From patchwork Tue Dec 4 07:24:28 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chunyan Zhang X-Patchwork-Id: 10711185 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C5B301057 for ; Tue, 4 Dec 2018 07:25:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AF5032B072 for ; Tue, 4 Dec 2018 07:25:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A3AAB2B135; Tue, 4 Dec 2018 07:25:07 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E10712B072 for ; Tue, 4 Dec 2018 07:25:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726070AbeLDHYo (ORCPT ); Tue, 4 Dec 2018 02:24:44 -0500 Received: from mail-pf1-f193.google.com ([209.85.210.193]:37276 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726065AbeLDHYo (ORCPT ); Tue, 4 Dec 2018 02:24:44 -0500 Received: by mail-pf1-f193.google.com with SMTP id y126so7772440pfb.4 for ; Mon, 03 Dec 2018 23:24:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=j1zCZgXi/XKYT/+/SSecVSrn6u7kBTAh7f/boLUDo0A=; b=CFVAQcwzpaTCHZBZsPWE7RvrrZIM+csPWponA4Icm7Cm0/C0JWTl8PtFS5h+RRXgim /8e+BtjezhNyVExGtt/nxRE6DGYLcFmT3Y0P+27grEZ1CL4hN1c8TLQlGLyAt1h+p25/ 0/pXjtDa8ZpPHbiq+D1tj3Pc/jtCvcr9n1YBg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=j1zCZgXi/XKYT/+/SSecVSrn6u7kBTAh7f/boLUDo0A=; b=aFm2WRlmisXLDihBpyqG5N1Eks2qqZ7xcOnTIOyi7DXZeqUqVxOZm18y+OkBxRJvl8 RyrYk0NjHGwM4+i71GHMGA+o+Zqo3GDD3jalXJHuekty0QkF51r3jVg68gGMSJBhWGsg 4quAsZLfbxAJOEHb5lxmWQEosV25g69G9Cqvw3fUf2bOD1ohCxu9M5Pgj1hoNY5OzLtx 6mBOdr1CF6o6CXxpUNHwkoj5YQ8/aP/aKdQuCaaopbsbinAjN5SYxd3d77vNjJUlcJUS AuiTccTWWR5fBulItPudu3lFVMhrTMBJbnUsamv1BOIk+4DBvH1OlYKHVyLW4+tOz9u3 HIeQ== X-Gm-Message-State: AA+aEWbTDG24HhIAF7YWL+IdHm4NXXOSAa7Jn6k8kZxJ2cmD2HTO/pwC yCuBE7he4EPqbwWRtQbd5gFlxg== X-Google-Smtp-Source: AFSGD/UTlRcgNrFR7RYtfOpzItAUr34fk0NjOIsWz1i200ISX26LONyh9PSmVF9DFktNUn/cCUKyGA== X-Received: by 2002:a63:295:: with SMTP id 143mr15410585pgc.362.1543908283125; Mon, 03 Dec 2018 23:24:43 -0800 (PST) Received: from ubt.spreadtrum.com ([117.18.48.82]) by smtp.gmail.com with ESMTPSA id g136sm22705943pfb.154.2018.12.03.23.24.39 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 03 Dec 2018 23:24:42 -0800 (PST) From: Chunyan Zhang To: Ulf Hansson , Adrian Hunter , Faiz Abbas Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Arnd Bergmann , Mark Brown , Kishon Vijay Abraham I , Sekhar Nori , Chunyan Zhang Subject: [PATCH V3 1/3] mmc: sdhci: add support for using external DMA devices Date: Tue, 4 Dec 2018 15:24:28 +0800 Message-Id: <1543908270-13953-2-git-send-email-zhang.chunyan@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1543908270-13953-1-git-send-email-zhang.chunyan@linaro.org> References: <1543908270-13953-1-git-send-email-zhang.chunyan@linaro.org> Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Some standard SD host controllers can support both external dma controllers as well as ADMA/SDMA in which the SD host controller acts as DMA master. TI's omap controller is the case as an example. Currently the generic SDHCI code supports ADMA/SDMA integrated in the host controller but does not have any support for external DMA controllers implemented using dmaengine, meaning that custom code is needed for any systems that use an external DMA controller with SDHCI. Signed-off-by: Chunyan Zhang --- drivers/mmc/host/Kconfig | 3 + drivers/mmc/host/sdhci.c | 185 ++++++++++++++++++++++++++++++++++++++++++++++- drivers/mmc/host/sdhci.h | 8 ++ 3 files changed, 195 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index 1b58739..3101da6 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig @@ -977,3 +977,6 @@ config MMC_SDHCI_OMAP If you have a controller with this interface, say Y or M here. If unsure, say N. + +config MMC_SDHCI_EXTERNAL_DMA + bool diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 99bdae5..04b029c 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -14,6 +14,7 @@ */ #include +#include #include #include #include @@ -1309,6 +1310,162 @@ static void sdhci_del_timer(struct sdhci_host *host, struct mmc_request *mrq) del_timer(&host->timer); } +#if IS_ENABLED(CONFIG_MMC_SDHCI_EXTERNAL_DMA) +static int sdhci_external_dma_init(struct sdhci_host *host) +{ + int ret = 0; + struct mmc_host *mmc = host->mmc; + + host->tx_chan = dma_request_chan(mmc->parent, "tx"); + if (IS_ERR(host->tx_chan)) { + ret = PTR_ERR(host->tx_chan); + if (ret != -EPROBE_DEFER) + pr_warn("Failed to request TX DMA channel.\n"); + host->tx_chan = NULL; + return ret; + } + + host->rx_chan = dma_request_chan(mmc->parent, "rx"); + if (IS_ERR(host->rx_chan)) { + if (host->tx_chan) { + dma_release_channel(host->tx_chan); + host->tx_chan = NULL; + } + + ret = PTR_ERR(host->rx_chan); + if (ret != -EPROBE_DEFER) + pr_warn("Failed to request RX DMA channel.\n"); + host->rx_chan = NULL; + } + + return ret; +} + +static inline struct dma_chan * +sdhci_external_dma_channel(struct sdhci_host *host, struct mmc_data *data) +{ + return data->flags & MMC_DATA_WRITE ? host->tx_chan : host->rx_chan; +} + +static int sdhci_external_dma_setup(struct sdhci_host *host, + struct mmc_command *cmd) +{ + int ret, i; + struct dma_async_tx_descriptor *desc; + struct mmc_data *data = cmd->data; + struct dma_chan *chan; + struct dma_slave_config cfg; + dma_cookie_t cookie; + + if (!data) + return 0; + + if (!host->mapbase) + return -EINVAL; + + cfg.src_addr = host->mapbase + SDHCI_BUFFER; + cfg.dst_addr = host->mapbase + SDHCI_BUFFER; + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + cfg.src_maxburst = data->blksz / 4; + cfg.dst_maxburst = data->blksz / 4; + + /* Sanity check: all the SG entries must be aligned by block size. */ + for (i = 0; i < data->sg_len; i++) { + if ((data->sg + i)->length % data->blksz) + return -EINVAL; + } + + chan = sdhci_external_dma_channel(host, data); + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) + return ret; + + desc = dmaengine_prep_slave_sg(chan, data->sg, data->sg_len, + mmc_get_dma_dir(data), + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) + return -EINVAL; + + desc->callback = NULL; + desc->callback_param = NULL; + + cookie = dmaengine_submit(desc); + if (cookie < 0) + ret = cookie; + + return ret; +} + +static void sdhci_external_dma_release(struct sdhci_host *host) +{ + if (host->tx_chan) { + dma_release_channel(host->tx_chan); + host->tx_chan = NULL; + } + + if (host->rx_chan) { + dma_release_channel(host->rx_chan); + host->rx_chan = NULL; + } + + sdhci_switch_external_dma(host, false); +} + +static void sdhci_external_dma_prepare_data(struct sdhci_host *host, + struct mmc_command *cmd) +{ + if (sdhci_external_dma_setup(host, cmd)) { + sdhci_external_dma_release(host); + pr_err("%s: Failed to setup external DMA, switch to the DMA/PIO which standard SDHCI provides.\n", + mmc_hostname(host->mmc)); + } else { + /* Prepare for using external dma */ + host->flags |= SDHCI_REQ_USE_DMA; + } + + sdhci_prepare_data(host, cmd); +} + +static void sdhci_external_dma_pre_transfer(struct sdhci_host *host, + struct mmc_command *cmd) +{ + struct dma_chan *chan; + + if (cmd->data) { + sdhci_set_timeout(host, cmd); + chan = sdhci_external_dma_channel(host, cmd->data); + dma_async_issue_pending(chan); + } +} +#else +static int sdhci_external_dma_init(struct sdhci_host *host) +{ + return -EOPNOTSUPP; +} + +static void sdhci_external_dma_release(struct sdhci_host *host) +{} + +static void sdhci_external_dma_prepare_data(struct sdhci_host *host, + struct mmc_command *cmd) +{ + /* If MMC_SDHCI_EXTERNAL_DMA not supported, PIO will be used */ + sdhci_prepare_data(host, cmd); +} + +static void sdhci_external_dma_pre_transfer(struct sdhci_host *host, + struct mmc_command *cmd) +{} +#endif + +void sdhci_switch_external_dma(struct sdhci_host *host, bool en) +{ + host->use_external_dma = en; +} +EXPORT_SYMBOL_GPL(sdhci_switch_external_dma); + void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd) { int flags; @@ -1355,7 +1512,10 @@ void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd) host->data_cmd = cmd; } - sdhci_prepare_data(host, cmd); + if (host->use_external_dma) + sdhci_external_dma_prepare_data(host, cmd); + else + sdhci_prepare_data(host, cmd); sdhci_writel(host, cmd->arg, SDHCI_ARGUMENT); @@ -1397,6 +1557,9 @@ void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd) timeout += 10 * HZ; sdhci_mod_timer(host, cmd->mrq, timeout); + if (host->use_external_dma) + sdhci_external_dma_pre_transfer(host, cmd); + sdhci_writew(host, SDHCI_MAKE_CMD(cmd->opcode, flags), SDHCI_COMMAND); } EXPORT_SYMBOL_GPL(sdhci_send_command); @@ -4133,6 +4296,19 @@ int sdhci_setup_host(struct sdhci_host *host) return ret; } + if (host->use_external_dma) { + ret = sdhci_external_dma_init(host); + if (ret == -EPROBE_DEFER) + goto unreg; + + /* + * Fall back to use the DMA/PIO integrated in standard SDHCI + * instead of external DMA devices. + */ + if (ret) + sdhci_switch_external_dma(host, false); + } + return 0; unreg: @@ -4161,6 +4337,10 @@ void sdhci_cleanup_host(struct sdhci_host *host) dma_free_coherent(mmc_dev(mmc), host->align_buffer_sz + host->adma_table_sz, host->align_buffer, host->align_addr); + + if (host->use_external_dma) + sdhci_external_dma_release(host); + host->adma_table = NULL; host->align_buffer = NULL; } @@ -4295,6 +4475,9 @@ void sdhci_remove_host(struct sdhci_host *host, int dead) host->adma_table_sz, host->align_buffer, host->align_addr); + if (host->use_external_dma) + sdhci_external_dma_release(host); + host->adma_table = NULL; host->align_buffer = NULL; } diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index b001cf4..8e50a97 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -475,6 +475,7 @@ struct sdhci_host { int irq; /* Device IRQ */ void __iomem *ioaddr; /* Mapped address */ + phys_addr_t mapbase; /* physical address base */ char *bounce_buffer; /* For packing SDMA reads/writes */ dma_addr_t bounce_addr; unsigned int bounce_buffer_size; @@ -524,6 +525,7 @@ struct sdhci_host { bool pending_reset; /* Cmd/data reset is pending */ bool irq_wake_enabled; /* IRQ wakeup is enabled */ bool v4_mode; /* Host Version 4 Enable */ + bool use_external_dma; struct mmc_request *mrqs_done[SDHCI_MAX_MRQS]; /* Requests done */ struct mmc_command *cmd; /* Current command */ @@ -552,6 +554,11 @@ struct sdhci_host { struct timer_list timer; /* Timer for timeouts */ struct timer_list data_timer; /* Timer for data timeouts */ +#if IS_ENABLED(CONFIG_MMC_SDHCI_EXTERNAL_DMA) + struct dma_chan *rx_chan; + struct dma_chan *tx_chan; +#endif + u32 caps; /* CAPABILITY_0 */ u32 caps1; /* CAPABILITY_1 */ bool read_caps; /* Capability flags have been read */ @@ -785,5 +792,6 @@ void sdhci_start_tuning(struct sdhci_host *host); void sdhci_end_tuning(struct sdhci_host *host); void sdhci_reset_tuning(struct sdhci_host *host); void sdhci_send_tuning(struct sdhci_host *host, u32 opcode); +void sdhci_switch_external_dma(struct sdhci_host *host, bool en); #endif /* __SDHCI_HW_H */