From a47126ec29f538e1197862919f94d3b6668144a4 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 9 Sep 2022 15:24:57 -0500 Subject: [PATCH] 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 --- drivers/pci/pcie/ptm.c | 41 +++++++++++++++++------------------------ include/linux/pci.h | 1 + 2 files changed, 18 insertions(+), 24 deletions(-) diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c index 368a254..85382c1 100644 --- a/drivers/pci/pcie/ptm.c +++ b/drivers/pci/pcie/ptm.c @@ -31,13 +31,9 @@ static void pci_ptm_info(struct pci_dev *dev) void pci_disable_ptm(struct pci_dev *dev) { - int ptm; + u16 ptm = dev->ptm_cap; u16 ctrl; - if (!pci_is_pcie(dev)) - return; - - ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM); if (!ptm) return; @@ -48,14 +44,10 @@ void pci_disable_ptm(struct pci_dev *dev) void pci_save_ptm_state(struct pci_dev *dev) { - int ptm; + u16 ptm = dev->ptm_cap; struct pci_cap_saved_state *save_state; u16 *cap; - if (!pci_is_pcie(dev)) - return; - - ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM); if (!ptm) return; @@ -69,16 +61,15 @@ void pci_save_ptm_state(struct pci_dev *dev) void pci_restore_ptm_state(struct pci_dev *dev) { + u16 ptm = dev->ptm_cap; struct pci_cap_saved_state *save_state; - int ptm; u16 *cap; - if (!pci_is_pcie(dev)) + if (!ptm) return; save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_PTM); - ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM); - if (!save_state || !ptm) + if (!save_state) return; cap = (u16 *)&save_state->cap.data[0]; @@ -87,7 +78,7 @@ void pci_restore_ptm_state(struct pci_dev *dev) void pci_ptm_init(struct pci_dev *dev) { - int pos; + u16 ptm; u32 cap, ctrl; u8 local_clock; struct pci_dev *ups; @@ -117,13 +108,14 @@ void pci_ptm_init(struct pci_dev *dev) return; } - pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM); - if (!pos) + ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM); + if (!ptm) return; + dev->ptm_cap = ptm; pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_PTM, sizeof(u16)); - pci_read_config_dword(dev, pos + PCI_PTM_CAP, &cap); + pci_read_config_dword(dev, ptm + PCI_PTM_CAP, &cap); local_clock = (cap & PCI_PTM_GRANULARITY_MASK) >> 8; /* @@ -148,7 +140,7 @@ void pci_ptm_init(struct pci_dev *dev) } ctrl |= dev->ptm_granularity << 8; - pci_write_config_dword(dev, pos + PCI_PTM_CTRL, ctrl); + pci_write_config_dword(dev, ptm + PCI_PTM_CTRL, ctrl); dev->ptm_enabled = 1; pci_ptm_info(dev); @@ -156,18 +148,19 @@ void pci_ptm_init(struct pci_dev *dev) int pci_enable_ptm(struct pci_dev *dev, u8 *granularity) { - int pos; + u16 ptm; u32 cap, ctrl; struct pci_dev *ups; if (!pci_is_pcie(dev)) return -EINVAL; - pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM); - if (!pos) + ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM); + if (!ptm) return -EINVAL; - pci_read_config_dword(dev, pos + PCI_PTM_CAP, &cap); + dev->ptm_cap = ptm; + pci_read_config_dword(dev, ptm + PCI_PTM_CAP, &cap); if (!(cap & PCI_PTM_CAP_REQ)) return -EINVAL; @@ -192,7 +185,7 @@ int pci_enable_ptm(struct pci_dev *dev, u8 *granularity) ctrl = PCI_PTM_CTRL_ENABLE; ctrl |= dev->ptm_granularity << 8; - pci_write_config_dword(dev, pos + PCI_PTM_CTRL, ctrl); + pci_write_config_dword(dev, ptm + PCI_PTM_CTRL, ctrl); dev->ptm_enabled = 1; pci_ptm_info(dev); diff --git a/include/linux/pci.h b/include/linux/pci.h index 060af91..54be939 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; -- 2.7.4