| Message ID | 20220906222351.64760-3-helgaas@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | PCI/PM: Always disable PTM for all devices during suspend | expand |
Hi, On 9/6/22 3:23 PM, Bjorn Helgaas wrote: > From: Bjorn Helgaas <bhelgaas@google.com> > > Cache the PTM Capability offset instead of searching for it every time we > enable/disable PTM or save/restore PTM state. > > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> > --- > 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 b6a417247ce3..6ac7ff48be57 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; > + int ptm = dev->ptm_cap; I think you don't need to store it. Directly use dev->ptm? > 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; > + int ptm = dev->ptm_cap; Same as above. > 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) > { > + int ptm = dev->ptm_cap; It can be u16? > 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; > + int ptm; Why rename? Also ptm can be u16 > 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; > + int 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 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;
On Tue, Sep 06, 2022 at 04:18:23PM -0700, Sathyanarayanan Kuppuswamy wrote: > On 9/6/22 3:23 PM, Bjorn Helgaas wrote: > > void pci_disable_ptm(struct pci_dev *dev) > > { > > - int ptm; > > + int ptm = dev->ptm_cap; > > I think you don't need to store it. Directly use dev->ptm? True, no need, but the value is used three times in this function, so I think the variable reduces clutter overall. > > void pci_restore_ptm_state(struct pci_dev *dev) > > { > > + int ptm = dev->ptm_cap; > > It can be u16? Done, thanks! I see that in ee8b1c478a9f ("PCI: Return u16 from pci_find_ext_capability() and similar"), I forgot to change the inline stub from int to u16. I'll add a patch to do that. Probably not a prerequisite, since the stub is for !CONFIG_PCI and this code won't be compiled at all in that case. > > void pci_ptm_init(struct pci_dev *dev) > > { > > - int pos; > > + int ptm; > > Why rename? Also ptm can be u16 "ptm" conveys more information than "pos" and I think it's worth using the same name for all the functions. Thank you! Bjorn
diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c index b6a417247ce3..6ac7ff48be57 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; + int 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; + int 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) { + int 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; + int 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; + int 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 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;