[PATCH 1/2] bus: imx-weim: optionally enable burst clock mode

[PATCH 1/2] bus: imx-weim: optionally enable burst clock mode

[Sven Van Asbroeck]

To enable burst clock mode, add the fsl,burst-clk-enable
property to the weim bus's devicetree node.

Example:
weim: weim@21b8000 {
	compatible = "fsl,imx6q-weim";
	reg = <0x021b8000 0x4000>;
	clocks = <&clks 196>;
	#address-cells = <2>;
	#size-cells = <1>;
	ranges = <0 0 0x08000000 0x08000000>;
	fsl,weim-cs-gpr = <&gpr>;
	fsl,burst-clk-enable;

	client-device@0,0 {
		compatible = "something";
		reg = <0 0 0x02000000>;
		#address-cells = <1>;
		#size-cells = <1>;
		bank-width = <2>;
		fsl,weim-cs-timing = <0x00620081 0x00000001 0x1c022000
				0x0000c000 0x1404a38e 0x00000000>;
	};
};

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
---
 drivers/bus/imx-weim.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c
index db74334ca5ef..cb7d5504a22a 100644
--- a/drivers/bus/imx-weim.c
+++ b/drivers/bus/imx-weim.c
@@ -19,6 +19,8 @@ struct imx_weim_devtype {
 	unsigned int	cs_count;
 	unsigned int	cs_regs_count;
 	unsigned int	cs_stride;
+	unsigned int	wcr_offset;
+	unsigned int	wcr_bcm;
 };
 
 static const struct imx_weim_devtype imx1_weim_devtype = {
@@ -37,6 +39,8 @@ static const struct imx_weim_devtype imx50_weim_devtype = {
 	.cs_count	= 4,
 	.cs_regs_count	= 6,
 	.cs_stride	= 0x18,
+	.wcr_offset	= 0x90,
+	.wcr_bcm	= BIT(0),
 };
 
 static const struct imx_weim_devtype imx51_weim_devtype = {
@@ -192,6 +196,7 @@ static int __init weim_parse_dt(struct platform_device *pdev,
 	struct device_node *child;
 	int ret, have_child = 0;
 	struct cs_timing_state ts = {};
+	u32 reg;
 
 	if (devtype == &imx50_weim_devtype) {
 		ret = imx_weim_gpr_setup(pdev);
@@ -199,6 +204,17 @@ static int __init weim_parse_dt(struct platform_device *pdev,
 			return ret;
 	}
 
+	if (of_property_read_bool(pdev->dev.of_node, "fsl,burst-clk-enable")) {
+		if (devtype->wcr_bcm) {
+			reg = readl(base + devtype->wcr_offset);
+			writel(reg | devtype->wcr_bcm,
+				base + devtype->wcr_offset);
+		} else {
+			dev_err(&pdev->dev, "burst clk mode not supported.\n");
+			return -EINVAL;
+		}
+	}
+
 	for_each_available_child_of_node(pdev->dev.of_node, child) {
 		ret = weim_timing_setup(&pdev->dev, child, base, devtype, &ts);
 		if (ret)
-- 
2.17.1

[PATCH 2/2] dt-bindings: bus: imx-weim: document optional burst clock mode

[Sven Van Asbroeck]

An optional devicetree property was added to the imx-weim driver,
which if present instructs it to operate in burst clock mode.
Update the dt-bindings to reflect this.

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
---
 Documentation/devicetree/bindings/bus/imx-weim.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/bus/imx-weim.txt b/Documentation/devicetree/bindings/bus/imx-weim.txt
index dda7d6d66479..1b1d1c5c21ea 100644
--- a/Documentation/devicetree/bindings/bus/imx-weim.txt
+++ b/Documentation/devicetree/bindings/bus/imx-weim.txt
@@ -44,6 +44,10 @@ Optional properties:
 			what bootloader sets up in IOMUXC_GPR1[11:0] will be
 			used.
 
+ - fsl,burst-clk-enable	For "fsl,imx50-weim" and "fsl,imx6q-weim" type of
+			devices, the presence of this property indicates that
+			the weim bus should operate in Burst Clock Mode.
+
 Timing property for child nodes. It is mandatory, not optional.
 
  - fsl,weim-cs-timing:	The timing array, contains timing values for the
-- 
2.17.1

Re: [PATCH 2/2] dt-bindings: bus: imx-weim: document optional burst clock mode

[Rob Herring]

On Fri, 12 Jul 2019 16:43:16 -0400, Sven Van Asbroeck wrote:
> An optional devicetree property was added to the imx-weim driver,
> which if present instructs it to operate in burst clock mode.
> Update the dt-bindings to reflect this.
> 
> Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
> ---
>  Documentation/devicetree/bindings/bus/imx-weim.txt | 4 ++++
>  1 file changed, 4 insertions(+)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH 1/2] bus: imx-weim: optionally enable burst clock mode

[Sven Van Asbroeck]

On Fri, Jul 12, 2019 at 4:43 PM Sven Van Asbroeck <thesven73@gmail.com> wrote:
>
> To enable burst clock mode, add the fsl,burst-clk-enable
> property to the weim bus's devicetree node.
>

Any feedback on this patch, positive or negative?

Re: [PATCH 1/2] bus: imx-weim: optionally enable burst clock mode

[Fabio Estevam]

Hi Sven,

On Thu, Jul 25, 2019 at 11:30 AM Sven Van Asbroeck <thesven73@gmail.com> wrote:
>
> On Fri, Jul 12, 2019 at 4:43 PM Sven Van Asbroeck <thesven73@gmail.com> wrote:
> >
> > To enable burst clock mode, add the fsl,burst-clk-enable
> > property to the weim bus's devicetree node.
> >
>
> Any feedback on this patch, positive or negative?

Looks good to me:

Reviewed-by: Fabio Estevam <festevam@gmail.com>

Re: [PATCH 1/2] bus: imx-weim: optionally enable burst clock mode

[Shawn Guo]

On Fri, Jul 12, 2019 at 04:43:15PM -0400, Sven Van Asbroeck wrote:
> To enable burst clock mode, add the fsl,burst-clk-enable
> property to the weim bus's devicetree node.
> 
> Example:
> weim: weim@21b8000 {
> 	compatible = "fsl,imx6q-weim";
> 	reg = <0x021b8000 0x4000>;
> 	clocks = <&clks 196>;
> 	#address-cells = <2>;
> 	#size-cells = <1>;
> 	ranges = <0 0 0x08000000 0x08000000>;
> 	fsl,weim-cs-gpr = <&gpr>;
> 	fsl,burst-clk-enable;
> 
> 	client-device@0,0 {
> 		compatible = "something";
> 		reg = <0 0 0x02000000>;
> 		#address-cells = <1>;
> 		#size-cells = <1>;
> 		bank-width = <2>;
> 		fsl,weim-cs-timing = <0x00620081 0x00000001 0x1c022000
> 				0x0000c000 0x1404a38e 0x00000000>;
> 	};
> };
> 
> Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>

Applied both, thanks.