Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752778AbdLHIa1 (ORCPT ); Fri, 8 Dec 2017 03:30:27 -0500 Received: from us01smtprelay-2.synopsys.com ([198.182.60.111]:40656 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751253AbdLHIaZ (ORCPT ); Fri, 8 Dec 2017 03:30:25 -0500 Date: Fri, 8 Dec 2017 12:30:19 +0400 From: Minas Harutyunyan Subject: [PATCH v2] usb: dwc2: Change TxFIFO and RxFIFO flushing flow To: John Youn , Felipe Balbi , "Greg Kroah-Hartman" , , CC: Minas Harutyunyan MIME-Version: 1.0 Content-Type: text/plain Message-ID: <4aba4460-4e5e-4a84-ba2f-42be703e2c3e@US01WEHTC1.internal.synopsys.com> X-Originating-IP: [10.13.184.19] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1697 Lines: 62 Before flushing fifos required to check AHB master state and flush when AHB master is in IDLE state. Signed-off-by: Minas Harutyunyan --- drivers/usb/dwc2/core.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c index dbca3b8890da..4d2a8c452e6b 100644 --- a/drivers/usb/dwc2/core.c +++ b/drivers/usb/dwc2/core.c @@ -670,10 +670,23 @@ void dwc2_flush_tx_fifo(struct dwc2_hsotg *hsotg, const int num) dev_vdbg(hsotg->dev, "Flush Tx FIFO %d\n", num); + /* Wait for AHB master IDLE state */ + do { + greset = dwc2_readl(hsotg->regs + GRSTCTL); + if (++count > 10000) { + dev_warn(hsotg->dev, + "%s() HANG! AHB Idle GRSTCTL=%0x\n", + __func__, greset); + return; + } + udelay(1); + } while (!(greset & GRSTCTL_AHBIDLE)); + greset = GRSTCTL_TXFFLSH; greset |= num << GRSTCTL_TXFNUM_SHIFT & GRSTCTL_TXFNUM_MASK; dwc2_writel(greset, hsotg->regs + GRSTCTL); + count = 0; do { greset = dwc2_readl(hsotg->regs + GRSTCTL); if (++count > 10000) { @@ -702,9 +715,23 @@ void dwc2_flush_rx_fifo(struct dwc2_hsotg *hsotg) dev_vdbg(hsotg->dev, "%s()\n", __func__); + /* Wait for AHB master IDLE state */ + do { + greset = dwc2_readl(hsotg->regs + GRSTCTL); + if (++count > 10000) { + dev_warn(hsotg->dev, + "%s() HANG! AHB Idle GRSTCTL=%0x\n", + __func__, greset); + return; + } + udelay(1); + } while (!(greset & GRSTCTL_AHBIDLE)); + greset = GRSTCTL_RXFFLSH; dwc2_writel(greset, hsotg->regs + GRSTCTL); + /* Wait for RxFIFO flush done */ + count = 0; do { greset = dwc2_readl(hsotg->regs + GRSTCTL); if (++count > 10000) { -- 2.11.0