diff mbox

[1/2] ARM: Exynos: replace custom MFC reserved memory handling with generic code

Message ID 1375705610-12724-2-git-send-email-m.szyprowski@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Marek Szyprowski Aug. 5, 2013, 12:26 p.m. UTC
MFC driver use custom bindings for managing reserved memory. Those bindings
are not really specific to MFC device and no even well discussed. They can
be easily replaced with generic, platform independent code for handling
reserved and contiguous memory.

Two additional child devices for each memory port (AXI master) are
introduced to let one assign some properties to each of them. Later one
can also use them to assign properties related to SYSMMU controllers,
which can be used to manage the limited dma window provided by those
memory ports.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 .../devicetree/bindings/media/s5p-mfc.txt          |   63 +++++++++++++++++---
 arch/arm/boot/dts/exynos4.dtsi                     |   10 +++-
 arch/arm/boot/dts/exynos4210-origen.dts            |   25 +++++++-
 arch/arm/boot/dts/exynos4210-smdkv310.dts          |   25 +++++++-
 arch/arm/boot/dts/exynos4412-origen.dts            |   25 +++++++-
 arch/arm/boot/dts/exynos4412-smdk4412.dts          |   25 +++++++-
 arch/arm/boot/dts/exynos5250-arndale.dts           |   26 +++++++-
 arch/arm/boot/dts/exynos5250-smdk5250.dts          |   26 +++++++-
 arch/arm/boot/dts/exynos5250.dtsi                  |   10 +++-
 arch/arm/mach-exynos/mach-exynos4-dt.c             |   16 -----
 arch/arm/mach-exynos/mach-exynos5-dt.c             |   17 ------
 arch/arm/plat-samsung/include/plat/mfc.h           |   11 ----
 arch/arm/plat-samsung/s5p-dev-mfc.c                |   32 ----------
 13 files changed, 212 insertions(+), 99 deletions(-)

Comments

Stephen Warren Aug. 8, 2013, 9 p.m. UTC | #1
On 08/05/2013 06:26 AM, Marek Szyprowski wrote:
> MFC driver use custom bindings for managing reserved memory. Those bindings
> are not really specific to MFC device and no even well discussed. They can
> be easily replaced with generic, platform independent code for handling
> reserved and contiguous memory.
> 
> Two additional child devices for each memory port (AXI master) are
> introduced to let one assign some properties to each of them. Later one
> can also use them to assign properties related to SYSMMU controllers,
> which can be used to manage the limited dma window provided by those
> memory ports.

> diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt b/Documentation/devicetree/bindings/media/s5p-mfc.txt

> +The MFC device is connected to system bus with two memory ports (AXI
> +masters) for better performance. Those memory ports are modelled as
> +separate child devices, so one can assign some properties to them (like
> +memory region for dma buffer allocation or sysmmu controller).
> +
>  Required properties:
>    - compatible : value should be either one among the following
>  	(a) "samsung,mfc-v5" for MFC v5 present in Exynos4 SoCs
>  	(b) "samsung,mfc-v6" for MFC v6 present in Exynos5 SoCs
> +	and additionally "simple-bus" to correctly initialize child
> +	devices for memory ports (AXI masters)

simple-bus is wrong here; the child nodes aren't independent entities
that can be instantiated separately from their parent and without
depending on their parent.

> -  - samsung,mfc-r : Base address of the first memory bank used by MFC
> -		    for DMA contiguous memory allocation and its size.
> -
> -  - samsung,mfc-l : Base address of the second memory bank used by MFC
> -		    for DMA contiguous memory allocation and its size.

These properties shouldn't be removed, but simply marked deprecated. The
driver will need to continue to support them so that old DTs work with
new kernels. The binding must therefore continue to document them so
that the old DT content still makes sense.

> +Two child nodes must be defined for MFC device. Their names must be
> +following: "memport-r" and "memport-l" ("right" and "left"). Required

Node names shouldn't have semantic meaning.

> +properties:
> +  - compatible : value should be "samsung,memport"

There's no need to define compatible properties for things which aren't
separate devices.

> +  - dma-memory-region : optional property with a phandle to respective memory
> +			region (see devicetree/bindings/memory.txt), if no region
> +			is defined, sysmmu controller must be used for managing
> +			limited dma window of each memory port.

What's the benefit of putting this property in a sub-node; surely you
can put the property in the main MFC node yet follow the same conceptual
schema for its content as a dma-memory-region node?
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Tomasz Figa Aug. 8, 2013, 9:19 p.m. UTC | #2
Hi Stephen,

