u-boot/drivers/spi/cf_spi.c

461 lines
11 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0+
/*
*
* (C) Copyright 2000-2003
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* Copyright (C) 2004-2009 Freescale Semiconductor, Inc.
* TsiChung Liew (Tsi-Chung.Liew@freescale.com)
*
* Support for DM and DT, non-DM code removed.
* Copyright (C) 2018 Angelo Dureghello <angelo@sysam.it>
*
* TODO: fsl_dspi.c should work as a driver for the DSPI module.
*/
#include <common.h>
#include <dm.h>
#include <log.h>
#include <dm/platform_data/spi_coldfire.h>
#include <spi.h>
#include <malloc.h>
#include <asm/coldfire/dspi.h>
#include <asm/io.h>
struct coldfire_spi_priv {
struct dspi *regs;
uint baudrate;
int mode;
int charbit;
};
DECLARE_GLOBAL_DATA_PTR;
#ifndef CONFIG_SPI_IDLE_VAL
#if defined(CONFIG_SPI_MMC)
#define CONFIG_SPI_IDLE_VAL 0xFFFF
#else
#define CONFIG_SPI_IDLE_VAL 0x0
#endif
#endif
/*
* DSPI specific mode
*
* bit 31 - 28: Transfer size 3 to 16 bits
* 27 - 26: PCS to SCK delay prescaler
* 25 - 24: After SCK delay prescaler
* 23 - 22: Delay after transfer prescaler
* 21 : Allow overwrite for bit 31-22 and bit 20-8
* 20 : Double baud rate
* 19 - 16: PCS to SCK delay scaler
* 15 - 12: After SCK delay scaler
* 11 - 8: Delay after transfer scaler
* 7 - 0: SPI_CPHA, SPI_CPOL, SPI_LSB_FIRST
*/
#define SPI_MODE_MOD 0x00200000
#define SPI_MODE_DBLRATE 0x00100000
#define SPI_MODE_XFER_SZ_MASK 0xf0000000
#define SPI_MODE_DLY_PRE_MASK 0x0fc00000
#define SPI_MODE_DLY_SCA_MASK 0x000fff00
#define MCF_FRM_SZ_16BIT DSPI_CTAR_TRSZ(0xf)
#define MCF_DSPI_SPEED_BESTMATCH 0x7FFFFFFF
#define MCF_DSPI_MAX_CTAR_REGS 8
/* Default values */
#define MCF_DSPI_DEFAULT_SCK_FREQ 10000000
#define MCF_DSPI_DEFAULT_MAX_CS 4
#define MCF_DSPI_DEFAULT_MODE 0
#define MCF_DSPI_DEFAULT_CTAR (DSPI_CTAR_TRSZ(7) | \
DSPI_CTAR_PCSSCK_1CLK | \
DSPI_CTAR_PASC(0) | \
DSPI_CTAR_PDT(0) | \
DSPI_CTAR_CSSCK(0) | \
DSPI_CTAR_ASC(0) | \
DSPI_CTAR_DT(1) | \
DSPI_CTAR_BR(6))
#define MCF_CTAR_MODE_MASK (MCF_FRM_SZ_16BIT | \
DSPI_CTAR_PCSSCK(3) | \
DSPI_CTAR_PASC_7CLK | \
DSPI_CTAR_PDT(3) | \
DSPI_CTAR_CSSCK(0x0f) | \
DSPI_CTAR_ASC(0x0f) | \
DSPI_CTAR_DT(0x0f))
#define setup_ctrl(ctrl, cs) ((ctrl & 0xFF000000) | ((1 << cs) << 16))
static inline void cfspi_tx(struct coldfire_spi_priv *cfspi,
u32 ctrl, u16 data)
{
/*
* Need to check fifo level here
*/
while ((readl(&cfspi->regs->sr) & 0x0000F000) >= 0x4000)
;
writel(ctrl | data, &cfspi->regs->tfr);
}
static inline u16 cfspi_rx(struct coldfire_spi_priv *cfspi)
{
while ((readl(&cfspi->regs->sr) & 0x000000F0) == 0)
;
return readw(&cfspi->regs->rfr);
}
static int coldfire_spi_claim_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct coldfire_spi_priv *cfspi = dev_get_priv(bus);
