[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

This are the missing device tree parts to add NAND support for i.MX 7.
See previous patchset:
https://lkml.org/lkml/2017/4/21/832

The previous version also included driver changes, which are already
merged.

--
Stefan

Changes since v2:
- Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
- Dropped driver changes, alreay merged

Changes since v1:
- Make clks_count const
- Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6

Stefan Agner (2):
  ARM: dts: imx7: add GPMI NAND
  ARM: dts: imx7-colibri: add NAND support

 arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
 arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

-- 
2.13.0

[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

This are the missing device tree parts to add NAND support for i.MX 7.
See previous patchset:
https://lkml.org/lkml/2017/4/21/832

The previous version also included driver changes, which are already
merged.

--
Stefan

Changes since v2:
- Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
- Dropped driver changes, alreay merged

Changes since v1:
- Make clks_count const
- Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6

Stefan Agner (2):
  ARM: dts: imx7: add GPMI NAND
  ARM: dts: imx7-colibri: add NAND support

 arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
 arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

-- 
2.13.0

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[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

This are the missing device tree parts to add NAND support for i.MX 7.
See previous patchset:
https://lkml.org/lkml/2017/4/21/832

The previous version also included driver changes, which are already
merged.

--
Stefan

Changes since v2:
- Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
- Dropped driver changes, alreay merged

Changes since v1:
- Make clks_count const
- Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6

Stefan Agner (2):
  ARM: dts: imx7: add GPMI NAND
  ARM: dts: imx7-colibri: add NAND support

 arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
 arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

-- 
2.13.0

[PATCH v3 1/2] ARM: dts: imx7: add GPMI NAND

[Stefan Agner]

Add i.MX 7 GPMI NAND module.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 arch/arm/boot/dts/imx7s.dtsi | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/arch/arm/boot/dts/imx7s.dtsi b/arch/arm/boot/dts/imx7s.dtsi
index c4f12fd2e044..89011b7dc7a0 100644
--- a/arch/arm/boot/dts/imx7s.dtsi
+++ b/arch/arm/boot/dts/imx7s.dtsi
@@ -995,5 +995,36 @@
 				status = "disabled";
 			};
 		};
+
+		dma_apbh: dma-apbh@33000000 {
+			compatible = "fsl,imx7d-dma-apbh", "fsl,imx28-dma-apbh";
+			reg = <0x33000000 0x2000>;
+			interrupts = <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "gpmi0", "gpmi1", "gpmi2", "gpmi3";
+			#dma-cells = <1>;
+			dma-channels = <4>;
+			clocks = <&clks IMX7D_NAND_USDHC_BUS_ROOT_CLK>,
+				<&clks IMX7D_NAND_ROOT_CLK>;
+			clock-names = "dma_apbh_bch", "dma_apbh_io";
+		};
+
+		gpmi: gpmi-nand@33002000{
+			compatible = "fsl,imx7d-gpmi-nand";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			reg = <0x33002000 0x2000>, <0x33004000 0x4000>;
+			reg-names = "gpmi-nand", "bch";
+			interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "bch";
+			clocks = <&clks IMX7D_NAND_ROOT_CLK>,
+				<&clks IMX7D_NAND_USDHC_BUS_ROOT_CLK>;
+			clock-names = "gpmi_io", "gpmi_bch_apb";
+			dmas = <&dma_apbh 0>;
+			dma-names = "rx-tx";
+			status = "disabled";
+		};
 	};
 };
-- 
2.13.0

[PATCH v3 1/2] ARM: dts: imx7: add GPMI NAND

[Stefan Agner]

Add i.MX 7 GPMI NAND module.

