add support for DWC UFS Controller

Signed-off-by Joao Pinto <[email protected]>

drivers/scsi/ufs/Kconfig +16 -0

+config SCSI_UFS_DWC_MPHY_TC
+	bool "Support for the Synopsys MPHY Test Chip"
+	depends on SCSI_UFS_DWC_HOOKS && (SCSI_UFSHCD_PCI || SCSI_UFS_DWC_PLAT)
+	---help---
+	  This selects the support for the Synopsys MPHY Test Chip.
+
+	  Select this if you have a Synopsys MPHY Test Chip.
+	  If unsure, say N.
+
+config SCSI_UFS_DWC_20BIT_RMMI
+	bool "20-bit RMMI MPHY"
+	depends on SCSI_UFS_DWC_MPHY_TC
+	---help---
+	  This specifies that the Synopsys MPHY supports 40-bit RMMI operations.
+
+	  Select this if you are using a 40-bit RMMI Synopsys MPHY.

drivers/scsi/ufs/ufshcd-dwc.c new file +30 -0

+/**
+ * ufshcd_dwc_setup_mphy()
+ * This function configures Local (host) Synopsys MPHY specific attributes
+ *
+ * @hba: Pointer to drivers structure
+ *
+ * Returns 0 on success non-zero value on failure
+ */
+int ufshcd_dwc_setup_mphy(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+#ifdef CONFIG_SCSI_UFS_DWC_40BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 40-bit RMMI");
+	ret = ufshcd_dwc_setup_40bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "40-bit RMMI configuration failed");
+		goto out;
+	}
+#else
+#ifdef CONFIG_SCSI_UFS_DWC_20BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 20-bit RMMI");
+	ret = ufshcd_dwc_setup_20bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "20-bit RMMI configuration failed");
+		goto out;
+	}
+#endif
+#endif
+	/* To write Shadow register bank to effective configuration block */

drivers/scsi/ufs/ufshcd-pci.c +16 -0

index d15eaa4..66518a1 100644
@@ -34,6 +34,9 @@
  */
 
 #include "ufshcd.h"
+#ifdef CONFIG_SCSI_UFS_DWC_HOOKS
+#include "ufshcd-dwc.h"
+#endif
 #include <linux/pci.h>
 #include <linux/pm_runtime.h>
 

@@ -83,6 +86,16 @@ static int ufshcd_pci_runtime_idle(struct device *dev)
 #define ufshcd_pci_runtime_idle	NULL
 #endif /* CONFIG_PM */
 
+#ifdef CONFIG_SCSI_UFS_DWC_HOOKS
+/**
+ * struct ufs_hba_dwc_vops - UFS DWC specific variant operations
+ */
+static struct ufs_hba_variant_ops ufs_dwc_pci_hba_vops = {
+	.name                   = "dwc-pci",
+	.custom_probe_hba	= ufshcd_dwc_configuration,
+};
+#endif
+
 /**
  * ufshcd_pci_shutdown - main function to put the controller in reset state
  * @pdev: pointer to PCI device handle

@@ -144,6 +157,9 @@ ufshcd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	INIT_LIST_HEAD(&hba->clk_list_head);
 
+#ifdef CONFIG_SCSI_UFS_DWC_HOOKS
+	hba->vops = &ufs_dwc_pci_hba_vops;
+#endif
 	err = ufshcd_init(hba, mmio_base, pdev->irq);
 	if (err) {
 		dev_err(&pdev->dev, "Initialization failed\n");

Quoted 2 lines · On Wednesday 03 February 2016 11:28:26 Joao Pinto wrote:

Signed-off-by Joao Pinto <jpinto-HKixBCOQz3hWk0Htik3J/[email protected]>

This needs a changelog comment, like every patch.

