/* * Driver for Broadcom BRCMSTB, NSP, NS2, Cygnus SPI Controllers * * Copyright 2016 Broadcom * * 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 (the "GPL"). * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License version 2 (GPLv2) for more details. * * You should have received a copy of the GNU General Public License * version 2 (GPLv2) along with this source code. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "spi-bcm-qspi.h" #define DRIVER_NAME "bcm_qspi" /* MSPI register offsets */ #define MSPI_SPCR0_LSB 0x000 #define MSPI_SPCR0_MSB 0x004 #define MSPI_SPCR1_LSB 0x008 #define MSPI_SPCR1_MSB 0x00c #define MSPI_NEWQP 0x010 #define MSPI_ENDQP 0x014 #define MSPI_SPCR2 0x018 #define MSPI_MSPI_STATUS 0x020 #define MSPI_CPTQP 0x024 #define MSPI_SPCR3 0x028 #define MSPI_TXRAM 0x040 #define MSPI_RXRAM 0x0c0 #define MSPI_CDRAM 0x140 #define MSPI_WRITE_LOCK 0x180 #define MSPI_MASTER_BIT BIT(7) #define MSPI_NUM_CDRAM 16 #define MSPI_CDRAM_CONT_BIT BIT(7) #define MSPI_CDRAM_BITSE_BIT BIT(6) #define MSPI_CDRAM_PCS 0xf #define MSPI_SPCR2_SPE BIT(6) #define MSPI_SPCR2_CONT_AFTER_CMD BIT(7) #define MSPI_MSPI_STATUS_SPIF BIT(0) #define INTR_BASE_BIT_SHIFT 0x02 #define INTR_COUNT 0x07 #define NUM_CHIPSELECT 4 #define QSPI_SPBR_MIN 8U #define QSPI_SPBR_MAX 255U #define OPCODE_DIOR 0xBB #define OPCODE_QIOR 0xEB #define OPCODE_DIOR_4B 0xBC #define OPCODE_QIOR_4B 0xEC #define MAX_CMD_SIZE 6 #define ADDR_4MB_MASK GENMASK(22, 0) /* stop at end of transfer, no other reason */ #define TRANS_STATUS_BREAK_NONE 0 /* stop at end of spi_message */ #define TRANS_STATUS_BREAK_EOM 1 /* stop at end of spi_transfer if delay */ #define TRANS_STATUS_BREAK_DELAY 2 /* stop at end of spi_transfer if cs_change */ #define TRANS_STATUS_BREAK_CS_CHANGE 4 /* stop if we run out of bytes */ #define TRANS_STATUS_BREAK_NO_BYTES 8 /* events that make us stop filling TX slots */ #define TRANS_STATUS_BREAK_TX (TRANS_STATUS_BREAK_EOM | \ TRANS_STATUS_BREAK_DELAY | \ TRANS_STATUS_BREAK_CS_CHANGE) /* events that make us deassert CS */ #define TRANS_STATUS_BREAK_DESELECT (TRANS_STATUS_BREAK_EOM | \ TRANS_STATUS_BREAK_CS_CHANGE) struct bcm_qspi_parms { u32 speed_hz; u8 mode; u8 bits_per_word; }; enum base_type { MSPI, CHIP_SELECT, BASEMAX, }; struct bcm_qspi_irq { const char *irq_name; const irq_handler_t irq_handler; u32 mask; }; struct bcm_qspi_dev_id { const struct bcm_qspi_irq *irqp; void *dev; }; struct qspi_trans { struct spi_transfer *trans; int byte; }; struct bcm_qspi { struct platform_device *pdev; struct spi_master *master; struct clk *clk; u32 base_clk; u32 max_speed_hz; void __iomem *base[BASEMAX]; struct bcm_qspi_parms last_parms; struct qspi_trans trans_pos; int curr_cs; u32 s3_strap_override_ctrl; bool big_endian; int num_irqs; struct bcm_qspi_dev_id *dev_ids; struct completion mspi_done; }; /* Read qspi controller register*/ static inline u32 bcm_qspi_read(struct bcm_qspi *qspi, enum base_type type, unsigned int offset) { return bcm_qspi_readl(qspi->big_endian, qspi->base[type] + offset); } /* Write qspi controller register*/ static inline void bcm_qspi_write(struct bcm_qspi *qspi, enum base_type type, unsigned int offset, unsigned int