diff mbox series

[v7,3/9] usb: dwc3: core: Access XHCI address space temporarily to read port info

Message ID 20230501143445.3851-4-quic_kriskura@quicinc.com
State New
Headers show
Series [v7,1/9] dt-bindings: usb: qcom,dwc3: Add bindings for SC8280 Multiport | expand

Commit Message

Krishna Kurapati May 1, 2023, 2:34 p.m. UTC
Currently host-only capable DWC3 controllers support Multiport.
Temporarily map XHCI address space for host-only controllers and parse
XHCI Extended Capabilities registers to read number of usb2 ports and
usb3 ports present on multiport controller. Each USB Port is at least HS
capable.

The port info for usb2 and usb3 phy are identified as num_usb2_ports
and num_usb3_ports. The intention is as follows:

Wherever we need to perform phy operations like:

LOOP_OVER_NUMBER_OF_AVAILABLE_PORTS()
{
	phy_set_mode(dwc->usb2_generic_phy[i], PHY_MODE_USB_HOST);
	phy_set_mode(dwc->usb3_generic_phy[i], PHY_MODE_USB_HOST);
}

If number of usb2 ports is 3, loop can go from index 0-2 for
usb2_generic_phy. If number of usb3-ports is 2, we don't know for sure,
if the first 2 ports are SS capable or some other ports like (2 and 3)
are SS capable. So instead, num_usb2_ports is used to loop around all
phy's (both hs and ss) for performing phy operations. If any
usb3_generic_phy turns out to be NULL, phy operation just bails out.

num_usb3_ports is used to modify GUSB3PIPECTL registers while setting up
phy's as we need to know how many SS capable ports are there for this.

Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
---
 drivers/usb/dwc3/core.c | 68 +++++++++++++++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.h | 58 +++++++++++++++++++++++++++++++++++
 2 files changed, 126 insertions(+)

Comments

kernel test robot May 2, 2023, 12:27 p.m. UTC | #1
Hi Krishna,

kernel test robot noticed the following build warnings:

[auto build test WARNING on usb/usb-testing]
[also build test WARNING on usb/usb-next usb/usb-linus linus/master next-20230428]
[cannot apply to robh/for-next v6.3]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Krishna-Kurapati/dt-bindings-usb-qcom-dwc3-Add-bindings-for-SC8280-Multiport/20230501-224209
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
patch link:    https://lore.kernel.org/r/20230501143445.3851-4-quic_kriskura%40quicinc.com
patch subject: [PATCH v7 3/9] usb: dwc3: core: Access XHCI address space temporarily to read port info
reproduce:
        # https://github.com/intel-lab-lkp/linux/commit/840e9a485800cf72e5fbf4dca1aaf92085aad584
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Krishna-Kurapati/dt-bindings-usb-qcom-dwc3-Add-bindings-for-SC8280-Multiport/20230501-224209
        git checkout 840e9a485800cf72e5fbf4dca1aaf92085aad584
        make menuconfig
        # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS
        make htmldocs

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202305022053.Tqtl2ROK-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> Documentation/driver-api/usb/dwc3:687: ./drivers/usb/dwc3/core.h:1674: WARNING: Unexpected indentation.
>> Documentation/driver-api/usb/dwc3:687: ./drivers/usb/dwc3/core.h:1675: WARNING: Block quote ends without a blank line; unexpected unindent.
Thinh Nguyen May 2, 2023, 9:41 p.m. UTC | #2
Hi,

