lkml.org 
[lkml]   [2019]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC PATCH 2/5] drivers/base: add a function to test peer to peer capability
Date
From: Jérôme Glisse <jglisse@redhat.com>

device_test_p2p() return true if two devices can peer to peer to
each other. We add a generic function as different inter-connect
can support peer to peer and we want to genericaly test this no
matter what the inter-connect might be. However this version only
support PCIE for now.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: iommu@lists.linux-foundation.org
---
drivers/base/core.c | 20 ++++++++++++++++++++
include/linux/device.h | 1 +
2 files changed, 21 insertions(+)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 0073b09bb99f..56023b00e108 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -26,6 +26,7 @@
#include <linux/netdevice.h>
#include <linux/sched/signal.h>
#include <linux/sysfs.h>
+#include <linux/pci-p2pdma.h>

#include "base.h"
#include "power/power.h"
@@ -3167,3 +3168,22 @@ void device_set_of_node_from_dev(struct device *dev, const struct device *dev2)
dev->of_node_reused = true;
}
EXPORT_SYMBOL_GPL(device_set_of_node_from_dev);
+
+/**
+ * device_test_p2p - test if two device can peer to peer to each other
+ * @devA: device A
+ * @devB: device B
+ * Returns: true if device can peer to peer to each other, false otherwise
+ */
+bool device_test_p2p(struct device *devA, struct device *devB)
+{
+ /*
+ * For now we only support PCIE peer to peer but other inter-connect
+ * can be added.
+ */
+ if (pci_test_p2p(devA, devB))
+ return true;
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(device_test_p2p);
diff --git a/include/linux/device.h b/include/linux/device.h
index 6cb4640b6160..0d532d7f0779 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -1250,6 +1250,7 @@ extern int device_online(struct device *dev);
extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
+bool device_test_p2p(struct device *devA, struct device *devB);

static inline int dev_num_vf(struct device *dev)
{
--
2.17.2
\
 
 \ /
  Last update: 2019-01-29 18:48    [W:0.184 / U:66.408 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site