From patchwork Wed Jun 28 19:12:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linus Walleij X-Patchwork-Id: 698573 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60DDDEB64DA for ; Wed, 28 Jun 2023 19:12:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230326AbjF1TMz (ORCPT ); Wed, 28 Jun 2023 15:12:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55994 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231509AbjF1TMy (ORCPT ); Wed, 28 Jun 2023 15:12:54 -0400 Received: from mail-lf1-x135.google.com (mail-lf1-x135.google.com [IPv6:2a00:1450:4864:20::135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B16351BD4 for ; Wed, 28 Jun 2023 12:12:52 -0700 (PDT) Received: by mail-lf1-x135.google.com with SMTP id 2adb3069b0e04-4f96d680399so8936601e87.0 for ; Wed, 28 Jun 2023 12:12:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1687979571; x=1690571571; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=loBTjqMQzL1qOkM4fTRAj5saj6jNoXL7fSZ6/KpKw/s=; b=um1qB32YpWtr+RfO3SmTUmqVpN2dw6Ml2eKQRlQtAz95z7bLxFKBS+5BFrQ4YB45KE PAnZ8kynAqfrvkZgAzeO6ub3QQxM/xx5P7o0dvzsRjNI+lUldLBR5LpmOeEBxTQIj+bV NME3x83pKxZamo/XV4feUD7Niz5Wpzk97rXb7JEhHz/oB/DqLPBWv/48fcuyDMNt1pDd ZfB0EkTLXHdESaGh0qRH3rGslAgZ6nW5V0PHl+CN9NH5Hli3/n/inbOe34JZzHgXt5+R ER2UMDCluuKmKfAD0vWX86p2ma8sCDx2N61lHe1GpRk5jxZQdyXZzbPKBNM25vDegp7h BQGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687979571; x=1690571571; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=loBTjqMQzL1qOkM4fTRAj5saj6jNoXL7fSZ6/KpKw/s=; b=X2REOr+tjUfDQkYaH7cXxgsrt1Bku/LJC49J+4MVvIcGO6H0o+8T994jLdznag4QK0 1NqNpWHD3tX4ZRUWMKfbMGYxSIHml8ssxQAkFgFIK6w+O0zY+NvaMqTTafHGyWj54gHD VikPtedVr044wu+Z2jr/KNoqsgrM5vlYJ52OTkOd0m18/+omZ4gAASdAXzWq7bi587VN 3owb9Bs4fHudZPYWEhoxGOU4NFX2oev+xHx3RH6RqZz9Sp9mr/j1ZtH2EAykqelO6iGi zK0AtU+Fd9DtIEP5K8SSUfLbUfhOMQ18kedhSiGbEa+WWk5bRGTjaF2HSaKDrQA7ezUf jRMw== X-Gm-Message-State: AC+VfDx/pdvjRhhRW3KsBY8TnDvRiJUfUweaFE78PO9FfB5xicOy2cvc hA1NH3sjH/jkeAIg5ypGqRISfL4y/R8Q90G2+kk= X-Google-Smtp-Source: ACHHUZ69Ai+7MyojdQtWcZuzs5axrPhCMssnMDvTiePKF39XhLLQDZaCiIq8rOAdUypP6yVcDVmvew== X-Received: by 2002:a05:6512:39d4:b0:4f9:607a:6504 with SMTP id k20-20020a05651239d400b004f9607a6504mr17192132lfu.29.1687979570877; Wed, 28 Jun 2023 12:12:50 -0700 (PDT) Received: from Fecusia.lan (c-05d8225c.014-348-6c756e10.bbcust.telenor.se. [92.34.216.5]) by smtp.gmail.com with ESMTPSA id w25-20020a19c519000000b004ec84d24818sm2031624lfe.282.2023.06.28.12.12.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Jun 2023 12:12:50 -0700 (PDT) From: Linus Walleij To: Ulf Hansson , linux-mmc@vger.kernel.org Cc: Russell King , Yann Gautier , Stefan Hansson , Maxime Coquelin , Alexandre Torgue , linux-stm32@st-md-mailman.stormreply.com, Linus Walleij Subject: [PATCH] mmc: mmci: Improve ux500 debug prints Date: Wed, 28 Jun 2023 21:12:43 +0200 Message-Id: <20230628191243.3632401-1-linus.walleij@linaro.org> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org To conclude the ux500 busy timeout fixes, this improves the debug and error prints so we can see a bit what is going on. Here is a typical dmesg with these new debug messages enabled: [ 2.648864] mmci-pl18x 80005000.mmc: mmc2: PL180 manf 80 rev4 at 0x80005000 irq 81,0 (pio) [ 2.662750] mmci-pl18x 80005000.mmc: DMA channels RX dma0chan4, TX dma0chan5 [ 3.480407] mmci-pl18x 80005000.mmc: no busy signalling in time CMD06 [ 3.487457] mmci-pl18x 80005000.mmc: no busy signalling in time CMD06 [ 3.998321] mmci-pl18x 80005000.mmc: timeout in state waiting for end IRQ waiting for busy CMD06 [ 3.998535] mmc2: new DDR MMC card at address 0001 [ 4.000030] mmcblk2: mmc2:0001 M4G1YC 3.69 GiB [ 4.008361] mmcblk2: p1 p2 p3 p4 p5 p6 p7 p8 p9 p10 p11 p12 p13 p14 p15 p16 p17 p18 p19 p20 p21 p22 p23 p24 p25 [ 4.017700] mmcblk2boot0: mmc2:0001 M4G1YC 2.00 MiB [ 4.020477] mmcblk2boot1: mmc2:0001 M4G1YC 2.00 MiB [ 4.022125] mmcblk2rpmb: mmc2:0001 M4G1YC 128 KiB, chardev (246:0) [ 5.791381] mmci-pl18x 80005000.mmc: no busy signalling in time CMD06 [ 