On Mon, May 01, 2023, Krishna Kurapati wrote:
> Currently host-only capable DWC3 controllers support Multiport.
> Temporarily map XHCI address space for host-only controllers and parse
> XHCI Extended Capabilities registers to read number of usb2 ports and
> usb3 ports present on multiport controller. Each USB Port is at least HS
> capable.
> 
> The port info for usb2 and usb3 phy are identified as num_usb2_ports
> and num_usb3_ports. The intention is as follows:
> 
> Wherever we need to perform phy operations like:
> 
> LOOP_OVER_NUMBER_OF_AVAILABLE_PORTS()
> {
> 	phy_set_mode(dwc->usb2_generic_phy[i], PHY_MODE_USB_HOST);
> 	phy_set_mode(dwc->usb3_generic_phy[i], PHY_MODE_USB_HOST);
> }
> 
> If number of usb2 ports is 3, loop can go from index 0-2 for
> usb2_generic_phy. If number of usb3-ports is 2, we don't know for sure,
> if the first 2 ports are SS capable or some other ports like (2 and 3)
> are SS capable. So instead, num_usb2_ports is used to loop around all
> phy's (both hs and ss) for performing phy operations. If any
> usb3_generic_phy turns out to be NULL, phy operation just bails out.
> 
> num_usb3_ports is used to modify GUSB3PIPECTL registers while setting up
> phy's as we need to know how many SS capable ports are there for this.
> 
> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
> ---
>  drivers/usb/dwc3/core.c | 68 +++++++++++++++++++++++++++++++++++++++++
>  drivers/usb/dwc3/core.h | 58 +++++++++++++++++++++++++++++++++++
>  2 files changed, 126 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 0beaab932e7d..b8ac7bcee391 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1767,6 +1767,59 @@ static int dwc3_get_clocks(struct dwc3 *dwc)
>  	return 0;
>  }
>  
> +static int dwc3_read_port_info(struct dwc3 *dwc)
> +{
> +	void __iomem		*regs;
> +	u32			offset;
> +	u32			temp;
> +	u8			major_revision;
> +	int			ret = 0;
> +
> +	/*
> +	 * Remap xHCI address space to access XHCI ext cap regs,
> +	 * since it is needed to get port info.
> +	 */
> +	regs = ioremap(dwc->xhci_resources[0].start,
> +				resource_size(&dwc->xhci_resources[0]));
> +	if (IS_ERR(regs))
> +		return PTR_ERR(regs);
> +
> +	offset = dwc3_xhci_find_next_ext_cap(regs, 0,
> +					XHCI_EXT_CAPS_PROTOCOL);
> +	while (offset) {
> +		temp = readl(regs + offset);
> +		major_revision = XHCI_EXT_PORT_MAJOR(temp);
> +
> +		temp = readl(regs + offset + 0x08);
> +		if (major_revision == 0x03) {
> +			dwc->num_usb3_ports += XHCI_EXT_PORT_COUNT(temp);
> +		} else if (major_revision <= 0x02) {
> +			dwc->num_usb2_ports += XHCI_EXT_PORT_COUNT(temp);
> +		} else {
> +			dev_err(dwc->dev, "port revision seems wrong\n");

Can we print this instead:
	dev_err(dwc->dev, "Unrecognized port major revision %d\n", major_revision);

> +			ret = -EINVAL;
> +			goto unmap_reg;
> +		}
> +
> +		offset = dwc3_xhci_find_next_ext_cap(regs, offset,
> +						XHCI_EXT_CAPS_PROTOCOL);
> +	}
> +
> +	temp = readl(regs + DWC3_XHCI_HCSPARAMS1);
> +	if (HCS_MAX_PORTS(temp) != (dwc->num_usb3_ports + dwc->num_usb2_ports)) {
> +		dev_err(dwc->dev, "inconsistency in port info\n");

Can we print this instead:
	dev_err(dwc->dev, "Mismatched reported MAXPORTS (%d)\n", HCS_MAX_PORTS(temp));