struct dspi *dspi = cfspi->regs;
struct dm_spi_slave_platdata *slave_plat =
dev_get_parent_platdata(dev);
if ((in_be32(&dspi->sr) & DSPI_SR_TXRXS) != DSPI_SR_TXRXS)
return -1;
/* Clear FIFO and resume transfer */
clrbits_be32(&dspi->mcr, DSPI_MCR_CTXF | DSPI_MCR_CRXF);
dspi_chip_select(slave_plat->cs);
return 0;
}
static int coldfire_spi_release_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct coldfire_spi_priv *cfspi = dev_get_priv(bus);
struct dspi *dspi = cfspi->regs;
struct dm_spi_slave_platdata *slave_plat =
dev_get_parent_platdata(dev);
/* Clear FIFO */
clrbits_be32(&dspi->mcr, DSPI_MCR_CTXF | DSPI_MCR_CRXF);
dspi_chip_unselect(slave_plat->cs);
return 0;
}
static int coldfire_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din,
unsigned long flags)
{
struct udevice *bus = dev_get_parent(dev);
struct coldfire_spi_priv *cfspi = dev_get_priv(bus);
struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
u16 *spi_rd16 = NULL, *spi_wr16 = NULL;
u8 *spi_rd = NULL, *spi_wr = NULL;
static u32 ctrl;
uint len = bitlen >> 3;
if (cfspi->charbit == 16) {
bitlen >>= 1;
spi_wr16 = (u16 *)dout;
spi_rd16 = (u16 *)din;
} else {
spi_wr = (u8 *)dout;
spi_rd = (u8 *)din;
}
if ((flags & SPI_XFER_BEGIN) == SPI_XFER_BEGIN)
ctrl |= DSPI_TFR_CONT;
ctrl = setup_ctrl(ctrl, slave_plat->cs);
if (len > 1) {
int tmp_len = len - 1;
while (tmp_len--) {
if (dout) {
if (cfspi->charbit == 16)
cfspi_tx(cfspi, ctrl, *spi_wr16++);
else
cfspi_tx(cfspi, ctrl, *spi_wr++);
cfspi_rx(cfspi);
}
if (din) {
cfspi_tx(cfspi, ctrl, CONFIG_SPI_IDLE_VAL);
if (cfspi->charbit == 16)
*spi_rd16++ = cfspi_rx(cfspi);
else
*spi_rd++ = cfspi_rx(cfspi);
}
}
len = 1; /* remaining byte */
}
if (flags & SPI_XFER_END)
ctrl &= ~DSPI_TFR_CONT;
if (len) {
if (dout) {
if (cfspi->charbit == 16)
cfspi_tx(cfspi, ctrl, *spi_wr16);
else
cfspi_tx(cfspi, ctrl, *spi_wr);
cfspi_rx(cfspi);
}
if (din) {
cfspi_tx(cfspi, ctrl, CONFIG_SPI_IDLE_VAL);
if (cfspi->charbit == 16)
*spi_rd16 = cfspi_rx(cfspi);
else
*spi_rd = cfspi_rx(cfspi);
}
} else {
/* dummy read */
cfspi_tx(cfspi, ctrl, CONFIG_SPI_IDLE_VAL);
cfspi_rx(cfspi);
}
return 0;
}
static int coldfire_spi_set_speed(struct udevice *bus, uint max_hz)
{
struct coldfire_spi_priv *cfspi = dev_get_priv(bus);
struct dspi *dspi = cfspi->regs;
int prescaler[] = { 2, 3, 5, 7 };
int scaler[] = {
2, 4, 6, 8,
16, 32, 64, 128,
256, 512, 1024, 2048,
4096, 8192, 16384, 32768
};
int i, j, pbrcnt, brcnt, diff, tmp, dbr = 0;
int best_i, best_j, bestmatch = MCF_DSPI_SPEED_BESTMATCH, baud_speed;
u32 bus_setup;
cfspi->baudrate = max_hz;
/* Read current setup */
bus_setup = readl(&dspi->ctar[bus->seq]);
tmp = (prescaler[3] * scaler[15]);
