Zynq qspinor controller is works similar way as generic spi controller with additional features that make this controller work more specific to flash chips as salve devices.
Why, zynq qspi written as spi-nor controller driver.
(1) dual flash: This describes two/dual memories are connected with a single chip select line from a controller like dual stack and dual parallel connections see doc/SPI/README.dual-flash for more details.
Adding this support to spi-nor core looks quite managable and other generic code might effect and more over this is controller specific.
Signed-off-by: Jagan Teki jagan@openedev.com --- drivers/mtd/spi-nor/Makefile | 3 + drivers/mtd/spi-nor/zynq_qspinor.c | 641 +++++++++++++++++++++++++++++++++++++ 2 files changed, 644 insertions(+) create mode 100644 drivers/mtd/spi-nor/zynq_qspinor.c
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile index d11ccf4..bbaeee0 100644 --- a/drivers/mtd/spi-nor/Makefile +++ b/drivers/mtd/spi-nor/Makefile @@ -10,3 +10,6 @@ endif
## spi-nor to spi interface driver obj-$(CONFIG_MTD_M25P80) += m25p80.o + +## spi-nor drivers +obj-$(CONFIG_MTD_ZYNQ_QSPI) += zynq_qspinor.o diff --git a/drivers/mtd/spi-nor/zynq_qspinor.c b/drivers/mtd/spi-nor/zynq_qspinor.c new file mode 100644 index 0000000..c04e87a --- /dev/null +++ b/drivers/mtd/spi-nor/zynq_qspinor.c @@ -0,0 +1,641 @@ +/* + * (C) Copyright 2016 Jagan Teki jagan@openedev.com + * + * Xilinx Zynq Quad-SPI(QSPI) NOR controller driver + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <malloc.h> +#include <mtd.h> +#include <asm/io.h> + +#include <linux/mtd/mtd.h> +#include <linux/mtd/spi-nor.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* zynq qspi register bit masks ZYNQ_QSPI_<REG>_<BIT>_MASK */ +#define ZYNQ_QSPI_CR_IFMODE_MASK BIT(31) /* Flash intrface mode*/ +#define ZYNQ_QSPI_CR_MSA_MASK BIT(15) /* Manual start enb */ +#define ZYNQ_QSPI_CR_MCS_MASK BIT(14) /* Manual chip select */ +#define ZYNQ_QSPI_CR_PCS_MASK BIT(10) /* Peri chip select */ +#define ZYNQ_QSPI_CR_FW_MASK GENMASK(7, 6) /* FIFO width */ +#define ZYNQ_QSPI_CR_SS_MASK GENMASK(13, 10) /* Slave Select */ +#define ZYNQ_QSPI_CR_BAUD_MASK GENMASK(5, 3) /* Baud rate div */ +#define ZYNQ_QSPI_CR_CPHA_MASK BIT(2) /* Clock phase */ +#define ZYNQ_QSPI_CR_CPOL_MASK BIT(1) /* Clock polarity */ +#define ZYNQ_QSPI_CR_MSTREN_MASK BIT(0) /* Mode select */ +#define ZYNQ_QSPI_IXR_RXNEMPTY_MASK BIT(4) /* RX_FIFO_not_empty */ +#define ZYNQ_QSPI_IXR_TXOW_MASK BIT(2) /* TX_FIFO_not_full */ +#define ZYNQ_QSPI_IXR_ALL_MASK GENMASK(6, 0) /* All IXR bits */ +#define ZYNQ_QSPI_ENR_SPI_EN_MASK BIT(0) /* SPI Enable */ +#define ZYNQ_QSPI_LQSPICFG_LQMODE_MASK BIT(31) /* Linear QSPI Mode */ + +/* zynq qspi Transmit Data Register */ +#define ZYNQ_QSPI_TXD_00_00_OFFSET 0x1C /* Transmit 4-byte inst */ +#define ZYNQ_QSPI_TXD_00_01_OFFSET 0x80 /* Transmit 1-byte inst */ +#define ZYNQ_QSPI_TXD_00_10_OFFSET 0x84 /* Transmit 2-byte inst */ +#define ZYNQ_QSPI_TXD_00_11_OFFSET 0x88 /* Transmit 3-byte inst */ + +#define ZYNQ_QSPI_XFER_BEGIN BIT(0) +#define ZYNQ_QSPI_XFER_END BIT(1) +#define ZYNQ_QSPI_TXFIFO_THRESHOLD 1 /* Tx FIFO threshold level*/ +#define ZYNQ_QSPI_RXFIFO_THRESHOLD 32 /* Rx FIFO threshold level */ + +#define ZYNQ_QSPI_CR_BAUD_MAX 8 /* Baud rate divisor max val */ +#define ZYNQ_QSPI_CR_BAUD_SHIFT 3 /* Baud rate divisor shift */ +#define ZYNQ_QSPI_CR_SS_SHIFT 10 /* Slave select shift */ +#define ZYNQ_QSPI_MAX_CMDSZ 4 /* 1 byte opcode,3 byte addr */ + +#define ZYNQ_QSPI_FIFO_DEPTH 63 +#ifndef CONFIG_SYS_ZYNQ_QSPI_WAIT +#define CONFIG_SYS_ZYNQ_QSPI_WAIT CONFIG_SYS_HZ/100 /* 10 ms */ +#endif + +/* zynq qspi register set */ +struct zynq_qspinor_regs { + u32 cr; /* 0x00 */ + u32 isr; /* 0x04 */ + u32 ier; /* 0x08 */ + u32 idr; /* 0x0C */ + u32 imr; /* 0x10 */ + u32 enr; /* 0x14 */ + u32 dr; /* 0x18 */ + u32 txd0r; /* 0x1C */ + u32 drxr; /* 0x20 */ + u32 sicr; /* 0x24 */ + u32 txftr; /* 0x28 */ + u32 rxftr; /* 0x2C */ + u32 gpior; /* 0x30 */ + u32 reserved0[19]; + u32 txd1r; /* 0x80 */ + u32 txd2r; /* 0x84 */ + u32 txd3r; /* 0x88 */ + u32 reserved1[5]; + u32 lqspicfg; /* 0xA0 */ + u32 lqspists; /* 0xA4 */ +}; + +/* zynq qspi platform data */ +struct zynq_qspinor_platdata { + struct zynq_qspinor_regs *regs; + u32 frequency; /* input frequency */ + u32 speed_hz; +}; + +/* zynq qspi priv */ +struct zynq_qspinor_priv { + struct zynq_qspinor_regs *regs; + struct spi_nor spi_nor; + u8 cs; + u8 mode; + u8 fifo_depth; + u32 freq; /* required frequency */ + u8 cmd[4]; /* 1 byte opcode + 3-byte address */ + const void *tx_buf; + void *rx_buf; + unsigned len; + int bytes_to_transfer; + int bytes_to_receive; + unsigned int is_inst; + unsigned cs_change:1; +}; + +static void zynq_qspinor_addr(u32 addr, u8 *cmd) +{ + /* opcode is in cmd[0] */ + cmd[1] = addr >> 16; + cmd[2] = addr >> 8; + cmd[3] = addr >> 0; +} + +/* + * zynq_qspinor_read_data - Copy data to RX buffer + * @zqspi: Pointer to the zynq_qspinor structure + * @data: The 32 bit variable where data is stored + * @size: Number of bytes to be copied from data to RX buffer + */ +static void zynq_qspinor_read_data(struct zynq_qspinor_priv *priv, + u32 data, u8 size) +{ + u8 byte3; + + debug("%s: data 0x%04x rx_buf addr: 0x%08x size %d\n", __func__ , + data, (unsigned)(priv->rx_buf), size); + + if (priv->rx_buf) { + switch (size) { + case 1: + *((u8 *)priv->rx_buf) = data; + priv->rx_buf += 1; + break; + case 2: + *((u16 *)priv->rx_buf) = data; + priv->rx_buf += 2; + break; + case 3: + *((u16 *)priv->rx_buf) = data; + priv->rx_buf += 2; + byte3 = (u8)(data >> 16); + *((u8 *)priv->rx_buf) = byte3; + priv->rx_buf += 1; + break; + case 4: + /* Can not assume word aligned buffer */ + memcpy(priv->rx_buf, &data, size); + priv->rx_buf += 4; + break; + default: + /* This will never execute */ + break; + } + } + priv->bytes_to_receive -= size; + if (priv->bytes_to_receive < 0) + priv->bytes_to_receive = 0; +} + +/* + * zynq_qspinor_write_data - Copy data from TX buffer + * @zqspi: Pointer to the