/* * EHCI HCD (Host Controller Driver) for USB. * * Bus Glue for Xilinx EHCI core on the of_platform bus * * Copyright (c) 2009 Xilinx, Inc. * * Based on "ehci-ppc-of.c" by Valentine Barshak * and "ehci-ppc-soc.c" by Stefan Roese * and "ohci-ppc-of.c" by Sylvain Munaut * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * */ #include #include #include #include #include #include /** * ehci_xilinx_port_handed_over - hand the port out if failed to enable it * @hcd: Pointer to the usb_hcd device to which the host controller bound * @portnum:Port number to which the device is attached. * * This function is used as a place to tell the user that the Xilinx USB host * controller does support LS devices. And in an HS only configuration, it * does not support FS devices either. It is hoped that this can help a * confused user. * * There are cases when the host controller fails to enable the port due to, * for example, insufficient power that can be supplied to the device from * the USB bus. In those cases, the messages printed here are not helpful. */ static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum) { dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum); if (hcd->has_tt) { dev_warn(hcd->self.controller, "Maybe you have connected a low speed device?\n"); dev_warn(hcd->self.controller, "We do not support low speed devices\n"); } else { dev_warn(hcd->self.controller, "Maybe your device is not a high speed device?\n"); dev_warn(hcd->self.controller, "The USB host controller does not support full speed " "nor low speed devices\n"); dev_warn(hcd->self.controller, "You can reconfigure the host controller to have " "full speed support\n"); } return 0; } static const struct hc_driver ehci_xilinx_of_hc_driver = { .description = hcd_name, .product_desc = "OF EHCI", .hcd_priv_size = sizeof(struct ehci_hcd), /* * generic hardware linkage */ .irq = ehci_irq, .flags = HCD_MEMORY | HCD_USB2 | HCD_BH, /* * basic lifecycle operations */ .reset = ehci_setup, .start = ehci_run, .stop = ehci_stop, .shutdown = ehci_shutdown, /* * managing i/o requests and associated device resources */ .urb_enqueue = ehci_urb_enqueue, .urb_dequeue = ehci_urb_dequeue, .endpoint_disable = ehci_endpoint_disable, .endpoint_reset = ehci_endpoint_reset, /* * scheduling support */ .get_frame_number = ehci_get_frame, /* * root hub support */ .hub_status_data = ehci_hub_status_data, .hub_control = ehci_hub_control, #ifdef CONFIG_PM .bus_suspend = ehci_bus_suspend, .bus_resume = ehci_bus_resume, #endif .relinquish_port = NULL, .port_handed_over = ehci_xilinx_port_handed_over, .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete, }; /** * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller * @op: pointer to the platform_device bound to the host controller * * This function requests resources and sets up appropriate properties for the * host controller. Because the Xilinx USB host controller can be configured * as HS only or HS/FS only, it checks the configuration in the device tree * entry, and sets an appropriate value for hcd->has_tt. */ static int ehci_hcd_xilinx_of_probe(struct platform_device *op) { struct device_node *dn = op->dev.of_node; struct usb_hcd *hcd; struct ehci_hcd *ehci; struct resource res; int irq; int rv; int *value; if (usb_disabled()) return -ENODEV; dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n"); rv = of_address_to_resource(dn, 0, &res); if (rv) return rv; hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev, "XILINX-OF USB"); if (!hcd) return -ENOMEM; hcd->rsrc_start = res.start; hcd->rsrc_len = resource_size(&res); irq = irq_of_parse_and_map(dn, 0); if (!irq) { dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n", __FILE__); rv = -EBUSY; goto err_irq; } hcd->regs = devm_ioremap_resource(&op->dev, &res); if (IS_ERR(hcd->regs)) { rv = PTR_ERR(hcd->regs); goto err_irq; } ehci = hcd_to_ehci(hcd); /* This core always has big-endian register interface and uses * big-endian memory descriptors. */ ehci->big_endian_mmio = 1; ehci->big_endian_desc = 1; /* Check whether the FS support option is selected in the hardware. */ value = (int *)of_get_property(dn, "xlnx,support-usb-fs", NULL); if (value && (*value == 1)) { ehci_dbg(ehci, "USB host controller supports FS devices\n"); hcd->has_tt = 1; } else { ehci_dbg(ehci, "USB host controller is HS only\n"); hcd->has_tt = 0; } /* Debug registers are at the first 0x100 region */ ehci->caps = hcd->regs + 0x100; rv = usb_add_hcd(hcd, irq, 0); if (rv == 0) { device_wakeup_enable(hcd->self.controller); return 0; } err_irq: usb_put_hcd(hcd); return rv; } /** * ehci_hcd_xilinx_of_remove - shutdown hcd and release resources * @op: pointer to platform_device structure that is to be removed * * Remove the hcd structure, and release resources that has been requested * during probe. */ static int ehci_hcd_xilinx_of_remove(struct platform_device *op) { struct usb_hcd *hcd = platform_get_drvdata(op); dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n"); usb_remove_hcd(hcd); usb_put_hcd(hcd); return 0; } static const struct of_device_id ehci_hcd_xilinx_of_match[] = { {.compatible = "xlnx,xps-usb-host-1.00.a",}, {}, }; MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match); static struct platform_driver ehci_hcd_xilinx_of_driver = { .probe = ehci_hcd_xilinx_of_probe, .remove = ehci_hcd_xilinx_of_remove, .shutdown = usb_hcd_platform_shutdown, .driver = { .name = "xilinx-of-ehci", .of_match_table = ehci_hcd_xilinx_of_match, }, }; subject'>x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'drivers/usb/host/sl811-hcd.c')