On Thursday 08 of August 2013 15:00:52 Stephen Warren wrote:
> On 08/05/2013 06:26 AM, Marek Szyprowski wrote:
> > MFC driver use custom bindings for managing reserved memory. Those
> > bindings are not really specific to MFC device and no even well
> > discussed. They can be easily replaced with generic, platform
> > independent code for handling reserved and contiguous memory.
> > 
> > Two additional child devices for each memory port (AXI master) are
> > introduced to let one assign some properties to each of them. Later
> > one
> > can also use them to assign properties related to SYSMMU controllers,
> > which can be used to manage the limited dma window provided by those
> > memory ports.
> > 
> > diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt
> > b/Documentation/devicetree/bindings/media/s5p-mfc.txt
> > 
> > +The MFC device is connected to system bus with two memory ports (AXI
> > +masters) for better performance. Those memory ports are modelled as
> > +separate child devices, so one can assign some properties to them
> > (like +memory region for dma buffer allocation or sysmmu controller).
> > +
> > 
> >  Required properties:
> >    - compatible : value should be either one among the following
> >  	
> >  	(a) "samsung,mfc-v5" for MFC v5 present in Exynos4 SoCs
> >  	(b) "samsung,mfc-v6" for MFC v6 present in Exynos5 SoCs
> > 
> > +	and additionally "simple-bus" to correctly initialize child
> > +	devices for memory ports (AXI masters)
> 
> simple-bus is wrong here; the child nodes aren't independent entities
> that can be instantiated separately from their parent and without
> depending on their parent.

I fully agree, but I can't think of anything better. Could you suggest a 
solution that would cover our use case:

The MFC IP has two separate bus masters (called here and there memports). 
On some SoCs, each master must use different memory bank to meet memory 
bandwidth requirements for higher bitrate video streams. This can be seen 
as MFC having two DMA subdevices, which have different DMA windows.

On Linux, this is handled by binding two appropriate CMA memory regions to 
the memports, so the driver can do DMA allocations on behalf of particular 
memport and get appropriate memory for it.

> > -  - samsung,mfc-r : Base address of the first memory bank used by MFC
> > -		    for DMA contiguous memory allocation and its size.
> > -
> > -  - samsung,mfc-l : Base address of the second memory bank used by
> > MFC
> > -		    for DMA contiguous memory allocation and its size.
> 
> These properties shouldn't be removed, but simply marked deprecated. The
> driver will need to continue to support them so that old DTs work with
> new kernels. The binding must therefore continue to document them so
> that the old DT content still makes sense.

I tend to disagree on this. For Samsung platforms we've been trying to 
avoid DT bindings changes as much as possible, but I'd rather say that 
device tree was coupled with kernel version it came from, so Samsung-
specific bindings haven't been fully stabilized yet, especially since we 
are still at discussion stage when it's about defining processes for 
binding staging and stabilization.

I would rather see this patch as part of work on Samsung DT binding 
janitoring or maybe even sanitizing in some cases, like this one, when the 
old (and IMHO bad) MFC binding was introduced without proper review. I 
don't think we want to support this kind of brokenness anymore, especially 
considering the hacks which would be required by such support (see 
original implementation of this binding and code required in board file).

> > +Two child nodes must be defined for MFC device. Their names must be
> > +following: "memport-r" and "memport-l" ("right" and "left"). Required
> 
> Node names shouldn't have semantic meaning.

What about bus-master-0 and bus-master-1?

> > +properties:
> > +  - compatible : value should be "samsung,memport"
> 
> There's no need to define compatible properties for things which aren't
> separate devices.

I agree.

> > +  - dma-memory-region : optional property with a phandle to
> > respective memory +			region (see 
devicetree/bindings/memory.txt), if
> > no region
> > +			is defined, sysmmu controller must be used for 
managing
> > +			limited dma window of each memory port.
> 
> What's the benefit of putting this property in a sub-node; surely you
> can put the property in the main MFC node yet follow the same conceptual
> schema for its content as a dma-memory-region node?

See my use case description above.

Best regards,
Tomasz

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Stephen Warren Aug. 8, 2013, 9:47 p.m. UTC | #3
On 08/08/2013 03:19 PM, Tomasz Figa wrote:
> Hi Stephen,
> 
> On Thursday 08 of August 2013 15:00:52 Stephen Warren wrote:
>> On 08/05/2013 06:26 AM, Marek Szyprowski wrote:
>>> MFC driver use custom bindings for managing reserved memory. Those
>>> bindings are not really specific to MFC device and no even well
>>> discussed. They can be easily replaced with generic, platform
>>> independent code for handling reserved and contiguous memory.
>>>
>>> Two additional child devices for each memory port (AXI master) are
>>> introduced to let one assign some properties to each of them. Later
>>> one
>>> can also use them to assign properties related to SYSMMU controllers,
>>> which can be used to manage the limited dma window provided by those
>>> memory ports.
>>>
>>> diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt
>>> b/Documentation/devicetree/bindings/media/s5p-mfc.txt
>>>
>>> +The MFC device is connected to system bus with two memory ports (AXI
>>> +masters) for better performance. Those memory ports are modelled as
>>> +separate child devices, so one can assign some properties to them
>>> (like +memory region for dma buffer allocation or sysmmu controller).
>>> +
>>>
>>>  Required properties:
>>>    - compatible : value should be either one among the following
>>>  	
>>>  	(a) "samsung,mfc-v5" for MFC v5 present in Exynos4 SoCs
>>>  	(b) "samsung,mfc-v6" for MFC v6 present in Exynos5 SoCs
>>>
>>> +	and additionally "simple-bus" to correctly initialize child
>>> +	devices for memory ports (AXI masters)
>>
>> simple-bus is wrong here; the child nodes aren't independent entities
>> that can be instantiated separately from their parent and without
>> depending on their parent.
> 
> I fully agree, but I can't think of anything better. Could you suggest a 
> solution that would cover our use case:
> 
> The MFC IP has two separate bus masters (called here and there memports). 
> On some SoCs, each master must use different memory bank to meet memory 
> bandwidth requirements for higher bitrate video streams. This can be seen 
> as MFC having two DMA subdevices, which have different DMA windows.
> 
> On Linux, this is handled by binding two appropriate CMA memory regions to 
> the memports, so the driver can do DMA allocations on behalf of particular 
> memport and get appropriate memory for it.