Signed-off-by: Stefan Agner <stefan-XLVq0VzYD2Y@public.gmane.org>
---
 arch/arm/boot/dts/imx7s.dtsi | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/arch/arm/boot/dts/imx7s.dtsi b/arch/arm/boot/dts/imx7s.dtsi
index c4f12fd2e044..89011b7dc7a0 100644
--- a/arch/arm/boot/dts/imx7s.dtsi
+++ b/arch/arm/boot/dts/imx7s.dtsi
@@ -995,5 +995,36 @@
 				status = "disabled";
 			};
 		};
+
+		dma_apbh: dma-apbh@33000000 {
+			compatible = "fsl,imx7d-dma-apbh", "fsl,imx28-dma-apbh";
+			reg = <0x33000000 0x2000>;
+			interrupts = <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "gpmi0", "gpmi1", "gpmi2", "gpmi3";
+			#dma-cells = <1>;
+			dma-channels = <4>;
+			clocks = <&clks IMX7D_NAND_USDHC_BUS_ROOT_CLK>,
+				<&clks IMX7D_NAND_ROOT_CLK>;
+			clock-names = "dma_apbh_bch", "dma_apbh_io";
+		};
+
+		gpmi: gpmi-nand@33002000{
+			compatible = "fsl,imx7d-gpmi-nand";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			reg = <0x33002000 0x2000>, <0x33004000 0x4000>;
+			reg-names = "gpmi-nand", "bch";
+			interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "bch";
+			clocks = <&clks IMX7D_NAND_ROOT_CLK>,
+				<&clks IMX7D_NAND_USDHC_BUS_ROOT_CLK>;
+			clock-names = "gpmi_io", "gpmi_bch_apb";
+			dmas = <&dma_apbh 0>;
+			dma-names = "rx-tx";
+			status = "disabled";
+		};
 	};
 };
-- 
2.13.0

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[PATCH v3 1/2] ARM: dts: imx7: add GPMI NAND

[Stefan Agner]

Add i.MX 7 GPMI NAND module.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 arch/arm/boot/dts/imx7s.dtsi | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/arch/arm/boot/dts/imx7s.dtsi b/arch/arm/boot/dts/imx7s.dtsi
index c4f12fd2e044..89011b7dc7a0 100644
--- a/arch/arm/boot/dts/imx7s.dtsi
+++ b/arch/arm/boot/dts/imx7s.dtsi
@@ -995,5 +995,36 @@
 				status = "disabled";
 			};
 		};
+
+		dma_apbh: dma-apbh at 33000000 {
+			compatible = "fsl,imx7d-dma-apbh", "fsl,imx28-dma-apbh";
+			reg = <0x33000000 0x2000>;
+			interrupts = <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "gpmi0", "gpmi1", "gpmi2", "gpmi3";
+			#dma-cells = <1>;
+			dma-channels = <4>;
+			clocks = <&clks IMX7D_NAND_USDHC_BUS_ROOT_CLK>,
+				<&clks IMX7D_NAND_ROOT_CLK>;
+			clock-names = "dma_apbh_bch", "dma_apbh_io";
+		};
+
+		gpmi: gpmi-nand at 33002000{
+			compatible = "fsl,imx7d-gpmi-nand";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			reg = <0x33002000 0x2000>, <0x33004000 0x4000>;
+			reg-names = "gpmi-nand", "bch";
+			interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "bch";
+			clocks = <&clks IMX7D_NAND_ROOT_CLK>,
+				<&clks IMX7D_NAND_USDHC_BUS_ROOT_CLK>;
+			clock-names = "gpmi_io", "gpmi_bch_apb";
+			dmas = <&dma_apbh 0>;
+			dma-names = "rx-tx";
+			status = "disabled";
+		};
 	};
 };
-- 
2.13.0

[PATCH v3 2/2] ARM: dts: imx7-colibri: add NAND support

[Stefan Agner]

The Colibri iMX7 modules come with 512MB on-module SLC NAND flash
populated. Make use of it by enabling the GPMI controller.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 arch/arm/boot/dts/imx7-colibri.dtsi | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm/boot/dts/imx7-colibri.dtsi b/arch/arm/boot/dts/imx7-colibri.dtsi
index 2d87489f9105..ad4ce19d455b 100644
--- a/arch/arm/boot/dts/imx7-colibri.dtsi
+++ b/arch/arm/boot/dts/imx7-colibri.dtsi
@@ -106,6 +106,15 @@
 	fsl,magic-packet;
 };
 
+&gpmi {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_gpmi_nand>;
+	fsl,use-minimum-ecc;
+	nand-on-flash-bbt;
+	nand-ecc-mode = "hw";
+	status = "okay";
+};
+
 &i2c1 {
 	clock-frequency = <100000>;
 	pinctrl-names = "default";
-- 
2.13.0

[PATCH v3 2/2] ARM: dts: imx7-colibri: add NAND support

[Stefan Agner]

