[PATCH v6 0/6] Add Qualcomm SM6115 / SM4250 EUD dt-bindings & driver support

[PATCH v6 0/6] Add Qualcomm SM6115 / SM4250 EUD dt-bindings & driver support

[Bhupesh Sharma]

Changes since v5:
----------------
- v5 can be viewed here: https://lore.kernel.org/linux-arm-msm/20230516213308.2432018-1-bhupesh.sharma@linaro.org/
- Addressed Mani's comment and added Fixes tag for [PATCH 1/6].
  Also collected his Ack for this patch.
- Fixed [PATCH 4/6] as per Greg's comments and added a separate patch
  for identation issues -> [PATCH 3/6].

Changes since v4:
----------------
- v4 can be viewed here: https://lore.kernel.org/linux-arm-msm/20230505064039.1630025-1-bhupesh.sharma@linaro.org/
- Addressed Konrad's review comments regarding EUD driver code.
- Also collected his R-B for [PATCH 4/5 and 5/5].
- Fixed the dt-bindings as per Krzysztof's comments.

Changes since v3:
----------------
- v3 can be viewed here: https://www.spinics.net/lists/linux-arm-msm/msg137025.html 
- Addressed Konrad's review comments regarding mainly the driver code.
  Also fixed the .dtsi as per his comments.
- Also collected his R-B for [PATCH 1/5].

Changes since v2:
----------------
- v2 can be viewed here: https://www.spinics.net/lists/linux-arm-msm/msg137025.html 
- Addressed Bjorn and Krzysztof's comments.
- Added [PATCH 1/5] which fixes the 'qcom_eud' sysfs path. 
- Added [PATCH 5/5] to enable EUD for Qualcomm QRB4210-RB2 boards.

Changes since v1:
----------------
- v1 can be viewed here: https://lore.kernel.org/linux-arm-msm/20221231130743.3285664-1-bhupesh.sharma@linaro.org
- Added Krzysztof in Cc list.
- Fixed the following issue reported by kernel test bot:
  >> ERROR: modpost: "qcom_scm_io_writel" [drivers/usb/misc/qcom_eud.ko] undefined!

This series adds the dt-binding and driver support for SM6115 / SM4250
EUD (Embedded USB Debugger) block available on Qualcomm SoCs.

It also enables the same for QRB4210-RB2 boards by default (the user
still needs to enable the same via sysfs).

The EUD is a mini-USB hub implemented on chip to support the USB-based debug
and trace capabilities.

EUD driver listens to events like USB attach or detach and then
informs the USB about these events via ROLE-SWITCH.

Bhupesh Sharma (6):
  usb: misc: eud: Fix eud sysfs path (use 'qcom_eud')
  dt-bindings: soc: qcom: eud: Add SM6115 / SM4250 support
  usb: misc: eud: Fix indentation issues
  usb: misc: eud: Add driver support for SM6115 / SM4250
  arm64: dts: qcom: sm6115: Add EUD dt node and dwc3 connector
  arm64: dts: qcom: qrb4210-rb2: Enable EUD debug peripheral

 Documentation/ABI/testing/sysfs-driver-eud    |  2 +-
 .../bindings/soc/qcom/qcom,eud.yaml           | 42 ++++++++++-
 arch/arm64/boot/dts/qcom/qrb4210-rb2.dts      | 27 +++++++-
 arch/arm64/boot/dts/qcom/sm6115.dtsi          | 50 ++++++++++++++
 drivers/usb/misc/Kconfig                      |  2 +-
 drivers/usb/misc/qcom_eud.c                   | 69 +++++++++++++++++--
 6 files changed, 179 insertions(+), 13 deletions(-)

-- 
2.38.1

[PATCH v6 1/6] usb: misc: eud: Fix eud sysfs path (use 'qcom_eud')

[Bhupesh Sharma]

The eud sysfs enablement path is currently mentioned in the
Documentation as:
  /sys/bus/platform/drivers/eud/.../enable

Instead it should be:
  /sys/bus/platform/drivers/qcom_eud/.../enable

Fix the same.

Fixes: 9a1bf58ccd44 ("usb: misc: eud: Add driver support for Embedded USB Debugger(EUD)")
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 Documentation/ABI/testing/sysfs-driver-eud | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-driver-eud b/Documentation/ABI/testing/sysfs-driver-eud
index 83f3872182a4..2bab0db2d2f0 100644
--- a/Documentation/ABI/testing/sysfs-driver-eud
+++ b/Documentation/ABI/testing/sysfs-driver-eud
@@ -1,4 +1,4 @@
-What:		/sys/bus/platform/drivers/eud/.../enable
+What:		/sys/bus/platform/drivers/qcom_eud/.../enable
 Date:           February 2022
 Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
 Description:
-- 
2.38.1

[PATCH v6 2/6] dt-bindings: soc: qcom: eud: Add SM6115 / SM4250 support

[Bhupesh Sharma]

Add dt-bindings for EUD found on Qualcomm SM6115 / SM4250 SoC.

