linux/drivers/usb/dwc2/core.c

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// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
* core.c - DesignWare HS OTG Controller common routines
*
* Copyright (C) 2004-2013 Synopsys, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The names of the above-listed copyright holders may not be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* ALTERNATIVELY, this software may be distributed under the terms of the
* GNU General Public License ("GPL") as published by the Free Software
* Foundation; either version 2 of the License, or (at your option) any
* later version.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* The Core code provides basic services for accessing and managing the
* DWC_otg hardware. These services are used by both the Host Controller
* Driver and the Peripheral Controller Driver.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/usb/ch11.h>
#include "core.h"
#include "hcd.h"
/**
* dwc2_backup_global_registers() - Backup global controller registers.
* When suspending usb bus, registers needs to be backuped
* if controller power is disabled once suspended.
*
* @hsotg: Programming view of the DWC_otg controller
*/
static int dwc2_backup_global_registers(struct dwc2_hsotg *hsotg)
{
struct dwc2_gregs_backup *gr;
int i;
/* Backup global regs */
gr = &hsotg->gr_backup;
gr->gotgctl = dwc2_readl(hsotg->regs + GOTGCTL);
gr->gintmsk = dwc2_readl(hsotg->regs + GINTMSK);
gr->gahbcfg = dwc2_readl(hsotg->regs + GAHBCFG);
gr->gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
gr->grxfsiz = dwc2_readl(hsotg->regs + GRXFSIZ);
gr->gnptxfsiz = dwc2_readl(hsotg->regs + GNPTXFSIZ);
gr->hptxfsiz = dwc2_readl(hsotg->regs + HPTXFSIZ);
gr->gdfifocfg = dwc2_readl(hsotg->regs + GDFIFOCFG);
for (i = 0; i < MAX_EPS_CHANNELS; i++)
gr->dtxfsiz[i] = dwc2_readl(hsotg->regs + DPTXFSIZN(i));
gr->valid = true;
return 0;
}
/**
* dwc2_restore_global_registers() - Restore controller global registers.
* When resuming usb bus, device registers needs to be restored
* if controller power were disabled.
*
* @hsotg: Programming view of the DWC_otg controller
*/
static int dwc2_restore_global_registers(struct dwc2_hsotg *hsotg)
{
struct dwc2_gregs_backup *gr;
int i;
dev_dbg(hsotg->dev, "%s\n", __func__);
/* Restore global regs */
gr = &hsotg->gr_backup;
if (!gr->valid) {
dev_err(hsotg->dev, "%s: no global registers to restore\n",
__func__);
return -EINVAL;
}
gr->valid = false;
dwc2_writel(0xffffffff, hsotg->regs + GINTSTS);
dwc2_writel(gr->gotgctl, hsotg->regs + GOTGCTL);
dwc2_writel(gr->gintmsk, hsotg->regs + GINTMSK);
dwc2_writel(gr->gusbcfg, hsotg->regs + GUSBCFG);
dwc2_writel(gr->gahbcfg, hsotg->regs + GAHBCFG);
dwc2_writel(gr->grxfsiz, hsotg->regs + GRXFSIZ);
dwc2_writel(gr->gnptxfsiz, hsotg->regs + GNPTXFSIZ);
dwc2_writel(gr->hptxfsiz, hsotg->regs + HPTXFSIZ);
dwc2_writel(gr->gdfifocfg, hsotg->regs + GDFIFOCFG);
for (i = 0; i < MAX_EPS_CHANNELS; i++)
dwc2_writel(gr->dtxfsiz[i], hsotg->regs + DPTXFSIZN(i));
return 0;
}
/**
* dwc2_exit_hibernation() - Exit controller from Partial Power Down.
*
* @hsotg: Programming view of the DWC_otg controller
* @restore: Controller registers need to be restored
*/
int dwc2_exit_hibernation(struct dwc2_hsotg *hsotg, bool restore)
{
u32 pcgcctl;
int ret = 0;
if (!hsotg->params.hibernation)
return -ENOTSUPP;
pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
pcgcctl &= ~PCGCTL_STOPPCLK;
dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
pcgcctl &= ~PCGCTL_PWRCLMP;
dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
pcgcctl &= ~PCGCTL_RSTPDWNMODULE;
dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
udelay(100);
if (restore) {
ret = dwc2_restore_global_registers(hsotg);
if (ret) {
dev_err(hsotg->dev, "%s: failed to restore registers\n",
__func__);
return ret;
}
if (dwc2_is_host_mode(hsotg)) {
ret = dwc2_restore_host_registers(hsotg);
if (ret) {
dev_err(hsotg->dev, "%s: failed to restore host registers\n",
__func__);
return ret;
}
} else {
ret = dwc2_restore_device_registers(hsotg);
if (ret) {
dev_err(hsotg->dev, "%s: failed to restore device registers\n",
__func__);
return ret;
}
}
}
return ret;
}
/**
* dwc2_enter_hibernation() - Put controller in Partial Power Down.