The Colibri iMX7 modules come with 512MB on-module SLC NAND flash
populated. Make use of it by enabling the GPMI controller.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 arch/arm/boot/dts/imx7-colibri.dtsi | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm/boot/dts/imx7-colibri.dtsi b/arch/arm/boot/dts/imx7-colibri.dtsi
index 2d87489f9105..ad4ce19d455b 100644
--- a/arch/arm/boot/dts/imx7-colibri.dtsi
+++ b/arch/arm/boot/dts/imx7-colibri.dtsi
@@ -106,6 +106,15 @@
 	fsl,magic-packet;
 };
 
+&gpmi {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_gpmi_nand>;
+	fsl,use-minimum-ecc;
+	nand-on-flash-bbt;
+	nand-ecc-mode = "hw";
+	status = "okay";
+};
+
 &i2c1 {
 	clock-frequency = <100000>;
 	pinctrl-names = "default";
-- 
2.13.0

Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 02:20 PM, Stefan Agner wrote:
> This are the missing device tree parts to add NAND support for i.MX 7.
> See previous patchset:
> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>
> The previous version also included driver changes, which are already
> merged.
>
> --
> Stefan
>
> Changes since v2:
> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
Hi Stefan, sorry I didn't reply your last patch. I was unable to fully 
test on i.MX7 since the work bandwidth, but the quick test shows DMA 
cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check 
it tomorrow morning and let you know the result.
> - Dropped driver changes, alreay merged
>
> Changes since v1:
> - Make clks_count const
> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>
> Stefan Agner (2):
>    ARM: dts: imx7: add GPMI NAND
>    ARM: dts: imx7-colibri: add NAND support
>
>   arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>   arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>   2 files changed, 40 insertions(+)
>

Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 02:20 PM, Stefan Agner wrote:
> This are the missing device tree parts to add NAND support for i.MX 7.
> See previous patchset:
> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>
> The previous version also included driver changes, which are already
> merged.
>
> --
> Stefan
>
> Changes since v2:
> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
Hi Stefan, sorry I didn't reply your last patch. I was unable to fully 
test on i.MX7 since the work bandwidth, but the quick test shows DMA 
cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check 
it tomorrow morning and let you know the result.
> - Dropped driver changes, alreay merged
>
> Changes since v1:
> - Make clks_count const
> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>
> Stefan Agner (2):
>    ARM: dts: imx7: add GPMI NAND
>    ARM: dts: imx7-colibri: add NAND support
>
>   arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>   arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>   2 files changed, 40 insertions(+)
>
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Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 02:20 PM, Stefan Agner wrote:
> This are the missing device tree parts to add NAND support for i.MX 7.
> See previous patchset:
> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>
> The previous version also included driver changes, which are already
> merged.
>
> --
> Stefan
>
> Changes since v2:
> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
Hi Stefan, sorry I didn't reply your last patch. I was unable to fully 
test on i.MX7 since the work bandwidth, but the quick test shows DMA 
cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check 
it tomorrow morning and let you know the result.
> - Dropped driver changes, alreay merged
>
> Changes since v1:
> - Make clks_count const
> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>
> Stefan Agner (2):
>    ARM: dts: imx7: add GPMI NAND
>    ARM: dts: imx7-colibri: add NAND support
>
>   arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>   arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>   2 files changed, 40 insertions(+)
>

[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 02:20 PM, Stefan Agner wrote:
> This are the missing device tree parts to add NAND support for i.MX 7.
> See previous patchset:
> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>
> The previous version also included driver changes, which are already
> merged.
>
> --
> Stefan
>
> Changes since v2:
> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
Hi Stefan, sorry I didn't reply your last patch. I was unable to fully 
test on i.MX7 since the work bandwidth, but the quick test shows DMA 
cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check 
it tomorrow morning and let you know the result.
> - Dropped driver changes, alreay merged
>
> Changes since v1:
> - Make clks_count const
> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>
> Stefan Agner (2):
>    ARM: dts: imx7: add GPMI NAND
>    ARM: dts: imx7-colibri: add NAND support
>
>   arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>   arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>   2 files changed, 40 insertions(+)
>

Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

Hi Han,

On 2017-06-01 14:14, Han Xu wrote:
> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>> This are the missing device tree parts to add NAND support for i.MX 7.
>> See previous patchset:
>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>
>> The previous version also included driver changes, which are already
>> merged.
>>
>> --
>> Stefan
>>
>> Changes since v2:
>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully 
> test on i.MX7 since the work bandwidth, but the quick test shows DMA 
> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check 
> it tomorrow morning and let you know the result.