data) { bcm_qspi_writel(qspi->big_endian, data, qspi->base[type] + offset); } static void bcm_qspi_chip_select(struct bcm_qspi *qspi, int cs) { u32 data = 0; if (qspi->curr_cs == cs) return; if (qspi->base[CHIP_SELECT]) { data = bcm_qspi_read(qspi, CHIP_SELECT, 0); data = (data & ~0xff) | (1 << cs); bcm_qspi_write(qspi, CHIP_SELECT, 0, data); usleep_range(10, 20); } qspi->curr_cs = cs; } /* MSPI helpers */ static void bcm_qspi_hw_set_parms(struct bcm_qspi *qspi, const struct bcm_qspi_parms *xp) { u32 spcr, spbr = 0; if (xp->speed_hz) spbr = qspi->base_clk / (2 * xp->speed_hz); spcr = clamp_val(spbr, QSPI_SPBR_MIN, QSPI_SPBR_MAX); bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_LSB, spcr); spcr = MSPI_MASTER_BIT; /* for 16 bit the data should be zero */ if (xp->bits_per_word != 16) spcr |= xp->bits_per_word << 2; spcr |= xp->mode & 3; bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_MSB, spcr); qspi->last_parms = *xp; } static void bcm_qspi_update_parms(struct bcm_qspi *qspi, struct spi_device *spi, struct spi_transfer *trans) { struct bcm_qspi_parms xp; xp.speed_hz = trans->speed_hz; xp.bits_per_word = trans->bits_per_word; xp.mode = spi->mode; bcm_qspi_hw_set_parms(qspi, &xp); } static int bcm_qspi_setup(struct spi_device *spi) { struct bcm_qspi_parms *xp; if (spi->bits_per_word > 16) return -EINVAL; xp = spi_get_ctldata(spi); if (!xp) { xp = kzalloc(sizeof(*xp), GFP_KERNEL); if (!xp) return -ENOMEM; spi_set_ctldata(spi, xp); } xp->speed_hz = spi->max_speed_hz; xp->mode = spi->mode; if (spi->bits_per_word) xp->bits_per_word = spi->bits_per_word; else xp->bits_per_word = 8; return 0; } static int update_qspi_trans_byte_count(struct bcm_qspi *qspi, struct qspi_trans *qt, int flags) { int ret = TRANS_STATUS_BREAK_NONE; /* count the last transferred bytes */ if (qt->trans->bits_per_word <= 8) qt->byte++; else qt->byte += 2; if (qt->byte >= qt->trans->len) { /* we're at the end of the spi_transfer */ /* in TX mode, need to pause for a delay or CS change */ if (qt->trans->delay_usecs && (flags & TRANS_STATUS_BREAK_DELAY)) ret |= TRANS_STATUS_BREAK_DELAY; if (qt->trans->cs_change && (flags & TRANS_STATUS_BREAK_CS_CHANGE)) ret |= TRANS_STATUS_BREAK_CS_CHANGE; if (ret) goto done; dev_dbg(&qspi->pdev->dev, "advance msg exit\n"); if (spi_transfer_is_last(qspi->master, qt->trans)) ret = TRANS_STATUS_BREAK_EOM; else ret = TRANS_STATUS_BREAK_NO_BYTES; qt->trans = NULL; } done: dev_dbg(&qspi->pdev->dev, "trans %p len %d byte %d ret %x\n", qt->trans, qt->trans ? qt->trans->len : 0, qt->byte, ret); return ret; } static inline u8 read_rxram_slot_u8(struct bcm_qspi *qspi, int slot) { u32 slot_offset = MSPI_RXRAM + (slot << 3) + 0x4; /* mask out reserved bits */ return bcm_qspi_read(qspi, MSPI, slot_offset) & 0xff; } static inline u16 read_rxram_slot_u16(struct bcm_qspi *qspi, int slot) { u32 reg_offset = MSPI_RXRAM; u32 lsb_offset = reg_offset + (slot << 3) + 0x4; u32 msb_offset = reg_offset + (slot << 3); return (bcm_qspi_read(qspi, MSPI, lsb_offset) & 0xff) | ((bcm_qspi_read(qspi, MSPI, msb_offset) & 0xff) << 8); } static void read_from_hw(struct bcm_qspi *qspi, int slots) { struct qspi_trans tp; int slot; if (slots > MSPI_NUM_CDRAM) { /* should never happen */ dev_err(&qspi->pdev->dev, "%s: too many slots!