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u-boot/drivers/spi/tegra114_spi.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style 
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

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// 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 <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch-tegra/clk_rst.h>
#include <spi.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_ofdata_to_platdata(struct udevice *bus)
{
struct tegra_spi_platdata *plat = bus->platdata;
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_platdata *plat = dev_get_platdata(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(&regs->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(&regs->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(&regs->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_platdata *pdata = dev_get_platdata(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_platdata *pdata = dev_get_platdata(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__, bus->seq, 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(&regs->fifo_status);
writel(reg, &regs->fifo_status);
clrsetbits_le32(&regs->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, &regs->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(&regs->xfer_status, SPI_XFER_STS_RDY);
clrsetbits_le32(&regs->command1,
SPI_CMD1_BIT_LEN_MASK << SPI_CMD1_BIT_LEN_SHIFT,
(bytes * 8 - 1) << SPI_CMD1_BIT_LEN_SHIFT);
writel(tmpdout, &regs->tx_fifo);
setbits_le32(&regs->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(&regs->xfer_status);
if (!(xfer_status & SPI_XFER_STS_RDY))
continue;
fifo_status = readl(&regs->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(&regs->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(&regs->fifo_status), &regs->fifo_status);
}
if (flags & SPI_XFER_END)
spi_cs_deactivate(dev);
debug("%s: transfer ended. Value=%08x, fifo_status = %08x\n",
__func__, tmpdin, readl(&regs->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_platdata *plat = bus->platdata;
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,
.ofdata_to_platdata = tegra114_spi_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct tegra_spi_platdata),
.priv_auto_alloc_size = sizeof(struct tegra114_spi_priv),
.probe = tegra114_spi_probe,
};
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