Add mkopci driver

mkopci (MB11.xx) device (RC Module project) provides data transference through a serial bus bar according to MIL-STD-1553. the driver used for operating devices, reads PCI configuration space and pass interrupts to user-space applications.

Please consider adding this patch to the linux-next queue.

From a quick look I'd suggest to get the driver first in shape.

Sergej,

Quoted 2 lines · On Fri, Mar 20, 2015 at 1:10 PM, <[email protected]> wrote:

mkopci (MB11.xx) device (RC Module project) provides data transference through a serial bus bar according to MIL-STD-1553. the driver used for operating devices, reads PCI configuration space and pass interrupts to user-space applications.

Sergej,

Quoted 4 lines · On Fri, Mar 20, 2015 at 1:10 PM, <[email protected]> wrote:

mkopci (MB11.xx) device (RC Module project) provides data transference through a serial bus bar according to MIL-STD-1553. the driver used for operating devices, reads PCI configuration space and pass interrupts to user-space applications.

Please consider adding this patch to the linux-next queue.

From a quick look I'd suggest to get the driver first in shape.

- You add new proc files, which is not really welcomed. Please consider sysfs.
- In the debug prints you compare against current->comm, also not nice.
- You use printk() in the interrupt handler.
- Why is this a misc driver at all? Does it really not fit into any other device class?
- I'm sure running checkpatch.pl against the patch would also not hurt. :)

- You add new proc files, which is not really welcomed. Please consider sysfs.

- In the debug prints you compare against current->comm, also not nice.
- You use printk() in the interrupt handler.

- Why is this a misc driver at all? Does it really not fit into any other device class?

- I'm sure running checkpatch.pl against the patch would also not hurt. :)

BTW: Forgot to mention that this sounds like a job for UIO or VFIO.

Sergej,

Quoted 4 lines · On Fri, Mar 20, 2015 at 1:10 PM, <[email protected]> wrote:

mkopci (MB11.xx) device (RC Module project) provides data transference through a serial bus bar according to MIL-STD-1553. the driver used for operating devices, reads PCI configuration space and pass interrupts to user-space applications.

Please consider adding this patch to the linux-next queue.

From a quick look I'd suggest to get the driver first in shape.

- You add new proc files, which is not really welcomed. Please consider sysfs.
- In the debug prints you compare against current->comm, also not nice.
- You use printk() in the interrupt handler.
- Why is this a misc driver at all? Does it really not fit into any other device class?
- I'm sure running checkpatch.pl against the patch would also not hurt. :)

Richard, thanks for your review.

But I still have several notes about driver:

Quoted 1 line

- You add new proc files, which is not really welcomed. Please consider sysfs.

That will break a bunch of userspace applications, which use proc-files for several years (as long as from 2006 year)

Quoted 1 line

BTW: Forgot to mention that this sounds like a job for UIO or VFIO.

And again, you are right. But, again, there a number of applications wich use /proc/mkopci/core

But, of course, there may be decided that the kernel main line - this is not the place for such a driver. :) If the driver is suitable anyway, patch is at the end of this message

passthrough. In either case, both the ioctl interface and the procfs interface have no future

Quoted 9 lines · Sergej Bauer

Richard, thanks for your review.

But I still have several notes about driver:

Quoted 1 line

- You add new proc files, which is not really welcomed. Please consider sysfs.

That will break a bunch of userspace applications, which use proc-files for several years (as long as from 2006 year)

Quoted 5 lines

Quoted 1 line

BTW: Forgot to mention that this sounds like a job for UIO or VFIO.

And again, you are right. But, again, there a number of applications wich use /proc/mkopci/core

But, of course, there may be decided that the kernel main line - this is not the place for such a driver. :) If the driver is suitable anyway, patch is at the end of this message

I don't think we should merge the driver with the proposed user interface. You can either create a high-level abstraction for MIL-STD-1553, or use UIO or VFIO to provide a trivial passthrough. In either case, both the ioctl interface and the procfs interface have no future, and existing user space programs need to adapt.

There is nothing wrong with adding a driver for this hardware, but I'd rather see it done properly than having an ad-hoc user space interface that was never reviewed publically before it got used by applications.

Arnd

Ok, I realized uselessness of merging this driver...

And you brought me to a standstill:

Quoted 1 line

passthrough. In either case, both the ioctl interface and the procfs interface have no future

But what will be after ioctl?