zynq_qspinor structure + * @data: Pointer to the 32 bit variable where data is to be copied + * @size: Number of bytes to be copied from TX buffer to data + */ +static void zynq_qspinor_write_data(struct zynq_qspinor_priv *priv, + u32 *data, u8 size) +{ + if (priv->tx_buf) { + switch (size) { + case 1: + *data = *((u8 *)priv->tx_buf); + priv->tx_buf += 1; + *data |= 0xFFFFFF00; + break; + case 2: + *data = *((u16 *)priv->tx_buf); + priv->tx_buf += 2; + *data |= 0xFFFF0000; + break; + case 3: + *data = *((u16 *)priv->tx_buf); + priv->tx_buf += 2; + *data |= (*((u8 *)priv->tx_buf) << 16); + priv->tx_buf += 1; + *data |= 0xFF000000; + break; + case 4: + /* Can not assume word aligned buffer */ + memcpy(data, priv->tx_buf, size); + priv->tx_buf += 4; + break; + default: + /* This will never execute */ + break; + } + } else { + *data = 0; + } + + debug("%s: data 0x%08x tx_buf addr: 0x%08x size %d\n", __func__, + *data, (u32)priv->tx_buf, size); + + priv->bytes_to_transfer -= size; + if (priv->bytes_to_transfer < 0) + priv->bytes_to_transfer = 0; +} + +static void zynq_qspinor_chipselect(struct zynq_qspinor_priv *priv, int is_on) +{ + u32 confr; + struct zynq_qspinor_regs *regs = priv->regs; + + confr = readl(®s->cr); + + if (is_on) { + /* Select the slave */ + confr &= ~ZYNQ_QSPI_CR_SS_MASK; + confr |= (~(1 << priv->cs) << ZYNQ_QSPI_CR_SS_SHIFT) & + ZYNQ_QSPI_CR_SS_MASK; + } else + /* Deselect the slave */ + confr |= ZYNQ_QSPI_CR_SS_MASK; + + writel(confr, ®s->cr); +} + +/* + * zynq_qspinor_fill_tx_fifo - Fills the TX FIFO with as many bytes as possible + * @zqspi: Pointer to the zynq_qspinor structure + */ +static void zynq_qspinor_fill_tx_fifo(struct zynq_qspinor_priv *priv, u32 size) +{ + u32 data = 0; + u32 fifocount = 0; + unsigned len, offset; + struct zynq_qspinor_regs *regs = priv->regs; + static const unsigned offsets[4] = { + ZYNQ_QSPI_TXD_00_00_OFFSET, ZYNQ_QSPI_TXD_00_01_OFFSET, + ZYNQ_QSPI_TXD_00_10_OFFSET, ZYNQ_QSPI_TXD_00_11_OFFSET }; + + while ((fifocount < size) && + (priv->bytes_to_transfer > 0)) { + if (priv->bytes_to_transfer >= 4) { + if (priv->tx_buf) { + memcpy(&data, priv->tx_buf, 4); + priv->tx_buf += 4; + } else { + data = 0; + } + writel(data, ®s->txd0r); + priv->bytes_to_transfer -= 4; + fifocount++; + } else { + /* Write TXD1, TXD2, TXD3 only if TxFIFO is empty. */ + if (!(readl(®s->isr) + & ZYNQ_QSPI_IXR_TXOW_MASK) && + !priv->rx_buf) + return; + len = priv->bytes_to_transfer; + zynq_qspinor_write_data(priv, &data, len); + offset = (priv->rx_buf) ? offsets[0] : offsets[len]; + writel(data, ®s->cr + (offset / 4)); + } + } +} + +/* + * zynq_qspinor_irq_poll - Interrupt service routine of the QSPI controller + * @zqspi: Pointer to the zynq_qspinor structure + * + * This function handles TX empty and Mode Fault interrupts only. + * On TX empty interrupt this function reads the received data from RX FIFO and + * fills the TX FIFO if there is any data remaining to be transferred. + * On Mode Fault interrupt this function indicates