> +		ret = -EINVAL;
> +		goto unmap_reg;
> +	}
> +
> +	dev_dbg(dwc->dev,
> +		"hs-ports: %d ss-ports: %d\n", dwc->num_usb2_ports, dwc->num_usb3_ports);
> +
> +unmap_reg:
> +	iounmap(regs);
> +	return ret;
> +}
> +
>  static int dwc3_probe(struct platform_device *pdev)
>  {
>  	struct device		*dev = &pdev->dev;
> @@ -1774,6 +1827,7 @@ static int dwc3_probe(struct platform_device *pdev)
>  	void __iomem		*regs;
>  	struct dwc3		*dwc;
>  	int			ret;
> +	unsigned int		hw_mode;
>  
>  	dwc = devm_kzalloc(dev, sizeof(*dwc), GFP_KERNEL);
>  	if (!dwc)
> @@ -1843,6 +1897,20 @@ static int dwc3_probe(struct platform_device *pdev)
>  			goto err_disable_clks;
>  	}
>  
> +	/*
> +	 * Currently DWC3 controllers that are host-only capable
> +	 * support Multiport
> +	 */
> +	hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
> +	if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST) {
> +		ret = dwc3_read_port_info(dwc);
> +		if (ret)
> +			goto err_disable_clks;
> +	} else {
> +		dwc->num_usb2_ports = 1;
> +		dwc->num_usb3_ports = 1;
> +	}
> +
>  	spin_lock_init(&dwc->lock);
>  	mutex_init(&dwc->mutex);
>  
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index d56457c02996..21312703e053 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -35,6 +35,17 @@
>  
>  #define DWC3_MSG_MAX	500
>  
> +/* Define XHCI Extcap register offsets for getting multiport info */
> +#define XHCI_HCC_PARAMS_OFFSET	0x10
> +#define DWC3_XHCI_HCSPARAMS1	0x04
> +#define XHCI_EXT_CAPS_PROTOCOL	2
> +#define XHCI_HCC_EXT_CAPS(x)    (((x) >> 16) & 0xffff)
> +#define XHCI_EXT_CAPS_ID(x)     (((x) >> 0) & 0xff)
> +#define XHCI_EXT_CAPS_NEXT(x)   (((x) >> 8) & 0xff)
> +#define XHCI_EXT_PORT_MAJOR(x)  (((x) >> 24) & 0xff)
> +#define XHCI_EXT_PORT_COUNT(x)  (((x) >> 8) & 0xff)
> +#define HCS_MAX_PORTS(x)        (((x) >> 24) & 0x7f)
> +
>  /* Global constants */
>  #define DWC3_PULL_UP_TIMEOUT	500	/* ms */
>  #define DWC3_BOUNCE_SIZE	1024	/* size of a superspeed bulk */
> @@ -1025,6 +1036,8 @@ struct dwc3_scratchpad_array {
>   * @usb_psy: pointer to power supply interface.
>   * @usb2_phy: pointer to USB2 PHY
>   * @usb3_phy: pointer to USB3 PHY
> + * @num_usb2_ports: number of usb2 ports.
> + * @num_usb3_ports: number of usb3 ports.
>   * @usb2_generic_phy: pointer to USB2 PHY
>   * @usb3_generic_phy: pointer to USB3 PHY
>   * @phys_ready: flag to indicate that PHYs are ready
> @@ -1162,6 +1175,9 @@ struct dwc3 {
>  	struct usb_phy		*usb2_phy;
>  	struct usb_phy		*usb3_phy;
>  
> +	u32			num_usb2_ports;
> +	u32			num_usb3_ports;

can we use u8?

> +
>  	struct phy		*usb2_generic_phy;
>  	struct phy		*usb3_generic_phy;
>  
> @@ -1650,4 +1666,46 @@ static inline void dwc3_ulpi_exit(struct dwc3 *dwc)
>  { }
>  #endif
>  
> +/**
> + * dwc3_xhci_find_next_ext_cap - Find the offset of the extended capabilities
> + *					with capability ID id.
> + *
> + * @base	PCI MMIO registers base address.
> + * @start	address at which to start looking, (0 or HCC_PARAMS to start at
> + *		beginning of list)
> + * @id		Extended capability ID to search for, or 0 for the next
> + *		capability

I know that this is a duplicate from the xhci driver, but can we fix the
kerneldoc style as in other places if we're going to keep it?

> + *
> + * Returns the offset of the next matching extended capability structure.
> + * Some capabilities can occur several times, e.g., the XHCI_EXT_CAPS_PROTOCOL,
> + * and this provides a way to find them all.
> + */
> +static inline int dwc3_xhci_find_next_ext_cap(void __iomem *base, u32 start, int id)

This is a bit much for an inline function, can we just keep it in core.c
as a static function?