\n", __func__); return; } tp = qspi->trans_pos; for (slot = 0; slot < slots; slot++) { if (tp.trans->bits_per_word <= 8) { u8 *buf = tp.trans->rx_buf; if (buf) buf[tp.byte] = read_rxram_slot_u8(qspi, slot); dev_dbg(&qspi->pdev->dev, "RD %02x\n", buf ? buf[tp.byte] : 0xff); } else { u16 *buf = tp.trans->rx_buf; if (buf) buf[tp.byte / 2] = read_rxram_slot_u16(qspi, slot); dev_dbg(&qspi->pdev->dev, "RD %04x\n", buf ? buf[tp.byte] : 0xffff); } update_qspi_trans_byte_count(qspi, &tp, TRANS_STATUS_BREAK_NONE); } qspi->trans_pos = tp; } static inline void write_txram_slot_u8(struct bcm_qspi *qspi, int slot, u8 val) { u32 reg_offset = MSPI_TXRAM + (slot << 3); /* mask out reserved bits */ bcm_qspi_write(qspi, MSPI, reg_offset, val); } static inline void write_txram_slot_u16(struct bcm_qspi *qspi, int slot, u16 val) { u32 reg_offset = MSPI_TXRAM; u32 msb_offset = reg_offset + (slot << 3); u32 lsb_offset = reg_offset + (slot << 3) + 0x4; bcm_qspi_write(qspi, MSPI, msb_offset, (val >> 8)); bcm_qspi_write(qspi, MSPI, lsb_offset, (val & 0xff)); } static inline u32 read_cdram_slot(struct bcm_qspi *qspi, int slot) { return bcm_qspi_read(qspi, MSPI, MSPI_CDRAM + (slot << 2)); } static inline void write_cdram_slot(struct bcm_qspi *qspi, int slot, u32 val) { bcm_qspi_write(qspi, MSPI, (MSPI_CDRAM + (slot << 2)), val); } /* Return number of slots written */ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi) { struct qspi_trans tp; int slot = 0, tstatus = 0; u32 mspi_cdram = 0; tp = qspi->trans_pos; bcm_qspi_update_parms(qspi, spi, tp.trans); /* Run until end of transfer or reached the max data */ while (!tstatus && slot < MSPI_NUM_CDRAM) { if (tp.trans->bits_per_word <= 8) { const u8 *buf = tp.trans->tx_buf; u8 val = buf ? buf[tp.byte] : 0xff; write_txram_slot_u8(qspi, slot, val); dev_dbg(&qspi->pdev->dev, "WR %02x\n", val); } else { const u16 *buf = tp.trans->tx_buf; u16 val = buf ? buf[tp.byte / 2] : 0xffff; write_txram_slot_u16(qspi, slot, val); dev_dbg(&qspi->pdev->dev, "WR %04x\n", val); } mspi_cdram = MSPI_CDRAM_CONT_BIT; mspi_cdram |= (~(1 << spi->chip_select) & MSPI_CDRAM_PCS); mspi_cdram |= ((tp.trans->bits_per_word <= 8) ? 0 : MSPI_CDRAM_BITSE_BIT); write_cdram_slot(qspi, slot, mspi_cdram); tstatus = update_qspi_trans_byte_count(qspi, &tp, TRANS_STATUS_BREAK_TX); slot++; } if (!slot) { dev_err(&qspi->pdev->dev, "%s: no data to send?", __func__); goto done; } dev_dbg(&qspi->pdev->dev, "submitting %d slots\n", slot); bcm_qspi_write(qspi, MSPI, MSPI_NEWQP, 0); bcm_qspi_write(qspi, MSPI, MSPI_ENDQP, slot - 1); if (tstatus & TRANS_STATUS_BREAK_DESELECT) { mspi_cdram = read_cdram_slot(qspi, slot - 1) & ~MSPI_CDRAM_CONT_BIT; write_cdram_slot(qspi, slot - 1, mspi_cdram); } /* Must flush previous writes before starting MSPI operation */ mb(); /* Set cont | spe | spifie */ bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0xe0); done: return slot; } static int bcm_qspi_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *trans) { struct bcm_qspi *qspi = spi_master_get_devdata(master); int slots; unsigned long timeo = msecs_to_jiffies(100); bcm_qspi_chip_select(qspi, spi->chip_select); qspi->trans_pos.trans = trans; qspi->trans_pos.byte = 0; while (qspi->trans_pos.byte < trans->len) { reinit_completion(&qspi->mspi_done); slots = write_to_hw(qspi, spi); if (!wait_for_completion_timeout(&qspi->mspi_done, timeo)) { dev_err(&qspi->pdev->dev, "timeout waiting for MSPI\n"); return -ETIMEDOUT; } read_from_hw(qspi, slots); } return 0; } static void bcm_qspi_cleanup(struct spi_device *spi) { struct bcm_qspi_parms *xp = spi_get_ctldata(spi); kfree(xp); } static irqreturn_t bcm_qspi_mspi_l2_isr(int irq, void *dev_id) { struct bcm_qspi_dev_id *qspi_dev_id = dev_id; struct bcm_qspi *qspi = qspi_dev_id->dev; u32 status = bcm_qspi_read(qspi, MSPI, MSPI_MSPI_STATUS); if (status & MSPI_MSPI_STATUS_SPIF) { /* clear interrupt */ status &= ~MSPI_MSPI_STATUS_SPIF; bcm_qspi_write(qspi, MSPI, MSPI_MSPI_STATUS, status); complete(&qspi->mspi_done); return IRQ_HANDLED; } else { return IRQ_NONE; } } static const struct bcm_qspi_irq qspi_irq_tab[] = { { .irq_name = "mspi_done", .irq_handler = bcm_qspi_mspi_l2_isr, .mask = INTR_MSPI_DONE_MASK, }, { .irq_name = "mspi_halted", .irq_handler = bcm_qspi_mspi_l2_isr, .mask = INTR_MSPI_HALTED_MASK, }, }; static void bcm_qspi_hw_init(struct bcm_qspi *qspi) { struct bcm_qspi_parms parms; bcm_qspi_write(qspi, MSPI, MSPI_SPCR1_LSB, 0); bcm_qspi_write(qspi, MSPI, MSPI_SPCR1_MSB, 0); bcm_qspi_write(qspi, MSPI, MSPI_NEWQP, 0); bcm_qspi_write(qspi, MSPI, MSPI_ENDQP, 0); bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0x20); parms.mode = SPI_MODE_3; parms.bits_per_word = 8; parms.speed_hz = qspi->max_speed_hz; bcm_qspi_hw_set_parms(qspi, &parms); } static void bcm_qspi_hw_uninit(struct bcm_qspi *qspi) { bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0); } static const struct of_device_id bcm_qspi_of_match[] = { { .compatible = "brcm,spi-bcm-qspi" }, {}, }; MODULE_DEVICE_TABLE(of, bcm_qspi_of_match); int bcm_qspi_probe(struct platform_device *pdev, struct bcm_qspi_soc_intc *soc) { struct device *dev = &pdev->dev; struct bcm_qspi *qspi; struct spi_master *master; struct resource *res; int irq, ret = 0, num_ints = 0; u32 val; const char *name = NULL; int num_irqs = ARRAY_SIZE(qspi_irq_tab); /* We only support device-tree instantiation */ if (!dev->of_node) return -ENODEV; if (!of_match_node(bcm_qspi_of_match, dev->of_node)) return -ENODEV; master = spi_alloc_master(dev, sizeof(struct bcm_qspi)); if (!master) { dev_err(dev, "error allocating spi_master\n"); return -ENOMEM; } qspi = spi_master_get_devdata(master); qspi->pdev = pdev; qspi->trans_pos.trans = NULL; qspi->trans_pos.byte = 0; qspi->master = master; master->bus_num = -1; master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_RX_DUAL | SPI_RX_QUAD; master->setup = bcm_qspi_setup; master->transfer_one = bcm_qspi_transfer_one; master->cleanup = bcm_qspi_cleanup; master->dev.of_node = dev->of_node; master->num_chipselect = NUM_CHIPSELECT; qspi->big_endian = of_device_is_big_endian(dev->of_node); if (!of_property_read_u32(dev->of_node, "num-cs", &val)) master->num_chipselect = val; res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "hif_mspi"); if (!res) res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mspi"); if (res) { qspi->base[MSPI] = devm_ioremap_resource(dev, res); if (IS_ERR(qspi->base[MSPI])) { ret = PTR_ERR(qspi->base[MSPI]); goto qspi_probe_err; } } else { goto qspi_probe_err; } res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cs_reg"); if (res) { qspi->base[CHIP_SELECT] = devm_ioremap_resource(dev, res); if (IS_ERR(qspi->base[CHIP_SELECT])) { ret = PTR_ERR(qspi->base[CHIP_SELECT]); goto qspi_probe_err; } } qspi->dev_ids = kcalloc(num_irqs, sizeof(struct bcm_qspi_dev_id), GFP_KERNEL); if (IS_ERR(qspi->dev_ids)) { ret = PTR_ERR(qspi->dev_ids); goto qspi_probe_err; } for (val = 0; val < num_irqs; val++) { irq = -1; name = qspi_irq_tab[val].irq_name; irq = platform_get_irq_byname(pdev, name); if (irq >= 0) { ret = devm_request_irq(&pdev->dev, irq, qspi_irq_tab[val].irq_handler, 0, name, &qspi->dev_ids[val]); if (ret < 0) { dev_err(&pdev->dev, "IRQ %s not found\n", name); goto qspi_probe_err; } qspi->dev_ids[val].dev = qspi; qspi->dev_ids[val].irqp = &qspi_irq_tab[val]; num_ints++; dev_dbg(&pdev->dev, "registered IRQ %s %d\n", qspi_irq_tab[val].irq_name, irq); } } if (!num_ints) { dev_err(&pdev->dev, "no IRQs registered, cannot init driver\n"); goto qspi_probe_err; } qspi->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(qspi->clk)) { dev_warn(dev, "unable to get clock\n"); goto qspi_probe_err; } ret = clk_prepare_enable(qspi->clk); if (ret) { dev_err(dev, "failed to prepare clock\n"); goto qspi_probe_err; } qspi->base_clk = clk_get_rate(qspi->clk); qspi->max_speed_hz = qspi->base_clk / (QSPI_SPBR_MIN * 2); bcm_qspi_hw_init(qspi); init_completion(&qspi->mspi_done); qspi->curr_cs = -1; platform_set_drvdata(pdev, qspi); ret = devm_spi_register_master(&pdev->dev, master); if (ret < 0) { dev_err(dev, "can't register master\n"); goto qspi_reg_err; } return 0; qspi_reg_err: bcm_qspi_hw_uninit(qspi); clk_disable_unprepare(qspi->clk); qspi_probe_err: spi_master_put(master); kfree(qspi->dev_ids); return ret; } /* probe function to be called by SoC specific platform driver probe */ EXPORT_SYMBOL_GPL(bcm_qspi_probe); int bcm_qspi_remove(struct platform_device *pdev) { struct bcm_qspi *qspi = platform_get_drvdata(pdev); platform_set_drvdata(pdev, NULL); bcm_qspi_hw_uninit(qspi); clk_disable_unprepare(qspi->clk); kfree(qspi->dev_ids); spi_unregister_master(qspi->master); return 0; } /* function to be called by SoC specific platform driver remove() */ EXPORT_SYMBOL_GPL(bcm_qspi_remove); #ifdef CONFIG_PM_SLEEP static int bcm_qspi_suspend(struct device *dev) { struct bcm_qspi *qspi = dev_get_drvdata(dev); spi_master_suspend(qspi->master); clk_disable(qspi->clk); bcm_qspi_hw_uninit(qspi); return 0; }; static int bcm_qspi_resume(struct device *dev) { struct bcm_qspi *qspi = dev_get_drvdata(dev); int ret = 0; bcm_qspi_hw_init(qspi); bcm_qspi_chip_select(qspi, qspi->curr_cs); ret = clk_enable(qspi->clk); if (!ret) spi_master_resume(qspi->master); return ret; } #endif /* CONFIG_PM_SLEEP */ const struct dev_pm_ops bcm_qspi_pm_ops = { .suspend = bcm_qspi_suspend, .resume = bcm_qspi_resume, }; /* pm_ops to be called by SoC specific platform driver */ EXPORT_SYMBOL_GPL(bcm_qspi_pm_ops); MODULE_AUTHOR("Kamal Dasu"); MODULE_DESCRIPTION("Broadcom QSPI driver"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:" DRIVER_NAME);