diff options
Diffstat (limited to 'drivers/spi/spi-ingenic.c')
-rw-r--r-- | drivers/spi/spi-ingenic.c | 519 |
1 files changed, 519 insertions, 0 deletions
diff --git a/drivers/spi/spi-ingenic.c b/drivers/spi/spi-ingenic.c new file mode 100644 index 000000000..713a238be --- /dev/null +++ b/drivers/spi/spi-ingenic.c @@ -0,0 +1,519 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SPI bus driver for the Ingenic SoCs + * Copyright (c) 2017-2021 Artur Rojek <contact@artur-rojek.eu> + * Copyright (c) 2017-2021 Paul Cercueil <paul@crapouillou.net> + * Copyright (c) 2022 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> + +#define REG_SSIDR 0x0 +#define REG_SSICR0 0x4 +#define REG_SSICR1 0x8 +#define REG_SSISR 0xc +#define REG_SSIGR 0x18 + +#define REG_SSICR0_TENDIAN_LSB BIT(19) +#define REG_SSICR0_RENDIAN_LSB BIT(17) +#define REG_SSICR0_SSIE BIT(15) +#define REG_SSICR0_LOOP BIT(10) +#define REG_SSICR0_EACLRUN BIT(7) +#define REG_SSICR0_FSEL BIT(6) +#define REG_SSICR0_TFLUSH BIT(2) +#define REG_SSICR0_RFLUSH BIT(1) + +#define REG_SSICR1_FRMHL_MASK (BIT(31) | BIT(30)) +#define REG_SSICR1_FRMHL BIT(30) +#define REG_SSICR1_LFST BIT(25) +#define REG_SSICR1_UNFIN BIT(23) +#define REG_SSICR1_PHA BIT(1) +#define REG_SSICR1_POL BIT(0) + +#define REG_SSISR_END BIT(7) +#define REG_SSISR_BUSY BIT(6) +#define REG_SSISR_TFF BIT(5) +#define REG_SSISR_RFE BIT(4) +#define REG_SSISR_RFHF BIT(2) +#define REG_SSISR_UNDR BIT(1) +#define REG_SSISR_OVER BIT(0) + +#define SPI_INGENIC_FIFO_SIZE 128u + +struct jz_soc_info { + u32 bits_per_word_mask; + struct reg_field flen_field; + bool has_trendian; + + unsigned int max_speed_hz; + unsigned int max_native_cs; +}; + +struct ingenic_spi { + const struct jz_soc_info *soc_info; + struct clk *clk; + struct resource *mem_res; + + struct regmap *map; + struct regmap_field *flen_field; +}; + +static int spi_ingenic_wait(struct ingenic_spi *priv, + unsigned long mask, + bool condition) +{ + unsigned int val; + + return regmap_read_poll_timeout(priv->map, REG_SSISR, val, + !!(val & mask) == condition, + 100, 10000); +} + +static void spi_ingenic_set_cs(struct spi_device *spi, bool disable) +{ + struct ingenic_spi *priv = spi_controller_get_devdata(spi->controller); + + if (disable) { + regmap_clear_bits(priv->map, REG_SSICR1, REG_SSICR1_UNFIN); + regmap_clear_bits(priv->map, REG_SSISR, + REG_SSISR_UNDR | REG_SSISR_OVER); + + spi_ingenic_wait(priv, REG_SSISR_END, true); + } else { + regmap_set_bits(priv->map, REG_SSICR1, REG_SSICR1_UNFIN); + } + + regmap_set_bits(priv->map, REG_SSICR0, + REG_SSICR0_RFLUSH | REG_SSICR0_TFLUSH); +} + +static void spi_ingenic_prepare_transfer(struct ingenic_spi *priv, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + unsigned long clk_hz = clk_get_rate(priv->clk); + u32 cdiv, speed_hz = xfer->speed_hz ?: spi->max_speed_hz, + bits_per_word = xfer->bits_per_word ?: spi->bits_per_word; + + cdiv = clk_hz / (speed_hz * 2); + cdiv = clamp(cdiv, 1u, 0x100u) - 1; + + regmap_write(priv->map, REG_SSIGR, cdiv); + + regmap_field_write(priv->flen_field, bits_per_word - 2); +} + +static void spi_ingenic_finalize_transfer(void *controller) +{ + spi_finalize_current_transfer(controller); +} + +static struct dma_async_tx_descriptor * +spi_ingenic_prepare_dma(struct spi_controller *ctlr, struct dma_chan *chan, + struct sg_table *sg, enum dma_transfer_direction dir, + unsigned int bits) +{ + struct ingenic_spi *priv = spi_controller_get_devdata(ctlr); + struct dma_slave_config cfg = { + .direction = dir, + .src_addr = priv->mem_res->start + REG_SSIDR, + .dst_addr = priv->mem_res->start + REG_SSIDR, + }; + struct dma_async_tx_descriptor *desc; + dma_cookie_t cookie; + int ret; + + if (bits > 16) { + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + cfg.src_maxburst = cfg.dst_maxburst = 4; + } else if (bits > 8) { + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; + cfg.src_maxburst = cfg.dst_maxburst = 2; + } else { + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + cfg.src_maxburst = cfg.dst_maxburst = 1; + } + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) + return ERR_PTR(ret); + + desc = dmaengine_prep_slave_sg(chan, sg->sgl, sg->nents, dir, + DMA_PREP_INTERRUPT); + if (!desc) + return ERR_PTR(-ENOMEM); + + if (dir == DMA_DEV_TO_MEM) { + desc->callback = spi_ingenic_finalize_transfer; + desc->callback_param = ctlr; + } + + cookie = dmaengine_submit(desc); + + ret = dma_submit_error(cookie); + if (ret) { + dmaengine_desc_free(desc); + return ERR_PTR(ret); + } + + return desc; +} + +static int spi_ingenic_dma_tx(struct spi_controller *ctlr, + struct spi_transfer *xfer, unsigned int bits) +{ + struct dma_async_tx_descriptor *rx_desc, *tx_desc; + + rx_desc = spi_ingenic_prepare_dma(ctlr, ctlr->dma_rx, + &xfer->rx_sg, DMA_DEV_TO_MEM, bits); + if (IS_ERR(rx_desc)) + return PTR_ERR(rx_desc); + + tx_desc = spi_ingenic_prepare_dma(ctlr, ctlr->dma_tx, + &xfer->tx_sg, DMA_MEM_TO_DEV, bits); + if (IS_ERR(tx_desc)) { + dmaengine_terminate_async(ctlr->dma_rx); + dmaengine_desc_free(rx_desc); + return PTR_ERR(tx_desc); + } + + dma_async_issue_pending(ctlr->dma_rx); + dma_async_issue_pending(ctlr->dma_tx); + + return 1; +} + +#define SPI_INGENIC_TX(x) \ +static int spi_ingenic_tx##x(struct ingenic_spi *priv, \ + struct spi_transfer *xfer) \ +{ \ + unsigned int count = xfer->len / (x / 8); \ + unsigned int prefill = min(count, SPI_INGENIC_FIFO_SIZE); \ + const u##x *tx_buf = xfer->tx_buf; \ + u##x *rx_buf = xfer->rx_buf; \ + unsigned int i, val; \ + int err; \ + \ + /* Fill up the TX fifo */ \ + for (i = 0; i < prefill; i++) { \ + val = tx_buf ? tx_buf[i] : 0; \ + \ + regmap_write(priv->map, REG_SSIDR, val); \ + } \ + \ + for (i = 0; i < count; i++) { \ + err = spi_ingenic_wait(priv, REG_SSISR_RFE, false); \ + if (err) \ + return err; \ + \ + regmap_read(priv->map, REG_SSIDR, &val); \ + if (rx_buf) \ + rx_buf[i] = val; \ + \ + if (i < count - prefill) { \ + val = tx_buf ? tx_buf[i + prefill] : 0; \ + \ + regmap_write(priv->map, REG_SSIDR, val); \ + } \ + } \ + \ + return 0; \ +} +SPI_INGENIC_TX(8) +SPI_INGENIC_TX(16) +SPI_INGENIC_TX(32) +#undef SPI_INGENIC_TX + +static int spi_ingenic_transfer_one(struct spi_controller *ctlr, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct ingenic_spi *priv = spi_controller_get_devdata(ctlr); + unsigned int bits = xfer->bits_per_word ?: spi->bits_per_word; + bool can_dma = ctlr->can_dma && ctlr->can_dma(ctlr, spi, xfer); + + spi_ingenic_prepare_transfer(priv, spi, xfer); + + if (ctlr->cur_msg_mapped && can_dma) + return spi_ingenic_dma_tx(ctlr, xfer, bits); + + if (bits > 16) + return spi_ingenic_tx32(priv, xfer); + + if (bits > 8) + return spi_ingenic_tx16(priv, xfer); + + return spi_ingenic_tx8(priv, xfer); +} + +static int spi_ingenic_prepare_message(struct spi_controller *ctlr, + struct spi_message *message) +{ + struct ingenic_spi *priv = spi_controller_get_devdata(ctlr); + struct spi_device *spi = message->spi; + unsigned int cs = REG_SSICR1_FRMHL << spi->chip_select; + unsigned int ssicr0_mask = REG_SSICR0_LOOP | REG_SSICR0_FSEL; + unsigned int ssicr1_mask = REG_SSICR1_PHA | REG_SSICR1_POL | cs; + unsigned int ssicr0 = 0, ssicr1 = 0; + + if (priv->soc_info->has_trendian) { + ssicr0_mask |= REG_SSICR0_RENDIAN_LSB | REG_SSICR0_TENDIAN_LSB; + + if (spi->mode & SPI_LSB_FIRST) + ssicr0 |= REG_SSICR0_RENDIAN_LSB | REG_SSICR0_TENDIAN_LSB; + } else { + ssicr1_mask |= REG_SSICR1_LFST; + + if (spi->mode & SPI_LSB_FIRST) + ssicr1 |= REG_SSICR1_LFST; + } + + if (spi->mode & SPI_LOOP) + ssicr0 |= REG_SSICR0_LOOP; + if (spi->chip_select) + ssicr0 |= REG_SSICR0_FSEL; + + if (spi->mode & SPI_CPHA) + ssicr1 |= REG_SSICR1_PHA; + if (spi->mode & SPI_CPOL) + ssicr1 |= REG_SSICR1_POL; + if (spi->mode & SPI_CS_HIGH) + ssicr1 |= cs; + + regmap_update_bits(priv->map, REG_SSICR0, ssicr0_mask, ssicr0); + regmap_update_bits(priv->map, REG_SSICR1, ssicr1_mask, ssicr1); + + return 0; +} + +static int spi_ingenic_prepare_hardware(struct spi_controller *ctlr) +{ + struct ingenic_spi *priv = spi_controller_get_devdata(ctlr); + int ret; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + regmap_write(priv->map, REG_SSICR0, REG_SSICR0_EACLRUN); + regmap_write(priv->map, REG_SSICR1, 0); + regmap_write(priv->map, REG_SSISR, 0); + regmap_set_bits(priv->map, REG_SSICR0, REG_SSICR0_SSIE); + + return 0; +} + +static int spi_ingenic_unprepare_hardware(struct spi_controller *ctlr) +{ + struct ingenic_spi *priv = spi_controller_get_devdata(ctlr); + + regmap_clear_bits(priv->map, REG_SSICR0, REG_SSICR0_SSIE); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static bool spi_ingenic_can_dma(struct spi_controller *ctlr, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct dma_slave_caps caps; + int ret; + + ret = dma_get_slave_caps(ctlr->dma_tx, &caps); + if (ret) { + dev_err(&spi->dev, "Unable to get slave caps: %d\n", ret); + return false; + } + + return !caps.max_sg_burst || + xfer->len <= caps.max_sg_burst * SPI_INGENIC_FIFO_SIZE; +} + +static int spi_ingenic_request_dma(struct spi_controller *ctlr, + struct device *dev) +{ + ctlr->dma_tx = dma_request_slave_channel(dev, "tx"); + if (!ctlr->dma_tx) + return -ENODEV; + + ctlr->dma_rx = dma_request_slave_channel(dev, "rx"); + + if (!ctlr->dma_rx) + return -ENODEV; + + ctlr->can_dma = spi_ingenic_can_dma; + + return 0; +} + +static void spi_ingenic_release_dma(void *data) +{ + struct spi_controller *ctlr = data; + + if (ctlr->dma_tx) + dma_release_channel(ctlr->dma_tx); + if (ctlr->dma_rx) + dma_release_channel(ctlr->dma_rx); +} + +static const struct regmap_config spi_ingenic_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .max_register = REG_SSIGR, +}; + +static int spi_ingenic_probe(struct platform_device *pdev) +{ + const struct jz_soc_info *pdata; + struct device *dev = &pdev->dev; + struct spi_controller *ctlr; + struct ingenic_spi *priv; + void __iomem *base; + int num_cs, ret; + + pdata = of_device_get_match_data(dev); + if (!pdata) { + dev_err(dev, "Missing platform data.\n"); + return -EINVAL; + } + + ctlr = devm_spi_alloc_master(dev, sizeof(*priv)); + if (!ctlr) { + dev_err(dev, "Unable to allocate SPI controller.\n"); + return -ENOMEM; + } + + priv = spi_controller_get_devdata(ctlr); + priv->soc_info = pdata; + + priv->clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->clk)) { + return dev_err_probe(dev, PTR_ERR(priv->clk), + "Unable to get clock.