Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
Tomas and Daniel, We got an issue here. The relationship that we try to build between I915 and mei_hdcp is as follows: * We are using the components to establish the relationship. * I915 is component master where as mei_hdcp is component. * I915 adds the component master during the module load. mei_hdcp adds the component when the driver->probe is called (on device driver binding). * I915 forces itself such that until mei_hdcp component is added I915_load wont be complete. * Similarly on complete system, if mei_hdcp component is removed, immediately I915 unregister itself and HW will be shutdown. This is completely fine when the modules are loaded and unloaded. But during suspend, mei device disappears and mei bus handles it by unbinding device and driver by calling driver->remove. This in-turn removes the component and triggers the master unbind of I915 where, I915 unregister itself. This cause the HW state mismatch during the suspend and resume. Please check the powerwell mismatch errors at CI report for v9 https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4005/igt@gem_exec_susp...@basic-s3.html More over unregistering I915 during the suspend is not expected. So how do we handle this? -Ram On 12/13/2018 9:31 AM, Ramalingam C wrote: Mei hdcp driver is designed as component slave for the I915 component master. v2: Rebased. v3: Notifier chain is adopted for cldev state update [Tomas] v4: Made static dummy functions as inline in mei_hdcp.h API for polling client device status IS_ENABLED used in header, for config status for mei_hdcp. v5: Replacing the notifier with component framework. [Daniel] v6: Rebased on the I915 comp master redesign. v7: mei_hdcp_component_registered is made static [Uma] Need for global static variable mei_cldev is removed. Signed-off-by: Ramalingam C Reviewed-by: Uma Shankar --- drivers/misc/mei/hdcp/mei_hdcp.c | 67 +--- 1 file changed, 63 insertions(+), 4 deletions(-) diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c index b22a71e8c5d7..3de1700dcc9f 100644 --- a/drivers/misc/mei/hdcp/mei_hdcp.c +++ b/drivers/misc/mei/hdcp/mei_hdcp.c @@ -23,11 +23,14 @@ #include #include #include +#include #include #include #include "mei_hdcp.h" +static bool mei_hdcp_component_registered; + /** * mei_initiate_hdcp2_session() - Initiate a Wired HDCP2.2 Tx Session in ME FW * @dev: device corresponding to the mei_cl_device @@ -691,8 +694,7 @@ mei_close_hdcp_session(struct device *dev, struct hdcp_port_data *data) return 0; } -static __attribute__((unused)) -struct i915_hdcp_component_ops mei_hdcp_ops = { +static struct i915_hdcp_component_ops mei_hdcp_ops = { .owner = THIS_MODULE, .initiate_hdcp2_session = mei_initiate_hdcp2_session, .verify_receiver_cert_prepare_km = mei_verify_receiver_cert_prepare_km, @@ -707,20 +709,77 @@ struct i915_hdcp_component_ops mei_hdcp_ops = { .close_hdcp_session = mei_close_hdcp_session, }; +static int mei_hdcp_component_bind(struct device *mei_kdev, + struct device *i915_kdev, void *data) +{ + struct i915_component_master *master_comp = data; + + dev_info(mei_kdev, "MEI HDCP comp bind\n"); + WARN_ON(master_comp->hdcp_ops); + master_comp->hdcp_ops = &mei_hdcp_ops; + master_comp->mei_dev = mei_kdev; + + return 0; +} + +static void mei_hdcp_component_unbind(struct device *mei_kdev, + struct device *i915_kdev, void *data) +{ + struct i915_component_master *master_comp = data; + + dev_info(mei_kdev, "MEI HDCP comp unbind\n"); + master_comp->hdcp_ops = NULL; + master_comp->mei_dev = NULL; +} + +static const struct component_ops mei_hdcp_component_bind_ops = { + .bind = mei_hdcp_component_bind, + .unbind = mei_hdcp_component_unbind, +}; + +static void mei_hdcp_component_init(struct device *dev) +{ + int ret; + + dev_info(dev, "MEI HDCP comp init\n"); + ret = component_add(dev, &mei_hdcp_component_bind_ops); + if (ret < 0) { + dev_err(dev, "Failed to add MEI HDCP comp (%d)\n", ret); + return; + } + + mei_hdcp_component_registered = true; +} + +static void mei_hdcp_component_cleanup(struct device *dev) +{ + if (!mei_hdcp_component_registered) + return; + + dev_info(dev, "MEI HDCP comp cleanup\n"); + component_del(dev, &mei_hdcp_component_bind_ops); + mei_hdcp_component_registered = false; +} + static int mei_hdcp_probe(struct mei_cl_device *cldev, const struct mei_cl_device_id *id) { int ret; ret = mei_cldev_enable(cldev); - if (ret < 0) + if (ret < 0) { dev_err(&cldev->dev, "mei_cldev_enable Failed. %d\n", ret); + return ret; +
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam wrote: > > Tomas and Daniel, > > We got an issue here. > > The relationship that we try to build between I915 and mei_hdcp is as follows: > > We are using the components to establish the relationship. > I915 is component master where as mei_hdcp is component. > I915 adds the component master during the module load. mei_hdcp adds the > component when the driver->probe is called (on device driver binding). > I915 forces itself such that until mei_hdcp component is added I915_load wont > be complete. > Similarly on complete system, if mei_hdcp component is removed, immediately > I915 unregister itself and HW will be shutdown. > > This is completely fine when the modules are loaded and unloaded. > > But during suspend, mei device disappears and mei bus handles it by unbinding > device and driver by calling driver->remove. > This in-turn removes the component and triggers the master unbind of I915 > where, I915 unregister itself. > This cause the HW state mismatch during the suspend and resume. > > Please check the powerwell mismatch errors at CI report for v9 > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4005/igt@gem_exec_susp...@basic-s3.html > > More over unregistering I915 during the suspend is not expected. So how do we > handle this? Bit more context from our irc discussion with Ram: I found this very surprising, since I don't know of any other subsystems where the devices get outright removed when going through a suspend/resume cycle. The device model was built to handle this stuff correctly: First clients/devices/interfaces get suspend, then the parent/bridge/bus. Same dance in reverse when resuming. This even holds for lots of hotpluggable buses, where child devices could indeed disappear on resume, but as long as they don't, everything stays the same. It's really surprising for something that's soldered onto the board like ME. Aside: We'll probably need a device_link to make sure mei_hdcp is fully resumed before i915 gets resumed, but that's kinda a detail for later on. Tomas, can you pls explain why mei is designed like this? Or is there something else we're missing (I didn't dig through the mei bus in detail at all, so not clear on what exactly is going on there). Also pulling in device model and suspend/resume experts. Thanks, Daniel > > -Ram > > On 12/13/2018 9:31 AM, Ramalingam C wrote: > > Mei hdcp driver is designed as component slave for the I915 component > master. > > v2: Rebased. > v3: > Notifier chain is adopted for cldev state update [Tomas] > v4: > Made static dummy functions as inline in mei_hdcp.h > API for polling client device status > IS_ENABLED used in header, for config status for mei_hdcp. > v5: > Replacing the notifier with component framework. [Daniel] > v6: > Rebased on the I915 comp master redesign. > v7: > mei_hdcp_component_registered is made static [Uma] > Need for global static variable mei_cldev is removed. > > Signed-off-by: Ramalingam C > Reviewed-by: Uma Shankar > --- > drivers/misc/mei/hdcp/mei_hdcp.c | 67 > +--- > 1 file changed, 63 insertions(+), 4 deletions(-) > > diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c > b/drivers/misc/mei/hdcp/mei_hdcp.c > index b22a71e8c5d7..3de1700dcc9f 100644 > --- a/drivers/misc/mei/hdcp/mei_hdcp.c > +++ b/drivers/misc/mei/hdcp/mei_hdcp.c > @@ -23,11 +23,14 @@ > #include > #include > #include > +#include > #include > #include > > #include "mei_hdcp.h" > > +static bool mei_hdcp_component_registered; > + > /** > * mei_initiate_hdcp2_session() - Initiate a Wired HDCP2.2 Tx Session in ME > FW > * @dev: device corresponding to the mei_cl_device > @@ -691,8 +694,7 @@ mei_close_hdcp_session(struct device *dev, struct > hdcp_port_data *data) > return 0; > } > > -static __attribute__((unused)) > -struct i915_hdcp_component_ops mei_hdcp_ops = { > +static struct i915_hdcp_component_ops mei_hdcp_ops = { > .owner = THIS_MODULE, > .initiate_hdcp2_session = mei_initiate_hdcp2_session, > .verify_receiver_cert_prepare_km = mei_verify_receiver_cert_prepare_km, > @@ -707,20 +709,77 @@ struct i915_hdcp_component_ops mei_hdcp_ops = { > .close_hdcp_session = mei_close_hdcp_session, > }; > > +static int mei_hdcp_component_bind(struct device *mei_kdev, > + struct device *i915_kdev, void *data) > +{ > + struct i915_component_master *master_comp = data; > + > + dev_info(mei_kdev, "MEI HDCP comp bind\n"); > + WARN_ON(master_comp->hdcp_ops); > + master_comp->hdcp_ops = &mei_hdcp_ops; > + master_comp->mei_dev = mei_kdev; > + > + return 0; > +} > + > +static void mei_hdcp_component_unbind(struct device *mei_kdev, > + struct device *i915_kdev, void *data) > +{ > + struct i915_component_master *master_comp = data; > + > + dev_info(mei_kdev, "MEI HDCP comp unbind\n"); > + master_comp->hdcp_ops = NULL; > + master_comp->mei_dev = NULL; > +} > + > +static const struct component_ops mei_hdcp_component_
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
> On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam > wrote: > > > > Tomas and Daniel, > > > > We got an issue here. > > > > The relationship that we try to build between I915 and mei_hdcp is as > > follows: > > > > We are using the components to establish the relationship. > > I915 is component master where as mei_hdcp is component. > > I915 adds the component master during the module load. mei_hdcp adds the > component when the driver->probe is called (on device driver binding). > > I915 forces itself such that until mei_hdcp component is added I915_load > wont be complete. > > Similarly on complete system, if mei_hdcp component is removed, > immediately I915 unregister itself and HW will be shutdown. > > > > This is completely fine when the modules are loaded and unloaded. > > > > But during suspend, mei device disappears and mei bus handles it by > unbinding device and driver by calling driver->remove. > > This in-turn removes the component and triggers the master unbind of I915 > where, I915 unregister itself. > > This cause the HW state mismatch during the suspend and resume. > > > > Please check the powerwell mismatch errors at CI report for v9 > > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4005/igt@ > > gem_exec_susp...@basic-s3.html > > > > More over unregistering I915 during the suspend is not expected. So how do > we handle this? > > Bit more context from our irc discussion with Ram: > > I found this very surprising, since I don't know of any other subsystems where > the devices get outright removed when going through a suspend/resume cycle. > The device model was built to handle this stuff > correctly: First clients/devices/interfaces get suspend, then the > parent/bridge/bus. Same dance in reverse when resuming. This even holds for > lots of hotpluggable buses, where child devices could indeed disappear on > resume, but as long as they don't, everything stays the same. It's really > surprising for something that's soldered onto the board like ME. HDCP is an application in the ME it's not ME itself.. On the linux side HDCP2 is a virtual device on mei client virtual bus, the bus is teared down on ME reset, which mostly happen on power transitions. Theoretically, we could keep it up during power transitions, but so fare it was not necessary and second it's not guarantie that the all ME applications will reappear after reset. > > Aside: We'll probably need a device_link to make sure mei_hdcp is fully > resumed before i915 gets resumed, but that's kinda a detail for later on. Frankly I don’t believe there is currently exact abstraction that supports this model, neither components nor device_link . So fare we used class interface for other purposes, it worked well. > > Tomas, can you pls explain why mei is designed like this? Or is there > something > else we're missing (I didn't dig through the mei bus in detail at all, so not > clear > on what exactly is going on there). Above. > > Also pulling in device model and suspend/resume experts. > > Thanks, Daniel > > > > > -Ram > > > > On 12/13/2018 9:31 AM, Ramalingam C wrote: > > > > Mei hdcp driver is designed as component slave for the I915 component > > master. > > > > v2: Rebased. > > v3: > > Notifier chain is adopted for cldev state update [Tomas] > > v4: > > Made static dummy functions as inline in mei_hdcp.h > > API for polling client device status > > IS_ENABLED used in header, for config status for mei_hdcp. > > v5: > > Replacing the notifier with component framework. [Daniel] > > v6: > > Rebased on the I915 comp master redesign. > > v7: > > mei_hdcp_component_registered is made static [Uma] > > Need for global static variable mei_cldev is removed. > > > > Signed-off-by: Ramalingam C > > Reviewed-by: Uma Shankar > > --- > > drivers/misc/mei/hdcp/mei_hdcp.c | 67 > > +--- > > 1 file changed, 63 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c > > b/drivers/misc/mei/hdcp/mei_hdcp.c > > index b22a71e8c5d7..3de1700dcc9f 100644 > > --- a/drivers/misc/mei/hdcp/mei_hdcp.c > > +++ b/drivers/misc/mei/hdcp/mei_hdcp.c > > @@ -23,11 +23,14 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > > > #include "mei_hdcp.h" > > > > +static bool mei_hdcp_component_registered; > > + > > /** > > * mei_initiate_hdcp2_session() - Initiate a Wired HDCP2.2 Tx Session in ME > FW > > * @dev: device corresponding to the mei_cl_device @@ -691,8 +694,7 > > @@ mei_close_hdcp_session(struct device *dev, struct hdcp_port_data > *data) > > return 0; > > } > > > > -static __attribute__((unused)) > > -struct i915_hdcp_component_ops mei_hdcp_ops = { > > +static struct i915_hdcp_component_ops mei_hdcp_ops = { > > .owner = THIS_MODULE, > > .initiate_hdcp2_session = mei_initiate_hdcp2_session, > > .verify_receiver_cert_prepare_km = > > mei_verify_receiver_cert_prepare_km, > > @@ -707,20 +709,77 @@
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