On this SoC (and derivatives) the enable bit inside 'tcsr_check_reg'
needs to be set first to 'enable' the eud module.

So, update the dt-bindings to accommodate the third register
property (TCSR Base) required by the driver on these SoCs.

Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 .../bindings/soc/qcom/qcom,eud.yaml           | 42 +++++++++++++++++--
 1 file changed, 39 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
index f2c5ec7e6437..9c64b5d9504f 100644
--- a/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
@@ -18,12 +18,16 @@ properties:
     items:
       - enum:
           - qcom,sc7280-eud
+          - qcom,sm6115-eud
       - const: qcom,eud
 
   reg:
-    items:
-      - description: EUD Base Register Region
-      - description: EUD Mode Manager Register
+    minItems: 2
+    maxItems: 3
+
+  reg-names:
+    minItems: 2
+    maxItems: 3
 
   interrupts:
     description: EUD interrupt
@@ -52,6 +56,38 @@ required:
 
 additionalProperties: false
 
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - qcom,sc7280-eud
+    then:
+      properties:
+        reg:
+          maxItems: 2
+        reg-names:
+          items:
+            - const: eud-base
+            - const: eud-mode-mgr
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - qcom,sm6115-eud
+    then:
+      properties:
+        reg:
+          maxItems: 3
+        reg-names:
+          items:
+            - const: eud-base
+            - const: eud-mode-mgr
+            - const: tcsr-base
+
 examples:
   - |
     eud@88e0000 {
-- 
2.38.1

[PATCH v6 3/6] usb: misc: eud: Fix indentation issues

[Bhupesh Sharma]

Fix a couple of indentation issues in EUD driver.

Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 drivers/usb/misc/qcom_eud.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c
index b7f13df00764..74f2aeaccdcb 100644
--- a/drivers/usb/misc/qcom_eud.c
+++ b/drivers/usb/misc/qcom_eud.c
@@ -22,10 +22,10 @@
 #define EUD_REG_VBUS_INT_CLR	0x0080
 #define EUD_REG_CSR_EUD_EN	0x1014
 #define EUD_REG_SW_ATTACH_DET	0x1018
-#define EUD_REG_EUD_EN2        0x0000
+#define EUD_REG_EUD_EN2		0x0000
 
 #define EUD_ENABLE		BIT(0)
-#define EUD_INT_PET_EUD	BIT(0)
+#define EUD_INT_PET_EUD		BIT(0)
 #define EUD_INT_VBUS		BIT(2)
 #define EUD_INT_SAFE_MODE	BIT(4)
 #define EUD_INT_ALL		(EUD_INT_VBUS | EUD_INT_SAFE_MODE)
-- 
2.38.1

[PATCH v6 4/6] usb: misc: eud: Add driver support for SM6115 / SM4250

[Bhupesh Sharma]

Add SM6115 / SM4250 SoC EUD support in qcom_eud driver.

On some SoCs (like the SM6115 / SM4250 SoC), the mode manager
needs to be accessed only via the secure world (through 'scm'
calls).

Also, the enable bit inside 'tcsr_check_reg' needs to be set
first to set the eud in 'enable' mode on these SoCs.

Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 drivers/usb/misc/Kconfig    |  2 +-
 drivers/usb/misc/qcom_eud.c | 65 ++++++++++++++++++++++++++++++++++---
 2 files changed, 61 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig
index 99b15b77dfd5..51eb5140caa1 100644
--- a/drivers/usb/misc/Kconfig
+++ b/drivers/usb/misc/Kconfig
@@ -146,7 +146,7 @@ config USB_APPLEDISPLAY
 
 config USB_QCOM_EUD
 	tristate "QCOM Embedded USB Debugger(EUD) Driver"
-	depends on ARCH_QCOM || COMPILE_TEST
+	depends on (ARCH_QCOM && QCOM_SCM) || COMPILE_TEST
 	select USB_ROLE_SWITCH
 	help
 	  This module enables support for Qualcomm Technologies, Inc.
diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c
index 74f2aeaccdcb..6face21b7fb7 100644
--- a/drivers/usb/misc/qcom_eud.c
+++ b/drivers/usb/misc/qcom_eud.c
@@ -11,9 +11,11 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
+#include <linux/firmware/qcom/qcom_scm.h>
 #include <linux/usb/role.h>
 
 #define EUD_REG_INT1_EN_MASK	0x0024
@@ -30,15 +32,25 @@
 #define EUD_INT_SAFE_MODE	BIT(4)
 #define EUD_INT_ALL		(EUD_INT_VBUS | EUD_INT_SAFE_MODE)
 