Documentation/devicetree/bindings/ufs/ufs-dwc.txt line 7

Quoted 8 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt new file +7 -0

@@ -0,0 +1,16 @@
+* Universal Flash Storage (UFS) DesignWare Host Controller
+
+DWC_UFSHC nodes are defined to describe on-chip UFS host controllers.
+Each UFS controller instance should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "snps,ufshcd"

Are there multiple versions of this controller? Usually for designware parts the version is known, so we should document which versions exist

drivers/scsi/ufs/Kconfig config SCSI_UFS_QCOM · line 94

Quoted 10 lines

drivers/scsi/ufs/Kconfig +9 -0

+
+config SCSI_UFS_DWC_HOOKS
+	bool "DesignWare hooks to UFS controller"
+	depends on SCSI_UFSHCD
+	---help---
+	  This selects the DesignWare hooks for the UFS host controller.
+
+	  Select this if you have a DesignWare UFS controller.
+	  If unsure, say N.

This could be a silent symbol that gets selected by SCSI_UFS_DWC_PLAT

Quoted 23 lines

drivers/scsi/ufs/Kconfig +22 -0

+config SCSI_UFS_DWC_MPHY_TC
+	bool "Support for the Synopsys MPHY Test Chip"
+	depends on SCSI_UFS_DWC_HOOKS && (SCSI_UFSHCD_PCI || SCSI_UFS_DWC_PLAT)
+	---help---
+	  This selects the support for the Synopsys MPHY Test Chip.
+
+	  Select this if you have a Synopsys MPHY Test Chip.
+	  If unsure, say N.
+
+config SCSI_UFS_DWC_20BIT_RMMI
+	bool "20-bit RMMI MPHY"
+	depends on SCSI_UFS_DWC_MPHY_TC
+	---help---
+	  This specifies that the Synopsys MPHY supports 40-bit RMMI operations.
+
+	  Select this if you are using a 40-bit RMMI Synopsys MPHY.
+	  If unsure, say N.
+
+config SCSI_UFS_DWC_40BIT_RMMI
+	bool "40-bit RMMI MPHY"
+	depends on SCSI_UFS_DWC_MPHY_TC
+	---help---

drivers/scsi/ufs/Kconfig config SCSI_UFS_QCOM · line 121

Quoted 4 lines

drivers/scsi/ufs/Kconfig +4 -0

+	  This specifies that the Synopsys MPHY supports 40-bit RMMI operations.
+
+	  Select this if you are using a 40-bit RMMI Synopsys MPHY.
+	  If unsure, say N.

Move the PHY config options to drivers/phy/ along with the respective drivers, the device using the PHY should not need to be aware which one is being used.

Quoted 35 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +34 -0

+/**
+ * ufshcd_dwc_setup_mphy()
+ * This function configures Local (host) Synopsys MPHY specific attributes
+ *
+ * @hba: Pointer to drivers structure
+ *
+ * Returns 0 on success non-zero value on failure
+ */
+int ufshcd_dwc_setup_mphy(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+#ifdef CONFIG_SCSI_UFS_DWC_40BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 40-bit RMMI");
+	ret = ufshcd_dwc_setup_40bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "40-bit RMMI configuration failed");
+		goto out;
+	}
+#else
+#ifdef CONFIG_SCSI_UFS_DWC_20BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 20-bit RMMI");
+	ret = ufshcd_dwc_setup_20bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "20-bit RMMI configuration failed");
+		goto out;
+	}
+#endif
+#endif
+	/* To write Shadow register bank to effective configuration block */
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_MPHYCFGUPDT), 0x01);
+	if (ret)
+		goto out;
+

drivers/scsi/ufs/ufshcd-dwc.c line 696

Quoted 6 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +6 -0

+	/* To configure Debug OMC */
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_DEBUGOMC), 0x01);
+
+out:
+	return ret;
+}

Try to use the generic PHY abstraction here and remove all the #ifdef etc.