On Thu, Dec 13, 2018 at 5:27 PM Winkler, Tomas wrote: > > > On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam > > wrote: > > > > > > Tomas and Daniel, > > > > > > We got an issue here. > > > > > > The relationship that we try to build between I915 and mei_hdcp is as > > > follows: > > > > > > We are using the components to establish the relationship. > > > I915 is component master where as mei_hdcp is component. > > > I915 adds the component master during the module load. mei_hdcp adds the > > component when the driver->probe is called (on device driver binding). > > > I915 forces itself such that until mei_hdcp component is added I915_load > > wont be complete. > > > Similarly on complete system, if mei_hdcp component is removed, > > immediately I915 unregister itself and HW will be shutdown. > > > > > > This is completely fine when the modules are loaded and unloaded. > > > > > > But during suspend, mei device disappears and mei bus handles it by > > unbinding device and driver by calling driver->remove. > > > This in-turn removes the component and triggers the master unbind of I915 > > where, I915 unregister itself. > > > This cause the HW state mismatch during the suspend and resume. > > > > > > Please check the powerwell mismatch errors at CI report for v9 > > > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4005/igt@ > > > gem_exec_susp...@basic-s3.html > > > > > > More over unregistering I915 during the suspend is not expected. So how do > > we handle this? > > > > Bit more context from our irc discussion with Ram: > > > > I found this very surprising, since I don't know of any other subsystems > > where > > the devices get outright removed when going through a suspend/resume cycle. > > The device model was built to handle this stuff > > correctly: First clients/devices/interfaces get suspend, then the > > parent/bridge/bus. Same dance in reverse when resuming. This even holds for > > lots of hotpluggable buses, where child devices could indeed disappear on > > resume, but as long as they don't, everything stays the same. It's really > > surprising for something that's soldered onto the board like ME. > > HDCP is an application in the ME it's not ME itself.. On the linux side > HDCP2 is a virtual device on mei client virtual bus, > the bus is teared down on ME reset, which mostly happen on power > transitions. > Theoretically, we could keep it up during power transitions, but so fare it > was not necessary > and second it's not guarantie that the all ME applications will reappear > after reset. When does this happen that an ME application doesn't come back after e.g. suspend/resume? Also, what's all the place where this reset can happen? Just suspend/resume/hibernate and all these, or also at other times? How does userspace deal with the reset over s/r? I'm assuming that at least the device node file will become invalid (or whatever you're using as userspace api), so if userspace is accessing stuff on the me at the same time as we do a suspend/resume, what happens? > > Aside: We'll probably need a device_link to make sure mei_hdcp is fully > > resumed before i915 gets resumed, but that's kinda a detail for later on. > > Frankly I don’t believe there is currently exact abstraction that supports > this model, > neither components nor device_link . > So fare we used class interface for other purposes, it worked well. I'm not clear on what class interface has to do with component or device link. They all solve different problems, at least as far as I understand all this stuff ... -Daniel > > Tomas, can you pls explain why mei is designed like this? Or is there > > something > > else we're missing (I didn't dig through the mei bus in detail at all, so > > not clear > > on what exactly is going on there). > Above. > > > > Also pulling in device model and suspend/resume experts. > > > > Thanks, Daniel > > > > > > > > -Ram > > > > > > On 12/13/2018 9:31 AM, Ramalingam C wrote: > > > > > > Mei hdcp driver is designed as component slave for the I915 component > > > master. > > > > > > v2: Rebased. > > > v3: > > > Notifier chain is adopted for cldev state update [Tomas] > > > v4: > > > Made static dummy functions as inline in mei_hdcp.h > > > API for polling client device status > > > IS_ENABLED used in header, for config status for mei_hdcp. > > > v5: > > > Replacing the notifier with component framework. [Daniel] > > > v6: > > > Rebased on the I915 comp master redesign. > > > v7: > > > mei_hdcp_component_registered is made static [Uma] > > > Need for global static variable mei_cldev is removed. > > > > > > Signed-off-by: Ramalingam C > > > Reviewed-by: Uma Shankar > > > --- > > > drivers/misc/mei/hdcp/mei_hdcp.c | 67 > > > +--- > > > 1 file changed, 63 insertions(+), 4 deletions(-) > > > > > > diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c > > > b/drivers/misc/mei/hdcp/mei_hdcp.c > > > index b22a71e8c5d7..3de1700dcc9f 1006
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
> > On Thu, Dec 13, 2018 at 5:27 PM Winkler, Tomas > wrote: > > > > > On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam > > > > > > wrote: > > > > > > > > Tomas and Daniel, > > > > > > > > We got an issue here. > > > > > > > > The relationship that we try to build between I915 and mei_hdcp is as > follows: > > > > > > > > We are using the components to establish the relationship. > > > > I915 is component master where as mei_hdcp is component. > > > > I915 adds the component master during the module load. mei_hdcp > > > > adds the > > > component when the driver->probe is called (on device driver binding). > > > > I915 forces itself such that until mei_hdcp component is added > > > > I915_load > > > wont be complete. > > > > Similarly on complete system, if mei_hdcp component is removed, > > > immediately I915 unregister itself and HW will be shutdown. > > > > > > > > This is completely fine when the modules are loaded and unloaded. > > > > > > > > But during suspend, mei device disappears and mei bus handles it > > > > by > > > unbinding device and driver by calling driver->remove. > > > > This in-turn removes the component and triggers the master unbind > > > > of I915 > > > where, I915 unregister itself. > > > > This cause the HW state mismatch during the suspend and resume. > > > > > > > > Please check the powerwell mismatch errors at CI report for v9 > > > > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4005/ > > > > igt@ > > > > gem_exec_susp...@basic-s3.html > > > > > > > > More over unregistering I915 during the suspend is not expected. > > > > So how do > > > we handle this? > > > > > > Bit more context from our irc discussion with Ram: > > > > > > I found this very surprising, since I don't know of any other > > > subsystems where the devices get outright removed when going through a > suspend/resume cycle. > > > The device model was built to handle this stuff > > > correctly: First clients/devices/interfaces get suspend, then the > > > parent/bridge/bus. Same dance in reverse when resuming. This even > > > holds for lots of hotpluggable buses, where child devices could > > > indeed disappear on resume, but as long as they don't, everything > > > stays the same. It's really surprising for something that's soldered onto > > > the > board like ME. > > > > HDCP is an application in the ME it's not ME itself.. On the linux > > side HDCP2 is a virtual device on mei client virtual bus, the bus is > > teared > down on ME reset, which mostly happen on power transitions. > > Theoretically, we could keep it up during power transitions, but so > > fare it was not necessary and second it's not guarantie that the all ME > applications will reappear after reset. > > When does