I don't see what that has to do with simple-bus. Whatever parses the
node of the MFC can directly read from any contained property or child
node; there's no need to try and get the core DT tree parser to
enumerate the children.

If you actually need a struct platform_device for each of these child
nodes (which sounds wrong, but I'm not familiar with the code), then
simply have the driver call of_platform_populate() itself at the
appropriate time. But that's not going to work well unless the child
nodes have compatible values, which doesn't seem right given their purpose.

>>> -  - samsung,mfc-r : Base address of the first memory bank used by MFC
>>> -		    for DMA contiguous memory allocation and its size.
>>> -
>>> -  - samsung,mfc-l : Base address of the second memory bank used by
>>> MFC
>>> -		    for DMA contiguous memory allocation and its size.
>>
>> These properties shouldn't be removed, but simply marked deprecated. The
>> driver will need to continue to support them so that old DTs work with
>> new kernels. The binding must therefore continue to document them so
>> that the old DT content still makes sense.
> 
> I tend to disagree on this. For Samsung platforms we've been trying to 
> avoid DT bindings changes as much as possible, but I'd rather say that 
> device tree was coupled with kernel version it came from, so Samsung-
> specific bindings haven't been fully stabilized yet, especially since we 
> are still at discussion stage when it's about defining processes for 
> binding staging and stabilization.

Well, that's why everyone is shouting at ARM for abusing DT...

> I would rather see this patch as part of work on Samsung DT binding 
> janitoring or maybe even sanitizing in some cases, like this one, when the 
> old (and IMHO bad) MFC binding was introduced without proper review. I 
> don't think we want to support this kind of brokenness anymore, especially 
> considering the hacks which would be required by such support (see 
> original implementation of this binding and code required in board file).
> 
>>> +Two child nodes must be defined for MFC device. Their names must be
>>> +following: "memport-r" and "memport-l" ("right" and "left"). Required
>>
>> Node names shouldn't have semantic meaning.
> 
> What about bus-master-0 and bus-master-1?

Just "bus-master" for each might make sense. Use reg properties to
differentiate the two?
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Tomasz Figa Aug. 8, 2013, 10:10 p.m. UTC | #4
On Thursday 08 of August 2013 15:47:19 Stephen Warren wrote:
> On 08/08/2013 03:19 PM, Tomasz Figa wrote:
> > Hi Stephen,
> > 
> > On Thursday 08 of August 2013 15:00:52 Stephen Warren wrote:
> >> On 08/05/2013 06:26 AM, Marek Szyprowski wrote:
> >>> MFC driver use custom bindings for managing reserved memory. Those
> >>> bindings are not really specific to MFC device and no even well
> >>> discussed. They can be easily replaced with generic, platform
> >>> independent code for handling reserved and contiguous memory.
> >>> 
> >>> Two additional child devices for each memory port (AXI master) are
> >>> introduced to let one assign some properties to each of them. Later
> >>> one
> >>> can also use them to assign properties related to SYSMMU
> >>> controllers,
> >>> which can be used to manage the limited dma window provided by those
> >>> memory ports.
> >>> 
> >>> diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt
> >>> b/Documentation/devicetree/bindings/media/s5p-mfc.txt
> >>> 
> >>> +The MFC device is connected to system bus with two memory ports
> >>> (AXI
> >>> +masters) for better performance. Those memory ports are modelled as
> >>> +separate child devices, so one can assign some properties to them
> >>> (like +memory region for dma buffer allocation or sysmmu
> >>> controller).
> >>> +
> >>> 
> >>>  Required properties:
> >>>    - compatible : value should be either one among the following
> >>>  	
> >>>  	(a) "samsung,mfc-v5" for MFC v5 present in Exynos4 SoCs
> >>>  	(b) "samsung,mfc-v6" for MFC v6 present in Exynos5 SoCs
> >>> 
> >>> +	and additionally "simple-bus" to correctly initialize child
> >>> +	devices for memory ports (AXI masters)
> >> 
> >> simple-bus is wrong here; the child nodes aren't independent entities
> >> that can be instantiated separately from their parent and without
> >> depending on their parent.
> > 
> > I fully agree, but I can't think of anything better. Could you suggest
> > a solution that would cover our use case:
> > 
> > The MFC IP has two separate bus masters (called here and there
> > memports). On some SoCs, each master must use different memory bank
> > to meet memory bandwidth requirements for higher bitrate video
> > streams. This can be seen as MFC having two DMA subdevices, which
> > have different DMA windows.
> > 
> > On Linux, this is handled by binding two appropriate CMA memory
> > regions to the memports, so the driver can do DMA allocations on
> > behalf of particular memport and get appropriate memory for it.
> 
> I don't see what that has to do with simple-bus.

