u-boot/drivers/spi/cf_spi.c

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/*
*
* (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)
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <spi.h>
#include <malloc.h>
#include <asm/immap.h>
struct cf_spi_slave {
struct spi_slave slave;
uint baudrate;
int charbit;
};
int cfspi_xfer(struct spi_slave *slave, uint bitlen, const void *dout,
void *din, ulong flags);
struct spi_slave *cfspi_setup_slave(struct cf_spi_slave *cfslave, uint mode);
void cfspi_init(void);
void cfspi_tx(u32 ctrl, u16 data);
u16 cfspi_rx(void);
extern void cfspi_port_conf(void);
extern int cfspi_claim_bus(uint bus, uint cs);
extern void cfspi_release_bus(uint bus, uint cs);
DECLARE_GLOBAL_DATA_PTR;
#if defined(CONFIG_CF_DSPI)
/* DSPI specific mode */
#define SPI_MODE_MOD 0x00200000
#define SPI_DBLRATE 0x00100000
void cfspi_init(void)
{
volatile dspi_t *dspi = (dspi_t *) MMAP_DSPI;
cfspi_port_conf(); /* port configuration */
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;
/* Default setting in platform configuration */
#ifdef CONFIG_SYS_DSPI_CTAR0
dspi->ctar[0] = CONFIG_SYS_DSPI_CTAR0;
#endif
#ifdef CONFIG_SYS_DSPI_CTAR1
dspi->ctar[1] = CONFIG_SYS_DSPI_CTAR1;
#endif
#ifdef CONFIG_SYS_DSPI_CTAR2
dspi->ctar[2] = CONFIG_SYS_DSPI_CTAR2;
#endif
#ifdef CONFIG_SYS_DSPI_CTAR3
dspi->ctar[3] = CONFIG_SYS_DSPI_CTAR3;
#endif
#ifdef CONFIG_SYS_DSPI_CTAR4
dspi->ctar[4] = CONFIG_SYS_DSPI_CTAR4;
#endif
#ifdef CONFIG_SYS_DSPI_CTAR5
dspi->ctar[5] = CONFIG_SYS_DSPI_CTAR5;
#endif
#ifdef CONFIG_SYS_DSPI_CTAR6
dspi->ctar[6] = CONFIG_SYS_DSPI_CTAR6;
#endif
#ifdef CONFIG_SYS_DSPI_CTAR7
dspi->ctar[7] = CONFIG_SYS_DSPI_CTAR7;
#endif
}
void cfspi_tx(u32 ctrl, u16 data)
{
volatile dspi_t *dspi = (dspi_t *) MMAP_DSPI;
while ((dspi->sr & 0x0000F000) >= 4) ;
dspi->tfr = (ctrl | data);
}
u16 cfspi_rx(void)
{
volatile dspi_t *dspi = (dspi_t *) MMAP_DSPI;
while ((dspi->sr & 0x000000F0) == 0) ;
return (dspi->rfr & 0xFFFF);
}
int cfspi_xfer(struct spi_slave *slave, uint bitlen, const void *dout,
void *din, ulong flags)
{
struct cf_spi_slave *cfslave = (struct cf_spi_slave *)slave;
u16 *spi_rd16 = NULL, *spi_wr16 = NULL;
u8 *spi_rd = NULL, *spi_wr = NULL;
static u32 ctrl = 0;
uint len = bitlen >> 3;
if (cfslave->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 = (ctrl & 0xFF000000) | ((1 << slave->cs) << 16);
if (len > 1) {
int tmp_len = len - 1;
while (tmp_len--) {
if (dout != NULL) {
if (cfslave->charbit == 16)
cfspi_tx(ctrl, *spi_wr16++);
else
cfspi_tx(ctrl, *spi_wr++);
cfspi_rx();
}
if (din != NULL) {
cfspi_tx(ctrl, 0);
if (cfslave->charbit == 16)
*spi_rd16++ = cfspi_rx();
else
*spi_rd++ = cfspi_rx();
}
}
len = 1; /* remaining byte */
}
if ((flags & SPI_XFER_END) == SPI_XFER_END)
ctrl &= ~DSPI_TFR_CONT;
if (len) {
if (dout != NULL) {
if (cfslave->charbit == 16)
cfspi_tx(ctrl, *spi_wr16);
else
cfspi_tx(ctrl, *spi_wr);
cfspi_rx();
}
if (din != NULL) {
cfspi_tx(ctrl, 0);
if (cfslave->charbit == 16)
*spi_rd16 = cfspi_rx();
else
*spi_rd = cfspi_rx();
}
} else {
/* dummy read */
cfspi_tx(ctrl, 0);
