cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

core_intr.c (25221B)


      1// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
      2/*
      3 * core_intr.c - DesignWare HS OTG Controller common interrupt handling
      4 *
      5 * Copyright (C) 2004-2013 Synopsys, Inc.
      6 *
      7 * Redistribution and use in source and binary forms, with or without
      8 * modification, are permitted provided that the following conditions
      9 * are met:
     10 * 1. Redistributions of source code must retain the above copyright
     11 *    notice, this list of conditions, and the following disclaimer,
     12 *    without modification.
     13 * 2. Redistributions in binary form must reproduce the above copyright
     14 *    notice, this list of conditions and the following disclaimer in the
     15 *    documentation and/or other materials provided with the distribution.
     16 * 3. The names of the above-listed copyright holders may not be used
     17 *    to endorse or promote products derived from this software without
     18 *    specific prior written permission.
     19 *
     20 * ALTERNATIVELY, this software may be distributed under the terms of the
     21 * GNU General Public License ("GPL") as published by the Free Software
     22 * Foundation; either version 2 of the License, or (at your option) any
     23 * later version.
     24 *
     25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
     26 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     27 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
     29 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     30 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     32 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     33 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     34 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     36 */
     37
     38/*
     39 * This file contains the common interrupt handlers
     40 */
     41#include <linux/kernel.h>
     42#include <linux/module.h>
     43#include <linux/moduleparam.h>
     44#include <linux/spinlock.h>
     45#include <linux/interrupt.h>
     46#include <linux/dma-mapping.h>
     47#include <linux/io.h>
     48#include <linux/slab.h>
     49#include <linux/usb.h>
     50
     51#include <linux/usb/hcd.h>
     52#include <linux/usb/ch11.h>
     53
     54#include "core.h"
     55#include "hcd.h"
     56
     57static const char *dwc2_op_state_str(struct dwc2_hsotg *hsotg)
     58{
     59	switch (hsotg->op_state) {
     60	case OTG_STATE_A_HOST:
     61		return "a_host";
     62	case OTG_STATE_A_SUSPEND:
     63		return "a_suspend";
     64	case OTG_STATE_A_PERIPHERAL:
     65		return "a_peripheral";
     66	case OTG_STATE_B_PERIPHERAL:
     67		return "b_peripheral";
     68	case OTG_STATE_B_HOST:
     69		return "b_host";
     70	default:
     71		return "unknown";
     72	}
     73}
     74
     75/**
     76 * dwc2_handle_usb_port_intr - handles OTG PRTINT interrupts.
     77 * When the PRTINT interrupt fires, there are certain status bits in the Host
     78 * Port that needs to get cleared.
     79 *
     80 * @hsotg: Programming view of DWC_otg controller
     81 */
     82static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg)
     83{
     84	u32 hprt0 = dwc2_readl(hsotg, HPRT0);
     85
     86	if (hprt0 & HPRT0_ENACHG) {
     87		hprt0 &= ~HPRT0_ENA;
     88		dwc2_writel(hsotg, hprt0, HPRT0);
     89	}
     90}
     91
     92/**
     93 * dwc2_handle_mode_mismatch_intr() - Logs a mode mismatch warning message
     94 *
     95 * @hsotg: Programming view of DWC_otg controller
     96 */
     97static void dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg *hsotg)
     98{
     99	/* Clear interrupt */
    100	dwc2_writel(hsotg, GINTSTS_MODEMIS, GINTSTS);
    101
    102	dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n",
    103		 dwc2_is_host_mode(hsotg) ? "Host" : "Device");
    104}
    105
    106/**
    107 * dwc2_handle_otg_intr() - Handles the OTG Interrupts. It reads the OTG
    108 * Interrupt Register (GOTGINT) to determine what interrupt has occurred.
    109 *
    110 * @hsotg: Programming view of DWC_otg controller
    111 */
    112static void dwc2_handle_otg_intr(struct dwc2_hsotg *hsotg)
    113{
    114	u32 gotgint;
    115	u32 gotgctl;
    116	u32 gintmsk;
    117
    118	gotgint = dwc2_readl(hsotg, GOTGINT);
    119	gotgctl = dwc2_readl(hsotg, GOTGCTL);
    120	dev_dbg(hsotg->dev, "++OTG Interrupt gotgint=%0x [%s]\n", gotgint,
    121		dwc2_op_state_str(hsotg));
    122
    123	if (gotgint & GOTGINT_SES_END_DET) {
    124		dev_dbg(hsotg->dev,
    125			" ++OTG Interrupt: Session End Detected++ (%s)\n",
    126			dwc2_op_state_str(hsotg));
    127		gotgctl = dwc2_readl(hsotg, GOTGCTL);
    128
    129		if (dwc2_is_device_mode(hsotg))
    130			dwc2_hsotg_disconnect(hsotg);
    131
    132		if (hsotg->op_state == OTG_STATE_B_HOST) {
    133			hsotg->op_state = OTG_STATE_B_PERIPHERAL;
    134		} else {
    135			/*
    136			 * If not B_HOST and Device HNP still set, HNP did
    137			 * not succeed!
