// SPDX-License-Identifier: GPL-2.0+
//
// Copyright 2013 Freescale Semiconductor, Inc.
// Copyright 2020 NXP
//
// Freescale DSPI driver
// This file contains a driver for the Freescale DSPI
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi-fsl-dspi.h>
#define DRIVER_NAME "fsl-dspi"
#define SPI_MCR 0x00
#define SPI_MCR_HOST BIT(31)
#define SPI_MCR_PCSIS(x) ((x) << 16)
#define SPI_MCR_CLR_TXF BIT(11)
#define SPI_MCR_CLR_RXF BIT(10)
#define SPI_MCR_XSPI BIT(3)
#define SPI_MCR_DIS_TXF BIT(13)
#define SPI_MCR_DIS_RXF BIT(12)
#define SPI_MCR_HALT BIT(0)
#define SPI_TCR 0x08
#define SPI_TCR_GET_TCNT(x) (((x) & GENMASK(31, 16)) >> 16)
#define SPI_CTAR(x) (0x0c + (((x) & GENMASK(1, 0)) * 4))
#define SPI_CTAR_FMSZ(x) (((x) << 27) & GENMASK(30, 27))
#define SPI_CTAR_CPOL BIT(26)
#define SPI_CTAR_CPHA BIT(25)
#define SPI_CTAR_LSBFE BIT(24)
#define SPI_CTAR_PCSSCK(x) (((x) << 22) & GENMASK(23, 22))
#define SPI_CTAR_PASC(x) (((x) << 20) & GENMASK(21, 20))
#define SPI_CTAR_PDT(x) (((x) << 18) & GENMASK(19, 18))
#define SPI_CTAR_PBR(x) (((x) << 16) & GENMASK(17, 16))
#define SPI_CTAR_CSSCK(x) (((x) << 12) & GENMASK(15, 12))
#define SPI_CTAR_ASC(x) (((x) << 8) & GENMASK(11, 8))
#define SPI_CTAR_DT(x) (((x) << 4) & GENMASK(7, 4))
#define SPI_CTAR_BR(x) ((x) & GENMASK(3, 0))
#define SPI_CTAR_SCALE_BITS 0xf
#define SPI_CTAR0_SLAVE 0x0c
#define SPI_SR 0x2c
#define SPI_SR_TCFQF BIT(31)
#define SPI_SR_TFUF BIT(27)
#define SPI_SR_TFFF BIT(25)
#define SPI_SR_CMDTCF BIT(23)
#define SPI_SR_SPEF BIT(21)
#define SPI_SR_RFOF BIT(19)
#define SPI_SR_TFIWF BIT(18)
#define SPI_SR_RFDF BIT(17)
#define SPI_SR_CMDFFF BIT(16)
#define SPI_SR_CLEAR (SPI_SR_TCFQF | \
SPI_SR_TFUF | SPI_SR_TFFF | \
SPI_SR_CMDTCF | SPI_SR_SPEF | \
SPI_SR_RFOF | SPI_SR_TFIWF | \
SPI_SR_RFDF | SPI_SR_CMDFFF)
#define SPI_RSER_TFFFE BIT(25)
#define SPI_RSER_TFFFD BIT(24)
#define SPI_RSER_RFDFE BIT(17)
#define SPI_RSER_RFDFD BIT(16)
#define SPI_RSER 0x30
#define SPI_RSER_TCFQE BIT(31)
#define SPI_RSER_CMDTCFE BIT(23)
#define SPI_PUSHR 0x34
#define SPI_PUSHR_CMD_CONT BIT(15)
#define SPI_PUSHR_CMD_CTAS(x) (((x) << 12 & GENMASK(14, 12)))
#define SPI_PUSHR_CMD_EOQ BIT(11)
#define SPI_PUSHR_CMD_CTCNT BIT(10)
#define SPI_PUSHR_CMD_PCS(x) (BIT(x) & GENMASK(5, 0))
#define SPI_PUSHR_SLAVE 0x34
#define SPI_POPR 0x38
#define SPI_TXFR0 0x3c
#define SPI_TXFR1 0x40
#define SPI_TXFR2 0x44
#define SPI_TXFR3 0x48
#define SPI_RXFR0 0x7c
#define SPI_RXFR1 0x80
#define SPI_RXFR2 0x84
#define SPI_RXFR3 0x88
#define SPI_CTARE(x) (0x11c + (((x) & GENMASK(1, 0)) * 4))
#define SPI_CTARE_FMSZE(x) (((x) & 0x1) << 16)
#define SPI_CTARE_DTCP(x) ((x) & 0x7ff)
#define SPI_SREX 0x13c
#define SPI_FRAME_BITS(bits) SPI_CTAR_FMSZ((bits) - 1)
#define SPI_FRAME_EBITS(bits) SPI_CTARE_FMSZE(((bits) - 1) >> 4)
#define DMA_COMPLETION_TIMEOUT msecs_to_jiffies(3000)
struct chip_data {
u32 ctar_val;
};
enum dspi_trans_mode {
DSPI_XSPI_MODE,
DSPI_DMA_MODE,
};
struct fsl_dspi_devtype_data {
enum dspi_trans_mode trans_mode;
u8 max_clock_factor;
int fifo_size;
};
enum {
LS1021A,
LS1012A,
LS1028A,
LS1043A,
LS1046A,
LS2080A,
LS2085A,
LX2160A,
MCF5441X,
VF610,
};
static const struct fsl_dspi_devtype_data devtype_data[] = {
[VF610] = {
.trans_mode = DSPI_DMA_MODE,
.max_clock_factor = 2,
.fifo_size = 4,
},
[LS1021A] = {
/* Has A-011218 DMA erratum */
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 4,
},
[LS1012A] = {
/* Has A-011218 DMA erratum */
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 16,
},
[LS1028A] = {
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 4,
},
[LS1043A] = {
/* Has A-011218 DMA erratum */
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 16,
},
[LS1046A] = {
/* Has A-011218 DMA erratum */
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 16,
},
[LS2080A] = {
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 4,
},
[LS2085A] = {
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 4,
},
[LX2160A] = {
.trans_mode = DSPI_XSPI_MODE,
.max_clock_factor = 8,
.fifo_size = 4,
},
[MCF5441X] = {
.trans_mode = DSPI_DMA_MODE,
