From patchwork Sat Dec 5 13:55:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 11953407 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.2 required=3.0 tests=BAYES_00,DATE_IN_PAST_03_06, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D10AC433FE for ; Sat, 5 Dec 2020 18:54:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C147C2310B for ; Sat, 5 Dec 2020 18:54:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726043AbgLESyh (ORCPT ); Sat, 5 Dec 2020 13:54:37 -0500 Received: from ns2.baikalchip.ru ([94.125.187.42]:53406 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725372AbgLESyh (ORCPT ); Sat, 5 Dec 2020 13:54:37 -0500 From: Serge Semin To: Felipe Balbi , John Youn , Greg Kroah-Hartman , Felipe Balbi , David Cohen , Heikki Krogerus CC: Serge Semin , Serge Semin , Alexey Malahov , Pavel Parkhomenko , , , Felipe Balbi Subject: [PATCH v4 1/3] usb: dwc3: ulpi: Use VStsDone to detect PHY regs access completion Date: Sat, 5 Dec 2020 16:55:19 +0300 Message-ID: <20201205135521.28344-2-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20201205135521.28344-1-Sergey.Semin@baikalelectronics.ru> References: <20201205135521.28344-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org In accordance with [1] the DWC_usb3 core sets the GUSB2PHYACCn.VStsDone bit when the PHY vendor control access is done and clears it when the application initiates a new transaction. The doc doesn't say anything about the GUSB2PHYACCn.VStsBsy flag serving for the same purpose. Moreover we've discovered that the VStsBsy flag can be cleared before the VStsDone bit. So using the former as a signal of the PHY control registers completion might be dangerous. Let's have the VStsDone flag utilized instead then. [1] Synopsys DesignWare Cores SuperSpeed USB 3.0 xHCI Host Controller Databook, 2.70a, December 2013, p.388 Fixes: 88bc9d194ff6 ("usb: dwc3: add ULPI interface support") Signed-off-by: Serge Semin Acked-by: Heikki Krogerus --- Changelog v3: - Add Fixes tag to the commit log. --- drivers/usb/dwc3/core.h | 1 + drivers/usb/dwc3/ulpi.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 2f95f08ca511..1b241f937d8f 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -285,6 +285,7 @@ /* Global USB2 PHY Vendor Control Register */ #define DWC3_GUSB2PHYACC_NEWREGREQ BIT(25) +#define DWC3_GUSB2PHYACC_DONE BIT(24) #define DWC3_GUSB2PHYACC_BUSY BIT(23) #define DWC3_GUSB2PHYACC_WRITE BIT(22) #define DWC3_GUSB2PHYACC_ADDR(n) (n << 16) diff --git a/drivers/usb/dwc3/ulpi.c b/drivers/usb/dwc3/ulpi.c index aa213c9815f6..3cc4f4970c05 100644 --- a/drivers/usb/dwc3/ulpi.c +++ b/drivers/usb/dwc3/ulpi.c @@ -24,7 +24,7 @@ static int dwc3_ulpi_busyloop(struct dwc3 *dwc) while (count--) { reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYACC(0)); - if (!(reg & DWC3_GUSB2PHYACC_BUSY)) + if (reg & DWC3_GUSB2PHYACC_DONE) return 0; cpu_relax(); } From patchwork Sat Dec 5 13:55:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 11953363 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.2 required=3.0 tests=BAYES_00,DATE_IN_PAST_03_06, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA54FC18E57 for ; Sat, 5 Dec 2020 18:40:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B084A22E00 for ; Sat, 5 Dec 2020 18:40:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728879AbgLESTY (ORCPT ); Sat, 5 Dec 2020 13:19:24 -0500 Received: from mx.chip.baikal.ru ([94.125.187.42]:53292 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727571AbgLERmg (ORCPT ); Sat, 5 Dec 2020 12:42:36 -0500 From: Serge Semin To: Felipe Balbi , John Youn , Greg Kroah-Hartman , Felipe Balbi , David Cohen , Heikki Krogerus CC: Serge Semin , Serge Semin , Alexey Malahov , Pavel Parkhomenko , , , Felipe Balbi Subject: [PATCH v4 2/3] usb: dwc3: ulpi: Replace CPU-based busyloop with Protocol-based