PCI: pcie: Add support for setting default ASPM policy

Distributions may wish to provide different defaults for PCIE ASPM
depending on their target audience. Provide a configuration option for
choosing the default policy.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

2 files changed, 33 insertions, 0 deletions

diff --git a/drivers/pci/pcie/Kconfig b/drivers/pci/pcie/Kconfig
index 72962cc92e0a..6c8bc5809787 100644
--- a/drivers/pci/pcie/Kconfig
+++ b/drivers/pci/pcie/Kconfig
@@ -55,6 +55,31 @@ config PCIEASPM_DEBUG
           This enables PCI Express ASPM debug support. It will add per-device
           interface to control ASPM.
 
+choice
+        prompt "Default ASPM policy"
+        default PCIEASPM_DEFAULT
+        depends on PCIEASPM
+
+config PCIEASPM_DEFAULT
+        bool "BIOS default"
+        depends on PCIEASPM
+        help
+          Use the BIOS defaults for PCI Express ASPM.
+
+config PCIEASPM_POWERSAVE
+        bool "Powersave"
+        depends on PCIEASPM
+        help
+          Enable PCI Express ASPM L0s and L1 where possible, even if the
+          BIOS did not.
+
+config PCIEASPM_PERFORMANCE
+        bool "Performance"
+        depends on PCIEASPM
+        help
+          Disable PCI Express ASPM L0s and L1, even if the BIOS enabled them.
+endchoice
+
 config PCIE_PME
         def_bool y
         depends on PCIEPORTBUS && PM_RUNTIME && EXPERIMENTAL && ACPI
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 1cfbf228fbb1..a0de5e123046 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -76,7 +76,15 @@ static LIST_HEAD(link_list);
 #define POLICY_DEFAULT 0        /* BIOS default setting */
 #define POLICY_PERFORMANCE 1    /* high performance */
 #define POLICY_POWERSAVE 2      /* high power saving */
+
+#ifdef CONFIG_PCIEASPM_PERFORMANCE
+static int aspm_policy = POLICY_PERFORMANCE;
+#elif defined CONFIG_PCIEASPM_POWERSAVE
+static int aspm_policy = POLICY_POWERSAVE;
+#else
 static int aspm_policy;
+#endif
+
 static const char *policy_str[] = {
         [POLICY_DEFAULT] = "default",
         [POLICY_PERFORMANCE] = "performance",