this happen that an ME application doesn't come back after e.g. > suspend/resume? No, this can happen in special flows such as fw updates and error conditions, but is has to be supported as well. > > Also, what's all the place where this reset can happen? Just > suspend/resume/hibernate and all these, or also at other times? Also on errors and fw update, the basic assumption is here that it can happen any time. > How does userspace deal with the reset over s/r? I'm assuming that at least > the > device node file will become invalid (or whatever you're using as userspace > api), so if userspace is accessing stuff on the me at the same time as we do a > suspend/resume, what happens? > > > > Aside: We'll probably need a device_link to make sure mei_hdcp is > > > fully resumed before i915 gets resumed, but that's kinda a detail for > > > later > on. > > > > Frankly I don’t believe there is currently exact abstraction that > > supports this model, neither components nor device_link . > > So fare we used class interface for other purposes, it worked well. > > I'm not clear on what class interface has to do with component or device link. > They all solve different problems, at least as far as I understand all this > stuff ... > -Daniel It comes instead of it, device_link is mostly used for power management and component as we see know is not what we need as HDCP Is a b it volitle. class_interface gives you two handlers: add and remove device, that's all what is needed for the current implementation. > > > > Tomas, can you pls explain why mei is designed like this? Or is > > > there something else we're missing (I didn't dig through the mei bus > > > in detail at all, so not clear on what exactly is going on there). > > Above. > > > > > > Also pulling in device model and suspend/resume experts. > > > > > > Thanks, Daniel > > > > > > > > > > > -Ram > > > > > > > > On 12/13/2018 9:31 AM, Ramalingam C wrote: > > > > > > > > Mei hdcp driver is designed as component slave for the I915 > > > > component master. > > > > > > > > v2: Rebased. > > > > v3: > > > > Notifier chain is adopted for cldev state update [Tomas] > > > > v4: > > > > Made static dummy functions as inline in mei_hdcp.h > > > > API for
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
On Sat, Dec 15, 2018 at 09:20:38PM +, Winkler, Tomas wrote: > > > > On Thu, Dec 13, 2018 at 5:27 PM Winkler, Tomas > > wrote: > > > > > > > On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam > > > > > > > > wrote: > > > > > > > > > > Tomas and Daniel, > > > > > > > > > > We got an issue here. > > > > > > > > > > The relationship that we try to build between I915 and mei_hdcp is as > > follows: > > > > > > > > > > We are using the components to establish the relationship. > > > > > I915 is component master where as mei_hdcp is component. > > > > > I915 adds the component master during the module load. mei_hdcp > > > > > adds the > > > > component when the driver->probe is called (on device driver binding). > > > > > I915 forces itself such that until mei_hdcp component is added > > > > > I915_load > > > > wont be complete. > > > > > Similarly on complete system, if mei_hdcp component is removed, > > > > immediately I915 unregister itself and HW will be shutdown. > > > > > > > > > > This is completely fine when the modules are loaded and unloaded. > > > > > > > > > > But during suspend, mei device disappears and mei bus handles it > > > > > by > > > > unbinding device and driver by calling driver->remove. > > > > > This in-turn removes the component and triggers the master unbind > > > > > of I915 > > > > where, I915 unregister itself. > > > > > This cause the HW state mismatch during the suspend and resume. > > > > > > > > > > Please check the powerwell mismatch errors at CI report for v9 > > > > > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4005/ > > > > > igt@ > > > > > gem_exec_susp...@basic-s3.html > > > > > > > > > > More over unregistering I915 during the suspend is not expected. > > > > > So how do > > > > we handle this? > > > > > > > > Bit more context from our irc discussion with Ram: > > > > > > > > I found this very surprising, since I don't know of any other > > > > subsystems where the devices get outright removed when going through a > > suspend/resume cycle. > > > > The device model was built to handle this stuff > > > > correctly: First clients/devices/interfaces get suspend, then the > > > > parent/bridge/bus. Same dance in reverse when resuming. This even > > > > holds for lots of hotpluggable buses, where child devices could > > > > indeed disappear on resume, but as long as they don't, everything > > > > stays the same. It's really surprising for something that's soldered > > > > onto the > > board like ME. > > > > > > HDCP is an application in the ME it's not ME itself.. On the linux > > > side HDCP2 is a virtual device on mei client virtual bus, the bus is > > > teared > > down on ME reset, which mostly happen on power transitions. > > > Theoretically, we could keep it up during power transitions, but so > > > fare it was not necessary and second it's not guarantie that the all ME > > applications will reappear after reset. > > > > When does this happen that an ME application doesn't come back after e.g. > > suspend/resume? > No, this can happen in special flows such as fw updates and error > conditions, but is has to be supported as well. > > > > > Also, what's all the place where this reset can happen? Just > > suspend/resume/hibernate and all these, or also at other times? > > Also on errors and fw update, the basic assumption is here that it can > happen any time. If this can happen any time, what are we supposed to do if this happens while we're doing something with the hdcp mei? If this is such a common occurence I guess we need to somehow wait until everyting is rebound and working again. I think ideally mei core would handle that for us, but I guess if this just randomly happens then we need to redo all the transactions. So does need some involvement of the higher levels. Also, how likely is it that the hdcp mei will outright disappear and not come back after a reset? > > How does userspace deal with the reset over s/r? I'm assuming that at least > > the > > device node file will become invalid (or whatever you're using as userspace > > api), so if userspace is accessing stuff on the me at the same time as we > > do a > > suspend/resume, what happens? Also, answer to how other users handle this would be enlighting. > > > > Aside: We'll probably need a device_link to make sure mei_hdcp is > > > > fully resumed before i915 gets resumed, but that's kinda a detail for > > > > later > > on. > > > > > > Frankly I don’t believe there is currently exact abstraction that > > > supports this model, neither components nor device_link . > > > So fare we used class interface for other purposes, it worked well. > > > > I'm not clear on what class interface has to do with component or device > > link. > > They all solve different problems, at least as far as I understand all this > > stuff ... > > -Daniel > > It comes instead of it, device_link is mostly used for power management and > component as we see know is not what we need as HDCP > I
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