/* Maximum and minimum baudrate it can handle */
if ((cfspi->baudrate > (gd->bus_clk >> 1)) ||
(cfspi->baudrate < (gd->bus_clk / tmp))) {
printf("Exceed baudrate limitation: Max %d - Min %d\n",
(int)(gd->bus_clk >> 1), (int)(gd->bus_clk / tmp));
return -1;
}
/* Activate Double Baud when it exceed 1/4 the bus clk */
if ((bus_setup & DSPI_CTAR_DBR) ||
(cfspi->baudrate > (gd->bus_clk / (prescaler[0] * scaler[0])))) {
bus_setup |= DSPI_CTAR_DBR;
dbr = 1;
}
/* Overwrite default value set in platform configuration file */
if (cfspi->mode & SPI_MODE_MOD) {
/*
* Check to see if it is enabled by default in platform
* config, or manual setting passed by mode parameter
*/
if (cfspi->mode & SPI_MODE_DBLRATE) {
bus_setup |= DSPI_CTAR_DBR;
dbr = 1;
}
}
pbrcnt = sizeof(prescaler) / sizeof(int);
brcnt = sizeof(scaler) / sizeof(int);
/* baudrate calculation - to closer value, may not be exact match */
for (best_i = 0, best_j = 0, i = 0; i < pbrcnt; i++) {
baud_speed = gd->bus_clk / prescaler[i];
for (j = 0; j < brcnt; j++) {
tmp = (baud_speed / scaler[j]) * (1 + dbr);
if (tmp > cfspi->baudrate)
diff = tmp - cfspi->baudrate;
else
diff = cfspi->baudrate - tmp;
if (diff < bestmatch) {
bestmatch = diff;
best_i = i;
best_j = j;
}
}
}
bus_setup &= ~(DSPI_CTAR_PBR(0x03) | DSPI_CTAR_BR(0x0f));
bus_setup |= (DSPI_CTAR_PBR(best_i) | DSPI_CTAR_BR(best_j));
writel(bus_setup, &dspi->ctar[bus->seq]);
return 0;
}
static int coldfire_spi_set_mode(struct udevice *bus, uint mode)
{
struct coldfire_spi_priv *cfspi = dev_get_priv(bus);
struct dspi *dspi = cfspi->regs;
u32 bus_setup = 0;
cfspi->mode = mode;
if (cfspi->mode & SPI_CPOL)
bus_setup |= DSPI_CTAR_CPOL;
if (cfspi->mode & SPI_CPHA)
bus_setup |= DSPI_CTAR_CPHA;
if (cfspi->mode & SPI_LSB_FIRST)
bus_setup |= DSPI_CTAR_LSBFE;
/* Overwrite default value set in platform configuration file */
if (cfspi->mode & SPI_MODE_MOD) {
if ((cfspi->mode & SPI_MODE_XFER_SZ_MASK) == 0)
bus_setup |=
readl(&dspi->ctar[bus->seq]) & MCF_FRM_SZ_16BIT;
else
bus_setup |=
((cfspi->mode & SPI_MODE_XFER_SZ_MASK) >> 1);
/* PSCSCK, PASC, PDT */
bus_setup |= (cfspi->mode & SPI_MODE_DLY_PRE_MASK) >> 4;
/* CSSCK, ASC, DT */
bus_setup |= (cfspi->mode & SPI_MODE_DLY_SCA_MASK) >> 4;
} else {
bus_setup |=
(readl(&dspi->ctar[bus->seq]) & MCF_CTAR_MODE_MASK);
}
cfspi->charbit =
((readl(&dspi->ctar[bus->seq]) & MCF_FRM_SZ_16BIT) ==
MCF_FRM_SZ_16BIT) ? 16 : 8;
setbits_be32(&dspi->ctar[bus->seq], bus_setup);
return 0;
}
static int coldfire_spi_probe(struct udevice *bus)
{
struct coldfire_spi_platdata *plat = dev_get_platdata(bus);
struct coldfire_spi_priv *cfspi = dev_get_priv(bus);
struct dspi *dspi = cfspi->regs;
int i;