*
* @hsotg: Programming view of the DWC_otg controller
*/
int dwc2_enter_hibernation(struct dwc2_hsotg *hsotg)
{
u32 pcgcctl;
int ret = 0;
if (!hsotg->params.hibernation)
return -ENOTSUPP;
/* Backup all registers */
ret = dwc2_backup_global_registers(hsotg);
if (ret) {
dev_err(hsotg->dev, "%s: failed to backup global registers\n",
__func__);
return ret;
}
if (dwc2_is_host_mode(hsotg)) {
ret = dwc2_backup_host_registers(hsotg);
if (ret) {
dev_err(hsotg->dev, "%s: failed to backup host registers\n",
__func__);
return ret;
}
} else {
ret = dwc2_backup_device_registers(hsotg);
if (ret) {
dev_err(hsotg->dev, "%s: failed to backup device registers\n",
__func__);
return ret;
}
}
/*
* Clear any pending interrupts since dwc2 will not be able to
* clear them after entering hibernation.
*/
dwc2_writel(0xffffffff, hsotg->regs + GINTSTS);
/* Put the controller in low power state */
pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
pcgcctl |= PCGCTL_PWRCLMP;
dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
ndelay(20);
pcgcctl |= PCGCTL_RSTPDWNMODULE;
dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
ndelay(20);
pcgcctl |= PCGCTL_STOPPCLK;
dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
return ret;
}
/**
* dwc2_wait_for_mode() - Waits for the controller mode.
* @hsotg: Programming view of the DWC_otg controller.
* @host_mode: If true, waits for host mode, otherwise device mode.
*/
static void dwc2_wait_for_mode(struct dwc2_hsotg *hsotg,
bool host_mode)
{
ktime_t start;
ktime_t end;
unsigned int timeout = 110;
dev_vdbg(hsotg->dev, "Waiting for %s mode\n",
host_mode ? "host" : "device");
start = ktime_get();
while (1) {
s64 ms;
if (dwc2_is_host_mode(hsotg) == host_mode) {
dev_vdbg(hsotg->dev, "%s mode set\n",
host_mode ? "Host" : "Device");
break;
}
end = ktime_get();
ms = ktime_to_ms(ktime_sub(end, start));
if (ms >= (s64)timeout) {
dev_warn(hsotg->dev, "%s: Couldn't set %s mode\n",
__func__, host_mode ? "host" : "device");
break;
}
usleep_range(1000, 2000);
}
}
/**
* dwc2_iddig_filter_enabled() - Returns true if the IDDIG debounce
* filter is enabled.
*/
static bool dwc2_iddig_filter_enabled(struct dwc2_hsotg *hsotg)
{
u32 gsnpsid;
u32 ghwcfg4;
if (!dwc2_hw_is_otg(hsotg))
return false;
/* Check if core configuration includes the IDDIG filter. */
ghwcfg4 = dwc2_readl(hsotg->regs + GHWCFG4);
if (!(ghwcfg4 & GHWCFG4_IDDIG_FILT_EN))
return false;
/*
* Check if the IDDIG debounce filter is bypassed. Available
* in core version >= 3.10a.
*/
gsnpsid = dwc2_readl(hsotg->regs + GSNPSID);
if (gsnpsid >= DWC2_CORE_REV_3_10a) {
u32 gotgctl = dwc2_readl(hsotg->regs + GOTGCTL);
if (gotgctl & GOTGCTL_DBNCE_FLTR_BYPASS)
return false;
}
return true;
}
/*
* Do core a soft reset of the core. Be careful with this because it
* resets all the internal state machines of the core.
