diff options
Diffstat (limited to 'drivers/spi/spi-qcom-qspi.c')
| -rw-r--r-- | drivers/spi/spi-qcom-qspi.c | 581 |
1 files changed, 581 insertions, 0 deletions
diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c new file mode 100644 index 000000000000..b8163b40bb92 --- /dev/null +++ b/drivers/spi/spi-qcom-qspi.c @@ -0,0 +1,581 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2017-2018, The Linux foundation. All rights reserved. + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/pm_runtime.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi-mem.h> + + +#define QSPI_NUM_CS 2 +#define QSPI_BYTES_PER_WORD 4 + +#define MSTR_CONFIG 0x0000 +#define FULL_CYCLE_MODE BIT(3) +#define FB_CLK_EN BIT(4) +#define PIN_HOLDN BIT(6) +#define PIN_WPN BIT(7) +#define DMA_ENABLE BIT(8) +#define BIG_ENDIAN_MODE BIT(9) +#define SPI_MODE_MSK 0xc00 +#define SPI_MODE_SHFT 10 +#define CHIP_SELECT_NUM BIT(12) +#define SBL_EN BIT(13) +#define LPA_BASE_MSK 0x3c000 +#define LPA_BASE_SHFT 14 +#define TX_DATA_DELAY_MSK 0xc0000 +#define TX_DATA_DELAY_SHFT 18 +#define TX_CLK_DELAY_MSK 0x300000 +#define TX_CLK_DELAY_SHFT 20 +#define TX_CS_N_DELAY_MSK 0xc00000 +#define TX_CS_N_DELAY_SHFT 22 +#define TX_DATA_OE_DELAY_MSK 0x3000000 +#define TX_DATA_OE_DELAY_SHFT 24 + +#define AHB_MASTER_CFG 0x0004 +#define HMEM_TYPE_START_MID_TRANS_MSK 0x7 +#define HMEM_TYPE_START_MID_TRANS_SHFT 0 +#define HMEM_TYPE_LAST_TRANS_MSK 0x38 +#define HMEM_TYPE_LAST_TRANS_SHFT 3 +#define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_MSK 0xc0 +#define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_SHFT 6 +#define HMEMTYPE_READ_TRANS_MSK 0x700 +#define HMEMTYPE_READ_TRANS_SHFT 8 +#define HSHARED BIT(11) +#define HINNERSHARED BIT(12) + +#define MSTR_INT_EN 0x000C +#define MSTR_INT_STATUS 0x0010 +#define RESP_FIFO_UNDERRUN BIT(0) +#define RESP_FIFO_NOT_EMPTY BIT(1) +#define RESP_FIFO_RDY BIT(2) +#define HRESP_FROM_NOC_ERR BIT(3) +#define WR_FIFO_EMPTY BIT(9) +#define WR_FIFO_FULL BIT(10) +#define WR_FIFO_OVERRUN BIT(11) +#define TRANSACTION_DONE BIT(16) +#define QSPI_ERR_IRQS (RESP_FIFO_UNDERRUN | HRESP_FROM_NOC_ERR | \ + WR_FIFO_OVERRUN) +#define QSPI_ALL_IRQS (QSPI_ERR_IRQS | RESP_FIFO_RDY | \ + WR_FIFO_EMPTY | WR_FIFO_FULL | \ + TRANSACTION_DONE) + +#define PIO_XFER_CTRL 0x0014 +#define REQUEST_COUNT_MSK 0xffff + +#define PIO_XFER_CFG 0x0018 +#define TRANSFER_DIRECTION BIT(0) +#define MULTI_IO_MODE_MSK 0xe +#define MULTI_IO_MODE_SHFT 1 +#define TRANSFER_FRAGMENT BIT(8) +#define SDR_1BIT 1 +#define SDR_2BIT 2 +#define SDR_4BIT 3 +#define DDR_1BIT 5 +#define DDR_2BIT 6 +#define DDR_4BIT 7 +#define DMA_DESC_SINGLE_SPI 1 +#define DMA_DESC_DUAL_SPI 2 +#define DMA_DESC_QUAD_SPI 3 + +#define PIO_XFER_STATUS 0x001c +#define WR_FIFO_BYTES_MSK 0xffff0000 +#define WR_FIFO_BYTES_SHFT 16 + +#define PIO_DATAOUT_1B 0x0020 +#define PIO_DATAOUT_4B 0x0024 + +#define RD_FIFO_STATUS 0x002c +#define FIFO_EMPTY BIT(11) +#define WR_CNTS_MSK 0x7f0 +#define WR_CNTS_SHFT 4 +#define RDY_64BYTE