    138			 */
    139			if (gotgctl & GOTGCTL_DEVHNPEN) {
    140				dev_dbg(hsotg->dev, "Session End Detected\n");
    141				dev_err(hsotg->dev,
    142					"Device Not Connected/Responding!\n");
    143			}
    144
    145			/*
    146			 * If Session End Detected the B-Cable has been
    147			 * disconnected
    148			 */
    149			/* Reset to a clean state */
    150			hsotg->lx_state = DWC2_L0;
    151		}
    152
    153		gotgctl = dwc2_readl(hsotg, GOTGCTL);
    154		gotgctl &= ~GOTGCTL_DEVHNPEN;
    155		dwc2_writel(hsotg, gotgctl, GOTGCTL);
    156	}
    157
    158	if (gotgint & GOTGINT_SES_REQ_SUC_STS_CHNG) {
    159		dev_dbg(hsotg->dev,
    160			" ++OTG Interrupt: Session Request Success Status Change++\n");
    161		gotgctl = dwc2_readl(hsotg, GOTGCTL);
    162		if (gotgctl & GOTGCTL_SESREQSCS) {
    163			if (hsotg->params.phy_type == DWC2_PHY_TYPE_PARAM_FS &&
    164			    hsotg->params.i2c_enable) {
    165				hsotg->srp_success = 1;
    166			} else {
    167				/* Clear Session Request */
    168				gotgctl = dwc2_readl(hsotg, GOTGCTL);
    169				gotgctl &= ~GOTGCTL_SESREQ;
    170				dwc2_writel(hsotg, gotgctl, GOTGCTL);
    171			}
    172		}
    173	}
    174
    175	if (gotgint & GOTGINT_HST_NEG_SUC_STS_CHNG) {
    176		/*
    177		 * Print statements during the HNP interrupt handling
    178		 * can cause it to fail
    179		 */
    180		gotgctl = dwc2_readl(hsotg, GOTGCTL);
    181		/*
    182		 * WA for 3.00a- HW is not setting cur_mode, even sometimes
    183		 * this does not help
    184		 */
    185		if (hsotg->hw_params.snpsid >= DWC2_CORE_REV_3_00a)
    186			udelay(100);
    187		if (gotgctl & GOTGCTL_HSTNEGSCS) {
    188			if (dwc2_is_host_mode(hsotg)) {
    189				hsotg->op_state = OTG_STATE_B_HOST;
    190				/*
    191				 * Need to disable SOF interrupt immediately.
    192				 * When switching from device to host, the PCD
    193				 * interrupt handler won't handle the interrupt
    194				 * if host mode is already set. The HCD
    195				 * interrupt handler won't get called if the
    196				 * HCD state is HALT. This means that the
    197				 * interrupt does not get handled and Linux
    198				 * complains loudly.
    199				 */
    200				gintmsk = dwc2_readl(hsotg, GINTMSK);
    201				gintmsk &= ~GINTSTS_SOF;
    202				dwc2_writel(hsotg, gintmsk, GINTMSK);
    203
    204				/*
    205				 * Call callback function with spin lock
    206				 * released
    207				 */
    208				spin_unlock(&hsotg->lock);
    209
    210				/* Initialize the Core for Host mode */
    211				dwc2_hcd_start(hsotg);
    212				spin_lock(&hsotg->lock);
    213				hsotg->op_state = OTG_STATE_B_HOST;
    214			}
    215		} else {
    216			gotgctl = dwc2_readl(hsotg, GOTGCTL);
    217			gotgctl &= ~(GOTGCTL_HNPREQ | GOTGCTL_DEVHNPEN);
    218			dwc2_writel(hsotg, gotgctl, GOTGCTL);
    219			dev_dbg(hsotg->dev, "HNP Failed\n");
    220			dev_err(hsotg->dev,
    221				"Device Not Connected/Responding\n");
    222		}
    223	}
    224
    225	if (gotgint & GOTGINT_HST_NEG_DET) {
    226		/*
    227		 * The disconnect interrupt is set at the same time as
    228		 * Host Negotiation Detected. During the mode switch all
    229		 * interrupts are cleared so the disconnect interrupt
    230		 * handler will not get executed.