+#define EUD_EN2_EN		BIT(0)
+#define EUD_EN2_DISABLE		(0)
+#define TCSR_CHECK_EN		BIT(0)
+
+struct eud_soc_cfg {
+	u32 tcsr_check_offset;
+};
+
 struct eud_chip {
 	struct device			*dev;
 	struct usb_role_switch		*role_sw;
+	const struct eud_soc_cfg	*eud_cfg;
 	void __iomem			*base;
 	void __iomem			*mode_mgr;
 	unsigned int			int_status;
 	int				irq;
 	bool				enabled;
 	bool				usb_attached;
+	phys_addr_t			secure_mode_mgr;
 };
 
 static int enable_eud(struct eud_chip *priv)
@@ -46,7 +58,11 @@ static int enable_eud(struct eud_chip *priv)
 	writel(EUD_ENABLE, priv->base + EUD_REG_CSR_EUD_EN);
 	writel(EUD_INT_VBUS | EUD_INT_SAFE_MODE,
 			priv->base + EUD_REG_INT1_EN_MASK);
-	writel(1, priv->mode_mgr + EUD_REG_EUD_EN2);
+
+	if (priv->secure_mode_mgr)
+		qcom_scm_io_writel(priv->secure_mode_mgr + EUD_REG_EUD_EN2, EUD_EN2_EN);
+	else
+		writel(EUD_EN2_EN, priv->mode_mgr + EUD_REG_EUD_EN2);
 
 	return usb_role_switch_set_role(priv->role_sw, USB_ROLE_DEVICE);
 }
@@ -54,7 +70,11 @@ static int enable_eud(struct eud_chip *priv)
 static void disable_eud(struct eud_chip *priv)
 {
 	writel(0, priv->base + EUD_REG_CSR_EUD_EN);
-	writel(0, priv->mode_mgr + EUD_REG_EUD_EN2);
+
+	if (priv->secure_mode_mgr)
+		qcom_scm_io_writel(priv->secure_mode_mgr + EUD_REG_EUD_EN2, EUD_EN2_DISABLE);
+	else
+		writel(EUD_EN2_DISABLE, priv->mode_mgr + EUD_REG_EUD_EN2);
 }
 
 static ssize_t enable_show(struct device *dev,
@@ -178,6 +198,8 @@ static void eud_role_switch_release(void *data)
 static int eud_probe(struct platform_device *pdev)
 {
 	struct eud_chip *chip;
+	struct resource *res;
+	phys_addr_t tcsr_check;
 	int ret;
 
 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
@@ -200,9 +222,37 @@ static int eud_probe(struct platform_device *pdev)
 	if (IS_ERR(chip->base))
 		return PTR_ERR(chip->base);
 
-	chip->mode_mgr = devm_platform_ioremap_resource(pdev, 1);
-	if (IS_ERR(chip->mode_mgr))
-		return PTR_ERR(chip->mode_mgr);
+	/*
+	 * EUD block on a few Qualcomm SoCs needs secure register access.
+	 * Check for the same.
+	 */
+	if (of_device_is_compatible(chip->dev->of_node, "qcom,sm6115-eud")) {
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+		if (!res)
+			return dev_err_probe(chip->dev, -ENODEV,
+					     "failed to get secure_mode_mgr reg base\n");
+
+		chip->secure_mode_mgr = res->start;
+	} else {
+		chip->mode_mgr = devm_platform_ioremap_resource(pdev, 1);
+		if (IS_ERR(chip->mode_mgr))
+			return PTR_ERR(chip->mode_mgr);
+	}
+
+	/* Check for any SoC specific config data */
+	chip->eud_cfg = of_device_get_match_data(&pdev->dev);
+	if (chip->eud_cfg) {
+		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "tcsr-base");
+		if (!res)
+			return dev_err_probe(chip->dev, -ENODEV,
+					     "failed to get tcsr reg base\n");
+
+		tcsr_check = res->start + chip->eud_cfg->tcsr_check_offset;
+
+		ret = qcom_scm_io_writel(tcsr_check, TCSR_CHECK_EN);
+		if (ret)
+			return dev_err_probe(chip->dev, ret, "failed to write tcsr check reg\n");
+	}
 
 	chip->irq = platform_get_irq(pdev, 0);
 	ret = devm_request_threaded_irq(&pdev->dev, chip->irq, handle_eud_irq,
@@ -230,8 +280,13 @@ static int eud_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct eud_soc_cfg sm6115_eud_cfg = {
+	.tcsr_check_offset = 0x25018,
+};
+
 static const struct of_device_id eud_dt_match[] = {
 	{ .compatible = "qcom,sc7280-eud" },
+	{ .compatible = "qcom,sm6115-eud", .data = &sm6115_eud_cfg },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, eud_dt_match);
-- 
2.38.1

[PATCH v6 5/6] arm64: dts: qcom: sm6115: Add EUD dt node and dwc3 connector

[Bhupesh Sharma]

Add the Embedded USB Debugger(EUD) device tree node for
SM6115 / SM4250 SoC.

