From c5c72d252dc8e417388386d5767ea790ee8f5b44 Mon Sep 17 00:00:00 2001 From: Adam Wallis Date: Fri, 8 Dec 2017 17:59:13 +0200 Subject: [PATCH 191/224] usb: xhci: allow imod-interval to be configurable The xHCI driver currently has the IMOD set to 160, which translates to an IMOD interval of 40,000ns (160 * 250)ns Commit 0cbd4b34cda9 ("xhci: mediatek: support MTK xHCI host controller") introduced a QUIRK for the MTK platform to adjust this interval to 20, which translates to an IMOD interval of 5,000ns (20 * 250)ns. This is due to the fact that the MTK controller IMOD interval is 8 times as much as defined in xHCI spec. Instead of adding more quirk bits for additional platforms, this patch introduces the ability for vendors to set the IMOD_INTERVAL as is optimal for their platform. By using device_property_read_u32() on "imod-interval-ns", the IMOD INTERVAL can be specified in nano seconds. If no interval is specified, the default of 40,000ns (IMOD=160) will be used. No bounds checking has been implemented due to the fact that a vendor may have violated the spec and would need to specify a value outside of the max 8,000 IRQs/second limit specified in the xHCI spec. Tested-by: Chunfeng Yun Reviewed-by: Rob Herring Signed-off-by: Adam Wallis Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.txt | 2 ++ Documentation/devicetree/bindings/usb/usb-xhci.txt | 1 + drivers/usb/host/xhci-mtk.c | 9 +++++++++ drivers/usb/host/xhci-pci.c | 3 +++ drivers/usb/host/xhci-plat.c | 5 +++++ drivers/usb/host/xhci.c | 6 +----- drivers/usb/host/xhci.h | 2 ++ 7 files changed, 23 insertions(+), 5 deletions(-) --- a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.txt +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.txt @@ -46,6 +46,7 @@ Optional properties: - pinctrl-names : a pinctrl state named "default" must be defined - pinctrl-0 : pin control group See: Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt + - imod-interval-ns: default interrupt moderation interval is 5000ns Example: usb30: usb@11270000 { @@ -66,6 +67,7 @@ usb30: usb@11270000 { usb3-lpm-capable; mediatek,syscon-wakeup = <&pericfg>; mediatek,wakeup-src = <1>; + imod-interval-ns = <10000>; }; 2nd: dual-role mode with xHCI driver --- a/Documentation/devicetree/bindings/usb/usb-xhci.txt +++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt @@ -29,6 +29,7 @@ Optional properties: - clocks: reference to a clock - usb3-lpm-capable: determines if platform is USB3 LPM capable - quirk-broken-port-ped: set if the controller has broken port disable mechanism + - imod-interval-ns: default interrupt moderation interval is 5000ns Example: usb@f0931000 { --- a/drivers/usb/host/xhci-mtk.c +++ b/drivers/usb/host/xhci-mtk.c @@ -629,6 +629,15 @@ static int xhci_mtk_probe(struct platfor xhci = hcd_to_xhci(hcd); xhci->main_hcd = hcd; + + /* + * imod_interval is the interrupt moderation value in nanoseconds. + * The increment interval is 8 times as much as that defined in + * the xHCI spec on MTK's controller. + */ + xhci->imod_interval = 5000; + device_property_read_u32(dev, "imod-interval-ns", &xhci->imod_interval); + xhci->shared_hcd = usb_create_shared_hcd(driver, dev, dev_name(dev), hcd); if (!xhci->shared_hcd) { --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -283,6 +283,9 @@ static int xhci_pci_setup(struct usb_hcd if (!xhci->sbrn) pci_read_config_byte(pdev, XHCI_SBRN_OFFSET, &xhci->sbrn); + /* imod_interval is the interrupt moderation value in nanoseconds. */ + xhci->imod_interval = 40000; + retval = xhci_gen_setup(hcd, xhci_pci_quirks); if (retval) return retval; --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -269,6 +269,11 @@ static int xhci_plat_probe(struct platfo if (device_property_read_bool(&pdev->dev, "quirk-broken-port-ped")) xhci->quirks |= XHCI_BROKEN_PORT_PED; + /* imod_interval is the interrupt moderation value in nanoseconds. */ + xhci->imod_interval = 40000; + device_property_read_u32(sysdev, "imod-interval-ns", + &xhci->imod_interval); + hcd->usb_phy = devm_usb_get_phy_by_phandle(sysdev, "usb-phy", 0); if (IS_ERR(hcd->usb_phy)) { ret = PTR_ERR(hcd->usb_phy); --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -610,11 +610,7 @@ int xhci_run(struct usb_hcd *hcd) "// Set the interrupt modulation register"); temp = readl(&xhci->ir_set->irq_control); temp &= ~ER_IRQ_INTERVAL_MASK; - /* - * the increment interval is 8 times as much as that defined - * in xHCI spec on MTK's controller - */ - temp |= (u32) ((xhci->quirks & XHCI_MTK_HOST) ? 20 : 160); + temp |= (xhci->imod_interval / 250) & ER_IRQ_INTERVAL_MASK; writel(temp, &xhci->ir_set->irq_control); /* Set the HCD state before we enable the irqs */ --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1730,6 +1730,8 @@ struct xhci_hcd { u8 max_interrupters; u8 max_ports; u8 isoc_threshold; + /* imod_interval in ns (I * 250ns) */ + u32 imod_interval; int event_ring_max; /* 4KB min, 128MB max */ int page_size;