// SPDX-License-Identifier: GPL-2.0-or-later /* * Freescale SPI controller driver. * * Maintainer: Kumar Gala * * Copyright (C) 2006 Polycom, Inc. * Copyright 2010 Freescale Semiconductor, Inc. * * CPM SPI and QE buffer descriptors mode support: * Copyright (c) 2009 MontaVista Software, Inc. * Author: Anton Vorontsov * * GRLIB support: * Copyright (c) 2012 Aeroflex Gaisler AB. * Author: Andreas Larsson */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_FSL_SOC #include #endif /* Specific to the MPC8306/MPC8309 */ #define IMMR_SPI_CS_OFFSET 0x14c #define SPI_BOOT_SEL_BIT 0x80000000 #include "spi-fsl-lib.h" #include "spi-fsl-cpm.h" #include "spi-fsl-spi.h" #define TYPE_FSL 0 #define TYPE_GRLIB 1 struct fsl_spi_match_data { int type; }; static struct fsl_spi_match_data of_fsl_spi_fsl_config = { .type = TYPE_FSL, }; static struct fsl_spi_match_data of_fsl_spi_grlib_config = { .type = TYPE_GRLIB, }; static const struct of_device_id of_fsl_spi_match[] = { { .compatible = "fsl,spi", .data = &of_fsl_spi_fsl_config, }, { .compatible = "aeroflexgaisler,spictrl", .data = &of_fsl_spi_grlib_config, }, {} }; MODULE_DEVICE_TABLE(of, of_fsl_spi_match); static int fsl_spi_get_type(struct device *dev) { const struct of_device_id *match; if (dev->of_node) { match = of_match_node(of_fsl_spi_match, dev->of_node); if (match && match->data) return ((struct fsl_spi_match_data *)match->data)->type; } return TYPE_FSL; } static void fsl_spi_change_mode(struct spi_device *spi) { struct mpc8xxx_spi *mspi = spi_controller_get_devdata(spi->controller); struct spi_mpc8xxx_cs *cs = spi->controller_state; struct fsl_spi_reg __iomem *reg_base = mspi->reg_base; __be32 __iomem *mode = ®_base->mode; unsigned long flags; if (cs->hw_mode == mpc8xxx_spi_read_reg(mode)) return; /* Turn off IRQs locally to minimize time that SPI is disabled. */ local_irq_save(flags); /* Turn off SPI unit prior changing mode */ mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE); /* When in CPM mode, we need to reinit tx and rx. */ if (mspi->flags & SPI_CPM_MODE) { fsl_spi_cpm_reinit_txrx(mspi); } mpc8xxx_spi_write_reg(mode, cs->hw_mode); local_irq_restore(flags); } static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift, int bits_per_word, int msb_first) { *rx_shift = 0; *tx_shift = 0; if (msb_first) { if (bits_per_word <= 8) { *rx_shift = 16; *tx_shift = 24; } else if (bits_per_word <= 16) { *rx_shift = 16; *tx_shift = 16; } } else { if (bits_per_word <= 8) *rx_shift = 8; } } static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift, int bits_per_word, int msb_first) { *rx_shift = 0; *tx_shift = 0; if (bits_per_word <= 16) { if (msb_first) { *rx_shift = 16; /* LSB in bit 16 */ *tx_shift = 32 - bits_per_word; /* MSB in bit 31 */ } else { *rx_shift = 16 - bits_per_word; /* MSB in bit 15 */ } } } static void mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs, struct spi_device *spi, struct mpc8xxx_spi *mpc8xxx_spi, int bits_per_word) { cs->rx_shift = 0; cs->tx_shift = 0; if (bits_per_word <= 8) { cs->get_rx = mpc8xxx_spi_rx_buf_u8; cs->get_tx = mpc8xxx_spi_tx_buf_u8; } else if (bits_per_word <= 16) { cs->get_rx = mpc8xxx_spi_rx_buf_u16; cs->get_tx = mpc8xxx_spi_tx_buf_u16; } else if (bits_per_word <= 32) { cs->get_rx = mpc8xxx_spi_rx_buf_u32; cs->get_tx = mpc8xxx_spi_tx_buf_u32; } if (mpc8xxx_spi->set_shifts) mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift, bits_per_word, !