    231		 */
    232		dev_dbg(hsotg->dev,
    233			" ++OTG Interrupt: Host Negotiation Detected++ (%s)\n",
    234			(dwc2_is_host_mode(hsotg) ? "Host" : "Device"));
    235		if (dwc2_is_device_mode(hsotg)) {
    236			dev_dbg(hsotg->dev, "a_suspend->a_peripheral (%d)\n",
    237				hsotg->op_state);
    238			spin_unlock(&hsotg->lock);
    239			dwc2_hcd_disconnect(hsotg, false);
    240			spin_lock(&hsotg->lock);
    241			hsotg->op_state = OTG_STATE_A_PERIPHERAL;
    242		} else {
    243			/* Need to disable SOF interrupt immediately */
    244			gintmsk = dwc2_readl(hsotg, GINTMSK);
    245			gintmsk &= ~GINTSTS_SOF;
    246			dwc2_writel(hsotg, gintmsk, GINTMSK);
    247			spin_unlock(&hsotg->lock);
    248			dwc2_hcd_start(hsotg);
    249			spin_lock(&hsotg->lock);
    250			hsotg->op_state = OTG_STATE_A_HOST;
    251		}
    252	}
    253
    254	if (gotgint & GOTGINT_A_DEV_TOUT_CHG)
    255		dev_dbg(hsotg->dev,
    256			" ++OTG Interrupt: A-Device Timeout Change++\n");
    257	if (gotgint & GOTGINT_DBNCE_DONE)
    258		dev_dbg(hsotg->dev, " ++OTG Interrupt: Debounce Done++\n");
    259
    260	/* Clear GOTGINT */
    261	dwc2_writel(hsotg, gotgint, GOTGINT);
    262}
    263
    264/**
    265 * dwc2_handle_conn_id_status_change_intr() - Handles the Connector ID Status
    266 * Change Interrupt
    267 *
    268 * @hsotg: Programming view of DWC_otg controller
    269 *
    270 * Reads the OTG Interrupt Register (GOTCTL) to determine whether this is a
    271 * Device to Host Mode transition or a Host to Device Mode transition. This only
    272 * occurs when the cable is connected/removed from the PHY connector.
    273 */
    274static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg)
    275{
    276	u32 gintmsk;
    277
    278	/* Clear interrupt */
    279	dwc2_writel(hsotg, GINTSTS_CONIDSTSCHNG, GINTSTS);
    280
    281	/* Need to disable SOF interrupt immediately */
    282	gintmsk = dwc2_readl(hsotg, GINTMSK);
    283	gintmsk &= ~GINTSTS_SOF;
    284	dwc2_writel(hsotg, gintmsk, GINTMSK);
    285
    286	dev_dbg(hsotg->dev, " ++Connector ID Status Change Interrupt++  (%s)\n",
    287		dwc2_is_host_mode(hsotg) ? "Host" : "Device");
    288
    289	/*
    290	 * Need to schedule a work, as there are possible DELAY function calls.
    291	 */
    292	if (hsotg->wq_otg)
    293		queue_work(hsotg->wq_otg, &hsotg->wf_otg);
    294}
    295
    296/**
    297 * dwc2_handle_session_req_intr() - This interrupt indicates that a device is
    298 * initiating the Session Request Protocol to request the host to turn on bus
    299 * power so a new session can begin
    300 *
    301 * @hsotg: Programming view of DWC_otg controller
    302 *
    303 * This handler responds by turning on bus power. If the DWC_otg controller is
    304 * in low power mode, this handler brings the controller out of low power mode
    305 * before turning on bus power.
