// SPDX-License-Identifier: GPL-2.0-only /* * Memory-mapped interface driver for DW SPI Core * * Copyright (c) 2010, Octasic semiconductor. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "spi-dw.h" #define DRIVER_NAME "dw_spi_mmio" struct dw_spi_mmio { struct dw_spi dws; struct clk *clk; struct clk *pclk; void *priv; struct reset_control *rstc; }; #define MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL 0x24 #define OCELOT_IF_SI_OWNER_OFFSET 4 #define JAGUAR2_IF_SI_OWNER_OFFSET 6 #define MSCC_IF_SI_OWNER_MASK GENMASK(1, 0) #define MSCC_IF_SI_OWNER_SISL 0 #define MSCC_IF_SI_OWNER_SIBM 1 #define MSCC_IF_SI_OWNER_SIMC 2 #define MSCC_SPI_MST_SW_MODE 0x14 #define MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE BIT(13) #define MSCC_SPI_MST_SW_MODE_SW_SPI_CS(x) (x << 5) #define SPARX5_FORCE_ENA 0xa4 #define SPARX5_FORCE_VAL 0xa8 struct dw_spi_mscc { struct regmap *syscon; void __iomem *spi_mst; /* Not sparx5 */ }; /* * Elba SoC does not use ssi, pin override is used for cs 0,1 and * gpios for cs 2,3 as defined in the device tree. * * cs: | 1 0 * bit: |---3-------2-------1-------0 * | cs1 cs1_ovr cs0 cs0_ovr */ #define ELBA_SPICS_REG 0x2468 #define ELBA_SPICS_OFFSET(cs) ((cs) << 1) #define ELBA_SPICS_MASK(cs) (GENMASK(1, 0) << ELBA_SPICS_OFFSET(cs)) #define ELBA_SPICS_SET(cs, val) \ ((((val) << 1) | BIT(0)) << ELBA_SPICS_OFFSET(cs)) /* * The Designware SPI controller (referred to as master in the documentation) * automatically deasserts chip select when the tx fifo is empty. The chip * selects then needs to be either driven as GPIOs or, for the first 4 using * the SPI boot controller registers. the final chip select is an OR gate * between the Designware SPI controller and the SPI boot controller. */ static void dw_spi_mscc_set_cs(struct spi_device *spi, bool enable) { struct dw_spi *dws = spi_controller_get_devdata(spi->controller); struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws); struct dw_spi_mscc *dwsmscc = dwsmmio->priv; u32 cs = spi_get_chipselect(spi, 0); if (cs < 4) { u32 sw_mode = MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE; if (!enable) sw_mode |= MSCC_SPI_MST_SW_MODE_SW_SPI_CS(BIT(cs)); writel(sw_mode, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE); } dw_spi_set_cs(spi, enable); } static int dw_spi_mscc_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio, const char *cpu_syscon, u32 if_si_owner_offset) { struct dw_spi_mscc *dwsmscc; dwsmscc = devm_kzalloc(&pdev->dev, sizeof(*dwsmscc), GFP_KERNEL); if (!dwsmscc) return -ENOMEM; dwsmscc->spi_mst = devm_platform_ioremap_resource(pdev, 1); if (IS_ERR(dwsmscc->spi_mst)) { dev_err(&pdev->dev, "SPI_MST region map failed\n"); return PTR_ERR(dwsmscc->spi_mst); } dwsmscc->syscon = syscon_regmap_lookup_by_compatible(cpu_syscon); if (IS_ERR(dwsmscc->syscon)) return PTR_ERR(dwsmscc->syscon); /* Deassert all CS */ writel(0, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE); /* Select the owner of the SI interface */ regmap_update_bits(dwsmscc->syscon, MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL, MSCC_IF_SI_OWNER_MASK << if_si_owner_offset, MSCC_IF_SI_OWNER_SIMC << if_si_owner_offset); dwsmmio->dws.set_cs = dw_spi_mscc_set_cs; dwsmmio->priv = dwsmscc; return 0; } static int dw_spi_mscc_ocelot_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { return dw_spi_mscc_init(pdev, dwsmmio, "mscc,ocelot-cpu-syscon", OCELOT_IF_SI_OWNER_OFFSET); } static int dw_spi_mscc_jaguar2_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { return dw_spi_mscc_init(pdev, dwsmmio, "mscc,jaguar2-cpu-syscon", JAGUAR2_IF_SI_OWNER_OFFSET); } /* * The Designware SPI controller (referred to as master in the * documentation) automatically deasserts chip select when the tx fifo * is empty. The chip selects then needs to be