(spi->mode & SPI_LSB_FIRST)); mpc8xxx_spi->rx_shift = cs->rx_shift; mpc8xxx_spi->tx_shift = cs->tx_shift; mpc8xxx_spi->get_rx = cs->get_rx; mpc8xxx_spi->get_tx = cs->get_tx; } static int fsl_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) { struct mpc8xxx_spi *mpc8xxx_spi; int bits_per_word = 0; u8 pm; u32 hz = 0; struct spi_mpc8xxx_cs *cs = spi->controller_state; mpc8xxx_spi = spi_controller_get_devdata(spi->controller); if (t) { bits_per_word = t->bits_per_word; hz = t->speed_hz; } /* spi_transfer level calls that work per-word */ if (!bits_per_word) bits_per_word = spi->bits_per_word; if (!hz) hz = spi->max_speed_hz; if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) mspi_apply_cpu_mode_quirks(cs, spi, mpc8xxx_spi, bits_per_word); if (bits_per_word == 32) bits_per_word = 0; else bits_per_word = bits_per_word - 1; /* mask out bits we are going to set */ cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16 | SPMODE_PM(0xF)); cs->hw_mode |= SPMODE_LEN(bits_per_word); if ((mpc8xxx_spi->spibrg / hz) > 64) { cs->hw_mode |= SPMODE_DIV16; pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1; WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n", dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024); if (pm > 16) pm = 16; } else { pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1; } if (pm) pm--; cs->hw_mode |= SPMODE_PM(pm); fsl_spi_change_mode(spi); return 0; } static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi, struct spi_transfer *t, unsigned int len) { u32 word; struct fsl_spi_reg __iomem *reg_base = mspi->reg_base; mspi->count = len; /* enable rx ints */ mpc8xxx_spi_write_reg(®_base->mask, SPIM_NE); /* transmit word */ word = mspi->get_tx(mspi); mpc8xxx_spi_write_reg(®_base->transmit, word); return 0; } static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t) { struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(spi->controller); struct fsl_spi_reg __iomem *reg_base; unsigned int len = t->len; u8 bits_per_word; int ret; reg_base = mpc8xxx_spi->reg_base; bits_per_word = spi->bits_per_word; if (t->bits_per_word) bits_per_word = t->bits_per_word; if (bits_per_word > 8) len /= 2; if (bits_per_word > 16) len /= 2; mpc8xxx_spi->tx = t->tx_buf; mpc8xxx_spi->rx = t->rx_buf; reinit_completion(&mpc8xxx_spi->done); if (mpc8xxx_spi->flags & SPI_CPM_MODE) ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t); else ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len); if (ret) return ret; wait_for_completion(&mpc8xxx_spi->done); /* disable rx ints */ mpc8xxx_spi_write_reg(®_base->mask, 0); if (mpc8xxx_spi->flags & SPI_CPM_MODE) fsl_spi_cpm_bufs_complete(mpc8xxx_spi); return mpc8xxx_spi->count; } static int fsl_spi_prepare_message(struct spi_controller *ctlr, struct spi_message *m) { struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(ctlr); struct spi_transfer *t; struct spi_transfer *first; first = list_first_entry(&m->transfers, struct spi_transfer, transfer_list); /* * In CPU mode, optimize large byte transfers to use larger * bits_per_word values to reduce number of interrupts taken. * * Some glitches can appear on the SPI clock when the mode changes. * Check that there is no speed change during the transfer and set it up * now to change the mode without having a chip-select asserted. */ list_for_each_entry(t, &m->transfers, transfer_list) { if (t->speed_hz != first->speed_hz) { dev_err(&m->spi->dev, "speed_hz cannot change during message.