Well, this is not the first binding doing things this way, unless I don't 
understand something. See the recently posted mvebu bindings. Using 
simple-bus for this has the nice property of allowing both non-DT and DT 
cases to be handled in exactly the same way in MFC driver.

> Whatever parses the
> node of the MFC can directly read from any contained property or child
> node; there's no need to try and get the core DT tree parser to
> enumerate the children.
> 
> If you actually need a struct platform_device for each of these child
> nodes (which sounds wrong, but I'm not familiar with the code)

We need struct device for each memport and CMA region bound to both of 
them. This is a requirement of the Linux DMA mapping API, and well, it 
represents real hardware structure anyway.

> , then
> simply have the driver call of_platform_populate() itself at the
> appropriate time.

This sounds fine to me. 

> But that's not going to work well unless the child
> nodes have compatible values, which doesn't seem right given their
> purpose.
> >>> -  - samsung,mfc-r : Base address of the first memory bank used by
> >>> MFC
> >>> -		    for DMA contiguous memory allocation and its size.
> >>> -
> >>> -  - samsung,mfc-l : Base address of the second memory bank used by
> >>> MFC
> >>> -		    for DMA contiguous memory allocation and its size.
> >> 
> >> These properties shouldn't be removed, but simply marked deprecated.
> >> The driver will need to continue to support them so that old DTs
> >> work with new kernels. The binding must therefore continue to
> >> document them so that the old DT content still makes sense.
> > 
> > I tend to disagree on this. For Samsung platforms we've been trying to
> > avoid DT bindings changes as much as possible, but I'd rather say that
> > device tree was coupled with kernel version it came from, so Samsung-
> > specific bindings haven't been fully stabilized yet, especially since
> > we are still at discussion stage when it's about defining processes
> > for binding staging and stabilization.
> 
> Well, that's why everyone is shouting at ARM for abusing DT...

IMHO this is not fully fair. We have a lot of development happenning on 
ARM. Things usually can't be done perfectly on first iteration, while we 
often want things working reasonably ASAP.

This is why I'm really all for staging/stable separation. I believe things 
need to be tested in practice before we say that they are good already and 
can't be redone, which is what this kind of process would allow.

> > I would rather see this patch as part of work on Samsung DT binding
> > janitoring or maybe even sanitizing in some cases, like this one, when
> > the old (and IMHO bad) MFC binding was introduced without proper
> > review. I don't think we want to support this kind of brokenness
> > anymore, especially considering the hacks which would be required by
> > such support (see original implementation of this binding and code
> > required in board file).> 
> >>> +Two child nodes must be defined for MFC device. Their names must be
> >>> +following: "memport-r" and "memport-l" ("right" and "left").
> >>> Required
> >> 
> >> Node names shouldn't have semantic meaning.
> > 
> > What about bus-master-0 and bus-master-1?
> 
> Just "bus-master" for each might make sense. Use reg properties to
> differentiate the two?

What this reg property would mean in this case?

My understanding of reg property was that it should be used for real 
addresses or IDs and for all other cases node names should be suffixed 
with "-ID".

Best regards,
Tomasz

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Stephen Warren Aug. 8, 2013, 10:48 p.m. UTC | #5
On 08/08/2013 04:10 PM, Tomasz Figa wrote:
> On Thursday 08 of August 2013 15:47:19 Stephen Warren wrote:
>> On 08/08/2013 03:19 PM, Tomasz Figa wrote:
>>> On Thursday 08 of August 2013 15:00:52 Stephen Warren wrote:
>>>> On 08/05/2013 06:26 AM, Marek Szyprowski wrote:
>>>>> MFC driver use custom bindings for managing reserved memory. Those
>>>>> bindings are not really specific to MFC device and no even well
>>>>> discussed. They can be easily replaced with generic, platform
>>>>> independent code for handling reserved and contiguous memory.
>>>>>
>>>>> Two additional child devices for each memory port (AXI master) are
>>>>> introduced to let one assign some properties to each of them. Later
>>>>> one
>>>>> can also use them to assign properties related to SYSMMU
>>>>> controllers,
>>>>> which can be used to manage the limited dma window provided by those
>>>>> memory ports.
...
>>>>> +Two child nodes must be defined for MFC device. Their names must be
>>>>> +following: "memport-r" and "memport-l" ("right" and "left").
>>>>> Required
>>>>
>>>> Node names shouldn't have semantic meaning.
>>>
>>> What about bus-master-0 and bus-master-1?
>>
>> Just "bus-master" for each might make sense. Use reg properties to
>> differentiate the two?
> 
> What this reg property would mean in this case?
> 
> My understanding of reg property was that it should be used for real 
> addresses or IDs and for all other cases node names should be suffixed 
> with "-ID".