10.938568] mmci-pl18x 80005000.mmc: timeout in state waiting for end IRQ waiting for busy CMD06 [ 17.982849] mmci-pl18x 80005000.mmc: lost busy status when waiting for busy start IRQ CMD06 [ 18.683563] mmci-pl18x 80005000.mmc: no busy signalling in time CMD06 [ 19.385437] mmci-pl18x 80005000.mmc: no busy signalling in time CMD06 [ 20.493652] mmci-pl18x 80005000.mmc: no busy signalling in time CMD06 We see a lot of lost IRQs and the timeout always occur while waiting for the end IRQ, and then the busy status is *low* meaning the busy indication is already de-asserted. So busy signalling is missed in various ways for various reasons, sometimes it appears that IRQs are simply lost. One hypothesis is that this happens because the events happen so fast that they are transient, and since the MMCI state machine in effect is handling an edge trigger (rising or falling signal on DAT0) the internal logic will miss the event, because the state machine in the hardware is sampling the line, and will at times detect only the first event but miss the second, fireing only one IRQ. We print the second timeout error with dev_err() since it is pretty serious, the other events are so common and simple to handle that we can keep them at dev_dbg() level. Signed-off-by: Linus Walleij --- drivers/mmc/host/mmci.c | 37 ++++++++++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 7 deletions(-) diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index 4fd28eaadc07..5d05269a8567 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -734,7 +734,8 @@ static bool ux500_busy_complete(struct mmci_host *host, struct mmc_command *cmd, } retries--; } - dev_dbg(mmc_dev(host->mmc), "no busy signalling in time\n"); + dev_dbg(mmc_dev(host->mmc), + "no busy signalling in time CMD%02x\n", cmd->opcode); ux500_busy_clear_mask_done(host); break; @@ -756,7 +757,8 @@ static bool ux500_busy_complete(struct mmci_host *host, struct mmc_command *cmd, host->busy_state = MMCI_BUSY_WAITING_FOR_END_IRQ; } else { dev_dbg(mmc_dev(host->mmc), - "lost busy status when waiting for busy start IRQ\n"); + "lost busy status when waiting for busy start IRQ CMD%02x\n", + cmd->opcode); cancel_delayed_work(&host->ux500_busy_timeout_work); ux500_busy_clear_mask_done(host); } @@ -770,13 +772,14 @@ static bool ux500_busy_complete(struct mmci_host *host, struct mmc_command *cmd, ux500_busy_clear_mask_done(host); } else { dev_dbg(mmc_dev(host->mmc), - "busy status still asserted when handling busy end IRQ - will keep waiting\n"); + "busy status still asserted when handling busy end IRQ - will keep waiting CMD%02x\n", + cmd->opcode); } break; default: - dev_dbg(mmc_dev(host->mmc), "fell through on state %d\n", - host->busy_state); + dev_sbg(mmc_dev(host->mmc), "fell through on state %d, CMD%02x\n", + host->busy_state, cmd->opcode); break; } @@ -1503,6 +1506,20 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd, } } +static char *ux500_state_str(struct mmci_host *host) +{ + switch (host->busy_state) { + case MMCI_BUSY_WAITING_FOR_START_IRQ: + return "waiting for start IRQ"; + case MMCI_BUSY_WAITING_FOR_END_IRQ: + return "waiting for end IRQ"; + case MMCI_BUSY_DONE: + return "not waiting for IRQs"; + default: + return "unknown"; + } +} + /* * This busy timeout worker is used to "kick" the command IRQ if a * busy detect IRQ fails to appear in reasonable time. Only used on @@ -1522,9 +1539,15 @@ static void ux500_busy_timeout_work(struct work_struct *work) /* If we are still busy, let's tag on timeout error. */ if (status & host->variant->busy_detect_flag) { status |= MCI_CMDTIMEOUT; - dev_dbg(mmc_dev(host->mmc), "timeout waiting for busy\n"); + dev_err(mmc_dev(host->mmc), + "timeout in state %s still busy with CMD%02x\n", + ux500_state_str(host), + host->cmd->opcode); } else { - dev_dbg(mmc_dev(host->mmc), "timeout waiting for busy IRQ\n"); + dev_err(mmc_dev(host->mmc), + "timeout in state %s waiting for busy CMD%02x\n", + ux500_state_str(host), + host->cmd->opcode); } mmci_cmd_irq(host, host->cmd, status);