The node contains EUD base register region, EUD mode manager
register region and TCSR Base register region along with the
interrupt entry.

Also add the typec connector node for EUD which is attached to
EUD node via port. EUD is also attached to DWC3 node via port.

To enable the role switch, we need to set dr_mode = "otg" property
for 'usb_dwc3' sub-node in the board dts file.

Also the EUD device can be enabled on a board once linux is boot'ed
by setting:
 $ echo 1 > /sys/bus/platform/drivers/qcom_eud/../enable

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 arch/arm64/boot/dts/qcom/sm6115.dtsi | 50 ++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sm6115.dtsi b/arch/arm64/boot/dts/qcom/sm6115.dtsi
index f67863561f3f..92a82d7172ca 100644
--- a/arch/arm64/boot/dts/qcom/sm6115.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm6115.dtsi
@@ -180,6 +180,18 @@ core3 {
 		};
 	};
 
+	eud_typec: connector {
+		compatible = "usb-c-connector";
+
+		ports {
+			port@0 {
+				con_eud: endpoint {
+					remote-endpoint = <&eud_con>;
+				};
+			};
+		};
+	};
+
 	firmware {
 		scm: scm {
 			compatible = "qcom,scm-sm6115", "qcom,scm";
@@ -647,6 +659,37 @@ gcc: clock-controller@1400000 {
 			#power-domain-cells = <1>;
 		};
 
+		eud: eud@1610000 {
+			compatible = "qcom,sm6115-eud", "qcom,eud";
+			reg = <0x0 0x01610000 0x0 0x2000>,
+			      <0x0 0x01612000 0x0 0x1000>,
+			      <0x0 0x003c0000 0x0 0x40000>;
+			reg-names = "eud-base", "eud-mode-mgr", "tcsr-base";
+			interrupts = <GIC_SPI 189 IRQ_TYPE_LEVEL_HIGH>;
+			status = "disabled";
+
+			ports {
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				port@0 {
+					reg = <0>;
+
+					eud_ep: endpoint {
+						remote-endpoint = <&usb2_role_switch>;
+					};
+				};
+
+				port@1 {
+					reg = <1>;
+
+					eud_con: endpoint {
+						remote-endpoint = <&con_eud>;
+					};
+				};
+			};
+		};
+
 		usb_hsphy: phy@1613000 {
 			compatible = "qcom,sm6115-qusb2-phy";
 			reg = <0x0 0x01613000 0x0 0x180>;
@@ -1144,6 +1187,13 @@ usb_dwc3: usb@4e00000 {
 				snps,has-lpm-erratum;
 				snps,hird-threshold = /bits/ 8 <0x10>;
 				snps,usb3_lpm_capable;
+				usb-role-switch;
+
+				port {
+					usb2_role_switch: endpoint {
+						remote-endpoint = <&eud_ep>;
+					};
+				};
 			};
 		};
 
-- 
2.38.1

[PATCH v6 6/6] arm64: dts: qcom: qrb4210-rb2: Enable EUD debug peripheral

[Bhupesh Sharma]

Since the USB-C type port on the Qualcomm QRB4210-RB2 board
can be set primarily in a 'device' configuration (with the default
DIP switch settings), it makes sense to enable the EUD debug
peripheral on the board by default by setting the USB 'dr_mode' property
as 'otg'.

Now, the EUD debug peripheral can be enabled by executing:
 $ echo 1 > /sys/bus/platform/drivers/qcom_eud/1610000.eud/enable

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 arch/arm64/boot/dts/qcom/qrb4210-rb2.dts | 27 +++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts b/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts
index 1a0776a0cfd0..0ce72f1ebc10 100644
--- a/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts
+++ b/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts
@@ -30,6 +30,10 @@ vph_pwr: vph-pwr-regulator {
 	};
 };
 
+&eud {
+	status = "okay";
+};
+
 &qupv3_id_0 {
 	status = "okay";
 };
@@ -253,7 +257,28 @@ &usb {
 