On Mon, Dec 17, 2018 at 10:39:07AM +0100, Daniel Vetter wrote: > On Sat, Dec 15, 2018 at 09:20:38PM +, Winkler, Tomas wrote: > > > > > > On Thu, Dec 13, 2018 at 5:27 PM Winkler, Tomas > > > wrote: > > > > > > > > > On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam > > > > > > > > > > wrote: > > > > > > > > > > > > Tomas and Daniel, > > > > > > > > > > > > We got an issue here. > > > > > > > > > > > > The relationship that we try to build between I915 and mei_hdcp is > > > > > > as > > > follows: > > > > > > > > > > > > We are using the components to establish the relationship. > > > > > > I915 is component master where as mei_hdcp is component. > > > > > > I915 adds the component master during the module load. mei_hdcp > > > > > > adds the > > > > > component when the driver->probe is called (on device driver binding). > > > > > > I915 forces itself such that until mei_hdcp component is added > > > > > > I915_load > > > > > wont be complete. > > > > > > Similarly on complete system, if mei_hdcp component is removed, > > > > > immediately I915 unregister itself and HW will be shutdown. > > > > > > > > > > > > This is completely fine when the modules are loaded and unloaded. > > > > > > > > > > > > But during suspend, mei device disappears and mei bus handles it > > > > > > by > > > > > unbinding device and driver by calling driver->remove. > > > > > > This in-turn removes the component and triggers the master unbind > > > > > > of I915 > > > > > where, I915 unregister itself. > > > > > > This cause the HW state mismatch during the suspend and resume. > > > > > > > > > > > > Please check the powerwell mismatch errors at CI report for v9 > > > > > > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4005/ > > > > > > igt@ > > > > > > gem_exec_susp...@basic-s3.html > > > > > > > > > > > > More over unregistering I915 during the suspend is not expected. > > > > > > So how do > > > > > we handle this? > > > > > > > > > > Bit more context from our irc discussion with Ram: > > > > > > > > > > I found this very surprising, since I don't know of any other > > > > > subsystems where the devices get outright removed when going through a > > > suspend/resume cycle. > > > > > The device model was built to handle this stuff > > > > > correctly: First clients/devices/interfaces get suspend, then the > > > > > parent/bridge/bus. Same dance in reverse when resuming. This even > > > > > holds for lots of hotpluggable buses, where child devices could > > > > > indeed disappear on resume, but as long as they don't, everything > > > > > stays the same. It's really surprising for something that's soldered > > > > > onto the > > > board like ME. > > > > > > > > HDCP is an application in the ME it's not ME itself.. On the linux > > > > side HDCP2 is a virtual device on mei client virtual bus, the bus is > > > > teared > > > down on ME reset, which mostly happen on power transitions. > > > > Theoretically, we could keep it up during power transitions, but so > > > > fare it was not necessary and second it's not guarantie that the all ME > > > applications will reappear after reset. > > > > > > When does this happen that an ME application doesn't come back after e.g. > > > suspend/resume? > > No, this can happen in special flows such as fw updates and error > > conditions, but is has to be supported as well. > > > > > > > > Also, what's all the place where this reset can happen? Just > > > suspend/resume/hibernate and all these, or also at other times? > > > > Also on errors and fw update, the basic assumption is here that it can > > happen any time. > > If this can happen any time, what are we supposed to do if this happens > while we're doing something with the hdcp mei? If this is such a common > occurence I guess we need to somehow wait until everyting is rebound and > working again. I think ideally mei core would handle that for us, but I > guess if this just randomly happens then we need to redo all the > transactions. So does need some involvement of the higher levels. Few more questions on this, beyond the ones in the previous mail. So generally drivers don't support upgrading the fw at runtime, but only look once for upgraded fw on driver load (before anyone is using is). What's the use-case that requires this. I'm also rather worried about "this can happen any time". Is ME fw so unstable it just randomly crashes for no good reason at all, taking our hdcp session with it? Or is this more like "cosmic rays can happen" kind of problem (which we don't care about)? > > Also, how likely is it that the hdcp mei will outright disappear and not > come back after a reset? > > > > How does userspace deal with the reset over s/r? I'm assuming that at > > > least the > > > device node file will become invalid (or whatever you're using as > > > userspace > > > api), so if userspace is accessing stuff on the me at the same time as we > > > do a > > > suspend/resume, what happens? > > Also, answe
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
> On Sat, Dec 15, 2018 at 09:20:38PM +, Winkler, Tomas wrote: > > > > > > On Thu, Dec 13, 2018 at 5:27 PM Winkler, Tomas > > > > > > wrote: > > > > > > > > > On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam > > > > > > > > > > wrote: > > > > > > > > > > > > Tomas and Daniel, > > > > > > > > > > > > We got an issue here. > > > > > > > > > > > > The relationship that we try to build between I915 and > > > > > > mei_hdcp is as > > > follows: > > > > > > > > > > > > We are using the components to establish the relationship. > > > > > > I915 is component master where as mei_hdcp is component. > > > > > > I915 adds the component master during the module load. > > > > > > mei_hdcp adds the > > > > > component when the driver->probe is called (on device driver binding). > > > > > > I915 forces itself such that until mei_hdcp component is added > > > > > > I915_load > > > > > wont be complete. > > > > > > Similarly on complete system, if mei_hdcp component is > > > > > > removed, > > > > > immediately I915 unregister itself and HW will be shutdown. > > > > > > > > > > > > This is completely fine when the modules are loaded and unloaded. > > > > > > > > > > > > But during suspend, mei device disappears and mei bus handles > > > > > > it by > > > > > unbinding device and driver by calling driver->remove. > > > > > > This in-turn removes the component and triggers the master > > > > > > unbind of I915 > > > > > where, I915 unregister itself. > > > > > > This cause the HW state mismatch during the suspend and resume. > > > > > > > > > > > > Please check the powerwell mismatch errors at CI report for v9 > > > > > > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4 > > > > > > 005/ > > > > > > igt@ > > > > > > gem_exec_susp...