.max_clock_factor = 8,
.fifo_size = 16,
},
};
struct fsl_dspi_dma {
u32 *tx_dma_buf;
struct dma_chan *chan_tx;
dma_addr_t tx_dma_phys;
struct completion cmd_tx_complete;
struct dma_async_tx_descriptor *tx_desc;
u32 *rx_dma_buf;
struct dma_chan *chan_rx;
dma_addr_t rx_dma_phys;
struct completion cmd_rx_complete;
struct dma_async_tx_descriptor *rx_desc;
};
struct fsl_dspi {
struct spi_controller *ctlr;
struct platform_device *pdev;
struct regmap *regmap;
struct regmap *regmap_pushr;
int irq;
struct clk *clk;
struct spi_transfer *cur_transfer;
struct spi_message *cur_msg;
struct chip_data *cur_chip;
size_t progress;
size_t len;
const void *tx;
void *rx;
u16 tx_cmd;
const struct fsl_dspi_devtype_data *devtype_data;
struct completion xfer_done;
struct fsl_dspi_dma *dma;
int oper_word_size;
int oper_bits_per_word;
int words_in_flight;
/*
* Offsets for CMD and TXDATA within SPI_PUSHR when accessed
* individually (in XSPI mode)
*/
int pushr_cmd;
int pushr_tx;
void (*host_to_dev)(struct fsl_dspi *dspi, u32 *txdata);
void (*dev_to_host)(struct fsl_dspi *dspi, u32 rxdata);
};
static void dspi_native_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
{
switch (dspi->oper_word_size) {
case 1:
*txdata = *(u8 *)dspi->tx;
break;
case 2:
*txdata = *(u16 *)dspi->tx;
break;
case 4:
*txdata = *(u32 *)dspi->tx;
break;
}
dspi->tx += dspi->oper_word_size;
}
static void dspi_native_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
{
switch (dspi->oper_word_size) {
case 1:
*(u8 *)dspi->rx = rxdata;
break;
case 2:
*(u16 *)dspi->rx = rxdata;
break;
case 4:
*(u32 *)dspi->rx = rxdata;
break;
}
dspi->rx += dspi->oper_word_size;
}
static void dspi_8on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
{
*txdata = cpu_to_be32(*(u32 *)dspi->tx);
dspi->tx += sizeof(u32);
}
static void dspi_8on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
{
*(u32 *)dspi->rx = be32_to_cpu(rxdata);
dspi->rx += sizeof(u32);
}
static void dspi_8on16_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
{
*txdata = cpu_to_be16(*(u16 *)dspi->tx);
dspi->tx += sizeof(u16);
}
static void dspi_8on16_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
{
*(u16 *)dspi->rx = be16_to_cpu(rxdata);
dspi->rx += sizeof(u16);
}
static void dspi_16on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
{
u16 hi = *(u16 *)dspi->tx;
u16 lo = *(u16 *)(dspi->tx + 2);
*txdata = (u32)hi << 16 | lo;
dspi->tx += sizeof(u32);
}
static void dspi_16on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
{
u16 hi = rxdata & 0xffff;
u16 lo = rxdata >> 16;
*(u16 *)dspi->rx = lo;
*(u16 *)(dspi->rx + 2) = hi;
dspi->rx += sizeof(u32);
}
/*
* Pop one word from the TX buffer for pushing into the
* PUSHR register (TX FIFO)
*/
static u32 dspi_pop_tx(struct fsl_dspi *dspi)
{
u32 txdata = 0;
if (dspi->tx)
dspi->host_to_dev(dspi, &txdata);
dspi->len -= dspi->oper_word_size;
return txdata;
}
/* Prepare one TX FIFO entry (txdata plus cmd) */
static u32 dspi_pop_tx_pushr(struct fsl_dspi *dspi)
{
u16 cmd = dspi->tx_cmd, data = dspi_pop_tx(dspi);
if (spi_controller_is_target(dspi->ctlr))
return data;
if (dspi->len > 0)
cmd |= SPI_PUSHR_CMD_CONT;
return cmd << 16 | data;
}
/* Push one word to the RX buffer from the POPR register (RX FIFO) */
static void dspi_push_rx(struct fsl_dspi *dspi, u32 rxdata)
{
if (!dspi->rx)
return;
dspi->dev_to_host(dspi, rxdata);
}
static void dspi_tx_dma_callback(void *arg)
{
struct fsl_dspi *dspi = arg;
struct fsl_dspi_dma *dma = dspi->dma;
complete(&dma->cmd_tx_complete);
}
static void dspi_rx_dma_callback(void *arg)
{
struct fsl_dspi *dspi = arg;
struct fsl_dspi_dma *dma = dspi->dma;
int i;
if (dspi->rx) {
for (i = 0; i < dspi->words_in_flight; i++)
dspi_push_rx(dspi, dspi->dma->rx_dma_buf[i]);
}
complete(&dma->cmd_rx_complete);
}
static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
{
struct device *dev = &dspi->pdev->dev;
struct fsl_dspi_dma *dma = dspi->dma;
int time_left;
int i;
for (i = 0; i < dspi->words_in_flight; i++)
dspi->dma->tx_dma_buf[i] = dspi_pop_tx_pushr(dspi);
dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
dma->tx_dma_phys,
dspi->words_in_flight *
DMA_SLAVE_BUSWIDTH_4_BYTES,
DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!dma->tx_desc) {
dev_err(dev, "Not able to get desc for DMA xfer\n");
return -EIO;
}
dma->tx_desc->callback = dspi_tx_dma_callback;
dma->tx_desc->callback_param = dspi;
if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
dev_err(dev, "DMA submit failed\n");
return -EINVAL;
}
dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
dma->rx_dma_phys,
dspi->words_in_flight *
DMA_SLAVE_BUSWIDTH_4_BYTES,
DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!dma->rx_desc) {
dev_err(dev, "Not able to get desc for DMA xfer\n");
return -EIO;
}
dma->rx_desc->callback = dspi_rx_dma_callback;
dma->rx_desc->callback_param = dspi;
if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
dev_err(dev, "DMA submit failed\n");
return -EINVAL;
}
reinit_completion(&dspi->dma->cmd_rx_complete);
reinit_completion(&dspi->dma->cmd_tx_complete);
dma_async_issue_pending(dma->chan_rx);
dma_async_issue_pending(dma->chan_tx);
if (spi_controller_is_target(dspi->ctlr)) {
wait_for_completion_interruptible(&dspi->dma->cmd_rx_complete);
return 0;
}
time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
DMA_COMPLETION_TIMEOUT);
if (time_left == 0) {
dev_err(dev, "DMA tx timeout\n");
dmaengine_terminate_all(dma->chan_tx);
dmaengine_terminate_all(dma->chan_rx);
return -ETIMEDOUT;
}
time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
DMA_COMPLETION_TIMEOUT);
if (time_left == 0) {
dev_err(dev, "DMA rx timeout\n");
dmaengine_terminate_all(dma->chan_tx);
dmaengine_terminate_all(dma->chan_rx);
return -ETIMEDOUT;
}
return 0;
}
static void dspi_setup_accel(struct fsl_dspi *dspi);
static int dspi_dma_xfer(struct fsl_dspi *dspi)
{
struct spi_message *message = dspi->cur_msg;
struct device *dev = &dspi->pdev->dev;
int ret = 0;
/*
* dspi->len gets decremented by dspi_pop_tx_pushr in
* dspi_next_xfer_dma_submit
*/
while (dspi->len) {
/* Figure out operational bits-per-word for this chunk */
dspi_setup_accel(dspi);
dspi->words_in_flight = dspi->len / dspi->oper_word_size;
if (dspi->words_in_flight > dspi->devtype_data->fifo_size)
dspi->words_in_flight = dspi->devtype_data->fifo_size;
message->actual_length += dspi->words_in_flight *
dspi->oper_word_size;
ret = dspi_next_xfer_dma_submit(dspi);
if (ret) {
dev_err(dev, "DMA transfer failed\n");
break;
}
}
return ret;
}
static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
{
int dma_bufsize = dspi->devtype_data->fifo_size * 2;
struct device *dev = &dspi->pdev->dev;
struct dma_slave_config cfg;
struct fsl_dspi_dma *dma;
int ret;
dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
if (!dma)
return -ENOMEM;
dma->chan_rx = dma_request_chan(dev, "rx");
if (IS_ERR(dma->chan_rx))
return dev_err_probe(dev, PTR_ERR(dma->chan_rx), "rx dma channel not available\n");
dma->chan_tx = dma_request_chan(dev, "tx");
if (IS_ERR(dma->chan_tx)) {
ret = dev_err_probe(dev, PTR_ERR(dma->chan_tx), "tx dma channel not available\n");
goto err_tx_channel;
}
dma->tx_dma_buf = dma_alloc_coherent(dma->chan_tx->device->dev,
dma_bufsize, &dma->tx_dma_phys,
GFP_KERNEL);
if (!dma->tx_dma_buf) {
ret = -ENOMEM;
goto err_tx_dma_buf;
}
dma->rx_dma_buf = dma_alloc_coherent(dma->chan_rx->device->dev,
dma_bufsize, &dma->rx_dma_phys,
GFP_KERNEL);
if (!dma->rx_dma_buf) {
ret = -ENOMEM;
goto err_rx_dma_buf;
}
memset(&cfg, 0, sizeof(cfg));
cfg.src_addr = phy_addr + SPI_POPR;
cfg.dst_addr = phy_addr + SPI_PUSHR;
cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
cfg.src_maxburst = 1;
cfg.dst_maxburst = 1;
cfg.direction = DMA_DEV_TO_MEM;
ret = dmaengine_slave_config(dma->chan_rx, &cfg);
if (ret) {
dev_err_probe(dev, ret, "can't configure rx dma channel\n");
goto err_slave_config;
}
cfg.direction = DMA_MEM_TO_DEV;
ret = dmaengine_slave_config(dma->chan_tx, &cfg);
if (ret) {
dev_err_probe(dev, ret, "can't configure tx dma channel\n");
goto err_slave_config;
}
dspi->dma = dma;
init_completion(&dma->cmd_tx_complete);
