/* * Copyright (c) 2010-2013 NVIDIA Corporation * With help from the mpc8xxx SPI driver * With more help from omap3_spi SPI driver * * SPDX-License-Identifier: GPL-2.0+ */ #include #include #include #include #include #include #include #include #include #include #include "tegra_spi.h" DECLARE_GLOBAL_DATA_PTR; #define SPI_CMD_GO BIT(30) #define SPI_CMD_ACTIVE_SCLK_SHIFT 26 #define SPI_CMD_ACTIVE_SCLK_MASK (3 << SPI_CMD_ACTIVE_SCLK_SHIFT) #define SPI_CMD_CK_SDA BIT(21) #define SPI_CMD_ACTIVE_SDA_SHIFT 18 #define SPI_CMD_ACTIVE_SDA_MASK (3 << SPI_CMD_ACTIVE_SDA_SHIFT) #define SPI_CMD_CS_POL BIT(16) #define SPI_CMD_TXEN BIT(15) #define SPI_CMD_RXEN BIT(14) #define SPI_CMD_CS_VAL BIT(13) #define SPI_CMD_CS_SOFT BIT(12) #define SPI_CMD_CS_DELAY BIT(9) #define SPI_CMD_CS3_EN BIT(8) #define SPI_CMD_CS2_EN BIT(7) #define SPI_CMD_CS1_EN BIT(6) #define SPI_CMD_CS0_EN BIT(5) #define SPI_CMD_BIT_LENGTH BIT(4) #define SPI_CMD_BIT_LENGTH_MASK GENMASK(4, 0) #define SPI_STAT_BSY BIT(31) #define SPI_STAT_RDY BIT(30) #define SPI_STAT_RXF_FLUSH BIT(29) #define SPI_STAT_TXF_FLUSH BIT(28) #define SPI_STAT_RXF_UNR BIT(27) #define SPI_STAT_TXF_OVF BIT(26) #define SPI_STAT_RXF_EMPTY BIT(25) #define SPI_STAT_RXF_FULL BIT(24) #define SPI_STAT_TXF_EMPTY BIT(23) #define SPI_STAT_TXF_FULL BIT(22) #define SPI_STAT_SEL_TXRX_N BIT(16) #define SPI_STAT_CUR_BLKCNT BIT(15) #define SPI_TIMEOUT 1000 #define TEGRA_SPI_MAX_FREQ 52000000 struct spi_regs { u32 command; /* SPI_COMMAND_0 register */ u32 status; /* SPI_STATUS_0 register */ u32 rx_cmp; /* SPI_RX_CMP_0 register */ u32 dma_ctl; /* SPI_DMA_CTL_0 register */ u32 tx_fifo; /* SPI_TX_FIFO_0 register */ u32 rsvd[3]; /* offsets 0x14 to 0x1F reserved */ u32 rx_fifo; /* SPI_RX_FIFO_0 register */ }; struct tegra20_sflash_priv { struct spi_regs *regs; unsigned int freq; unsigned int mode; int periph_id; int valid; int last_transaction_us; }; int tegra20_sflash_cs_info(struct udevice *bus, unsigned int cs, struct spi_cs_info *info) { /* Tegra20 SPI-Flash - only 1 device ('bus/cs') */ if (cs != 0) return -ENODEV; else return 0; } static int tegra20_sflash_ofdata_to_platdata(struct udevice *bus) { struct tegra_spi_platdata *plat = bus->platdata; const void *blob = gd->fdt_blob; int node = bus->of_offset; plat->base = dev_get_addr(bus); plat->periph_id = clock_decode_periph_id(blob, node); if (plat->periph_id == PERIPH_ID_NONE) { debug("%s: could not decode periph id %d\n", __func__, plat->periph_id); return -FDT_ERR_NOTFOUND; } /* Use 500KHz as a suitable default */ plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency", 500000); plat->deactivate_delay_us = fdtdec_get_int(blob, node, "spi-deactivate-delay", 0); debug("%s: base=%#08lx, periph_id=%d, max-frequency=%d, deactivate_delay=%d\n", __func__, plat->base, plat->periph_id, plat->frequency, plat->deactivate_delay_us); return 0; } static int tegra20_sflash_probe(struct udevice *bus) { struct