Am 21.03.2015 um 18:24 schrieb Sergej Bauer:

Quoted 1 line

Ok, I realized uselessness of merging this driver...

Please don't give up that fast!
See: http://airlied.livejournal.com/#item80112

Quoted 3 lines

And you brought me to a standstill:

Quoted 1 line

passthrough. In either case, both the ioctl interface and the procfs interface have no future

But what will be after ioctl?

We will not drop the ioctl() system call. But having a character device with random ioctl()s is not really a good driver design.
Today we have much more elegant ways to interact between kernel and userspace than ioctl(). For example sysfs or netlink.

Thanks,
//richard

mkopci (MB11.xx) device (RC Module project) provides data transference through a serial bus bar according to MIL-STD-1553. the driver used for operating devices, reads PCI configuration space and pass interrupts to user-space applications.

Please consider adding this patch to the linux-next queue.

Signed-off-by Sergej Bauer <[email protected]>

---
 Documentation/misc-devices/mkopci.txt |   51 ++
 drivers/misc/Kconfig                  |    9 +
 drivers/misc/Makefile                 |    1 +
 drivers/misc/mkopci.c                 | 1272 +++++++++++++++++++++++++++++++++
 include/misc/mkopci.h                 |   81 +++
 5 files changed, 1414 insertions(+)

create mode 100644 Documentation/misc-devices/mkopci.txt create mode 100644 drivers/misc/mkopci.c
create mode 100644 include/misc/mkopci.h

Documentation/misc-devices/mkopci.txt new file +12 -0

new file mode 100644
index 0000000..0fcec6d
@@ -0,0 +1,51 @@
+    PCI-based MKO bus driver.
+
+
+For dealing with driver without using of root's account it will be helpfull
+to add group `mkopci' with appropriate users and put file, say 60-mkopci.rules to
+/etc/udev/rules.d in your system.
+--- cut 60-mkopci.rules ---
+# MKO devices
+KERNEL=="mkopci*", SUBSYSTEM=="mkopci", ACTION=="add", DRIVERS=="?*", ATTRS{idVendor}=="0x6403"
+GROUP="mkopci"
+---
+

Documentation/misc-devices/mkopci.txt new file +18 -0

+
+- 'plx9050bug_quirk' controls workaround controller PLX9050. Can
+the following values:
+0 - workaround is disabled (default)
+1 - workaround is enabled
+2 - forced bug
+
+- 'omited' tells the driver which device should not be initialized
+at load time.
+The value of this parameter to the kernel module 2.4 is a physical address
+device on the bus, such as "0x10800" without the quotes.
+In kernel versions 2.6+ can exclude multiple devices, transferring them
+values separated by commas, but not more than 4.
+
+The parameter values can be specified as follows:
+$ insmod/modprobe mkopci.[ko/o] parameter1_name=value [parameter2_name=value]
+
+Record the physical address of the device in the file /proc/mkopci/core

drivers/misc/Kconfig +8 -0

+	tristate "Module PCI bus driver"
+	depends on PCI && PROC_FS
+	help
+	  Say Y here if you want to build a driver for Module(RC) MKOPCI devices.
+
+	  If you choose to build module, its name will be mkopci. If unsure,
+	  say N here.
+
 config INTEL_MID_PTI
 	tristate "Parallel Trace Interface for MIPI P1149.7 cJTAG standard"
 	depends on PCI && TTY && (X86_INTEL_MID || COMPILE_TEST)

drivers/misc/Makefile +1 -0

index 7d5c4cd..afb92b4 100644
@@ -56,3 +56,4 @@ obj-$(CONFIG_GENWQE)		+= genwqe/
 obj-$(CONFIG_ECHO)		+= echo/
 obj-$(CONFIG_VEXPRESS_SYSCFG)	+= vexpress-syscfg.o
 obj-$(CONFIG_CXL_BASE)		+= cxl/
+obj-$(CONFIG_MKOPCI)		+= mkopci.o

drivers/misc/mkopci.c new file +31 -0

new file mode 100644
index 0000000..d223478
@@ -0,0 +1,1272 @@
+/*
+ *  MKOPCI driver
+ *
+ *  Copyright (C) 2007-2015 Sergej Bauer <[email protected]>
+ *
+ *  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, version 2.
+*/
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/pci.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/interrupt.h>
+#include <linux/cdev.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include "misc/mkopci.h"
+
+#define MKO_VENDOR  0x6403
+#define MKO_DEVICE1 0x0430

