All of lore.kernel.org
 help / color / mirror / Atom feed
From: Gavin Shan <gwshan@linux.vnet.ibm.com>
To: linux-pci@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org, bhelgaas@google.com,
	benh@au1.ibm.com, benh@kernel.crashing.org, mpe@ellerman.id.au,
	clsoto@us.ibm.com, Gavin Shan <gwshan@linux.vnet.ibm.com>
Subject: [PATCH v2 2/2] PCI: Don't disable PF's memory decoding when enabling SRIOV
Date: Fri, 30 Sep 2016 09:47:50 +1000	[thread overview]
Message-ID: <1475192870-7763-2-git-send-email-gwshan@linux.vnet.ibm.com> (raw)
In-Reply-To: <1475192870-7763-1-git-send-email-gwshan@linux.vnet.ibm.com>

pci_update_resource() might be called to update (shift) IOV BARs
in PPC PowerNV specific pcibios_sriov_enable() when enabling PF's
SRIOV capability. At that point, the PF have been functional if
the SRIOV is enabled through sysfs entry "sriov_numvfs". The PF's
memory decoding (0x2 in PCI_COMMAND) shouldn't be disabled when
updating its IOV BARs with pci_update_resource(). Otherwise, we
receives EEH error caused by MMIO access to PF's memory BARs during
the window when PF's memory decoding is disabled.

   sriov_numvfs_store
   pdev->driver->sriov_configure
   mlx5_core_sriov_configure
   pci_enable_sriov
   sriov_enable
   pcibios_sriov_enable
   pnv_pci_sriov_enable
   pnv_pci_vf_resource_shift
   pci_update_resource

This doesn't change the PF's memory decoding in the path by introducing
additional parameter (@mmio_force_on) to pci_update_resource() in
the above path.

Reported-by: Carol Soto <clsoto@us.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Carol Soto <clsoto@us.ibm.com>
---
 arch/powerpc/platforms/powernv/pci-ioda.c | 2 +-
 drivers/pci/iov.c                         | 2 +-
 drivers/pci/pci.c                         | 2 +-
 drivers/pci/setup-res.c                   | 9 +++++----
 include/linux/pci.h                       | 2 +-
 5 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 38a5c65..f4ccc5b 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1006,7 +1006,7 @@ static int pnv_pci_vf_resource_shift(struct pci_dev *dev, int offset)
 		dev_info(&dev->dev, "VF BAR%d: %pR shifted to %pR (%sabling %d VFs shifted by %d)\n",
 			 i, &res2, res, (offset > 0) ? "En" : "Dis",
 			 num_vfs, offset);
-		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
+		pci_update_resource(dev, i + PCI_IOV_RESOURCES, true);
 	}
 	return 0;
 }
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index f1343f0..db31966 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -511,7 +511,7 @@ static void sriov_restore_state(struct pci_dev *dev)
 		return;
 
 	for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
-		pci_update_resource(dev, i);
+		pci_update_resource(dev, i, false);
 
 	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
 	pci_iov_set_numvfs(dev, iov->num_VFs);
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index aab9d51..87a33c0 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -545,7 +545,7 @@ static void pci_restore_bars(struct pci_dev *dev)
 		return;
 
 	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
-		pci_update_resource(dev, i);
+		pci_update_resource(dev, i, false);
 }
 
 static const struct pci_platform_pm_ops *pci_platform_pm;
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index 66c4d8f..e8a50ff 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -26,7 +26,7 @@
 #include "pci.h"
 
 
-void pci_update_resource(struct pci_dev *dev, int resno)
+void pci_update_resource(struct pci_dev *dev, int resno, bool mmio_force_on)
 {
 	struct pci_bus_region region;
 	bool disable;
@@ -81,7 +81,8 @@ void pci_update_resource(struct pci_dev *dev, int resno)
 	 * disable decoding so that a half-updated BAR won't conflict
 	 * with another device.
 	 */
-	disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
+	disable = (res->flags & IORESOURCE_MEM_64) &&
+		  !mmio_force_on && !dev->mmio_always_on;
 	if (disable) {
 		pci_read_config_word(dev, PCI_COMMAND, &cmd);
 		pci_write_config_word(dev, PCI_COMMAND,
@@ -310,7 +311,7 @@ int pci_assign_resource(struct pci_dev *dev, int resno)
 	res->flags &= ~IORESOURCE_STARTALIGN;
 	dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
 	if (resno < PCI_BRIDGE_RESOURCES)
-		pci_update_resource(dev, resno);
+		pci_update_resource(dev, resno, false);
 
 	return 0;
 }
@@ -350,7 +351,7 @@ int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsiz
 	dev_info(&dev->dev, "BAR %d: reassigned %pR (expanded by %#llx)\n",
 		 resno, res, (unsigned long long) addsize);
 	if (resno < PCI_BRIDGE_RESOURCES)
-		pci_update_resource(dev, resno);
+		pci_update_resource(dev, resno, false);
 
 	return 0;
 }
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 0ab8359..99231d1 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1039,7 +1039,7 @@ int pci_try_reset_bus(struct pci_bus *bus);
 void pci_reset_secondary_bus(struct pci_dev *dev);
 void pcibios_reset_secondary_bus(struct pci_dev *dev);
 void pci_reset_bridge_secondary_bus(struct pci_dev *dev);
-void pci_update_resource(struct pci_dev *dev, int resno);
+void pci_update_resource(struct pci_dev *dev, int resno, bool mmio_force_on);
 int __must_check pci_assign_resource(struct pci_dev *dev, int i);
 int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size_t add_size, resource_size_t align);
 int pci_select_bars(struct pci_dev *dev, unsigned long flags);
-- 
2.1.0


  reply	other threads:[~2016-09-29 23:53 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-29 23:47 [PATCH v2 1/2] pci: Call pcibios_sriov_enable() before IOV BARs are enabled Gavin Shan
2016-09-29 23:47 ` Gavin Shan [this message]
2016-10-21 16:50   ` [PATCH v2 2/2] PCI: Don't disable PF's memory decoding when enabling SRIOV Bjorn Helgaas
2016-10-23 23:28     ` Gavin Shan
2016-10-24 14:03       ` Bjorn Helgaas
2016-10-25  1:47         ` Gavin Shan
2016-10-25  3:51           ` Bjorn Helgaas
2016-10-26  1:02             ` Gavin Shan
2016-10-11  5:33 ` [PATCH v2 1/2] pci: Call pcibios_sriov_enable() before IOV BARs are enabled Gavin Shan
2016-10-21 20:23 ` Bjorn Helgaas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1475192870-7763-2-git-send-email-gwshan@linux.vnet.ibm.com \
    --to=gwshan@linux.vnet.ibm.com \
    --cc=benh@au1.ibm.com \
    --cc=benh@kernel.crashing.org \
    --cc=bhelgaas@google.com \
    --cc=clsoto@us.ibm.com \
    --cc=linux-pci@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.