*/
usb: dwc2: Avoid sleeping while holding hsotg->lock Basically when plugging in various cables in different orders, I'm occasionally seeing the following BUG splat: [ 86.215403] BUG: scheduling while atomic: kworker/u16:2/53/0x00000002 [ 86.219164] usb 1-1: USB disconnect, device number 9 [ 86.226845] Preemption disabled at:[ 86.230218] [<ffffff8008673558>] dwc2_conn_id_status_change+0x120/0x250 [ 86.236894] CPU: 0 PID: 53 Comm: kworker/u16:2 Tainted: G W 4.9.0-rc8-00051-gd5a7979-dirty #1702 [ 86.246836] Hardware name: HiKey Development Board (DT) [ 86.252100] Workqueue: dwc2 dwc2_conn_id_status_change [ 86.257279] Call trace: [ 86.259771] [<ffffff8008087c28>] dump_backtrace+0x0/0x1a0 [ 86.265210] [<ffffff8008087ddc>] show_stack+0x14/0x20 [ 86.270308] [<ffffff80084343f0>] dump_stack+0x90/0xb0 [ 86.275401] [<ffffff80080d8d94>] __schedule_bug+0x6c/0xb8 [ 86.280841] [<ffffff8008a07220>] __schedule+0x4f8/0x5b0 [ 86.286099] [<ffffff8008a073e8>] schedule+0x38/0xa0 [ 86.291017] [<ffffff8008a0a6cc>] schedule_hrtimeout_range_clock+0x8c/0xf0 [ 86.297846] [<ffffff8008a0a740>] schedule_hrtimeout_range+0x10/0x18 [ 86.304150] [<ffffff8008a0a4a0>] usleep_range+0x50/0x58 [ 86.309418] [<ffffff800866d8dc>] dwc2_wait_for_mode.isra.4+0x54/0xd0 [ 86.315815] [<ffffff800866f058>] dwc2_core_reset+0xe0/0x168 [ 86.321431] [<ffffff800867e364>] dwc2_hsotg_core_init_disconnected+0x2c/0x310 [ 86.328602] [<ffffff8008673568>] dwc2_conn_id_status_change+0x130/0x250 [ 86.335254] [<ffffff80080ccd48>] process_one_work+0x118/0x370 [ 86.341035] [<ffffff80080ccfe8>] worker_thread+0x48/0x498 [ 86.346473] [<ffffff80080d2eb0>] kthread+0xd0/0xe8 [ 86.351299] [<ffffff8008082e80>] ret_from_fork+0x10/0x50 This seems to be caused by the dwc2_wait_for_mode() calling usleep_range() while the hstog->lock spinlock is held, since we take that before calling dwc2_hsotg_core_init_disconnected(). This patch avoids the issue by adding an extra argument to dwc2_core_reset(), as suggested by John Youn, which allows us to skip the waiting, which should be unnecessary when calling from dwc2_hsotg_core_init_disconnected(). Cc: Wei Xu <xuwei5@hisilicon.com> Cc: Guodong Xu <guodong.xu@linaro.org> Cc: Amit Pundir <amit.pundir@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: John Youn <johnyoun@synopsys.com> Cc: Douglas Anderson <dianders@chromium.org> Cc: Chen Yu <chenyu56@huawei.com> Cc: Vardan Mikayelyan <mvardan@synopsys.com> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-usb@vger.kernel.org Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2017-01-23 22:59:14 +00:00
int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait)
{
u32 greset;
int count = 0;
bool wait_for_host_mode = false;
dev_vdbg(hsotg->dev, "%s()\n", __func__);
/*
* If the current mode is host, either due to the force mode
* bit being set (which persists after core reset) or the
* connector id pin, a core soft reset will temporarily reset
* the mode to device. A delay from the IDDIG debounce filter
* will occur before going back to host mode.
*
* Determine whether we will go back into host mode after a
* reset and account for this delay after the reset.