\n"); return -EINVAL; } if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) { if (t->len < 256 || t->bits_per_word != 8) continue; if ((t->len & 3) == 0) t->bits_per_word = 32; else if ((t->len & 1) == 0) t->bits_per_word = 16; } else { /* * CPM/QE uses Little Endian for words > 8 * so transform 16 and 32 bits words into 8 bits * Unfortnatly that doesn't work for LSB so * reject these for now * Note: 32 bits word, LSB works iff * tfcr/rfcr is set to CPMFCR_GBL */ if (m->spi->mode & SPI_LSB_FIRST && t->bits_per_word > 8) return -EINVAL; if (t->bits_per_word == 16 || t->bits_per_word == 32) t->bits_per_word = 8; /* pretend its 8 bits */ if (t->bits_per_word == 8 && t->len >= 256 && (mpc8xxx_spi->flags & SPI_CPM1)) t->bits_per_word = 16; } } return fsl_spi_setup_transfer(m->spi, first); } static int fsl_spi_transfer_one(struct spi_controller *controller, struct spi_device *spi, struct spi_transfer *t) { int status; status = fsl_spi_setup_transfer(spi, t); if (status < 0) return status; if (t->len) status = fsl_spi_bufs(spi, t); if (status > 0) return -EMSGSIZE; return status; } static int fsl_spi_unprepare_message(struct spi_controller *controller, struct spi_message *msg) { return fsl_spi_setup_transfer(msg->spi, NULL); } static int fsl_spi_setup(struct spi_device *spi) { struct mpc8xxx_spi *mpc8xxx_spi; struct fsl_spi_reg __iomem *reg_base; bool initial_setup = false; int retval; u32 hw_mode; struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi); if (!spi->max_speed_hz) return -EINVAL; if (!cs) { cs = kzalloc(sizeof(*cs), GFP_KERNEL); if (!cs) return -ENOMEM; spi_set_ctldata(spi, cs); initial_setup = true; } mpc8xxx_spi = spi_controller_get_devdata(spi->controller); reg_base = mpc8xxx_spi->reg_base; hw_mode = cs->hw_mode; /* Save original settings */ cs->hw_mode = mpc8xxx_spi_read_reg(®_base->mode); /* mask out bits we are going to set */ cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH | SPMODE_REV | SPMODE_LOOP); if (spi->mode & SPI_CPHA) cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK; if (spi->mode & SPI_CPOL) cs->hw_mode |= SPMODE_CI_INACTIVEHIGH; if (!(spi->mode & SPI_LSB_FIRST)) cs->hw_mode |= SPMODE_REV; if (spi->mode & SPI_LOOP) cs->hw_mode |= SPMODE_LOOP; retval = fsl_spi_setup_transfer(spi, NULL); if (retval < 0) { cs->hw_mode = hw_mode; /* Restore settings */ if (initial_setup) kfree(cs); return retval; } return 0; } static void fsl_spi_cleanup(struct spi_device *spi) { struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi); kfree(cs); spi_set_ctldata(spi, NULL); } static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events) { struct fsl_spi_reg __iomem *reg_base = mspi->reg_base; /* We need handle RX first */ if (events & SPIE_NE) { u32 rx_data = mpc8xxx_spi_read_reg(®_base->receive); if (mspi->rx) mspi->get_rx(rx_data, mspi); } if ((events & SPIE_NF) == 0) /* spin until TX is done */ while (((events = mpc8xxx_spi_read_reg(®_base->event)) & SPIE_NF) == 0) cpu_relax(); /* Clear the events */ mpc8xxx_spi_write_reg(®_base->event, events); mspi->count -= 1; if (mspi->count) { u32 word = mspi->get_tx(mspi); mpc8xxx_spi_write_reg(®_base->transmit, word); } else { complete(&mspi->done); } } static irqreturn_t fsl_spi_irq(s32 irq, void *context_data) { struct mpc8xxx_spi *mspi = context_data; irqreturn_t ret = IRQ_NONE; u32 events; struct fsl_spi_reg __iomem *reg_base = mspi->reg_base; /* Get interrupt events(tx/rx) */ events = mpc8xxx_spi_read_reg(®_base->event); if (events) ret = IRQ_HANDLED; dev_dbg(mspi->dev, "%s: events %x\n", __func__, events); if (mspi->flags & SPI_CPM_MODE) fsl_spi_cpm_irq(mspi, events); else fsl_spi_cpu_irq(mspi, events); return ret; } static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on) { struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(spi->controller); struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base; u32 slvsel; u16 cs = spi_get_chipselect(spi, 0); if (cs < mpc8xxx_spi->native_chipselects) { slvsel = mpc8xxx_spi_read_reg(®_base->slvsel); slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs)); mpc8xxx_spi_write_reg(®_base->slvsel, slvsel); } } static void fsl_spi_grlib_probe(struct device *dev) { struct spi_controller *host = dev_get_drvdata(dev); struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host); struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base; int mbits; u32 capabilities; capabilities = mpc8xxx_spi_read_reg(®_base->cap); mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts; mbits = SPCAP_MAXWLEN(capabilities); if (mbits) mpc8xxx_spi->max_bits_per_word = mbits + 1; mpc8xxx_spi->native_chipselects = 0; if (SPCAP_SSEN(capabilities)) { mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities); mpc8xxx_spi_write_reg(®_base->slvsel, 0xffffffff); } host->num_chipselect = mpc8xxx_spi->native_chipselects; host->set_cs = fsl_spi_grlib_cs_control; } static void fsl_spi_cs_control(struct spi_device *spi, bool on) { struct device *dev = spi->dev.parent->parent; struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata); if (WARN_ON_ONCE(!pinfo->immr_spi_cs)) return; iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs); } static struct spi_controller *fsl_spi_probe(struct device *dev, struct resource *mem, unsigned int irq) { struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); struct spi_controller *host; struct mpc8xxx_spi *mpc8xxx_spi; struct fsl_spi_reg __iomem *reg_base; u32 regval; int ret = 0; host = spi_alloc_host(dev, sizeof(struct mpc8xxx_spi)); if (host == NULL) { ret = -ENOMEM; goto err; } dev_set_drvdata(dev, host); mpc8xxx_spi_probe(dev, mem, irq); host->setup = fsl_spi_setup; host->cleanup = fsl_spi_cleanup; host->prepare_message = fsl_spi_prepare_message; host->transfer_one = fsl_spi_transfer_one; host->unprepare_message = fsl_spi_unprepare_message; host->use_gpio_descriptors = true; host->set_cs = fsl_spi_cs_control; mpc8xxx_spi = spi_controller_get_devdata(host); mpc8xxx_spi->max_bits_per_word = 32; mpc8xxx_spi->type = fsl_spi_get_type(dev); ret = fsl_spi_cpm_init(mpc8xxx_spi); if (ret) goto err_cpm_init; mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem); if (IS_ERR(mpc8xxx_spi->reg_base)) { ret = PTR_ERR(mpc8xxx_spi->reg_base); goto err_probe; } if (mpc8xxx_spi->type == TYPE_GRLIB) fsl_spi_grlib_probe(dev); if (mpc8xxx_spi->flags & SPI_CPM_MODE) host->bits_per_word_mask = (SPI_BPW_RANGE_MASK(4, 8) | SPI_BPW_MASK(16) | SPI_BPW_MASK(32)); else host->bits_per_word_mask = (SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)); host->bits_per_word_mask &= SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word); if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts; if (mpc8xxx_spi->set_shifts) /* 8 bits per word and MSB first */ mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift, &mpc8xxx_spi->tx_shift, 8, 1); /* Register for SPI Interrupt */ ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq, 0, "fsl_spi", mpc8xxx_spi); if (ret != 0) goto err_probe; reg_base = mpc8xxx_spi->reg_base; /* SPI controller initializations */ mpc8xxx_spi_write_reg(®_base->mode, 0); mpc8xxx_spi_write_reg(®_base->mask, 0); mpc8xxx_spi_write_reg(®_base->command, 0); mpc8xxx_spi_write_reg(®_base->event, 0xffffffff); /* Enable SPI interface */ regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE; if (mpc8xxx_spi->max_bits_per_word < 8) { regval &= ~SPMODE_LEN(0xF); regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1); } if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) regval |= SPMODE_OP; mpc8xxx_spi_write_reg(®_base->mode, regval); ret = devm_spi_register_controller(dev, host); if (ret < 0) goto err_probe; dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base, mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags)); return host; err_probe: fsl_spi_cpm_free(mpc8xxx_spi); err_cpm_init: spi_controller_put(host); err: return ERR_PTR(ret); } static int of_fsl_spi_probe(struct platform_device *ofdev) { struct device *dev = &ofdev->dev; struct device_node *np = ofdev->dev.of_node; struct spi_controller *host; struct resource mem; int irq, type; int ret; bool spisel_boot = false; #if IS_ENABLED(CONFIG_FSL_SOC) struct mpc8xxx_spi_probe_info *pinfo = NULL; #endif ret = of_mpc8xxx_spi_probe(ofdev); if (ret) return ret; type = fsl_spi_get_type(&ofdev->dev); if (type == TYPE_FSL) { struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); #if IS_ENABLED(CONFIG_FSL_SOC) pinfo = to_of_pinfo(pdata); spisel_boot = of_property_read_bool(np, "fsl,spisel_boot"); if (spisel_boot) { pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4); if (!pinfo->immr_spi_cs) return -ENOMEM; } #endif /* * Handle the case where we have one hardwired (always selected) * device on the first "chipselect". Else we let the core code * handle any GPIOs or native chip selects and assign the * appropriate callback for dealing with the CS lines. This isn't * supported on the GRLIB variant. */ ret = gpiod_count(dev, "cs"); if (ret < 0) ret = 0; if (ret == 0 && !spisel_boot) pdata->max_chipselect = 1; else pdata->max_chipselect = ret + spisel_boot; } ret = of_address_to_resource(np, 0, &mem); if (ret) goto unmap_out; irq = platform_get_irq(ofdev, 0); if (irq < 0) { ret = irq; goto unmap_out; } host = fsl_spi_probe(dev, &mem, irq); return PTR_ERR_OR_ZERO(host); unmap_out: #if IS_ENABLED(CONFIG_FSL_SOC) if (spisel_boot) iounmap(pinfo->immr_spi_cs); #endif return ret; } static void of_fsl_spi_remove(struct platform_device *ofdev) { struct spi_controller *host = platform_get_drvdata(ofdev); struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host); fsl_spi_cpm_free(mpc8xxx_spi); } static struct platform_driver of_fsl_spi_driver = { .driver = { .name = "fsl_spi", .of_match_table = of_fsl_spi_match, }, .probe = of_fsl_spi_probe, .remove = of_fsl_spi_remove, }; #ifdef CONFIG_MPC832x_RDB /* * XXX XXX XXX * This is "legacy" platform driver, was used by the MPC8323E-RDB boards * only. The driver should go away soon, since newer MPC8323E-RDB's device * tree can work with OpenFirmware driver. But for now we support old trees * as well. */ static int plat_mpc8xxx_spi_probe(struct platform_device *pdev) { struct resource *mem; int irq; struct spi_controller *host; if (!dev_get_platdata(&pdev->dev)) return -EINVAL; mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!mem) return -EINVAL; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; host = fsl_spi_probe(&pdev->dev, mem, irq); return PTR_ERR_OR_ZERO(host); } static void plat_mpc8xxx_spi_remove(struct platform_device *pdev) { struct spi_controller *host = platform_get_drvdata(pdev); struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host); fsl_spi_cpm_free(mpc8xxx_spi); } MODULE_ALIAS("platform:mpc8xxx_spi"); static struct platform_driver mpc8xxx_spi_driver = { .probe = plat_mpc8xxx_spi_probe, .remove = plat_mpc8xxx_spi_remove, .driver = { .name = "mpc8xxx_spi", }, }; static bool legacy_driver_failed; static void __init legacy_driver_register(void) { legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver); } static void __exit legacy_driver_unregister(void) { if (legacy_driver_failed) return; platform_driver_unregister(&mpc8xxx_spi_driver); } #else static void __init legacy_driver_register(void) {} static void __exit legacy_driver_unregister(void) {} #endif /* CONFIG_MPC832x_RDB */ static int __init fsl_spi_init(void) { legacy_driver_register(); return platform_driver_register(&of_fsl_spi_driver); } module_init(fsl_spi_init); static void __exit fsl_spi_exit(void) { platform_driver_unregister(&of_fsl_spi_driver); legacy_driver_unregister(); } module_exit(fsl_spi_exit); MODULE_AUTHOR("Kumar Gala"); MODULE_DESCRIPTION("Simple Freescale SPI Driver"); MODULE_LICENSE("GPL");