This adds support for the SPI controller found on many Rockchip SoCs. The driver is based on the corresponding Linux driver as of Linux-6.12-rc1. Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> --- drivers/spi/Makefile | 1 + drivers/spi/spi-rockchip.c | 584 +++++++++++++++++++++++++++++++++++++++++++++ include/spi/spi.h | 7 + 3 files changed, 592 insertions(+) diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 68a8c4e675..f9aefdfe45 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -17,3 +17,4 @@ obj-$(CONFIG_SPI_ZYNQ_QSPI) += zynq_qspi.o obj-$(CONFIG_SPI_NXP_FLEXSPI) += spi-nxp-fspi.o obj-$(CONFIG_DRIVER_SPI_STM32) += stm32_spi.o obj-$(CONFIG_SPI_SIFIVE) += spi-sifive.o +obj-y += spi-rockchip.o diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c new file mode 100644 index 0000000000..1e81e9393f --- /dev/null +++ b/drivers/spi/spi-rockchip.c @@ -0,0 +1,584 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd + * Author: Addy Ke <addy.ke@xxxxxxxxxxxxxx> + */ + +#include <common.h> +#include <linux/clk.h> +#include <driver.h> +#include <errno.h> +#include <spi/spi.h> +#include <linux/spi/spi-mem.h> +#include <linux/bitops.h> +#include <clock.h> +#include <gpio.h> +#include <of_gpio.h> +#include <linux/bitfield.h> +#include <linux/iopoll.h> + +#define DRIVER_NAME "rockchip-spi" + +#define ROCKCHIP_SPI_CLR_BITS(reg, bits) \ + writel_relaxed(readl_relaxed(reg) & ~(bits), reg) +#define ROCKCHIP_SPI_SET_BITS(reg, bits) \ + writel_relaxed(readl_relaxed(reg) | (bits), reg) + +/* SPI register offsets */ +#define ROCKCHIP_SPI_CTRLR0 0x0000 +#define ROCKCHIP_SPI_CTRLR1 0x0004 +#define ROCKCHIP_SPI_SSIENR 0x0008 +#define ROCKCHIP_SPI_SER 0x000c +#define ROCKCHIP_SPI_BAUDR 0x0010 +#define ROCKCHIP_SPI_TXFTLR 0x0014 +#define ROCKCHIP_SPI_RXFTLR 0x0018 +#define ROCKCHIP_SPI_TXFLR 0x001c +#define ROCKCHIP_SPI_RXFLR 0x0020 +#define ROCKCHIP_SPI_SR 0x0024 +#define ROCKCHIP_SPI_IPR 0x0028 +#define ROCKCHIP_SPI_IMR 0x002c +#define ROCKCHIP_SPI_ISR 0x0030 +#define ROCKCHIP_SPI_RISR 0x0034 +#define ROCKCHIP_SPI_ICR 0x0038 +#define ROCKCHIP_SPI_DMACR 0x003c +#define ROCKCHIP_SPI_DMATDLR 0x0040 +#define ROCKCHIP_SPI_DMARDLR 0x0044 +#define ROCKCHIP_SPI_VERSION 0x0048 +#define ROCKCHIP_SPI_TXDR 0x0400 +#define ROCKCHIP_SPI_RXDR 0x0800 + +/* Bit fields in CTRLR0 */ +#define CR0_DFS_OFFSET 0 +#define CR0_DFS_4BIT 0x0 +#define CR0_DFS_8BIT 0x1 +#define CR0_DFS_16BIT 0x2 + +#define CR0_CFS_OFFSET 2 + +#define CR0_SCPH_OFFSET 6 + +#define CR0_SCPOL_OFFSET 7 + +#define CR0_CSM_OFFSET 8 +#define CR0_CSM_KEEP 0x0 +/* ss_n be high for half sclk_out cycles */ +#define CR0_CSM_HALF 0X1 +/* ss_n be high for one sclk_out cycle */ +#define CR0_CSM_ONE 0x2 + +/* ss_n to sclk_out delay */ +#define CR0_SSD_OFFSET 10 +/* + * The period between ss_n active and + * sclk_out active is half sclk_out cycles + */ +#define CR0_SSD_HALF 0x0 +/* + * The period between ss_n active and + * sclk_out active is one sclk_out cycle + */ +#define CR0_SSD_ONE 0x1 + +#define CR0_EM_OFFSET 11 +#define CR0_EM_LITTLE 0x0 +#define CR0_EM_BIG 0x1 + +#define CR0_FBM_OFFSET 12 +#define CR0_FBM_MSB 0x0 +#define CR0_FBM_LSB 0x1 + +#define CR0_BHT_OFFSET 13 +#define CR0_BHT_16BIT 0x0 +#define CR0_BHT_8BIT 0x1 + +#define CR0_RSD_OFFSET 14 +#define CR0_RSD_MAX 0x3 + +#define CR0_FRF_OFFSET 16 +#define CR0_FRF_SPI 0x0 +#define CR0_FRF_SSP 0x1 +#define CR0_FRF_MICROWIRE 0x2 + +#define CR0_XFM_OFFSET 18 +#define CR0_XFM_MASK (0x03 << SPI_XFM_OFFSET) +#define CR0_XFM_TR 0x0 +#define CR0_XFM_TO 0x1 +#define CR0_XFM_RO 0x2 + +#define CR0_OPM_OFFSET 20 +#define CR0_OPM_HOST 0x0 +#define CR0_OPM_TARGET 0x1 + +#define CR0_SOI_OFFSET 23 + +#define CR0_MTM_OFFSET 0x21 + +/* Bit fields in SER, 2bit */ +#define SER_MASK 0x3 + +/* Bit fields in BAUDR */ +#define BAUDR_SCKDV_MIN 2 +#define BAUDR_SCKDV_MAX 65534 + +/* Bit fields in SR, 6bit */ +#define SR_MASK 0x3f +#define SR_BUSY (1 << 0) +#define SR_TF_FULL (1 << 1) +#define SR_TF_EMPTY (1 << 2) +#define SR_RF_EMPTY (1 << 3) +#define SR_RF_FULL (1 << 4) +#define SR_TARGET_TX_BUSY (1 << 5) + +/* Bit fields in ISR, IMR, ISR, RISR, 5bit */ +#define INT_MASK 0x1f +#define INT_TF_EMPTY (1 << 0) +#define INT_TF_OVERFLOW (1 << 1) +#define INT_RF_UNDERFLOW (1 << 2) +#define INT_RF_OVERFLOW (1 << 3) +#define INT_RF_FULL (1 << 4) +#define INT_CS_INACTIVE (1 << 6) + +/* Bit fields in ICR, 4bit */ +#define ICR_MASK 0x0f +#define ICR_ALL (1 << 0) +#define ICR_RF_UNDERFLOW (1 << 1) +#define ICR_RF_OVERFLOW (1 << 2) +#define ICR_TF_OVERFLOW (1 << 3) + +/* Bit fields in DMACR */ +#define RF_DMA_EN (1 << 0) +#define TF_DMA_EN (1 << 1) + +/* Driver state flags */ +#define RXDMA (1 << 0) +#define TXDMA (1 << 1) + +/* sclk_out: spi host internal logic in rk3x can support 50Mhz */ +#define MAX_SCLK_OUT 50000000U + +/* + * SPI_CTRLR1 is 16-bits, so we should support lengths of 0xffff + 1. However, + * the controller seems to hang when given 0x10000, so stick with this for now. + */ +#define ROCKCHIP_SPI_MAX_TRANLEN 0xffff + +#define ROCKCHIP_SPI_MAX_NATIVE_CS_NUM 2 +#define ROCKCHIP_SPI_VER2_TYPE1 0x05EC0002 +#define ROCKCHIP_SPI_VER2_TYPE2 0x00110002 + +#define ROCKCHIP_AUTOSUSPEND_TIMEOUT 2000 + +struct rockchip_spi { + struct spi_controller ctlr; + struct device *dev; + + struct clk *spiclk; + struct clk *apb_pclk; + + void __iomem *regs; + + /*depth of the FIFO buffer */ + u32 fifo_len; + /* frequency of spiclk */ + u32 freq; + + u8 rsd; + + bool cs_high_supported; /* native CS supports active-high polarity */ + + struct spi_transfer *xfer; /* Store xfer temporarily */ +}; + +static inline void spi_enable_chip(struct rockchip_spi *rs, bool enable) +{ + writel_relaxed((enable ? 1U : 0U), rs->regs + ROCKCHIP_SPI_SSIENR); +} + +static inline void wait_for_tx_idle(struct rockchip_spi *rs, bool target_mode) +{ + u64 start = get_time_ns(); + + do { + if (target_mode) { + if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_TARGET_TX_BUSY) && + !((readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY))) + return; + } else { + if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY)) + return; + } + } while (!is_timeout(start, 5 * MSECOND)); + + dev_warn(rs->dev, "spi controller is in busy state!