> +{
> +	u32 val;
> +	u32 next;
> +	u32 offset;
> +
> +	offset = start;
> +	if (!start || start == XHCI_HCC_PARAMS_OFFSET) {
> +		val = readl(base + XHCI_HCC_PARAMS_OFFSET);
> +		if (val == ~0)
> +			return 0;
> +		offset = XHCI_HCC_EXT_CAPS(val) << 2;
> +		if (!offset)
> +			return 0;
> +	}
> +	do {
> +		val = readl(base + offset);
> +		if (val == ~0)
> +			return 0;
> +		if (offset != start && (id == 0 || XHCI_EXT_CAPS_ID(val) == id))
> +			return offset;
> +
> +		next = XHCI_EXT_CAPS_NEXT(val);
> +		offset += next << 2;
> +	} while (next);
> +
> +	return 0;
> +}
>  #endif /* __DRIVERS_USB_DWC3_CORE_H */
> -- 
> 2.40.0

Thanks!
Thinh
diff mbox series

Patch

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 0beaab932e7d..b8ac7bcee391 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1767,6 +1767,59 @@  static int dwc3_get_clocks(struct dwc3 *dwc)
 	return 0;
 }
 
+static int dwc3_read_port_info(struct dwc3 *dwc)
+{
+	void __iomem		*regs;
+	u32			offset;
+	u32			temp;
+	u8			major_revision;
+	int			ret = 0;
+
+	/*
+	 * Remap xHCI address space to access XHCI ext cap regs,
+	 * since it is needed to get port info.
+	 */
+	regs = ioremap(dwc->xhci_resources[0].start,
+				resource_size(&dwc->xhci_resources[0]));
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	offset = dwc3_xhci_find_next_ext_cap(regs, 0,
+					XHCI_EXT_CAPS_PROTOCOL);
+	while (offset) {
+		temp = readl(regs + offset);
+		major_revision = XHCI_EXT_PORT_MAJOR(temp);
+
+		temp = readl(regs + offset + 0x08);
+		if (major_revision == 0x03) {
+			dwc->num_usb3_ports += XHCI_EXT_PORT_COUNT(temp);
+		} else if (major_revision <= 0x02) {
+			dwc->num_usb2_ports += XHCI_EXT_PORT_COUNT(temp);
+		} else {
+			dev_err(dwc->dev, "port revision seems wrong\n");
+			ret = -EINVAL;
+			goto unmap_reg;
+		}
+
+		offset = dwc3_xhci_find_next_ext_cap(regs, offset,
+						XHCI_EXT_CAPS_PROTOCOL);
+	}
+
+	temp = readl(regs + DWC3_XHCI_HCSPARAMS1);
+	if (HCS_MAX_PORTS(temp) != (dwc->num_usb3_ports + dwc->num_usb2_ports)) {
+		dev_err(dwc->dev, "inconsistency in port info\n");
+		ret = -EINVAL;
+		goto unmap_reg;
+	}
+
+	dev_dbg(dwc->dev,
+		"hs-ports: %d ss-ports: %d\n", dwc->num_usb2_ports, dwc->num_usb3_ports);
+
+unmap_reg:
+	iounmap(regs);
+	return ret;
+}
+
 static int dwc3_probe(struct platform_device *pdev)
 {
 	struct device		*dev = &pdev->dev;
@@ -1774,6 +1827,7 @@  static int dwc3_probe(struct platform_device *pdev)
 	void __iomem		*regs;
 	struct dwc3		*dwc;
 	int			ret;
+	unsigned int		hw_mode;
 
 	dwc = devm_kzalloc(dev, sizeof(*dwc), GFP_KERNEL);
 	if (!dwc)
@@ -1843,6 +1897,20 @@  static int dwc3_probe(struct platform_device *pdev)
 			goto err_disable_clks;
 	}
 