@basic-s3.html > > > > > > > > > > > > More over unregistering I915 during the suspend is not expected. > > > > > > So how do > > > > > we handle this? > > > > > > > > > > Bit more context from our irc discussion with Ram: > > > > > > > > > > I found this very surprising, since I don't know of any other > > > > > subsystems where the devices get outright removed when going > > > > > through a > > > suspend/resume cycle. > > > > > The device model was built to handle this stuff > > > > > correctly: First clients/devices/interfaces get suspend, then > > > > > the parent/bridge/bus. Same dance in reverse when resuming. This > > > > > even holds for lots of hotpluggable buses, where child devices > > > > > could indeed disappear on resume, but as long as they don't, > > > > > everything stays the same. It's really surprising for something > > > > > that's soldered onto the > > > board like ME. > > > > > > > > HDCP is an application in the ME it's not ME itself.. On the > > > > linux side HDCP2 is a virtual device on mei client virtual bus, > > > > the bus is teared > > > down on ME reset, which mostly happen on power transitions. > > > > Theoretically, we could keep it up during power transitions, but > > > > so fare it was not necessary and second it's not guarantie that > > > > the all ME > > > applications will reappear after reset. > > > > > > When does this happen that an ME application doesn't come back after e.g. > > > suspend/resume? > > No, this can happen in special flows such as fw updates and error > > conditions, > but is has to be supported as well. > > > > > > > > Also, what's all the place where this reset can happen? Just > > > suspend/resume/hibernate and all these, or also at other times? > > > > Also on errors and fw update, the basic assumption is here that it can > > happen > any time. > > If this can happen any time, what are we supposed to do if this happens while > we're doing something with the hdcp mei? If this is such a common occurence I > guess we need to somehow wait until everyting is rebound and working again. I > think ideally mei core would handle that for us, but I guess if this just > randomly > happens then we need to redo all the transactions. So does need some > involvement of the higher levels. It's not common occurrence, but the assumption must be it can happen any time, In that case everything has to restarted as there is no state preserved in the ME FW. Right MEI core cannot do it for you, it is just a channel, the logic and state of the connection is in the mei_hdcp or gfx. Note that HDCP is not the only App over MEI. > > Also, how likely is it that the hdcp mei will outright disappear and not come > back after a reset? > > > > How does userspace deal with the reset over s/r? I'm assuming that > > > at least the device node file will become invalid (or whatever > > > you're using as userspace api), so if userspace is accessing stuff > > > on the me at the same time as we do a suspend/resume, what happens? > > Also, answer to how other users handle this would be enlighting. > > > > > > Aside: We'll probably need a device_link to make sure mei_hdcp > > > > > is fully resumed before i915 gets resumed, but that's kinda a > >
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
On Mon, Dec 17, 2018 at 11:57 AM Winkler, Tomas wrote: > > > > On Sat, Dec 15, 2018 at 09:20:38PM +, Winkler, Tomas wrote: > > > > > > > > On Thu, Dec 13, 2018 at 5:27 PM Winkler, Tomas > > > > > > > > wrote: > > > > > > > > > > > On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > Tomas and Daniel, > > > > > > > > > > > > > > We got an issue here. > > > > > > > > > > > > > > The relationship that we try to build between I915 and > > > > > > > mei_hdcp is as > > > > follows: > > > > > > > > > > > > > > We are using the components to establish the relationship. > > > > > > > I915 is component master where as mei_hdcp is component. > > > > > > > I915 adds the component master during the module load. > > > > > > > mei_hdcp adds the > > > > > > component when the driver->probe is called (on device driver > > > > > > binding). > > > > > > > I915 forces itself such that until mei_hdcp component is added > > > > > > > I915_load > > > > > > wont be complete. > > > > > > > Similarly on complete system, if mei_hdcp component is > > > > > > > removed, > > > > > > immediately I915 unregister itself and HW will be shutdown. > > > > > > > > > > > > > > This is completely fine when the modules are loaded and unloaded. > > > > > > > > > > > > > > But during suspend, mei device disappears and mei bus handles > > > > > > > it by > > > > > > unbinding device and driver by calling driver->remove. > > > > > > > This in-turn removes the component and triggers the master > > > > > > > unbind of I915 > > > > > > where, I915 unregister itself. > > > > > > > This cause the HW state mismatch during the suspend and resume. > > > > > > > > > > > > > > Please check the powerwell mismatch errors at CI report for v9 > > > > > > > https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4 > > > > > > > 005/ > > > > > > > igt@ > > > > > > > gem_exec_susp...@basic-s3.html > > > > > > > > > > > > > > More over unregistering I915 during the suspend is not expected. > > > > > > > So how do > > > > > > we handle this? > > > > > > > > > > > > Bit more context from our irc discussion with Ram: > > > > > > > > > > > > I found this very surprising, since I don't know of any other > > > > > > subsystems where the devices get outright removed when going > > > > > > through a > > > > suspend/resume cycle. > > > > > > The device model was built to handle this stuff > > > > > > correctly: First clients/devices/interfaces get suspend, then > > > > > > the parent/bridge/bus. Same dance in reverse when resuming. This > > > > > > even holds for lots of hotpluggable buses, where child devices > > > > > > could indeed disappear on resume, but as long as they don't, > > > > > > everything stays the same. It's really surprising for something > > > > > > that's soldered onto the > > > > board like ME. > > > > > > > > > > HDCP is an application in the ME it's not ME itself.. On the > > > > > linux side HDCP2 is a virtual device on mei client virtual bus, > > > > > the bus is teared > > > > down on ME reset, which mostly happen on power transitions. > > > > > Theoretically, we could keep it up during power transitions, but > > > > > so fare it was not necessary and second it's not guarantie that > > > > > the all ME > > > > applications will reappear after reset. > > > > > > > > When does this happen that an ME application doesn't come back after > > > > e.g. > > > > suspend/resume? > > > No, this can happen in special flows such as fw updates and error > > > conditions, > > but is has to be supported as well. > > > > > > > > > > > Also, what's all the place where this reset can happen? Just > > > > suspend/resume/hibernate and all these, or also at other times? > > > > > > Also on errors and fw update, the basic assumption is here that it can > > > happen > > any time. > > > > If this can happen any time, what are we supposed to do if this happens > > while > > we're doing something with the hdcp mei? If this is such a common occurence > > I > > guess we need to somehow wait until everyting is rebound and working again. > > I > > think ideally mei core would handle that for us, but I guess if this just > > randomly > > happens then we need to redo all the transactions. So does need some > > involvement of the higher levels. > > It's not common occurrence, but the assumption must be it can happen any time, > In that case everything has to restarted as there is no state preserved in > the ME FW. > Right MEI core cannot do it for you, it is just a channel, the logic and > state of the connection > is in the mei_hdcp or gfx. Note that HDCP is not the only App over MEI. Yes, each mei interface would need to provide suspend/resume functions, or something like that. Or at least a reset function. > > Also, how likely is it that the hdcp mei will outright disappear and not > > come > > back after a reset? > > > > > > How does userspace deal with the reset over s/r? I'm assuming that > >