cfspi_rx();
}
return 0;
}
struct spi_slave *cfspi_setup_slave(struct cf_spi_slave *cfslave, uint mode)
{
/*
* bit definition for 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
*/
volatile dspi_t *dspi = (dspi_t *) MMAP_DSPI;
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 = 0x7FFFFFFF, baud_speed;
u32 bus_setup = 0;
tmp = (prescaler[3] * scaler[15]);
/* Maximum and minimum baudrate it can handle */
if ((cfslave->baudrate > (gd->bus_clk >> 1)) ||
(cfslave->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 NULL;
}
/* Activate Double Baud when it exceed 1/4 the bus clk */
if ((CONFIG_SYS_DSPI_CTAR0 & DSPI_CTAR_DBR) ||
(cfslave->baudrate > (gd->bus_clk / (prescaler[0] * scaler[0])))) {
bus_setup |= DSPI_CTAR_DBR;
dbr = 1;
}
if (mode & SPI_CPOL)
bus_setup |= DSPI_CTAR_CPOL;
if (mode & SPI_CPHA)
bus_setup |= DSPI_CTAR_CPHA;
if (mode & SPI_LSB_FIRST)
bus_setup |= DSPI_CTAR_LSBFE;
/* Overwrite default value set in platform configuration file */
if (mode & SPI_MODE_MOD) {
if ((mode & 0xF0000000) == 0)
bus_setup |=
dspi->ctar[cfslave->slave.bus] & 0x78000000;
else
bus_setup |= ((mode & 0xF0000000) >> 1);
/*
* Check to see if it is enabled by default in platform
* config, or manual setting passed by mode parameter
*/
if (mode & SPI_DBLRATE) {
bus_setup |= DSPI_CTAR_DBR;
dbr = 1;
}
bus_setup |= (mode & 0x0FC00000) >> 4; /* PSCSCK, PASC, PDT */
bus_setup |= (mode & 0x000FFF00) >> 4; /* CSSCK, ASC, DT */
} else
bus_setup |= (dspi->ctar[cfslave->slave.bus] & 0x78FCFFF0);
cfslave->charbit =
((dspi->ctar[cfslave->slave.bus] & 0x78000000) ==
0x78000000) ? 16 : 8;
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 > cfslave->baudrate)
diff = tmp - cfslave->baudrate;
else
diff = cfslave->baudrate - tmp;
if (diff < bestmatch) {
bestmatch = diff;
best_i = i;
best_j = j;
}
}
}
bus_setup |= (DSPI_CTAR_PBR(best_i) | DSPI_CTAR_BR(best_j));
dspi->ctar[cfslave->slave.bus] = bus_setup;
return &cfslave->slave;
}
#endif /* CONFIG_CF_DSPI */
#ifdef CONFIG_CF_QSPI
/* 52xx, 53xx */
#endif /* CONFIG_CF_QSPI */
#ifdef CONFIG_CMD_SPI
int spi_cs_is_valid(unsigned int bus, unsigned int cs)
{
if (((cs >= 0) && (cs < 8)) && ((bus >= 0) && (bus < 8)))
return 1;
else
return 0;
}
void spi_init_f(void)
{
}
void spi_init_r(void)
{
}
void spi_init(void)
{
cfspi_init();
}
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct cf_spi_slave *cfslave;
if (!spi_cs_is_valid(bus, cs))
return NULL;
cfslave = malloc(sizeof(struct cf_spi_slave));
if (!cfslave)
return NULL;
cfslave->slave.bus = bus;
cfslave->slave.cs = cs;
cfslave->baudrate = max_hz;
/* specific setup */
return cfspi_setup_slave(cfslave, mode);
}
void spi_free_slave(struct spi_slave *slave)
{
free(slave);
}
int spi_claim_bus(struct spi_slave *slave)
{
return cfspi_claim_bus(slave->bus, slave->cs);
}
void spi_release_bus(struct spi_slave *slave)
{
cfspi_release_bus(slave->bus, slave->cs);
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
void *din, unsigned long flags)
{
return cfspi_xfer(slave, bitlen, dout, din, flags);
}
#endif /* CONFIG_CMD_SPI */