Staging: vme: add VME userspace driver (f00a86d9) · Commits · jan.koester / Linux

drivers/staging/vme/Kconfig

+2 −2

Original line number	Diff line number	Diff line
		@@ -11,7 +11,7 @@ menuconfig VME
		if VME

		#source "drivers/staging/vme/bridges/Kconfig"
		#
		#source "drivers/staging/vme/devices/Kconfig"

		source "drivers/staging/vme/devices/Kconfig"

		endif # VME

drivers/staging/vme/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -4,4 +4,4 @@
		obj-$(CONFIG_VME) += vme.o

		#obj-y += bridges/
		#obj-y += devices/
		obj-y += devices/

drivers/staging/vme/devices/Kconfig

0 → 100644

+8 −0

Original line number	Diff line number	Diff line
		comment "VME Device Drivers"

		config VME_USER
		tristate "VME user space access driver"
		help
		If you say Y here you want to be able to access a limited number of
		VME windows in a manner at least semi-compatible with the interface
		provided with the original driver at http://vmelinux.org/.

drivers/staging/vme/devices/Makefile

0 → 100644

+5 −0

Original line number	Diff line number	Diff line
		#
		# Makefile for the VME device drivers.
		#

		obj-$(CONFIG_VME_USER) += vme_user.o

drivers/staging/vme/devices/vme_user.c

0 → 100644

+771 −0

Original line number	Diff line number	Diff line
		/*
		* 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"

		/* 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.
		*/
		#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 char driver_name[] = "vme_user";

		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 *dev);

		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;
		}

		void lmcall(int monitor)
		{
		printk("Caught Location Monitor %d access\n", monitor);
		}

		static void tests(void)
		{
		struct vme_resource *dma_res;
		struct vme_dma_list *dma_list;
		struct vme_dma_attr pattern_attr, vme_attr;

		int retval;
		unsigned int data;

		printk("Running VME DMA test\n");
		dma_res = vme_request_dma(vme_user_bridge);
		dma_list = vme_new_dma_list(dma_res);
		pattern_attr = vme_dma_pattern_attribute(0x0,
		VME_DMA_PATTERN_WORD \|
		VME_DMA_PATTERN_INCREMENT);
		vme_attr = vme_dma_vme_attribute(0x10000, VME_A32,
		VME_SCT, VME_D32);
		retval = vme_dma_list_add(dma_list, pattern_attr,
		vme_attr, 0x10000);
		#if 0
		vme_dma_free_attribute(vme_attr);
		vme_attr = vme_dma_vme_attribute(0x20000, VME_A32,
		VME_SCT, VME_D32);
		retval = vme_dma_list_add(dma_list, pattern_attr,
		vme_attr, 0x10000);
		#endif
		retval = vme_dma_list_exec(dma_list);
		vme_dma_free_attribute(pattern_attr);
		vme_dma_free_attribute(vme_attr);
		vme_dma_list_free(dma_list);
		#if 0
		printk("Generating a VME interrupt\n");
		vme_generate_irq(dma_res, 0x3, 0xaa);
		printk("Interrupt returned\n");
		#endif
		vme_dma_free(dma_res);

		/* Attempt RMW */
		data = vme_master_rmw(image[0].resource, 0x80000000, 0x00000000,
		0x80000000, 0);
		printk("RMW returned 0x%8.8x\n", data);


		/* Location Monitor */
		printk("vme_lm_set:%d\n", vme_lm_set(vme_user_bridge, 0x60000, VME_A32, VME_SCT \| VME_USER \| VME_DATA));
		printk("vme_lm_attach:%d\n", vme_lm_attach(vme_user_bridge, 0, lmcall));

		printk("Board in VME slot:%d\n", vme_slot_get(vme_user_bridge));
		}

		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;
		}

		static int vme_user_ioctl(struct inode inode, struct file file,
		unsigned int cmd, unsigned long arg)
		{
		unsigned int minor = MINOR(inode->i_rdev);
		#if 0
		int ret_val;
		#endif
		unsigned long copyRet;
		vme_slave_t slave;

		statistics.ioctls++;
		switch (type[minor]) {
		case CONTROL_MINOR:
		break;
		case MASTER_MINOR:
		break;
		case SLAVE_MINOR:
		switch (cmd) {
		case VME_SET_SLAVE:

		copyRet = copy_from_user(&slave, (char *)arg,
		sizeof(slave));
		if (copyRet != 0) {
		printk(KERN_WARNING "Partial copy from "
		"userspace\n");
		return -EFAULT;
		}

		return vme_slave_set(image[minor].resource,
		slave.enable, slave.vme_addr, slave.size,
		image[minor].pci_buf, slave.aspace,
		slave.cycle);

		break;
		#if 0
		case VME_GET_SLAVE:
		vme_slave_t slave;

		ret_val = vme_slave_get(minor, &iRegs);

		copyRet = copy_to_user((char *)arg, &slave,
		sizeof(slave));
		if (copyRet != 0) {
		printk(KERN_WARNING "Partial copy to "
		"userspace\n");
		return -EFAULT;
		}

		return ret_val;
		break;
		#endif
		}
		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,
		};


		/*
		* 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_bridge_init(void)
		{
		int retval;
		printk(KERN_INFO "VME User Space Access Driver\n");
		printk("vme_user_driver:%p\n", &vme_user_driver);
		retval = vme_register_driver(&vme_user_driver);
		printk("vme_register_driver returned %d\n", retval);
		return retval;
		}

		/*
		* This structure gets passed a device, this should be the device created at
		* registration.
		*/
		static int __init vme_user_probe(struct device *dev)
		{
		int i, err;
		char name[8];

		printk("Running vme_user_probe()\n");

		/* Pointer to the bridge device */
		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_buf;
		}
		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_buf;
		}
		}

		/*
		* 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_buf;
		}
		image[i].size_buf = PAGE_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_master_free(image[i].resource);
		err = -ENOMEM;
		goto err_buf;
		}
		}

		/* Setup some debug windows */
		for (i = SLAVE_MINOR; i < (SLAVE_MAX + 1); i++) {
		err = vme_slave_set(image[i].resource, 1, 0x4000*(i-4),
		0x4000, image[i].pci_buf, VME_A16,
		VME_SCT \| VME_SUPER \| VME_USER \| VME_PROG \| VME_DATA);
		if (err != 0) {
		printk(KERN_WARNING "Failed to configure window\n");
		goto err_buf;
		}
		}
		for (i = MASTER_MINOR; i < (MASTER_MAX + 1); i++) {
		err = vme_master_set(image[i].resource, 1,
		(0x10000 + (0x10000*i)), 0x10000,
		VME_A32, VME_SCT \| VME_USER \| VME_DATA, VME_D32);
		if (err != 0) {
		printk(KERN_WARNING "Failed to configure window\n");
		goto err_buf;
		}
		}

		/* 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;
		}
		}

		/* XXX Run tests */
		/*
		tests();
		*/

		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 slave buffers */
		i = SLAVE_MAX + 1;
		err_buf:
		while (i > SLAVE_MINOR){
		i--;
		vme_slave_set(image[i].resource, 0, 0, 0, 0, VME_A32, 0);
		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:
		return err;
		}

		static void __exit vme_bridge_exit(void)
		{
		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++) {
		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);
		}

		MODULE_DESCRIPTION("VME User Space Access Driver");
		MODULE_AUTHOR("Martyn Welch <martyn.welch@gefanuc.com");
		MODULE_LICENSE("GPL");

		module_init(vme_bridge_init);
		module_exit(vme_bridge_exit);