[PATCH 1/1] drm/nouveau: Use generic helper to check _PR3 presence

From: Kai-Heng Feng
Date: Thu Apr 23 2020 - 02:24:20 EST


Replace nouveau_pr3_present() in favor of a more generic one,
pci_pr3_present().

Also the presence of upstream bridge _PR3 doesn't need to go hand in
hand with device's _DSM, so check _PR3 before _DSM.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
---
drivers/gpu/drm/nouveau/nouveau_acpi.c | 44 ++++++--------------------
1 file changed, 10 insertions(+), 34 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c
index fe3a10255c36..b84dff1b0f28 100644
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c
+++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c
@@ -212,37 +212,6 @@ static const struct vga_switcheroo_handler nouveau_dsm_handler = {
.get_client_id = nouveau_dsm_get_client_id,
};

-/*
- * Firmware supporting Windows 8 or later do not use _DSM to put the device into
- * D3cold, they instead rely on disabling power resources on the parent.
- */
-static bool nouveau_pr3_present(struct pci_dev *pdev)
-{
- struct pci_dev *parent_pdev = pci_upstream_bridge(pdev);
- struct acpi_device *parent_adev;
-
- if (!parent_pdev)
- return false;
-
- if (!parent_pdev->bridge_d3) {
- /*
- * Parent PCI bridge is currently not power managed.
- * Since userspace can change these afterwards to be on
- * the safe side we stick with _DSM and prevent usage of
- * _PR3 from the bridge.
- */
- pci_d3cold_disable(pdev);
- return false;
- }
-
- parent_adev = ACPI_COMPANION(&parent_pdev->dev);
- if (!parent_adev)
- return false;
-
- return parent_adev->power.flags.power_resources &&
- acpi_has_method(parent_adev->handle, "_PR3");
-}
-
static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out,
bool *has_mux, bool *has_opt,
bool *has_opt_flags, bool *has_pr3)
@@ -250,6 +219,16 @@ static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out
acpi_handle dhandle;
bool supports_mux;
int optimus_funcs;
+ struct pci_dev *parent_pdev;
+
+ *has_pr3 = false;
+ parent_pdev = pci_upstream_bridge(pdev);
+ if (parent_pdev) {
+ if (parent_pdev->bridge_d3)
+ *has_pr3 = pci_pr3_present(parent_pdev);
+ else
+ pci_d3cold_disable(pdev);
+ }

dhandle = ACPI_HANDLE(&pdev->dev);
if (!dhandle)
@@ -270,7 +249,6 @@ static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out
*has_mux = supports_mux;
*has_opt = !!optimus_funcs;
*has_opt_flags = optimus_funcs & (1 << NOUVEAU_DSM_OPTIMUS_FLAGS);
- *has_pr3 = false;

if (optimus_funcs) {
uint32_t result;
@@ -280,8 +258,6 @@ static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out
(result & OPTIMUS_ENABLED) ? "enabled" : "disabled",
(result & OPTIMUS_DYNAMIC_PWR_CAP) ? "dynamic power, " : "",
(result & OPTIMUS_HDA_CODEC_MASK) ? "hda bios codec supported" : "");
-
- *has_pr3 = nouveau_pr3_present(pdev);
}
}

--
2.17.1