Quoted 44 lines

drivers/scsi/ufs/ufshcd-pci.c +16 -0

index d15eaa4..66518a1 100644
@@ -34,6 +34,9 @@
  */
 
 #include "ufshcd.h"
+#ifdef CONFIG_SCSI_UFS_DWC_HOOKS
+#include "ufshcd-dwc.h"
+#endif
 #include <linux/pci.h>
 #include <linux/pm_runtime.h>
 

@@ -83,6 +86,16 @@ static int ufshcd_pci_runtime_idle(struct device *dev)
 #define ufshcd_pci_runtime_idle	NULL
 #endif /* CONFIG_PM */
 
+#ifdef CONFIG_SCSI_UFS_DWC_HOOKS
+/**
+ * struct ufs_hba_dwc_vops - UFS DWC specific variant operations
+ */
+static struct ufs_hba_variant_ops ufs_dwc_pci_hba_vops = {
+	.name                   = "dwc-pci",
+	.custom_probe_hba	= ufshcd_dwc_configuration,
+};
+#endif
+
 /**
  * ufshcd_pci_shutdown - main function to put the controller in reset state
  * @pdev: pointer to PCI device handle

@@ -144,6 +157,9 @@ ufshcd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	INIT_LIST_HEAD(&hba->clk_list_head);
 
+#ifdef CONFIG_SCSI_UFS_DWC_HOOKS
+	hba->vops = &ufs_dwc_pci_hba_vops;
+#endif
 	err = ufshcd_init(hba, mmio_base, pdev->irq);
 	if (err) {
 		dev_err(&pdev->dev, "Initialization failed\n");

@@ -167,6 +183,10 @@ static const struct dev_pm_ops ufshcd_pci_pm_ops = {
 

drivers/scsi/ufs/ufshcd-pci.c static const struct dev_pm_ops ufshcd_pci_pm_ops = { · line 191

Quoted 8 lines

drivers/scsi/ufs/ufshcd-pci.c +4 -0

 static const struct pci_device_id ufshcd_pci_tbl[] = {
 	{ PCI_VENDOR_ID_SAMSUNG, 0xC00C, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
+#ifdef CONFIG_SCSI_UFS_DWC_HOOKS
+	{ PCI_VENDOR_ID_SYNOPSYS, 0xB101, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
+	{ PCI_VENDOR_ID_SYNOPSYS, 0xB102, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
+#endif
 	{ }	/* terminate list */
 };

I think you're better off with a separate PCI driver for this. Remove all the #ifdef mess here, put whatever is dwc specific into a new file, and perhaps move the common parts into a shared file that can be used by both the samsung and designware drivers.

Arnd

Hi Arnd,

Quoted 6 lines · Arnd Bergmann

Quoted 2 lines · On Wednesday 03 February 2016 11:28:26 Joao Pinto wrote:

Signed-off-by Joao Pinto <[email protected]>

This needs a changelog comment, like every patch.

Quoted 11 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt line 7

Quoted 8 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt new file +7 -0

@@ -0,0 +1,16 @@
+* Universal Flash Storage (UFS) DesignWare Host Controller
+
+DWC_UFSHC nodes are defined to describe on-chip UFS host controllers.
+Each UFS controller instance should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "snps,ufshcd"

Are there multiple versions of this controller? Usually for designware parts the version is known, so we should document which versions exist

This controller recent releases was 2.0, but we released last year 1.1. The driver works with both. The driver must work with all DWC UFS versions.

Quoted 10 lines

drivers/scsi/ufs/Kconfig config SCSI_UFS_QCOM · line 94

Quoted 8 lines

drivers/scsi/ufs/Kconfig +8 -0

+config SCSI_UFS_DWC_HOOKS
+	bool "DesignWare hooks to UFS controller"
+	depends on SCSI_UFSHCD
+	---help---
+	  This selects the DesignWare hooks for the UFS host controller.
+
+	  Select this if you have a DesignWare UFS controller.
+	  If unsure, say N.

This could be a silent symbol that gets selected by SCSI_UFS_DWC_PLAT

We could do that, but imagine that we select SCSI_UFS_QCOM, then the synopsys hooks would be selected also which in my opinion is not very accurate. In my opinion we should have a selectable DWC_HOOKS.