    306 */
    307static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg)
    308{
    309	int ret;
    310	u32 hprt0;
    311
    312	/* Clear interrupt */
    313	dwc2_writel(hsotg, GINTSTS_SESSREQINT, GINTSTS);
    314
    315	dev_dbg(hsotg->dev, "Session request interrupt - lx_state=%d\n",
    316		hsotg->lx_state);
    317
    318	if (dwc2_is_device_mode(hsotg)) {
    319		if (hsotg->lx_state == DWC2_L2) {
    320			if (hsotg->in_ppd) {
    321				ret = dwc2_exit_partial_power_down(hsotg, 0,
    322								   true);
    323				if (ret)
    324					dev_err(hsotg->dev,
    325						"exit power_down failed\n");
    326			}
    327
    328			/* Exit gadget mode clock gating. */
    329			if (hsotg->params.power_down ==
    330			    DWC2_POWER_DOWN_PARAM_NONE && hsotg->bus_suspended)
    331				dwc2_gadget_exit_clock_gating(hsotg, 0);
    332		}
    333
    334		/*
    335		 * Report disconnect if there is any previous session
    336		 * established
    337		 */
    338		dwc2_hsotg_disconnect(hsotg);
    339	} else {
    340		/* Turn on the port power bit. */
    341		hprt0 = dwc2_read_hprt0(hsotg);
    342		hprt0 |= HPRT0_PWR;
    343		dwc2_writel(hsotg, hprt0, HPRT0);
    344		/* Connect hcd after port power is set. */
    345		dwc2_hcd_connect(hsotg);
    346	}
    347}
    348
    349/**
    350 * dwc2_wakeup_from_lpm_l1 - Exit the device from LPM L1 state
    351 *
    352 * @hsotg: Programming view of DWC_otg controller
    353 *
    354 */
    355static void dwc2_wakeup_from_lpm_l1(struct dwc2_hsotg *hsotg)
    356{
    357	u32 glpmcfg;
    358	u32 i = 0;
    359
    360	if (hsotg->lx_state != DWC2_L1) {
    361		dev_err(hsotg->dev, "Core isn't in DWC2_L1 state\n");
    362		return;
    363	}
    364
    365	glpmcfg = dwc2_readl(hsotg, GLPMCFG);
    366	if (dwc2_is_device_mode(hsotg)) {
    367		dev_dbg(hsotg->dev, "Exit from L1 state\n");
    368		glpmcfg &= ~GLPMCFG_ENBLSLPM;
    369		glpmcfg &= ~GLPMCFG_HIRD_THRES_EN;
    370		dwc2_writel(hsotg, glpmcfg, GLPMCFG);
    371
    372		do {
    373			glpmcfg = dwc2_readl(hsotg, GLPMCFG);
    374
    375			if (!(glpmcfg & (GLPMCFG_COREL1RES_MASK |
    376					 GLPMCFG_L1RESUMEOK | GLPMCFG_SLPSTS)))
    377				break;
    378
    379			udelay(1);
    380		} while (++i < 200);
    381
    382		if (i == 200) {
    383			dev_err(hsotg->dev, "Failed to exit L1 sleep state in 200us.\n");
    384			return;
    385		}
    386		dwc2_gadget_init_lpm(hsotg);
    387	} else {
    388		/* TODO */
    389		dev_err(hsotg->dev, "Host side LPM is not supported.\n");
    390		return;
    391	}
    392
    393	/* Change to L0 state */
    394	hsotg->lx_state = DWC2_L0;
    395
    396	/* Inform gadget to exit from L1 */
    397	call_gadget(hsotg, resume);
    398}
    399
    400/*
    401 * This interrupt indicates that the DWC_otg controller has detected a
    402 * resume or remote wakeup sequence. If the DWC_otg controller is in
    403 * low power mode, the handler must brings the controller out of low
    404 * power mode. The controller automatically begins resume signaling.
    405 * The handler schedules a time to stop resume signaling.
    406 */
    407static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
    408{
    409	int ret;
    410
    411	/* Clear interrupt */
    412	dwc2_writel(hsotg, GINTSTS_WKUPINT, GINTSTS);
    413
    414	dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n");
    415	dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state);
    416
    417	if (hsotg->lx_state == DWC2_L1) {
    418		dwc2_wakeup_from_lpm_l1(hsotg);
    419		return;
    420	}
    421
    422	if (dwc2_is_device_mode(hsotg)) {
    423		dev_dbg(hsotg->dev, "DSTS=0x%0x\n",
    424			dwc2_readl(hsotg, DSTS));
    425		if (hsotg->lx_state == DWC2_L2) {
    426			if (hsotg->in_ppd) {
    427				u32 dctl = dwc2_readl(hsotg, DCTL);
    428				/* Clear Remote Wakeup Signaling */
    429				dctl &= ~DCTL_RMTWKUPSIG;
    430				dwc2_writel(hsotg, dctl, DCTL);
    431				ret = dwc2_exit_partial_power_down(hsotg, 1,
    432								   true);
    433				if (ret)
    434					dev_err(hsotg->dev,
    435						"exit partial_power_down failed\n");
    436				call_gadget(hsotg, resume);
    437			}
    438
    439			/* Exit gadget mode clock gating. */
    440			if (hsotg->params.power_down ==
    441			    DWC2_POWER_DOWN_PARAM_NONE && hsotg->bus_suspended)
    442				dwc2_gadget_exit_clock_gating(hsotg, 0);
    443		} else {
    444			/* Change to L0 state */
    445			hsotg->lx_state = DWC2_L0;
    446		}
    447	} else {
    448		if (hsotg->lx_state == DWC2_L2) {
    449			if (hsotg->in_ppd) {
    450				ret = dwc2_exit_partial_power_down(hsotg, 1,
    451								   true);
    452				if (ret)
    453					dev_err(hsotg->dev,
    454						"exit partial_power_down failed\n");
    455			}
    456
    457			if (hsotg->params.power_down ==
    458			    DWC2_POWER_DOWN_PARAM_NONE && hsotg->bus_suspended)
    459				dwc2_host_exit_clock_gating(hsotg, 1);
    460
    461			/*
    462			 * If we've got this quirk then the PHY is stuck upon
    463			 * wakeup.  Assert reset.  This will propagate out and
    464			 * eventually we'll re-enumerate the device.  Not great
    465			 * but the best we can do.  We can't call phy_reset()
    466			 * at interrupt time but there's no hurry, so we'll
    467			 * schedule it for later.
