[PATCH 5.15 49/72] drm/amdgpu: disable runpm if we are the primary adapter

From: Greg Kroah-Hartman
Date: Mon Jan 10 2022 - 02:41:17 EST


From: Alex Deucher <alexander.deucher@xxxxxxx>

commit b95dc06af3e683d6b7ddbbae178b2b2a21ee8b2b upstream.

If we are the primary adapter (i.e., the one used by the firwmare
framebuffer), disable runtime pm. This fixes a regression caused
by commit 55285e21f045 which results in the displays waking up
shortly after they go to sleep due to the device coming out of
runtime suspend and sending a hotplug uevent.

v2: squash in reworked fix from Evan

Fixes: 55285e21f045 ("fbdev/efifb: Release PCI device's runtime PM ref during FB destroy")
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=215203
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1840
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 +
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 28 ++++++++++++++++++++++++++++
drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 6 ++++++
3 files changed, 35 insertions(+)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -1069,6 +1069,7 @@ struct amdgpu_device {
bool runpm;
bool in_runpm;
bool has_pr3;
+ bool is_fw_fb;

bool pm_sysfs_en;
bool ucode_sysfs_en;
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -38,6 +38,7 @@
#include <drm/drm_probe_helper.h>
#include <linux/mmu_notifier.h>
#include <linux/suspend.h>
+#include <linux/fb.h>

#include "amdgpu.h"
#include "amdgpu_irq.h"
@@ -1246,6 +1247,26 @@ MODULE_DEVICE_TABLE(pci, pciidlist);

static const struct drm_driver amdgpu_kms_driver;

+static bool amdgpu_is_fw_framebuffer(resource_size_t base,
+ resource_size_t size)
+{
+ bool found = false;
+#if IS_REACHABLE(CONFIG_FB)
+ struct apertures_struct *a;
+
+ a = alloc_apertures(1);
+ if (!a)
+ return false;
+
+ a->ranges[0].base = base;
+ a->ranges[0].size = size;
+
+ found = is_firmware_framebuffer(a);
+ kfree(a);
+#endif
+ return found;
+}
+
static int amdgpu_pci_probe(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
@@ -1254,6 +1275,8 @@ static int amdgpu_pci_probe(struct pci_d
unsigned long flags = ent->driver_data;
int ret, retry = 0;
bool supports_atomic = false;
+ bool is_fw_fb;
+ resource_size_t base, size;

if (amdgpu_virtual_display ||
amdgpu_device_asic_has_dc_support(flags & AMD_ASIC_MASK))
@@ -1310,6 +1333,10 @@ static int amdgpu_pci_probe(struct pci_d
}
#endif

+ base = pci_resource_start(pdev, 0);
+ size = pci_resource_len(pdev, 0);
+ is_fw_fb = amdgpu_is_fw_framebuffer(base, size);
+
/* Get rid of things like offb */
ret = drm_aperture_remove_conflicting_pci_framebuffers(pdev, &amdgpu_kms_driver);
if (ret)
@@ -1322,6 +1349,7 @@ static int amdgpu_pci_probe(struct pci_d
adev->dev = &pdev->dev;
adev->pdev = pdev;
ddev = adev_to_drm(adev);
+ adev->is_fw_fb = is_fw_fb;

if (!supports_atomic)
ddev->driver_features &= ~DRIVER_ATOMIC;
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -206,6 +206,12 @@ int amdgpu_driver_load_kms(struct amdgpu
adev->runpm = true;
break;
}
+ /* XXX: disable runtime pm if we are the primary adapter
+ * to avoid displays being re-enabled after DPMS.
+ * This needs to be sorted out and fixed properly.
+ */
+ if (adev->is_fw_fb)
+ adev->runpm = false;
if (adev->runpm)
dev_info(adev->dev, "Using BACO for runtime pm\n");
}