BIT(3) +#define RDY_32BYTE BIT(2) +#define RDY_16BYTE BIT(1) +#define FIFO_RDY BIT(0) + +#define RD_FIFO_CFG 0x0028 +#define CONTINUOUS_MODE BIT(0) + +#define RD_FIFO_RESET 0x0030 +#define RESET_FIFO BIT(0) + +#define CUR_MEM_ADDR 0x0048 +#define HW_VERSION 0x004c +#define RD_FIFO 0x0050 +#define SAMPLING_CLK_CFG 0x0090 +#define SAMPLING_CLK_STATUS 0x0094 + + +enum qspi_dir { + QSPI_READ, + QSPI_WRITE, +}; + +struct qspi_xfer { + union { + const void *tx_buf; + void *rx_buf; + }; + unsigned int rem_bytes; + unsigned int buswidth; + enum qspi_dir dir; + bool is_last; +}; + +enum qspi_clocks { + QSPI_CLK_CORE, + QSPI_CLK_IFACE, + QSPI_NUM_CLKS +}; + +struct qcom_qspi { + void __iomem *base; + struct device *dev; + struct clk_bulk_data clks[QSPI_NUM_CLKS]; + struct qspi_xfer xfer; + /* Lock to protect data accessed by IRQs */ + spinlock_t lock; +}; + +static u32 qspi_buswidth_to_iomode(struct qcom_qspi *ctrl, + unsigned int buswidth) +{ + switch (buswidth) { + case 1: + return SDR_1BIT << MULTI_IO_MODE_SHFT; + case 2: + return SDR_2BIT << MULTI_IO_MODE_SHFT; + case 4: + return SDR_4BIT << MULTI_IO_MODE_SHFT; + default: + dev_warn_once(ctrl->dev, + "Unexpected bus width: %u\n", buswidth); + return SDR_1BIT << MULTI_IO_MODE_SHFT; + } +} + +static void qcom_qspi_pio_xfer_cfg(struct qcom_qspi *ctrl) +{ + u32 pio_xfer_cfg; + const struct qspi_xfer *xfer; + + xfer = &ctrl->xfer; + pio_xfer_cfg = readl(ctrl->base + PIO_XFER_CFG); + pio_xfer_cfg &= ~TRANSFER_DIRECTION; + pio_xfer_cfg |= xfer->dir; + if (xfer->is_last) + pio_xfer_cfg &= ~TRANSFER_FRAGMENT; + else + pio_xfer_cfg |= TRANSFER_FRAGMENT; + pio_xfer_cfg &= ~MULTI_IO_MODE_MSK; + pio_xfer_cfg |= qspi_buswidth_to_iomode(ctrl, xfer->buswidth); + + writel(pio_xfer_cfg, ctrl->base + PIO_XFER_CFG); +} + +static void qcom_qspi_pio_xfer_ctrl(struct qcom_qspi *ctrl) +{ + u32 pio_xfer_ctrl; + + pio_xfer_ctrl = readl(ctrl->base + PIO_XFER_CTRL); + pio_xfer_ctrl &= ~REQUEST_COUNT_MSK; + pio_xfer_ctrl |= ctrl->xfer.rem_bytes; + writel(pio_xfer_ctrl, ctrl->base + PIO_XFER_CTRL); +} + +static void qcom_qspi_pio_xfer(struct qcom_qspi *ctrl) +{ + u32 ints; + + qcom_qspi_pio_xfer_cfg(ctrl); + + /* Ack any previous interrupts that might be hanging around */ + writel(QSPI_ALL_IRQS, ctrl->base + MSTR_INT_STATUS); + + /* Setup new interrupts */ + if (ctrl->xfer.dir == QSPI_WRITE) + ints = QSPI_ERR_IRQS | WR_FIFO_EMPTY; + else + ints = QSPI_ERR_IRQS | RESP_FIFO_RDY; + writel(ints, ctrl->base + MSTR_INT_EN); + + /* Kick off the transfer */ + qcom_qspi_pio_xfer_ctrl(ctrl); +} + +static void qcom_qspi_handle_err(struct spi_master *master, + struct spi_message *msg) +{ + struct qcom_qspi *ctrl = spi_master_get_devdata(master); + unsigned long flags; + + spin_lock_irqsave(&ctrl->lock, flags); + writel(0, ctrl->base + MSTR_INT_EN); + ctrl->xfer.rem_bytes = 0; + spin_unlock_irqrestore(&ctrl->lock, flags); +} + +static int qcom_qspi_transfer_one(struct spi_master *master, + struct spi_device *slv, + struct spi_transfer *xfer) +{ + struct qcom_qspi *ctrl = spi_master_get_devdata(master); + int ret; + unsigned long speed_hz; + unsigned long flags; + + speed_hz = slv->max_speed_hz; + if (xfer->speed_hz) + speed_hz = xfer->speed_hz; + + /* In regular operation (SBL_EN=1) core must be 4x transfer clock */ + ret = clk_set_rate(ctrl->clks[QSPI_CLK_CORE].clk, speed_hz * 4); + if (ret) { + dev_err(ctrl->dev, "Failed to set core clk %d\n", ret); + return ret; + } + + spin_lock_irqsave(&ctrl->lock, flags); + + /* We are half duplex, so either rx or tx will be set */ + if (xfer->rx_buf) { + ctrl->xfer.dir = QSPI_READ; + ctrl->xfer.buswidth = xfer->rx_nbits; + ctrl->xfer.rx_buf = xfer->rx_buf; + } else { + ctrl->xfer.dir = QSPI_WRITE; + ctrl->xfer.buswidth = xfer->tx_nbits; + ctrl->xfer.tx_buf = xfer->tx_buf; + } + ctrl->xfer.is_last = list_is_last(&xfer->transfer_list, + &master->cur_msg->transfers); + ctrl->xfer.rem_bytes = xfer->len; + qcom_qspi_pio_xfer(ctrl); + + spin_unlock_irqrestore(&ctrl->lock, flags); + + /* We'll call spi_finalize_current_transfer() when done */ + return 1; +} + +static int qcom_qspi_prepare_message(struct spi_master *master, + struct spi_message *message) +{ + u32 mstr_cfg; + struct qcom_qspi *ctrl; + int tx_data_oe_delay = 1; + int tx_data_delay = 1; + unsigned long flags; + + ctrl = spi_master_get_devdata(master); + spin_lock_irqsave(&ctrl->lock, flags); + + mstr_cfg = readl(ctrl->base + MSTR_CONFIG); + mstr_cfg &= ~CHIP_SELECT_NUM; + if (message->spi->chip_select) + mstr_cfg |= CHIP_SELECT_NUM; + + mstr_cfg |= FB_CLK_EN | PIN_WPN | PIN_HOLDN | SBL_EN | FULL_CYCLE_MODE; + mstr_cfg &= ~(SPI_MODE_MSK | TX_DATA_OE_DELAY_MSK | TX_DATA_DELAY_MSK); + mstr_cfg |= message->spi->mode << SPI_MODE_SHFT; + mstr_cfg |= tx_data_oe_delay << TX_DATA_OE_DELAY_SHFT; + mstr_cfg |= tx_data_delay << TX_DATA_DELAY_SHFT; + mstr_cfg &= ~DMA_ENABLE; + + writel(mstr_cfg, ctrl->base + MSTR_CONFIG); + spin_unlock_irqrestore(&ctrl->lock, flags); + + return 0; +} + +static irqreturn_t pio_read(struct qcom_qspi *ctrl) +{ + u32 rd_fifo_status; + u32 rd_fifo; + unsigned int wr_cnts; + unsigned int bytes_to_read; + unsigned int words_to_read; + u32 *word_buf; + u8 *byte_buf; + int i; + + rd_fifo_status = readl(ctrl->base + RD_FIFO_STATUS); + + if (!(rd_fifo_status & FIFO_RDY)) { + dev_dbg(ctrl->dev, "Spurious IRQ %#x\n", rd_fifo_status); + return IRQ_NONE; + } + + wr_cnts = (rd_fifo_status & WR_CNTS_MSK) >> WR_CNTS_SHFT; + wr_cnts = min(wr_cnts, ctrl->xfer.rem_bytes); + + words_to_read = wr_cnts / QSPI_BYTES_PER_WORD; + bytes_to_read = wr_cnts % QSPI_BYTES_PER_WORD; + + if (words_to_read) { + word_buf = ctrl->xfer.rx_buf; + ctrl->xfer.rem_bytes -= words_to_read * QSPI_BYTES_PER_WORD; + ioread32_rep(ctrl->base + RD_FIFO, word_buf, words_to_read); + ctrl->xfer.rx_buf = word_buf + words_to_read; + } + + if (bytes_to_read) { + byte_buf = ctrl->xfer.rx_buf; + rd_fifo = readl(ctrl->base + RD_FIFO); + ctrl->xfer.rem_bytes -= bytes_to_read; + for (i = 0; i < bytes_to_read; i++) + *byte_buf++ = rd_fifo >> (i * BITS_PER_BYTE); + ctrl->xfer.rx_buf = byte_buf; + } + + return IRQ_HANDLED; +} + +static irqreturn_t pio_write(struct qcom_qspi *ctrl) +{ + const void *xfer_buf = ctrl->xfer.tx_buf; + const int *word_buf; + const char *byte_buf; + unsigned int wr_fifo_bytes; + unsigned int wr_fifo_words; + unsigned int wr_size; + unsigned int rem_words; + + wr_fifo_bytes = readl(ctrl->base + PIO_XFER_STATUS); + wr_fifo_bytes >>= WR_FIFO_BYTES_SHFT; + + if (ctrl->xfer.rem_bytes < QSPI_BYTES_PER_WORD) { + /* Process the last 1-3 bytes */ + wr_size = min(wr_fifo_bytes, ctrl->xfer.rem_bytes); + ctrl->xfer.rem_bytes -= wr_size; + + byte_buf = xfer_buf; + while (wr_size--) + writel(*byte_buf++, + ctrl->base + PIO_DATAOUT_1B); + ctrl->xfer.tx_buf = byte_buf; + } else { + /* + * Process all the whole words; to keep things simple we'll + * just wait for the next interrupt to handle the last 1-3 + * bytes if we don't have an even number of words. + */ + rem_words = ctrl->xfer.rem_bytes / QSPI_BYTES_PER_WORD; + wr_fifo_words = wr_fifo_bytes / QSPI_BYTES_PER_WORD; + + wr_size = min(rem_words, wr_fifo_words); + ctrl->xfer.rem_bytes -= wr_size * QSPI_BYTES_PER_WORD; + + word_buf = xfer_buf; + iowrite32_rep(ctrl->base + PIO_DATAOUT_4B, word_buf, wr_size); + ctrl->xfer.tx_buf = word_buf + wr_size; + + } + + return IRQ_HANDLED; +} + +static irqreturn_t qcom_qspi_irq(int irq, void *dev_id) +{ + u32 int_status; + struct qcom_qspi *ctrl = dev_id; + irqreturn_t ret = IRQ_NONE; + unsigned long flags; + + spin_lock_irqsave(&ctrl->lock, flags); + + int_status = readl(ctrl->base + MSTR_INT_STATUS); + writel(int_status, ctrl->base + MSTR_INT_STATUS); + + if (ctrl->xfer.dir == QSPI_WRITE) { + if (int_status & WR_FIFO_EMPTY) + ret = pio_write(ctrl); + } else { + if (int_status & RESP_FIFO_RDY) + ret = pio_read(ctrl); + } + + if (int_status & QSPI_ERR_IRQS) { + if (int_status & RESP_FIFO_UNDERRUN) + dev_err(ctrl->dev, "IRQ error: FIFO underrun\n"); + if (int_status & WR_FIFO_OVERRUN) + dev_err(ctrl->dev, "IRQ error: FIFO overrun\n"); + if (int_status & HRESP_FROM_NOC_ERR) + dev_err(ctrl->dev, "IRQ error: NOC response error\n"); + ret = IRQ_HANDLED; + } + + if (!ctrl->xfer.rem_bytes) { + writel(0, ctrl->base + MSTR_INT_EN); + spi_finalize_current_transfer(dev_get_drvdata(ctrl->dev)); + } + + spin_unlock_irqrestore(&ctrl->lock, flags); + return ret; +} + +static int qcom_qspi_probe(struct platform_device *pdev) +{ + int ret; + struct device *dev; + struct resource *res; + struct spi_master *master; + struct qcom_qspi *ctrl; + + dev = &pdev->dev; + + master = spi_alloc_master(dev, sizeof(*ctrl)); + if (!master) + return -ENOMEM; + + platform_set_drvdata(pdev, master); + + ctrl = spi_master_get_devdata(master); + + spin_lock_init(&ctrl->lock); + ctrl->dev = dev; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ctrl->base = devm_ioremap_resource(dev, res); + if (IS_ERR(ctrl->base)) { + ret = PTR_ERR(ctrl->base); + goto