From a47126ec29f538e1197862919f94d3b6668144a4 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 9 Sep 2022 15:24:57 -0500 Subject: PCI/PTM: Cache PTM Capability offset Cache the PTM Capability offset instead of searching for it every time we enable/disable PTM or save/restore PTM state. No functional change intended. Link: https://lore.kernel.org/r/20220909202505.314195-2-helgaas@kernel.org Tested-by: Rajvi Jingar Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan Reviewed-by: Mika Westerberg --- include/linux/pci.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/pci.h b/include/linux/pci.h index 060af91bafcd..54be939023a3 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -475,6 +475,7 @@ struct pci_dev { unsigned int broken_cmd_compl:1; /* No compl for some cmds */ #endif #ifdef CONFIG_PCIE_PTM + u16 ptm_cap; /* PTM Capability */ unsigned int ptm_root:1; unsigned int ptm_enabled:1; u8 ptm_granularity; -- cgit From e8bdc5ea481638e0a4fd5639050d2b170417f493 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 9 Sep 2022 15:25:00 -0500 Subject: PCI/PTM: Add pci_suspend_ptm() and pci_resume_ptm() We disable PTM during suspend because that allows some Root Ports to enter lower-power PM states, which means we also need to disable PTM for all downstream devices. Add pci_suspend_ptm() and pci_resume_ptm() for this purpose. pci_enable_ptm() and pci_disable_ptm() are for drivers to use to enable or disable PTM. They use dev->ptm_enabled to keep track of whether PTM should be enabled. pci_suspend_ptm() and pci_resume_ptm() are PCI core-internal functions to temporarily disable PTM during suspend and (depending on dev->ptm_enabled) re-enable PTM during resume. Enable/disable/suspend/resume all use internal __pci_enable_ptm() and __pci_disable_ptm() functions that only update the PTM Control register. Outline: pci_enable_ptm(struct pci_dev *dev) { __pci_enable_ptm(dev); dev->ptm_enabled = 1; pci_ptm_info(dev); } pci_disable_ptm(struct pci_dev *dev) { if (dev->ptm_enabled) { __pci_disable_ptm(dev); dev->ptm_enabled = 0; } } pci_suspend_ptm(struct pci_dev *dev) { if (dev->ptm_enabled) __pci_disable_ptm(dev); } pci_resume_ptm(struct pci_dev *dev) { if (dev->ptm_enabled) __pci_enable_ptm(dev); } Nothing currently calls pci_resume_ptm(); the suspend path saves the PTM state before disabling PTM, so the PTM state restore in the resume path implicitly re-enables it. A future change will use pci_resume_ptm() to fix some problems with this approach. Link: https://lore.kernel.org/r/20220909202505.314195-5-helgaas@kernel.org Tested-by: Rajvi Jingar Signed-off-by: Bjorn Helgaas Reviewed-by: Mika Westerberg --- include/linux/pci.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/pci.h b/include/linux/pci.h index 54be939023a3..cb5f796e3319 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1678,10 +1678,12 @@ bool pci_ats_disabled(void); #ifdef CONFIG_PCIE_PTM int pci_enable_ptm(struct pci_dev *dev, u8 *granularity); +void pci_disable_ptm(struct pci_dev *dev); bool pcie_ptm_enabled(struct pci_dev *dev); #else static inline int pci_enable_ptm(struct pci_dev *dev, u8 *granularity) { return -EINVAL; } +static inline void pci_disable_ptm(struct pci_dev *dev) { } static inline bool pcie_ptm_enabled(struct pci_dev *dev) { return false; } #endif -- cgit