How did you test that?

Since DMA can only use NAND in i.MX 7, testing is somewhat hard.

Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT

mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT

md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR

This works for me.

I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
patchset applied...

Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
system seems stable.

All that said, this patchset v3 actually does not remove the
NAND_ROOT_CLK as intended to. Will send a v4.

--
Stefan

>> - Dropped driver changes, alreay merged
>>
>> Changes since v1:
>> - Make clks_count const
>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>
>> Stefan Agner (2):
>>    ARM: dts: imx7: add GPMI NAND
>>    ARM: dts: imx7-colibri: add NAND support
>>
>>   arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>   arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>   2 files changed, 40 insertions(+)
>>

Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

Hi Han,

On 2017-06-01 14:14, Han Xu wrote:
> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>> This are the missing device tree parts to add NAND support for i.MX 7.
>> See previous patchset:
>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>
>> The previous version also included driver changes, which are already
>> merged.
>>
>> --
>> Stefan
>>
>> Changes since v2:
>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully 
> test on i.MX7 since the work bandwidth, but the quick test shows DMA 
> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check 
> it tomorrow morning and let you know the result.

How did you test that?

Since DMA can only use NAND in i.MX 7, testing is somewhat hard.

Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT

mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT

md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR

This works for me.

I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
patchset applied...

Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
system seems stable.

All that said, this patchset v3 actually does not remove the
NAND_ROOT_CLK as intended to. Will send a v4.

--
Stefan

>> - Dropped driver changes, alreay merged
>>
>> Changes since v1:
>> - Make clks_count const
>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>
>> Stefan Agner (2):
>>    ARM: dts: imx7: add GPMI NAND
>>    ARM: dts: imx7-colibri: add NAND support
>>
>>   arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>   arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>   2 files changed, 40 insertions(+)
>>
--
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[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

Hi Han,

On 2017-06-01 14:14, Han Xu wrote:
> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>> This are the missing device tree parts to add NAND support for i.MX 7.
>> See previous patchset:
>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>
>> The previous version also included driver changes, which are already
>> merged.
>>
>> --
>> Stefan
>>
>> Changes since v2:
>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully 
> test on i.MX7 since the work bandwidth, but the quick test shows DMA 
> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check 
> it tomorrow morning and let you know the result.

How did you test that?

Since DMA can only use NAND in i.MX 7, testing is somewhat hard.

Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT

mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT

md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR

This works for me.

I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
patchset applied...

Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
system seems stable.

All that said, this patchset v3 actually does not remove the
NAND_ROOT_CLK as intended to. Will send a v4.

--
Stefan

>> - Dropped driver changes, alreay merged
>>
>> Changes since v1:
>> - Make clks_count const
>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>
>> Stefan Agner (2):
>>    ARM: dts: imx7: add GPMI NAND
>>    ARM: dts: imx7-colibri: add NAND support
>>
>>   arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>   arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>   2 files changed, 40 insertions(+)
>>

Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 08:48 PM, Stefan Agner wrote:
> Hi Han,
>
> On 2017-06-01 14:14, Han Xu wrote:
>> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>>> This are the missing device tree parts to add NAND support for i.MX 7.
>>> See previous patchset:
>>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>>
>>> The previous version also included driver changes, which are already
>>> merged.
>>>
>>> --
>>> Stefan
>>>
>>> Changes since v2:
>>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
>> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully
>> test on i.MX7 since the work bandwidth, but the quick test shows DMA
>> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check
>> it tomorrow morning and let you know the result.
> How did you test that?
>
> Since DMA can only use NAND in i.MX 7, testing is somewhat hard.
>
> Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT
>
> mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
> mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT

NAND_ROOT_CLK offset is 0x4140 which control the CCGR20 to gate on/off 
the rawnand module, including APBH/GPMI/BCH. Without enabling it, the 
mxs-dma hangs during initialization. I guess this bit was enabled in 
some early stage.