exit_probe_master_put; + } + + ctrl->clks[QSPI_CLK_CORE].id = "core"; + ctrl->clks[QSPI_CLK_IFACE].id = "iface"; + ret = devm_clk_bulk_get(dev, QSPI_NUM_CLKS, ctrl->clks); + if (ret) + goto exit_probe_master_put; + + ret = platform_get_irq(pdev, 0); + if (ret < 0) { + dev_err(dev, "Failed to get irq %d\n", ret); + goto exit_probe_master_put; + } + ret = devm_request_irq(dev, ret, qcom_qspi_irq, + IRQF_TRIGGER_HIGH, dev_name(dev), ctrl); + if (ret) { + dev_err(dev, "Failed to request irq %d\n", ret); + goto exit_probe_master_put; + } + + master->max_speed_hz = 300000000; + master->num_chipselect = QSPI_NUM_CS; + master->bus_num = -1; + master->dev.of_node = pdev->dev.of_node; + master->mode_bits = SPI_MODE_0 | + SPI_TX_DUAL | SPI_RX_DUAL | + SPI_TX_QUAD | SPI_RX_QUAD; + master->flags = SPI_MASTER_HALF_DUPLEX; + master->prepare_message = qcom_qspi_prepare_message; + master->transfer_one = qcom_qspi_transfer_one; + master->handle_err = qcom_qspi_handle_err; + master->auto_runtime_pm = true; + + pm_runtime_enable(dev); + + ret = spi_register_master(master); + if (!ret) + return 0; + + pm_runtime_disable(dev); + +exit_probe_master_put: + spi_master_put(master); + + return ret; +} + +static int qcom_qspi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + + /* Unregister _before_ disabling pm_runtime() so we stop transfers */ + spi_unregister_master(master); + + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static int __maybe_unused qcom_qspi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct qcom_qspi *ctrl = spi_master_get_devdata(master); + + clk_bulk_disable_unprepare(QSPI_NUM_CLKS, ctrl->clks); + + return 0; +} + +static int __maybe_unused qcom_qspi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct qcom_qspi *ctrl = spi_master_get_devdata(master); + + return clk_bulk_prepare_enable(QSPI_NUM_CLKS, ctrl->clks); +} + +static int __maybe_unused qcom_qspi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + ret = pm_runtime_force_suspend(dev); + if (ret) + spi_master_resume(master); + + return ret; +} + +static int __maybe_unused qcom_qspi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_force_resume(dev); + if (ret) + return ret; + + ret = spi_master_resume(master); + if (ret) + pm_runtime_force_suspend(dev); + + return ret; +} + +static const struct dev_pm_ops qcom_qspi_dev_pm_ops = { + SET_RUNTIME_PM_OPS(qcom_qspi_runtime_suspend, + qcom_qspi_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(qcom_qspi_suspend, qcom_qspi_resume) +}; + +static const struct of_device_id qcom_qspi_dt_match[] = { + { .compatible = "qcom,qspi-v1", }, + { } +}; +MODULE_DEVICE_TABLE(of, qcom_qspi_dt_match); + +static struct platform_driver qcom_qspi_driver = { + .driver = { + .name = "qcom_qspi", + .pm = &qcom_qspi_dev_pm_ops, + .of_match_table = qcom_qspi_dt_match, + }, + .probe = qcom_qspi_probe, + .remove = qcom_qspi_remove, +}; +module_platform_driver(qcom_qspi_driver); + +MODULE_DESCRIPTION("SPI driver for QSPI cores"); +MODULE_LICENSE("GPL v2"); |