[PATCH v2 08/13] e1000e: Remove unreliable pci_disable_link_state{,_locked}() workaround

From: Ilpo Järvinen
Date: Mon Sep 18 2023 - 11:49:09 EST


pci_disable_link_state() and pci_disable_link_state_locked() were made
reliable regardless of ASPM CONFIG and OS being disallowed to change
ASPM states to allow drivers to rely on them working.

Remove driver working around unreliable
pci_disable_link_state{,_locked}() from e1000e driver and just call the
functions directly.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
---
drivers/net/ethernet/intel/e1000e/netdev.c | 77 +---------------------
1 file changed, 2 insertions(+), 75 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index f536c856727c..fbe468061591 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -6765,79 +6765,6 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool runtime)
return 0;
}

-/**
- * __e1000e_disable_aspm - Disable ASPM states
- * @pdev: pointer to PCI device struct
- * @state: bit-mask of ASPM states to disable
- * @locked: indication if this context holds pci_bus_sem locked.
- *
- * Some devices *must* have certain ASPM states disabled per hardware errata.
- **/
-static void __e1000e_disable_aspm(struct pci_dev *pdev, u16 state, int locked)
-{
- struct pci_dev *parent = pdev->bus->self;
- u16 aspm_dis_mask = 0;
- u16 pdev_aspmc, parent_aspmc;
-
- switch (state) {
- case PCIE_LINK_STATE_L0S:
- case PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1:
- aspm_dis_mask |= PCI_EXP_LNKCTL_ASPM_L0S;
- fallthrough; /* can't have L1 without L0s */
- case PCIE_LINK_STATE_L1:
- aspm_dis_mask |= PCI_EXP_LNKCTL_ASPM_L1;
- break;
- default:
- return;
- }
-
- pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &pdev_aspmc);
- pdev_aspmc &= PCI_EXP_LNKCTL_ASPMC;
-
- if (parent) {
- pcie_capability_read_word(parent, PCI_EXP_LNKCTL,
- &parent_aspmc);
- parent_aspmc &= PCI_EXP_LNKCTL_ASPMC;
- }
-
- /* Nothing to do if the ASPM states to be disabled already are */
- if (!(pdev_aspmc & aspm_dis_mask) &&
- (!parent || !(parent_aspmc & aspm_dis_mask)))
- return;
-
- dev_info(&pdev->dev, "Disabling ASPM %s %s\n",
- (aspm_dis_mask & pdev_aspmc & PCI_EXP_LNKCTL_ASPM_L0S) ?
- "L0s" : "",
- (aspm_dis_mask & pdev_aspmc & PCI_EXP_LNKCTL_ASPM_L1) ?
- "L1" : "");
-
-#ifdef CONFIG_PCIEASPM
- if (locked)
- pci_disable_link_state_locked(pdev, state);
- else
- pci_disable_link_state(pdev, state);
-
- /* Double-check ASPM control. If not disabled by the above, the
- * BIOS is preventing that from happening (or CONFIG_PCIEASPM is
- * not enabled); override by writing PCI config space directly.
- */
- pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &pdev_aspmc);
- pdev_aspmc &= PCI_EXP_LNKCTL_ASPMC;
-
- if (!(aspm_dis_mask & pdev_aspmc))
- return;
-#endif
-
- /* Both device and parent should have the same ASPM setting.
- * Disable ASPM in downstream component first and then upstream.
- */
- pcie_capability_clear_word(pdev, PCI_EXP_LNKCTL, aspm_dis_mask);
-
- if (parent)
- pcie_capability_clear_word(parent, PCI_EXP_LNKCTL,
- aspm_dis_mask);
-}
-
/**
* e1000e_disable_aspm - Disable ASPM states.
* @pdev: pointer to PCI device struct
@@ -6848,7 +6775,7 @@ static void __e1000e_disable_aspm(struct pci_dev *pdev, u16 state, int locked)
**/
static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state)
{
- __e1000e_disable_aspm(pdev, state, 0);
+ pci_disable_link_state(pdev, state);
}

/**
@@ -6861,7 +6788,7 @@ static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state)
**/
static void e1000e_disable_aspm_locked(struct pci_dev *pdev, u16 state)
{
- __e1000e_disable_aspm(pdev, state, 1);
+ pci_disable_link_state_locked(pdev, state);
}

static int e1000e_pm_thaw(struct device *dev)
--
2.30.2