cfspi->regs = (struct dspi *)plat->regs_addr;
cfspi->baudrate = plat->speed_hz;
cfspi->mode = plat->mode;
for (i = 0; i < MCF_DSPI_MAX_CTAR_REGS; i++) {
unsigned int ctar = 0;
if (plat->ctar[i][0] == 0)
break;
ctar = DSPI_CTAR_TRSZ(plat->ctar[i][0]) |
DSPI_CTAR_PCSSCK(plat->ctar[i][1]) |
DSPI_CTAR_PASC(plat->ctar[i][2]) |
DSPI_CTAR_PDT(plat->ctar[i][3]) |
DSPI_CTAR_CSSCK(plat->ctar[i][4]) |
DSPI_CTAR_ASC(plat->ctar[i][5]) |
DSPI_CTAR_DT(plat->ctar[i][6]) |
DSPI_CTAR_BR(plat->ctar[i][7]);
writel(ctar, &cfspi->regs->ctar[i]);
}
/* Default CTARs */
for (i = 0; i < MCF_DSPI_MAX_CTAR_REGS; i++)
writel(MCF_DSPI_DEFAULT_CTAR, &dspi->ctar[i]);
dspi->mcr = DSPI_MCR_MSTR | DSPI_MCR_CSIS7 | DSPI_MCR_CSIS6 |
DSPI_MCR_CSIS5 | DSPI_MCR_CSIS4 | DSPI_MCR_CSIS3 |
DSPI_MCR_CSIS2 | DSPI_MCR_CSIS1 | DSPI_MCR_CSIS0 |
DSPI_MCR_CRXF | DSPI_MCR_CTXF;
return 0;
}
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
static int coldfire_dspi_ofdata_to_platdata(struct udevice *bus)
{
fdt_addr_t addr;
struct coldfire_spi_platdata *plat = bus->platdata;
const void *blob = gd->fdt_blob;
int node = dev_of_offset(bus);
int *ctar, len;
addr = devfdt_get_addr(bus);
if (addr == FDT_ADDR_T_NONE)
return -ENOMEM;
plat->regs_addr = addr;
plat->num_cs = fdtdec_get_int(blob, node, "num-cs",
MCF_DSPI_DEFAULT_MAX_CS);
plat->speed_hz = fdtdec_get_int(blob, node, "spi-max-frequency",
MCF_DSPI_DEFAULT_SCK_FREQ);
plat->mode = fdtdec_get_int(blob, node, "spi-mode",
MCF_DSPI_DEFAULT_MODE);
memset(plat->ctar, 0, sizeof(plat->ctar));
ctar = (int *)fdt_getprop(blob, node, "ctar-params", &len);
if (ctar && len) {
int i, q, ctar_regs;
ctar_regs = len / sizeof(unsigned int) / MAX_CTAR_FIELDS;
if (ctar_regs > MAX_CTAR_REGS)
ctar_regs = MAX_CTAR_REGS;
for (i = 0; i < ctar_regs; i++) {
for (q = 0; q < MAX_CTAR_FIELDS; q++)
plat->ctar[i][q] = *ctar++;
}
}
debug("DSPI: regs=%pa, max-frequency=%d, num-cs=%d, mode=%d\n",
(void *)plat->regs_addr,
plat->speed_hz, plat->num_cs, plat->mode);
return 0;
}
static const struct udevice_id coldfire_spi_ids[] = {
{ .compatible = "fsl,mcf-dspi" },
{ }
};
#endif
static const struct dm_spi_ops coldfire_spi_ops = {
.claim_bus = coldfire_spi_claim_bus,
.release_bus = coldfire_spi_release_bus,
.xfer = coldfire_spi_xfer,
.set_speed = coldfire_spi_set_speed,
.set_mode = coldfire_spi_set_mode,
};
U_BOOT_DRIVER(coldfire_spi) = {
.name = "spi_coldfire",
.id = UCLASS_SPI,
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
.of_match = coldfire_spi_ids,
.ofdata_to_platdata = coldfire_dspi_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct coldfire_spi_platdata),
#endif
.probe = coldfire_spi_probe,
.ops = &coldfire_spi_ops,
.priv_auto_alloc_size = sizeof(struct coldfire_spi_priv),
};