From patchwork Fri Jul 20 11:50:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dilip Kota X-Patchwork-Id: 10536501 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4C0BE602CA for ; Fri, 20 Jul 2018 11:55:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 372CE293F2 for ; Fri, 20 Jul 2018 11:55:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2AD7129615; Fri, 20 Jul 2018 11:55:59 +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=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID 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 AC749293F2 for ; Fri, 20 Jul 2018 11:55:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727749AbeGTMnu (ORCPT ); Fri, 20 Jul 2018 08:43:50 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:44506 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727410AbeGTMnt (ORCPT ); Fri, 20 Jul 2018 08:43:49 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id A0E6A60131; Fri, 20 Jul 2018 11:55:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1532087755; bh=eYf4sRkGf+gKqXfJxDgpA8aUngH0zKGhQAt8Yx5nIk8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D17X17kW3gYEXE2vSRBRzxrMlwbyqS246EZk4Fd21tpTvwlK1K860Jqg2IljyCVOH TrdOymjK2juSFjMrKKEdBsXPm3//AeNMMCRgS7lLxZgH/NirTO4HaelLTSy7S5BM7Z JoXD6G6tIRiB38yJ8SvY01L6XWHKbSEvlR8OY3Tc= Received: from dkota-linux.qualcomm.com (blr-c-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.19.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: dkota@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id E857A60131; Fri, 20 Jul 2018 11:55:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1532087753; bh=eYf4sRkGf+gKqXfJxDgpA8aUngH0zKGhQAt8Yx5nIk8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h2I6r9RAE6ZTJORHsoX6Wgj5phUevsx7pxgTJAO24DojYFXnAXd/2/+B4+Zb+0UrF fC8S1jHBnRNSCn/cWL/mOPu0t3xTYKnPPkBwhfqV63mXg8W7nxHRxhszbwZSeQr1Oj Y/rjbmp+buGDL/+PfKkwSLxrP4ELBPs/UeVFrPzE= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org E857A60131 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=dkota@codeaurora.org From: Dilip Kota To: timur@codeaurora.org, swboyd@chromium.org, broonie@kernel.org, mka@chromium.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Cc: linux-arm-msm@vger.kernel.org, Girish Mahadevan , Karthikeyan Ramasubramanian , Sagar Dharia , Dilip Kota Subject: [PATCH V2] spi: spi-geni-qcom: Add SPI driver support for GENI based QUP Date: Fri, 20 Jul 2018 17:20:59 +0530 Message-Id: <1532087461-3474-2-git-send-email-dkota@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1532087461-3474-1-git-send-email-dkota@codeaurora.org> References: <1532087461-3474-1-git-send-email-dkota@codeaurora.org> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Girish Mahadevan This driver supports GENI based SPI Controller in the Qualcomm SOCs. The Qualcomm Generic Interface (GENI) is a programmable module supporting a wide range of serial interfaces including SPI. This driver supports SPI operations using FIFO mode of transfer. Change-Id: Ib2c7feba5a2fc4015bc83319b233b4356f7d3190 Signed-off-by: Girish Mahadevan Signed-off-by: Karthikeyan Ramasubramanian Signed-off-by: Sagar Dharia Signed-off-by: Girish Mahadevan Reviewed-by: Rob Herring Reviewed-by: Stephen Boyd Signed-off-by: Dilip Kota --- drivers/spi/Kconfig | 12 + drivers/spi/Makefile | 1 + drivers/spi/spi-geni-qcom.c | 685 ++++++++++++++++++++++++++++++++++++++ include/linux/spi/spi-geni-qcom.h | 14 + 4 files changed, 712 insertions(+) create mode 100644 drivers/spi/spi-geni-qcom.c create mode 100644 include/linux/spi/spi-geni-qcom.h diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index ad5d68e..d4aa755 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -533,6 +533,18 @@ config SPI_QUP This driver can also be built as a module. If so, the module will be called spi_qup. +config SPI_QCOM_GENI + tristate "Qualcomm SPI controller with QUP interface" + depends on QCOM_GENI_SE + help + This driver supports GENI serial engine based SPI controller in + master mode on the Qualcomm Technologies Inc.'s SoCs. If you say + yes to this option, support will be included for the built-in SPI + interface on the Qualcomm Technologies Inc.'s SoCs. + + This driver can also be built as a module. If so, the module + will be called spi-geni-qcom. + config SPI_S3C24XX tristate "Samsung S3C24XX series SPI" depends on ARCH_S3C24XX diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index cb1f437..98337cf 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -74,6 +74,7 @@ obj-$(CONFIG_SPI_PPC4xx) += spi-ppc4xx.o spi-pxa2xx-platform-objs := spi-pxa2xx.o spi-pxa2xx-dma.o obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o +obj-$(CONFIG_SPI_QCOM_GENI) += spi-geni-qcom.o obj-$(CONFIG_SPI_QUP) += spi-qup.o obj-$(CONFIG_SPI_ROCKCHIP) += spi-rockchip.o obj-$(CONFIG_SPI_RB4XX) += spi-rb4xx.o diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c new file mode 100644 index 0000000..95381b8 --- /dev/null +++ b/drivers/spi/spi-geni-qcom.c @@ -0,0 +1,685 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2017-2018, The Linux foundation. All rights reserved. + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* SPI SE specific registers and respective register fields */ +#define SE_SPI_CPHA 0x224 +#define CPHA BIT(0) + +#define SE_SPI_LOOPBACK 0x22c +#define LOOPBACK_ENABLE 0x1 +#define NORMAL_MODE 0x0 +#define LOOPBACK_MSK GENMASK(1, 0) + +#define SE_SPI_CPOL 0x230 +#define CPOL BIT(2) + +#define SE_SPI_DEMUX_OUTPUT_INV 0x24c +#define CS_DEMUX_OUTPUT_INV_MSK GENMASK(3, 0) + +#define SE_SPI_DEMUX_SEL 0x250 +#define CS_DEMUX_OUTPUT_SEL GENMASK(3, 0) + +#define SE_SPI_TRANS_CFG 0x25c +#define CS_TOGGLE BIT(0) + +#define SE_SPI_WORD_LEN 0x268 +#define WORD_LEN_MSK GENMASK(9, 0) +#define MIN_WORD_LEN 4 + +#define SE_SPI_TX_TRANS_LEN 0x26c +#define SE_SPI_RX_TRANS_LEN 0x270 +#define TRANS_LEN_MSK GENMASK(23, 0) + +#define SE_SPI_PRE_POST_CMD_DLY 0x274 + +#define SE_SPI_DELAY_COUNTERS 0x278 +#define SPI_INTER_WORDS_DELAY_MSK GENMASK(9, 0) +#define SPI_CS_CLK_DELAY_MSK GENMASK(19, 10) +#define SPI_CS_CLK_DELAY_SHFT 10 + +/* M_CMD OP codes for SPI */ +#define SPI_TX_ONLY 1 +#define SPI_RX_ONLY 2 +#define SPI_FULL_DUPLEX 3 +#define SPI_TX_RX 7 +#define SPI_CS_ASSERT 8 +#define SPI_CS_DEASSERT 