Presumably it would hold the ID of the HW block as defined in the
documentation. Or, it could be somewhat arbitrary.

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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt b/Documentation/devicetree/bindings/media/s5p-mfc.txt
index df37b02..d9528d4 100644
--- a/Documentation/devicetree/bindings/media/s5p-mfc.txt
+++ b/Documentation/devicetree/bindings/media/s5p-mfc.txt
@@ -6,10 +6,17 @@  The MFC device driver is a v4l2 driver which can encode/decode
 video raw/elementary streams and has support for all popular
 video codecs.
 
+The MFC device is connected to system bus with two memory ports (AXI
+masters) for better performance. Those memory ports are modelled as
+separate child devices, so one can assign some properties to them (like
+memory region for dma buffer allocation or sysmmu controller).
+
 Required properties:
   - compatible : value should be either one among the following
 	(a) "samsung,mfc-v5" for MFC v5 present in Exynos4 SoCs
 	(b) "samsung,mfc-v6" for MFC v6 present in Exynos5 SoCs
+	and additionally "simple-bus" to correctly initialize child
+	devices for memory ports (AXI masters)
 
   - reg : Physical base address of the IP registers and length of memory
 	  mapped region.
@@ -19,31 +26,69 @@  Required properties:
   - clock-names : from common clock binding: must contain "sclk_mfc" and "mfc",
 		  corresponding to entries in the clocks property.
 
-  - samsung,mfc-r : Base address of the first memory bank used by MFC
-		    for DMA contiguous memory allocation and its size.
-
-  - samsung,mfc-l : Base address of the second memory bank used by MFC
-		    for DMA contiguous memory allocation and its size.
-
 Optional properties:
   - samsung,power-domain : power-domain property defined with a phandle
 			   to respective power domain.
 
+Two child nodes must be defined for MFC device. Their names must be
+following: "memport-r" and "memport-l" ("right" and "left"). Required
+properties:
+  - compatible : value should be "samsung,memport"
+  - dma-memory-region : optional property with a phandle to respective memory
+			region (see devicetree/bindings/memory.txt), if no region
+			is defined, sysmmu controller must be used for managing
+			limited dma window of each memory port.
+
+
 Example:
 SoC specific DT entry:
 
 mfc: codec@13400000 {
-	compatible = "samsung,mfc-v5";
+	compatible = "samsung,mfc-v5", "simple-bus";
 	reg = <0x13400000 0x10000>;
 	interrupts = <0 94 0>;
 	samsung,power-domain = <&pd_mfc>;
 	clocks = <&clock 170>, <&clock 273>;
 	clock-names = "sclk_mfc", "mfc";
+	status = "disabled";
+
+	mfc_r: memport-r {
+		compatible = "samsung,memport";
+	};
+
+	mfc_l: memport-l {
+		compatible = "samsung,memport";
+	};
 };
 
 Board specific DT entry:
 
+memory {
+	/* ... */
+	reserved-memory {
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		mfc_l_mem: mfc_l_region@43000000 {
+			compatible = "contiguous-memory-region", "reserved-memory-region";
+			reg = <0x43000000 0x1000000>;
+		};
+
+		mfc_r_mem: mfc_r_region@52000000 {
+			compatible = "contiguous-memory-region", "reserved-memory-region";
+			reg = <0x52000000 0x1000000>;
+		};
+	};
+};
+
 codec@13400000 {
-	samsung,mfc-r = <0x43000000 0x800000>;
-	samsung,mfc-l = <0x51000000 0x800000>;
+	status = "okay";
+
+	memport-r {
+		dma-memory-region = <&mfc_r_mem>;
+	};
+
+	memport-l {
+		dma-memory-region = <&mfc_l_mem>;
+	};
 };
diff --git a/arch/arm/boot/dts/exynos4.dtsi b/arch/arm/boot/dts/exynos4.dtsi
index 3f94fe8..599637f 100644
--- a/arch/arm/boot/dts/exynos4.dtsi
+++ b/arch/arm/boot/dts/exynos4.dtsi
@@ -156,13 +156,21 @@ 
 	};
 
 	mfc: codec@13400000 {
-		compatible = "samsung,mfc-v5";
+		compatible = "samsung,mfc-v5", "simple-bus";
 		reg = <0x13400000 0x10000>;
 		interrupts = <0 94 0>;
 		samsung,power-domain = <&pd_mfc>;
 		clocks = <&clock 170>, <&clock 273>;
 		clock-names = "sclk_mfc", "mfc";
 		status = "disabled";
+
+		mfc_r: memport-r {
+			compatible = "samsung,memport";
+		};
+
+		mfc_l: memport-l {
+			compatible = "samsung,memport";
+		};
 	};
 