Quoted 34 lines

Quoted 34 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +34 -0

+/**
+ * ufshcd_dwc_setup_mphy()
+ * This function configures Local (host) Synopsys MPHY specific attributes
+ *
+ * @hba: Pointer to drivers structure
+ *
+ * Returns 0 on success non-zero value on failure
+ */
+int ufshcd_dwc_setup_mphy(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+#ifdef CONFIG_SCSI_UFS_DWC_40BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 40-bit RMMI");
+	ret = ufshcd_dwc_setup_40bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "40-bit RMMI configuration failed");
+		goto out;
+	}
+#else
+#ifdef CONFIG_SCSI_UFS_DWC_20BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 20-bit RMMI");
+	ret = ufshcd_dwc_setup_20bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "20-bit RMMI configuration failed");
+		goto out;
+	}
+#endif
+#endif
+	/* To write Shadow register bank to effective configuration block */
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_MPHYCFGUPDT), 0x01);
+	if (ret)
+		goto out;
+

Quoted 8 lines

drivers/scsi/ufs/ufshcd-dwc.c line 696

Quoted 6 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +6 -0

+	/* To configure Debug OMC */
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_DEBUGOMC), 0x01);
+
+out:
+	return ret;
+}

Try to use the generic PHY abstraction here and remove all the #ifdef etc.

Could you please point an example for me to check?

Quoted 6 lines

Quoted 1 line

};

I think you're better off with a separate PCI driver for this. Remove all the #ifdef mess here, put whatever is dwc specific into a new file, and perhaps move the common parts into a shared file that can be used by both the samsung and designware drivers.

I have a branch with that approach, but honestly it would be a big change in the UFS arch for the pci and I decided to make it simple. I sent that suggestion for the scsi mailing list and the comments showed me that. Does anyone have anything against putting ufshcd-pci.c as a pci common code and then have a ufs-dwc-pci.c and a ufs-samsung-pci.c that uses that common code?

Quoted 22 lines · On Wednesday 03 February 2016 15:01:34 Joao Pinto wrote:

Hi Arnd,

Quoted 6 lines · Arnd Bergmann

Quoted 2 lines · On Wednesday 03 February 2016 11:28:26 Joao Pinto wrote:

Signed-off-by Joao Pinto <[email protected]>

This needs a changelog comment, like every patch.

Quoted 11 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt line 7

Quoted 8 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt new file +7 -0

@@ -0,0 +1,16 @@
+* Universal Flash Storage (UFS) DesignWare Host Controller
+
+DWC_UFSHC nodes are defined to describe on-chip UFS host controllers.
+Each UFS controller instance should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "snps,ufshcd"

Are there multiple versions of this controller? Usually for designware parts the version is known, so we should document which versions exist

Quoted 2 lines

This controller recent releases was 2.0, but we released last year 1.1. The driver works with both. The driver must work with all DWC UFS versions.

Ok, then make the driver match on the "snps,ufshcd-1.1" compatible string, but document both strings in the binding document, and make it mandatory to specify the 1.1 version as a compatible fallback.

If we ever need to handle a quirk for the 2.0 version then, it can easily be done.

Quoted 12 lines

Quoted 11 lines

drivers/scsi/ufs/Kconfig config SCSI_UFS_QCOM · line 94

Quoted 9 lines

drivers/scsi/ufs/Kconfig +8 -0

+config SCSI_UFS_DWC_HOOKS
+	bool "DesignWare hooks to UFS controller"
+	depends on SCSI_UFSHCD
+	---help---
+	  This selects the DesignWare hooks for the UFS host controller.
+
+	  Select this if you have a DesignWare UFS controller.
+	  If unsure, say N.

This could be a silent symbol that gets selected by SCSI_UFS_DWC_PLAT

Quoted 3 lines

We could do that, but imagine that we select SCSI_UFS_QCOM, then the synopsys hooks would be selected also which in my opinion is not very accurate. In my opinion we should have a selectable DWC_HOOKS.

