diff mbox series

[v1] misc: fastrpc: Move fastrpc driver to misc/fastrpc/

Message ID 20240612064731.25651-1-quic_ekangupt@quicinc.com
State New
Headers show
Series [v1] misc: fastrpc: Move fastrpc driver to misc/fastrpc/ | expand

Commit Message

Ekansh Gupta June 12, 2024, 6:47 a.m. UTC
Move fastrpc.c from misc/ to misc/fastrpc/. New C files are planned
to be added for PD notifications and other missing features. Adding
and maintaining new files from within fastrpc directory would be easy.

Example of feature that is being planned to be introduced in a new C
file:
https://lore.kernel.org/all/20240606165939.12950-6-quic_ekangupt@quicinc.com/

Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
---
 MAINTAINERS                          |  2 +-
 drivers/misc/Kconfig                 | 13 +------------
 drivers/misc/Makefile                |  2 +-
 drivers/misc/fastrpc/Kconfig         | 16 ++++++++++++++++
 drivers/misc/fastrpc/Makefile        |  2 ++
 drivers/misc/{ => fastrpc}/fastrpc.c |  0
 6 files changed, 21 insertions(+), 14 deletions(-)
 create mode 100644 drivers/misc/fastrpc/Kconfig
 create mode 100644 drivers/misc/fastrpc/Makefile
 rename drivers/misc/{ => fastrpc}/fastrpc.c (100%)

Comments

Dmitry Baryshkov June 12, 2024, 6:28 p.m. UTC | #1
On Wed, Jun 12, 2024 at 12:17:28PM +0530, Ekansh Gupta wrote:
> Move fastrpc.c from misc/ to misc/fastrpc/. New C files are planned
> to be added for PD notifications and other missing features. Adding
> and maintaining new files from within fastrpc directory would be easy.
> 
> Example of feature that is being planned to be introduced in a new C
> file:
> https://lore.kernel.org/all/20240606165939.12950-6-quic_ekangupt@quicinc.com/
> 
> Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
> ---
>  MAINTAINERS                          |  2 +-
>  drivers/misc/Kconfig                 | 13 +------------
>  drivers/misc/Makefile                |  2 +-
>  drivers/misc/fastrpc/Kconfig         | 16 ++++++++++++++++
>  drivers/misc/fastrpc/Makefile        |  2 ++
>  drivers/misc/{ => fastrpc}/fastrpc.c |  0
>  6 files changed, 21 insertions(+), 14 deletions(-)
>  create mode 100644 drivers/misc/fastrpc/Kconfig
>  create mode 100644 drivers/misc/fastrpc/Makefile
>  rename drivers/misc/{ => fastrpc}/fastrpc.c (100%)

Please consider whether it makes sense to move to drivers/accel instead
(and possibly writing a better Kconfig entry, specifying that the driver
is to be used to offload execution to the DSP).