that transfer is completed, + * the SPI subsystem will identify the error as the remaining bytes to be + * transferred is non-zero. + * + * returns: 0 for poll timeout + * 1 transfer operation complete + */ +static int zynq_qspinor_irq_poll(struct zynq_qspinor_priv *priv) +{ + struct zynq_qspinor_regs *regs = priv->regs; + u32 rxindex = 0; + u32 rxcount; + u32 status, timeout; + + /* Poll until any of the interrupt status bits are set */ + timeout = get_timer(0); + do { + status = readl(®s->isr); + } while ((status == 0) && + (get_timer(timeout) < CONFIG_SYS_ZYNQ_QSPI_WAIT)); + + if (status == 0) { + printf("zynq_qspinor_irq_poll: Timeout!\n"); + return -ETIMEDOUT; + } + + writel(status, ®s->isr); + + /* Disable all interrupts */ + writel(ZYNQ_QSPI_IXR_ALL_MASK, ®s->idr); + if ((status & ZYNQ_QSPI_IXR_TXOW_MASK) || + (status & ZYNQ_QSPI_IXR_RXNEMPTY_MASK)) { + /* + * This bit is set when Tx FIFO has < THRESHOLD entries. We have + * the THRESHOLD value set to 1, so this bit indicates Tx FIFO + * is empty + */ + rxcount = priv->bytes_to_receive - priv->bytes_to_transfer; + rxcount = (rxcount % 4) ? ((rxcount/4)+1) : (rxcount/4); + while ((rxindex < rxcount) && + (rxindex < ZYNQ_QSPI_RXFIFO_THRESHOLD)) { + /* Read out the data from the RX FIFO */ + u32 data; + data = readl(®s->drxr); + + if (priv->bytes_to_receive >= 4) { + if (priv->rx_buf) { + memcpy(priv->rx_buf, &data, 4); + priv->rx_buf += 4; + } + priv->bytes_to_receive -= 4; + } else { + zynq_qspinor_read_data(priv, data, + priv->bytes_to_receive); + } + rxindex++; + } + + if (priv->bytes_to_transfer) { + /* There is more data to send */ + zynq_qspinor_fill_tx_fifo(priv, + ZYNQ_QSPI_RXFIFO_THRESHOLD); + + writel(ZYNQ_QSPI_IXR_ALL_MASK, ®s->ier); + } else { + /* + * If transfer and receive is completed then only send + * complete signal + */ + if (!priv->bytes_to_receive) { + /* return operation complete */ + writel(ZYNQ_QSPI_IXR_ALL_MASK, + ®s->idr); + return 1; + } + } + } + + return 0; +} + +/* + * zynq_qspinor_start_transfer - Initiates the QSPI transfer + * @qspi: Pointer to the spi_device structure + * @transfer: Pointer to the spi_transfer structure which provide information + * about next transfer parameters + * + * This function fills the TX FIFO, starts the QSPI transfer, and waits for the + * transfer to be completed. + * + * returns: Number of bytes transferred in the last transfer + */ +static int zynq_qspinor_start_transfer(struct zynq_qspinor_priv *priv) +{ + u32 data = 0; + struct zynq_qspinor_regs *regs = priv->regs; + + debug("%s: qspi: 0x%08x transfer: 0x%08x len: %d\n", __func__, + (u32)priv, (u32)priv, priv->len); + + priv->bytes_to_transfer = priv->len; + priv->bytes_to_receive = priv->len; + + if (priv->len < 4) + zynq_qspinor_fill_tx_fifo(priv, priv->len); + else + zynq_qspinor_fill_tx_fifo(priv, priv->fifo_depth); + + writel(ZYNQ_QSPI_IXR_ALL_MASK, ®s->ier); + + /* wait for completion */ + do { + data = zynq_qspinor_irq_poll(priv); + } while (data == 0); + + return (priv->len) - (priv->bytes_to_transfer); +} + +static int zynq_qspinor_transfer(struct zynq_qspinor_priv *priv) +{ + unsigned cs_change = 1; + int status = 0; + + while (1) { + /* Select the chip if required */ + if (cs_change) + zynq_qspinor_chipselect(priv, 1); + + cs_change = priv->cs_change; + + if (!priv->tx_buf && !priv->rx_buf && priv->len) { + status = -1; + break; + } + + /* Request the transfer */ + if (priv->len) { + status = zynq_qspinor_start_transfer(priv); + priv->is_inst = 0; + } + + if (status != priv->len) { + if (status > 0) + status = -EMSGSIZE; + debug("zynq_qspinor_transfer:%d len:%d\n", + status, priv->len); + break; + } + status = 0; + + if (cs_change) + /* Deselect the chip */ + zynq_qspinor_chipselect(priv, 0); + + break; + } + + return 0; +} + +static int zynq_qspinor_xfer(struct spi_nor *nor, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct zynq_qspinor_priv *priv = nor->priv; + + priv->tx_buf = dout; + priv->rx_buf = din; + priv->len = bitlen / 8; + + /* + * Festering sore. + * Assume that the beginning of a transfer with bits to + * transmit must contain a device command. + */ + if (dout && flags & ZYNQ_QSPI_XFER_BEGIN) + priv->is_inst = 1; + else + priv->is_inst = 0; + + if (flags & ZYNQ_QSPI_XFER_END) + priv->cs_change = 1; + else + priv->cs_change = 0; + + zynq_qspinor_transfer(priv); + + return 0; +} + +static int zynq_qspinor_tx_then_rx(struct spi_nor *nor, const u8 *opcode, + size_t n_opcode, const u8 *txbuf, + u8 *rxbuf, size_t n_buf) +{ + struct zynq_qspinor_priv *priv = nor->priv; + struct zynq_qspinor_regs *regs = priv->regs; + unsigned long flags = ZYNQ_QSPI_XFER_BEGIN; + int ret; + + /* enable spi */ + writel(ZYNQ_QSPI_ENR_SPI_EN_MASK, ®s->enr); + + if (n_buf == 0) + flags |= ZYNQ_QSPI_XFER_END; + + ret = zynq_qspinor_xfer(nor, n_opcode * 8, opcode, NULL, flags); + if (ret) { + debug("%s: failed to send command (%zu bytes): %d\n", + __func__, n_opcode, ret); + } else if (n_buf != 0) { + ret = zynq_qspinor_xfer(nor, n_buf * 8, txbuf, rxbuf, + ZYNQ_QSPI_XFER_END); + if (ret) + debug("%s: failed to transfer %zu bytes of data: %d\n", + __func__, n_buf, ret); + } + + /* disable spi */ + writel(~ZYNQ_QSPI_ENR_SPI_EN_MASK, ®s->enr); + + return ret; +} + +static int zynq_qspinor_read_reg(struct spi_nor *nor, u8 opcode, + u8 *val, int len) +{ + return zynq_qspinor_tx_then_rx(nor, &opcode, 1, NULL, val, len); +} + +static int zynq_qspinor_write_reg(struct spi_nor *nor, u8 opcode, + u8 *buf, int len) +{ + return zynq_qspinor_tx_then_rx(nor, &opcode, 1, buf, NULL, len); +} + +static int zynq_qspinor_read(struct spi_nor *nor, loff_t from, + size_t len, u_char *buf) +{ + struct zynq_qspinor_priv *priv = nor->priv; + unsigned int cmd_sz = sizeof(priv->cmd) + (nor->read_dummy / 8); + + priv->cmd[0] = nor->read_opcode; + zynq_qspinor_addr(from, priv->cmd); + + return zynq_qspinor_tx_then_rx(nor, priv->cmd, cmd_sz, NULL, buf, len); +} + +static int zynq_qspinor_write(struct spi_nor *nor, loff_t to, + size_t