one Date: Sat, 5 Dec 2020 16:55:20 +0300 Message-ID: <20201205135521.28344-3-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20201205135521.28344-1-Sergey.Semin@baikalelectronics.ru> References: <20201205135521.28344-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Originally the procedure of the ULPI transaction finish detection has been developed as a simple busy-loop with just decrementing counter and no delays. It's wrong since on different systems the loop will take a different time to complete. So if the system bus and CPU are fast enough to overtake the ULPI bus and the companion PHY reaction, then we'll get to take a false timeout error. Fix this by converting the busy-loop procedure to take the standard bus speed, address value and the registers access mode into account for the busy-loop delay calculation. Here is the way the fix works. It's known that the ULPI bus is clocked with 60MHz signal. In accordance with [1] the ULPI bus protocol is created so to spend 5 and 6 clock periods for immediate register write and read operations respectively, and 6 and 7 clock periods - for the extended register writes and reads. Based on that we can easily pre-calculate the time which will be needed for the controller to perform a requested IO operation. Note we'll still preserve the attempts counter in case if the DWC USB3 controller has got some internals delays. [1] UTMI+ Low Pin Interface (ULPI) Specification, Revision 1.1, October 20, 2004, pp. 30 - 36. Fixes: 88bc9d194ff6 ("usb: dwc3: add ULPI interface support") Signed-off-by: Serge Semin Acked-by: Heikki Krogerus --- drivers/usb/dwc3/ulpi.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/usb/dwc3/ulpi.c b/drivers/usb/dwc3/ulpi.c index 3cc4f4970c05..54c877f7b51d 100644 --- a/drivers/usb/dwc3/ulpi.c +++ b/drivers/usb/dwc3/ulpi.c @@ -7,6 +7,8 @@ * Author: Heikki Krogerus */ +#include +#include #include #include "core.h" @@ -17,12 +19,22 @@ DWC3_GUSB2PHYACC_ADDR(ULPI_ACCESS_EXTENDED) | \ DWC3_GUSB2PHYACC_EXTEND_ADDR(a) : DWC3_GUSB2PHYACC_ADDR(a)) -static int dwc3_ulpi_busyloop(struct dwc3 *dwc) +#define DWC3_ULPI_BASE_DELAY DIV_ROUND_UP(NSEC_PER_SEC, 60000000L) + +static int dwc3_ulpi_busyloop(struct dwc3 *dwc, u8 addr, bool read) { + unsigned long ns = 5L * DWC3_ULPI_BASE_DELAY; unsigned int count = 1000; u32 reg; + if (addr >= ULPI_EXT_VENDOR_SPECIFIC) + ns += DWC3_ULPI_BASE_DELAY; + + if (read) + ns += DWC3_ULPI_BASE_DELAY; + while (count--) { + ndelay(ns); reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYACC(0)); if (reg & DWC3_GUSB2PHYACC_DONE) return 0; @@ -47,7 +59,7 @@ static int dwc3_ulpi_read(struct device *dev, u8 addr) reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr); dwc3_writel(dwc->regs, DWC3_GUSB2PHYACC(0), reg); - ret = dwc3_ulpi_busyloop(dwc); + ret = dwc3_ulpi_busyloop(dwc, addr, true); if (ret) return ret; @@ -71,7 +83,7 @@ static int dwc3_ulpi_write(struct device *dev, u8 addr, u8 val) reg |= DWC3_GUSB2PHYACC_WRITE | val; dwc3_writel(dwc->regs, DWC3_GUSB2PHYACC(0), reg); - return dwc3_ulpi_busyloop(dwc); + return dwc3_ulpi_busyloop(dwc, addr, false); } static const struct ulpi_ops dwc3_ulpi_ops = { From patchwork Sat Dec 5 13:55:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 11953361 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.2 required=3.0 tests=BAYES_00,DATE_IN_PAST_03_06, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 21FF0C1B0D8 for ; Sat, 5 Dec 2020 18:40:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F0CCC230FD for ; Sat, 5 Dec 2020 18:40:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728898AbgLESTY (ORCPT ); Sat, 5 Dec 2020 13:19:24 -0500 Received: from mx.baikalchip.com ([94.125.187.42]:53294 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727530AbgLERmh (ORCPT ); Sat, 5 Dec 2020 12:42:37 -0500 From: Serge Semin To: Felipe Balbi , John Youn , Greg Kroah-Hartman , Felipe Balbi , David Cohen , Heikki Krogerus CC: Serge Semin , Serge Semin , Alexey Malahov , Pavel Parkhomenko , , Subject: [PATCH v4 3/3] usb: dwc3: ulpi: Fix USB2.0 HS/FS/LS PHY suspend regression Date: Sat, 5 Dec 2020 16:55:21 +0300 Message-ID: <20201205135521.28344-4-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20201205135521.28344-1-Sergey.Semin@baikalelectronics.ru> References: <20201205135521.28344-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org First of all the commit e0082698b689 ("usb: dwc3: ulpi: conditionally resume ULPI PHY") introduced the Suspend USB2.0 HS/FS/LS PHY regression, as by design of the fix any attempt to read/write from/to the PHY control registers will completely disable the PHY suspension, which consequently will increase the USB bus power consumption. Secondly the fix won't work well for the very first attempt of the ULPI PHY control registers IO, because after disabling the USB2.0 PHY suspension functionality it will still take some time for the bus to resume from the sleep state if one has been reached before it. So the very first PHY register read/write operation will take more time than the busy-loop provides and the IO timeout error might be returned anyway. Here we suggest to fix the denoted problems in the following way. First of all let's not disable the Suspend USB2.0 HS/FS/LS PHY functionality so to make the controller and the USB2.0 bus more power efficient. Secondly instead of that we'll extend the PHY IO op wait procedure with 1 - 1.2 ms sleep if the PHY suspension is enabled (1ms should be enough as by LPM specification it is at most how long it takes for the USB2.0 bus to resume from L1 (Sleep) state). Finally in case if the USB2.0 PHY suspension functionality has been disabled on the DWC USB3 controller setup procedure we'll compensate the USB bus resume process latency by extending the busy-loop attempts counter. Fixes: e0082698b689 ("usb: dwc3: ulpi: conditionally resume ULPI PHY") Signed-off-by: Serge Semin Acked-by: Heikki Krogerus --- drivers/usb/dwc3/ulpi.c | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-) diff --git a/drivers/usb/dwc3/ulpi.c b/drivers/usb/dwc3/ulpi.c index 54c877f7b51d..f23f4c9a557e 100644 --- a/drivers/usb/dwc3/ulpi.c +++ b/drivers/usb/dwc3/ulpi.c @@ -24,7 +24,7 @@ static int dwc3_ulpi_busyloop(struct dwc3 *dwc, u8 addr, bool read) { unsigned long ns = 5L * DWC3_ULPI_BASE_DELAY; - unsigned int count = 1000; + unsigned int count = 10000; u32 reg; if (addr >= ULPI_EXT_VENDOR_SPECIFIC) @@ -33,6 +33,10 @@ static int dwc3_ulpi_busyloop(struct dwc3 *dwc, u8 addr, bool read) if (read) ns += DWC3_ULPI_BASE_DELAY; + reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0)); + if (reg & DWC3_GUSB2PHYCFG_SUSPHY) + usleep_range(1000, 1200); + while (count--) { ndelay(ns); reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYACC(0)); @@ -50,12 +54,6 @@ static int dwc3_ulpi_read(struct device *dev, u8 addr) u32 reg; int ret; - reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0)); - if (reg & DWC3_GUSB2PHYCFG_SUSPHY) { - reg &= ~DWC3_GUSB2PHYCFG_SUSPHY; - dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg); - } - reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr); dwc3_writel(dwc->regs, DWC3_GUSB2PHYACC(0), reg); @@ -73,12 +71,6 @@ static int dwc3_ulpi_write(struct device *dev, u8 addr, u8 val) struct dwc3 *dwc = dev_get_drvdata(dev); u32 reg; - reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0)); - if (reg & DWC3_GUSB2PHYCFG_SUSPHY) { - reg &= ~DWC3_GUSB2PHYCFG_SUSPHY; - dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg); - } - reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr); reg |= DWC3_GUSB2PHYACC_WRITE | val; dwc3_writel(dwc->regs, DWC3_GUSB2PHYACC(0), reg);