Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-20 07:09:58 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

PCI/ASPM: Move pci_configure_ltr() to aspm.c

Browse Source 
The Latency Tolerance Reporting (LTR) mechanism supports the ASPM L1.2
state and is only configured when CONFIG_PCIEASPM is set.

Move pci_configure_ltr() and pci_bridge_reconfigure_ltr() into aspm.c since
they only build when CONFIG_PCIEASPM is set.  No functional change
intended.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20240128233212.1139663-2-david.e.box@linux.intel.com
[bhelgaas: commit log, split build change from function moves]
Link: https://lore.kernel.org/r/20240223205851.114931-2-helgaas@kernel.org
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
David E. Box 2024-02-23 14:58:47 -06:00 committed by Bjorn Helgaas
parent 6613476e22
commit fa84f4435a
4 changed files with 79 additions and 80 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
drivers/pci/pci.c
View File

@ -1626,24 +1626,6 @@ static int pci_save_pcie_state(struct pci_dev *dev)
return 0;
}
void pci_bridge_reconfigure_ltr(struct pci_dev *dev)
{
#ifdef CONFIG_PCIEASPM
struct pci_dev *bridge;
u32 ctl;
bridge = pci_upstream_bridge(dev);
if (bridge && bridge->ltr_path) {
pcie_capability_read_dword(bridge, PCI_EXP_DEVCTL2, &ctl);
if (!(ctl & PCI_EXP_DEVCTL2_LTR_EN)) {
pci_dbg(bridge, "re-enabling LTR\n");
pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
PCI_EXP_DEVCTL2_LTR_EN);
}
}
#endif
}
static void pci_restore_pcie_state(struct pci_dev *dev)
{
int i = 0;

5
drivers/pci/pci.h
View File

@ -97,7 +97,6 @@ void pci_msi_init(struct pci_dev *dev);
void pci_msix_init(struct pci_dev *dev);
bool pci_bridge_d3_possible(struct pci_dev *dev);
void pci_bridge_d3_update(struct pci_dev *dev);
void pci_bridge_reconfigure_ltr(struct pci_dev *dev);
int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type);
static inline void pci_wakeup_event(struct pci_dev *dev)
@ -573,11 +572,15 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev);
void pcie_aspm_exit_link_state(struct pci_dev *pdev);
void pcie_aspm_pm_state_change(struct pci_dev *pdev);
void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
void pci_configure_ltr(struct pci_dev *pdev);
void pci_bridge_reconfigure_ltr(struct pci_dev *pdev);
#else
static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { }
static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { }
static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
static inline void pci_configure_ltr(struct pci_dev *pdev) { }
static inline void pci_bridge_reconfigure_ltr(struct pci_dev *pdev) { }
#endif
#ifdef CONFIG_PCIE_ECRC

75
drivers/pci/pcie/aspm.c
View File

@ -938,6 +938,81 @@ out:
up_read(&pci_bus_sem);
}
void pci_bridge_reconfigure_ltr(struct pci_dev *pdev)
{
struct pci_dev *bridge;
u32 ctl;
bridge = pci_upstream_bridge(pdev);
if (bridge && bridge->ltr_path) {
pcie_capability_read_dword(bridge, PCI_EXP_DEVCTL2, &ctl);
if (!(ctl & PCI_EXP_DEVCTL2_LTR_EN)) {
pci_dbg(bridge, "re-enabling LTR\n");
pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
PCI_EXP_DEVCTL2_LTR_EN);
}
}
}
void pci_configure_ltr(struct pci_dev *pdev)
{
struct pci_host_bridge *host = pci_find_host_bridge(pdev->bus);
struct pci_dev *bridge;
u32 cap, ctl;
if (!pci_is_pcie(pdev))
return;
/* Read L1 PM substate capabilities */
pdev->l1ss = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_L1SS);
pcie_capability_read_dword(pdev, PCI_EXP_DEVCAP2, &cap);
if (!(cap & PCI_EXP_DEVCAP2_LTR))
return;
pcie_capability_read_dword(pdev, PCI_EXP_DEVCTL2, &ctl);
if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT) {
pdev->ltr_path = 1;
return;
}
bridge = pci_upstream_bridge(pdev);
if (bridge && bridge->ltr_path)
pdev->ltr_path = 1;
return;
}
if (!host->native_ltr)
return;
/*
* Software must not enable LTR in an Endpoint unless the Root
* Complex and all intermediate Switches indicate support for LTR.
* PCIe r4.0, sec 6.18.
*/
if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT) {
pcie_capability_set_word(pdev, PCI_EXP_DEVCTL2,
PCI_EXP_DEVCTL2_LTR_EN);
pdev->ltr_path = 1;
return;
}
/*
* If we're configuring a hot-added device, LTR was likely
* disabled in the upstream bridge, so re-enable it before enabling
* it in the new device.
*/
bridge = pci_upstream_bridge(pdev);
if (bridge && bridge->ltr_path) {
pci_bridge_reconfigure_ltr(pdev);
pcie_capability_set_word(pdev, PCI_EXP_DEVCTL2,
PCI_EXP_DEVCTL2_LTR_EN);
pdev->ltr_path = 1;
}
}
/* Recheck latencies and update aspm_capable for links under the root */
static void pcie_update_aspm_capable(struct pcie_link_state *root)
{

61
drivers/pci/probe.c
View File

@ -2209,67 +2209,6 @@ static void pci_configure_relaxed_ordering(struct pci_dev *dev)
}
}
static void pci_configure_ltr(struct pci_dev *dev)
{
#ifdef CONFIG_PCIEASPM
struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
struct pci_dev *bridge;
u32 cap, ctl;
if (!pci_is_pcie(dev))
return;
/* Read L1 PM substate capabilities */
dev->l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS);
pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
if (!(cap & PCI_EXP_DEVCAP2_LTR))
return;
pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl);
if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
dev->ltr_path = 1;
return;
}
bridge = pci_upstream_bridge(dev);
if (bridge && bridge->ltr_path)
dev->ltr_path = 1;
return;
}
if (!host->native_ltr)
return;
/*
* Software must not enable LTR in an Endpoint unless the Root
* Complex and all intermediate Switches indicate support for LTR.
* PCIe r4.0, sec 6.18.
*/
if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
PCI_EXP_DEVCTL2_LTR_EN);
dev->ltr_path = 1;
return;
}
/*
* If we're configuring a hot-added device, LTR was likely
* disabled in the upstream bridge, so re-enable it before enabling
* it in the new device.
*/
bridge = pci_upstream_bridge(dev);
if (bridge && bridge->ltr_path) {
pci_bridge_reconfigure_ltr(dev);
pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
PCI_EXP_DEVCTL2_LTR_EN);
dev->ltr_path = 1;
}
#endif
}
static void pci_configure_eetlp_prefix(struct pci_dev *dev)
{
#ifdef CONFIG_PCI_PASID