init_completion(&dma->cmd_rx_complete);
return 0;
err_slave_config:
dma_free_coherent(dma->chan_rx->device->dev,
dma_bufsize, dma->rx_dma_buf, dma->rx_dma_phys);
err_rx_dma_buf:
dma_free_coherent(dma->chan_tx->device->dev,
dma_bufsize, dma->tx_dma_buf, dma->tx_dma_phys);
err_tx_dma_buf:
dma_release_channel(dma->chan_tx);
err_tx_channel:
dma_release_channel(dma->chan_rx);
devm_kfree(dev, dma);
dspi->dma = NULL;
return ret;
}
static void dspi_release_dma(struct fsl_dspi *dspi)
{
int dma_bufsize = dspi->devtype_data->fifo_size * 2;
struct fsl_dspi_dma *dma = dspi->dma;
if (!dma)
return;
if (dma->chan_tx) {
dma_free_coherent(dma->chan_tx->device->dev, dma_bufsize,
dma->tx_dma_buf, dma->tx_dma_phys);
dma_release_channel(dma->chan_tx);
}
if (dma->chan_rx) {
dma_free_coherent(dma->chan_rx->device->dev, dma_bufsize,
dma->rx_dma_buf, dma->rx_dma_phys);
dma_release_channel(dma->chan_rx);
}
}
static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
unsigned long clkrate)
{
/* Valid baud rate pre-scaler values */
int pbr_tbl[4] = {2, 3, 5, 7};
int brs[16] = { 2, 4, 6, 8,
16, 32, 64, 128,
256, 512, 1024, 2048,
4096, 8192, 16384, 32768 };
int scale_needed, scale, minscale = INT_MAX;
int i, j;
scale_needed = clkrate / speed_hz;
if (clkrate % speed_hz)
scale_needed++;
for (i = 0; i < ARRAY_SIZE(brs); i++)
for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
scale = brs[i] * pbr_tbl[j];
if (scale >= scale_needed) {
if (scale < minscale) {
minscale = scale;
*br = i;
*pbr = j;
}
break;
}
}
if (minscale == INT_MAX) {
pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
speed_hz, clkrate);
*pbr = ARRAY_SIZE(pbr_tbl) - 1;
*br = ARRAY_SIZE(brs) - 1;
}
}
static void ns_delay_scale(char *psc, char *sc, int delay_ns,
unsigned long clkrate)
{
int scale_needed, scale, minscale = INT_MAX;
int pscale_tbl[4] = {1, 3, 5, 7};
u32 remainder;
int i, j;
scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
&remainder);
if (remainder)
scale_needed++;
for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
scale = pscale_tbl[i] * (2 << j);
if (scale >= scale_needed) {
if (scale < minscale) {
minscale = scale;
*psc = i;
*sc = j;
}
break;
}
}
if (minscale == INT_MAX) {
pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
delay_ns, clkrate);
*psc = ARRAY_SIZE(pscale_tbl) - 1;
*sc = SPI_CTAR_SCALE_BITS;
}
}
static void dspi_pushr_cmd_write(struct fsl_dspi *dspi, u16 cmd)
{
/*
* The only time when the PCS doesn't need continuation after this word
* is when it's last. We need to look ahead, because we actually call
* dspi_pop_tx (the function that decrements dspi->len) _after_
* dspi_pushr_cmd_write with XSPI mode. As for how much in advance? One
* word is enough. If there's more to transmit than that,
* dspi_xspi_write will know to split the FIFO writes in 2, and
* generate a new PUSHR command with the final word that will have PCS
* deasserted (not continued) here.
*/
if (dspi->len > dspi->oper_word_size)
cmd |= SPI_PUSHR_CMD_CONT;
regmap_write(dspi->regmap_pushr, dspi->pushr_cmd, cmd);
}
static void dspi_pushr_txdata_write(struct fsl_dspi *dspi, u16 txdata)
{
regmap_write(dspi->regmap_pushr, dspi->pushr_tx, txdata);
}
static void dspi_xspi_fifo_write(struct fsl_dspi *dspi, int num_words)
{
int num_bytes = num_words * dspi->oper_word_size;
u16 tx_cmd = dspi->tx_cmd;
/*
* If the PCS needs to de-assert (i.e. we're at the end of the buffer
* and cs_change does not want the PCS to stay on), then we need a new
* PUSHR command, since this one (for the body of the buffer)
* necessarily has the CONT bit set.
* So send one word less during this go, to force a split and a command
* with a single word next time, when CONT will be unset.
*/
if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT) && num_bytes == dspi->len)
tx_cmd |= SPI_PUSHR_CMD_EOQ;
/* Update CTARE */
regmap_write(dspi->regmap, SPI_CTARE(0),
SPI_FRAME_EBITS(dspi->oper_bits_per_word) |
SPI_CTARE_DTCP(num_words));
/*
* Write the CMD FIFO entry first, and then the two
* corresponding TX FIFO entries (or one...).