> diff --git a/MAINTAINERS b/MAINTAINERS
> index d6c90161c7bf..e9c79e9063f8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -18501,7 +18501,7 @@ M:	Amol Maheshwari <amahesh@qti.qualcomm.com>
>  L:	linux-arm-msm@vger.kernel.org
>  S:	Maintained
>  F:	Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml
> -F:	drivers/misc/fastrpc.c
> +F:	drivers/misc/fastrpc/
>  F:	include/uapi/misc/fastrpc.h
>  
>  QUALCOMM HEXAGON ARCHITECTURE
> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> index faf983680040..630e8ccd8669 100644
> --- a/drivers/misc/Kconfig
> +++ b/drivers/misc/Kconfig
> @@ -276,18 +276,6 @@ config QCOM_COINCELL
>  	  to maintain PMIC register and RTC state in the absence of
>  	  external power.
>  
> -config QCOM_FASTRPC
> -	tristate "Qualcomm FastRPC"
> -	depends on ARCH_QCOM || COMPILE_TEST
> -	depends on RPMSG
> -	select DMA_SHARED_BUFFER
> -	select QCOM_SCM
> -	help
> -	  Provides a communication mechanism that allows for clients to
> -	  make remote method invocations across processor boundary to
> -	  applications DSP processor. Say M if you want to enable this
> -	  module.
> -
>  config SGI_GRU
>  	tristate "SGI GRU driver"
>  	depends on X86_UV && SMP
> @@ -602,4 +590,5 @@ source "drivers/misc/cardreader/Kconfig"
>  source "drivers/misc/uacce/Kconfig"
>  source "drivers/misc/pvpanic/Kconfig"
>  source "drivers/misc/mchp_pci1xxxx/Kconfig"
> +source "drivers/misc/fastrpc/Kconfig"
>  endmenu
> diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
> index 153a3f4837e8..f83d73844ea5 100644
> --- a/drivers/misc/Makefile
> +++ b/drivers/misc/Makefile
> @@ -16,7 +16,6 @@ obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o
>  obj-$(CONFIG_TIFM_7XX1)       	+= tifm_7xx1.o
>  obj-$(CONFIG_PHANTOM)		+= phantom.o
>  obj-$(CONFIG_QCOM_COINCELL)	+= qcom-coincell.o
> -obj-$(CONFIG_QCOM_FASTRPC)	+= fastrpc.o
>  obj-$(CONFIG_SENSORS_BH1770)	+= bh1770glc.o
>  obj-$(CONFIG_SENSORS_APDS990X)	+= apds990x.o
>  obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
> @@ -69,3 +68,4 @@ obj-$(CONFIG_TMR_INJECT)	+= xilinx_tmr_inject.o
>  obj-$(CONFIG_TPS6594_ESM)	+= tps6594-esm.o
>  obj-$(CONFIG_TPS6594_PFSM)	+= tps6594-pfsm.o
>  obj-$(CONFIG_NSM)		+= nsm.o
> +obj-y				+= fastrpc/
> diff --git a/drivers/misc/fastrpc/Kconfig b/drivers/misc/fastrpc/Kconfig
> new file mode 100644
> index 000000000000..3243dc56b2a0
> --- /dev/null
> +++ b/drivers/misc/fastrpc/Kconfig
> @@ -0,0 +1,16 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +#
> +# Qualcomm FastRPC devices
> +#
> +
> +config QCOM_FASTRPC
> +	tristate "Qualcomm FastRPC"
> +	depends on ARCH_QCOM || COMPILE_TEST
> +	depends on RPMSG
> +	select DMA_SHARED_BUFFER
> +	select QCOM_SCM
> +	help
> +	  Provides a communication mechanism that allows for clients to
> +	  make remote method invocations across processor boundary to
> +	  applications DSP processor. Say M if you want to enable this
> +	  module.
> \ No newline at end of file
> diff --git a/drivers/misc/fastrpc/Makefile b/drivers/misc/fastrpc/Makefile
> new file mode 100644
> index 000000000000..77fd2b763b6b
> --- /dev/null
> +++ b/drivers/misc/fastrpc/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_QCOM_FASTRPC)	+= fastrpc.o
> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc/fastrpc.c
> similarity index 100%
> rename from drivers/misc/fastrpc.c
> rename to drivers/misc/fastrpc/fastrpc.c
> -- 
> 2.43.0
>
Greg KH June 19, 2024, 6:46 a.m. UTC | #2
On Wed, Jun 19, 2024 at 12:15:03PM +0530, Ekansh Gupta wrote:
> 
> 
> On 6/12/2024 11:58 PM, Dmitry Baryshkov wrote:
> > On Wed, Jun 12, 2024 at 12:17:28PM +0530, Ekansh Gupta wrote:
> >> Move fastrpc.c from misc/ to misc/fastrpc/. New C files are planned
> >> to be added for PD notifications and other missing features. Adding
> >> and maintaining new files from within fastrpc directory would be easy.
> >>
> >> Example of feature that is being planned to be introduced in a new C
> >> file:
> >> https://lore.kernel.org/all/20240606165939.12950-6-quic_ekangupt@quicinc.com/
> >>
> >> Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
> >> ---
> >>  MAINTAINERS                          |  2 +-
> >>  drivers/misc/Kconfig                 | 13 +------------
> >>  drivers/misc/Makefile                |  2 +-
> >>  drivers/misc/fastrpc/Kconfig         | 16 ++++++++++++++++
> >>  drivers/misc/fastrpc/Makefile        |  2 ++
> >>  drivers/misc/{ => fastrpc}/fastrpc.c |  0
> >>  6 files changed, 21 insertions(+), 14 deletions(-)
> >>  create mode 100644 drivers/misc/fastrpc/Kconfig
> >>  create mode 100644 drivers/misc/fastrpc/Makefile
> >>  rename drivers/misc/{ => fastrpc}/fastrpc.c (100%)
> > Please consider whether it makes sense to move to drivers/accel instead
> > (and possibly writing a better Kconfig entry, specifying that the driver
> > is to be used to offload execution to the DSP).
> Planning to keep the driver to misc/ only as part of this patch. Moving to accel/ might
> introduce some conventions to be followed which might require significant changes
> in driver.