    468			 */
    469			if (hsotg->reset_phy_on_wake)
    470				dwc2_host_schedule_phy_reset(hsotg);
    471
    472			mod_timer(&hsotg->wkp_timer,
    473				  jiffies + msecs_to_jiffies(71));
    474		} else {
    475			/* Change to L0 state */
    476			hsotg->lx_state = DWC2_L0;
    477		}
    478	}
    479}
    480
    481/*
    482 * This interrupt indicates that a device has been disconnected from the
    483 * root port
    484 */
    485static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg)
    486{
    487	dwc2_writel(hsotg, GINTSTS_DISCONNINT, GINTSTS);
    488
    489	dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n",
    490		dwc2_is_host_mode(hsotg) ? "Host" : "Device",
    491		dwc2_op_state_str(hsotg));
    492
    493	if (hsotg->op_state == OTG_STATE_A_HOST)
    494		dwc2_hcd_disconnect(hsotg, false);
    495}
    496
    497/*
    498 * This interrupt indicates that SUSPEND state has been detected on the USB.
    499 *
    500 * For HNP the USB Suspend interrupt signals the change from "a_peripheral"
    501 * to "a_host".
    502 *
    503 * When power management is enabled the core will be put in low power mode.
    504 */
    505static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg)
    506{
    507	u32 dsts;
    508	int ret;
    509
    510	/* Clear interrupt */
    511	dwc2_writel(hsotg, GINTSTS_USBSUSP, GINTSTS);
    512
    513	dev_dbg(hsotg->dev, "USB SUSPEND\n");
    514
    515	if (dwc2_is_device_mode(hsotg)) {
    516		/*
    517		 * Check the Device status register to determine if the Suspend
    518		 * state is active
    519		 */
    520		dsts = dwc2_readl(hsotg, DSTS);
    521		dev_dbg(hsotg->dev, "%s: DSTS=0x%0x\n", __func__, dsts);
    522		dev_dbg(hsotg->dev,
    523			"DSTS.Suspend Status=%d HWCFG4.Power Optimize=%d HWCFG4.Hibernation=%d\n",
    524			!!(dsts & DSTS_SUSPSTS),
    525			hsotg->hw_params.power_optimized,
    526			hsotg->hw_params.hibernation);
    527
    528		/* Ignore suspend request before enumeration */
    529		if (!dwc2_is_device_connected(hsotg)) {
    530			dev_dbg(hsotg->dev,
    531				"ignore suspend request before enumeration\n");
    532			return;
    533		}
    534		if (dsts & DSTS_SUSPSTS) {
    535			switch (hsotg->params.power_down) {
    536			case DWC2_POWER_DOWN_PARAM_PARTIAL:
    537				ret = dwc2_enter_partial_power_down(hsotg);
    538				if (ret)
    539					dev_err(hsotg->dev,
    540						"enter partial_power_down failed\n");
    541
    542				udelay(100);
    543
    544				/* Ask phy to be suspended */
    545				if (!IS_ERR_OR_NULL(hsotg->uphy))
    546					usb_phy_set_suspend(hsotg->uphy, true);
    547				break;
    548			case DWC2_POWER_DOWN_PARAM_HIBERNATION:
    549				ret = dwc2_enter_hibernation(hsotg, 0);
    550				if (ret)
    551					dev_err(hsotg->dev,
    552						"enter hibernation failed\n");
    553				break;
    554			case DWC2_POWER_DOWN_PARAM_NONE:
    555				/*
    556				 * If neither hibernation nor partial power down are supported,
    557				 * clock gating is used to save power.