*/
dspi_pushr_cmd_write(dspi, tx_cmd);
/* Fill TX FIFO with as many transfers as possible */
while (num_words--) {
u32 data = dspi_pop_tx(dspi);
dspi_pushr_txdata_write(dspi, data & 0xFFFF);
if (dspi->oper_bits_per_word > 16)
dspi_pushr_txdata_write(dspi, data >> 16);
}
}
static u32 dspi_popr_read(struct fsl_dspi *dspi)
{
u32 rxdata = 0;
regmap_read(dspi->regmap, SPI_POPR, &rxdata);
return rxdata;
}
static void dspi_fifo_read(struct fsl_dspi *dspi)
{
int num_fifo_entries = dspi->words_in_flight;
/* Read one FIFO entry and push to rx buffer */
while (num_fifo_entries--)
dspi_push_rx(dspi, dspi_popr_read(dspi));
}
static void dspi_setup_accel(struct fsl_dspi *dspi)
{
struct spi_transfer *xfer = dspi->cur_transfer;
bool odd = !!(dspi->len & 1);
/* No accel for frames not multiple of 8 bits at the moment */
if (xfer->bits_per_word % 8)
goto no_accel;
if (!odd && dspi->len <= dspi->devtype_data->fifo_size * 2) {
dspi->oper_bits_per_word = 16;
} else if (odd && dspi->len <= dspi->devtype_data->fifo_size) {
dspi->oper_bits_per_word = 8;
} else {
/* Start off with maximum supported by hardware */
if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
dspi->oper_bits_per_word = 32;
else
dspi->oper_bits_per_word = 16;
/*
* And go down only if the buffer can't be sent with
* words this big
*/
do {
if (dspi->len >= DIV_ROUND_UP(dspi->oper_bits_per_word, 8))
break;
dspi->oper_bits_per_word /= 2;
} while (dspi->oper_bits_per_word > 8);
}
if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 32) {
dspi->dev_to_host = dspi_8on32_dev_to_host;
dspi->host_to_dev = dspi_8on32_host_to_dev;
} else if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 16) {
dspi->dev_to_host = dspi_8on16_dev_to_host;
dspi->host_to_dev = dspi_8on16_host_to_dev;
} else if (xfer->bits_per_word == 16 && dspi->oper_bits_per_word == 32) {
dspi->dev_to_host = dspi_16on32_dev_to_host;
dspi->host_to_dev = dspi_16on32_host_to_dev;
} else {
no_accel:
dspi->dev_to_host = dspi_native_dev_to_host;
dspi->host_to_dev = dspi_native_host_to_dev;
dspi->oper_bits_per_word = xfer->bits_per_word;
}
dspi->oper_word_size = DIV_ROUND_UP(dspi->oper_bits_per_word, 8);
/*
* Update CTAR here (code is common for XSPI and DMA modes).
* We will update CTARE in the portion specific to XSPI, when we
* also know the preload value (DTCP).
*/
regmap_write(dspi->regmap, SPI_CTAR(0),
dspi->cur_chip->ctar_val |
SPI_FRAME_BITS(dspi->oper_bits_per_word));
}
static void dspi_fifo_write(struct fsl_dspi *dspi)
{
int num_fifo_entries = dspi->devtype_data->fifo_size;
struct spi_transfer *xfer = dspi->cur_transfer;
struct spi_message *msg = dspi->cur_msg;
int num_words, num_bytes;
dspi_setup_accel(dspi);
/* In XSPI mode each 32-bit word occupies 2 TX FIFO entries */
if (dspi->oper_word_size == 4)
num_fifo_entries /= 2;
/*
* Integer division intentionally trims off odd (or non-multiple of 4)
* numbers of bytes at the end of the buffer, which will be sent next
* time using a smaller oper_word_size.
*/
num_words = dspi->len / dspi->oper_word_size;
if (num_words > num_fifo_entries)
num_words = num_fifo_entries;
/* Update total number of bytes that were transferred */
num_bytes = num_words * dspi->oper_word_size;
msg->actual_length += num_bytes;
dspi->progress += num_bytes / DIV_ROUND_UP(xfer->bits_per_word, 8);
/*
* Update shared variable for use in the next interrupt (both in
* dspi_fifo_read and in dspi_fifo_write).
*/
dspi->words_in_flight = num_words;
spi_take_timestamp_pre(dspi->ctlr, xfer, dspi->progress, !dspi->irq);
dspi_xspi_fifo_write(dspi, num_words);
/*
* Everything after this point is in a potential race with the next
* interrupt, so we must never use dspi->words_in_flight again since it
* might already be modified by the next dspi_fifo_write.