Which is a good thing, please don't avoid this :)

thanks,

greg k-h
Ekansh Gupta June 19, 2024, 7 a.m. UTC | #3
On 6/19/2024 12:21 PM, Dmitry Baryshkov wrote:
> On Wed, 19 Jun 2024 at 09:45, Ekansh Gupta <quic_ekangupt@quicinc.com> wrote:
>>
>>
>> On 6/12/2024 11:58 PM, Dmitry Baryshkov wrote:
>>> On Wed, Jun 12, 2024 at 12:17:28PM +0530, Ekansh Gupta wrote:
>>>> Move fastrpc.c from misc/ to misc/fastrpc/. New C files are planned
>>>> to be added for PD notifications and other missing features. Adding
>>>> and maintaining new files from within fastrpc directory would be easy.
>>>>
>>>> Example of feature that is being planned to be introduced in a new C
>>>> file:
>>>> https://lore.kernel.org/all/20240606165939.12950-6-quic_ekangupt@quicinc.com/
>>>>
>>>> Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
>>>> ---
>>>>  MAINTAINERS                          |  2 +-
>>>>  drivers/misc/Kconfig                 | 13 +------------
>>>>  drivers/misc/Makefile                |  2 +-
>>>>  drivers/misc/fastrpc/Kconfig         | 16 ++++++++++++++++
>>>>  drivers/misc/fastrpc/Makefile        |  2 ++
>>>>  drivers/misc/{ => fastrpc}/fastrpc.c |  0
>>>>  6 files changed, 21 insertions(+), 14 deletions(-)
>>>>  create mode 100644 drivers/misc/fastrpc/Kconfig
>>>>  create mode 100644 drivers/misc/fastrpc/Makefile
>>>>  rename drivers/misc/{ => fastrpc}/fastrpc.c (100%)
>>> Please consider whether it makes sense to move to drivers/accel instead
>>> (and possibly writing a better Kconfig entry, specifying that the driver
>>> is to be used to offload execution to the DSP).
>> Planning to keep the driver to misc/ only as part of this patch. Moving to accel/ might
>> introduce some conventions to be followed which might require significant changes
>> in driver.
> To me this sounds like "we are trying to avoid following the
> conventions by hiding in the shadows".
Not trying to avoid, just trying to look into this separately as the need to take ABI also in account which
includes current device nodes and the uapi header which is present in uapi/misc/fastrpc.h whereas I see all
accel driver uapi headers are part of uapi/drm/.

Will be taking inputs from fastrpc maintainers also.
>> I'll write more meaningful Kconfig entry in next spin.
>>
Jeffrey Hugo June 21, 2024, 3:40 p.m. UTC | #4
On 6/21/2024 5:19 AM, Dmitry Baryshkov wrote:
> On Fri, 21 Jun 2024 at 09:19, Bjorn Andersson <andersson@kernel.org> wrote:
>>
>> On Wed, Jun 12, 2024 at 09:28:39PM GMT, Dmitry Baryshkov wrote:
>>> On Wed, Jun 12, 2024 at 12:17:28PM +0530, Ekansh Gupta wrote:
>>>> Move fastrpc.c from misc/ to misc/fastrpc/. New C files are planned
>>>> to be added for PD notifications and other missing features. Adding
>>>> and maintaining new files from within fastrpc directory would be easy.
>>>>
>>>> Example of feature that is being planned to be introduced in a new C
>>>> file:
>>>> https://lore.kernel.org/all/20240606165939.12950-6-quic_ekangupt@quicinc.com/
>>>>
>>>> Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
>>>> ---
>>>>   MAINTAINERS                          |  2 +-
>>>>   drivers/misc/Kconfig                 | 13 +------------
>>>>   drivers/misc/Makefile                |  2 +-
>>>>   drivers/misc/fastrpc/Kconfig         | 16 ++++++++++++++++
>>>>   drivers/misc/fastrpc/Makefile        |  2 ++
>>>>   drivers/misc/{ => fastrpc}/fastrpc.c |  0
>>>>   6 files changed, 21 insertions(+), 14 deletions(-)
>>>>   create mode 100644 drivers/misc/fastrpc/Kconfig
>>>>   create mode 100644 drivers/misc/fastrpc/Makefile
>>>>   rename drivers/misc/{ => fastrpc}/fastrpc.c (100%)
>>>
>>> Please consider whether it makes sense to move to drivers/accel instead
>>> (and possibly writing a better Kconfig entry, specifying that the driver
>>> is to be used to offload execution to the DSP).
>>>
>>
>> Wouldn't this come with the expectation of following the ABIs of
>> drivers/accel and thereby breaking userspace?
> 
> As I wrote earlier, that depends on the accel/ maintainers decision,
> whether it's acceptable to have non-DRM_ACCEL code underneath.
> But at least I'd try doing that on the grounds of keeping the code at
> the proper place in the drivers/ tree, raising awareness of the
> FastRPC, etc.
> For example current fastrpc driver bypasses dri-devel reviews, while
> if I remember correctly, at some point it was suggested that all
> dma-buf-handling drivers should also notify the dri-devel ML.
> 
> Also having the driver under drivers/accels makes it possible and
> logical to  implement DRM_ACCEL uAPI at some point. In the ideal world
> we should be able to declare existing FastRPC uAPI as legacy /
> deprecated / backwards compatibility only and migrate to the
> recommended uAPI approach, which is DRM_ACCEL.
> 

I suspect Vetter/Airlie need to be involved in this.

