xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

PCI/ATS: Add pci_ats_page_aligned() interface

Browse Source 
Return the Page Aligned Request bit in the ATS Capability Register.

As per PCIe spec r4.0, sec 10.5.1.2, if the Page Aligned Request bit is
set, it indicates the Untranslated Addresses generated by the device are
always aligned to a 4096 byte boundary.

An IOMMU that can only translate page-aligned addresses can only be used
with devices that always produce aligned Untranslated Addresses. This
interface will be used by drivers for such IOMMUs to determine whether
devices can use the ATS service.

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>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Kuppuswamy Sathyanarayanan
2019-02-19 11:06:09 -08:00
committed by Joerg Roedel
parent 1b84778a62
commit 8c938ddc6d
3 changed files with 30 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
include/uapi/linux/pci_regs.h
View File

@@ -866,6 +866,7 @@
#define PCI_ATS_CAP 0x04 /* ATS Capability Register */
#define PCI_ATS_CAP_QDEP(x) ((x) & 0x1f) /* Invalidate Queue Depth */
#define PCI_ATS_MAX_QDEP 32 /* Max Invalidate Queue Depth */
#define PCI_ATS_CAP_PAGE_ALIGNED 0x0020 /* Page Aligned Request */
#define PCI_ATS_CTRL 0x06 /* ATS Control Register */
#define PCI_ATS_CTRL_ENABLE 0x8000 /* ATS Enable */
#define PCI_ATS_CTRL_STU(x) ((x) & 0x1f) /* Smallest Translation Unit */