buf, okcount, ppos); + break; + default: + retval = -EINVAL; + } + + up(&image[minor].sem); + + if (retval > 0) + *ppos += retval; + + return retval; +} + +static loff_t vme_user_llseek(struct file *file, loff_t off, int whence) +{ + printk(KERN_ERR "Llseek currently incomplete\n"); + return -EINVAL; +} + +/* + * The ioctls provided by the old VME access method (the one at vmelinux.org) + * are most certainly wrong as the effectively push the registers layout + * through to user space. Given that the VME core can handle multiple bridges, + * with different register layouts this is most certainly not the way to go. + * + * We aren't using the structures defined in the Motorola driver either - these + * are also quite low level, however we should use the definitions that have + * already been defined. + */ +static int vme_user_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct vme_master master; + struct vme_slave slave; + unsigned long copied; + unsigned int minor = MINOR(inode->i_rdev); + int retval; + dma_addr_t pci_addr; + + statistics.ioctls++; + + switch (type[minor]) { + case CONTROL_MINOR: + break; + case MASTER_MINOR: + switch (cmd) { + case VME_GET_MASTER: + memset(&master, 0, sizeof(struct vme_master)); + + /* XXX We do not want to push aspace, cycle and width + * to userspace as they are + */ + retval = vme_master_get(image[minor].resource, + &(master.enable), &(master.vme_addr), + &(master.size), &(master.aspace), + &(master.cycle), &(master.dwidth)); + + copied = copy_to_user((char *)arg, &master, + sizeof(struct vme_master)); + if (copied != 0) { + printk(KERN_WARNING "Partial copy to " + "userspace\n"); + return -EFAULT; + } + + return retval; + break; + + case VME_SET_MASTER: + + copied = copy_from_user(&master, (char *)arg, + sizeof(master)); + if (copied != 0) { + printk(KERN_WARNING "Partial copy from " + "userspace\n"); + return -EFAULT; + } + + /* XXX We do not want to push aspace, cycle and width + * to userspace as they are + */ + return vme_master_set(image[minor].resource, + master.enable, master.vme_addr, master.size, + master.aspace, master.cycle, master.dwidth); + + break; + } + break; + case SLAVE_MINOR: + switch (cmd) { + case VME_GET_SLAVE: + memset(&slave, 0, sizeof(struct vme_slave)); + + /* XXX We do not want to push aspace, cycle and width + * to userspace as they are + */ + retval = vme_slave_get(image[minor].resource, + &(slave.enable), &(slave.vme_addr), + &(slave.size), &pci_addr, &(slave.aspace), + &(slave.cycle)); + + copied = copy_to_user((char *)arg, &slave, + sizeof(struct vme_slave)); + if (copied != 0) { + printk(KERN_WARNING "Partial copy to " + "userspace\n"); + return -EFAULT; + } + + return retval; + break; + + case VME_SET_SLAVE: + + copied = copy_from_user(&slave, (char *)arg, + sizeof(slave)); + if (copied != 0) { + printk(KERN_WARNING "Partial copy from " + "userspace\n"); + return -EFAULT; + } + + /* XXX We do not want to push aspace, cycle and width + * to userspace as they are + */ + return vme_slave_set(image[minor].resource, + slave.enable, slave.vme_addr, slave.size, + image[minor].pci_buf, slave.aspace, + slave.cycle); + + break; + } + break; + } + + return -EINVAL; +} + + +/* + * Unallocate a previously allocated buffer + */ +static void buf_unalloc (int num) +{ + if (image[num].kern_buf) { +#ifdef VME_DEBUG + printk(KERN_DEBUG "UniverseII:Releasing buffer at %p\n", + image[num].pci_buf); +#endif + + vme_free_consistent(image[num].resource, image[num].size_buf, + image[num].kern_buf, image[num].pci_buf); + + image[num].kern_buf = NULL; + image[num].pci_buf = 0; + image[num].size_buf = 0; + +#ifdef VME_DEBUG + } else { + printk(KERN_DEBUG "UniverseII: Buffer not allocated\n"); +#endif + } +} + +static struct vme_driver vme_user_driver = { + .name = driver_name, + .probe = vme_user_probe, + .remove = vme_user_remove, +}; + + +static int __init vme_user_init(void) +{ + int retval = 0; + int i; + struct vme_device_id *ids; + + printk(KERN_INFO "VME User Space Access Driver\n"); + + if (bus_num == 0) { + printk(KERN_ERR "%s: No cards, skipping registration\n", + driver_name); + goto err_nocard; + } + + /* Let's start by supporting one bus, we can support more than one + * in future revisions if that ever becomes necessary. + */ + if (bus_num > USER_BUS_MAX) { + printk(KERN_ERR "%s: Driver only able to handle %d PIO2 " + "Cards\n", driver_name, USER_BUS_MAX); + bus_num = USER_BUS_MAX; + } + + + /* Dynamically create the bind table based on module parameters */ + ids = kmalloc(sizeof(struct vme_device_id) * (bus_num + 1), GFP_KERNEL); + if (ids == NULL) { + printk(KERN_ERR "%s: Unable to allocate ID table\n", + driver_name); + goto err_id; + } + + memset(ids, 0, (sizeof(struct vme_device_id) * (bus_num + 1))); + + for (i = 0; i < bus_num; i++) { + ids[i].bus = bus[i]; + /* + * We register the driver against the slot occupied by *this* + * card, since it's really a low level way of controlling + * the VME bridge + */ + ids[i].slot = VME_SLOT_CURRENT; + } + + vme_user_driver.bind_table = ids; + + retval = vme_register_driver(&vme_user_driver); + if (retval != 0) + goto err_reg; + + return retval; + + vme_unregister_driver(&vme_user_driver); +err_reg: + kfree(ids); +err_id: +err_nocard: + return retval; +} + +/* + * In this simple access driver, the old behaviour is being preserved as much + * as practical. We will therefore reserve the buffers and request the images + * here so that we don't have to do it later. + */ +static int __init vme_user_probe(struct device *dev, int cur_bus, int cur_slot) +{ + int i, err; + char name[8]; + + /* Save pointer to the bridge device */ + if (vme_user_bridge != NULL) { + printk(KERN_ERR "%s: Driver can only be loaded for 1 device\n", + driver_name); + err = -EINVAL; + goto err_dev; + } + vme_user_bridge = dev; + + /* Initialise descriptors */ + for (i = 0; i < VME_DEVS; i++) { + image[i].kern_buf = NULL; + image[i].pci_buf = 0; + init_MUTEX(&(image[i].sem)); + image[i].device = NULL; + image[i].resource = NULL; + image[i].users = 0; + } + + /* Initialise statistics counters */ + reset_counters(); + + /* Assign major and minor numbers for the driver */ + err = register_chrdev_region(MKDEV(VME_MAJOR, 0), VME_DEVS, + driver_name); + if (err) { + printk(KERN_WARNING "%s: Error getting Major Number %d for " + "driver.\n", driver_name, VME_MAJOR); + goto err_region; + } + + /* Register the driver as a char device */ + vme_user_cdev = cdev_alloc(); + vme_user_cdev->ops = &vme_user_fops; + vme_user_cdev->owner = THIS_MODULE; + err = cdev_add(vme_user_cdev, MKDEV(VME_MAJOR, 0), VME_DEVS); + if (err) { + printk(KERN_WARNING "%s: cdev_all failed\n", driver_name); + goto err_char; + } + + /* Request slave resources and allocate buffers (128kB wide) */ + for (i = SLAVE_MINOR; i < (SLAVE_MAX + 1); i++) { + /* XXX Need to properly request attributes */ + image[i].resource = vme_slave_request(vme_user_bridge, + VME_A16, VME_SCT); + if (image[i].resource == NULL) { + printk(KERN_WARNING "Unable to allocate slave " + "resource\n"); + goto err_slave; + } + image[i].size_buf = PCI_BUF_SIZE; + image[i].kern_buf = vme_alloc_consistent(image[i].resource, + image[i].size_buf, &(image[i].pci_buf)); + if (image[i].kern_buf == NULL) { + printk(KERN_WARNING "Unable to allocate memory for " + "buffer\n"); + image[i].pci_buf = 0; + vme_slave_free(image[i].resource); + err = -ENOMEM; + goto err_slave; + } + } + + /* + * Request master resources allocate page sized buffers for small + * reads and writes + */ + for (i = MASTER_MINOR; i < (MASTER_MAX + 1); i++) { + /* XXX Need to properly request attributes */ + image[i].resource = vme_master_request(vme_user_bridge, + VME_A32, VME_SCT, VME_D32); + if (image[i].resource == NULL) { + printk(KERN_WARNING "Unable to allocate master " + "resource\n"); + goto err_master; + } + } + + /* Create sysfs entries - on udev systems this creates the dev files */ + vme_user_sysfs_class = class_create(THIS_MODULE, driver_name); + if (IS_ERR(vme_user_sysfs_class)) { + printk(KERN_ERR "Error creating vme_user class.\n"); + err = PTR_ERR(vme_user_sysfs_class); + goto err_class; + } + + /* Add sysfs Entries */ + for (i=0; i<VME_DEVS; i++) { + switch (type[i]) { + case MASTER_MINOR: + sprintf(name,"bus/vme/m%%d"); + break; + case CONTROL_MINOR: + sprintf(name,"bus/vme/ctl"); + break; + case SLAVE_MINOR: + sprintf(name,"bus/vme/s%%d"); + break; + default: + err = -EINVAL; + goto err_sysfs; + break; + } + + image[i].device = + device_create(vme_user_sysfs_class, NULL, + MKDEV(VME_MAJOR, i), NULL, name, + (type[i] == SLAVE_MINOR)? i - (MASTER_MAX + 1) : i); + if (IS_ERR(image[i].device)) { + printk("%s: Error creating sysfs device\n", + driver_name); + err = PTR_ERR(image[i].device); + goto err_sysfs; + } + } + + return 0; + + /* Ensure counter set correcty to destroy all sysfs devices */ + i = VME_DEVS; +err_sysfs: + while (i > 0){ + i--; + device_destroy(vme_user_sysfs_class, MKDEV(VME_MAJOR, i)); + } + class_destroy(vme_user_sysfs_class); + + /* Ensure counter set correcty to unalloc all master windows */ + i = MASTER_MAX + 1; +err_master: + while (i > MASTER_MINOR) { + i--; + vme_master_free(image[i].resource); + } + + /* + * Ensure counter set correcty to unalloc all slave windows and buffers + */ + i = SLAVE_MAX + 1; +err_slave: + while (i > SLAVE_MINOR) { + i--; + vme_slave_free(image[i].resource); + buf_unalloc(i); + } +err_class: + cdev_del(vme_user_cdev); +err_char: + unregister_chrdev_region(MKDEV(VME_MAJOR, 0), VME_DEVS); +err_region: +err_dev: + return err; +} + +static int __exit vme_user_remove(struct device *dev, int cur_bus, int cur_slot) +{ + int i; + + /* Remove sysfs Entries */ + for(i=0; i<VME_DEVS; i++) { + device_destroy(vme_user_sysfs_class, MKDEV(VME_MAJOR, i)); + } + class_destroy(vme_user_sysfs_class); + + for (i = SLAVE_MINOR; i < (SLAVE_MAX + 1); i++) { + vme_slave_set(image[i].resource, 0, 0, 0, 0, VME_A32, 0); + vme_slave_free(image[i].resource); + buf_unalloc(i); + } + + /* Unregister device driver */ + cdev_del(vme_user_cdev); + + /* Unregiser the major and minor device numbers */ + unregister_chrdev_region(MKDEV(VME_MAJOR, 0), VME_DEVS); + + return 0; +} + +static void __exit vme_user_exit(void) +{ + vme_unregister_driver(&vme_user_driver); + + kfree(vme_user_driver.bind_table); +} + + +MODULE_PARM_DESC(bus, "Enumeration of VMEbus to which the driver is connected"); +module_param_array(bus, int, &bus_num, 0); + +MODULE_DESCRIPTION("VME User Space Access Driver"); +MODULE_AUTHOR("Martyn Welch <martyn.welch@gefanuc.com"); +MODULE_LICENSE("GPL"); + +module_init(vme_user_init); +module_exit(vme_user_exit); |