\n"); +} + +static u32 get_fifo_len(struct rockchip_spi *rs) +{ + u32 ver; + + ver = readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION); + + switch (ver) { + case ROCKCHIP_SPI_VER2_TYPE1: + case ROCKCHIP_SPI_VER2_TYPE2: + return 64; + default: + return 32; + } +} + +static inline struct gpio_desc *spi_get_csgpiod(const struct spi_device *spi, u8 idx) +{ + return NULL; +} + +static void rockchip_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct spi_controller *ctlr = spi->controller; + struct rockchip_spi *rs = spi_controller_get_devdata(ctlr); + bool cs_asserted = spi->mode & SPI_CS_HIGH ? !enable : enable; + + if (cs_asserted) { + if (spi_get_csgpiod(spi, 0)) + ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER, 1); + else + ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER, + BIT(spi_get_chipselect(spi, 0))); + } else { + if (spi_get_csgpiod(spi, 0)) + ROCKCHIP_SPI_CLR_BITS(rs->regs + ROCKCHIP_SPI_SER, 1); + else + ROCKCHIP_SPI_CLR_BITS(rs->regs + ROCKCHIP_SPI_SER, + BIT(spi_get_chipselect(spi, 0))); + } +} + +static int rockchip_spi_pio(struct rockchip_spi *rs, struct spi_transfer *xfer) +{ + int bytes_per_word = xfer->bits_per_word <= 8 ? 1 : 2; + const void *txbuf = xfer->tx_buf; + void *rxbuf = xfer->rx_buf; + int rxwords, txwords; + + txwords = rxwords = xfer->len / bytes_per_word; + + while (1) { + unsigned int fifowords = readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR); + unsigned int tx_free = rs->fifo_len - fifowords; + + if (tx_free && txwords) { + u32 txw; + + if (!txbuf) + txw = 0; + else if (bytes_per_word == 1) + txw = *(u8 *)txbuf; + else + txw = *(u16 *)txbuf; + + writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR); + + if (txbuf) + txbuf += bytes_per_word; + + txwords--; + } + + fifowords = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR); + + if (fifowords) { + u32 rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR); + + if (rxbuf) { + if (bytes_per_word == 1) + *(u8 *)rxbuf = (u8)rxw; + else + *(u16 *)rxbuf = (u16)rxw; + rxbuf += bytes_per_word; + } + + rxwords--; + } + + if (!rxwords) + return 0; + } +} + +static int rockchip_spi_config(struct rockchip_spi *rs, + struct spi_device *spi, struct spi_transfer *xfer) +{ + u32 cr0 = CR0_FRF_SPI << CR0_FRF_OFFSET + | CR0_BHT_8BIT << CR0_BHT_OFFSET + | CR0_SSD_ONE << CR0_SSD_OFFSET + | CR0_EM_BIG << CR0_EM_OFFSET; + + cr0 |= rs->rsd << CR0_RSD_OFFSET; + cr0 |= (spi->mode & 0x3U) << CR0_SCPH_OFFSET; + if (spi->mode & SPI_LSB_FIRST) + cr0 |= CR0_FBM_LSB << CR0_FBM_OFFSET; + if (spi->mode & SPI_CS_HIGH) + cr0 |= BIT(spi_get_chipselect(spi, 0)) << CR0_SOI_OFFSET; + + if (xfer->rx_buf && xfer->tx_buf) + cr0 |= CR0_XFM_TR << CR0_XFM_OFFSET; + else if (xfer->rx_buf) + cr0 |= CR0_XFM_RO << CR0_XFM_OFFSET; + + cr0 |= CR0_XFM_TR << CR0_XFM_OFFSET; + + switch (xfer->bits_per_word) { + case 4: + cr0 |= CR0_DFS_4BIT << CR0_DFS_OFFSET; + break; + case 8: + cr0 |= CR0_DFS_8BIT << CR0_DFS_OFFSET; + break; + case 16: + cr0 |= CR0_DFS_16BIT << CR0_DFS_OFFSET; + break; + default: + /* we only whitelist 4, 8 and 16 bit words in + * ctlr->bits_per_word_mask, so this shouldn't + * happen + */ + dev_err(rs->dev, "unknown bits per word: %d\n", + xfer->bits_per_word); + return -EINVAL; + } + + writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0); + + /* the hardware only supports an even clock divisor, so + * round divisor = spiclk / speed up to nearest even number + * so that the resulting speed is <= the requested