> md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR
>
> This works for me.
>
> I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
> patchset applied...
>
> Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
> NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
> system seems stable.
>
> All that said, this patchset v3 actually does not remove the
> NAND_ROOT_CLK as intended to. Will send a v4.
>
> --
> Stefan
>
>>> - Dropped driver changes, alreay merged
>>>
>>> Changes since v1:
>>> - Make clks_count const
>>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>>
>>> Stefan Agner (2):
>>>     ARM: dts: imx7: add GPMI NAND
>>>     ARM: dts: imx7-colibri: add NAND support
>>>
>>>    arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>>    arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>>    2 files changed, 40 insertions(+)
>>>

Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 08:48 PM, Stefan Agner wrote:
> Hi Han,
>
> On 2017-06-01 14:14, Han Xu wrote:
>> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>>> This are the missing device tree parts to add NAND support for i.MX 7.
>>> See previous patchset:
>>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>>
>>> The previous version also included driver changes, which are already
>>> merged.
>>>
>>> --
>>> Stefan
>>>
>>> Changes since v2:
>>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
>> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully
>> test on i.MX7 since the work bandwidth, but the quick test shows DMA
>> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check
>> it tomorrow morning and let you know the result.
> How did you test that?
>
> Since DMA can only use NAND in i.MX 7, testing is somewhat hard.
>
> Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT
>
> mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
> mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT

NAND_ROOT_CLK offset is 0x4140 which control the CCGR20 to gate on/off 
the rawnand module, including APBH/GPMI/BCH. Without enabling it, the 
mxs-dma hangs during initialization. I guess this bit was enabled in 
some early stage.

> md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR
>
> This works for me.
>
> I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
> patchset applied...
>
> Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
> NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
> system seems stable.
>
> All that said, this patchset v3 actually does not remove the
> NAND_ROOT_CLK as intended to. Will send a v4.
>
> --
> Stefan
>
>>> - Dropped driver changes, alreay merged
>>>
>>> Changes since v1:
>>> - Make clks_count const
>>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>>
>>> Stefan Agner (2):
>>>     ARM: dts: imx7: add GPMI NAND
>>>     ARM: dts: imx7-colibri: add NAND support
>>>
>>>    arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>>    arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>>    2 files changed, 40 insertions(+)
>>>
--
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Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 08:48 PM, Stefan Agner wrote:
> Hi Han,
>
> On 2017-06-01 14:14, Han Xu wrote:
>> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>>> This are the missing device tree parts to add NAND support for i.MX 7.
>>> See previous patchset:
>>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>>
>>> The previous version also included driver changes, which are already
>>> merged.
>>>
>>> --
>>> Stefan
>>>
>>> Changes since v2:
>>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
>> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully
>> test on i.MX7 since the work bandwidth, but the quick test shows DMA
>> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check
>> it tomorrow morning and let you know the result.
> How did you test that?
>
> Since DMA can only use NAND in i.MX 7, testing is somewhat hard.
>
> Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT
>
> mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
> mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT

NAND_ROOT_CLK offset is 0x4140 which control the CCGR20 to gate on/off 
the rawnand module, including APBH/GPMI/BCH. Without enabling it, the 
mxs-dma hangs during initialization. I guess this bit was enabled in 
some early stage.

> md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR
>
> This works for me.
>
> I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
> patchset applied...
>
> Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
> NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
> system seems stable.
>
> All that said, this patchset v3 actually does not remove the
> NAND_ROOT_CLK as intended to. Will send a v4.
>
> --
> Stefan
>
>>> - Dropped driver changes, alreay merged
>>>
>>> Changes since v1:
>>> - Make clks_count const
>>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>>
>>> Stefan Agner (2):
>>>     ARM: dts: imx7: add GPMI NAND
>>>     ARM: dts: imx7-colibri: add NAND support
>>>
>>>    arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>>    arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>>    2 files changed, 40 insertions(+)
>>>

[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Han Xu]

On 06/01/2017 08:48 PM, Stefan Agner wrote:
> Hi Han,
>
> On 2017-06-01 14:14, Han Xu wrote:
>> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>>> This are the missing device tree parts to add NAND support for i.MX 7.
>>> See previous patchset:
>>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>>
>>> The previous version also included driver changes, which are already
>>> merged.
>>>
>>> --
>>> Stefan
>>>
>>> Changes since v2:
>>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
>> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully
>> test on i.MX7 since the work bandwidth, but the quick test shows DMA
>> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check
>> it tomorrow morning and let you know the result.
> How did you test that?
>
> Since DMA can only use NAND in i.MX 7, testing is somewhat hard.
>
> Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT
>
> mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
> mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT

NAND_ROOT_CLK offset is 0x4140 which control the CCGR20 to gate on/off 
the rawnand module, including APBH/GPMI/BCH. Without enabling it, the 
mxs-dma hangs during initialization. I guess this bit was enabled in 
some early stage.