    558				 */
    559				if (!hsotg->params.no_clock_gating)
    560					dwc2_gadget_enter_clock_gating(hsotg);
    561			}
    562
    563			/*
    564			 * Change to L2 (suspend) state before releasing
    565			 * spinlock
    566			 */
    567			hsotg->lx_state = DWC2_L2;
    568
    569			/* Call gadget suspend callback */
    570			call_gadget(hsotg, suspend);
    571		}
    572	} else {
    573		if (hsotg->op_state == OTG_STATE_A_PERIPHERAL) {
    574			dev_dbg(hsotg->dev, "a_peripheral->a_host\n");
    575
    576			/* Change to L2 (suspend) state */
    577			hsotg->lx_state = DWC2_L2;
    578			/* Clear the a_peripheral flag, back to a_host */
    579			spin_unlock(&hsotg->lock);
    580			dwc2_hcd_start(hsotg);
    581			spin_lock(&hsotg->lock);
    582			hsotg->op_state = OTG_STATE_A_HOST;
    583		}
    584	}
    585}
    586
    587/**
    588 * dwc2_handle_lpm_intr - GINTSTS_LPMTRANRCVD Interrupt handler
    589 *
    590 * @hsotg: Programming view of DWC_otg controller
    591 *
    592 */
    593static void dwc2_handle_lpm_intr(struct dwc2_hsotg *hsotg)
    594{
    595	u32 glpmcfg;
    596	u32 pcgcctl;
    597	u32 hird;
    598	u32 hird_thres;
    599	u32 hird_thres_en;
    600	u32 enslpm;
    601
    602	/* Clear interrupt */
    603	dwc2_writel(hsotg, GINTSTS_LPMTRANRCVD, GINTSTS);
    604
    605	glpmcfg = dwc2_readl(hsotg, GLPMCFG);
    606
    607	if (!(glpmcfg & GLPMCFG_LPMCAP)) {
    608		dev_err(hsotg->dev, "Unexpected LPM interrupt\n");
    609		return;
    610	}
    611
    612	hird = (glpmcfg & GLPMCFG_HIRD_MASK) >> GLPMCFG_HIRD_SHIFT;
    613	hird_thres = (glpmcfg & GLPMCFG_HIRD_THRES_MASK &
    614			~GLPMCFG_HIRD_THRES_EN) >> GLPMCFG_HIRD_THRES_SHIFT;
    615	hird_thres_en = glpmcfg & GLPMCFG_HIRD_THRES_EN;
    616	enslpm = glpmcfg & GLPMCFG_ENBLSLPM;
    617
    618	if (dwc2_is_device_mode(hsotg)) {
    619		dev_dbg(hsotg->dev, "HIRD_THRES_EN = %d\n", hird_thres_en);
    620
    621		if (hird_thres_en && hird >= hird_thres) {
    622			dev_dbg(hsotg->dev, "L1 with utmi_l1_suspend_n\n");
    623		} else if (enslpm) {
    624			dev_dbg(hsotg->dev, "L1 with utmi_sleep_n\n");
    625		} else {
    626			dev_dbg(hsotg->dev, "Entering Sleep with L1 Gating\n");
    627
    628			pcgcctl = dwc2_readl(hsotg, PCGCTL);
    629			pcgcctl |= PCGCTL_ENBL_SLEEP_GATING;
    630			dwc2_writel(hsotg, pcgcctl, PCGCTL);
    631		}
    632		/**
    633		 * Examine prt_sleep_sts after TL1TokenTetry period max (10 us)
    634		 */
    635		udelay(10);
    636
    637		glpmcfg = dwc2_readl(hsotg, GLPMCFG);
    638
    639		if (glpmcfg & GLPMCFG_SLPSTS) {
    640			/* Save the current state */
    641			hsotg->lx_state = DWC2_L1;
    642			dev_dbg(hsotg->dev,
    643				"Core is in L1 sleep glpmcfg=%08x\n", glpmcfg);
    644
    645			/* Inform gadget that we are in L1 state */
    646			call_gadget(hsotg, suspend);
    647		}
    648	}
    649}
    650
    651#define GINTMSK_COMMON	(GINTSTS_WKUPINT | GINTSTS_SESSREQINT |		\
    652			 GINTSTS_CONIDSTSCHNG | GINTSTS_OTGINT |	\
    653			 GINTSTS_MODEMIS | GINTSTS_DISCONNINT |		\
    654			 GINTSTS_USBSUSP | GINTSTS_PRTINT |		\
    655			 GINTSTS_LPMTRANRCVD)
    656
    657/*
    658 * This function returns the Core Interrupt register
    659 */
    660static u32 dwc2_read_common_intr(struct dwc2_hsotg *hsotg)
    661{
    662	u32 gintsts;
    663	u32 gintmsk;
    664	u32 gahbcfg;
    665	u32 gintmsk_common = GINTMSK_COMMON;
    666
    667	gintsts = dwc2_readl(hsotg, GINTSTS);
    668	gintmsk = dwc2_readl(hsotg, GINTMSK);
    669	gahbcfg = dwc2_readl(hsotg, GAHBCFG);
    670
    671	/* If any common interrupts set */
    672	if (gintsts & gintmsk_common)
    673		dev_dbg(hsotg->dev, "gintsts=%08x  gintmsk=%08x\n",
    674			gintsts, gintmsk);
    675
    676	if (gahbcfg & GAHBCFG_GLBL_INTR_EN)
    677		return gintsts & gintmsk & gintmsk_common;
    678	else
    679		return 0;
    680}
    681
    682/**
    683 * dwc_handle_gpwrdn_disc_det() - Handles the gpwrdn disconnect detect.