 	serial@13800000 {
diff --git a/arch/arm/boot/dts/exynos4210-origen.dts b/arch/arm/boot/dts/exynos4210-origen.dts
index 382d8c7..e80fe8a 100644
--- a/arch/arm/boot/dts/exynos4210-origen.dts
+++ b/arch/arm/boot/dts/exynos4210-origen.dts
@@ -26,6 +26,21 @@ 
 		       0x50000000 0x10000000
 		       0x60000000 0x10000000
 		       0x70000000 0x10000000>;
+
+		reserved-memory {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			mfc_l_mem: mfc_l_region@43000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x43000000 0x1000000>;
+			};
+
+			mfc_r_mem: mfc_r_region@51000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x51000000 0x1000000>;
+			};
+		};
 	};
 
 	chosen {
@@ -66,9 +81,15 @@ 
 	};
 
 	codec@13400000 {
-		samsung,mfc-r = <0x43000000 0x800000>;
-		samsung,mfc-l = <0x51000000 0x800000>;
 		status = "okay";
+
+		memport-r {
+			dma-memory-region = <&mfc_r_mem>;
+		};
+
+		memport-l {
+			dma-memory-region = <&mfc_l_mem>;
+		};
 	};
 
 	serial@13800000 {
diff --git a/arch/arm/boot/dts/exynos4210-smdkv310.dts b/arch/arm/boot/dts/exynos4210-smdkv310.dts
index 9c01b71..07adb56 100644
--- a/arch/arm/boot/dts/exynos4210-smdkv310.dts
+++ b/arch/arm/boot/dts/exynos4210-smdkv310.dts
@@ -23,6 +23,21 @@ 
 
 	memory {
 		reg = <0x40000000 0x80000000>;
+
+		reserved-memory {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			mfc_l_mem: mfc_l_region@43000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x43000000 0x1000000>;
+			};
+
+			mfc_r_mem: mfc_r_region@51000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x51000000 0x1000000>;
+			};
+		};
 	};
 
 	chosen {
@@ -41,9 +56,15 @@ 
 	};
 
 	codec@13400000 {
-		samsung,mfc-r = <0x43000000 0x800000>;
-		samsung,mfc-l = <0x51000000 0x800000>;
 		status = "okay";
+
+		memport-r {
+			dma-memory-region = <&mfc_r_mem>;
+		};
+
+		memport-l {
+			dma-memory-region = <&mfc_l_mem>;
+		};
 	};
 
 	serial@13800000 {
diff --git a/arch/arm/boot/dts/exynos4412-origen.dts b/arch/arm/boot/dts/exynos4412-origen.dts
index 7993641..1421070 100644
--- a/arch/arm/boot/dts/exynos4412-origen.dts
+++ b/arch/arm/boot/dts/exynos4412-origen.dts
@@ -21,6 +21,21 @@ 
 
 	memory {
 		reg = <0x40000000 0x40000000>;
+
+		reserved-memory {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			mfc_l_mem: mfc_l_region@43000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x43000000 0x1000000>;
+			};
+
+			mfc_r_mem: mfc_r_region@51000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x51000000 0x1000000>;
+			};
+		};
 	};
 
 	chosen {
@@ -133,9 +148,15 @@ 
 	};
 
 	codec@13400000 {
-		samsung,mfc-r = <0x43000000 0x800000>;
-		samsung,mfc-l = <0x51000000 0x800000>;
 		status = "okay";
+
+		memport-r {
+			dma-memory-region = <&mfc_r_mem>;
+		};
+
+		memport-l {
+			dma-memory-region = <&mfc_l_mem>;
+		};
 	};
 
 	fimd@11c00000 {
diff --git a/arch/arm/boot/dts/exynos4412-smdk4412.dts b/arch/arm/boot/dts/exynos4412-smdk4412.dts
index ad316a1..08a3735 100644
--- a/arch/arm/boot/dts/exynos4412-smdk4412.dts
+++ b/arch/arm/boot/dts/exynos4412-smdk4412.dts
@@ -21,6 +21,21 @@ 
 
 	memory {
 		reg = <0x40000000 0x40000000>;
+
+		reserved-memory {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			mfc_l_mem: mfc_l_region@43000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x43000000 0x1000000>;
+			};
+
+			mfc_r_mem: mfc_r_region@51000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x51000000 0x1000000>;
+			};
+		};
 	};
 
 	chosen {
@@ -126,9 +141,15 @@ 
 	};
 
 	codec@13400000 {
-		samsung,mfc-r = <0x43000000 0x800000>;
-		samsung,mfc-l = <0x51000000 0x800000>;
 		status = "okay";
+
+		memport-r {
+			dma-memory-region = <&mfc_r_mem>;
+		};
+
+		memport-l {
+			dma-memory-region = <&mfc_l_mem>;
+		};
 	};
 
 	serial@13800000 {
diff --git a/arch/arm/boot/dts/exynos5250-arndale.dts b/arch/arm/boot/dts/exynos5250-arndale.dts
index abc7272..ba4a533 100644
--- a/arch/arm/boot/dts/exynos5250-arndale.dts
+++ b/arch/arm/boot/dts/exynos5250-arndale.dts
@@ -18,6 +18,21 @@ 
 