I don't understand. At the moment, you can enable SCSI_UFS_DWC_HOOKS even if nothing uses it and you only have SCSI_UFS_QCOM enabled.

With my suggestion, the hooks would disappear unless they are actually used.

Then again, with my later comments, we no longer need the hooks.

Quoted 43 lines

Quoted 42 lines

Quoted 30 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +30 -0

+/**
+ * ufshcd_dwc_setup_mphy()
+ * This function configures Local (host) Synopsys MPHY specific attributes
+ *
+ * @hba: Pointer to drivers structure
+ *
+ * Returns 0 on success non-zero value on failure
+ */
+int ufshcd_dwc_setup_mphy(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+#ifdef CONFIG_SCSI_UFS_DWC_40BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 40-bit RMMI");
+	ret = ufshcd_dwc_setup_40bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "40-bit RMMI configuration failed");
+		goto out;
+	}
+#else
+#ifdef CONFIG_SCSI_UFS_DWC_20BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 20-bit RMMI");
+	ret = ufshcd_dwc_setup_20bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "20-bit RMMI configuration failed");
+		goto out;
+	}
+#endif
+#endif
+	/* To write Shadow register bank to effective configuration block */

drivers/scsi/ufs/ufshcd-dwc.c line 696

Quoted 10 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +10 -0

+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_MPHYCFGUPDT), 0x01);
+	if (ret)
+		goto out;
+
+	/* To configure Debug OMC */
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_DEBUGOMC), 0x01);
+
+out:
+	return ret;
+}

Try to use the generic PHY abstraction here and remove all the #ifdef etc.

Quoted 1 line

Could you please point an example for me to check?

drivers/phy/phy-qcom-ufs-qmp-14nm.c is a phy driver, and it gets used through the generic devm_phy_get()/phy_power_on()/phy_power_off()/... interfaces.

This should probably be moved into the generic UFS platform driver so the PHY handling can be shared between all backends.

Quoted 7 lines

Quoted 6 lines

Quoted 1 line

};

I think you're better off with a separate PCI driver for this. Remove all the #ifdef mess here, put whatever is dwc specific into a new file, and perhaps move the common parts into a shared file that can be used by both the samsung and designware drivers.

Quoted 5 lines

I have a branch with that approach, but honestly it would be a big change in the UFS arch for the pci and I decided to make it simple. I sent that suggestion for the scsi mailing list and the comments showed me that. Does anyone have anything against putting ufshcd-pci.c as a pci common code and then have a ufs-dwc-pci.c and a ufs-samsung-pci.c that uses that common code?

Another approach would be to just rename the existing file to ufs-samsung-pci.c and start the ufs-dwc-pci.c as a copy of that. The file is not really all that large anyway.

Arnd

Hi,

Quoted 30 lines · Arnd Bergmann

Quoted 22 lines · On Wednesday 03 February 2016 15:01:34 Joao Pinto wrote:

Hi Arnd,

Quoted 6 lines · Arnd Bergmann

Quoted 2 lines · On Wednesday 03 February 2016 11:28:26 Joao Pinto wrote:

Signed-off-by Joao Pinto <jpinto-HKixBCOQz3hWk0Htik3J/[email protected]>

This needs a changelog comment, like every patch.

Quoted 11 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt line 7

Quoted 8 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt new file +7 -0

@@ -0,0 +1,16 @@
+* Universal Flash Storage (UFS) DesignWare Host Controller
+
+DWC_UFSHC nodes are defined to describe on-chip UFS host controllers.
+Each UFS controller instance should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "snps,ufshcd"

Are there multiple versions of this controller? Usually for designware parts the version is known, so we should document which versions exist

Quoted 2 lines

This controller recent releases was 2.0, but we released last year 1.1. The driver works with both. The driver must work with all DWC UFS versions.