> md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR
>
> This works for me.
>
> I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
> patchset applied...
>
> Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
> NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
> system seems stable.
>
> All that said, this patchset v3 actually does not remove the
> NAND_ROOT_CLK as intended to. Will send a v4.
>
> --
> Stefan
>
>>> - Dropped driver changes, alreay merged
>>>
>>> Changes since v1:
>>> - Make clks_count const
>>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>>
>>> Stefan Agner (2):
>>>     ARM: dts: imx7: add GPMI NAND
>>>     ARM: dts: imx7-colibri: add NAND support
>>>
>>>    arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>>    arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>>    2 files changed, 40 insertions(+)
>>>

Re: [PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

On 2017-06-02 13:09, Han Xu wrote:
> On 06/01/2017 08:48 PM, Stefan Agner wrote:
>> Hi Han,
>>
>> On 2017-06-01 14:14, Han Xu wrote:
>>> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>>>> This are the missing device tree parts to add NAND support for i.MX 7.
>>>> See previous patchset:
>>>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>>>
>>>> The previous version also included driver changes, which are already
>>>> merged.
>>>>
>>>> --
>>>> Stefan
>>>>
>>>> Changes since v2:
>>>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
>>> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully
>>> test on i.MX7 since the work bandwidth, but the quick test shows DMA
>>> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check
>>> it tomorrow morning and let you know the result.
>> How did you test that?
>>
>> Since DMA can only use NAND in i.MX 7, testing is somewhat hard.
>>
>> Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT
>>
>> mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
>> mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT
> 
> NAND_ROOT_CLK offset is 0x4140 which control the CCGR20 to gate on/off 
> the rawnand module, including APBH/GPMI/BCH. Without enabling it, the 
> mxs-dma hangs during initialization. I guess this bit was enabled in 
> some early stage.

You are right, that clock gate was turned on, and it allowed access to
the APBH DMA.

However, while the gate was enabled, disabling the NAND_CLK_ROOT still
allowed to access APBH DMA, so the clock root itself is really not
required, but the gate is...

The clock which is required is NAND_USDHC_BUS_CLK_ROOT, but the gate is
part of NAND_CLK_ROOT. The clock tree is wrong: The gate is actually
shared, both clocks use the same gate.

In fact, assigning NAND_USDHC_BUS_CLK_ROOT directly to peripherals is
wrong since the gate is between the root clock and the peripherals (see
Figure 5-13 in RM). If we add the shared gate to NAND_USDHC_BUS_CLK_ROOT
directly, it will get enabled when using SDHC instances (since that root
clock is assigned to the sdhc instances, see
https://patchwork.kernel.org/patch/9674281/)

How about introducing NAND_USDHC_BUS_CLK_RAWNAND/NAND_CLK_RAWNAND which
has the shared gate in between?

--
Stefan

> 
>> md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR
>>
>> This works for me.
>>
>> I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
>> patchset applied...
>>
>> Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
>> NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
>> system seems stable.
>>
>> All that said, this patchset v3 actually does not remove the
>> NAND_ROOT_CLK as intended to. Will send a v4.
>>
>> --
>> Stefan
>>
>>>> - Dropped driver changes, alreay merged
>>>>
>>>> Changes since v1:
>>>> - Make clks_count const
>>>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>>>
>>>> Stefan Agner (2):
>>>>     ARM: dts: imx7: add GPMI NAND
>>>>     ARM: dts: imx7-colibri: add NAND support
>>>>
>>>>    arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>>>    arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>>>    2 files changed, 40 insertions(+)
>>>>

[PATCH v3 0/2] ARM: dts: imx7: add NAND support

[Stefan Agner]

