// 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) enum spi_m_cmd_opcode { CMD_NONE, CMD_XFER, CMD_CS, CMD_CANCEL, }; struct spi_geni_master { struct geni_se se; struct device *dev; u32 tx_fifo_depth; u32 fifo_width_bits; u32 tx_wm; unsigned long cur_speed_hz; unsigned int cur_bits_per_word; unsigned int tx_rem_bytes; unsigned int rx_rem_bytes; const struct spi_transfer *cur_xfer; struct completion xfer_done; unsigned int oversampling; spinlock_t lock; enum spi_m_cmd_opcode cur_mcmd; int irq; }; static int get_spi_clk_cfg(unsigned int speed_hz, struct spi_geni_master *mas, unsigned int *clk_idx, unsigned int *clk_div) { unsigned long sclk_freq; unsigned int actual_hz; struct geni_se *se = &mas->se; int ret; ret = geni_se_clk_freq_match(&mas->se, speed_hz * mas->oversampling, clk_idx, &sclk_freq, false); if (ret) { dev_err(mas->dev, "Failed(%d) to find src clk for %dHz\n", ret, speed_hz); return ret; } *clk_div = DIV_ROUND_UP(sclk_freq, mas->oversampling * speed_hz); actual_hz = sclk_freq / (mas->oversampling * *clk_div); dev_dbg(mas->dev, "req %u=>%u sclk %lu, idx %d, div %d\n", speed_hz, actual_hz, sclk_freq, *clk_idx, *clk_div); ret = clk_set_rate(se->clk, sclk_freq); if (ret) dev_err(mas->dev, "clk_set_rate failed %d\n", ret); return ret; } 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 time_left; struct geni_se *se = &mas->se; spin_lock_irq(&mas->lock); reinit_completion(&mas->xfer_done); mas->cur_mcmd = CMD_CANCEL; geni_se_cancel_m_cmd(se); writel(0, se->base + SE_GENI_TX_WATERMARK_REG); spin_unlock_irq(&mas->lock); time_left = wait_for_completion_timeout(&mas->xfer_done, HZ); if (time_left) return; spin_lock_irq(&mas->lock); reinit_completion(&mas->xfer_done); geni_se_abort_m_cmd(se); spin_unlock_irq(&mas->lock); time_left = wait_for_completion_timeout(&mas->xfer_done, HZ); if (!time_left) dev_err(mas->dev, "Failed to cancel/abort m_cmd\n"); } static void spi_geni_set_cs(struct spi_device *slv, bool set_flag) { struct spi_geni_master *mas = spi_master_get_devdata(slv->master); struct spi_master *spi = dev_get_drvdata(mas->dev); struct geni_se *se = &mas->se; unsigned long time_left; reinit_completion(&mas->xfer_done); pm_runtime_get_sync(mas->dev); if (!(slv->mode & SPI_CS_HIGH)) set_flag = !set_flag; mas->cur_mcmd = CMD_CS; if (set_flag) geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0); else geni_se_setup_m_cmd(se, SPI_CS_DEASSERT, 0); time_left = wait_for_completion_timeout(&mas->xfer_done, HZ); if (!time_left) handle_fifo_timeout(spi, NULL); pm_runtime_put(mas->dev); } static void spi_setup_word_len(struct spi_geni_master *mas, u16 mode, unsigned int bits_per_word) { unsigned int pack_words; bool msb_first = (mode & SPI_LSB_FIRST) ? false : true; struct geni_se *se = &mas->se; u32 word_len; word_len = readl(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->fifo_width_bits % bits_per_word)) pack_words = mas->fifo_width_bits / bits_per_word; else pack_words = 1; 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(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; u32 loopback_cfg, cpol, cpha, demux_output_inv; u32 demux_sel, clk_sel, m_clk_cfg, idx, div; int ret; loopback_cfg = readl(se->base + SE_SPI_LOOPBACK); cpol = readl(se->base + SE_SPI_CPOL); cpha = readl(se->base + SE_SPI_CPHA); demux_output_inv = 0; loopback_cfg &= ~LOOPBACK_MSK; cpol &= ~CPOL; cpha &= ~CPHA; if (spi_slv->mode & SPI_LOOP) loopback_cfg |= LOOPBACK_ENABLE; if (spi_slv->mode & SPI_CPOL) cpol |= CPOL; if (spi_slv->mode & SPI_CPHA) cpha |= CPHA; if (spi_slv->mode & SPI_CS_HIGH) demux_output_inv = BIT(spi_slv->chip_select); demux_sel = spi_slv->chip_select; mas->cur_speed_hz = spi_slv->max_speed_hz; mas->cur_bits_per_word = 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 %ld\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(loopback_cfg, se->base + SE_SPI_LOOPBACK); writel(demux_sel, se->base + SE_SPI_DEMUX_SEL); writel(cpha, se->base + SE_SPI_CPHA); writel(cpol, se->base + SE_SPI_CPOL); writel(demux_output_inv, se->base + SE_SPI_DEMUX_OUTPUT_INV); writel(clk_sel, se->base + SE_GENI_CLK_SEL); writel(m_clk_cfg, se->base + GENI_SER_M_CLK_CFG); return 0; } static int spi_geni_prepare_message(struct spi_master *spi, struct spi_message *spi_msg) { int ret; struct spi_geni_master *mas = spi_master_get_devdata(spi); struct geni_se *se = &mas->se; geni_se_select_mode(se, GENI_SE_FIFO); ret = setup_fifo_params(spi_msg->spi, spi); if (ret) dev_err(mas->dev, "Couldn't select mode %d\n", ret); return ret; } static int spi_geni_init(struct spi_geni_master *mas) { struct geni_se *se = &mas->se; unsigned int proto, major, minor, ver; pm_runtime_get_sync(mas->dev); proto = geni_se_read_proto(se); if (proto != GENI_SE_SPI) { dev_err(mas->dev, "Invalid proto %d\n", proto); pm_runtime_put(mas->dev); return -ENXIO; } mas->tx_fifo_depth = geni_se_get_tx_fifo_depth(se); /* Width of Tx and Rx FIFO is same */ mas->fifo_width_bits = geni_se_get_tx_fifo_width(se); /* * Hardware programming guide suggests to configure * RX FIFO RFR level to fifo_depth-2. */ geni_se_init(se, 0x0, mas->tx_fifo_depth - 2); /* Transmit an entire FIFO worth of data per IRQ */ mas->tx_wm = 1; ver = geni_se_get_qup_hw_version(se); major = GENI_SE_VERSION_MAJOR(ver); minor = GENI_SE_VERSION_MINOR(ver); if (major == 1 && minor == 0) mas->oversampling = 2; else mas->oversampling = 1; pm_runtime_put(mas->dev); 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 spi_tx_cfg, len; struct geni_se *se = &mas->se; spi_tx_cfg = readl(se->base + SE_SPI_TRANS_CFG); if (xfer->bits_per_word != mas->cur_bits_per_word) { spi_setup_word_len(mas, mode, xfer->bits_per_word); mas->cur_bits_per_word = xfer->bits_per_word; } /* Speed and bits per word can be overridden per transfer */ if (xfer->speed_hz != mas->cur_speed_hz) { int ret; u32 clk_sel, m_clk_cfg; unsigned int idx, div; ret = get_spi_clk_cfg(xfer->speed_hz, mas, &idx, &div); if (ret) { dev_err(mas->dev, "Err setting clks:%d\n", ret); return; } /* * SPI core clock gets configured with the requested frequency * or the frequency closer to the requested frequency. * For that reason requested frequency is stored in the * cur_speed_hz and referred in the consecutive transfer instead * of calling clk_get_rate() API. */ mas->cur_speed_hz = xfer->speed_hz; clk_sel = idx & CLK_SEL_MSK; m_clk_cfg = (div << CLK_DIV_SHFT) | SER_CLK_EN; writel(clk_sel, se->base + SE_GENI_CLK_SEL); writel(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_bits_per_word % MIN_WORD_LEN)) len = xfer->len * BITS_PER_BYTE / mas->cur_bits_per_word; else len = xfer->len / (mas->cur_bits_per_word / BITS_PER_BYTE + 1); len &= TRANS_LEN_MSK; mas->cur_xfer = xfer; if (m_cmd & SPI_TX_ONLY) { mas->tx_rem_bytes = xfer->len; writel(len, se->base + SE_SPI_TX_TRANS_LEN); } if (m_cmd & SPI_RX_ONLY) { writel(len, se->base + SE_SPI_RX_TRANS_LEN); mas->rx_rem_bytes = xfer->len; } writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG); mas->cur_mcmd = CMD_XFER; geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION); /* * TX_WATERMARK_REG should be set after SPI configuration and * setting up GENI SE engine, as driver starts data transfer * for the watermark interrupt. */ if (m_cmd & SPI_TX_ONLY) writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG); } 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); /* Terminate and return success for 0 byte length transfer */ if (!xfer->len) return 0; setup_fifo_xfer(xfer, mas, slv->mode, spi); return 1; } static unsigned int geni_byte_per_fifo_word(struct spi_geni_master *mas) { /* * Calculate how many bytes we'll put in each FIFO word. If the * transfer words don't pack cleanly into a FIFO word we'll just put * one transfer word in each FIFO word. If they do pack we'll pack 'em. */ if (mas->fifo_width_bits % mas->cur_bits_per_word) return roundup_pow_of_two(DIV_ROUND_UP(mas->cur_bits_per_word, BITS_PER_BYTE)); return mas->fifo_width_bits / BITS_PER_BYTE; } static void geni_spi_handle_tx(struct spi_geni_master *mas) { struct geni_se *se = &mas->se; unsigned int max_bytes; const u8 *tx_buf; unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas); unsigned int i = 0; max_bytes = (mas->tx_fifo_depth - mas->tx_wm) * bytes_per_fifo_word; if (mas->tx_rem_bytes < max_bytes) max_bytes = mas->tx_rem_bytes; tx_buf = mas->cur_xfer->tx_buf + mas->cur_xfer->len - mas->tx_rem_bytes; while (i < max_bytes) { unsigned int j; unsigned int bytes_to_write; u32 fifo_word = 0; u8 *fifo_byte = (u8 *)&fifo_word; bytes_to_write = min(bytes_per_fifo_word, max_bytes - i); 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(0, se->base + SE_GENI_TX_WATERMARK_REG); } static void geni_spi_handle_rx(struct spi_geni_master *mas) { struct geni_se *se = &mas->se; u32 rx_fifo_status; unsigned int rx_bytes; unsigned int rx_last_byte_valid; u8 *rx_buf; unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas); unsigned int i = 0; rx_fifo_status = readl(se->base + SE_GENI_RX_FIFO_STATUS); rx_bytes = (rx_fifo_status & RX_FIFO_WC_MSK) * bytes_per_fifo_word; if (rx_fifo_status & RX_LAST) { rx_last_byte_valid = rx_fifo_status & RX_LAST_BYTE_VALID_MSK; rx_last_byte_valid >>= RX_LAST_BYTE_VALID_SHFT; if (rx_last_byte_valid && rx_last_byte_valid < 4) rx_bytes -= bytes_per_fifo_word - rx_last_byte_valid; } if (mas->rx_rem_bytes < rx_bytes) rx_bytes = mas->rx_rem_bytes; rx_buf = mas->cur_xfer->rx_buf + mas->cur_xfer->len - mas->rx_rem_bytes; while (i < rx_bytes) { u32 fifo_word = 0; u8 *fifo_byte = (u8 *)&fifo_word; unsigned int bytes_to_read; unsigned int j; bytes_to_read = min(bytes_per_fifo_word, rx_bytes - i); ioread32_rep(se->base + SE_GENI_RX_FIFOn, &fifo_word, 1); for (j = 0; j < bytes_to_read; 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; if (mas->cur_mcmd == CMD_NONE) return IRQ_NONE; spin_lock(&mas->lock); m_irq = readl(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) { if (mas->cur_mcmd == CMD_XFER) spi_finalize_current_transfer(spi); else if (mas->cur_mcmd == CMD_CS) complete(&mas->xfer_done); mas->cur_mcmd = CMD_NONE; /* * 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(0, se->base + SE_GENI_TX_WATERMARK_REG); dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n", mas->tx_rem_bytes, mas->cur_bits_per_word); } if (mas->rx_rem_bytes) dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n", mas->rx_rem_bytes, mas->cur_bits_per_word); } if ((m_irq & M_CMD_CANCEL_EN) || (m_irq & M_CMD_ABORT_EN)) { mas->cur_mcmd = CMD_NONE; complete(&mas->xfer_done); } writel(m_irq, se->base + SE_GENI_M_IRQ_CLEAR); spin_unlock(&mas->lock); return IRQ_HANDLED; } static int spi_geni_probe(struct platform_device *pdev) { int ret, irq; struct spi_master *spi; struct spi_geni_master *mas; void __iomem *base; struct clk *clk; struct device *dev = &pdev->dev; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(base)) return PTR_ERR(base); clk = devm_clk_get(dev, "se"); if (IS_ERR(clk)) return PTR_ERR(clk); spi = spi_alloc_master(dev, sizeof(*mas)); if (!spi) return -ENOMEM; platform_set_drvdata(pdev, spi); mas = spi_master_get_devdata(spi); mas->irq = irq; mas->dev = dev; mas->se.dev = dev; mas->se.wrapper = dev_get_drvdata(dev->parent); mas->se.base = base; mas->se.clk = clk; spi->bus_num = -1; spi->dev.of_node = dev->of_node; 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->max_speed_hz = 50000000; 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; spi->set_cs = spi_geni_set_cs; init_completion(&mas->xfer_done); spin_lock_init(&mas->lock); pm_runtime_enable(dev); ret = spi_geni_init(mas); if (ret) goto spi_geni_probe_runtime_disable; ret = request_irq(mas->irq, geni_spi_isr, 0, dev_name(dev), spi); if (ret) goto spi_geni_probe_runtime_disable; ret = spi_register_master(spi); if (ret) goto spi_geni_probe_free_irq; return 0; spi_geni_probe_free_irq: free_irq(mas->irq, spi); spi_geni_probe_runtime_disable: pm_runtime_disable(dev); spi_master_put(spi); return ret; } static int spi_geni_remove(struct platform_device *pdev) { struct spi_master *spi = platform_get_drvdata(pdev); struct spi_geni_master *mas = spi_master_get_devdata(spi); /* Unregister _before_ disabling pm_runtime() so we stop transfers */ spi_unregister_master(spi); free_irq(mas->irq, spi); 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 *mas = spi_master_get_devdata(spi); return geni_se_resources_off(&mas->se); } static int __maybe_unused spi_geni_runtime_resume(struct device *dev) { struct spi_master *spi = dev_get_drvdata(dev); struct spi_geni_master *mas = spi_master_get_devdata(spi); return geni_se_resources_on(&mas->se); } static int __maybe_unused spi_geni_suspend(struct device *dev) { struct spi_master *spi = dev_get_drvdata(dev); int ret; ret = spi_master_suspend(spi); if (ret) return ret; ret = pm_runtime_force_suspend(dev); if (ret) spi_master_resume(spi); return ret; } static int __maybe_unused spi_geni_resume(struct device *dev) { struct spi_master *spi = dev_get_drvdata(dev); int ret; ret = pm_runtime_force_resume(dev); if (ret) return ret; ret = spi_master_resume(spi); if (ret) pm_runtime_force_suspend(dev); return ret; } 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, spi_geni_resume) }; static const struct of_device_id spi_geni_dt_match[] = { { .compatible = "qcom,geni-spi" }, {} }; MODULE_DEVICE_TABLE(of, spi_geni_dt_match); 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");