*/
spi_take_timestamp_post(dspi->ctlr, dspi->cur_transfer,
dspi->progress, !dspi->irq);
}
static int dspi_rxtx(struct fsl_dspi *dspi)
{
dspi_fifo_read(dspi);
if (!dspi->len)
/* Success! */
return 0;
dspi_fifo_write(dspi);
return -EINPROGRESS;
}
static int dspi_poll(struct fsl_dspi *dspi)
{
int tries = 1000;
u32 spi_sr;
do {
regmap_read(dspi->regmap, SPI_SR, &spi_sr);
regmap_write(dspi->regmap, SPI_SR, spi_sr);
if (spi_sr & SPI_SR_CMDTCF)
break;
} while (--tries);
if (!tries)
return -ETIMEDOUT;
return dspi_rxtx(dspi);
}
static irqreturn_t dspi_interrupt(int irq, void *dev_id)
{
struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
u32 spi_sr;
regmap_read(dspi->regmap, SPI_SR, &spi_sr);
regmap_write(dspi->regmap, SPI_SR, spi_sr);
if (!(spi_sr & SPI_SR_CMDTCF))
return IRQ_NONE;
if (dspi_rxtx(dspi) == 0)
complete(&dspi->xfer_done);
return IRQ_HANDLED;
}
static void dspi_assert_cs(struct spi_device *spi, bool *cs)
{
if (!spi_get_csgpiod(spi, 0) || *cs)
return;
gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), true);
*cs = true;
}
static void dspi_deassert_cs(struct spi_device *spi, bool *cs)
{
if (!spi_get_csgpiod(spi, 0) || !*cs)
return;
gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), false);
*cs = false;
}
static int dspi_transfer_one_message(struct spi_controller *ctlr,
struct spi_message *message)
{
struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
struct spi_device *spi = message->spi;
struct spi_transfer *transfer;
bool cs = false;
int status = 0;
message->actual_length = 0;
list_for_each_entry(transfer, &message->transfers, transfer_list) {
dspi->cur_transfer = transfer;
dspi->cur_msg = message;
dspi->cur_chip = spi_get_ctldata(spi);
dspi_assert_cs(spi, &cs);
/* Prepare command word for CMD FIFO */
dspi->tx_cmd = SPI_PUSHR_CMD_CTAS(0);
if (!spi_get_csgpiod(spi, 0))
dspi->tx_cmd |= SPI_PUSHR_CMD_PCS(spi_get_chipselect(spi, 0));
if (list_is_last(&dspi->cur_transfer->transfer_list,
&dspi->cur_msg->transfers)) {
/* Leave PCS activated after last transfer when
* cs_change is set.
*/
if (transfer->cs_change)
dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
} else {
/* Keep PCS active between transfers in same message
* when cs_change is not set, and de-activate PCS
* between transfers in the same message when
* cs_change is set.
*/
if (!transfer->cs_change)
dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
}
dspi->tx = transfer->tx_buf;
dspi->rx = transfer->rx_buf;
dspi->len = transfer->len;
dspi->progress = 0;
regmap_update_bits(dspi->regmap, SPI_MCR,
SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
spi_take_timestamp_pre(dspi->ctlr, dspi->cur_transfer,
dspi->progress, !dspi->irq);
if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
status = dspi_dma_xfer(dspi);
} else {
dspi_fifo_write(dspi);
if (dspi->irq) {
wait_for_completion(&dspi->xfer_done);
reinit_completion(&dspi->xfer_done);
} else {
do {
status = dspi_poll(dspi);
} while (status == -EINPROGRESS);
}
}
if (status)
break;
spi_transfer_delay_exec(transfer);
if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT))
dspi_deassert_cs(spi, &cs);
}
message->status = status;
spi_finalize_current_message(ctlr);
return status;
}
static int dspi_setup(struct spi_device *spi)
{
struct fsl_dspi *dspi = spi_controller_get_devdata(spi->controller);
u32 period_ns = DIV_ROUND_UP(NSEC_PER_SEC, spi->max_speed_hz);
unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
u32 quarter_period_ns = DIV_ROUND_UP(period_ns, 4);
u32 cs_sck_delay = 0, sck_cs_delay = 0;
struct fsl_dspi_platform_data *pdata;
unsigned char pasc = 0, asc = 0;
struct chip_data *chip;
unsigned long clkrate;
bool cs = true;
int val;
/* Only alloc on first setup */
chip = spi_get_ctldata(spi);
if (chip == NULL) {
chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
if (!chip)
return -ENOMEM;
}
pdata = dev_get_platdata(&dspi->pdev->dev);
if (!pdata) {
val = spi_delay_to_ns(&spi->cs_setup, NULL);
cs_sck_delay = val >= 0 ? val : 0;
if (!cs_sck_delay)
of_property_read_u32(spi->dev.of_node,
"fsl,spi-cs-sck-delay",
&cs_sck_delay);
val = spi_delay_to_ns(&spi->cs_hold, NULL);
sck_cs_delay = val >= 0 ? val : 0;
if (!sck_cs_delay)
of_property_read_u32(spi->dev.of_node,
"fsl,spi-sck-cs-delay",
&sck_cs_delay);
} else {
cs_sck_delay = pdata->cs_sck_delay;
sck_cs_delay = pdata->sck_cs_delay;
}
/* Since tCSC and tASC apply to continuous transfers too, avoid SCK
* glitches of half a cycle by never allowing tCSC + tASC to go below
* half a SCK period.