 &usb_dwc3 {
 	maximum-speed = "super-speed";
-	dr_mode = "peripheral";
+
+	/*
+	 * There is only one USB DWC3 controller on QRB4210 board and it is connected
+	 * via a DIP Switch:
+	 * - to either an USB - C type connector or an USB - A type connector
+	 *   (via a GL3590-S hub), and
+	 * - to either an USB - A type connector (via a GL3590-S hub) or a connector
+	 *   for further connection with a mezzanine board.
+	 *
+	 * All of the above hardware muxes would allow us to hook things up in
+	 * different ways to some potential benefit for static configurations (for e.g.
+	 * on one hand we can have two USB - A type connectors and a USB - Ethernet
+	 * connection available and on the other we can use the USB - C type in
+	 * peripheral mode).
+	 *
+	 * Note that since the USB - C type can be used only in peripehral mode,
+	 * so hardcoding the mode to 'peripheral' here makes sense.
+	 *
+	 * However since we want to use the EUD debug device, we set the mode as
+	 * 'otg' here.
+	 */
+	dr_mode = "otg";
 };
 
 &usb_hsphy {
-- 
2.38.1

Re: [PATCH v6 2/6] dt-bindings: soc: qcom: eud: Add SM6115 / SM4250 support

[Krzysztof Kozlowski]

On 17/05/2023 23:17, Bhupesh Sharma wrote:
> Add dt-bindings for EUD found on Qualcomm SM6115 / SM4250 SoC.
> 
> On this SoC (and derivatives) the enable bit inside 'tcsr_check_reg'
> needs to be set first to 'enable' the eud module.
> 
> So, update the dt-bindings to accommodate the third register
> property (TCSR Base) required by the driver on these SoCs.
> 
> Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>

This is a friendly reminder during the review process.

It looks like you received a tag and forgot to add it.

If you do not know the process, here is a short explanation:
Please add Acked-by/Reviewed-by/Tested-by tags when posting new
versions. However, there's no need to repost patches *only* to add the
tags. The upstream maintainer will do that for acks received on the
version they apply.

https://elixir.bootlin.com/linux/v5.17/source/Documentation/process/submitting-patches.rst#L540

If a tag was not added on purpose, please state why and what changed.

Also - no improvements.

Best regards,
Krzysztof

Re: [PATCH v6 2/6] dt-bindings: soc: qcom: eud: Add SM6115 / SM4250 support

[Bhupesh Sharma]

Hi Krzysztof,

On Thu, 18 May 2023 at 13:08, Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
>
> On 17/05/2023 23:17, Bhupesh Sharma wrote:
> > Add dt-bindings for EUD found on Qualcomm SM6115 / SM4250 SoC.
> >
> > On this SoC (and derivatives) the enable bit inside 'tcsr_check_reg'
> > needs to be set first to 'enable' the eud module.
> >
> > So, update the dt-bindings to accommodate the third register
> > property (TCSR Base) required by the driver on these SoCs.
> >
> > Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
>
> This is a friendly reminder during the review process.
>
> It looks like you received a tag and forgot to add it.
>
> If you do not know the process, here is a short explanation:
> Please add Acked-by/Reviewed-by/Tested-by tags when posting new
> versions. However, there's no need to repost patches *only* to add the
> tags. The upstream maintainer will do that for acks received on the
> version they apply.
>
> https://elixir.bootlin.com/linux/v5.17/source/Documentation/process/submitting-patches.rst#L540
>
> If a tag was not added on purpose, please state why and what changed.
>
> Also - no improvements.

Oops, seems I missed your review on v5 due to a label filter for
'linux-usb' list.
I will take care in future versions.

Please let me know if the R-B tag is still valid though :)

Thanks.

Re: [PATCH v6 4/6] usb: misc: eud: Add driver support for SM6115 / SM4250

[Konrad Dybcio]