speed + */ + writel_relaxed(2 * DIV_ROUND_UP(rs->freq, 2 * xfer->speed_hz), + rs->regs + ROCKCHIP_SPI_BAUDR); + + return 0; +} + +static size_t rockchip_spi_max_transfer_size(struct spi_device *spi) +{ + return ROCKCHIP_SPI_MAX_TRANLEN; +} + +static int rockchip_spi_transfer_one( + struct rockchip_spi *rs, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + int ret; + + /* Zero length transfers won't trigger an interrupt on completion */ + if (!xfer->len) + return 1; + + if (!xfer->tx_buf && !xfer->rx_buf) { + dev_err(rs->dev, "No buffer for transfer\n"); + return -EINVAL; + } + + if (xfer->len > ROCKCHIP_SPI_MAX_TRANLEN) { + dev_err(rs->dev, "Transfer is too long (%d)\n", xfer->len); + return -EINVAL; + } + + ret = rockchip_spi_config(rs, spi, xfer); + if (ret) + return ret; + + spi_enable_chip(rs, true); + rockchip_spi_pio(rs, xfer); + spi_enable_chip(rs, false); + + return 0; +} + +static int rockchip_spi_transfer(struct spi_device *spi_dev, struct spi_message *msg) +{ + struct rockchip_spi *rs = spi_controller_get_devdata(spi_dev->controller); + struct spi_transfer *t; + int ret = 0; + + if (list_empty(&msg->transfers)) + return 0; + + rockchip_spi_set_cs(spi_dev, true); + + msg->actual_length = 0; + + list_for_each_entry(t, &msg->transfers, transfer_list) { + dev_dbg(rs->dev, " xfer %p: len %u tx %p rx %p\n", + t, t->len, t->tx_buf, t->rx_buf); + + ret = rockchip_spi_transfer_one(rs, spi_dev, t); + if (ret < 0) + goto out; + msg->actual_length += t->len; + } + +out: + rockchip_spi_set_cs(spi_dev, false); + return ret; +} + +static int rockchip_spi_setup(struct spi_device *spi) +{ + struct rockchip_spi *rs = spi_controller_get_devdata(spi->controller); + u32 cr0; + + if (!spi_get_csgpiod(spi, 0) && (spi->mode & SPI_CS_HIGH) && !rs->cs_high_supported) { + dev_warn(&spi->dev, "setup: non GPIO CS can't be active-high\n"); + return -EINVAL; + } + + cr0 = readl_relaxed(rs->regs + ROCKCHIP_SPI_CTRLR0); + + cr0 &= ~(0x3 << CR0_SCPH_OFFSET); + cr0 |= ((spi->mode & 0x3) << CR0_SCPH_OFFSET); + if (spi->mode & SPI_CS_HIGH && spi_get_chipselect(spi, 0) <= 1) + cr0 |= BIT(spi_get_chipselect(spi, 0)) << CR0_SOI_OFFSET; + else if (spi_get_chipselect(spi, 0) <= 1) + cr0 &= ~(BIT(spi_get_chipselect(spi, 0)) << CR0_SOI_OFFSET); + + writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0); + + return 0; +} + +static int rockchip_spi_probe(struct device *dev) +{ + int ret; + struct rockchip_spi *rs; + struct spi_controller *ctlr; + struct device_node *np = dev->of_node; + u32 rsd_nsecs, num_cs; + bool target_mode; + struct resource *iores; + + target_mode = of_property_read_bool(np, "spi-slave"); + if (target_mode) + return 0; + + rs = xzalloc(sizeof(*rs)); + ctlr = &rs->ctlr; + + /* Get basic io resource and map it */ + iores = dev_request_mem_resource(dev, 0); + if (IS_ERR(iores)) + return PTR_ERR(iores); + rs->regs = IOMEM(iores->start); + + rs->apb_pclk = clk_get_enabled(dev, "apb_pclk"); + if (IS_ERR(rs->apb_pclk)) { + dev_err(dev, "Failed to get apb_pclk\n"); + ret = PTR_ERR(rs->apb_pclk); + goto err_put_ctlr; + } + + rs->spiclk = clk_get_enabled(dev, "spiclk"); + if (IS_ERR(rs->spiclk)) { + dev_err(dev, "Failed to get spi_pclk\n"); + ret = PTR_ERR(rs->spiclk); + goto