    684 * Exits hibernation without restoring registers.
    685 *
    686 * @hsotg: Programming view of DWC_otg controller
    687 * @gpwrdn: GPWRDN register
    688 */
    689static inline void dwc_handle_gpwrdn_disc_det(struct dwc2_hsotg *hsotg,
    690					      u32 gpwrdn)
    691{
    692	u32 gpwrdn_tmp;
    693
    694	/* Switch-on voltage to the core */
    695	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
    696	gpwrdn_tmp &= ~GPWRDN_PWRDNSWTCH;
    697	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
    698	udelay(5);
    699
    700	/* Reset core */
    701	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
    702	gpwrdn_tmp &= ~GPWRDN_PWRDNRSTN;
    703	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
    704	udelay(5);
    705
    706	/* Disable Power Down Clamp */
    707	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
    708	gpwrdn_tmp &= ~GPWRDN_PWRDNCLMP;
    709	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
    710	udelay(5);
    711
    712	/* Deassert reset core */
    713	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
    714	gpwrdn_tmp |= GPWRDN_PWRDNRSTN;
    715	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
    716	udelay(5);
    717
    718	/* Disable PMU interrupt */
    719	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
    720	gpwrdn_tmp &= ~GPWRDN_PMUINTSEL;
    721	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
    722
    723	/* De-assert Wakeup Logic */
    724	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
    725	gpwrdn_tmp &= ~GPWRDN_PMUACTV;
    726	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
    727
    728	hsotg->hibernated = 0;
    729	hsotg->bus_suspended = 0;
    730
    731	if (gpwrdn & GPWRDN_IDSTS) {
    732		hsotg->op_state = OTG_STATE_B_PERIPHERAL;
    733		dwc2_core_init(hsotg, false);
    734		dwc2_enable_global_interrupts(hsotg);
    735		dwc2_hsotg_core_init_disconnected(hsotg, false);
    736		dwc2_hsotg_core_connect(hsotg);
    737	} else {
    738		hsotg->op_state = OTG_STATE_A_HOST;
    739
    740		/* Initialize the Core for Host mode */
    741		dwc2_core_init(hsotg, false);
    742		dwc2_enable_global_interrupts(hsotg);
    743		dwc2_hcd_start(hsotg);
    744	}
    745}
    746
    747/*
    748 * GPWRDN interrupt handler.
    749 *
    750 * The GPWRDN interrupts are those that occur in both Host and
    751 * Device mode while core is in hibernated state.
    752 */
    753static int dwc2_handle_gpwrdn_intr(struct dwc2_hsotg *hsotg)
    754{
    755	u32 gpwrdn;
    756	int linestate;
    757	int ret = 0;
    758
    759	gpwrdn = dwc2_readl(hsotg, GPWRDN);
    760	/* clear all interrupt */
    761	dwc2_writel(hsotg, gpwrdn, GPWRDN);
    762	linestate = (gpwrdn & GPWRDN_LINESTATE_MASK) >> GPWRDN_LINESTATE_SHIFT;
    763	dev_dbg(hsotg->dev,
    764		"%s: dwc2_handle_gpwrdwn_intr called gpwrdn= %08x\n", __func__,
    765		gpwrdn);
    766
    767	if ((gpwrdn & GPWRDN_DISCONN_DET) &&
    768	    (gpwrdn & GPWRDN_DISCONN_DET_MSK) && !linestate) {
    769		dev_dbg(hsotg->dev, "%s: GPWRDN_DISCONN_DET\n", __func__);
    770		/*
    771		 * Call disconnect detect function to exit from
    772		 * hibernation
    773		 */
    774		dwc_handle_gpwrdn_disc_det(hsotg, gpwrdn);
    775	} else if ((gpwrdn & GPWRDN_LNSTSCHG) &&
    776		   (gpwrdn & GPWRDN_LNSTSCHG_MSK) && linestate) {
    777		dev_dbg(hsotg->dev, "%s: GPWRDN_LNSTSCHG\n", __func__);
    778		if (hsotg->hw_params.hibernation &&
    779		    hsotg->hibernated) {
    780			if (gpwrdn & GPWRDN_IDSTS) {
    781				ret = dwc2_exit_hibernation(hsotg, 0, 0, 0);
    782				if (ret)
    783					dev_err(hsotg->dev,
    784						"exit hibernation failed.\n");
    785				call_gadget(hsotg, resume);
    786			} else {
    787				ret = dwc2_exit_hibernation(hsotg, 1, 0, 1);
    788				if (ret)
    789					dev_err(hsotg->dev,
    790						"exit hibernation failed.\n");
    791			}
    792		}
    793	} else if ((gpwrdn & GPWRDN_RST_DET) &&
    794		   (gpwrdn & GPWRDN_RST_DET_MSK)) {
    795		dev_dbg(hsotg->dev, "%s: GPWRDN_RST_DET\n", __func__);
    796		if (!linestate) {
    797			ret = dwc2_exit_hibernation(hsotg, 0, 1, 0);
    798			if (ret)
    799				dev_err(hsotg->dev,
    800					"exit hibernation failed.\n");
    801		}
    802	} else if ((gpwrdn & GPWRDN_STS_CHGINT) &&
    803		   (gpwrdn & GPWRDN_STS_CHGINT_MSK)) {
    804		dev_dbg(hsotg->dev, "%s: GPWRDN_STS_CHGINT\n", __func__);
    805		/*
    806		 * As GPWRDN_STS_CHGINT exit from hibernation flow is
    807		 * the same as in GPWRDN_DISCONN_DET flow. Call
    808		 * disconnect detect helper function to exit from
    809		 * hibernation.
