PCI: Restore PRI and PASID state after Function-Level Reset

After a Function-Level Reset, PCI states need to be restored.  Save PASID
features and PRI reqs cached.

[bhelgaas: search for capability only if PRI/PASID were enabled]
Signed-off-by: CQ Tang <cq.tang@intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jean-Phillipe Brucker <jean-philippe.brucker@arm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
This commit is contained in:
CQ Tang 2017-05-30 09:25:49 -07:00 committed by Bjorn Helgaas
parent a4f4fa681a
commit 4ebeb1ec56
4 changed files with 67 additions and 16 deletions

View File

@ -160,17 +160,16 @@ int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
if (!pos)
return -EINVAL;
pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status);
if ((control & PCI_PRI_CTRL_ENABLE) ||
!(status & PCI_PRI_STATUS_STOPPED))
if (!(status & PCI_PRI_STATUS_STOPPED))
return -EBUSY;
pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ, &max_requests);
reqs = min(max_requests, reqs);
pdev->pri_reqs_alloc = reqs;
pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
control |= PCI_PRI_CTRL_ENABLE;
control = PCI_PRI_CTRL_ENABLE;
pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
pdev->pri_enabled = 1;
@ -205,6 +204,28 @@ void pci_disable_pri(struct pci_dev *pdev)
}
EXPORT_SYMBOL_GPL(pci_disable_pri);
/**
* pci_restore_pri_state - Restore PRI
* @pdev: PCI device structure
*/
void pci_restore_pri_state(struct pci_dev *pdev)
{
u16 control = PCI_PRI_CTRL_ENABLE;
u32 reqs = pdev->pri_reqs_alloc;
int pos;
if (!pdev->pri_enabled)
return;
pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
if (!pos)
return;
pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
}
EXPORT_SYMBOL_GPL(pci_restore_pri_state);
/**
* pci_reset_pri - Resets device's PRI state
* @pdev: PCI device structure
@ -224,12 +245,7 @@ int pci_reset_pri(struct pci_dev *pdev)
if (!pos)
return -EINVAL;
pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
if (control & PCI_PRI_CTRL_ENABLE)
return -EBUSY;
control |= PCI_PRI_CTRL_RESET;
control = PCI_PRI_CTRL_RESET;
pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
return 0;
@ -259,12 +275,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
if (!pos)
return -EINVAL;
pci_read_config_word(pdev, pos + PCI_PASID_CTRL, &control);
pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported);
if (control & PCI_PASID_CTRL_ENABLE)
return -EINVAL;
supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
/* User wants to enable anything unsupported? */
@ -272,6 +283,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
return -EINVAL;
control = PCI_PASID_CTRL_ENABLE | features;
pdev->pasid_features = features;
pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
@ -284,7 +296,6 @@ EXPORT_SYMBOL_GPL(pci_enable_pasid);
/**
* pci_disable_pasid - Disable the PASID capability
* @pdev: PCI device structure
*
*/
void pci_disable_pasid(struct pci_dev *pdev)
{
@ -304,6 +315,27 @@ void pci_disable_pasid(struct pci_dev *pdev)
}
EXPORT_SYMBOL_GPL(pci_disable_pasid);
/**
* pci_restore_pasid_state - Restore PASID capabilities
* @pdev: PCI device structure
*/
void pci_restore_pasid_state(struct pci_dev *pdev)
{
u16 control;
int pos;
if (!pdev->pasid_enabled)
return;
pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
if (!pos)
return;
control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features;
pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
}
EXPORT_SYMBOL_GPL(pci_restore_pasid_state);
/**
* pci_pasid_features - Check which PASID features are supported
* @pdev: PCI device structure

View File

@ -28,6 +28,7 @@
#include <linux/pm_runtime.h>
#include <linux/pci_hotplug.h>
#include <linux/vmalloc.h>
#include <linux/pci-ats.h>
#include <asm/setup.h>
#include <asm/dma.h>
#include <linux/aer.h>
@ -1173,6 +1174,8 @@ void pci_restore_state(struct pci_dev *dev)
/* PCI Express register must be restored first */
pci_restore_pcie_state(dev);
pci_restore_pasid_state(dev);
pci_restore_pri_state(dev);
pci_restore_ats_state(dev);
pci_restore_vc_state(dev);

View File

@ -7,6 +7,7 @@
int pci_enable_pri(struct pci_dev *pdev, u32 reqs);
void pci_disable_pri(struct pci_dev *pdev);
void pci_restore_pri_state(struct pci_dev *pdev);
int pci_reset_pri(struct pci_dev *pdev);
#else /* CONFIG_PCI_PRI */
@ -20,6 +21,10 @@ static inline void pci_disable_pri(struct pci_dev *pdev)
{
}
static inline void pci_restore_pri_state(struct pci_dev *pdev)
{
}
static inline int pci_reset_pri(struct pci_dev *pdev)
{
return -ENODEV;
@ -31,6 +36,7 @@ static inline int pci_reset_pri(struct pci_dev *pdev)
int pci_enable_pasid(struct pci_dev *pdev, int features);
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);
@ -45,6 +51,10 @@ static inline void pci_disable_pasid(struct pci_dev *pdev)
{
}
static inline void pci_restore_pasid_state(struct pci_dev *pdev)
{
}
static inline int pci_pasid_features(struct pci_dev *pdev)
{
return -EINVAL;

View File

@ -400,6 +400,12 @@ struct pci_dev {
u16 ats_cap; /* ATS Capability offset */
u8 ats_stu; /* ATS Smallest Translation Unit */
atomic_t ats_ref_cnt; /* number of VFs with ATS enabled */
#endif
#ifdef CONFIG_PCI_PRI
u32 pri_reqs_alloc; /* Number of PRI requests allocated */
#endif
#ifdef CONFIG_PCI_PASID
u16 pasid_features;
#endif
phys_addr_t rom; /* Physical address of ROM if it's not from the BAR */
size_t romlen; /* Length of ROM if it's not from the BAR */