Ok, then make the driver match on the "snps,ufshcd-1.1" compatible string, but document both strings in the binding document, and make it mandatory to specify the 1.1 version as a compatible fallback.

Quoted 2 lines

If we ever need to handle a quirk for the 2.0 version then, it can easily be done.

We need the driver to support UFS 2.0 because it is our latest release and is the done that Synopsys is focused now. We could call it "snps, ufshcd-2.0" then. What do you think?

Quoted 33 lines · Joao Pinto

Hi,

Quoted 30 lines · Arnd Bergmann

Quoted 22 lines · On Wednesday 03 February 2016 15:01:34 Joao Pinto wrote:

Hi Arnd,

Quoted 6 lines · Arnd Bergmann

Quoted 2 lines · On Wednesday 03 February 2016 11:28:26 Joao Pinto wrote:

Signed-off-by Joao Pinto <jpinto-HKixBCOQz3hWk0Htik3J/[email protected]>

This needs a changelog comment, like every patch.

Quoted 11 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt line 7

Quoted 8 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt new file +7 -0

@@ -0,0 +1,16 @@
+* Universal Flash Storage (UFS) DesignWare Host Controller
+
+DWC_UFSHC nodes are defined to describe on-chip UFS host controllers.
+Each UFS controller instance should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "snps,ufshcd"

Are there multiple versions of this controller? Usually for designware parts the version is known, so we should document which versions exist

Quoted 2 lines

This controller recent releases was 2.0, but we released last year 1.1. The driver works with both. The driver must work with all DWC UFS versions.

Ok, then make the driver match on the "snps,ufshcd-1.1" compatible string, but document both strings in the binding document, and make it mandatory to specify the 1.1 version as a compatible fallback.

Quoted 6 lines

Quoted 2 lines

If we ever need to handle a quirk for the 2.0 version then, it can easily be done.

We need the driver to support UFS 2.0 because it is our latest release and is the done that Synopsys is focused now. We could call it "snps, ufshcd-2.0" then. What do you think?

Arnd's point was that the driver can handle only "snps,ufshcd-1.1" for now, and in your DT you can have:

	compatible = "snps,ufshcd-2.0", "snps,ufshcd-1.1";

That allows driver to handle 2.0 and 1.1 without knowing anything about 2.0 for now. If in future the two need to be handled differently we can update the driver to explicitly match "snps,ufshcd-2.0".

Regardless, both compatible string should go in the documentation, and it should be explicitly mentioned that "snps,ufshcd-1.1" should be used as a fallback entry.

Mark.

Hi Mark and Arnd,

I am planning the v2 of this patch set. I have a doubt in the version compatibility strings... The core driver must support the UFS 2.0 controller and this patch set includes a patch that adds 2.0 capabilities to it.

The core driver can get from the controller's version and with that use or not a specific 2.0 feature.

What would be the real added-value of having a compatibility string like "snps,ufshcd-1.1" and "snps,ufshcd-2.0" if the driver can perform as 2.0 if it detects a 2.0 controller?

Are you saying that a user that puts "snps,ufshcd-1.1"
in the DT compatibility string disables the UFS 2.0 in the core driver despite the controller is 2.0? Please clarify.

Quoted 5 lines · Joao Pinto

Hi Mark and Arnd,

I am planning the v2 of this patch set. I have a doubt in the version compatibility strings... The core driver must support the UFS 2.0 controller and this patch set includes a patch that adds 2.0 capabilities to it.

Ok. It wasn't clear to me that this series added support for features specific to 2.0.

Quoted 3 lines

The core driver can get from the controller's version and with that use or not a specific 2.0 feature.

It can be detected from the hardware?

Quoted 4 lines

What would be the real added-value of having a compatibility string like "snps,ufshcd-1.1" and "snps,ufshcd-2.0" if the driver can perform as 2.0 if it detects a 2.0 controller?

Generally having specify strings ensure that it's possible to handle things in future (e.g. errata workarounds), or if we realise something isn't as clear-cut as we thought it was (i.e. 2.0 not being a strict superset of 1.1).