 	memory {
 		reg = <0x40000000 0x80000000>;
+
+		reserved-memory {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			mfc_l_mem: mfc_l_region@43000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x43000000 0x1000000>;
+			};
+
+			mfc_r_mem: mfc_r_region@51000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x51000000 0x1000000>;
+			};
+		};
 	};
 
 	chosen {
@@ -25,8 +40,15 @@ 
 	};
 
 	codec@11000000 {
-		samsung,mfc-r = <0x43000000 0x800000>;
-		samsung,mfc-l = <0x51000000 0x800000>;
+		status = "okay";
+
+		memport-r {
+			dma-memory-region = <&mfc_r_mem>;
+		};
+
+		memport-l {
+			dma-memory-region = <&mfc_l_mem>;
+		};
 	};
 
 	i2c@12C60000 {
diff --git a/arch/arm/boot/dts/exynos5250-smdk5250.dts b/arch/arm/boot/dts/exynos5250-smdk5250.dts
index 49f18c2..daed15e 100644
--- a/arch/arm/boot/dts/exynos5250-smdk5250.dts
+++ b/arch/arm/boot/dts/exynos5250-smdk5250.dts
@@ -21,6 +21,21 @@ 
 
 	memory {
 		reg = <0x40000000 0x80000000>;
+
+		reserved-memory {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			mfc_l_mem: mfc_l_region@43000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x43000000 0x1000000>;
+			};
+
+			mfc_r_mem: mfc_r_region@51000000 {
+				compatible = "contiguous-memory-region", "reserved-memory-region";
+				reg = <0x51000000 0x1000000>;
+			};
+		};
 	};
 
 	chosen {
@@ -223,8 +238,15 @@ 
 	};
 
 	codec@11000000 {
-		samsung,mfc-r = <0x43000000 0x800000>;
-		samsung,mfc-l = <0x51000000 0x800000>;
+		status = "okay";
+
+		memport-r {
+			dma-memory-region = <&mfc_r_mem>;
+		};
+
+		memport-l {
+			dma-memory-region = <&mfc_l_mem>;
+		};
 	};
 
 	i2s0: i2s@03830000 {
diff --git a/arch/arm/boot/dts/exynos5250.dtsi b/arch/arm/boot/dts/exynos5250.dtsi
index ef57277..6011518 100644
--- a/arch/arm/boot/dts/exynos5250.dtsi
+++ b/arch/arm/boot/dts/exynos5250.dtsi
@@ -164,10 +164,18 @@ 
 	};
 
 	codec@11000000 {
-		compatible = "samsung,mfc-v6";
+		compatible = "samsung,mfc-v6", "simple-bus";
 		reg = <0x11000000 0x10000>;
 		interrupts = <0 96 0>;
 		samsung,power-domain = <&pd_mfc>;
+
+		mfc_r: memport-r {
+			compatible = "samsung,memport";
+		};
+
+		mfc_l: memport-l {
+			compatible = "samsung,memport";
+		};
 	};
 
 	rtc {
diff --git a/arch/arm/mach-exynos/mach-exynos4-dt.c b/arch/arm/mach-exynos/mach-exynos4-dt.c
index 0099c6c..0b6da39 100644
--- a/arch/arm/mach-exynos/mach-exynos4-dt.c
+++ b/arch/arm/mach-exynos/mach-exynos4-dt.c
@@ -13,13 +13,10 @@ 
 
 #include <linux/kernel.h>
 #include <linux/of_platform.h>
-#include <linux/of_fdt.h>
 #include <linux/serial_core.h>
-#include <linux/memblock.h>
 #include <linux/clocksource.h>
 
 #include <asm/mach/arch.h>
-#include <plat/mfc.h>
 
 #include "common.h"
 
@@ -35,18 +32,6 @@  static char const *exynos4_dt_compat[] __initdata = {
 	NULL
 };
 
-static void __init exynos4_reserve(void)
-{
-#ifdef CONFIG_S5P_DEV_MFC
-	struct s5p_mfc_dt_meminfo mfc_mem;
-
-	/* Reserve memory for MFC only if it's available */
-	mfc_mem.compatible = "samsung,mfc-v5";
-	if (of_scan_flat_dt(s5p_fdt_find_mfc_mem, &mfc_mem))
-		s5p_mfc_reserve_mem(mfc_mem.roff, mfc_mem.rsize, mfc_mem.loff,
-				mfc_mem.lsize);
-#endif
-}
 DT_MACHINE_START(EXYNOS4210_DT, "Samsung Exynos4 (Flattened Device Tree)")
 	/* Maintainer: Thomas Abraham <thomas.abraham@linaro.org> */
 	.smp		= smp_ops(exynos_smp_ops),
@@ -57,5 +42,4 @@  DT_MACHINE_START(EXYNOS4210_DT, "Samsung Exynos4 (Flattened Device Tree)")
 	.init_time	= exynos_init_time,
 	.dt_compat	= exynos4_dt_compat,
 	.restart        = exynos4_restart,
-	.reserve	= exynos4_reserve,
 MACHINE_END
diff --git a/arch/arm/mach-exynos/mach-exynos5-dt.c b/arch/arm/mach-exynos/mach-exynos5-dt.c
index f874b77..b5b0571 100644
--- a/arch/arm/mach-exynos/mach-exynos5-dt.c
+++ b/arch/arm/mach-exynos/mach-exynos5-dt.c
@@ -10,16 +10,13 @@ 
 */
 
