From: sathyanarayanan.kuppuswamy@linux.intel.com
To: bhelgaas@google.com, joro@8bytes.org, dwmw2@infradead.org
Cc: linux-pci@vger.kernel.org, iommu@lists.linux-foundation.org,
linux-kernel@vger.kernel.org, ashok.raj@intel.com,
jacob.jun.pan@intel.com, keith.busch@intel.com,
Jacob Pan <jacob.jun.pan@linux.intel.com>,
Kuppuswamy Sathyanarayanan
<sathyanarayanan.kuppuswamy@linux.intel.com>
Subject: [PATCH v1 1/2] PCI: ATS: Add function to check PRG response PASID bit status.
Date: Thu, 7 Feb 2019 10:37:58 -0800 [thread overview]
Message-ID: <2be716037209f722304e94da6df39aec5a37f236.1549479043.git.sathyanarayanan.kuppuswamy@linux.intel.com> (raw)
In-Reply-To: <cover.1549479043.git.sathyanarayanan.kuppuswamy@linux.intel.com>
From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Add a new function to return the status of PRG response PASID
required bit in PRI status register. This function will be used by
drivers like IOMMU, if it is required to enforce the PASID required for
page-group responses.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
---
drivers/pci/ats.c | 27 +++++++++++++++++++++++++++
include/linux/pci-ats.h | 5 +++++
include/uapi/linux/pci_regs.h | 1 +
3 files changed, 33 insertions(+)
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index 5b78f3b1b918..666d03332944 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -368,6 +368,33 @@ int pci_pasid_features(struct pci_dev *pdev)
}
EXPORT_SYMBOL_GPL(pci_pasid_features);
+/**
+ * pci_pggrp_rsp_need_pasid - Return PRG response PASID required bit status.
+ * @pdev: PCI device structure
+ *
+ * Returns positive if PASID is required, 0 otherwise.
+ *
+ * Eventhough the PRG response PASID status is read from PRI status
+ * register, Since this API will mainly be used by PASID users, this
+ * function is defined within #ifdef CONFIG_PCI_PASID instead of
+ * CONFIG_PCI_PRI.
+ *
+ */
+int pci_pggrp_rsp_need_pasid(struct pci_dev *pdev)
+{
+ u16 status;
+ int pos;
+
+ pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
+ if (!pos)
+ return 0;
+
+ pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status);
+
+ return status & PCI_PRI_STATUS_PASID;
+}
+EXPORT_SYMBOL_GPL(pci_pggrp_rsp_need_pasid);
+
#define PASID_NUMBER_SHIFT 8
#define PASID_NUMBER_MASK (0x1f << PASID_NUMBER_SHIFT)
/**
diff --git a/include/linux/pci-ats.h b/include/linux/pci-ats.h
index 7c4b8e27268c..ea29c7c64482 100644
--- a/include/linux/pci-ats.h
+++ b/include/linux/pci-ats.h
@@ -40,6 +40,7 @@ void pci_disable_pasid(struct pci_dev *pdev);
void pci_restore_pasid_state(struct pci_dev *pdev);
int pci_pasid_features(struct pci_dev *pdev);
int pci_max_pasids(struct pci_dev *pdev);
+int pci_pggrp_rsp_need_pasid(struct pci_dev *pdev);
#else /* CONFIG_PCI_PASID */
@@ -66,6 +67,10 @@ static inline int pci_max_pasids(struct pci_dev *pdev)
return -EINVAL;
}
+static int pci_pggrp_rsp_need_pasid(struct pci_dev *pdev)
+{
+ return 0;
+}
#endif /* CONFIG_PCI_PASID */
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index e1e9888c85e6..898be572b010 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -880,6 +880,7 @@
#define PCI_PRI_STATUS_RF 0x001 /* Response Failure */
#define PCI_PRI_STATUS_UPRGI 0x002 /* Unexpected PRG index */
#define PCI_PRI_STATUS_STOPPED 0x100 /* PRI Stopped */
+#define PCI_PRI_STATUS_PASID 0x8000 /* PRG Response PASID Required */
#define PCI_PRI_MAX_REQ 0x08 /* PRI max reqs supported */
#define PCI_PRI_ALLOC_REQ 0x0c /* PRI max reqs allowed */
#define PCI_EXT_CAP_PRI_SIZEOF 16
--
2.20.1
next prev parent reply other threads:[~2019-02-07 18:41 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-07 18:37 [PATCH v1 0/2] Add PGR response PASID requirement check in Intel IOMMU sathyanarayanan.kuppuswamy
2019-02-07 18:37 ` sathyanarayanan.kuppuswamy [this message]
2019-02-07 20:35 ` [PATCH v1 1/2] PCI: ATS: Add function to check PRG response PASID bit status Bjorn Helgaas
2019-02-07 18:37 ` [PATCH v1 2/2] iommu/vt-d: Enable PASID only if device expects PASID in PRG response sathyanarayanan.kuppuswamy
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=2be716037209f722304e94da6df39aec5a37f236.1549479043.git.sathyanarayanan.kuppuswamy@linux.intel.com \
--to=sathyanarayanan.kuppuswamy@linux.intel.com \
--cc=ashok.raj@intel.com \
--cc=bhelgaas@google.com \
--cc=dwmw2@infradead.org \
--cc=iommu@lists.linux-foundation.org \
--cc=jacob.jun.pan@intel.com \
--cc=jacob.jun.pan@linux.intel.com \
--cc=joro@8bytes.org \
--cc=keith.busch@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).