diff options
Diffstat (limited to 'roms/u-boot/drivers/spi/tegra114_spi.c')
| -rw-r--r-- | roms/u-boot/drivers/spi/tegra114_spi.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/spi/tegra114_spi.c b/roms/u-boot/drivers/spi/tegra114_spi.c new file mode 100644 index 000000000..f0256d8e6 --- /dev/null +++ b/roms/u-boot/drivers/spi/tegra114_spi.c @@ -0,0 +1,400 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * NVIDIA Tegra SPI controller (T114 and later) + * + * Copyright (c) 2010-2013 NVIDIA Corporation + */ + +#include <common.h> +#include <dm.h> +#include <log.h> +#include <time.h> +#include <asm/io.h> +#include <asm/arch/clock.h> +#include <asm/arch-tegra/clk_rst.h> +#include <spi.h> +#include <linux/bitops.h> +#include <linux/delay.h> +#include "tegra_spi.h" + +/* COMMAND1 */ +#define SPI_CMD1_GO BIT(31) +#define SPI_CMD1_M_S BIT(30) +#define SPI_CMD1_MODE_MASK GENMASK(1, 0) +#define SPI_CMD1_MODE_SHIFT 28 +#define SPI_CMD1_CS_SEL_MASK GENMASK(1, 0) +#define SPI_CMD1_CS_SEL_SHIFT 26 +#define SPI_CMD1_CS_POL_INACTIVE3 BIT(25) +#define SPI_CMD1_CS_POL_INACTIVE2 BIT(24) +#define SPI_CMD1_CS_POL_INACTIVE1 BIT(23) +#define SPI_CMD1_CS_POL_INACTIVE0 BIT(22) +#define SPI_CMD1_CS_SW_HW BIT(21) +#define SPI_CMD1_CS_SW_VAL BIT(20) +#define SPI_CMD1_IDLE_SDA_MASK GENMASK(1, 0) +#define SPI_CMD1_IDLE_SDA_SHIFT 18 +#define SPI_CMD1_BIDIR BIT(17) +#define SPI_CMD1_LSBI_FE BIT(16) +#define SPI_CMD1_LSBY_FE BIT(15) +#define SPI_CMD1_BOTH_EN_BIT BIT(14) +#define SPI_CMD1_BOTH_EN_BYTE BIT(13) +#define SPI_CMD1_RX_EN BIT(12) +#define SPI_CMD1_TX_EN BIT(11) +#define SPI_CMD1_PACKED BIT(5) +#define SPI_CMD1_BIT_LEN_MASK GENMASK(4, 0) +#define SPI_CMD1_BIT_LEN_SHIFT 0 + +/* COMMAND2 */ +#define SPI_CMD2_TX_CLK_TAP_DELAY BIT(6) +#define SPI_CMD2_TX_CLK_TAP_DELAY_MASK GENMASK(11, 6) +#define SPI_CMD2_RX_CLK_TAP_DELAY BIT(0) +#define SPI_CMD2_RX_CLK_TAP_DELAY_MASK GENMASK(5, 0) + +/* TRANSFER STATUS */ +#define SPI_XFER_STS_RDY BIT(30) + +/* FIFO STATUS */ +#define SPI_FIFO_STS_CS_INACTIVE BIT(31) +#define SPI_FIFO_STS_FRAME_END BIT(30) +#define SPI_FIFO_STS_RX_FIFO_FLUSH BIT(15) +#define SPI_FIFO_STS_TX_FIFO_FLUSH BIT(14) +#define SPI_FIFO_STS_ERR BIT(8) +#define SPI_FIFO_STS_TX_FIFO_OVF BIT(7) +#define SPI_FIFO_STS_TX_FIFO_UNR BIT(6) +#define SPI_FIFO_STS_RX_FIFO_OVF BIT(5) +#define SPI_FIFO_STS_RX_FIFO_UNR BIT(4) +#define SPI_FIFO_STS_TX_FIFO_FULL BIT(3) +#define SPI_FIFO_STS_TX_FIFO_EMPTY BIT(2) +#define SPI_FIFO_STS_RX_FIFO_FULL BIT(1) +#define SPI_FIFO_STS_RX_FIFO_EMPTY BIT(0) + +#define SPI_TIMEOUT 1000 +#define TEGRA_SPI_MAX_FREQ 52000000 + +struct spi_regs { + u32 command1; /* 000:SPI_COMMAND1 register */ + u32 command2; /* 004:SPI_COMMAND2 register */ + u32 timing1; /* 008:SPI_CS_TIM1 register */ + u32 timing2; /* 00c:SPI_CS_TIM2 register */ + u32 xfer_status;/* 010:SPI_TRANS_STATUS register */ + u32 fifo_status;/* 014:SPI_FIFO_STATUS register */ + u32 tx_data; /* 018:SPI_TX_DATA register */ + u32 rx_data; /* 01c:SPI_RX_DATA register */ + u32 dma_ctl; /* 020:SPI_DMA_CTL register */ + u32 dma_blk; /* 024:SPI_DMA_BLK register */ + u32 rsvd[56]; /* 028-107 reserved */ + u32 tx_fifo; /* 108:SPI_FIFO1 register */ + u32 rsvd2[31]; /* 10c-187 reserved */ + u32 rx_fifo; /* 188:SPI_FIFO2 register */ + u32 spare_ctl; /* 18c:SPI_SPARE_CTRL register */ +}; + +struct tegra114_spi_priv { + struct spi_regs *regs; + unsigned int freq; + unsigned int mode; + int