drivers/misc/mkopci.c new file +5 -0

+
+static struct pci_device_id ids[] = {
+	{MKO_VENDOR, MKO_DEVICE1, PCI_ANY_ID, PCI_ANY_ID,},
+	{MKO_VENDOR, MKO_DEVICE2, PCI_ANY_ID, PCI_ANY_ID,},
+	{MKO_VENDOR, MKO_DEVICE3, PCI_ANY_ID, PCI_ANY_ID,},

drivers/misc/mkopci.c new file +18 -0

+#define mko_pci_addr(bus, device, func, regoffs) (\
+	((bus  & 0xFF) << 16) | ((device & 0x1F) << 11) | \
+	((func & 0x7)  <<  8) | (regoffs & 0xFC))
+
+static struct kmem_cache *mkopci_device_cache;
+static dev_t devp;
+static struct class *mkopci_class;
+static struct rw_semaphore devices_sem;
+static LIST_HEAD(devices);
+static atomic_t devices_nr = ATOMIC_INIT(0);
+
+/*** module parameters ***/
+static int plx9050bug_quirk = 1;
+/* verbosity level */
+static int v;
+module_param(plx9050bug_quirk, int, S_IRUGO);
+module_param(v, int, S_IRUGO);
+MODULE_PARM_DESC(plx9050bug_quirk, "PLX9050 bug quirk");

drivers/misc/mkopci.c new file +4 -0

+
+/***************************** Interrupt handling *****************************/
+static int mkopci_wait_irq(struct mkopci_device *dev)
+{

drivers/misc/mkopci.c new file +47 -0

+		wake_up_interruptible(&mko_dev->wq);
+	} else
+		return IRQ_NONE;
+
+	return IRQ_HANDLED;
+}
+
+static int mkopci_request_irq(struct mkopci_device *dev)
+{
+	int ret = 0;
+
+	if (dev->core.irq_requested) {
+		pr_err("mkopci%d: irq already requested\n", dev->core.n_dev);
+		return -EBUSY;
+	}
+	ret = request_irq(dev->core.irq, &mkopci_int_handler, IRQF_SHARED,
+			dev->core.name, dev);
+	if (ret) {
+		pr_err("mkopci%d: failed to request irq %d\n", dev->core.n_dev,
+			dev->core.irq);
+		return ret;
+	}
+
+	dev->core.irq_requested++;
+
+	if (strcmp(current->comm, "TestSetISR") && v > 1) {
+		pr_info("mkopci%d: irq %d requested (%s)\n", dev->core.n_dev,
+			dev->core.irq, current->comm);
+	}
+
+	return ret;
+}
+
+static void mkopci_free_irq(struct mkopci_device *dev)
+{
+	if (dev->core.irq_requested) {
+		synchronize_irq(dev->core.irq);
+		free_irq(dev->core.irq, dev);
+		dev->core.irq_requested--;
+
+		if (strcmp(current->comm, "TestSetISR") && v > 1) {
+			pr_info("mkopci%d: irq %d released\n", dev->core.n_dev,
+				dev->core.irq);
+		}
+	}
+}
+/************************* End of Interrupt handling **************************/

drivers/misc/mkopci.c new file +10 -0

+
+	if (dev == NULL) {
+		module_put(THIS_MODULE);
+		return -ENODEV;
+	}
+
+	down_write(&dev->rwsem);
+	if (dev->omited) {
+		ret = -ENODEV;
+		goto err;

drivers/misc/mkopci.c new file +16 -0

+	goto out;
+
+err:
+	module_put(THIS_MODULE);
+out:
+	up_write(&dev->rwsem);
+
+	return ret;
+}
+
+static int mkopci_release(struct inode __unused *inode, struct file *filp)
+{
+	struct mkopci_device *dev;
+
+	if (filp->private_data == NULL)
+		return 0;

