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| author |   CQ Tang <cq.tang@intel.com> | 2017-05-30 09:25:49 -0700 |
|---|---|---|
| committer |   Bjorn Helgaas <bhelgaas@google.com> | 2017-05-30 15:40:50 -0500 |
| commit | 4ebeb1ec56d4c54a56b6f43c2603d9a4688c83ba (patch) | |
| tree | 8d5adc040423e0c4bd7374a4f4679c8e238f337b /drivers/pci/ats.c | |
| parent | PCI: Cache PRI and PASID bits in pci_dev (diff) | |
| download | linux-dev-4ebeb1ec56d4c54a56b6f43c2603d9a4688c83ba.tar.xz linux-dev-4ebeb1ec56d4c54a56b6f43c2603d9a4688c83ba.zip | |
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>
Diffstat (limited to 'drivers/pci/ats.c')
| -rw-r--r-- | drivers/pci/ats.c | 64 |
1 files changed, 48 insertions, 16 deletions
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c index 21264976fa13..ad8ddbbbf245 100644 --- a/drivers/pci/ats.c +++ b/drivers/pci/ats.c @@ -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; @@ -206,6 +205,28 @@ 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) { @@ -305,6 +316,27 @@ 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 * |