*/
if (dwc2_iddig_filter_enabled(hsotg)) {
u32 gotgctl = dwc2_readl(hsotg->regs + GOTGCTL);
u32 gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
if (!(gotgctl & GOTGCTL_CONID_B) ||
(gusbcfg & GUSBCFG_FORCEHOSTMODE)) {
wait_for_host_mode = true;
}
}
/* Core Soft Reset */
greset = dwc2_readl(hsotg->regs + GRSTCTL);
greset |= GRSTCTL_CSFTRST;
dwc2_writel(greset, hsotg->regs + GRSTCTL);
do {
udelay(1);
greset = dwc2_readl(hsotg->regs + GRSTCTL);
if (++count > 50) {
dev_warn(hsotg->dev,
"%s() HANG! Soft Reset GRSTCTL=%0x\n",
__func__, greset);
return -EBUSY;
}
} while (greset & GRSTCTL_CSFTRST);
/* Wait for AHB master IDLE state */
count = 0;
do {
udelay(1);
greset = dwc2_readl(hsotg->regs + GRSTCTL);
if (++count > 50) {
dev_warn(hsotg->dev,
"%s() HANG! AHB Idle GRSTCTL=%0x\n",
__func__, greset);
return -EBUSY;
}
} while (!(greset & GRSTCTL_AHBIDLE));
usb: dwc2: Avoid sleeping while holding hsotg->lock Basically when plugging in various cables in different orders, I'm occasionally seeing the following BUG splat: [ 86.215403] BUG: scheduling while atomic: kworker/u16:2/53/0x00000002 [ 86.219164] usb 1-1: USB disconnect, device number 9 [ 86.226845] Preemption disabled at:[ 86.230218] [<ffffff8008673558>] dwc2_conn_id_status_change+0x120/0x250 [ 86.236894] CPU: 0 PID: 53 Comm: kworker/u16:2 Tainted: G W 4.9.0-rc8-00051-gd5a7979-dirty #1702 [ 86.246836] Hardware name: HiKey Development Board (DT) [ 86.252100] Workqueue: dwc2 dwc2_conn_id_status_change [ 86.257279] Call trace: [ 86.259771] [<ffffff8008087c28>] dump_backtrace+0x0/0x1a0 [ 86.265210] [<ffffff8008087ddc>] show_stack+0x14/0x20 [ 86.270308] [<ffffff80084343f0>] dump_stack+0x90/0xb0 [ 86.275401] [<ffffff80080d8d94>] __schedule_bug+0x6c/0xb8 [ 86.280841] [<ffffff8008a07220>] __schedule+0x4f8/0x5b0 [ 86.286099] [<ffffff8008a073e8>] schedule+0x38/0xa0 [ 86.291017] [<ffffff8008a0a6cc>] schedule_hrtimeout_range_clock+0x8c/0xf0 [ 86.297846] [<ffffff8008a0a740>] schedule_hrtimeout_range+0x10/0x18 [ 86.304150] [<ffffff8008a0a4a0>] usleep_range+0x50/0x58 [ 86.309418] [<ffffff800866d8dc>] dwc2_wait_for_mode.isra.4+0x54/0xd0 [ 86.315815] [<ffffff800866f058>] dwc2_core_reset+0xe0/0x168 [ 86.321431] [<ffffff800867e364>] dwc2_hsotg_core_init_disconnected+0x2c/0x310 [ 86.328602] [<ffffff8008673568>] dwc2_conn_id_status_change+0x130/0x250 [ 86.335254] [<ffffff80080ccd48>] process_one_work+0x118/0x370 [ 86.341035] [<ffffff80080ccfe8>] worker_thread+0x48/0x498 [ 86.346473] [<ffffff80080d2eb0>] kthread+0xd0/0xe8 [ 86.351299] [<ffffff8008082e80>] ret_from_fork+0x10/0x50 This seems to be caused by the dwc2_wait_for_mode() calling usleep_range() while the hstog->lock spinlock is held, since we take that before calling dwc2_hsotg_core_init_disconnected(). This patch avoids the issue by adding an extra argument to dwc2_core_reset(), as suggested by John Youn, which allows us to skip the waiting, which should be unnecessary when calling from dwc2_hsotg_core_init_disconnected(). Cc: Wei Xu <xuwei5@hisilicon.com> Cc: Guodong Xu <guodong.xu@linaro.org> Cc: Amit Pundir <amit.pundir@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: John Youn <johnyoun@synopsys.com> Cc: Douglas Anderson <dianders@chromium.org> Cc: Chen Yu <chenyu56@huawei.com> Cc: Vardan Mikayelyan <mvardan@synopsys.com> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-usb@vger.kernel.org Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2017-01-23 22:59:14 +00:00
if (wait_for_host_mode && !skip_wait)
dwc2_wait_for_mode(hsotg, true);
return 0;
}
/*
* Force the mode of the controller.
*
* Forcing the mode is needed for two cases:
*
* 1) If the dr_mode is set to either HOST or PERIPHERAL we force the
* controller to stay in a particular mode regardless of ID pin
* changes. We do this usually after a core reset.
