| Message ID | 20250227170012.124768-7-marex@denx.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | arm64: dts: imx95: Add support for Mali G310 GPU | expand |
On Thu, 27 Feb 2025 17:58:06 +0100 Marek Vasut <marex@denx.de> wrote: > This seems necessary on Freescale i.MX95 Mali G310 to reliably resume > from runtime PM suspend. Without this, if only the L2 is powered down > on RPM entry, the GPU gets stuck and does not indicate the firmware is > booted after RPM resume. > > Signed-off-by: Marek Vasut <marex@denx.de> > --- > Cc: Boris Brezillon <boris.brezillon@collabora.com> > Cc: Conor Dooley <conor+dt@kernel.org> > Cc: David Airlie <airlied@gmail.com> > Cc: Fabio Estevam <festevam@gmail.com> > Cc: Krzysztof Kozlowski <krzk+dt@kernel.org> > Cc: Liviu Dudau <liviu.dudau@arm.com> > Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> > Cc: Maxime Ripard <mripard@kernel.org> > Cc: Pengutronix Kernel Team <kernel@pengutronix.de> > Cc: Philipp Zabel <p.zabel@pengutronix.de> > Cc: Rob Herring <robh@kernel.org> > Cc: Sascha Hauer <s.hauer@pengutronix.de> > Cc: Sebastian Reichel <sre@kernel.org> > Cc: Shawn Guo <shawnguo@kernel.org> > Cc: Simona Vetter <simona@ffwll.ch> > Cc: Steven Price <steven.price@arm.com> > Cc: Thomas Zimmermann <tzimmermann@suse.de> > Cc: devicetree@vger.kernel.org > Cc: dri-devel@lists.freedesktop.org > Cc: imx@lists.linux.dev > Cc: linux-arm-kernel@lists.infradead.org > --- > drivers/gpu/drm/panthor/panthor_gpu.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c > index 671049020afaa..0f07ef7d9aea7 100644 > --- a/drivers/gpu/drm/panthor/panthor_gpu.c > +++ b/drivers/gpu/drm/panthor/panthor_gpu.c > @@ -470,11 +470,12 @@ int panthor_gpu_soft_reset(struct panthor_device *ptdev) > */ > void panthor_gpu_suspend(struct panthor_device *ptdev) > { > - /* On a fast reset, simply power down the L2. */ > - if (!ptdev->reset.fast) > - panthor_gpu_soft_reset(ptdev); > - else > - panthor_gpu_power_off(ptdev, L2, 1, 20000); > + /* > + * Power off the L2 and soft reset the GPU, that makes > + * iMX95 Mali G310 resume without firmware boot timeout. > + */ > + panthor_gpu_power_off(ptdev, L2, 1, 20000); > + panthor_gpu_soft_reset(ptdev); Unfortunately, if you do that unconditionally we no longer have a fast-reset. Would be good to figure out why the fast-reset doesn't work on this platform.
On 2/27/25 6:17 PM, Boris Brezillon wrote: [...] >> diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c >> index 671049020afaa..0f07ef7d9aea7 100644 >> --- a/drivers/gpu/drm/panthor/panthor_gpu.c >> +++ b/drivers/gpu/drm/panthor/panthor_gpu.c >> @@ -470,11 +470,12 @@ int panthor_gpu_soft_reset(struct panthor_device *ptdev) >> */ >> void panthor_gpu_suspend(struct panthor_device *ptdev) >> { >> - /* On a fast reset, simply power down the L2. */ >> - if (!ptdev->reset.fast) >> - panthor_gpu_soft_reset(ptdev); >> - else >> - panthor_gpu_power_off(ptdev, L2, 1, 20000); >> + /* >> + * Power off the L2 and soft reset the GPU, that makes >> + * iMX95 Mali G310 resume without firmware boot timeout. >> + */ >> + panthor_gpu_power_off(ptdev, L2, 1, 20000); >> + panthor_gpu_soft_reset(ptdev); > > Unfortunately, if you do that unconditionally we no longer have a > fast-reset. Would be good to figure out why the fast-reset doesn't work > on this platform. I was hoping to get some hint on this one, I spent quite a while trying to narrow this down, finally got it down to this particular bit. The NXP downstream vendor kernel vendor Mali driver does not seem to have anything interesting regarding the L2 power handling, but I might have missed it, the code is difficult to read. Have you ever seen anything problematic in this specific L2 department ? Do you have any hints how I can debug this further ?
diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c index 671049020afaa..0f07ef7d9aea7 100644 --- a/drivers/gpu/drm/panthor/panthor_gpu.c +++ b/drivers/gpu/drm/panthor/panthor_gpu.c @@ -470,11 +470,12 @@ int panthor_gpu_soft_reset(struct panthor_device *ptdev) */ void panthor_gpu_suspend(struct panthor_device *ptdev) { - /* On a fast reset, simply power down the L2. */ - if (!ptdev->reset.fast) - panthor_gpu_soft_reset(ptdev); - else - panthor_gpu_power_off(ptdev, L2, 1, 20000); + /* + * Power off the L2 and soft reset the GPU, that makes + * iMX95 Mali G310 resume without firmware boot timeout. + */ + panthor_gpu_power_off(ptdev, L2, 1, 20000); + panthor_gpu_soft_reset(ptdev); panthor_gpu_irq_suspend(&ptdev->gpu->irq); }
This seems necessary on Freescale i.MX95 Mali G310 to reliably resume from runtime PM suspend. Without this, if only the L2 is powered down on RPM entry, the GPU gets stuck and does not indicate the firmware is booted after RPM resume. Signed-off-by: Marek Vasut <marex@denx.de> --- Cc: Boris Brezillon <boris.brezillon@collabora.com> Cc: Conor Dooley <conor+dt@kernel.org> Cc: David Airlie <airlied@gmail.com> Cc: Fabio Estevam <festevam@gmail.com> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Rob Herring <robh@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Sebastian Reichel <sre@kernel.org> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Simona Vetter <simona@ffwll.ch> Cc: Steven Price <steven.price@arm.com> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: devicetree@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: imx@lists.linux.dev Cc: linux-arm-kernel@lists.infradead.org --- drivers/gpu/drm/panthor/panthor_gpu.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)