9 +#define SPI_SCK_ONLY 10 +/* M_CMD params for SPI */ +#define SPI_PRE_CMD_DELAY BIT(0) +#define TIMESTAMP_BEFORE BIT(1) +#define FRAGMENTATION BIT(2) +#define TIMESTAMP_AFTER BIT(3) +#define POST_CMD_DELAY BIT(4) + +static irqreturn_t geni_spi_isr(int irq, void *data); + +struct spi_geni_master { + struct geni_se se; + int irq; + struct device *dev; + int rx_fifo_depth; + int tx_fifo_depth; + int tx_fifo_width; + int tx_wm; + bool setup; + u32 cur_speed_hz; + int cur_word_len; + unsigned int tx_rem_bytes; + unsigned int rx_rem_bytes; + struct spi_transfer *cur_xfer; + struct completion xfer_done; + int oversampling; +}; + +static int get_spi_clk_cfg(u32 speed_hz, struct spi_geni_master *mas, + int *clk_idx, int *clk_div) +{ + unsigned long sclk_freq; + struct geni_se *se = &mas->se; + int ret; + + ret = geni_se_clk_freq_match(&mas->se, + (speed_hz * mas->oversampling), clk_idx, + &sclk_freq, true); + if (ret) { + dev_err(mas->dev, "%s: Failed(%d) to find src clk for 0x%x\n", + __func__, ret, speed_hz); + return ret; + } + + *clk_div = ((sclk_freq / mas->oversampling) / speed_hz); + if (!(*clk_div)) { + dev_err(mas->dev, "%s:Err:sclk:%lu oversampling:%d speed:%u\n", + __func__, sclk_freq, mas->oversampling, speed_hz); + return -EINVAL; + } + + dev_dbg(mas->dev, "%s: req %u sclk %lu, idx %d, div %d\n", __func__, + speed_hz, sclk_freq, *clk_idx, *clk_div); + ret = clk_set_rate(se->clk, sclk_freq); + if (ret) + dev_err(mas->dev, "%s: clk_set_rate failed %d\n", + __func__, ret); + return ret; +} + +static void spi_setup_word_len(struct spi_geni_master *mas, u32 mode, + int bits_per_word) +{ + int pack_words = 1; + bool msb_first = (mode & SPI_LSB_FIRST) ? false : true; + struct geni_se *se = &mas->se; + u32 word_len; + + word_len = readl_relaxed(se->base + SE_SPI_WORD_LEN); + + /* + * If bits_per_word isn't a byte aligned value, set the packing to be + * 1 SPI word per FIFO word. + */ + if (!(mas->tx_fifo_width % bits_per_word)) + pack_words = mas->tx_fifo_width / bits_per_word; + word_len &= ~WORD_LEN_MSK; + word_len |= ((bits_per_word - MIN_WORD_LEN) & WORD_LEN_MSK); + geni_se_config_packing(&mas->se, bits_per_word, pack_words, msb_first, + true, true); + writel_relaxed(word_len, se->base + SE_SPI_WORD_LEN); +} + +static int setup_fifo_params(struct spi_device *spi_slv, + struct spi_master *spi) +{ + struct spi_geni_master *mas = spi_master_get_devdata(spi); + struct geni_se *se = &mas->se; + u16 mode = spi_slv->mode; + u32 loopback_cfg = readl_relaxed(se->base + SE_SPI_LOOPBACK); + u32 cpol = readl_relaxed(se->base + SE_SPI_CPOL); + u32 cpha = readl_relaxed(se->base + SE_SPI_CPHA); + u32 demux_sel = 0; + u32 demux_output_inv = 0; + u32 clk_sel = 0; + u32 m_clk_cfg = 0; + int ret = 0; + int idx; + int div; + struct spi_geni_qcom_ctrl_data *delay_params = NULL; + u32 spi_delay_params = 0; + + loopback_cfg &= ~LOOPBACK_MSK; + cpol &= ~CPOL; + cpha &= ~CPHA; + + if (mode & SPI_LOOP) + loopback_cfg |= LOOPBACK_ENABLE; + + if (mode & SPI_CPOL) + cpol |= CPOL; + + if (mode & SPI_CPHA) + cpha |= CPHA; + + if (spi_slv->mode & SPI_CS_HIGH) + demux_output_inv |= BIT(spi_slv->chip_select); + + if (spi_slv->controller_data) { + u32 cs_clk_delay = 0; + u32 inter_words_delay = 0; + + delay_params = + (struct spi_geni_qcom_ctrl_data *) spi_slv->controller_data; + cs_clk_delay = + (delay_params->spi_cs_clk_delay << SPI_CS_CLK_DELAY_SHFT) + & SPI_CS_CLK_DELAY_MSK; + inter_words_delay = + delay_params->spi_inter_words_delay & + SPI_INTER_WORDS_DELAY_MSK; + spi_delay_params = + (inter_words_delay | cs_clk_delay); + } + + demux_sel = spi_slv->chip_select; + mas->cur_speed_hz = spi_slv->max_speed_hz; + mas->cur_word_len = spi_slv->bits_per_word; + + ret = get_spi_clk_cfg(mas->cur_speed_hz, mas, &idx, &div); + if (ret) { + dev_err(mas->dev, "Err setting clks ret(%d) for %d\n", + ret, mas->cur_speed_hz); + return ret; + } + + clk_sel |= (idx & CLK_SEL_MSK); + m_clk_cfg |= ((div << CLK_DIV_SHFT) | SER_CLK_EN); + spi_setup_word_len(mas, spi_slv->mode, spi_slv->bits_per_word); + writel_relaxed(loopback_cfg, se->base + SE_SPI_LOOPBACK); + writel_relaxed(demux_sel, se->base + SE_SPI_DEMUX_SEL); + writel_relaxed(cpha, se->base + SE_SPI_CPHA); + writel_relaxed(cpol, se->base + SE_SPI_CPOL); + writel_relaxed(demux_output_inv, se->base + SE_SPI_DEMUX_OUTPUT_INV); + writel_relaxed(clk_sel, se->base + SE_GENI_CLK_SEL); + writel_relaxed(m_clk_cfg, se->base + GENI_SER_M_CLK_CFG); + writel_relaxed(spi_delay_params, se->base + SE_SPI_DELAY_COUNTERS); + return 0; +} + +static int spi_geni_prepare_message(struct spi_master *spi, + struct spi_message *spi_msg) +{ + int ret = 0; + struct spi_geni_master *mas = spi_master_get_devdata(spi); + struct geni_se *se = &mas->se; + + geni_se_select_mode(se, GENI_SE_FIFO); + reinit_completion(&mas->xfer_done); + ret = setup_fifo_params(spi_msg->spi, spi); + if (ret) { + dev_err(mas->dev, "%s: Couldn't select mode %d", __func__, ret); + ret = -EINVAL; + } + return ret; +} + +static int spi_geni_prepare_transfer_hardware(struct spi_master *spi) +{ + struct spi_geni_master *mas = spi_master_get_devdata(spi); + struct geni_se *se = &mas->se; + + if (!mas->setup) { + int proto = geni_se_read_proto(se); + unsigned int major; + unsigned int minor; + unsigned int step; + + if (proto != GENI_SE_SPI) { + dev_err(mas->dev, "Invalid proto %d\n", proto); + return -ENXIO; + } + mas->tx_fifo_depth = geni_se_get_tx_fifo_depth(se); + mas->rx_fifo_depth = geni_se_get_rx_fifo_depth(se); + mas->tx_fifo_width = geni_se_get_tx_fifo_width(se); + geni_se_init(se, 0x0, (mas->tx_fifo_depth - 2)); + mas->oversampling = 1; + /* Transmit an entire FIFO worth of data per IRQ */ + mas->tx_wm = 1; + geni_se_get_wrapper_version(se, major, minor, step); + if ((major == 1) && (minor == 0)) + mas->oversampling = 2; + mas->setup = 1; + } + return 0; +} + +static void setup_fifo_xfer(struct spi_transfer *xfer, + struct spi_geni_master *mas, u16 mode, + struct spi_master *spi) +{ + u32 m_cmd = 0; + u32 m_param = 0; + struct geni_se *se = &mas->se; + u32 spi_tx_cfg = readl_relaxed(se->base + SE_SPI_TRANS_CFG); + u32 trans_len = 0; + + if (xfer->bits_per_word != mas->cur_word_len) { + spi_setup_word_len(mas, mode, xfer->bits_per_word); + mas->cur_word_len = xfer->bits_per_word; + } + + /* Speed and bits per word can be overridden per transfer */ + if (xfer->speed_hz != mas->cur_speed_hz) { + int ret = 0; + u32 clk_sel = 0; + u32 m_clk_cfg = 0; + int idx = 0; + int div = 0; + + ret = get_spi_clk_cfg(xfer->speed_hz, mas, &idx, &div); + if (ret) { + dev_err(mas->dev, "%s:Err setting clks:%d\n", + __func__, ret); + return; + } + mas->cur_speed_hz = xfer->speed_hz; + clk_sel |= (idx & CLK_SEL_MSK); + m_clk_cfg |= ((div << CLK_DIV_SHFT) | SER_CLK_EN); + writel_relaxed(clk_sel, se->base + SE_GENI_CLK_SEL); + writel_relaxed(m_clk_cfg, se->base + GENI_SER_M_CLK_CFG); + } + + mas->tx_rem_bytes = 0; + mas->rx_rem_bytes = 0; + if (xfer->tx_buf && xfer->rx_buf) + m_cmd = SPI_FULL_DUPLEX; + else if (xfer->tx_buf) + m_cmd = SPI_TX_ONLY; + else if (xfer->rx_buf) + m_cmd = SPI_RX_ONLY; + + spi_tx_cfg &= ~CS_TOGGLE; + if (!(mas->cur_word_len % MIN_WORD_LEN)) { + trans_len = + ((xfer->len * BITS_PER_BYTE) / + mas->cur_word_len) & TRANS_LEN_MSK; + } else { + int bytes_per_word = (mas->cur_word_len / BITS_PER_BYTE) + 1; + + trans_len = (xfer->len / bytes_per_word) & TRANS_LEN_MSK; + } + + /* + * If CS change flag is set, then toggle the CS line in between + * transfers and keep CS asserted after the last transfer. + * Else if keep CS flag asserted in between transfers and de-assert + * CS after the last message. + */ + if (xfer->cs_change) { + if (list_is_last(&xfer->transfer_list, + &spi->cur_msg->transfers)) + m_param |= FRAGMENTATION; + } else { + if (!list_is_last(&xfer->transfer_list, + &spi->cur_msg->transfers)) + m_param |= FRAGMENTATION; + } + + mas->cur_xfer = xfer; + if (m_cmd & SPI_TX_ONLY) { + mas->tx_rem_bytes = xfer->len; + writel_relaxed(trans_len, se->base + SE_SPI_TX_TRANS_LEN); + } + + if (m_cmd & SPI_RX_ONLY) { + writel_relaxed(trans_len, se->base + SE_SPI_RX_TRANS_LEN); + mas->rx_rem_bytes = xfer->len; + } + writel_relaxed(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG); + geni_se_setup_m_cmd(se, m_cmd, m_param); + if (m_cmd & SPI_TX_ONLY) + writel_relaxed(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG); +} + +static void handle_fifo_timeout(struct spi_master *spi, + struct spi_message *msg) +{ + struct spi_geni_master *mas = spi_master_get_devdata(spi); + unsigned long timeout; + struct geni_se *se = &mas->se; + + reinit_completion(&mas->xfer_done); + geni_se_cancel_m_cmd(se); + writel_relaxed(0, se->base + SE_GENI_TX_WATERMARK_REG); + timeout = wait_for_completion_timeout(&mas->xfer_done, HZ); + if (!timeout) { + reinit_completion(&mas->xfer_done); + geni_se_abort_m_cmd(se); + timeout = wait_for_completion_timeout(&mas->xfer_done, + HZ); + if (!timeout) + dev_err(mas->dev, + "Failed to cancel/abort m_cmd\n"); + } +} + +static int spi_geni_transfer_one(struct spi_master *spi, + struct spi_device *slv, + struct spi_transfer *xfer) +{ + struct spi_geni_master *mas = spi_master_get_devdata(spi); + + setup_fifo_xfer(xfer, mas, slv->mode, spi); + return 1; +} + +static void geni_spi_handle_tx(struct spi_geni_master *mas) +{ + int i = 0; + int tx_fifo_width = mas->tx_fifo_width / BITS_PER_BYTE; + int max_bytes = 0; + const u8 *tx_buf; + struct geni_se *se = &mas->se; + + if (!mas->cur_xfer) + return; + + /* + * For non-byte aligned bits-per-word values. (e.g 9) + * The FIFO packing is set to 1 SPI word per FIFO word. + * Assumption is that each SPI word will be accomodated in + * ceil (bits_per_word / bits_per_byte) + * and the next SPI word starts at the next byte. + * In such cases, we can fit 1 SPI word per FIFO word so adjust the + * max byte that can be sent per IRQ accordingly. + */ + if ((mas->tx_fifo_width % mas->cur_word_len)) + max_bytes = (mas->tx_fifo_depth - mas->tx_wm) * + ((mas->cur_word_len / BITS_PER_BYTE) + 1); + else + max_bytes = (mas->tx_fifo_depth - mas->tx_wm) * tx_fifo_width; + tx_buf = mas->cur_xfer->tx_buf; + tx_buf += (mas->cur_xfer->len - mas->tx_rem_bytes); + max_bytes = min_t(int, mas->tx_rem_bytes, max_bytes); + while (i < max_bytes) { + int j; + u32 fifo_word = 0; + u8 *fifo_byte; + int bytes_per_fifo = tx_fifo_width; + int bytes_to_write = 0; + + if ((mas->tx_fifo_width % mas->cur_word_len)) + bytes_per_fifo = + (mas->cur_word_len / BITS_PER_BYTE) + 1; + bytes_to_write = min_t(int, max_bytes - i, bytes_per_fifo); + fifo_byte = (u8 *)&fifo_word; + for (j = 0; j < bytes_to_write; j++) + fifo_byte[j] = tx_buf[i++]; + iowrite32_rep(se->base + SE_GENI_TX_FIFOn, &fifo_word, 1); + } + mas->tx_rem_bytes -= max_bytes; + if (!mas->tx_rem_bytes) + writel_relaxed(0, se->base + SE_GENI_TX_WATERMARK_REG); +} + +static void geni_spi_handle_rx(struct spi_geni_master *mas) +{ + int i = 0; + struct geni_se *se = &mas->se; + int fifo_width = mas->tx_fifo_width / BITS_PER_BYTE; + u32 rx_fifo_status = readl_relaxed(se->base + SE_GENI_RX_FIFO_STATUS); + int rx_bytes = 0; + int rx_wc = 0; + u8 *rx_buf; + + if (!mas->cur_xfer) + return; + + rx_buf = mas->cur_xfer->rx_buf; + rx_wc = rx_fifo_status & RX_FIFO_WC_MSK; + if (rx_fifo_status & RX_LAST) { + int rx_last_byte_valid = + (rx_fifo_status & RX_LAST_BYTE_VALID_MSK) + >> RX_LAST_BYTE_VALID_SHFT; + if (rx_last_byte_valid && (rx_last_byte_valid < 4)) { + rx_wc -= 1; + rx_bytes += rx_last_byte_valid; + } + } + + /* + * For non-byte aligned bits-per-word values. (e.g 9) + * The FIFO packing is set to 1 SPI word per FIFO word. + * Assumption is that each SPI word will be accomodated in + * ceil (bits_per_word / bits_per_byte) + * and the next SPI word starts at the next byte. + */ + if (!(mas->tx_fifo_width % mas->cur_word_len)) + rx_bytes += rx_wc * fifo_width; + else + rx_bytes += rx_wc * + ((mas->cur_word_len / BITS_PER_BYTE) + 1); + rx_bytes = min_t(int, mas->rx_rem_bytes, rx_bytes); + rx_buf += (mas->cur_xfer->len - mas->rx_rem_bytes); + while (i < rx_bytes) { + u32 fifo_word = 0; + u8 *fifo_byte; + int bytes_per_fifo = fifo_width; + int read_bytes = 0; + int j; + + if ((mas->tx_fifo_width % mas->cur_word_len)) + bytes_per_fifo = + (mas->cur_word_len / BITS_PER_BYTE) + 1; + read_bytes = min_t(int, rx_bytes - i, bytes_per_fifo); + ioread32_rep(se->base + SE_GENI_RX_FIFOn, &fifo_word, 1); + fifo_byte = (u8 *)&fifo_word; + for (j = 0; j < read_bytes; j++) + rx_buf[i++] = fifo_byte[j]; + } + mas->rx_rem_bytes -= rx_bytes; +} + +static irqreturn_t geni_spi_isr(int irq, void *data) +{ + struct spi_master *spi = data; + struct spi_geni_master *mas = spi_master_get_devdata(spi); + struct geni_se *se = &mas->se; + u32 m_irq = 0; + irqreturn_t ret = IRQ_HANDLED; + + if (pm_runtime_status_suspended(mas->dev)) { + ret = IRQ_NONE; + goto exit_geni_spi_irq; + } + m_irq = readl_relaxed(se->base + SE_GENI_M_IRQ_STATUS); + if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN)) + geni_spi_handle_rx(mas); + + if ((m_irq & M_TX_FIFO_WATERMARK_EN)) + geni_spi_handle_tx(mas); + + if (m_irq & M_CMD_DONE_EN) { + spi_finalize_current_transfer(spi); + /* + * If this happens, then a CMD_DONE came before all the Tx + * buffer bytes were sent out. This is unusual, log this + * condition and disable the WM interrupt to prevent the + * system from stalling due an interrupt storm. + * If this happens when all Rx bytes haven't been received, log + * the condition. + * The only known time this can happen is if bits_per_word != 8 + * and some registers that expect xfer lengths in num spi_words + * weren't written correctly. + */ + if (mas->tx_rem_bytes) { + writel_relaxed(0, se->base + SE_GENI_TX_WATERMARK_REG); + dev_err(mas->dev, + "%s:Premature Done.tx_rem%d bpw%d\n", + __func__, mas->tx_rem_bytes, mas->cur_word_len); + } + if (mas->rx_rem_bytes) + dev_err(mas->dev, + "%s:Premature Done.rx_rem%d bpw%d\n", + __func__, mas->rx_rem_bytes, mas->cur_word_len); + } + + if ((m_irq & M_CMD_CANCEL_EN) || (m_irq & M_CMD_ABORT_EN)) + complete(&mas->xfer_done); +exit_geni_spi_irq: + writel_relaxed(m_irq, se->base + SE_GENI_M_IRQ_CLEAR); + return ret; +} + +static int spi_geni_probe(struct platform_device *pdev) +{ + int ret; + struct spi_master *spi; + struct spi_geni_master *spi_geni; + struct resource *res; + struct geni_se *se; + + spi = spi_alloc_master(&pdev->dev, sizeof(struct spi_geni_master)); + if (!spi) { + ret = -ENOMEM; + dev_err(&pdev->dev, "Failed to alloc spi struct\n"); + goto spi_geni_probe_err; + } + + platform_set_drvdata(pdev, spi); + spi_geni = spi_master_get_devdata(spi); + spi_geni->dev = &pdev->dev; + spi_geni->se.dev = &pdev->dev; + spi_geni->se.wrapper = dev_get_drvdata(pdev->dev.parent); + se = &spi_geni->se; + + spi->bus_num = -1; + spi->dev.of_node = pdev->dev.of_node; + spi_geni->se.clk = devm_clk_get(&pdev->dev, "se"); + if (IS_ERR(spi_geni->se.clk)) { + ret = PTR_ERR(spi_geni->se.clk); + dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret); + goto spi_geni_probe_err; + } + + if (of_property_read_u32(pdev->dev.of_node, "spi-max-frequency", + &spi->max_speed_hz)) { + dev_err(&pdev->dev, "Max frequency not specified.