*
* 2) During probe we want to read reset values of the hw
* configuration registers that are only available in either host or
* device mode. We may need to force the mode if the current mode does
* not allow us to access the register in the mode that we want.
*
* In either case it only makes sense to force the mode if the
* controller hardware is OTG capable.
*
* Checks are done in this function to determine whether doing a force
* would be valid or not.
*
* If a force is done, it requires a IDDIG debounce filter delay if
* the filter is configured and enabled. We poll the current mode of
* the controller to account for this delay.
*/
static bool dwc2_force_mode(struct dwc2_hsotg *hsotg, bool host)
{
u32 gusbcfg;
u32 set;
u32 clear;
dev_dbg(hsotg->dev, "Forcing mode to %s\n", host ? "host" : "device");
/*
* Force mode has no effect if the hardware is not OTG.
*/
if (!dwc2_hw_is_otg(hsotg))
return false;
/*
* If dr_mode is either peripheral or host only, there is no
* need to ever force the mode to the opposite mode.
*/
if (WARN_ON(host && hsotg->dr_mode == USB_DR_MODE_PERIPHERAL))
return false;
if (WARN_ON(!host && hsotg->dr_mode == USB_DR_MODE_HOST))
return false;
gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
set = host ? GUSBCFG_FORCEHOSTMODE : GUSBCFG_FORCEDEVMODE;
clear = host ? GUSBCFG_FORCEDEVMODE : GUSBCFG_FORCEHOSTMODE;
gusbcfg &= ~clear;
gusbcfg |= set;
dwc2_writel(gusbcfg, hsotg->regs + GUSBCFG);
dwc2_wait_for_mode(hsotg, host);
return true;
}
/**
* dwc2_clear_force_mode() - Clears the force mode bits.
*
* After clearing the bits, wait up to 100 ms to account for any
* potential IDDIG filter delay. We can't know if we expect this delay
* or not because the value of the connector ID status is affected by
* the force mode. We only need to call this once during probe if
* dr_mode == OTG.
*/
void dwc2_clear_force_mode(struct dwc2_hsotg *hsotg)
{
u32 gusbcfg;
gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
gusbcfg &= ~GUSBCFG_FORCEHOSTMODE;
gusbcfg &= ~GUSBCFG_FORCEDEVMODE;
dwc2_writel(gusbcfg, hsotg->regs + GUSBCFG);
if (dwc2_iddig_filter_enabled(hsotg))
msleep(100);
}
/*
* Sets or clears force mode based on the dr_mode parameter.
*/
void dwc2_force_dr_mode(struct dwc2_hsotg *hsotg)
{
bool ret;
switch (hsotg->dr_mode) {
case USB_DR_MODE_HOST:
ret = dwc2_force_mode(hsotg, true);
/*
* NOTE: This is required for some rockchip soc based
* platforms on their host-only dwc2.
*/
if (!ret)
msleep(50);
break;
case USB_DR_MODE_PERIPHERAL:
dwc2_force_mode(hsotg, false);
break;
case USB_DR_MODE_OTG:
dwc2_clear_force_mode(hsotg);
break;
default:
dev_warn(hsotg->dev, "%s() Invalid dr_mode=%d\n",
__func__, hsotg->dr_mode);
break;
}
}
/*
* Do core a soft reset of the core. Be careful with this because it
* resets all the internal state machines of the core.
*
* Additionally this will apply force mode as per the hsotg->dr_mode
* parameter.