Its my understanding that accelerator drivers are able to reside in misc 
as long as there is no use of dma-buf.  Use of dma-buf means they need 
to be in drm/accel.

There is precedent for moving a driver from misc to accel (HabanaLabs).

Right now, I'm not aware that fastRPC meets the requirements for 
drm/accel.  There is an open source userspace driver, but I'm not aware 
of an open source compiler.  From what I know of the architecture, it 
should be possible to utilize upstream LLVM to produce one.

-Jeff
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index d6c90161c7bf..e9c79e9063f8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -18501,7 +18501,7 @@  M:	Amol Maheshwari <amahesh@qti.qualcomm.com>
 L:	linux-arm-msm@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml
-F:	drivers/misc/fastrpc.c
+F:	drivers/misc/fastrpc/
 F:	include/uapi/misc/fastrpc.h
 
 QUALCOMM HEXAGON ARCHITECTURE
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index faf983680040..630e8ccd8669 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -276,18 +276,6 @@  config QCOM_COINCELL
 	  to maintain PMIC register and RTC state in the absence of
 	  external power.
 
-config QCOM_FASTRPC
-	tristate "Qualcomm FastRPC"
-	depends on ARCH_QCOM || COMPILE_TEST
-	depends on RPMSG
-	select DMA_SHARED_BUFFER
-	select QCOM_SCM
-	help
-	  Provides a communication mechanism that allows for clients to
-	  make remote method invocations across processor boundary to
-	  applications DSP processor. Say M if you want to enable this
-	  module.
-
 config SGI_GRU
 	tristate "SGI GRU driver"
 	depends on X86_UV && SMP
@@ -602,4 +590,5 @@  source "drivers/misc/cardreader/Kconfig"
 source "drivers/misc/uacce/Kconfig"
 source "drivers/misc/pvpanic/Kconfig"
 source "drivers/misc/mchp_pci1xxxx/Kconfig"
+source "drivers/misc/fastrpc/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 153a3f4837e8..f83d73844ea5 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -16,7 +16,6 @@  obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o
 obj-$(CONFIG_TIFM_7XX1)       	+= tifm_7xx1.o
 obj-$(CONFIG_PHANTOM)		+= phantom.o
 obj-$(CONFIG_QCOM_COINCELL)	+= qcom-coincell.o
-obj-$(CONFIG_QCOM_FASTRPC)	+= fastrpc.o
 obj-$(CONFIG_SENSORS_BH1770)	+= bh1770glc.o
 obj-$(CONFIG_SENSORS_APDS990X)	+= apds990x.o
 obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
@@ -69,3 +68,4 @@  obj-$(CONFIG_TMR_INJECT)	+= xilinx_tmr_inject.o
 obj-$(CONFIG_TPS6594_ESM)	+= tps6594-esm.o
 obj-$(CONFIG_TPS6594_PFSM)	+= tps6594-pfsm.o
 obj-$(CONFIG_NSM)		+= nsm.o
+obj-y				+= fastrpc/
diff --git a/drivers/misc/fastrpc/Kconfig b/drivers/misc/fastrpc/Kconfig
new file mode 100644
index 000000000000..3243dc56b2a0
--- /dev/null
+++ b/drivers/misc/fastrpc/Kconfig
@@ -0,0 +1,16 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Qualcomm FastRPC devices
+#
+
+config QCOM_FASTRPC
+	tristate "Qualcomm FastRPC"
+	depends on ARCH_QCOM || COMPILE_TEST
+	depends on RPMSG
+	select DMA_SHARED_BUFFER
+	select QCOM_SCM
+	help
+	  Provides a communication mechanism that allows for clients to
+	  make remote method invocations across processor boundary to
+	  applications DSP processor. Say M if you want to enable this
+	  module.
\ No newline at end of file
diff --git a/drivers/misc/fastrpc/Makefile b/drivers/misc/fastrpc/Makefile
new file mode 100644
index 000000000000..77fd2b763b6b
--- /dev/null
+++ b/drivers/misc/fastrpc/Makefile
@@ -0,0 +1,2 @@ 
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_QCOM_FASTRPC)	+= fastrpc.o
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc/fastrpc.c
similarity index 100%
rename from drivers/misc/fastrpc.c
rename to drivers/misc/fastrpc/fastrpc.c