[PATCH v1] PCI: enable ASPM configuration in PCIE POWERSAVE mode

From: Vidya Sagar
Date: Tue Jul 01 2014 - 03:17:22 EST


commit 1a680b7c moved pcie_aspm_powersave_config_link() out of
pci_raw_set_power_state() to pci_set_power_state() which would enable
ASPM. But, with commit db288c9c, which re-introduced the following check
./drivers/pci/pci.c: pci_set_power_state()
+ /* Check if we're already there */
+ if (dev->current_state == state)
+ return 0;
in pci_set_power_state(), call to pcie_aspm_powersave_config_link() is never
made leaving ASPM broken.
Fix it by not returning from when the above condition is true, rather, jump to
ASPM configuration code and exit from there eventually.

Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
---
drivers/pci/pci.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 1c8592b..ded24c4 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -804,7 +804,7 @@ EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
*/
int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
{
- int error;
+ int error = 0;

/* bound the state we're entering */
if (state > PCI_D3cold)
@@ -821,7 +821,7 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)

/* Check if we're already there */
if (dev->current_state == state)
- return 0;
+ goto config_aspm;

__pci_start_power_transition(dev, state);

@@ -839,6 +839,8 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)

if (!__pci_complete_power_transition(dev, state))
error = 0;
+
+config_aspm:
/*
* When aspm_policy is "powersave" this call ensures
* that ASPM is configured.
--
1.8.1.5

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