On 17.05.2023 23:17, Bhupesh Sharma wrote:
> Add SM6115 / SM4250 SoC EUD support in qcom_eud driver.
> 
> On some SoCs (like the SM6115 / SM4250 SoC), the mode manager
> needs to be accessed only via the secure world (through 'scm'
> calls).
> 
> Also, the enable bit inside 'tcsr_check_reg' needs to be set
> first to set the eud in 'enable' mode on these SoCs.
> 
> Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
> ---
>  drivers/usb/misc/Kconfig    |  2 +-
>  drivers/usb/misc/qcom_eud.c | 65 ++++++++++++++++++++++++++++++++++---
>  2 files changed, 61 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig
> index 99b15b77dfd5..51eb5140caa1 100644
> --- a/drivers/usb/misc/Kconfig
> +++ b/drivers/usb/misc/Kconfig
> @@ -146,7 +146,7 @@ config USB_APPLEDISPLAY
>  
>  config USB_QCOM_EUD
>  	tristate "QCOM Embedded USB Debugger(EUD) Driver"
> -	depends on ARCH_QCOM || COMPILE_TEST
> +	depends on (ARCH_QCOM && QCOM_SCM) || COMPILE_TEST
>  	select USB_ROLE_SWITCH
>  	help
>  	  This module enables support for Qualcomm Technologies, Inc.
> diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c
> index 74f2aeaccdcb..6face21b7fb7 100644
> --- a/drivers/usb/misc/qcom_eud.c
> +++ b/drivers/usb/misc/qcom_eud.c
> @@ -11,9 +11,11 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> +#include <linux/of_device.h>
>  #include <linux/platform_device.h>
>  #include <linux/slab.h>
>  #include <linux/sysfs.h>
> +#include <linux/firmware/qcom/qcom_scm.h>
>  #include <linux/usb/role.h>
>  
>  #define EUD_REG_INT1_EN_MASK	0x0024
> @@ -30,15 +32,25 @@
>  #define EUD_INT_SAFE_MODE	BIT(4)
>  #define EUD_INT_ALL		(EUD_INT_VBUS | EUD_INT_SAFE_MODE)
>  
> +#define EUD_EN2_EN		BIT(0)
> +#define EUD_EN2_DISABLE		(0)
> +#define TCSR_CHECK_EN		BIT(0)
> +
> +struct eud_soc_cfg {
> +	u32 tcsr_check_offset;
> +};
> +
>  struct eud_chip {
>  	struct device			*dev;
>  	struct usb_role_switch		*role_sw;
> +	const struct eud_soc_cfg	*eud_cfg;
>  	void __iomem			*base;
>  	void __iomem			*mode_mgr;
>  	unsigned int			int_status;
>  	int				irq;
>  	bool				enabled;
>  	bool				usb_attached;
> +	phys_addr_t			secure_mode_mgr;
>  };
>  
>  static int enable_eud(struct eud_chip *priv)
> @@ -46,7 +58,11 @@ static int enable_eud(struct eud_chip *priv)
>  	writel(EUD_ENABLE, priv->base + EUD_REG_CSR_EUD_EN);
>  	writel(EUD_INT_VBUS | EUD_INT_SAFE_MODE,
>  			priv->base + EUD_REG_INT1_EN_MASK);
> -	writel(1, priv->mode_mgr + EUD_REG_EUD_EN2);
> +
> +	if (priv->secure_mode_mgr)
> +		qcom_scm_io_writel(priv->secure_mode_mgr + EUD_REG_EUD_EN2, EUD_EN2_EN);
> +	else
> +		writel(EUD_EN2_EN, priv->mode_mgr + EUD_REG_EUD_EN2);
>  
>  	return usb_role_switch_set_role(priv->role_sw, USB_ROLE_DEVICE);
>  }
> @@ -54,7 +70,11 @@ static int enable_eud(struct eud_chip *priv)
>  static void disable_eud(struct eud_chip *priv)
>  {
>  	writel(0, priv->base + EUD_REG_CSR_EUD_EN);
> -	writel(0, priv->mode_mgr + EUD_REG_EUD_EN2);
> +
> +	if (priv->secure_mode_mgr)
> +		qcom_scm_io_writel(priv->secure_mode_mgr + EUD_REG_EUD_EN2, EUD_EN2_DISABLE);
> +	else
> +		writel(EUD_EN2_DISABLE, priv->mode_mgr + EUD_REG_EUD_EN2);
>  }
>  
>  static ssize_t enable_show(struct device *dev,
> @@ -178,6 +198,8 @@ static void eud_role_switch_release(void *data)
>  static int eud_probe(struct platform_device *pdev)
>  {
>  	struct eud_chip *chip;
> +	struct resource *res;
> +	phys_addr_t tcsr_check;
>  	int ret;
>  
>  	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
> @@ -200,9 +222,37 @@ static int eud_probe(struct platform_device *pdev)
>  	if (IS_ERR(chip->base))
>  		return PTR_ERR(chip->base);
>  
> -	chip->mode_mgr = devm_platform_ioremap_resource(pdev, 1);
> -	if (IS_ERR(chip->mode_mgr))
> -		return PTR_ERR(chip->mode_mgr);
> +	/*
> +	 * EUD block on a few Qualcomm SoCs needs secure register access.
> +	 * Check for the same.
> +	 */
> +	if (of_device_is_compatible(chip->dev->of_node, "qcom,sm6115-eud")) {
I didn't notice that this changed between v4 and v5, but in my v4 review
I suggested using

if (of_property_read_bool(chip->dev->of_node, "qcom,secure-mode-enable"))

as this was the only place where the value of that function was checked
and caching it in the driver struct simply made no sense (as of today, anyway)

checking the device compatible does not scale very well for something
generic, as now it'd require adding each qcom,smABCD-eud to this condition
as well.

> +		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +		if (!res)
> +			return dev_err_probe(chip->dev, -ENODEV,
> +					     "failed to get secure_mode_mgr reg base\n");
This suggests the reg-name is "secure_mode_mgr" which is not true,
according to your binding patch. I thought about adding a separate
entry, but ultimately this would be against the DT philosophy, as it
references the same physical region as "eud-mode-mgr", just that due
to ACL software running at a higher exception level it's not
directly accessible..