\n"); + ret = -ENXIO; + goto spi_geni_probe_err; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + se->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(se->base)) { + ret = -ENOMEM; + dev_err(&pdev->dev, "Err IO mapping iomem\n"); + goto spi_geni_probe_err; + } + + spi_geni->irq = platform_get_irq(pdev, 0); + if (spi_geni->irq < 0) { + dev_err(&pdev->dev, "Err getting IRQ\n"); + ret = spi_geni->irq; + goto spi_geni_probe_unmap; + } + ret = devm_request_irq(&pdev->dev, spi_geni->irq, geni_spi_isr, + IRQF_TRIGGER_HIGH, "spi_geni", spi); + if (ret) { + dev_err(&pdev->dev, "Request_irq failed:%d: err:%d\n", + spi_geni->irq, ret); + goto spi_geni_probe_unmap; + } + + spi->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_CS_HIGH; + spi->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); + spi->num_chipselect = 4; + spi->prepare_transfer_hardware = spi_geni_prepare_transfer_hardware; + spi->prepare_message = spi_geni_prepare_message; + spi->transfer_one = spi_geni_transfer_one; + spi->auto_runtime_pm = true; + spi->handle_err = handle_fifo_timeout; + + init_completion(&spi_geni->xfer_done); + pm_runtime_enable(&pdev->dev); + ret = devm_spi_register_master(&pdev->dev, spi); + if (ret) { + dev_err(&pdev->dev, "Failed to register SPI master\n"); + goto spi_geni_probe_unmap; + } + + dev_dbg(&pdev->dev, "%s Probed\n", __func__); + return ret; +spi_geni_probe_unmap: + devm_iounmap(&pdev->dev, se->base); +spi_geni_probe_err: + spi_master_put(spi); + return ret; +} + +static int spi_geni_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct spi_geni_master *spi_geni = spi_master_get_devdata(master); + + geni_se_resources_off(&spi_geni->se); + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); + return 0; +} + +static int __maybe_unused spi_geni_runtime_suspend(struct device *dev) +{ + struct spi_master *spi = dev_get_drvdata(dev); + struct spi_geni_master *spi_geni = spi_master_get_devdata(spi); + + return geni_se_resources_off(&spi_geni->se); +} + +static int __maybe_unused spi_geni_runtime_resume(struct device *dev) +{ + struct spi_master *spi = dev_get_drvdata(dev); + struct spi_geni_master *spi_geni = spi_master_get_devdata(spi); + + return geni_se_resources_on(&spi_geni->se); +} + +static int __maybe_unused spi_geni_suspend(struct device *dev) +{ + if (!pm_runtime_status_suspended(dev)) + return -EBUSY; + return 0; +} + +static const struct dev_pm_ops spi_geni_pm_ops = { + SET_RUNTIME_PM_OPS(spi_geni_runtime_suspend, + spi_geni_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(spi_geni_suspend, NULL) +}; + +static const struct of_device_id spi_geni_dt_match[] = { + { .compatible = "qcom,geni-spi" }, + {} +}; + +static struct platform_driver spi_geni_driver = { + .probe = spi_geni_probe, + .remove = spi_geni_remove, + .driver = { + .name = "geni_spi", + .pm = &spi_geni_pm_ops, + .of_match_table = spi_geni_dt_match, + }, +}; +module_platform_driver(spi_geni_driver); + +MODULE_DESCRIPTION("SPI driver for GENI based QUP cores"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/spi/spi-geni-qcom.h b/include/linux/spi/spi-geni-qcom.h new file mode 100644 index 0000000..dc95764 --- /dev/null +++ b/include/linux/spi/spi-geni-qcom.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Copyright (c) 2017-2018, The Linux Foundation. All rights reserved. + */ + +#ifndef __SPI_GENI_QCOM_HEADER___ +#define __SPI_GENI_QCOM_HEADER___ + +struct spi_geni_qcom_ctrl_data { + u32 spi_cs_clk_delay; + u32 spi_inter_words_delay; +}; + +#endif /*__SPI_GENI_QCOM_HEADER___*/