On 2017-06-02 13:09, Han Xu wrote:
> On 06/01/2017 08:48 PM, Stefan Agner wrote:
>> Hi Han,
>>
>> On 2017-06-01 14:14, Han Xu wrote:
>>> On 06/01/2017 02:20 PM, Stefan Agner wrote:
>>>> This are the missing device tree parts to add NAND support for i.MX 7.
>>>> See previous patchset:
>>>> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2017%2F4%2F21%2F832&data=01%7C01%7Chan.xu%40nxp.com%7C3b9081a68c94476c4a2108d4a9235512%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0&sdata=mQ2aq5rW%2B9uADY5mSzFxk8P6bAVq%2BosPJQAi0PL9SQg%3D&reserved=0
>>>>
>>>> The previous version also included driver changes, which are already
>>>> merged.
>>>>
>>>> --
>>>> Stefan
>>>>
>>>> Changes since v2:
>>>> - Only specify IMX7D_NAND_USDHC_BUS_ROOT_CLK which seems to be sufficent
>>> Hi Stefan, sorry I didn't reply your last patch. I was unable to fully
>>> test on i.MX7 since the work bandwidth, but the quick test shows DMA
>>> cannot work WITHOUT IMX7D_NAND_ROOT_CLK on my side, I will fully check
>>> it tomorrow morning and let you know the result.
>> How did you test that?
>>
>> Since DMA can only use NAND in i.MX 7, testing is somewhat hard.
>>
>> Fact is, I can access DMA registers using just NAND_USDHC_BUS_CLK_ROOT
>>
>> mw.l 0x30388980 0x11000000 # Enable NAND_USDHC_BUS_CLK_ROOT
>> mw.l 0x3038aa00 0x00000000 # Enable NAND_CLK_ROOT
> 
> NAND_ROOT_CLK offset is 0x4140 which control the CCGR20 to gate on/off 
> the rawnand module, including APBH/GPMI/BCH. Without enabling it, the 
> mxs-dma hangs during initialization. I guess this bit was enabled in 
> some early stage.

You are right, that clock gate was turned on, and it allowed access to
the APBH DMA.

However, while the gate was enabled, disabling the NAND_CLK_ROOT still
allowed to access APBH DMA, so the clock root itself is really not
required, but the gate is...

The clock which is required is NAND_USDHC_BUS_CLK_ROOT, but the gate is
part of NAND_CLK_ROOT. The clock tree is wrong: The gate is actually
shared, both clocks use the same gate.

In fact, assigning NAND_USDHC_BUS_CLK_ROOT directly to peripherals is
wrong since the gate is between the root clock and the peripherals (see
Figure 5-13 in RM). If we add the shared gate to NAND_USDHC_BUS_CLK_ROOT
directly, it will get enabled when using SDHC instances (since that root
clock is assigned to the sdhc instances, see
https://patchwork.kernel.org/patch/9674281/)

How about introducing NAND_USDHC_BUS_CLK_RAWNAND/NAND_CLK_RAWNAND which
has the shared gate in between?

--
Stefan

> 
>> md.l 0x33000100 0 # Access APBH_CH0_CURCMDAR
>>
>> This works for me.
>>
>> I can *boot* from a UBIFS using this driver and Linux 4.12-rc1 with my
>> patchset applied...
>>
>> Monitoring clocks in /sys/kernel/debug/clk/clk_summary show that
>> NAND_ROOT_CLK gets turned off and back on if NAND access happens, the
>> system seems stable.
>>
>> All that said, this patchset v3 actually does not remove the
>> NAND_ROOT_CLK as intended to. Will send a v4.
>>
>> --
>> Stefan
>>
>>>> - Dropped driver changes, alreay merged
>>>>
>>>> Changes since v1:
>>>> - Make clks_count const
>>>> - Introduce IS_IMX7D for i.MX 7 SoC's and make it part of GPMI_IS_MX6
>>>>
>>>> Stefan Agner (2):
>>>>     ARM: dts: imx7: add GPMI NAND
>>>>     ARM: dts: imx7-colibri: add NAND support
>>>>
>>>>    arch/arm/boot/dts/imx7-colibri.dtsi |  9 +++++++++
>>>>    arch/arm/boot/dts/imx7s.dtsi        | 31 +++++++++++++++++++++++++++++++
>>>>    2 files changed, 40 insertions(+)
>>>>