I was debating suggesting moving it to SoC configuration, but that
also depends on the software stack (e.g. there are windows and cros
7280 laptops with different security restrictions).. so I think
the dt property is the way to go.

Konrad
> +
> +		chip->secure_mode_mgr = res->start;
> +	} else {
> +		chip->mode_mgr = devm_platform_ioremap_resource(pdev, 1);
> +		if (IS_ERR(chip->mode_mgr))
> +			return PTR_ERR(chip->mode_mgr);
> +	}
> +
> +	/* Check for any SoC specific config data */
> +	chip->eud_cfg = of_device_get_match_data(&pdev->dev);
> +	if (chip->eud_cfg) {
> +		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "tcsr-base");
> +		if (!res)
> +			return dev_err_probe(chip->dev, -ENODEV,
> +					     "failed to get tcsr reg base\n");
> +
> +		tcsr_check = res->start + chip->eud_cfg->tcsr_check_offset;
> +
> +		ret = qcom_scm_io_writel(tcsr_check, TCSR_CHECK_EN);
> +		if (ret)
> +			return dev_err_probe(chip->dev, ret, "failed to write tcsr check reg\n");
> +	}
>  
>  	chip->irq = platform_get_irq(pdev, 0);
>  	ret = devm_request_threaded_irq(&pdev->dev, chip->irq, handle_eud_irq,
> @@ -230,8 +280,13 @@ static int eud_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static const struct eud_soc_cfg sm6115_eud_cfg = {
> +	.tcsr_check_offset = 0x25018,
> +};
> +
>  static const struct of_device_id eud_dt_match[] = {
>  	{ .compatible = "qcom,sc7280-eud" },
> +	{ .compatible = "qcom,sm6115-eud", .data = &sm6115_eud_cfg },
>  	{ }
>  };
>  MODULE_DEVICE_TABLE(of, eud_dt_match);

Re: [PATCH v6 4/6] usb: misc: eud: Add driver support for SM6115 / SM4250

[Bhupesh Sharma]