It's difficult to predict when you need that, so we err on the side of requiring it. At worst it means you have a small redundant few characters in a DT, but that's a much better proposition than having too little information.

Quoted 3 lines

Are you saying that a user that puts "snps,ufshcd-1.1"
in the DT compatibility string disables the UFS 2.0 in the core driver despite the controller is 2.0? Please clarify.

If you can consistently and safely detect that the HW is 2.0, using 2.0 functionality is fine.

Regardless, you should have a -1.1 compatible string for the 1.1 HW, and a -2.0 string for the 2.0 HW, so that DTs are explicit about what the hardware is. If 2.0 is intended to be a superset of 1.1, you can have a 1.1 fallback entry for the 2.0 hardware.

Thanks,
Mark.

Hi Mark,

Quoted 6 lines · Mark Rutland

Quoted 4 lines · Joao Pinto

Hi Mark and Arnd,
Are you saying that a user that puts "snps,ufshcd-1.1"
in the DT compatibility string disables the UFS 2.0 in the core driver despite the controller is 2.0? Please clarify.

Quoted 8 lines

If you can consistently and safely detect that the HW is 2.0, using 2.0 functionality is fine.

Regardless, you should have a -1.1 compatible string for the 1.1 HW, and a -2.0 string for the 2.0 HW, so that DTs are explicit about what the hardware is. If 2.0 is intended to be a superset of 1.1, you can have a 1.1 fallback entry for the 2.0 hardware.

Ok, I will include the version in the compatibility strings, but if someone mentions "snps,ufshcd-1.1" only and the driver detects that the HW is 2.0 capable it will activate the 2.0 features independently of what mentioned in the DT, correct?

Quoted 18 lines · Joao Pinto

Hi Mark,

Quoted 14 lines · Mark Rutland

Quoted 4 lines · Joao Pinto

Hi Mark and Arnd,
Are you saying that a user that puts "snps,ufshcd-1.1"
in the DT compatibility string disables the UFS 2.0 in the core driver despite the controller is 2.0? Please clarify.

If you can consistently and safely detect that the HW is 2.0, using 2.0 functionality is fine.

Regardless, you should have a -1.1 compatible string for the 1.1 HW, and a -2.0 string for the 2.0 HW, so that DTs are explicit about what the hardware is. If 2.0 is intended to be a superset of 1.1, you can have a 1.1 fallback entry for the 2.0 hardware.

Quoted 4 lines

Ok, I will include the version in the compatibility strings, but if someone mentions "snps,ufshcd-1.1" only and the driver detects that the HW is 2.0 capable it will activate the 2.0 features independently of what mentioned in the DT, correct?

As above, if that can be detected safely and reliably, then I don't see a problem with that.

Thanks,
Mark.

Quoted 22 lines · On Wednesday 03 February 2016 15:01:34 Joao Pinto wrote:

Hi Arnd,

Quoted 6 lines · Arnd Bergmann

Quoted 2 lines · On Wednesday 03 February 2016 11:28:26 Joao Pinto wrote:

Signed-off-by Joao Pinto <[email protected]>

This needs a changelog comment, like every patch.

Quoted 11 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt line 7

Quoted 8 lines

Documentation/devicetree/bindings/ufs/ufs-dwc.txt new file +7 -0

@@ -0,0 +1,16 @@
+* Universal Flash Storage (UFS) DesignWare Host Controller
+
+DWC_UFSHC nodes are defined to describe on-chip UFS host controllers.
+Each UFS controller instance should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "snps,ufshcd"

Are there multiple versions of this controller? Usually for designware parts the version is known, so we should document which versions exist

Quoted 2 lines

This controller recent releases was 2.0, but we released last year 1.1. The driver works with both. The driver must work with all DWC UFS versions.

Ok, then make the driver match on the "snps,ufshcd-1.1" compatible string, but document both strings in the binding document, and make it mandatory to specify the 1.1 version as a compatible fallback.