*/
int dwc2_core_reset_and_force_dr_mode(struct dwc2_hsotg *hsotg)
{
int retval;
usb: dwc2: Avoid sleeping while holding hsotg->lock Basically when plugging in various cables in different orders, I'm occasionally seeing the following BUG splat: [ 86.215403] BUG: scheduling while atomic: kworker/u16:2/53/0x00000002 [ 86.219164] usb 1-1: USB disconnect, device number 9 [ 86.226845] Preemption disabled at:[ 86.230218] [<ffffff8008673558>] dwc2_conn_id_status_change+0x120/0x250 [ 86.236894] CPU: 0 PID: 53 Comm: kworker/u16:2 Tainted: G W 4.9.0-rc8-00051-gd5a7979-dirty #1702 [ 86.246836] Hardware name: HiKey Development Board (DT) [ 86.252100] Workqueue: dwc2 dwc2_conn_id_status_change [ 86.257279] Call trace: [ 86.259771] [<ffffff8008087c28>] dump_backtrace+0x0/0x1a0 [ 86.265210] [<ffffff8008087ddc>] show_stack+0x14/0x20 [ 86.270308] [<ffffff80084343f0>] dump_stack+0x90/0xb0 [ 86.275401] [<ffffff80080d8d94>] __schedule_bug+0x6c/0xb8 [ 86.280841] [<ffffff8008a07220>] __schedule+0x4f8/0x5b0 [ 86.286099] [<ffffff8008a073e8>] schedule+0x38/0xa0 [ 86.291017] [<ffffff8008a0a6cc>] schedule_hrtimeout_range_clock+0x8c/0xf0 [ 86.297846] [<ffffff8008a0a740>] schedule_hrtimeout_range+0x10/0x18 [ 86.304150] [<ffffff8008a0a4a0>] usleep_range+0x50/0x58 [ 86.309418] [<ffffff800866d8dc>] dwc2_wait_for_mode.isra.4+0x54/0xd0 [ 86.315815] [<ffffff800866f058>] dwc2_core_reset+0xe0/0x168 [ 86.321431] [<ffffff800867e364>] dwc2_hsotg_core_init_disconnected+0x2c/0x310 [ 86.328602] [<ffffff8008673568>] dwc2_conn_id_status_change+0x130/0x250 [ 86.335254] [<ffffff80080ccd48>] process_one_work+0x118/0x370 [ 86.341035] [<ffffff80080ccfe8>] worker_thread+0x48/0x498 [ 86.346473] [<ffffff80080d2eb0>] kthread+0xd0/0xe8 [ 86.351299] [<ffffff8008082e80>] ret_from_fork+0x10/0x50 This seems to be caused by the dwc2_wait_for_mode() calling usleep_range() while the hstog->lock spinlock is held, since we take that before calling dwc2_hsotg_core_init_disconnected(). This patch avoids the issue by adding an extra argument to dwc2_core_reset(), as suggested by John Youn, which allows us to skip the waiting, which should be unnecessary when calling from dwc2_hsotg_core_init_disconnected(). Cc: Wei Xu <xuwei5@hisilicon.com> Cc: Guodong Xu <guodong.xu@linaro.org> Cc: Amit Pundir <amit.pundir@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: John Youn <johnyoun@synopsys.com> Cc: Douglas Anderson <dianders@chromium.org> Cc: Chen Yu <chenyu56@huawei.com> Cc: Vardan Mikayelyan <mvardan@synopsys.com> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-usb@vger.kernel.org Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2017-01-23 22:59:14 +00:00
retval = dwc2_core_reset(hsotg, false);
if (retval)
return retval;
dwc2_force_dr_mode(hsotg);
return 0;
}
/**
* dwc2_dump_host_registers() - Prints the host registers
*
* @hsotg: Programming view of DWC_otg controller
*
* NOTE: This function will be removed once the peripheral controller code
* is integrated and the driver is stable
*/
void dwc2_dump_host_registers(struct dwc2_hsotg *hsotg)
{
#ifdef DEBUG
u32 __iomem *addr;
int i;
dev_dbg(hsotg->dev, "Host Global Registers\n");
addr = hsotg->regs + HCFG;
dev_dbg(hsotg->dev, "HCFG @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HFIR;
dev_dbg(hsotg->dev, "HFIR @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HFNUM;
dev_dbg(hsotg->dev, "HFNUM @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HPTXSTS;
dev_dbg(hsotg->dev, "HPTXSTS @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HAINT;
dev_dbg(hsotg->dev, "HAINT @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HAINTMSK;
dev_dbg(hsotg->dev, "HAINTMSK @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
if (hsotg->params.dma_desc_enable) {
addr = hsotg->regs + HFLBADDR;
dev_dbg(hsotg->dev, "HFLBADDR @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
}
addr = hsotg->regs + HPRT0;
dev_dbg(hsotg->dev, "HPRT0 @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
for (i = 0; i < hsotg->params.host_channels; i++) {
dev_dbg(hsotg->dev, "Host Channel %d Specific Registers\n", i);
addr = hsotg->regs + HCCHAR(i);
dev_dbg(hsotg->dev, "HCCHAR @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HCSPLT(i);
dev_dbg(hsotg->dev, "HCSPLT @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HCINT(i);
dev_dbg(hsotg->dev, "HCINT @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HCINTMSK(i);
dev_dbg(hsotg->dev, "HCINTMSK @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HCTSIZ(i);
