Hi Alex,
On 12/11/2025 9:33 AM, Alex Deucher wrote:
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On Wed, Dec 10, 2025 at 6:24 PM Nirujogi, Pratap <[email protected]> wrote:
Hi Mario,
On 12/9/2025 10:28 PM, Mario Limonciello wrote:
On 12/9/2025 7:50 PM, Pratap Nirujogi wrote:
ISP mfd child devices are using genpd and the system suspend-resume
operations between genpd and amdgpu parent device which uses only
runtime suspend-resume are not in sync.
Linux power manager during suspend-resume resuming the genpd devices
earlier than the amdgpu parent device. This is resulting in the below
warning as SMU is in suspended state when genpd attempts to resume ISP.
WARNING: CPU: 13 PID: 5435 at
drivers/gpu/drm/amd/amdgpu/../pm/swsmu/amdgpu_smu.c:398
smu_dpm_set_power_gate+0x36f/0x380 [amdgpu]
To fix this warning isp suspend-resume is handled as part of amdgpu
parent device suspend-resume instead of genpd sequence. Each ISP MFD
child device is marked as dev_pm_syscore_device to skip genpd
suspend-resume and use pm_runtime_force api's to suspend-resume
the devices when callbacks from amdgpu are received.
Signed-off-by: Gjorgji Rosikopulos <[email protected]>
Signed-off-by: Bin Du <[email protected]>
Signed-off-by: Pratap Nirujogi <[email protected]>
Who is the patch author? If you guys worked together, there should be
Co-developed-by tags to represent it.
---
drivers/gpu/drm/amd/amdgpu/amdgpu_isp.c | 24 ++++++++++
drivers/gpu/drm/amd/amdgpu/amdgpu_isp.h | 2 +
drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c | 59 +++++++++++++++++++++++++
3 files changed, 85 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.c
index 37270c4dab8d..532f83d783d1 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.c
@@ -318,12 +318,36 @@ void isp_kernel_buffer_free(void **buf_obj, u64
*gpu_addr, void **cpu_addr)
}
EXPORT_SYMBOL(isp_kernel_buffer_free);
+static int isp_resume(struct amdgpu_ip_block *ip_block)
+{
+ struct amdgpu_device *adev = ip_block->adev;
+ struct amdgpu_isp *isp = &adev->isp;
+
+ if (isp->funcs->hw_resume)
+ return isp->funcs->hw_resume(isp);
+
+ return -ENODEV;
+}
+
+static int isp_suspend(struct amdgpu_ip_block *ip_block)
+{
+ struct amdgpu_device *adev = ip_block->adev;
+ struct amdgpu_isp *isp = &adev->isp;
+
+ if (isp->funcs->hw_suspend)
+ return isp->funcs->hw_suspend(isp);
+
+ return -ENODEV;
+}
+
static const struct amd_ip_funcs isp_ip_funcs = {
.name = "isp_ip",
.early_init = isp_early_init,
.hw_init = isp_hw_init,
.hw_fini = isp_hw_fini,
.is_idle = isp_is_idle,
+ .suspend = isp_suspend,
+ .resume = isp_resume,
.set_clockgating_state = isp_set_clockgating_state,
.set_powergating_state = isp_set_powergating_state,
};
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.h
b/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.h
index d6f4ffa4c97c..9a5d2b1dff9e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_isp.h
@@ -38,6 +38,8 @@ struct amdgpu_isp;
struct isp_funcs {
int (*hw_init)(struct amdgpu_isp *isp);
int (*hw_fini)(struct amdgpu_isp *isp);
+ int (*hw_suspend)(struct amdgpu_isp *isp);
+ int (*hw_resume)(struct amdgpu_isp *isp);
};
struct amdgpu_isp {
diff --git a/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
b/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
index 4258d3e0b706..560c398e14fc 100644
--- a/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
+++ b/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
@@ -26,6 +26,7 @@
*/
#include <linux/gpio/machine.h>
+#include <linux/pm_runtime.h>
#include "amdgpu.h"
#include "isp_v4_1_1.h"
@@ -145,6 +146,9 @@ static int isp_genpd_add_device(struct device
*dev, void *data)
return -ENODEV;
}
+ /* The devcies will be managed by the pm ops from the parent */
devices
+ dev_pm_syscore_device(dev, true);
+
exit:
/* Continue to add */
return 0;
@@ -177,12 +181,65 @@ static int isp_genpd_remove_device(struct
device *dev, void *data)
drm_err(&adev->ddev, "Failed to remove dev from genpd
%d\n", ret);
return -ENODEV;
}
+ dev_pm_syscore_device(dev, false);
exit:
/* Continue to remove */
return 0;
}
+static int isp_suspend_device(struct device *dev, void *data)
+{
+ struct platform_device *pdev = container_of(dev, struct
platform_device, dev);
+
+ if (!dev->type || !dev->type->name)
+ return 0;
+ if (strncmp(dev->type->name, "mfd_device", 10))
+ return 0;
+ if (!strncmp(pdev->mfd_cell->name, "amdisp-pinctrl", 14))
+ return 0;
Could we store the mfd_cell pointer instead and just compare the
pointers?