If we ever need to handle a quirk for the 2.0 version then, it can easily be done.

Quoted 11 lines

Quoted 10 lines

drivers/scsi/ufs/Kconfig config SCSI_UFS_QCOM · line 94

Quoted 8 lines

drivers/scsi/ufs/Kconfig +8 -0

+config SCSI_UFS_DWC_HOOKS
+	bool "DesignWare hooks to UFS controller"
+	depends on SCSI_UFSHCD
+	---help---
+	  This selects the DesignWare hooks for the UFS host controller.
+
+	  Select this if you have a DesignWare UFS controller.
+	  If unsure, say N.

This could be a silent symbol that gets selected by SCSI_UFS_DWC_PLAT

Quoted 3 lines

We could do that, but imagine that we select SCSI_UFS_QCOM, then the synopsys hooks would be selected also which in my opinion is not very accurate. In my opinion we should have a selectable DWC_HOOKS.

I don't understand. At the moment, you can enable SCSI_UFS_DWC_HOOKS even if nothing uses it and you only have SCSI_UFS_QCOM enabled.

With my suggestion, the hooks would disappear unless they are actually used.

Then again, with my later comments, we no longer need the hooks.

Quoted 43 lines

Quoted 34 lines

Quoted 34 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +34 -0

+/**
+ * ufshcd_dwc_setup_mphy()
+ * This function configures Local (host) Synopsys MPHY specific attributes
+ *
+ * @hba: Pointer to drivers structure
+ *
+ * Returns 0 on success non-zero value on failure
+ */
+int ufshcd_dwc_setup_mphy(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+#ifdef CONFIG_SCSI_UFS_DWC_40BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 40-bit RMMI");
+	ret = ufshcd_dwc_setup_40bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "40-bit RMMI configuration failed");
+		goto out;
+	}
+#else
+#ifdef CONFIG_SCSI_UFS_DWC_20BIT_RMMI
+	dev_info(hba->dev, "Configuring MPHY 20-bit RMMI");
+	ret = ufshcd_dwc_setup_20bit_rmmi(hba);
+	if (ret) {
+		dev_err(hba->dev, "20-bit RMMI configuration failed");
+		goto out;
+	}
+#endif
+#endif
+	/* To write Shadow register bank to effective configuration block */
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_MPHYCFGUPDT), 0x01);
+	if (ret)
+		goto out;
+

Quoted 8 lines

drivers/scsi/ufs/ufshcd-dwc.c line 696

Quoted 6 lines

drivers/scsi/ufs/ufshcd-dwc.c new file +6 -0

+	/* To configure Debug OMC */
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_DEBUGOMC), 0x01);
+
+out:
+	return ret;
+}

Try to use the generic PHY abstraction here and remove all the #ifdef etc.

Quoted 1 line

Could you please point an example for me to check?

drivers/phy/phy-qcom-ufs-qmp-14nm.c is a phy driver, and it gets used through the generic devm_phy_get()/phy_power_on()/phy_power_off()/... interfaces.

This should probably be moved into the generic UFS platform driver so the PHY handling can be shared between all backends.

Quoted 7 lines

Quoted 6 lines

Quoted 1 line

};

I think you're better off with a separate PCI driver for this. Remove all the #ifdef mess here, put whatever is dwc specific into a new file, and perhaps move the common parts into a shared file that can be used by both the samsung and designware drivers.

Quoted 5 lines

I have a branch with that approach, but honestly it would be a big change in the UFS arch for the pci and I decided to make it simple. I sent that suggestion for the scsi mailing list and the comments showed me that. Does anyone have anything against putting ufshcd-pci.c as a pci common code and then have a ufs-dwc-pci.c and a ufs-samsung-pci.c that uses that common code?

Another approach would be to just rename the existing file to ufs-samsung-pci.c and start the ufs-dwc-pci.c as a copy of that. The file is not really all that large anyway.

Arnd