driven by a CS override * register. enable is an active low signal. */ static void dw_spi_sparx5_set_cs(struct spi_device *spi, bool enable) { struct dw_spi *dws = spi_controller_get_devdata(spi->controller); struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws); struct dw_spi_mscc *dwsmscc = dwsmmio->priv; u8 cs = spi_get_chipselect(spi, 0); if (!enable) { /* CS override drive enable */ regmap_write(dwsmscc->syscon, SPARX5_FORCE_ENA, 1); /* Now set CSx enabled */ regmap_write(dwsmscc->syscon, SPARX5_FORCE_VAL, ~BIT(cs)); /* Allow settle */ usleep_range(1, 5); } else { /* CS value */ regmap_write(dwsmscc->syscon, SPARX5_FORCE_VAL, ~0); /* Allow settle */ usleep_range(1, 5); /* CS override drive disable */ regmap_write(dwsmscc->syscon, SPARX5_FORCE_ENA, 0); } dw_spi_set_cs(spi, enable); } static int dw_spi_mscc_sparx5_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { const char *syscon_name = "microchip,sparx5-cpu-syscon"; struct device *dev = &pdev->dev; struct dw_spi_mscc *dwsmscc; if (!IS_ENABLED(CONFIG_SPI_MUX)) { dev_err(dev, "This driver needs CONFIG_SPI_MUX\n"); return -EOPNOTSUPP; } dwsmscc = devm_kzalloc(dev, sizeof(*dwsmscc), GFP_KERNEL); if (!dwsmscc) return -ENOMEM; dwsmscc->syscon = syscon_regmap_lookup_by_compatible(syscon_name); if (IS_ERR(dwsmscc->syscon)) { dev_err(dev, "No syscon map %s\n", syscon_name); return PTR_ERR(dwsmscc->syscon); } dwsmmio->dws.set_cs = dw_spi_sparx5_set_cs; dwsmmio->priv = dwsmscc; return 0; } static int dw_spi_alpine_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { dwsmmio->dws.caps = DW_SPI_CAP_CS_OVERRIDE; return 0; } static int dw_spi_pssi_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { dw_spi_dma_setup_generic(&dwsmmio->dws); return 0; } static int dw_spi_hssi_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { dwsmmio->dws.ip = DW_HSSI_ID; dw_spi_dma_setup_generic(&dwsmmio->dws); return 0; } static int dw_spi_intel_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { dwsmmio->dws.ip = DW_HSSI_ID; return 0; } /* * DMA-based mem ops are not configured for this device and are not tested. */ static int dw_spi_mountevans_imc_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { /* * The Intel Mount Evans SoC's Integrated Management Complex DW * apb_ssi_v4.02a controller has an errata where a full TX FIFO can * result in data corruption. The suggested workaround is to never * completely fill the FIFO. The TX FIFO has a size of 32 so the * fifo_len is set to 31. */ dwsmmio->dws.fifo_len = 31; return 0; } static int dw_spi_canaan_k210_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { /* * The Canaan Kendryte K210 SoC DW apb_ssi v4 spi controller is * documented to have a 32 word deep TX and RX FIFO, which * spi_hw_init() detects. However, when the RX FIFO is filled up to * 32 entries (RXFLR = 32), an RX FIFO overrun error occurs. Avoid this * problem by force setting fifo_len to 31. */ dwsmmio->dws.fifo_len = 31; return 0; } static void dw_spi_elba_override_cs(struct regmap *syscon, int cs, int enable) { regmap_update_bits(syscon, ELBA_SPICS_REG, ELBA_SPICS_MASK(cs), ELBA_SPICS_SET(cs, enable)); } static void dw_spi_elba_set_cs(struct spi_device *spi, bool enable) { struct dw_spi *dws = spi_controller_get_devdata(spi->controller); struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws); struct regmap *syscon = dwsmmio->priv; u8 cs; cs = spi_get_chipselect(spi, 0); if (cs < 2) dw_spi_elba_override_cs(syscon, spi_get_chipselect(spi, 0), enable); /* * The DW SPI controller needs a native CS bit selected to start * the serial engine. */ spi_set_chipselect(spi, 0, 0); dw_spi_set_cs(spi, enable); spi_set_chipselect(spi, 0, cs); } static int dw_spi_elba_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { struct regmap *syscon; syscon = syscon_regmap_lookup_by_phandle(dev_of_node(&pdev->dev), "amd,pensando-elba-syscon"); if (IS_ERR(syscon)) return dev_err_probe(&pdev->dev, PTR_ERR(syscon), "syscon regmap lookup failed\n"); dwsmmio->priv = syscon; dwsmmio->dws.set_cs = dw_spi_elba_set_cs; return 0; } static int dw_spi_mmio_probe(struct platform_device *pdev) { int (*init_func)(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio); struct dw_spi_mmio *dwsmmio; struct resource *mem; struct dw_spi *dws; int ret; int num_cs; dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio), GFP_KERNEL); if (!dwsmmio) return -ENOMEM; dws = &dwsmmio->dws; /* Get basic io resource and map it */ dws->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem); if (IS_ERR(dws->regs)) return PTR_ERR(dws->regs); dws->paddr = mem->start; dws->irq = platform_get_irq(pdev, 0); if (dws->irq < 0) return dws->irq; /* -ENXIO */ dwsmmio->clk = devm_clk_get_enabled(&pdev->dev, NULL); if (IS_ERR(dwsmmio->clk)) return PTR_ERR(dwsmmio->clk); /* Optional clock needed to access the registers */ dwsmmio->pclk = devm_clk_get_optional_enabled(&pdev->dev, "pclk"); if (IS_ERR(dwsmmio->pclk)) return PTR_ERR(dwsmmio->pclk); /* find an optional reset controller */ dwsmmio->rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, "spi"); if (IS_ERR(dwsmmio->rstc)) return PTR_ERR(dwsmmio->rstc); reset_control_deassert(dwsmmio->rstc); dws->bus_num = pdev->id; dws->max_freq = clk_get_rate(dwsmmio->clk); if (device_property_read_u32(&pdev->dev, "reg-io-width", &dws->reg_io_width)) dws->reg_io_width = 4; num_cs = 4; device_property_read_u32(&pdev->dev, "num-cs", &num_cs); dws->num_cs = num_cs; init_func = device_get_match_data(&pdev->dev); if (init_func) { ret = init_func(pdev, dwsmmio); if (ret) goto out_reset; } pm_runtime_enable(&pdev->dev); ret = dw_spi_add_host(&pdev->dev, dws); if (ret) goto out; platform_set_drvdata(pdev, dwsmmio); return 0; out: pm_runtime_disable(&pdev->dev); out_reset: reset_control_assert(dwsmmio->rstc); return ret; } static void dw_spi_mmio_remove(struct platform_device *pdev) { struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev); dw_spi_remove_host(&dwsmmio->dws); pm_runtime_disable(&pdev->dev); reset_control_assert(dwsmmio->rstc); } static const struct of_device_id dw_spi_mmio_of_match[] = { { .compatible = "snps,dw-apb-ssi", .data = dw_spi_pssi_init}, { .compatible = "mscc,ocelot-spi", .data = dw_spi_mscc_ocelot_init}, { .compatible = "mscc,jaguar2-spi", .data = dw_spi_mscc_jaguar2_init}, { .compatible = "amazon,alpine-dw-apb-ssi", .data = dw_spi_alpine_init}, { .compatible = "renesas,rzn1-spi", .data = dw_spi_pssi_init}, { .compatible = "snps,dwc-ssi-1.01a", .data = dw_spi_hssi_init}, { .compatible = "intel,keembay-ssi", .data = dw_spi_intel_init}, { .compatible = "intel,mountevans-imc-ssi", .data = dw_spi_mountevans_imc_init, }, { .compatible = "microchip,sparx5-spi", dw_spi_mscc_sparx5_init}, { .compatible = "canaan,k210-spi", dw_spi_canaan_k210_init}, { .compatible = "amd,pensando-elba-spi", .data = dw_spi_elba_init}, { /* end of table */} }; MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match); #ifdef CONFIG_ACPI static const struct acpi_device_id dw_spi_mmio_acpi_match[] = { {"HISI0173", (kernel_ulong_t)dw_spi_pssi_init}, {}, }; MODULE_DEVICE_TABLE(acpi, dw_spi_mmio_acpi_match); #endif static struct platform_driver dw_spi_mmio_driver = { .probe = dw_spi_mmio_probe, .remove_new = dw_spi_mmio_remove, .driver = { .name = DRIVER_NAME, .of_match_table = dw_spi_mmio_of_match, .acpi_match_table = ACPI_PTR(dw_spi_mmio_acpi_match), }, }; module_platform_driver(dw_spi_mmio_driver); MODULE_AUTHOR("Jean-Hugues Deschenes "); MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core"); MODULE_LICENSE("GPL v2"); MODULE_IMPORT_NS(SPI_DW_CORE);