err_put_ctlr; + } + + spi_enable_chip(rs, false); + + rs->dev = dev; + rs->freq = clk_get_rate(rs->spiclk); + + if (!of_property_read_u32(np, "rx-sample-delay-ns", + &rsd_nsecs)) { + /* rx sample delay is expressed in parent clock cycles (max 3) */ + u32 rsd = DIV_ROUND_CLOSEST(rsd_nsecs * (rs->freq >> 8), + 1000000000 >> 8); + if (!rsd) { + dev_warn(rs->dev, "%u Hz are too slow to express %u ns delay\n", + rs->freq, rsd_nsecs); + } else if (rsd > CR0_RSD_MAX) { + rsd = CR0_RSD_MAX; + dev_warn(rs->dev, "%u Hz are too fast to express %u ns delay, clamping at %u ns\n", + rs->freq, rsd_nsecs, + CR0_RSD_MAX * 1000000000U / rs->freq); + } + rs->rsd = rsd; + } + + rs->fifo_len = get_fifo_len(rs); + if (!rs->fifo_len) { + dev_err(dev, "Failed to get fifo length\n"); + ret = -EINVAL; + goto err_put_ctlr; + } + +// ctlr->bus_num = pdev->id; +// ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_LSB_FIRST; + + /* + * rk spi0 has two native cs, spi1..5 one cs only + * if num-cs is missing in the dts, default to 1 + */ + num_cs = 1; + of_property_read_u32(np, "num-cs", &num_cs); + ctlr->num_chipselect = num_cs; + + ctlr->dev = dev; + ctlr->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8) | SPI_BPW_MASK(4); + ctlr->max_speed_hz = min(rs->freq / BAUDR_SCKDV_MIN, MAX_SCLK_OUT); + + ctlr->setup = rockchip_spi_setup; + ctlr->transfer = rockchip_spi_transfer; + ctlr->max_transfer_size = rockchip_spi_max_transfer_size; + + switch (readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION)) { + case ROCKCHIP_SPI_VER2_TYPE2: + rs->cs_high_supported = true; + break; + } + + spi_controller_set_devdata(ctlr, rs); + + ret = spi_register_controller(ctlr); + if (ret < 0) { + dev_err(dev, "Failed to register controller\n"); + goto err_free_dma_rx; + } + + return 0; + +err_free_dma_rx: +err_put_ctlr: + + return ret; +} + +static const struct of_device_id rockchip_spi_dt_match[] = { + { .compatible = "rockchip,px30-spi", }, + { .compatible = "rockchip,rk3036-spi", }, + { .compatible = "rockchip,rk3066-spi", }, + { .compatible = "rockchip,rk3188-spi", }, + { .compatible = "rockchip,rk3228-spi", }, + { .compatible = "rockchip,rk3288-spi", }, + { .compatible = "rockchip,rk3308-spi", }, + { .compatible = "rockchip,rk3328-spi", }, + { .compatible = "rockchip,rk3368-spi", }, + { .compatible = "rockchip,rk3399-spi", }, + { .compatible = "rockchip,rv1108-spi", }, + { .compatible = "rockchip,rv1126-spi", }, + { }, +}; +MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match); + +static struct driver rockchip_spi_driver = { + .name = DRIVER_NAME, + .probe = rockchip_spi_probe, + .of_compatible = rockchip_spi_dt_match, +}; +coredevice_platform_driver(rockchip_spi_driver); + +MODULE_AUTHOR("Addy Ke <addy.ke@xxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/spi/spi.h b/include/spi/spi.h index 45d6f5931c..0c60e99868 100644 --- a/include/spi/spi.h +++ b/include/spi/spi.h @@ -115,6 +115,13 @@ static inline struct spi_device *to_spi_device(struct device *dev) return dev ? container_of(dev, struct spi_device, dev) : NULL; } +static inline u8 spi_get_chipselect(const struct spi_device *spi, u8 idx) +{ + BUG_ON(idx != 0); + + return spi->chip_select; +} + struct spi_message; /** -- 2.39.5