From: Bjorn Helgaas <bhelgaas@google.com>
Date: Fri, 9 Sep 2022 20:24:57 +0000 (-0500)
Subject: PCI/PTM: Cache PTM Capability offset
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=a47126ec29f538e1197862919f94d3b6668144a4;p=linux.git
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 <rajvi.jingar@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c
index 368a254e31242..85382c1358852 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 060af91bafcd4..54be939023a3c 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;