len, const u_char *buf) +{ + struct zynq_qspinor_priv *priv = nor->priv; + + priv->cmd[0] = nor->program_opcode; + if (buf == NULL) + priv->cmd[0] = nor->erase_opcode; + + zynq_qspinor_addr(to, priv->cmd); + + return zynq_qspinor_tx_then_rx(nor, priv->cmd, sizeof(priv->cmd), + buf, NULL, len); +} + +static void zynq_qspinor_init_hw(struct zynq_qspinor_priv *priv) +{ + struct zynq_qspinor_regs *regs = priv->regs; + u32 confr; + + /* disable QSPI */ + writel(~ZYNQ_QSPI_ENR_SPI_EN_MASK, ®s->enr); + + /* disable Interrupts */ + writel(ZYNQ_QSPI_IXR_ALL_MASK, ®s->idr); + + /* dlear the TX and RX threshold reg */ + writel(ZYNQ_QSPI_TXFIFO_THRESHOLD, ®s->txftr); + writel(ZYNQ_QSPI_RXFIFO_THRESHOLD, ®s->rxftr); + + /* clear the RX FIFO */ + while (readl(®s->isr) & ZYNQ_QSPI_IXR_RXNEMPTY_MASK) + readl(®s->drxr); + + /* clear Interrupts */ + writel(ZYNQ_QSPI_IXR_ALL_MASK, ®s->isr); + + /* manual slave select and Auto start */ + confr = readl(®s->cr); + confr &= ~ZYNQ_QSPI_CR_MSA_MASK; + confr |= ZYNQ_QSPI_CR_IFMODE_MASK | ZYNQ_QSPI_CR_MCS_MASK | + ZYNQ_QSPI_CR_PCS_MASK | ZYNQ_QSPI_CR_FW_MASK | + ZYNQ_QSPI_CR_MSTREN_MASK; + writel(confr, ®s->cr); + + /* enable SPI */ + writel(ZYNQ_QSPI_ENR_SPI_EN_MASK, ®s->enr); +} + +static int zynq_qspinor_ofdata_to_platdata(struct udevice *bus) +{ + struct zynq_qspinor_platdata *plat = bus->platdata; + const void *blob = gd->fdt_blob; + int node = bus->of_offset; + + plat->regs = (struct zynq_qspinor_regs *)fdtdec_get_addr(blob, + node, "reg"); + + /* FIXME: Use 166MHz as a suitable default */ + plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency", + 166666666); + plat->speed_hz = plat->frequency / 2; + + debug("%s: regs=%p max-frequency=%d\n", __func__, + plat->regs, plat->frequency); + + return 0; +} + +static int zynq_qspinor_probe(struct udevice *dev) +{ + struct mtd_info *mtd = mtd_get_info(dev); + struct zynq_qspinor_platdata *plat = dev_get_platdata(dev); + struct zynq_qspinor_priv *priv = dev_get_priv(dev); + struct spi_nor *nor; + int ret; + + nor = &priv->spi_nor; + + nor->priv = priv; + mtd->priv = nor; + nor->dev = dev; + + priv->regs = plat->regs; + priv->fifo_depth = ZYNQ_QSPI_FIFO_DEPTH; + + /* install the hooks */ + nor->read = zynq_qspinor_read; + nor->write = zynq_qspinor_write; + nor->read_reg = zynq_qspinor_read_reg; + nor->write_reg = zynq_qspinor_write_reg; + + /* init the zynq spi hw */ + zynq_qspinor_init_hw(priv); + + ret = spi_nor_scan(dev); + if (ret) + return -EINVAL; + + ret = dm_add_mtd_device(dev); + if (ret) + return ret; + + return ret; +} + +static const struct udevice_id zynq_qspinor_ids[] = { + { .compatible = "xlnx,zynq-qspinor-1.0" }, + { } +}; + +U_BOOT_DRIVER(zynq_qspinor) = { + .name = "zynq_qspinor", + .id = UCLASS_MTD, + .of_match = zynq_qspinor_ids, + .ofdata_to_platdata = zynq_qspinor_ofdata_to_platdata, + .platdata_auto_alloc_size = sizeof(struct zynq_qspinor_platdata), + .priv_auto_alloc_size = sizeof(struct zynq_qspinor_priv), + .probe = zynq_qspinor_probe, +};