\n"); + } + + base = devm_platform_get_and_ioremap_resource(pdev, 0, &priv->mem_res); + if (IS_ERR(base)) + return PTR_ERR(base); + + priv->map = devm_regmap_init_mmio(dev, base, &spi_ingenic_regmap_config); + if (IS_ERR(priv->map)) + return PTR_ERR(priv->map); + + priv->flen_field = devm_regmap_field_alloc(dev, priv->map, + pdata->flen_field); + if (IS_ERR(priv->flen_field)) + return PTR_ERR(priv->flen_field); + + if (device_property_read_u32(dev, "num-cs", &num_cs)) + num_cs = pdata->max_native_cs; + + platform_set_drvdata(pdev, ctlr); + + ctlr->prepare_transfer_hardware = spi_ingenic_prepare_hardware; + ctlr->unprepare_transfer_hardware = spi_ingenic_unprepare_hardware; + ctlr->prepare_message = spi_ingenic_prepare_message; + ctlr->set_cs = spi_ingenic_set_cs; + ctlr->transfer_one = spi_ingenic_transfer_one; + ctlr->mode_bits = SPI_MODE_3 | SPI_LSB_FIRST | SPI_LOOP | SPI_CS_HIGH; + ctlr->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX; + ctlr->max_dma_len = SPI_INGENIC_FIFO_SIZE; + ctlr->bits_per_word_mask = pdata->bits_per_word_mask; + ctlr->min_speed_hz = 7200; + ctlr->max_speed_hz = pdata->max_speed_hz; + ctlr->use_gpio_descriptors = true; + ctlr->max_native_cs = pdata->max_native_cs; + ctlr->num_chipselect = num_cs; + ctlr->dev.of_node = pdev->dev.of_node; + + if (spi_ingenic_request_dma(ctlr, dev)) + dev_warn(dev, "DMA not available.\n"); + + ret = devm_add_action_or_reset(dev, spi_ingenic_release_dma, ctlr); + if (ret) { + dev_err(dev, "Unable to add action.\n"); + return ret; + } + + ret = devm_spi_register_controller(dev, ctlr); + if (ret) + dev_err(dev, "Unable to register SPI controller.\n"); + + return ret; +} + +static const struct jz_soc_info jz4750_soc_info = { + .bits_per_word_mask = SPI_BPW_RANGE_MASK(2, 17), + .flen_field = REG_FIELD(REG_SSICR1, 4, 7), + .has_trendian = false, + + .max_speed_hz = 54000000, + .max_native_cs = 2, +}; + +static const struct jz_soc_info jz4780_soc_info = { + .bits_per_word_mask = SPI_BPW_RANGE_MASK(2, 32), + .flen_field = REG_FIELD(REG_SSICR1, 3, 7), + .has_trendian = true, + + .max_speed_hz = 54000000, + .max_native_cs = 2, +}; + +static const struct jz_soc_info x1000_soc_info = { + .bits_per_word_mask = SPI_BPW_RANGE_MASK(2, 32), + .flen_field = REG_FIELD(REG_SSICR1, 3, 7), + .has_trendian = true, + + .max_speed_hz = 50000000, + .max_native_cs = 2, +}; + +static const struct jz_soc_info x2000_soc_info = { + .bits_per_word_mask = SPI_BPW_RANGE_MASK(2, 32), + .flen_field = REG_FIELD(REG_SSICR1, 3, 7), + .has_trendian = true, + + .max_speed_hz = 50000000, + .max_native_cs = 1, +}; + +static const struct of_device_id spi_ingenic_of_match[] = { + { .compatible = "ingenic,jz4750-spi", .data = &jz4750_soc_info }, + { .compatible = "ingenic,jz4775-spi", .data = &jz4780_soc_info }, + { .compatible = "ingenic,jz4780-spi", .data = &jz4780_soc_info }, + { .compatible = "ingenic,x1000-spi", .data = &x1000_soc_info }, + { .compatible = "ingenic,x2000-spi", .data = &x2000_soc_info }, + {} +}; +MODULE_DEVICE_TABLE(of, spi_ingenic_of_match); + +static struct platform_driver spi_ingenic_driver = { + .driver = { + .name = "spi-ingenic", + .of_match_table = spi_ingenic_of_match, + }, + .probe = spi_ingenic_probe, +}; + +module_platform_driver(spi_ingenic_driver); +MODULE_DESCRIPTION("SPI bus driver for the Ingenic SoCs"); +MODULE_AUTHOR("Artur Rojek <contact@artur-rojek.eu>"); +MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>"); +MODULE_AUTHOR("周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>"); +MODULE_LICENSE("GPL"); |