periph_id; + int valid; + int last_transaction_us; +}; + +static int tegra114_spi_of_to_plat(struct udevice *bus) +{ + struct tegra_spi_plat *plat = dev_get_plat(bus); + + plat->base = dev_read_addr(bus); + plat->periph_id = clock_decode_periph_id(bus); + + 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 = dev_read_u32_default(bus, "spi-max-frequency", + 500000); + plat->deactivate_delay_us = dev_read_u32_default(bus, + "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 tegra114_spi_probe(struct udevice *bus) +{ + struct tegra_spi_plat *plat = dev_get_plat(bus); + struct tegra114_spi_priv *priv = dev_get_priv(bus); + struct spi_regs *regs; + ulong rate; + + priv->regs = (struct spi_regs *)plat->base; + regs = priv->regs; + + priv->last_transaction_us = timer_get_us(); + priv->freq = plat->frequency; + priv->periph_id = plat->periph_id; + + /* + * Change SPI clock to correct frequency, PLLP_OUT0 source, falling + * back to the oscillator if that is too fast. + */ + rate = clock_start_periph_pll(priv->periph_id, CLOCK_ID_PERIPH, + priv->freq); + if (rate > priv->freq + 100000) { + rate = clock_start_periph_pll(priv->periph_id, CLOCK_ID_OSC, + priv->freq); + if (rate != priv->freq) { + printf("Warning: SPI '%s' requested clock %u, actual clock %lu\n", + bus->name, priv->freq, rate); + } + } + udelay(plat->deactivate_delay_us); + + /* Clear stale status here */ + setbits_le32(®s->fifo_status, + SPI_FIFO_STS_ERR | + SPI_FIFO_STS_TX_FIFO_OVF | + SPI_FIFO_STS_TX_FIFO_UNR | + SPI_FIFO_STS_RX_FIFO_OVF | + SPI_FIFO_STS_RX_FIFO_UNR | + SPI_FIFO_STS_TX_FIFO_FULL | + SPI_FIFO_STS_TX_FIFO_EMPTY | + SPI_FIFO_STS_RX_FIFO_FULL | + SPI_FIFO_STS_RX_FIFO_EMPTY); + debug("%s: FIFO STATUS = %08x\n", __func__, readl(®s->fifo_status)); + + setbits_le32(&priv->regs->command1, SPI_CMD1_M_S | SPI_CMD1_CS_SW_HW | + (priv->mode << SPI_CMD1_MODE_SHIFT) | SPI_CMD1_CS_SW_VAL); + debug("%s: COMMAND1 = %08x\n", __func__, readl(®s->command1)); + + return 0; +} + +/** + * Activate the CS by driving it LOW + * + * @param slave Pointer to spi_slave to which controller has to + * communicate with + */ +static void spi_cs_activate(struct udevice *dev) +{ + struct udevice *bus = dev->parent; + struct tegra_spi_plat *pdata = dev_get_plat(bus); + struct tegra114_spi_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); + } + + clrbits_le32(&priv->regs->command1, SPI_CMD1_CS_SW_VAL); +} + +/** + * Deactivate the CS by driving it HIGH + * + * @param slave Pointer to spi_slave to which controller has to + * communicate with + */ +static void spi_cs_deactivate(struct udevice *dev) +{ + struct udevice *bus = dev->parent; + struct tegra_spi_plat *pdata = dev_get_plat(bus); + struct tegra114_spi_priv *priv = dev_get_priv(bus); + + setbits_le32(&priv->regs->command1, SPI_CMD1_CS_SW_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(); + + debug("Deactivate CS, bus '%s'\n", bus->name); +} + +static int tegra114_spi_xfer(struct udevice *dev, unsigned int bitlen, + const void *data_out, void *data_in, + unsigned long flags) +{ + struct udevice *bus = dev->parent; + struct tegra114_spi_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__, dev_seq(bus), spi_chip_select(dev), dout, din, bitlen); + if (bitlen % 8) + return -1; + num_bytes = bitlen / 8; + + ret = 0; + + if (flags & SPI_XFER_BEGIN) + spi_cs_activate(dev); + + /* clear all error status bits */ + reg = readl(®s->fifo_status); + writel(reg, ®s->fifo_status); + + clrsetbits_le32(®s->command1, SPI_CMD1_CS_SW_VAL, + SPI_CMD1_RX_EN | SPI_CMD1_TX_EN | SPI_CMD1_LSBY_FE | + (spi_chip_select(dev) << SPI_CMD1_CS_SEL_SHIFT)); + + /* set xfer size to 1 block (32 bits) */ + writel(0, ®s->dma_blk); + + /* handle data in 32-bit chunks */ + while (num_bytes > 0) { + int bytes; + 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]; + dout += bytes; + } + + num_bytes -= bytes; + + /* clear ready bit */ + setbits_le32(®s->xfer_status, SPI_XFER_STS_RDY); + + clrsetbits_le32(®s->command1, + SPI_CMD1_BIT_LEN_MASK << SPI_CMD1_BIT_LEN_SHIFT, + (bytes * 8 - 1) << SPI_CMD1_BIT_LEN_SHIFT); + writel(tmpdout, ®s->tx_fifo); + setbits_le32(®s->command1, SPI_CMD1_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; tm < SPI_TIMEOUT; ++tm) { + u32 fifo_status, xfer_status; + + xfer_status = readl(®s->xfer_status); + if (!(xfer_status & SPI_XFER_STS_RDY)) + continue; + + fifo_status = readl(®s->fifo_status); + if (fifo_status & SPI_FIFO_STS_ERR) { + debug("%s: got a fifo error: ", __func__); + if (fifo_status & SPI_FIFO_STS_TX_FIFO_OVF) + debug("tx FIFO overflow "); + if (fifo_status & SPI_FIFO_STS_TX_FIFO_UNR) + debug("tx FIFO underrun "); + if (fifo_status & SPI_FIFO_STS_RX_FIFO_OVF) + debug("rx FIFO overflow "); + if (fifo_status & SPI_FIFO_STS_RX_FIFO_UNR) + debug("rx FIFO underrun "); + if (fifo_status & SPI_FIFO_STS_TX_FIFO_FULL) + debug("tx FIFO full "); + if (fifo_status & SPI_FIFO_STS_TX_FIFO_EMPTY) + debug("tx FIFO empty "); + if (fifo_status & SPI_FIFO_STS_RX_FIFO_FULL) + debug("rx FIFO full "); + if (fifo_status & SPI_FIFO_STS_RX_FIFO_EMPTY) + debug("rx FIFO empty "); + debug("\n"); + break; + } + + if (!(fifo_status & SPI_FIFO_STS_RX_FIFO_EMPTY)) { + tmpdin = readl(®s->rx_fifo); + + /* swap bytes read in */ + if (din != NULL) { + for (i = bytes - 1; i >= 0; --i) { + din[i] = tmpdin & 0xff; + tmpdin >>= 8; + } + din += bytes; + } + + /* We can exit when we've had both RX and TX */ + break; + } + } + + if (tm >= SPI_TIMEOUT) + ret = tm; + + /* clear ACK RDY, etc. bits */ + writel(readl(®s->fifo_status), ®s->fifo_status); + } + + if (flags & SPI_XFER_END) + spi_cs_deactivate(dev); + + debug("%s: transfer ended. Value=%08x, fifo_status = %08x\n", + __func__, tmpdin, readl(®s->fifo_status)); + + if (ret) { + printf("%s: timeout during SPI transfer, tm %d\n", + __func__, ret); + return -1; + } + + return ret; +} + +static int tegra114_spi_set_speed(struct udevice *bus, uint speed) +{ + struct tegra_spi_plat *plat = dev_get_plat(bus); + struct tegra114_spi_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 tegra114_spi_set_mode(struct udevice *bus, uint mode) +{ + struct tegra114_spi_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 tegra114_spi_ops = { + .xfer = tegra114_spi_xfer, + .set_speed = tegra114_spi_set_speed, + .set_mode = tegra114_spi_set_mode, + /* + * cs_info is not needed, since we require all chip selects to be + * in the device tree explicitly + */ +}; + +static const struct udevice_id tegra114_spi_ids[] = { + { .compatible = "nvidia,tegra114-spi" }, + { } +}; + +U_BOOT_DRIVER(tegra114_spi) = { + .name = "tegra114_spi", + .id = UCLASS_SPI, + .of_match = tegra114_spi_ids, + .ops = &tegra114_spi_ops, + .of_to_plat = tegra114_spi_of_to_plat, + .plat_auto = sizeof(struct tegra_spi_plat), + .priv_auto = sizeof(struct tegra114_spi_priv), + .probe = tegra114_spi_probe, +}; |