drivers/misc/mkopci.c new file +23 -0

+		pr_info("mkopci%d: device released\n", dev->core.n_dev);
+	up_write(&dev->rwsem);
+	module_put(THIS_MODULE);
+
+	return 0;
+}
+
+static long mkopci_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	int ret = 0, n = 0;
+	struct mkopci_device *dev =
+	    (struct mkopci_device *)filp->private_data, *d;
+
+	if (_IOC_TYPE(cmd) != MKO_IOC_MAGIC) {
+		pr_err("mkopci%d: _IOC_TYPE(cmd) != MKO_IOC_MAGIC\n",
+			dev->core.n_dev);
+		return -ENOTTY;
+	}
+
+	if (_IOC_NR(cmd) > MKO_IOC_MAXNR) {
+		pr_err("mkopci%d: _IOC_NR(cmd) > MKO_IOC_MAXNR\n",
+			dev->core.n_dev);
+		return -ENOTTY;

drivers/misc/mkopci.c new file +4 -0

+
+	if (ret) {
+		pr_err("mkopci%d: mkopci_ioctl: access_ok failed\n",
+		       dev->core.n_dev);

drivers/misc/mkopci.c new file +4 -0

+		up_read(&dev->rwsem);
+		break;
+	case MKOPCI_IOCTL_GET_DEVICE_TABLE:
+		if (v > 2)

drivers/misc/mkopci.c new file +83 -0

+		up_write(&dev->rwsem);
+		break;
+	case MKOPCI_IOCTL_DETACH_IRQ:
+		if (v > 2)
+			pr_info("mkopci%d: MKOPCI_IOCTL_DETACH_IRQ ioctl\n",
+				dev->core.n_dev);
+		down_write(&dev->rwsem);
+		mkopci_free_irq(dev);
+		up_write(&dev->rwsem);
+		break;
+	case MKOPCI_IOCTL_WAIT_IRQ:
+		if (v > 2)
+			pr_info("mkopci%d: MKOPCI_IOCTL_WAIT_IRQ ioctl\n",
+				dev->core.n_dev);
+		ret = mkopci_wait_irq(dev);
+		break;
+	case MKOPCI_IOCTL_REQUEST_BAR:
+		if (v > 2)
+			pr_info("mkopci%d: MKOPCI_IOCTL_REQUEST_BAR ioctl\n",
+				dev->core.n_dev);
+		down_write(&dev->rwsem);
+		ret = get_user(dev->core.c_bar, (int __user *)arg);
+		up_write(&dev->rwsem);
+		break;
+	default:
+		pr_err("mkopci%d: invalid ioctl %d\n", dev->core.n_dev,
+		       _IOC_NR(cmd));
+		ret = -EINVAL;
+		break;
+	};
+
+	return ret;
+}
+
+#ifndef pgprot_noncached
+static inline pgprot_t pgprot_noncached(pgprot_t _prot)
+{
+	unsigned long prot = pgprot_val(_prot);
+
+	if (boot_cpu_data.x86 > 3)
+		prot |= _PAGE_PCD | _PAGE_PWT;
+
+	return __pgprot(prot);
+}
+#endif
+
+static int mkopci_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	struct mkopci_device *dev = filp->private_data;
+	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+
+	if (dev->core.c_bar == -1) {
+		pr_err("mkopci%d: invalid c_bar number\n", dev->core.n_dev);
+		return -EINVAL;
+	}
+
+	if (vma->vm_pgoff != 0) {
+		pr_err("mkopci%d: vma->vm_pgoff != 0, aborting mapping\n",
+		       dev->core.n_dev);
+		return -EINVAL;
+	}
+
+	if (PAGE_ALIGN(dev->core.mem_size[dev->core.c_bar]) !=
+	    PAGE_ALIGN(vma->vm_end - vma->vm_start)) {
+		pr_err("mkopci%d: PAGE_ALIGN error\n", dev->core.n_dev);
+		return -EINVAL;
+	}
+
+	if (offset >= __pa(high_memory) || (filp->f_flags & O_SYNC))
+		vma->vm_flags |= VM_IO;
+	vma->vm_flags |= VM_RESERVED | VM_SHARED;
+
+	if (v > 1 && strcmp("TstOpenClose", current->comm)) {
+		pr_info
+		    ("mkopci%d: .mmap BAR%d: [0x%lx - 0x%lx], vma [0x%lx - 0x%lx]\n",
+		     dev->core.n_dev, dev->core.c_bar,
+		     dev->core.mem_base[dev->core.c_bar],
+		     dev->core.mem_base[dev->core.c_bar] +
+		     dev->core.mem_size[dev->core.c_bar], vma->vm_start,
+		     vma->vm_end);
+	}
+
+	if (remap_pfn_range