On Thu, 18 May 2023 at 15:58, Konrad Dybcio <konrad.dybcio@linaro.org> wrote:
>
> On 17.05.2023 23:17, Bhupesh Sharma wrote:
> > Add SM6115 / SM4250 SoC EUD support in qcom_eud driver.
> >
> > On some SoCs (like the SM6115 / SM4250 SoC), the mode manager
> > needs to be accessed only via the secure world (through 'scm'
> > calls).
> >
> > Also, the enable bit inside 'tcsr_check_reg' needs to be set
> > first to set the eud in 'enable' mode on these SoCs.
> >
> > Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
> > ---
> >  drivers/usb/misc/Kconfig    |  2 +-
> >  drivers/usb/misc/qcom_eud.c | 65 ++++++++++++++++++++++++++++++++++---
> >  2 files changed, 61 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig
> > index 99b15b77dfd5..51eb5140caa1 100644
> > --- a/drivers/usb/misc/Kconfig
> > +++ b/drivers/usb/misc/Kconfig
> > @@ -146,7 +146,7 @@ config USB_APPLEDISPLAY
> >
> >  config USB_QCOM_EUD
> >       tristate "QCOM Embedded USB Debugger(EUD) Driver"
> > -     depends on ARCH_QCOM || COMPILE_TEST
> > +     depends on (ARCH_QCOM && QCOM_SCM) || COMPILE_TEST
> >       select USB_ROLE_SWITCH
> >       help
> >         This module enables support for Qualcomm Technologies, Inc.
> > diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c
> > index 74f2aeaccdcb..6face21b7fb7 100644
> > --- a/drivers/usb/misc/qcom_eud.c
> > +++ b/drivers/usb/misc/qcom_eud.c
> > @@ -11,9 +11,11 @@
> >  #include <linux/kernel.h>
> >  #include <linux/module.h>
> >  #include <linux/of.h>
> > +#include <linux/of_device.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/slab.h>
> >  #include <linux/sysfs.h>
> > +#include <linux/firmware/qcom/qcom_scm.h>
> >  #include <linux/usb/role.h>
> >
> >  #define EUD_REG_INT1_EN_MASK 0x0024
> > @@ -30,15 +32,25 @@
> >  #define EUD_INT_SAFE_MODE    BIT(4)
> >  #define EUD_INT_ALL          (EUD_INT_VBUS | EUD_INT_SAFE_MODE)
> >
> > +#define EUD_EN2_EN           BIT(0)
> > +#define EUD_EN2_DISABLE              (0)
> > +#define TCSR_CHECK_EN                BIT(0)
> > +
> > +struct eud_soc_cfg {
> > +     u32 tcsr_check_offset;
> > +};
> > +
> >  struct eud_chip {
> >       struct device                   *dev;
> >       struct usb_role_switch          *role_sw;
> > +     const struct eud_soc_cfg        *eud_cfg;
> >       void __iomem                    *base;
> >       void __iomem                    *mode_mgr;
> >       unsigned int                    int_status;
> >       int                             irq;
> >       bool                            enabled;
> >       bool                            usb_attached;
> > +     phys_addr_t                     secure_mode_mgr;
> >  };
> >
> >  static int enable_eud(struct eud_chip *priv)
> > @@ -46,7 +58,11 @@ static int enable_eud(struct eud_chip *priv)
> >       writel(EUD_ENABLE, priv->base + EUD_REG_CSR_EUD_EN);
> >       writel(EUD_INT_VBUS | EUD_INT_SAFE_MODE,
> >                       priv->base + EUD_REG_INT1_EN_MASK);
> > -     writel(1, priv->mode_mgr + EUD_REG_EUD_EN2);
> > +
> > +     if (priv->secure_mode_mgr)
> > +             qcom_scm_io_writel(priv->secure_mode_mgr + EUD_REG_EUD_EN2, EUD_EN2_EN);
> > +     else
> > +             writel(EUD_EN2_EN, priv->mode_mgr + EUD_REG_EUD_EN2);
> >
> >       return usb_role_switch_set_role(priv->role_sw, USB_ROLE_DEVICE);
> >  }
> > @@ -54,7 +70,11 @@ static int enable_eud(struct eud_chip *priv)
> >  static void disable_eud(struct eud_chip *priv)
> >  {
> >       writel(0, priv->base + EUD_REG_CSR_EUD_EN);
> > -     writel(0, priv->mode_mgr + EUD_REG_EUD_EN2);
> > +
> > +     if (priv->secure_mode_mgr)
> > +             qcom_scm_io_writel(priv->secure_mode_mgr + EUD_REG_EUD_EN2, EUD_EN2_DISABLE);
> > +     else
> > +             writel(EUD_EN2_DISABLE, priv->mode_mgr + EUD_REG_EUD_EN2);
> >  }
> >
> >  static ssize_t enable_show(struct device *dev,
> > @@ -178,6 +198,8 @@ static void eud_role_switch_release(void *data)
> >  static int eud_probe(struct platform_device *pdev)
> >  {
> >       struct eud_chip *chip;
> > +     struct resource *res;
> > +     phys_addr_t tcsr_check;
> >       int ret;
> >
> >       chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
> > @@ -200,9 +222,37 @@ static int eud_probe(struct platform_device *pdev)
> >       if (IS_ERR(chip->base))
> >               return PTR_ERR(chip->base);
> >
> > -     chip->mode_mgr = devm_platform_ioremap_resource(pdev, 1);
> > -     if (IS_ERR(chip->mode_mgr))
> > -             return PTR_ERR(chip->mode_mgr);
> > +     /*
> > +      * EUD block on a few Qualcomm SoCs needs secure register access.
> > +      * Check for the same.
> > +      */
> > +     if (of_device_is_compatible(chip->dev->of_node, "qcom,sm6115-eud")) {
> I didn't notice that this changed between v4 and v5, but in my v4 review
> I suggested using
>
> if (of_property_read_bool(chip->dev->of_node, "qcom,secure-mode-enable"))
>
> as this was the only place where the value of that function was checked
> and caching it in the driver struct simply made no sense (as of today, anyway)
>
> checking the device compatible does not scale very well for something
> generic, as now it'd require adding each qcom,smABCD-eud to this condition
> as well.
>
> > +             res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > +             if (!res)
> > +                     return dev_err_probe(chip->dev, -ENODEV,
> > +                                          "failed to get secure_mode_mgr reg base\n");
> This suggests the reg-name is "secure_mode_mgr" which is not true,
> according to your binding patch. I thought about adding a separate
> entry, but ultimately this would be against the DT philosophy, as it
> references the same physical region as "eud-mode-mgr", just that due
> to ACL software running at a higher exception level it's not
> directly accessible..
>
> I was debating suggesting moving it to SoC configuration, but that
> also depends on the software stack (e.g. there are windows and cros
> 7280 laptops with different security restrictions).. so I think
> the dt property is the way to go.

Well, the changes were done as per Krzysztof's comments on the earlier
versions (see [1] and [2]):

[1]. https://lore.kernel.org/linux-arm-msm/fe326d38-ee52-b0a4-21d8-f00f22449417@linaro.org/
[2]. https://lore.kernel.org/linux-arm-msm/e60af365-4260-a56f-1ec1-c7c60d172b38@linaro.org/

I am fine with either approach. As I originally argued, having a
dt-property seems more useful to me to indicate a secure-mode access.

May be @Krzysztof Kozlowski , can share his opinions on the same.

Thanks,
Bhupesh