    810		 */
    811		dwc_handle_gpwrdn_disc_det(hsotg, gpwrdn);
    812	}
    813
    814	return ret;
    815}
    816
    817/*
    818 * Common interrupt handler
    819 *
    820 * The common interrupts are those that occur in both Host and Device mode.
    821 * This handler handles the following interrupts:
    822 * - Mode Mismatch Interrupt
    823 * - OTG Interrupt
    824 * - Connector ID Status Change Interrupt
    825 * - Disconnect Interrupt
    826 * - Session Request Interrupt
    827 * - Resume / Remote Wakeup Detected Interrupt
    828 * - Suspend Interrupt
    829 */
    830irqreturn_t dwc2_handle_common_intr(int irq, void *dev)
    831{
    832	struct dwc2_hsotg *hsotg = dev;
    833	u32 gintsts;
    834	irqreturn_t retval = IRQ_NONE;
    835
    836	spin_lock(&hsotg->lock);
    837
    838	if (!dwc2_is_controller_alive(hsotg)) {
    839		dev_warn(hsotg->dev, "Controller is dead\n");
    840		goto out;
    841	}
    842
    843	/* Reading current frame number value in device or host modes. */
    844	if (dwc2_is_device_mode(hsotg))
    845		hsotg->frame_number = (dwc2_readl(hsotg, DSTS)
    846				       & DSTS_SOFFN_MASK) >> DSTS_SOFFN_SHIFT;
    847	else
    848		hsotg->frame_number = (dwc2_readl(hsotg, HFNUM)
    849				       & HFNUM_FRNUM_MASK) >> HFNUM_FRNUM_SHIFT;
    850
    851	gintsts = dwc2_read_common_intr(hsotg);
    852	if (gintsts & ~GINTSTS_PRTINT)
    853		retval = IRQ_HANDLED;
    854
    855	/* In case of hibernated state gintsts must not work */
    856	if (hsotg->hibernated) {
    857		dwc2_handle_gpwrdn_intr(hsotg);
    858		retval = IRQ_HANDLED;
    859		goto out;
    860	}
    861
    862	if (gintsts & GINTSTS_MODEMIS)
    863		dwc2_handle_mode_mismatch_intr(hsotg);
    864	if (gintsts & GINTSTS_OTGINT)
    865		dwc2_handle_otg_intr(hsotg);
    866	if (gintsts & GINTSTS_CONIDSTSCHNG)
    867		dwc2_handle_conn_id_status_change_intr(hsotg);
    868	if (gintsts & GINTSTS_DISCONNINT)
    869		dwc2_handle_disconnect_intr(hsotg);
    870	if (gintsts & GINTSTS_SESSREQINT)
    871		dwc2_handle_session_req_intr(hsotg);
    872	if (gintsts & GINTSTS_WKUPINT)
    873		dwc2_handle_wakeup_detected_intr(hsotg);
    874	if (gintsts & GINTSTS_USBSUSP)
    875		dwc2_handle_usb_suspend_intr(hsotg);
    876	if (gintsts & GINTSTS_LPMTRANRCVD)
    877		dwc2_handle_lpm_intr(hsotg);
    878
    879	if (gintsts & GINTSTS_PRTINT) {
    880		/*
    881		 * The port interrupt occurs while in device mode with HPRT0
    882		 * Port Enable/Disable
    883		 */
    884		if (dwc2_is_device_mode(hsotg)) {
    885			dev_dbg(hsotg->dev,
    886				" --Port interrupt received in Device mode--\n");
    887			dwc2_handle_usb_port_intr(hsotg);
    888			retval = IRQ_HANDLED;
    889		}
    890	}
    891
    892out:
    893	spin_unlock(&hsotg->lock);
    894	return retval;
    895}