tegra_spi_platdata *plat = dev_get_platdata(bus); struct tegra20_sflash_priv *priv = dev_get_priv(bus); priv->regs = (struct spi_regs *)plat->base; priv->last_transaction_us = timer_get_us(); priv->freq = plat->frequency; priv->periph_id = plat->periph_id; return 0; } static int tegra20_sflash_claim_bus(struct udevice *dev) { struct udevice *bus = dev->parent; struct tegra20_sflash_priv *priv = dev_get_priv(bus); struct spi_regs *regs = priv->regs; u32 reg; /* Change SPI clock to correct frequency, PLLP_OUT0 source */ clock_start_periph_pll(priv->periph_id, CLOCK_ID_PERIPH, priv->freq); /* Clear stale status here */ reg = SPI_STAT_RDY | SPI_STAT_RXF_FLUSH | SPI_STAT_TXF_FLUSH | \ SPI_STAT_RXF_UNR | SPI_STAT_TXF_OVF; writel(reg, ®s->status); debug("%s: STATUS = %08x\n", __func__, readl(®s->status)); /* * Use sw-controlled CS, so we can clock in data after ReadID, etc. */ reg = (priv->mode & 1) << SPI_CMD_ACTIVE_SDA_SHIFT; if (priv->mode & 2) reg |= 1 << SPI_CMD_ACTIVE_SCLK_SHIFT; clrsetbits_le32(®s->command, SPI_CMD_ACTIVE_SCLK_MASK | SPI_CMD_ACTIVE_SDA_MASK, SPI_CMD_CS_SOFT | reg); debug("%s: COMMAND = %08x\n", __func__, readl(®s->command)); /* * SPI pins on Tegra20 are muxed - change pinmux later due to UART * issue. */ pinmux_set_func(PMUX_PINGRP_GMD, PMUX_FUNC_SFLASH); pinmux_tristate_disable(PMUX_PINGRP_LSPI); pinmux_set_func(PMUX_PINGRP_GMC, PMUX_FUNC_SFLASH); return 0; } static void spi_cs_activate(struct udevice *dev) { struct udevice *bus = dev->parent; struct tegra_spi_platdata *pdata = dev_get_platdata(bus); struct tegra20_sflash_priv *priv = dev_get_priv(bus); /* If it's too soon to do another transaction, wait */ if (pdata->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 < pdata->deactivate_delay_us) udelay(pdata->deactivate_delay_us - delay_us); } /* CS is negated on Tegra, so drive a 1 to get a 0 */ setbits_le32(&priv->regs->command, SPI_CMD_CS_VAL); } static void spi_cs_deactivate(struct udevice *dev) { struct udevice *bus = dev->parent; struct tegra_spi_platdata *pdata = dev_get_platdata(bus); struct tegra20_sflash_priv *priv = dev_get_priv(bus); /* CS is negated on Tegra, so drive a 0 to get a 1 */ clrbits_le32(&priv->regs->command, SPI_CMD_CS_VAL); /* Remember time of this transaction so we can honour the bus delay */ if (pdata->deactivate_delay_us) priv->last_transaction_us = timer_get_us(); } static int tegra20_sflash_xfer(struct udevice *dev, unsigned int bitlen, const void *data_out, void *data_in, unsigned long flags) { struct udevice *bus = dev->parent; struct tegra20_sflash_priv *priv = dev_get_priv(bus); struct spi_regs *regs = priv->regs; u32 reg, tmpdout, tmpdin = 0; const u8 *dout = data_out; u8 *din = data_in; int num_bytes; int ret; debug("%s: slave %u:%u dout %p din %p bitlen %u\n", __func__, bus->seq, spi_chip_select(dev), dout, din, bitlen); if (bitlen % 8) return -1; num_bytes = bitlen / 8; ret = 0; reg = readl(®s->status); writel(reg, ®s->status); /* Clear all SPI events via R/W */ debug("spi_xfer entry: STATUS = %08x\n", reg); reg = readl(®s->command); reg |= SPI_CMD_TXEN | SPI_CMD_RXEN; writel(reg, ®s->command); debug("spi_xfer: COMMAND = %08x\n", readl(®s->command)); if (flags & SPI_XFER_BEGIN) spi_cs_activate(dev); /* handle data in 32-bit chunks */ while (num_bytes > 0) { int bytes; int is_read = 0; int tm, i; tmpdout = 0; bytes = (num_bytes > 4) ? 4 : num_bytes; if (dout != NULL) { for (i = 0; i < bytes; ++i) tmpdout = (tmpdout << 8) | dout[i]; } num_bytes -= bytes; if (dout) dout += bytes; clrsetbits_le32(®s->command, SPI_CMD_BIT_LENGTH_MASK, bytes * 8 - 1); writel(tmpdout, ®s->tx_fifo); setbits_le32(®s->command, SPI_CMD_GO); /* * Wait for SPI transmit FIFO to empty, or to time out. * The RX FIFO status will be read and cleared last */ for (tm = 0, is_read = 0; tm < SPI_TIMEOUT; ++tm) { u32 status; status = readl(®s->status); /* We can exit when we've had both RX and TX activity */ if (is_read && (status & SPI_STAT_TXF_EMPTY)) break; if ((status & (SPI_STAT_BSY | SPI_STAT_RDY)) != SPI_STAT_RDY) tm++; else if (!(status & SPI_STAT_RXF_EMPTY)) { tmpdin = readl(®s->rx_fifo); is_read = 1; /* swap bytes read in */ if (din != NULL) { for (i = bytes - 1; i >= 0; --i) { din[i] = tmpdin & 0xff; tmpdin >>= 8; } din += bytes; } } } if (tm >= SPI_TIMEOUT) ret = tm; /* clear ACK RDY, etc. bits */ writel(readl(®s->status), ®s->status); } if (flags & SPI_XFER_END) spi_cs_deactivate(dev); debug("spi_xfer: transfer ended. Value=%08x, status = %08x\n", tmpdin, readl(®s->status)); if (ret) { printf("spi_xfer: timeout during SPI transfer, tm %d\n", ret); return -1; } return 0; } static int tegra20_sflash_set_speed(struct udevice *bus, uint speed) { struct tegra_spi_platdata *plat = bus->platdata; struct tegra20_sflash_priv *priv = dev_get_priv(bus); if (speed > plat->frequency) speed = plat->frequency; priv->freq = speed; debug("%s: regs=%p, speed=%d\n", __func__, priv->regs, priv->freq); return 0; } static int tegra20_sflash_set_mode(struct udevice *bus, uint mode) { struct tegra20_sflash_priv *priv = dev_get_priv(bus); priv->mode = mode; debug("%s: regs=%p, mode=%d\n", __func__, priv->regs, priv->mode); return 0; } static const struct dm_spi_ops tegra20_sflash_ops = { .claim_bus = tegra20_sflash_claim_bus, .xfer = tegra20_sflash_xfer, .set_speed = tegra20_sflash_set_speed, .set_mode = tegra20_sflash_set_mode, .cs_info = tegra20_sflash_cs_info, }; static const struct udevice_id tegra20_sflash_ids[] = { { .compatible = "nvidia,tegra20-sflash" }, { } }; U_BOOT_DRIVER(tegra20_sflash) = { .name = "tegra20_sflash", .id = UCLASS_SPI, .of_match = tegra20_sflash_ids, .ops = &tegra20_sflash_ops, .ofdata_to_platdata = tegra20_sflash_ofdata_to_platdata, .platdata_auto_alloc_size = sizeof(struct tegra_spi_platdata), .priv_auto_alloc_size = sizeof(struct tegra20_sflash_priv), .probe = tegra20_sflash_probe, };