From 4ebeb1ec56d4c54a56b6f43c2603d9a4688c83ba Mon Sep 17 00:00:00 2001 From: CQ Tang Date: Tue, 30 May 2017 09:25:49 -0700 Subject: [PATCH] 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 Signed-off-by: Ashok Raj Signed-off-by: Bjorn Helgaas Cc: Joerg Roedel Cc: Jean-Phillipe Brucker Cc: David Woodhouse --- drivers/pci/ats.c | 64 ++++++++++++++++++++++++++++++----------- drivers/pci/pci.c | 3 ++ include/linux/pci-ats.h | 10 +++++++ include/linux/pci.h | 6 ++++ 4 files changed, 67 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; @@ -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 diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b01bd5bba8e6..3b38e98e68df 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include #include @@ -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); diff --git a/include/linux/pci-ats.h b/include/linux/pci-ats.h index 57e0b8250947..782fb8e0755f 100644 --- a/include/linux/pci-ats.h +++ b/include/linux/pci-ats.h @@ -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; diff --git a/include/linux/pci.h b/include/linux/pci.h index f612c1d85863..c7cfdff2529c 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -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 */ -- 2.20.1