*/
if (cs_sck_delay < quarter_period_ns)
cs_sck_delay = quarter_period_ns;
if (sck_cs_delay < quarter_period_ns)
sck_cs_delay = quarter_period_ns;
dev_dbg(&spi->dev,
"DSPI controller timing params: CS-to-SCK delay %u ns, SCK-to-CS delay %u ns\n",
cs_sck_delay, sck_cs_delay);
clkrate = clk_get_rate(dspi->clk);
hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate);
/* Set PCS to SCK delay scale values */
ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
/* Set After SCK delay scale values */
ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
chip->ctar_val = 0;
if (spi->mode & SPI_CPOL)
chip->ctar_val |= SPI_CTAR_CPOL;
if (spi->mode & SPI_CPHA)
chip->ctar_val |= SPI_CTAR_CPHA;
if (!spi_controller_is_target(dspi->ctlr)) {
chip->ctar_val |= SPI_CTAR_PCSSCK(pcssck) |
SPI_CTAR_CSSCK(cssck) |
SPI_CTAR_PASC(pasc) |
SPI_CTAR_ASC(asc) |
SPI_CTAR_PBR(pbr) |
SPI_CTAR_BR(br);
if (spi->mode & SPI_LSB_FIRST)
chip->ctar_val |= SPI_CTAR_LSBFE;
}
gpiod_direction_output(spi_get_csgpiod(spi, 0), false);
dspi_deassert_cs(spi, &cs);
spi_set_ctldata(spi, chip);
return 0;
}
static void dspi_cleanup(struct spi_device *spi)
{
struct chip_data *chip = spi_get_ctldata(spi);
dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
spi->controller->bus_num, spi_get_chipselect(spi, 0));
kfree(chip);
}
static const struct of_device_id fsl_dspi_dt_ids[] = {
{
.compatible = "fsl,vf610-dspi",
.data = &devtype_data[VF610],
}, {
.compatible = "fsl,ls1021a-v1.0-dspi",
.data = &devtype_data[LS1021A],
}, {
.compatible = "fsl,ls1012a-dspi",
.data = &devtype_data[LS1012A],
}, {
.compatible = "fsl,ls1028a-dspi",
.data = &devtype_data[LS1028A],
}, {
.compatible = "fsl,ls1043a-dspi",
.data = &devtype_data[LS1043A],
}, {
.compatible = "fsl,ls1046a-dspi",
.data = &devtype_data[LS1046A],
}, {
.compatible = "fsl,ls2080a-dspi",
.data = &devtype_data[LS2080A],
}, {
.compatible = "fsl,ls2085a-dspi",
.data = &devtype_data[LS2085A],
}, {
.compatible = "fsl,lx2160a-dspi",
.data = &devtype_data[LX2160A],
},
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
#ifdef CONFIG_PM_SLEEP
static int dspi_suspend(struct device *dev)
{
struct fsl_dspi *dspi = dev_get_drvdata(dev);
if (dspi->irq)
disable_irq(dspi->irq);
spi_controller_suspend(dspi->ctlr);
clk_disable_unprepare(dspi->clk);
pinctrl_pm_select_sleep_state(dev);
return 0;
}
static int dspi_resume(struct device *dev)
{
struct fsl_dspi *dspi = dev_get_drvdata(dev);
int ret;
pinctrl_pm_select_default_state(dev);
ret = clk_prepare_enable(dspi->clk);
if (ret)
return ret;
spi_controller_resume(dspi->ctlr);
if (dspi->irq)
enable_irq(dspi->irq);
return 0;
}
#endif /* CONFIG_PM_SLEEP */
static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
static const struct regmap_range dspi_volatile_ranges[] = {
regmap_reg_range(SPI_MCR, SPI_TCR),
regmap_reg_range(SPI_SR, SPI_SR),
regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
};
static const struct regmap_access_table dspi_volatile_table = {
.yes_ranges = dspi_volatile_ranges,
.n_yes_ranges = ARRAY_SIZE(dspi_volatile_ranges),
};
static const struct regmap_config dspi_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.max_register = 0x88,
.volatile_table = &dspi_volatile_table,
};
static const struct regmap_range dspi_xspi_volatile_ranges[] = {
regmap_reg_range(SPI_MCR, SPI_TCR),
regmap_reg_range(SPI_SR, SPI_SR),
regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
regmap_reg_range(SPI_SREX, SPI_SREX),
};
static const struct regmap_access_table dspi_xspi_volatile_table = {
.yes_ranges = dspi_xspi_volatile_ranges,
.n_yes_ranges = ARRAY_SIZE(dspi_xspi_volatile_ranges),
};
static const struct regmap_config dspi_xspi_regmap_config[] = {
{
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.max_register = 0x13c,
.volatile_table = &dspi_xspi_volatile_table,
},
{
.name = "pushr",
.reg_bits = 16,
.val_bits = 16,
.reg_stride = 2,
.max_register = 0x2,
},
};
static int dspi_init(struct fsl_dspi *dspi)
{
unsigned int mcr;
/* Set idle states for all chip select signals to high */
mcr = SPI_MCR_PCSIS(GENMASK(dspi->ctlr->max_native_cs - 1, 0));
if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
mcr |= SPI_MCR_XSPI;
if (!spi_controller_is_target(dspi->ctlr))
mcr |= SPI_MCR_HOST;
regmap_write(dspi->regmap, SPI_MCR, mcr);
regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
switch (dspi->devtype_data->trans_mode) {
case DSPI_XSPI_MODE:
regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_CMDTCFE);
break;
case DSPI_DMA_MODE:
regmap_write(dspi->regmap, SPI_RSER,
SPI_RSER_TFFFE | SPI_RSER_TFFFD |
SPI_RSER_RFDFE | SPI_RSER_RFDFD);
break;
default:
dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
dspi->devtype_data->trans_mode);
return -EINVAL;
}
return 0;
}
static int dspi_target_abort(struct spi_controller *host)
{
struct fsl_dspi *dspi = spi_controller_get_devdata(host);
/*
* Terminate all pending DMA transactions for the SPI working
* in TARGET mode.