dev_dbg(hsotg->dev, "HCTSIZ @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HCDMA(i);
dev_dbg(hsotg->dev, "HCDMA @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
if (hsotg->params.dma_desc_enable) {
addr = hsotg->regs + HCDMAB(i);
dev_dbg(hsotg->dev, "HCDMAB @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
}
}
#endif
}
/**
* dwc2_dump_global_registers() - Prints the core global registers
*
* @hsotg: Programming view of DWC_otg controller
*
* NOTE: This function will be removed once the peripheral controller code
* is integrated and the driver is stable
*/
void dwc2_dump_global_registers(struct dwc2_hsotg *hsotg)
{
#ifdef DEBUG
u32 __iomem *addr;
dev_dbg(hsotg->dev, "Core Global Registers\n");
addr = hsotg->regs + GOTGCTL;
dev_dbg(hsotg->dev, "GOTGCTL @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GOTGINT;
dev_dbg(hsotg->dev, "GOTGINT @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GAHBCFG;
dev_dbg(hsotg->dev, "GAHBCFG @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GUSBCFG;
dev_dbg(hsotg->dev, "GUSBCFG @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GRSTCTL;
dev_dbg(hsotg->dev, "GRSTCTL @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GINTSTS;
dev_dbg(hsotg->dev, "GINTSTS @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GINTMSK;
dev_dbg(hsotg->dev, "GINTMSK @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GRXSTSR;
dev_dbg(hsotg->dev, "GRXSTSR @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GRXFSIZ;
dev_dbg(hsotg->dev, "GRXFSIZ @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GNPTXFSIZ;
dev_dbg(hsotg->dev, "GNPTXFSIZ @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GNPTXSTS;
dev_dbg(hsotg->dev, "GNPTXSTS @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GI2CCTL;
dev_dbg(hsotg->dev, "GI2CCTL @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GPVNDCTL;
dev_dbg(hsotg->dev, "GPVNDCTL @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GGPIO;
dev_dbg(hsotg->dev, "GGPIO @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GUID;
dev_dbg(hsotg->dev, "GUID @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GSNPSID;
dev_dbg(hsotg->dev, "GSNPSID @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GHWCFG1;
dev_dbg(hsotg->dev, "GHWCFG1 @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GHWCFG2;
dev_dbg(hsotg->dev, "GHWCFG2 @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GHWCFG3;
dev_dbg(hsotg->dev, "GHWCFG3 @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GHWCFG4;
dev_dbg(hsotg->dev, "GHWCFG4 @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GLPMCFG;
dev_dbg(hsotg->dev, "GLPMCFG @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GPWRDN;
dev_dbg(hsotg->dev, "GPWRDN @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + GDFIFOCFG;
dev_dbg(hsotg->dev, "GDFIFOCFG @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + HPTXFSIZ;
dev_dbg(hsotg->dev, "HPTXFSIZ @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
addr = hsotg->regs + PCGCTL;
dev_dbg(hsotg->dev, "PCGCTL @0x%08lX : 0x%08X\n",
(unsigned long)addr, dwc2_readl(addr));
#endif
}
/**
* dwc2_flush_tx_fifo() - Flushes a Tx FIFO
*
* @hsotg: Programming view of DWC_otg controller
* @num: Tx FIFO to flush
*/
void dwc2_flush_tx_fifo(struct dwc2_hsotg *hsotg, const int num)
{
u32 greset;
int count = 0;
dev_vdbg(hsotg->dev, "Flush Tx FIFO %d\n", num);
greset = GRSTCTL_TXFFLSH;
greset |= num << GRSTCTL_TXFNUM_SHIFT & GRSTCTL_TXFNUM_MASK;
dwc2_writel(greset, hsotg->regs + GRSTCTL);
do {
greset = dwc2_readl(hsotg->regs + GRSTCTL);
if (++count > 10000) {
dev_warn(hsotg->dev,
"%s() HANG! GRSTCTL=%0x GNPTXSTS=0x%08x\n",
__func__, greset,
dwc2_readl(hsotg->regs + GNPTXSTS));
break;
}
udelay(1);
} while (greset & GRSTCTL_TXFFLSH);
/* Wait for at least 3 PHY Clocks */
udelay(1);
}
/**
* dwc2_flush_rx_fifo() - Flushes the Rx FIFO
*
* @hsotg: Programming view of DWC_otg controller
*/
void dwc2_flush_rx_fifo(struct dwc2_hsotg *hsotg)
{
u32 greset;
int count = 0;
dev_vdbg(hsotg->dev, "%s()\n", __func__);
greset = GRSTCTL_RXFFLSH;
dwc2_writel(greset, hsotg->regs + GRSTCTL);
do {
greset = dwc2_readl(hsotg->regs + GRSTCTL);
if (++count > 10000) {
dev_warn(hsotg->dev, "%s() HANG! GRSTCTL=%0x\n",
__func__, greset);
break;
}
udelay(1);
} while (greset & GRSTCTL_RXFFLSH);
/* Wait for at least 3 PHY Clocks */
udelay(1);
}
/*
* Forces either host or device mode if the controller is not
* currently in that mode.
