| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * (C) Copyright 2013 Xilinx, Inc. |
| * (C) Copyright 2015 Jagan Teki <jteki@openedev.com> |
| * |
| * Xilinx Zynq PS SPI controller driver (master mode only) |
| */ |
| |
| #include <common.h> |
| #include <dm.h> |
| #include <log.h> |
| #include <malloc.h> |
| #include <spi.h> |
| #include <time.h> |
| #include <asm/io.h> |
| #include <linux/delay.h> |
| |
| DECLARE_GLOBAL_DATA_PTR; |
| |
| /* zynq spi register bit masks ZYNQ_SPI_<REG>_<BIT>_MASK */ |
| #define ZYNQ_SPI_CR_MSA_MASK BIT(15) /* Manual start enb */ |
| #define ZYNQ_SPI_CR_MCS_MASK BIT(14) /* Manual chip select */ |
| #define ZYNQ_SPI_CR_CS_MASK GENMASK(13, 10) /* Chip select */ |
| #define ZYNQ_SPI_CR_BAUD_MASK GENMASK(5, 3) /* Baud rate div */ |
| #define ZYNQ_SPI_CR_CPHA_MASK BIT(2) /* Clock phase */ |
| #define ZYNQ_SPI_CR_CPOL_MASK BIT(1) /* Clock polarity */ |
| #define ZYNQ_SPI_CR_MSTREN_MASK BIT(0) /* Mode select */ |
| #define ZYNQ_SPI_IXR_RXNEMPTY_MASK BIT(4) /* RX_FIFO_not_empty */ |
| #define ZYNQ_SPI_IXR_TXOW_MASK BIT(2) /* TX_FIFO_not_full */ |
| #define ZYNQ_SPI_IXR_ALL_MASK GENMASK(6, 0) /* All IXR bits */ |
| #define ZYNQ_SPI_ENR_SPI_EN_MASK BIT(0) /* SPI Enable */ |
| |
| #define ZYNQ_SPI_CR_BAUD_MAX 8 /* Baud rate divisor max val */ |
| #define ZYNQ_SPI_CR_BAUD_SHIFT 3 /* Baud rate divisor shift */ |
| #define ZYNQ_SPI_CR_SS_SHIFT 10 /* Slave select shift */ |
| |
| #define ZYNQ_SPI_FIFO_DEPTH 128 |
| #ifndef CONFIG_SYS_ZYNQ_SPI_WAIT |
| #define CONFIG_SYS_ZYNQ_SPI_WAIT (CONFIG_SYS_HZ/100) /* 10 ms */ |
| #endif |
| |
| /* zynq spi register set */ |
| struct zynq_spi_regs { |
| u32 cr; /* 0x00 */ |
| u32 isr; /* 0x04 */ |
| u32 ier; /* 0x08 */ |
| u32 idr; /* 0x0C */ |
| u32 imr; /* 0x10 */ |
| u32 enr; /* 0x14 */ |
| u32 dr; /* 0x18 */ |
| u32 txdr; /* 0x1C */ |
| u32 rxdr; /* 0x20 */ |
| }; |
| |
| |
| /* zynq spi platform data */ |
| struct zynq_spi_platdata { |
| struct zynq_spi_regs *regs; |
| u32 frequency; /* input frequency */ |
| u32 speed_hz; |
| uint deactivate_delay_us; /* Delay to wait after deactivate */ |
| uint activate_delay_us; /* Delay to wait after activate */ |
| }; |
| |
| /* zynq spi priv */ |
| struct zynq_spi_priv { |
| struct zynq_spi_regs *regs; |
| u8 cs; |
| u8 mode; |
| ulong last_transaction_us; /* Time of last transaction end */ |
| u8 fifo_depth; |
| u32 freq; /* required frequency */ |
| }; |
| |
| static int zynq_spi_ofdata_to_platdata(struct udevice *bus) |
| { |
| struct zynq_spi_platdata *plat = bus->platdata; |
| const void *blob = gd->fdt_blob; |
| int node = dev_of_offset(bus); |
| |
| plat->regs = (struct zynq_spi_regs *)devfdt_get_addr(bus); |
| |
| /* FIXME: Use 250MHz as a suitable default */ |
| plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency", |
| 250000000); |
| plat->deactivate_delay_us = fdtdec_get_int(blob, node, |
| "spi-deactivate-delay", 0); |
| plat->activate_delay_us = fdtdec_get_int(blob, node, |
| "spi-activate-delay", 0); |
| plat->speed_hz = plat->frequency / 2; |
| |
| debug("%s: regs=%p max-frequency=%d\n", __func__, |
| plat->regs, plat->frequency); |
| |
| return 0; |
| } |
| |
| static void zynq_spi_init_hw(struct zynq_spi_priv *priv) |
| { |
| struct zynq_spi_regs *regs = priv->regs; |
| u32 confr; |
| |
| /* Disable SPI */ |
| confr = ZYNQ_SPI_ENR_SPI_EN_MASK; |
| writel(~confr, ®s->enr); |
| |
| /* Disable Interrupts */ |
| writel(ZYNQ_SPI_IXR_ALL_MASK, ®s->idr); |
