Commit 066f2e98 authored by Alex Williamson's avatar Alex Williamson Committed by Joerg Roedel
Browse files

iommu/amd: Add sysfs support 



AMD-Vi support for IOMMU sysfs.  This allows us to associate devices
with a specific IOMMU device and examine the capabilities and features
of that IOMMU.  The AMD IOMMU is hosted on and actual PCI device, so
we make that device the parent for the IOMMU class device.  This
initial implementaiton exposes only the capability header and extended
features register for the IOMMU.

# find /sys | grep ivhd
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:00.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:02.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:04.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:09.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:11.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:12.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:12.2
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:13.0
...
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/power
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/power/control
...
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/device
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/subsystem
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/amd-iommu
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/amd-iommu/cap
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/amd-iommu/features
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/uevent
/sys/class/iommu/ivhd0

Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent a5459cfe

Documentation/ABI/testing/sysfs-class-iommu-amd-iommu

0 → 100644
+14 −0
Original line number Diff line number Diff line 
What:		/sys/class/iommu/<iommu>/amd-iommu/cap

Date:		June 2014

KernelVersion:	3.17

Contact:	Alex Williamson <alex.williamson@redhat.com>

Description:

		IOMMU capability header as documented in the AMD IOMMU

		specification.  Format: %x



What:		/sys/class/iommu/<iommu>/amd-iommu/features

Date:		June 2014

KernelVersion:	3.17

Contact:	Alex Williamson <alex.williamson@redhat.com>

Description:

		Extended features of the IOMMU.  Format: %llx

drivers/iommu/amd_iommu.c

+6 −0
Original line number Diff line number Diff line
@@ -379,6 +379,9 @@ static int iommu_init_device(struct device *dev) 


	dev->archdata.iommu = dev_data;



	iommu_device_link(amd_iommu_rlookup_table[dev_data->devid]->iommu_dev,

			  dev);



	return 0;

}
@@ -403,6 +406,9 @@ static void iommu_uninit_device(struct device *dev) 
	if (!dev_data)

		return;



	iommu_device_unlink(amd_iommu_rlookup_table[dev_data->devid]->iommu_dev,

			    dev);



	iommu_group_remove_device(dev);



	/* Unlink from alias, it may change if another device is re-plugged */

drivers/iommu/amd_iommu_init.c

+38 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <linux/msi.h>

#include <linux/amd-iommu.h>

#include <linux/export.h>

#include <linux/iommu.h>

#include <asm/pci-direct.h>

#include <asm/iommu.h>

#include <asm/gart.h>
@@ -1197,6 +1198,39 @@ static void init_iommu_perf_ctr(struct amd_iommu *iommu) 
	iommu->max_counters = (u8) ((val >> 7) & 0xf);

}



static ssize_t amd_iommu_show_cap(struct device *dev,

				  struct device_attribute *attr,

				  char *buf)

{

	struct amd_iommu *iommu = dev_get_drvdata(dev);

	return sprintf(buf, "%x\n", iommu->cap);

}

static DEVICE_ATTR(cap, S_IRUGO, amd_iommu_show_cap, NULL);



static ssize_t amd_iommu_show_features(struct device *dev,

				       struct device_attribute *attr,

				       char *buf)

{

	struct amd_iommu *iommu = dev_get_drvdata(dev);

	return sprintf(buf, "%llx\n", iommu->features);

}

static DEVICE_ATTR(features, S_IRUGO, amd_iommu_show_features, NULL);



static struct attribute *amd_iommu_attrs[] = {

	&dev_attr_cap.attr,

	&dev_attr_features.attr,

	NULL,

};



static struct attribute_group amd_iommu_group = {

	.name = "amd-iommu",

	.attrs = amd_iommu_attrs,

};



static const struct attribute_group *amd_iommu_groups[] = {

	&amd_iommu_group,

	NULL,

};



static int iommu_init_pci(struct amd_iommu *iommu)

{
@@ -1297,6 +1331,10 @@ static int iommu_init_pci(struct amd_iommu *iommu) 


	amd_iommu_erratum_746_workaround(iommu);



	iommu->iommu_dev = iommu_device_create(&iommu->dev->dev, iommu,

					       amd_iommu_groups, "ivhd%d",

					       iommu->index);



	return pci_enable_device(iommu->dev);

}

drivers/iommu/amd_iommu_types.h

+3 −0
Original line number Diff line number Diff line
@@ -577,6 +577,9 @@ struct amd_iommu { 
	/* default dma_ops domain for that IOMMU */

	struct dma_ops_domain *default_dom;



	/* IOMMU sysfs device */

	struct device *iommu_dev;



	/*

	 * We can't rely on the BIOS to restore all values on reinit, so we

	 * need to stash them

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