*/
if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
dmaengine_terminate_sync(dspi->dma->chan_rx);
dmaengine_terminate_sync(dspi->dma->chan_tx);
}
/* Clear the internal DSPI RX and TX FIFO buffers */
regmap_update_bits(dspi->regmap, SPI_MCR,
SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
return 0;
}
static int dspi_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
const struct regmap_config *regmap_config;
struct fsl_dspi_platform_data *pdata;
struct spi_controller *ctlr;
int ret, cs_num, bus_num = -1;
struct fsl_dspi *dspi;
struct resource *res;
void __iomem *base;
bool big_endian;
dspi = devm_kzalloc(&pdev->dev, sizeof(*dspi), GFP_KERNEL);
if (!dspi)
return -ENOMEM;
ctlr = spi_alloc_host(&pdev->dev, 0);
if (!ctlr)
return -ENOMEM;
spi_controller_set_devdata(ctlr, dspi);
platform_set_drvdata(pdev, dspi);
dspi->pdev = pdev;
dspi->ctlr = ctlr;
ctlr->setup = dspi_setup;
ctlr->transfer_one_message = dspi_transfer_one_message;
ctlr->dev.of_node = pdev->dev.of_node;
ctlr->cleanup = dspi_cleanup;
ctlr->target_abort = dspi_target_abort;
ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
ctlr->use_gpio_descriptors = true;
pdata = dev_get_platdata(&pdev->dev);
if (pdata) {
ctlr->num_chipselect = ctlr->max_native_cs = pdata->cs_num;
ctlr->bus_num = pdata->bus_num;
/* Only Coldfire uses platform data */
dspi->devtype_data = &devtype_data[MCF5441X];
big_endian = true;
} else {
ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
if (ret < 0) {
dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
goto out_ctlr_put;
}
ctlr->num_chipselect = ctlr->max_native_cs = cs_num;
of_property_read_u32(np, "bus-num", &bus_num);
ctlr->bus_num = bus_num;
if (of_property_read_bool(np, "spi-slave"))
ctlr->target = true;
dspi->devtype_data = of_device_get_match_data(&pdev->dev);
if (!dspi->devtype_data) {
dev_err(&pdev->dev, "can't get devtype_data\n");
ret = -EFAULT;
goto out_ctlr_put;
}
big_endian = of_device_is_big_endian(np);
}
if (big_endian) {
dspi->pushr_cmd = 0;
dspi->pushr_tx = 2;
} else {
dspi->pushr_cmd = 2;
dspi->pushr_tx = 0;
}
if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
else
ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(base)) {
ret = PTR_ERR(base);
goto out_ctlr_put;
}
if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
regmap_config = &dspi_xspi_regmap_config[0];
else
regmap_config = &dspi_regmap_config;
dspi->regmap = devm_regmap_init_mmio(&pdev->dev, base, regmap_config);
if (IS_ERR(dspi->regmap)) {
dev_err(&pdev->dev, "failed to init regmap: %ld\n",
PTR_ERR(dspi->regmap));
ret = PTR_ERR(dspi->regmap);
goto out_ctlr_put;
}
if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE) {
dspi->regmap_pushr = devm_regmap_init_mmio(
&pdev->dev, base + SPI_PUSHR,
&dspi_xspi_regmap_config[1]);
if (IS_ERR(dspi->regmap_pushr)) {
dev_err(&pdev->dev,
"failed to init pushr regmap: %ld\n",
PTR_ERR(dspi->regmap_pushr));
ret = PTR_ERR(dspi->regmap_pushr);
goto out_ctlr_put;
}
}
dspi->clk = devm_clk_get_enabled(&pdev->dev, "dspi");
if (IS_ERR(dspi->clk)) {
ret = PTR_ERR(dspi->clk);
dev_err(&pdev->dev, "unable to get clock\n");
goto out_ctlr_put;
}
ret = dspi_init(dspi);
if (ret)
goto out_ctlr_put;
dspi->irq = platform_get_irq(pdev, 0);
if (dspi->irq <= 0) {
dev_info(&pdev->dev,
"can't get platform irq, using poll mode\n");
dspi->irq = 0;
goto poll_mode;
}
init_completion(&dspi->xfer_done);
ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL,
IRQF_SHARED, pdev->name, dspi);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
goto out_ctlr_put;
}
poll_mode:
if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
ret = dspi_request_dma(dspi, res->start);
if (ret < 0) {
dev_err(&pdev->dev, "can't get dma channels\n");
goto out_free_irq;
}
}
ctlr->max_speed_hz =
clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
if (dspi->devtype_data->trans_mode != DSPI_DMA_MODE)
ctlr->ptp_sts_supported = true;
ret = spi_register_controller(ctlr);
if (ret != 0) {
dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
goto out_release_dma;
}
return ret;
out_release_dma:
dspi_release_dma(dspi);
out_free_irq:
if (dspi->irq)
free_irq(dspi->irq, dspi);
out_ctlr_put:
spi_controller_put(ctlr);
return ret;
}
static void dspi_remove(struct platform_device *pdev)
{
struct fsl_dspi *dspi = platform_get_drvdata(pdev);
/* Disconnect from the SPI framework */
spi_unregister_controller(dspi->ctlr);
/* Disable RX and TX */
regmap_update_bits(dspi->regmap, SPI_MCR,
SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF,
SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF);
/* Stop Running */
regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, SPI_MCR_HALT);
dspi_release_dma(dspi);
if (dspi->irq)
free_irq(dspi->irq, dspi);
}
static void dspi_shutdown(struct platform_device *pdev)
{
dspi_remove(pdev);
}
static struct platform_driver fsl_dspi_driver = {
.driver.name = DRIVER_NAME,
.driver.of_match_table = fsl_dspi_dt_ids,
.driver.pm = &dspi_pm,
.probe = dspi_probe,
.remove_new = dspi_remove,
.shutdown = dspi_shutdown,
};
module_platform_driver(fsl_dspi_driver);
MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRIVER_NAME);
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