This patch reorganizes negotiate_os_control() to be less ASPM-centric in
order to:
1. allow other features (notably AER) to work without enabling ASPM
2. better isolate feature-specific tests for readability/maintenance
Each feature (ASPM, PCIe hotplug, SHPC hotplug, and AER) now has its own
inline function for setting its _OSC control requests.
Part of making this function more generic, required eliminating a test
for overall success/failure that previously caused two different types
of messages to be printed. Now, printed messages are streamlined to
always show requested _OSC control versus what was granted.
Previous output (success):
acpi PNP0A08:00: _OSC: OS now controls [PME AER PCIeCapability LTR]
Previous output (failure):
acpi PNP0A08:00: _OSC: OS requested [PME AER PCIeCapability LTR]
acpi PNP0A08:00: _OSC: platform willing to grant []
New output:
acpi PNP0A08:00: _OSC: OS requested [PME AER PCIeCapability LTR]
acpi PNP0A08:00: _OSC: platform granted [PME AER PCIeCapability LTR]
Signed-off-by: Aaron Sierra <asierra@xxxxxxxxxxx>
---
v3:
* Dropped patch moving the pcie_ports_disabled check
* Removed underscore prefix from new inline functions
* Defined ASPM_OSC_CONTROL_BITS and removed __osc_have_aspm_control()
* Refactored OSC control bit-setting functions to return the bits they want
to set, instead of an ignored error code, and converted most conditionals
from inverted logic, (!x || !y), to positive logic, (x && y)
* Renamed OSC control bit-setting functions from __osc_set_X_control()
to osc_get_X_control_bits()
v2:
* Rebased from the mainline kernel (4.19-rc7) to Bjorn Helgaas's
pci/aspm branch [1]
* Factored moving the pcie_ports_disabled check to the top of
negotiate_os_control into its own patch
* Simplified new __osc_check_support function and renamed it to
__osc_have_support
* No longer messes with _OSC general availability test and related
error message (i.e. _OSC failed ... disabling ASPM)
[1] https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git
drivers/acpi/pci_root.c | 111 ++++++++++++++++++++++++++++++----------
1 file changed, 83 insertions(+), 28 deletions(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 707aafc7c2aa..ac74bd42399d 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -53,9 +53,13 @@ static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
}
#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
- | OSC_PCI_ASPM_SUPPORT \
- | OSC_PCI_CLOCK_PM_SUPPORT \
| OSC_PCI_MSI_SUPPORT)
+#define ACPI_PCIE_ASPM_SUPPORT (ACPI_PCIE_REQ_SUPPORT \
+ | OSC_PCI_ASPM_SUPPORT \
+ | OSC_PCI_CLOCK_PM_SUPPORT)
+#define OSC_CONTROL_BITS_ASPM (OSC_PCI_EXPRESS_CAPABILITY_CONTROL \
+ | OSC_PCI_EXPRESS_LTR_CONTROL \
+ | OSC_PCI_EXPRESS_PME_CONTROL)
static const struct acpi_device_id root_device_ids[] = {
{"PNP0A03", 0},
@@ -421,6 +425,67 @@ acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
}
EXPORT_SYMBOL(acpi_pci_osc_control_set);
+static inline bool osc_have_support(u32 support, u32 required)
+{
+ return ((support & required) == required);
+}
+
+static inline u32 osc_get_aspm_control_bits(struct acpi_pci_root *root,
+ u32 support)
+{
+ u32 control = 0;
+
+ if (IS_ENABLED(CONFIG_PCIEASPM) &&
+ osc_have_support(support, ACPI_PCIE_ASPM_SUPPORT)) {
+ control = OSC_CONTROL_BITS_ASPM;
+ }
+
+ return control;
+}
+
+static inline u32 osc_get_pciehp_control_bits(struct acpi_pci_root *root,
+ u32 support)
+{
+ u32 control = 0;
+
+ if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE) &&
+ osc_have_support(support, ACPI_PCIE_REQ_SUPPORT)) {
+ control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL |
+ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
+ }
+
+ return control;
+}
+
+static inline u32 osc_get_shpchp_control_bits(struct acpi_pci_root *root,
+ u32 support)
+{
+ u32 control = 0;
+
+ if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC) &&
+ osc_have_support(support, ACPI_PCIE_REQ_SUPPORT)) {
+ control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL |
+ OSC_PCI_SHPC_NATIVE_HP_CONTROL;
+ }
+
+ return control;
+}
+
+static inline u32 osc_get_aer_control_bits(struct acpi_pci_root *root,
+ u32 support)
+{
+ if (!pci_aer_available() ||
+ !osc_have_support(support, ACPI_PCIE_REQ_SUPPORT))
+ return 0;
+
+ if (aer_acpi_firmware_first()) {
+ dev_info(&root->device->dev, "PCIe AER handled by firmware\n");
+ return 0;
+ }
+
+ return OSC_PCI_EXPRESS_CAPABILITY_CONTROL | OSC_PCI_EXPRESS_AER_CONTROL;
+}
+
static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
bool is_pcie)
{
@@ -479,31 +544,24 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
return;
}
- control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
- | OSC_PCI_EXPRESS_PME_CONTROL;
-
- if (IS_ENABLED(CONFIG_PCIEASPM))
- control |= OSC_PCI_EXPRESS_LTR_CONTROL;
-
- if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
- control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
-
- if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
- control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
+ control = osc_get_aspm_control_bits(root, support);
+ if (!control)
+ *no_aspm = 1;
- if (pci_aer_available()) {
- if (aer_acpi_firmware_first())
- dev_info(&device->dev,
- "PCIe AER handled by firmware\n");
- else
- control |= OSC_PCI_EXPRESS_AER_CONTROL;
+ control |= osc_get_pciehp_control_bits(root, support);
+ control |= osc_get_shpchp_control_bits(root, support);
+ control |= osc_get_aer_control_bits(root, support);
+ if (!control) {
+ dev_info(&device->dev, "_OSC: not requesting OS control\n");
+ return;
}
requested = control;
- status = acpi_pci_osc_control_set(handle, &control,
- OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
- if (ACPI_SUCCESS(status)) {
- decode_osc_control(root, "OS now controls", control);
+ acpi_pci_osc_control_set(handle, &control, 0);
+ decode_osc_control(root, "OS requested", requested);
+ decode_osc_control(root, "platform granted", control);
+
+ if (osc_have_support(control, OSC_CONTROL_BITS_ASPM)) {
if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
/*
* We have ASPM control, but the FADT indicates that
@@ -513,11 +571,8 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
*no_aspm = 1;
}
- } else {
- decode_osc_control(root, "OS requested", requested);
- decode_osc_control(root, "platform willing to grant", control);
- dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
- acpi_format_exception(status));
+ } else if (!*no_aspm) {
+ dev_info(&device->dev, "_OSC failed; disabling ASPM\n");
/*
* We want to disable ASPM here, but aspm_disabled
--
2.17.1