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
Tomas and Daniel, From the discussion on this thread, I infer following understanding: * At present(v9) I915 wants to be hard binded to mei_hdcp device-driver binding status through components o This means I915 driver load will get complete only when the mei_hdcp's device and driver are bound. o if mei_hdcp device reset I915 will unregister itself from userspace, and wait for the mei_hdcp device-deriver rebinding. + Could be due to FW error or any unexpected failures those are rare occurances. o when mei_hdcp module is removed i915 will unregister itself. o Becasue of this, Ideally I915 dont expect the device reset from mei for suspend and resume. * At present Mei bus is designed as below: o Device will disappear on FW failures, FW upgrade, suspend of the system etc. o And when the errors are handled or on system resume mei device will reappear, hence binding with corresponding driver. * Mei doesn't plan to avoid the device reset(disappearance and reappearance) for suspend and resume in near future. Based on above understanding, I propose the below approach. Please correct or approve it. * At present(v9) component_add from mei_hdcp indicates the mei_hdcp's device-driver binded state. * Instead lets use component to indicate the mei_hdcp's module availability, o by adding the component at module_init and removing it from module_exit. * This way I915 will not be impacted due to the mei device reset at suspend. * In such scenario I915 will have no idea about the device-driver bind status of mei_hdcp. o So incase of device is not available, mei_hdcp is responsible to prune such calls with -EIO error. * This approach avoid any future impact to I915, incase mei intended to support suspend and resume. I am aware this is not the ideal solution we want. But I feel this is the best at present we could do for this I915-mei interface. Best regards, Ram On 12/17/2018 7:16 PM, Daniel Vetter wrote: On Mon, Dec 17, 2018 at 11:57 AM Winkler, Tomas wrote: On Sat, Dec 15, 2018 at 09:20:38PM +, Winkler, Tomas wrote: On Thu, Dec 13, 2018 at 5:27 PM Winkler, Tomas wrote: On Thu, Dec 13, 2018 at 1:36 PM C, Ramalingam wrote: Tomas and Daniel, We got an issue here. The relationship that we try to build between I915 and mei_hdcp is as follows: We are using the components to establish the relationship. I915 is component master where as mei_hdcp is component. I915 adds the component master during the module load. mei_hdcp adds the component when the driver->probe is called (on device driver binding). I915 forces itself such that until mei_hdcp component is added I915_load wont be complete. Similarly on complete system, if mei_hdcp component is removed, immediately I915 unregister itself and HW will be shutdown. This is completely fine when the modules are loaded and unloaded. But during suspend, mei device disappears and mei bus handles it by unbinding device and driver by calling driver->remove. This in-turn removes the component and triggers the master unbind of I915 where, I915 unregister itself. This cause the HW state mismatch during the suspend and resume. Please check the powerwell mismatch errors at CI report for v9 https://intel-gfx-ci.01.org/tree/drm-tip/Trybot_3412/fi-glk-j4 005/ igt@ gem_exec_susp...@basic-s3.html More over unregistering I915 during the suspend is not expected. So how do we handle this? Bit more context from our irc discussion with Ram: I found this very surprising, since I don't know of any other subsystems where the devices get outright removed when going through a suspend/resume cycle. The device model was built to handle this stuff correctly: First clients/devices/interfaces get suspend, then the parent/bridge/bus. Same dance in reverse when resuming. This even holds for lots of hotpluggable buses, where child devices could indeed disappear on resume, but as long as they don't, everything stays the same. It's really surprising for something that's soldered onto the board like ME. HDCP is an application in the ME it's not ME itself.. On the linux side HDCP2 is a virtual device on mei client virtual bus, the bus is teared down on ME reset, which mostly happen on power transitions. Theoretically, we could keep it up during power transitions, but so fare it was not necessary and second it's not guarantie that the all ME applications will reappear after reset. When does this happen that an ME application doesn't come back after e.g. suspend/resume? No, this can happen in special flows such as fw updates and error conditions, but is has to be supported as well. Also, what's all the place where this reset can happen? Just suspend/resume/hibernate and all these, or also at other times? Also on errors and fw update, the basic assumption is here that it can happen any time. If this can happen any time, what are
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
On 12/19/2018 12:15 PM, C, Ramalingam wrote: Tomas and Daniel, From the discussion on this thread, I infer following understanding: * At present(v9) I915 wants to be hard binded to mei_hdcp device-driver binding status through components o This means I915 driver load will get complete only when the mei_hdcp's device and driver are bound. o if mei_hdcp device reset I915 will unregister itself from userspace, and wait for the mei_hdcp device-deriver rebinding. + Could be due to FW error or any unexpected failures those are rare occurances. o when mei_hdcp module is removed i915 will unregister itself. o Becasue of this, Ideally I915 dont expect the device reset from mei for suspend and resume. * At present Mei bus is designed as below: o Device will disappear on FW failures, FW upgrade, suspend of the system etc. o And when the errors are handled or on system resume mei device will reappear, hence binding with corresponding driver. * Mei doesn't plan to avoid the device reset(disappearance and reappearance) for suspend and resume in near future. Based on above understanding, I propose the below approach. Please correct or approve it. * At present(v9) component_add from mei_hdcp indicates the mei_hdcp's device-driver binded state. * Instead lets use component to indicate the mei_hdcp's module availability, o by adding the component at module_init and removing it from module_exit. * This way I915 will not be impacted due to the mei device reset at suspend. * In such scenario I915 will have no idea about the device-driver bind status of mei_hdcp. o So incase of device is not available, mei_hdcp is responsible to prune such calls with -EIO error. * This approach avoid any future impact to I915, incase mei intended to support suspend and resume. I am aware this is not the ideal solution we want. But I feel this is the best at present we could do for this I915-mei interface. Best regards, Ram something like (un compiled code) diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c index b22a71e8c5d7..b5b57a883e3b 100644 --- a/drivers/misc/mei/hdcp/mei_hdcp.c +++ b/drivers/misc/mei/hdcp/mei_hdcp.c @@ -23,11 +23,15 @@ #include #include #include +#include #include #include #include "mei_hdcp.h" +struct i915_component_master *i915_master_comp; +static bool mei_hdcp_component_registered; + /** * mei_initiate_hdcp2_session() - Initiate a Wired HDCP2.2 Tx Session in ME FW * @dev: device corresponding to the mei_cl_device @@ -691,8 +695,7 @@ mei_close_hdcp_session(struct device *dev, struct hdcp_port_data *data) return 0; } -static __attribute__((unused)) -struct i915_hdcp_component_ops mei_hdcp_ops = { +static struct i915_hdcp_component_ops mei_hdcp_ops = { .owner = THIS_MODULE, .initiate_hdcp2_session = mei_initiate_hdcp2_session, .verify_receiver_cert_prepare_km = mei_verify_receiver_cert_prepare_km, @@ -707,20 +710,84 @@ struct i915_hdcp_component_ops mei_hdcp_ops = { .close_hdcp_session = mei_close_hdcp_session, }; +static int mei_hdcp_component_bind(struct device *mei_kdev, + struct device *i915_kdev, void *data) +{ + struct i915_component_master *master_comp = data; + + dev_info(mei_kdev, "MEI HDCP comp bind\n"); + WARN_ON(master_comp->hdcp_ops); + master_comp->hdcp_ops = &mei_hdcp_ops; + master_comp->mei_dev = mei_kdev; + + i915_master_comp = master_comp; + + return 0; +} + +static void mei_hdcp_component_unbind(struct device *mei_kdev, + struct device *i915_kdev, void *data) +{ + struct i915_component_master *master_comp = data; + + dev_info(mei_kdev, "MEI HDCP comp unbind\n"); + master_comp->hdcp_ops = NULL; + master_comp->mei_dev = NULL; + i915_master_comp = NULL; +} + +static const struct component_ops mei_hdcp_component_bind_ops = { + .bind = mei_hdcp_component_bind, + .unbind = mei_hdcp_component_unbind, +}; + +static void mei_hdcp_component_init(struct device *dev) +{ + int ret; + + if (mei_hdcp_component_registered && i915_master_comp) { + i915_master_comp->mei_dev = dev; + return; + } + + dev_info(dev, "MEI HDCP comp init\n"); + ret = component_add(dev, &mei_hdcp_component_bind_ops); + if (ret < 0) { + dev_err(dev, "Failed to add MEI HDCP comp (%d)\n", ret); + return; + } + + mei_hdcp_component_registered = true; +} + +static void mei_hdcp_component_cleanup(struct device *dev) +{ + if (!mei_hdcp_component_registered) + return; + + dev_info(dev, "MEI HDCP comp cleanup\n"); + component_del(dev, &mei_hdcp_component_bind_ops); + mei_hdcp_component_re
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
From: C, Ramalingam Sent: Thursday, December 20, 2018 18:00 To: Daniel Vetter ; Winkler, Tomas Cc: Greg KH ; Rafael J. Wysocki ; intel-gfx ; dri-devel ; Sean Paul ; Shankar, Uma ; Syrjala, Ville ; Chris Wilson Subject: Re: [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface On 12/19/2018 12:15 PM, C, Ramalingam wrote: Tomas and Daniel, From the discussion on this thread, I infer following understanding: * At present(v9) I915 wants to be hard binded to mei_hdcp device-driver binding status through components * This means I915 driver load will get complete only when the mei_hdcp's device and driver are bound. * if mei_hdcp device reset I915 will unregister itself from userspace, and wait for the mei_hdcp device-deriver rebinding. * Could be due to FW error or any unexpected failures those are rare occurances. * when mei_hdcp module is removed i915 will unregister itself. * Becasue of this, Ideally I915 dont expect the device reset from mei for suspend and resume. * At present Mei bus is designed as below: * Device will disappear on FW failures, FW upgrade, suspend of the system etc. * And when the errors are handled or on system resume mei device will reappear, hence binding with corresponding driver. * Mei doesn't plan to avoid the device reset(disappearance and reappearance) for suspend and resume in near future. Based on above understanding, I propose the below approach. Please correct or approve it. * At present(v9) component_add from mei_hdcp indicates the mei_hdcp's device-driver binded state. * Instead lets use component to indicate the mei_hdcp's module availability, * by adding the component at module_init and removing it from module_exit. * This way I915 will not be impacted due to the mei device reset at suspend. * In such scenario I915 will have no idea about the device-driver bind status of mei_hdcp. * So incase of device is not available, mei_hdcp is responsible to prune such calls with -EIO error. * This approach avoid any future impact to I915, incase mei intended to support suspend and resume. I am aware this is not the ideal solution we want. But I feel this is the best at present we could do for this I915-mei interface. Best regards, Ram something like (un compiled code) diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c index b22a71e8c5d7..b5b57a883e3b 100644 --- a/drivers/misc/mei/hdcp/mei_hdcp.c +++ b/drivers/misc/mei/hdcp/mei_hdcp.c @@ -23,11 +23,15 @@ #include #include #include +#include #include #include #include "mei_hdcp.h" +struct i915_component_master *i915_master_comp; +static bool mei_hdcp_component_registered; + /** * mei_initiate_hdcp2_session() - Initiate a Wired HDCP2.2 Tx Session in ME FW * @dev: device corresponding to the mei_cl_device @@ -691,8 +695,7 @@ mei_close_hdcp_session(struct device *dev, struct hdcp_port_data *data) return 0; } -static __attribute__((unused)) -struct i915_hdcp_component_ops mei_hdcp_ops = { +static struct i915_hdcp_component_ops mei_hdcp_ops = { .owner = THIS_MODULE, .initiate_hdcp2_session = mei_initiate_hdcp2_session, .verify_receiver_cert_prepare_km = mei_verify_receiver_cert_prepare_km, @@ -707,20 +710,84 @@ struct i915_hdcp_component_ops mei_hdcp_ops = { .close_hdcp_session = mei_close_hdcp_session, }; +static int mei_hdcp_component_bind(struct device *mei_kdev, + struct device *i915_kdev, void *data) +{ + struct i915_component_master *master_comp = data; + + dev_info(mei_kdev, "MEI HDCP comp bind\n"); + WARN_ON(master_comp->hdcp_ops); + master_comp->hdcp_ops = &mei_hdcp_ops; + master_comp->mei_dev = mei_kdev; + + i915_master_comp = master_comp; + + return 0; +} + +static void mei_hdcp_component_unbind(struct device *mei_kdev, + struct device *i915_kdev, void *data) +{ + struct i915_component_master *master_comp = data; + + dev_info(mei_kdev, "MEI HDCP comp unbind\n"); + master_comp->hdcp_ops = NULL; + master_comp->mei_dev = NULL; + i915_master_comp = NULL; +} + +static const struct component_ops mei_hdcp_component_bind_ops = { + .bind = mei_hdcp_component_bind, + .unbind = mei_hdcp_component_unbind, +}; + +static void mei_hdcp_component_init(struct device *dev) +{ + int ret; + + if (mei_hdcp_component_registered && i915_master_comp) { + i915_master_comp->mei_dev = dev; + return; + } + + dev_info(dev, "MEI HDCP comp init\n"); + ret = component_add(dev, &mei_hdcp_component_bind_ops); + if (ret < 0) { + dev_err(dev, "Failed to add MEI HDCP comp (%d)\n", ret); + retu
Re: [Intel-gfx] [PATCH v9 35/39] misc/mei/hdcp: Component framework for I915 Interface
On 12/20/2018 9:36 PM, Winkler, Tomas wrote: +static void __exit mei_hdcp_exit(void) +{ + mei_hdcp_component_cleanup(&cldev->dev); Don’t think you can do that, no guarantees this will be valid pointer As we discussed offline, we have the below line at cleanup. So valid pointer is made sure. I will protect init and cleanup with mutex too. +static void mei_hdcp_component_cleanup(struct device *dev) +{ + if (!mei_hdcp_component_registered) + return; -Ram + mei_cldev_driver_unregister(mei_hdcp_driver); +} + +module_init(mei_hdcp_init); +module_exit(mei_hdcp_exit); ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx