From patchwork Mon Nov 17 22:47:50 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Beniamino Galvani X-Patchwork-Id: 5324321 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 61186C11AC for ; Mon, 17 Nov 2014 22:54:03 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 064A820127 for ; Mon, 17 Nov 2014 22:54:02 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 82C672011D for ; Mon, 17 Nov 2014 22:54:00 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XqV9V-00072W-Qf; Mon, 17 Nov 2014 22:52:09 +0000 Received: from mail-wi0-x234.google.com ([2a00:1450:400c:c05::234]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XqV8J-000625-Mf for linux-arm-kernel@lists.infradead.org; Mon, 17 Nov 2014 22:50:59 +0000 Received: by mail-wi0-f180.google.com with SMTP id n3so3314846wiv.13 for ; Mon, 17 Nov 2014 14:50:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=xPfmV3zDAnhBozKvpUdNnn2CTFurYIEtfPOJjlGofq8=; b=STL4jbaWLN5HgMx0EncgK2+CwM7xOg6W5/RkKU8rlee4OvtdDaeERr7w7wwlYmoSJ8 i5eeH2sYyiI82p+o4yqaZ3fvwFcGl7U19je57DGDrJvwgX/ZXpmbdln/j/LI/o9Zk+14 F4MJSoKN8YSz3f//J0QSV2u0ieapDdjaIM7fbE0iMXLKibIPVtwzRYTvoYJhZYxFnLTM bku+pJJWhX60P9mf5ClMz7/w3yhEGMoxsSY4T+fGjDSQZxTqZiE6T20AF0wU46uNtvPU eHmhh6X8ohsbkgRxQA4UiuuxJyB71vBOe9valrhk0ImH2JWEIFK3i1LQKGmGXMR527Pe lUFw== X-Received: by 10.180.212.110 with SMTP id nj14mr34786691wic.45.1416264633735; Mon, 17 Nov 2014 14:50:33 -0800 (PST) Received: from sark.local (host115-93-dynamic.40-79-r.retail.telecomitalia.it. [79.40.93.115]) by mx.google.com with ESMTPSA id cu9sm53383417wjb.0.2014.11.17.14.50.30 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 17 Nov 2014 14:50:32 -0800 (PST) From: Beniamino Galvani To: Mark Brown Subject: [PATCH v2 3/4] spi: meson: Add support for Amlogic Meson SPIFC Date: Mon, 17 Nov 2014 23:47:50 +0100 Message-Id: <1416264471-774-4-git-send-email-b.galvani@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1416264471-774-1-git-send-email-b.galvani@gmail.com> References: <1416264471-774-1-git-send-email-b.galvani@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141117_145056_129268_4B0AF3FC X-CRM114-Status: GOOD ( 27.34 ) X-Spam-Score: -0.8 (/) Cc: Mark Rutland , devicetree@vger.kernel.org, Russell King , Victor Wan , Pawel Moll , Ian Campbell , linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, Beniamino Galvani , Rob Herring , Kumar Gala , Carlo Caione , Jerry Cao , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW, T_DKIM_INVALID, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This is a driver for the Amlogic Meson SPIFC (SPI flash controller), which is one of the two SPI controllers available on the SoC. It doesn't support DMA and has a 64-byte unified transmit/receive buffer. The device is optimized for interfacing with SPI NOR memories and allows the execution of standard operations such as read, page program, sector erase, etc. in a simplified way, toggling a bit in a dedicated register. The driver doesn't use those predefined commands and relies only on custom transfers. Signed-off-by: Beniamino Galvani --- drivers/spi/Kconfig | 7 + drivers/spi/Makefile | 1 + drivers/spi/spi-meson-spifc.c | 461 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 469 insertions(+) create mode 100644 drivers/spi/spi-meson-spifc.c diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 84e7c9e..70f20b9 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -301,6 +301,13 @@ config SPI_FSL_ESPI From MPC8536, 85xx platform uses the controller, and all P10xx, P20xx, P30xx,P40xx, P50xx uses this controller. +config SPI_MESON_SPIFC + tristate "Amlogic Meson SPIFC controller" + depends on ARCH_MESON || COMPILE_TEST + help + This enables master mode support for the SPIFC (SPI flash + controller) available in Amlogic Meson SoCs. + config SPI_OC_TINY tristate "OpenCores tiny SPI" depends on GPIOLIB diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 78f24ca..9b8a747 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -42,6 +42,7 @@ obj-$(CONFIG_SPI_FSL_SPI) += spi-fsl-spi.o obj-$(CONFIG_SPI_GPIO) += spi-gpio.o obj-$(CONFIG_SPI_IMX) += spi-imx.o obj-$(CONFIG_SPI_LM70_LLP) += spi-lm70llp.o +obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o obj-$(CONFIG_SPI_MPC52xx_PSC) += spi-mpc52xx-psc.o obj-$(CONFIG_SPI_MPC52xx) += spi-mpc52xx.o diff --git a/drivers/spi/spi-meson-spifc.c b/drivers/spi/spi-meson-spifc.c new file mode 100644 index 0000000..68be0e0 --- /dev/null +++ b/drivers/spi/spi-meson-spifc.c @@ -0,0 +1,461 @@ +/* + * Driver for Amlogic Meson SPI flash controller (SPIFC) + * + * Copyright (C) 2014 Beniamino Galvani + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* register map */ +#define REG_CMD 0x00 +#define REG_ADDR 0x04 +#define REG_CTRL 0x08 +#define REG_CTRL1 0x0c +#define REG_STATUS 0x10 +#define REG_CTRL2 0x14 +#define REG_CLOCK 0x18 +#define REG_USER 0x1c +#define REG_USER1 0x20 +#define REG_USER2 0x24 +#define REG_USER3 0x28 +#define REG_USER4 0x2c +#define REG_SLAVE 0x30 +#define REG_SLAVE1 0x34 +#define REG_SLAVE2 0x38 +#define REG_SLAVE3 0x3c +#define REG_C0 0x40 +#define REG_B8 0x60 +#define REG_MAX 0x7c + +/* register fields */ +#define CMD_USER BIT(18) +#define CTRL_ENABLE_AHB BIT(17) +#define CLOCK_SOURCE BIT(31) +#define CLOCK_DIV_SHIFT 12 +#define CLOCK_DIV_MASK (0x3f << CLOCK_DIV_SHIFT) +#define CLOCK_CNT_HIGH_SHIFT 6 +#define CLOCK_CNT_HIGH_MASK (0x3f << CLOCK_CNT_HIGH_SHIFT) +#define CLOCK_CNT_LOW_SHIFT 0 +#define CLOCK_CNT_LOW_MASK (0x3f << CLOCK_CNT_LOW_SHIFT) +#define USER_DIN_EN_MS BIT(0) +#define USER_CMP_MODE BIT(2) +#define USER_UC_DOUT_SEL BIT(27) +#define USER_UC_DIN_SEL BIT(28) +#define USER_UC_MASK ((BIT(5) - 1) << 27) +#define USER1_BN_UC_DOUT_SHIFT 17 +#define USER1_BN_UC_DOUT_MASK (0xff << 16) +#define USER1_BN_UC_DIN_SHIFT 8 +#define USER1_BN_UC_DIN_MASK (0xff << 8) +#define USER4_CS_ACT BIT(30) +#define SLAVE_TRST_DONE BIT(4) +#define SLAVE_OP_MODE BIT(30) +#define SLAVE_SW_RST BIT(31) + +#define SPIFC_BUFFER_SIZE 64 + +/** + * struct meson_spifc + * @master: the SPI master + * @regmap: regmap for device registers + * @clk: input clock of the built-in baud rate generator + * @device: the device structure + */ +struct meson_spifc { + struct spi_master *master; + struct regmap *regmap; + struct clk *clk; + struct device *dev; +}; + +static struct regmap_config spifc_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .max_register = REG_MAX, +}; + +/** + * meson_spifc_wait_ready() - wait for the current operation to terminate + * @spifc: the Meson SPI device + * Return: 0 on success, a negative value on error + */ +static int meson_spifc_wait_ready(struct meson_spifc *spifc) +{ + unsigned long deadline = jiffies + msecs_to_jiffies(5); + u32 data; + + do { + regmap_read(spifc->regmap, REG_SLAVE, &data); + if (data & SLAVE_TRST_DONE) + return 0; + cond_resched(); + } while (!time_after(jiffies, deadline)); + + return -ETIMEDOUT; +} + +/** + * meson_spifc_drain_buffer() - copy data from device buffer to memory + * @spifc: the Meson SPI device + * @buf: the destination buffer + * @len: number of bytes to copy + */ +static void meson_spifc_drain_buffer(struct meson_spifc *spifc, u8 *buf, + int len) +{ + u32 data; + int i = 0; + + while (i < len) { + regmap_read(spifc->regmap, REG_C0 + i, &data); + + if (len - i >= 4) { + *((u32 *)buf) = data; + buf += 4; + } else { + memcpy(buf, &data, len - i); + break; + } + i += 4; + } +} + +/** + * meson_spifc_fill_buffer() - copy data from memory to device buffer + * @spifc: the Meson SPI device + * @buf: the source buffer + * @len: number of bytes to copy + */ +static void meson_spifc_fill_buffer(struct meson_spifc *spifc, const u8 *buf, + int len) +{ + u32 data; + int i = 0; + + while (i < len) { + if (len - i >= 4) + data = *(u32 *)buf; + else + memcpy(&data, buf, len - i); + + regmap_write(spifc->regmap, REG_C0 + i, data); + + buf += 4; + i += 4; + } +} + +/** + * meson_spifc_setup_speed() - program the clock divider + * @spifc: the Meson SPI device + * @speed: desired speed in Hz + */ +void meson_spifc_setup_speed(struct meson_spifc *spifc, u32 speed) +{ + unsigned long parent, value; + int n; + + parent = clk_get_rate(spifc->clk); + n = max_t(int, parent / speed - 1, 1); + + dev_dbg(spifc->dev, "parent %lu, speed %u, n %d\n", parent, + speed, n); + + value = (n << CLOCK_DIV_SHIFT) & CLOCK_DIV_MASK; + value |= (n << CLOCK_CNT_LOW_SHIFT) & CLOCK_CNT_LOW_MASK; + value |= (((n + 1) / 2 - 1) << CLOCK_CNT_HIGH_SHIFT) & + CLOCK_CNT_HIGH_MASK; + + regmap_write(spifc->regmap, REG_CLOCK, value); +} + +/** + * meson_spifc_txrx() - transfer a chunk of data + * @spifc: the Meson SPI device + * @xfer: the current SPI transfer + * @offset: offset of the data to transfer + * @len: length of the data to transfer + * @last_xfer: whether this is the last transfer of the message + * @last_chunk: whether this is the last chunk of the transfer + * Return: 0 on success, a negative value on error + */ +static int meson_spifc_txrx(struct meson_spifc *spifc, + struct spi_transfer *xfer, + int offset, int len, bool last_xfer, + bool last_chunk) +{ + bool keep_cs = true; + int ret; + + if (xfer->tx_buf) + meson_spifc_fill_buffer(spifc, xfer->tx_buf + offset, len); + + /* enable DOUT stage */ + regmap_update_bits(spifc->regmap, REG_USER, USER_UC_MASK, + USER_UC_DOUT_SEL); + regmap_write(spifc->regmap, REG_USER1, + (8 * len - 1) << USER1_BN_UC_DOUT_SHIFT); + + /* enable data input during DOUT */ + regmap_update_bits(spifc->regmap, REG_USER, USER_DIN_EN_MS, + USER_DIN_EN_MS); + + if (last_chunk) { + if (last_xfer) + keep_cs = xfer->cs_change; + else + keep_cs = !xfer->cs_change; + } + + regmap_update_bits(spifc->regmap, REG_USER4, USER4_CS_ACT, + keep_cs ? USER4_CS_ACT : 0); + + /* clear transition done bit */ + regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_TRST_DONE, 0); + /* start transfer */ + regmap_update_bits(spifc->regmap, REG_CMD, CMD_USER, CMD_USER); + + ret = meson_spifc_wait_ready(spifc); + + if (!ret && xfer->rx_buf) + meson_spifc_drain_buffer(spifc, xfer->rx_buf + offset, len); + + return ret; +} + +/** + * meson_spifc_transfer_one() - perform a single transfer + * @master: the SPI master + * @spi: the SPI device + * @xfer: the current SPI transfer + * Return: 0 on success, a negative value on error + */ +static int meson_spifc_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct meson_spifc *spifc = spi_master_get_devdata(master); + int len, done = 0, ret = 0; + + meson_spifc_setup_speed(spifc, xfer->speed_hz); + + regmap_update_bits(spifc->regmap, REG_CTRL, CTRL_ENABLE_AHB, 0); + + while (done < xfer->len && !ret) { + len = min_t(int, xfer->len - done, SPIFC_BUFFER_SIZE); + ret = meson_spifc_txrx(spifc, xfer, done, len, + xfer->last, done + len >= xfer->len); + done += len; + } + + regmap_update_bits(spifc->regmap, REG_CTRL, CTRL_ENABLE_AHB, + CTRL_ENABLE_AHB); + + return ret; +} + +/** + * meson_spifc_hw_init() - reset and initialize the SPI controller + * @spifc: the Meson SPI device + */ +static void meson_spifc_hw_init(struct meson_spifc *spifc) +{ + /* reset device */ + regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_SW_RST, + SLAVE_SW_RST); + /* disable compatible mode */ + regmap_update_bits(spifc->regmap, REG_USER, USER_CMP_MODE, 0); + /* set master mode */ + regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_OP_MODE, 0); +} + +static int meson_spifc_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct meson_spifc *spifc; + struct resource *res; + void __iomem *base; + unsigned int rate; + int ret = 0; + + master = spi_alloc_master(&pdev->dev, sizeof(struct meson_spifc)); + if (!master) + return -ENOMEM; + + platform_set_drvdata(pdev, master); + + spifc = spi_master_get_devdata(master); + spifc->dev = &pdev->dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(spifc->dev, res); + if (IS_ERR(base)) { + ret = PTR_ERR(base); + goto out_err; + } + + spifc->regmap = devm_regmap_init_mmio(spifc->dev, base, + &spifc_regmap_config); + if (IS_ERR(spifc->regmap)) { + ret = PTR_ERR(spifc->regmap); + goto out_err; + } + + spifc->clk = devm_clk_get(spifc->dev, NULL); + if (IS_ERR(spifc->clk)) { + dev_err(spifc->dev, "missing clock\n"); + ret = PTR_ERR(spifc->clk); + goto out_err; + } + + ret = clk_prepare_enable(spifc->clk); + if (ret) { + dev_err(spifc->dev, "can't prepare clock\n"); + goto out_err; + } + + rate = clk_get_rate(spifc->clk); + + master->num_chipselect = 1; + master->dev.of_node = pdev->dev.of_node; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->auto_runtime_pm = true; + master->transfer_one = meson_spifc_transfer_one; + master->min_speed_hz = rate >> 6; + master->max_speed_hz = rate >> 1; + + meson_spifc_hw_init(spifc); + + pm_runtime_set_active(spifc->dev); + pm_runtime_enable(spifc->dev); + + ret = devm_spi_register_master(spifc->dev, master); + if (ret) { + dev_err(spifc->dev, "failed to register spi master\n"); + goto out_clk; + } + + return 0; +out_clk: + clk_disable_unprepare(spifc->clk); +out_err: + spi_master_put(master); + return ret; +} + +static int meson_spifc_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + + pm_runtime_get_sync(&pdev->dev); + clk_disable_unprepare(spifc->clk); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int meson_spifc_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + if (!pm_runtime_suspended(dev)) + clk_disable_unprepare(spifc->clk); + + return 0; +} + +static int meson_spifc_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + int ret; + + if (!pm_runtime_suspended(dev)) { + ret = clk_prepare_enable(spifc->clk); + if (ret) + return ret; + } + + meson_spifc_hw_init(spifc); + + ret = spi_master_resume(master); + if (ret) + clk_disable_unprepare(spifc->clk); + + return ret; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM_RUNTIME +static int meson_spifc_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + + clk_disable_unprepare(spifc->clk); + + return 0; +} + +static int meson_spifc_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + + return clk_prepare_enable(spifc->clk); +} +#endif /* CONFIG_PM_RUNTIME */ + +static const struct dev_pm_ops meson_spifc_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(meson_spifc_suspend, meson_spifc_resume) + SET_RUNTIME_PM_OPS(meson_spifc_runtime_suspend, + meson_spifc_runtime_resume, + NULL) +}; + +static const struct of_device_id meson_spifc_dt_match[] = { + { .compatible = "amlogic,meson6-spifc", }, + { }, +}; + +static struct platform_driver meson_spifc_driver = { + .probe = meson_spifc_probe, + .remove = meson_spifc_remove, + .driver = { + .name = "meson-spifc", + .of_match_table = of_match_ptr(meson_spifc_dt_match), + .pm = &meson_spifc_pm_ops, + }, +}; + +module_platform_driver(meson_spifc_driver); + +MODULE_AUTHOR("Beniamino Galvani "); +MODULE_DESCRIPTION("Amlogic Meson SPIFC driver"); +MODULE_LICENSE("GPL v2");