*
* Returns true if the mode was forced.
*/
bool dwc2_force_mode_if_needed(struct dwc2_hsotg *hsotg, bool host)
{
if (host && dwc2_is_host_mode(hsotg))
return false;
else if (!host && dwc2_is_device_mode(hsotg))
return false;
return dwc2_force_mode(hsotg, host);
}
bool dwc2_is_controller_alive(struct dwc2_hsotg *hsotg)
{
if (dwc2_readl(hsotg->regs + GSNPSID) == 0xffffffff)
return false;
else
return true;
}
/**
* dwc2_enable_global_interrupts() - Enables the controller's Global
* Interrupt in the AHB Config register
*
* @hsotg: Programming view of DWC_otg controller
*/
void dwc2_enable_global_interrupts(struct dwc2_hsotg *hsotg)
{
u32 ahbcfg = dwc2_readl(hsotg->regs + GAHBCFG);
ahbcfg |= GAHBCFG_GLBL_INTR_EN;
dwc2_writel(ahbcfg, hsotg->regs + GAHBCFG);
}
/**
* dwc2_disable_global_interrupts() - Disables the controller's Global
* Interrupt in the AHB Config register
*
* @hsotg: Programming view of DWC_otg controller
*/
void dwc2_disable_global_interrupts(struct dwc2_hsotg *hsotg)
{
u32 ahbcfg = dwc2_readl(hsotg->regs + GAHBCFG);
ahbcfg &= ~GAHBCFG_GLBL_INTR_EN;
dwc2_writel(ahbcfg, hsotg->regs + GAHBCFG);
}
/* Returns the controller's GHWCFG2.OTG_MODE. */
unsigned int dwc2_op_mode(struct dwc2_hsotg *hsotg)
{
u32 ghwcfg2 = dwc2_readl(hsotg->regs + GHWCFG2);
return (ghwcfg2 & GHWCFG2_OP_MODE_MASK) >>
GHWCFG2_OP_MODE_SHIFT;
}
/* Returns true if the controller is capable of DRD. */
bool dwc2_hw_is_otg(struct dwc2_hsotg *hsotg)
{
unsigned int op_mode = dwc2_op_mode(hsotg);
return (op_mode == GHWCFG2_OP_MODE_HNP_SRP_CAPABLE) ||
(op_mode == GHWCFG2_OP_MODE_SRP_ONLY_CAPABLE) ||
(op_mode == GHWCFG2_OP_MODE_NO_HNP_SRP_CAPABLE);
}
/* Returns true if the controller is host-only. */
bool dwc2_hw_is_host(struct dwc2_hsotg *hsotg)
{
unsigned int op_mode = dwc2_op_mode(hsotg);
return (op_mode == GHWCFG2_OP_MODE_SRP_CAPABLE_HOST) ||
(op_mode == GHWCFG2_OP_MODE_NO_SRP_CAPABLE_HOST);
}
/* Returns true if the controller is device-only. */
bool dwc2_hw_is_device(struct dwc2_hsotg *hsotg)
{
unsigned int op_mode = dwc2_op_mode(hsotg);
return (op_mode == GHWCFG2_OP_MODE_SRP_CAPABLE_DEVICE) ||
(op_mode == GHWCFG2_OP_MODE_NO_SRP_CAPABLE_DEVICE);
}
MODULE_DESCRIPTION("DESIGNWARE HS OTG Core");
MODULE_AUTHOR("Synopsys, Inc.");
MODULE_LICENSE("Dual BSD/GPL");