 #include <linux/of_platform.h>
-#include <linux/of_fdt.h>
 #include <linux/memblock.h>
-#include <linux/io.h>
 #include <linux/clocksource.h>
 
 #include <asm/mach/arch.h>
 #include <mach/regs-pmu.h>
 
 #include <plat/cpu.h>
-#include <plat/mfc.h>
 
 #include "common.h"
 
@@ -57,19 +54,6 @@  static char const *exynos5_dt_compat[] __initdata = {
 	NULL
 };
 
-static void __init exynos5_reserve(void)
-{
-#ifdef CONFIG_S5P_DEV_MFC
-	struct s5p_mfc_dt_meminfo mfc_mem;
-
-	/* Reserve memory for MFC only if it's available */
-	mfc_mem.compatible = "samsung,mfc-v6";
-	if (of_scan_flat_dt(s5p_fdt_find_mfc_mem, &mfc_mem))
-		s5p_mfc_reserve_mem(mfc_mem.roff, mfc_mem.rsize, mfc_mem.loff,
-				mfc_mem.lsize);
-#endif
-}
-
 DT_MACHINE_START(EXYNOS5_DT, "SAMSUNG EXYNOS5 (Flattened Device Tree)")
 	/* Maintainer: Kukjin Kim <kgene.kim@samsung.com> */
 	.smp		= smp_ops(exynos_smp_ops),
@@ -79,5 +63,4 @@  DT_MACHINE_START(EXYNOS5_DT, "SAMSUNG EXYNOS5 (Flattened Device Tree)")
 	.init_time	= exynos_init_time,
 	.dt_compat	= exynos5_dt_compat,
 	.restart        = exynos5_restart,
-	.reserve	= exynos5_reserve,
 MACHINE_END
diff --git a/arch/arm/plat-samsung/include/plat/mfc.h b/arch/arm/plat-samsung/include/plat/mfc.h
index e6d7c42..ac13227 100644
--- a/arch/arm/plat-samsung/include/plat/mfc.h
+++ b/arch/arm/plat-samsung/include/plat/mfc.h
@@ -10,14 +10,6 @@ 
 #ifndef __PLAT_SAMSUNG_MFC_H
 #define __PLAT_SAMSUNG_MFC_H __FILE__
 
-struct s5p_mfc_dt_meminfo {
-	unsigned long	loff;
-	unsigned long	lsize;
-	unsigned long	roff;
-	unsigned long	rsize;
-	char		*compatible;
-};
-
 /**
  * s5p_mfc_reserve_mem - function to early reserve memory for MFC driver
  * @rbase:	base address for MFC 'right' memory interface
@@ -32,7 +24,4 @@  struct s5p_mfc_dt_meminfo {
 void __init s5p_mfc_reserve_mem(phys_addr_t rbase, unsigned int rsize,
 				phys_addr_t lbase, unsigned int lsize);
 
-int __init s5p_fdt_find_mfc_mem(unsigned long node, const char *uname,
-				int depth, void *data);
-
 #endif /* __PLAT_SAMSUNG_MFC_H */
diff --git a/arch/arm/plat-samsung/s5p-dev-mfc.c b/arch/arm/plat-samsung/s5p-dev-mfc.c
index ad51f85..f83be72 100644
--- a/arch/arm/plat-samsung/s5p-dev-mfc.c
+++ b/arch/arm/plat-samsung/s5p-dev-mfc.c
@@ -120,35 +120,3 @@  static int __init s5p_mfc_memory_init(void)
 }
 device_initcall(s5p_mfc_memory_init);
 #endif
-
-#ifdef CONFIG_OF
-int __init s5p_fdt_find_mfc_mem(unsigned long node, const char *uname,
-				int depth, void *data)
-{
-	__be32 *prop;
-	unsigned long len;
-	struct s5p_mfc_dt_meminfo *mfc_mem = data;
-
-	if (!data)
-		return 0;
-
-	if (!of_flat_dt_is_compatible(node, mfc_mem->compatible))
-		return 0;
-
-	prop = of_get_flat_dt_prop(node, "samsung,mfc-l", &len);
-	if (!prop || (len != 2 * sizeof(unsigned long)))
-		return 0;
-
-	mfc_mem->loff = be32_to_cpu(prop[0]);
-	mfc_mem->lsize = be32_to_cpu(prop[1]);
-
-	prop = of_get_flat_dt_prop(node, "samsung,mfc-r", &len);
-	if (!prop || (len != 2 * sizeof(unsigned long)))
-		return 0;
-
-	mfc_mem->roff = be32_to_cpu(prop[0]);
-	mfc_mem->rsize = be32_to_cpu(prop[1]);
-
-	return 1;
-}
-#endif