I don't think I can do a pointer comparision to identify the correct
mfd_cell, string comparision seems like required in this case.
Its because when isp mfd child devices are created using
mfd_add_hotplug_devices(), it is not returning the pdev or mfd_cell handles
to store in the amdgpu_isp and later use in suspend/resume to compare
with incoming pdev->mfd_cell to detect the correct the device.
The mfd-core is doing a kmemdup of mfd_cells data passed to
mfd_add_hotplug_devices() to create the platform device.
https://github.com/torvalds/linux/blob/master/drivers/mfd/mfd-core.c#L163
I'm considering to add this function to check for valid isp mfd child
devices that are allowed to do suspend-resume, this can minimize the
checks, but still cannot eliminate the string comparsion, please let us
know your thoughts.
Can you do something like what was done in the acp code? See:
commit 4fce6b64ec8bcd0694f221906952d2880ed8ae31
Author: Brady Norander <[email protected]>
Date: Tue Mar 25 17:05:17 2025 -0400
drm/amdgpu: use static ids for ACP platform devs
mfd_add_hotplug_devices() assigns child platform devices with
PLATFORM_DEVID_AUTO, but the ACP machine drivers expect the platform
device names to never change. Use mfd_add_devices() instead and give
each cell a unique id.
Signed-off-by: Brady Norander <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Alex
Looks like this requirement is specific to ACP. Atleast for ISP mfd
devices, I haven't come across the strict need to create the devices
with static IDs. It works fine even on creating the devices with
PLATFORM_DEVID_AUTO (i.e. using mfd_add_hotplug_devices). Can I proceed
with current approach? I will take care of submitting a new patch if the
need araises to create the ISP mfd devices with static IDs in future.
Thanks,
Pratap
static bool is_valid_mfd_device(struct platform_device *pdev)
{
const struct mfd_cell *mc = mfd_get_cell(pdev);
if (!mc)
return false;
if (!strncmp(mc->name, "amdisp-pinctrl", 14))
return false;
return true;
}
Thanks,
Pratap
+
+ return pm_runtime_force_suspend(dev);
+}
+
+static int isp_resume_device(struct device *dev, void *data)
+{
+ struct platform_device *pdev = container_of(dev, struct
platform_device, dev);
+
+ if (!dev->type || !dev->type->name)
+ return 0;
+ if (strncmp(dev->type->name, "mfd_device", 10))
+ return 0;
+ if (!strncmp(pdev->mfd_cell->name, "amdisp-pinctrl", 14))
+ return 0;
same comment as above
+
+ return pm_runtime_force_resume(dev);
+}
+
+static int isp_v4_1_1_hw_suspend(struct amdgpu_isp *isp)
+{
+ int r;
+
+ r = device_for_each_child(isp->parent, NULL,
+ isp_suspend_device);
+ if (r)
+ dev_err(isp->parent, "failed to suspend hw devices (%d)\n", r);
+
+ return 0;
Shouldn't you return r?
+}
+
+static int isp_v4_1_1_hw_resume(struct amdgpu_isp *isp)
+{
+ int r;
+
+ r = device_for_each_child(isp->parent, NULL,
+ isp_resume_device);
+ if (r)
+ dev_err(isp->parent, "failed to resume hw device (%d)\n", r);
+
+ return 0;
Shouldn't you return r?
+}
+
static int isp_v4_1_1_hw_init(struct amdgpu_isp *isp)
{
const struct software_node *amd_camera_node, *isp4_node;
@@ -369,6 +426,8 @@ static int isp_v4_1_1_hw_fini(struct amdgpu_isp
*isp)
static const struct isp_funcs isp_v4_1_1_funcs = {
.hw_init = isp_v4_1_1_hw_init,
.hw_fini = isp_v4_1_1_hw_fini,
+ .hw_suspend = isp_v4_1_1_hw_suspend,
+ .hw_resume = isp_v4_1_1_hw_resume,
};
void isp_v4_1_1_set_isp_funcs(struct amdgpu_isp *isp)