+	/*
+	 * Currently DWC3 controllers that are host-only capable
+	 * support Multiport
+	 */
+	hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
+	if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST) {
+		ret = dwc3_read_port_info(dwc);
+		if (ret)
+			goto err_disable_clks;
+	} else {
+		dwc->num_usb2_ports = 1;
+		dwc->num_usb3_ports = 1;
+	}
+
 	spin_lock_init(&dwc->lock);
 	mutex_init(&dwc->mutex);
 
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index d56457c02996..21312703e053 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -35,6 +35,17 @@ 
 
 #define DWC3_MSG_MAX	500
 
+/* Define XHCI Extcap register offsets for getting multiport info */
+#define XHCI_HCC_PARAMS_OFFSET	0x10
+#define DWC3_XHCI_HCSPARAMS1	0x04
+#define XHCI_EXT_CAPS_PROTOCOL	2
+#define XHCI_HCC_EXT_CAPS(x)    (((x) >> 16) & 0xffff)
+#define XHCI_EXT_CAPS_ID(x)     (((x) >> 0) & 0xff)
+#define XHCI_EXT_CAPS_NEXT(x)   (((x) >> 8) & 0xff)
+#define XHCI_EXT_PORT_MAJOR(x)  (((x) >> 24) & 0xff)
+#define XHCI_EXT_PORT_COUNT(x)  (((x) >> 8) & 0xff)
+#define HCS_MAX_PORTS(x)        (((x) >> 24) & 0x7f)
+
 /* Global constants */
 #define DWC3_PULL_UP_TIMEOUT	500	/* ms */
 #define DWC3_BOUNCE_SIZE	1024	/* size of a superspeed bulk */
@@ -1025,6 +1036,8 @@  struct dwc3_scratchpad_array {
  * @usb_psy: pointer to power supply interface.
  * @usb2_phy: pointer to USB2 PHY
  * @usb3_phy: pointer to USB3 PHY
+ * @num_usb2_ports: number of usb2 ports.
+ * @num_usb3_ports: number of usb3 ports.
  * @usb2_generic_phy: pointer to USB2 PHY
  * @usb3_generic_phy: pointer to USB3 PHY
  * @phys_ready: flag to indicate that PHYs are ready
@@ -1162,6 +1175,9 @@  struct dwc3 {
 	struct usb_phy		*usb2_phy;
 	struct usb_phy		*usb3_phy;
 
+	u32			num_usb2_ports;
+	u32			num_usb3_ports;
+
 	struct phy		*usb2_generic_phy;
 	struct phy		*usb3_generic_phy;
 
@@ -1650,4 +1666,46 @@  static inline void dwc3_ulpi_exit(struct dwc3 *dwc)
 { }
 #endif
 
+/**
+ * dwc3_xhci_find_next_ext_cap - Find the offset of the extended capabilities
+ *					with capability ID id.
+ *
+ * @base	PCI MMIO registers base address.
+ * @start	address at which to start looking, (0 or HCC_PARAMS to start at
+ *		beginning of list)
+ * @id		Extended capability ID to search for, or 0 for the next
+ *		capability
+ *
+ * Returns the offset of the next matching extended capability structure.
+ * Some capabilities can occur several times, e.g., the XHCI_EXT_CAPS_PROTOCOL,
+ * and this provides a way to find them all.
+ */
+static inline int dwc3_xhci_find_next_ext_cap(void __iomem *base, u32 start, int id)
+{
+	u32 val;
+	u32 next;
+	u32 offset;
+
+	offset = start;
+	if (!start || start == XHCI_HCC_PARAMS_OFFSET) {
+		val = readl(base + XHCI_HCC_PARAMS_OFFSET);
+		if (val == ~0)
+			return 0;
+		offset = XHCI_HCC_EXT_CAPS(val) << 2;
+		if (!offset)
+			return 0;
+	}
+	do {
+		val = readl(base + offset);
+		if (val == ~0)
+			return 0;
+		if (offset != start && (id == 0 || XHCI_EXT_CAPS_ID(val) == id))
+			return offset;
+
+		next = XHCI_EXT_CAPS_NEXT(val);
+		offset += next << 2;
+	} while (next);
+
+	return 0;
+}
 #endif /* __DRIVERS_USB_DWC3_CORE_H */