| |
| /* Clear RX FIFO */ |
| while (readl(®s->isr) & |
| ZYNQ_SPI_IXR_RXNEMPTY_MASK) |
| readl(®s->rxdr); |
| |
| /* Clear Interrupts */ |
| writel(ZYNQ_SPI_IXR_ALL_MASK, ®s->isr); |
| |
| /* Manual slave select and Auto start */ |
| confr = ZYNQ_SPI_CR_MCS_MASK | ZYNQ_SPI_CR_CS_MASK | |
| ZYNQ_SPI_CR_MSTREN_MASK; |
| confr &= ~ZYNQ_SPI_CR_MSA_MASK; |
| writel(confr, ®s->cr); |
| |
| /* Enable SPI */ |
| writel(ZYNQ_SPI_ENR_SPI_EN_MASK, ®s->enr); |
| } |
| |
| static int zynq_spi_probe(struct udevice *bus) |
| { |
| struct zynq_spi_platdata *plat = dev_get_platdata(bus); |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| |
| priv->regs = plat->regs; |
| priv->fifo_depth = ZYNQ_SPI_FIFO_DEPTH; |
| |
| /* init the zynq spi hw */ |
| zynq_spi_init_hw(priv); |
| |
| return 0; |
| } |
| |
| static void spi_cs_activate(struct udevice *dev) |
| { |
| struct udevice *bus = dev->parent; |
| struct zynq_spi_platdata *plat = bus->platdata; |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| struct zynq_spi_regs *regs = priv->regs; |
| u32 cr; |
| |
| /* If it's too soon to do another transaction, wait */ |
| if (plat->deactivate_delay_us && priv->last_transaction_us) { |
| ulong delay_us; /* The delay completed so far */ |
| delay_us = timer_get_us() - priv->last_transaction_us; |
| if (delay_us < plat->deactivate_delay_us) |
| udelay(plat->deactivate_delay_us - delay_us); |
| } |
| |
| clrbits_le32(®s->cr, ZYNQ_SPI_CR_CS_MASK); |
| cr = readl(®s->cr); |
| /* |
| * CS cal logic: CS[13:10] |
| * xxx0 - cs0 |
| * xx01 - cs1 |
| * x011 - cs2 |
| */ |
| cr |= (~(1 << priv->cs) << ZYNQ_SPI_CR_SS_SHIFT) & ZYNQ_SPI_CR_CS_MASK; |
| writel(cr, ®s->cr); |
| |
| if (plat->activate_delay_us) |
| udelay(plat->activate_delay_us); |
| } |
| |
| static void spi_cs_deactivate(struct udevice *dev) |
| { |
| struct udevice *bus = dev->parent; |
| struct zynq_spi_platdata *plat = bus->platdata; |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| struct zynq_spi_regs *regs = priv->regs; |
| |
| setbits_le32(®s->cr, ZYNQ_SPI_CR_CS_MASK); |
| |
| /* Remember time of this transaction so we can honour the bus delay */ |
| if (plat->deactivate_delay_us) |
| priv->last_transaction_us = timer_get_us(); |
| } |
| |
| static int zynq_spi_claim_bus(struct udevice *dev) |
| { |
| struct udevice *bus = dev->parent; |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| struct zynq_spi_regs *regs = priv->regs; |
| |
| writel(ZYNQ_SPI_ENR_SPI_EN_MASK, ®s->enr); |
| |
| return 0; |
| } |
| |
| static int zynq_spi_release_bus(struct udevice *dev) |
| { |
| struct udevice *bus = dev->parent; |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| struct zynq_spi_regs *regs = priv->regs; |
| u32 confr; |
| |
| confr = ZYNQ_SPI_ENR_SPI_EN_MASK; |
| writel(~confr, ®s->enr); |
| |
| return 0; |
| } |
| |
| static int zynq_spi_xfer(struct udevice *dev, unsigned int bitlen, |
| const void *dout, void *din, unsigned long flags) |
| { |
| struct udevice *bus = dev->parent; |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| struct zynq_spi_regs *regs = priv->regs; |
| struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev); |
| u32 len = bitlen / 8; |
| u32 tx_len = len, rx_len = len, tx_tvl; |
| const u8 *tx_buf = dout; |
| u8 *rx_buf = din, buf; |
| u32 ts, status; |
| |
| debug("spi_xfer: bus:%i cs:%i bitlen:%i len:%i flags:%lx\n", |
| bus->seq, slave_plat->cs, bitlen, len, flags); |
| |
| if (bitlen % 8) { |
| debug("spi_xfer: Non byte aligned SPI transfer\n"); |
| return -1; |
| } |
| |
| priv->cs = slave_plat->cs; |
| if (flags & SPI_XFER_BEGIN) |
| spi_cs_activate(dev); |
| |
| while (rx_len > 0) { |
| /* Write the data into TX FIFO - tx threshold is fifo_depth */ |
| tx_tvl = 0; |
| while ((tx_tvl < priv->fifo_depth) && tx_len) { |
| if (tx_buf) |
| buf = *tx_buf++; |
| else |
| buf = 0; |
| writel(buf, ®s->txdr); |
| tx_len--; |
| tx_tvl++; |
| } |
| |
| /* Check TX FIFO completion */ |
| ts = get_timer(0); |
| status = readl(®s->isr); |
| while (!(status & ZYNQ_SPI_IXR_TXOW_MASK)) { |
| if (get_timer(ts) > CONFIG_SYS_ZYNQ_SPI_WAIT) { |
| printf("spi_xfer: Timeout! TX FIFO not full\n"); |
| return -1; |
| } |
| status = readl(®s->isr); |
| } |
| |
| /* Read the data from RX FIFO */ |
| status = readl(®s->isr); |
| while ((status & ZYNQ_SPI_IXR_RXNEMPTY_MASK) && rx_len) { |
| buf = readl(®s->rxdr); |
| if (rx_buf) |
| *rx_buf++ = buf; |
| status = readl(®s->isr); |
| rx_len--; |
| } |
| } |
| |
| if (flags & SPI_XFER_END) |
| spi_cs_deactivate(dev); |
| |
| return 0; |
| } |
| |
| static int zynq_spi_set_speed(struct udevice *bus, uint speed) |
| { |
| struct zynq_spi_platdata *plat = bus->platdata; |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| struct zynq_spi_regs *regs = priv->regs; |
| uint32_t confr; |
| u8 baud_rate_val = 0; |
| |
| if (speed > plat->frequency) |
| speed = plat->frequency; |
| |
| /* Set the clock frequency */ |
| confr = readl(®s->cr); |
| if (speed == 0) { |
| /* Set baudrate x8, if the freq is 0 */ |
| baud_rate_val = 0x2; |
| } else if (plat->speed_hz != speed) { |
| while ((baud_rate_val < ZYNQ_SPI_CR_BAUD_MAX) && |
| ((plat->frequency / |
| (2 << baud_rate_val)) > speed)) |
| baud_rate_val++; |
| plat->speed_hz = speed / (2 << baud_rate_val); |
| } |
| confr &= ~ZYNQ_SPI_CR_BAUD_MASK; |
| confr |= (baud_rate_val << ZYNQ_SPI_CR_BAUD_SHIFT); |
| |
| writel(confr, ®s->cr); |
| priv->freq = speed; |
| |
| debug("zynq_spi_set_speed: regs=%p, speed=%d\n", |
| priv->regs, priv->freq); |
| |
| return 0; |
| } |
| |
| static int zynq_spi_set_mode(struct udevice *bus, uint mode) |
| { |
| struct zynq_spi_priv *priv = dev_get_priv(bus); |
| struct zynq_spi_regs *regs = priv->regs; |
| uint32_t confr; |
| |
| /* Set the SPI Clock phase and polarities */ |
| confr = readl(®s->cr); |
| confr &= ~(ZYNQ_SPI_CR_CPHA_MASK | ZYNQ_SPI_CR_CPOL_MASK); |
| |
| if (mode & SPI_CPHA) |
| confr |= ZYNQ_SPI_CR_CPHA_MASK; |
| if (mode & SPI_CPOL) |
| confr |= ZYNQ_SPI_CR_CPOL_MASK; |
| |
| writel(confr, ®s->cr); |
| priv->mode = mode; |
| |
| debug("zynq_spi_set_mode: regs=%p, mode=%d\n", priv->regs, priv->mode); |
| |
| return 0; |
| } |
| |
| static const struct dm_spi_ops zynq_spi_ops = { |
| .claim_bus = zynq_spi_claim_bus, |
| .release_bus = zynq_spi_release_bus, |
| .xfer = zynq_spi_xfer, |
| .set_speed = zynq_spi_set_speed, |
| .set_mode = zynq_spi_set_mode, |
| }; |
| |
| static const struct udevice_id zynq_spi_ids[] = { |
| { .compatible = "xlnx,zynq-spi-r1p6" }, |
| { .compatible = "cdns,spi-r1p6" }, |
| { } |
| }; |
| |
| U_BOOT_DRIVER(zynq_spi) = { |
| .name = "zynq_spi", |
| .id = UCLASS_SPI, |
| .of_match = zynq_spi_ids, |
| .ops = &zynq_spi_ops, |
| .ofdata_to_platdata = zynq_spi_ofdata_to_platdata, |
| .platdata_auto_alloc_size = sizeof(struct zynq_spi_platdata), |
| .priv_auto_alloc_size = sizeof(struct zynq_spi_priv), |
| .probe = zynq_spi_probe, |
| }; |