/*===============================================================*\
| Project: RTEMS support for PGH360 |
+-----------------------------------------------------------------+
| Copyright (c) 2008 |
| Embedded Brains GmbH |
| Obere Lagerstr. 30 |
| D-82178 Puchheim |
| Germany |
| rtems@embedded-brains.de |
+-----------------------------------------------------------------+
| The license and distribution terms for this file may be |
| found in the file LICENSE in this distribution or at |
| |
| http://www.rtems.org/license/LICENSE. |
| |
+-----------------------------------------------------------------+
| this file contains the M360 SPI driver |
\*===============================================================*/
#include <stdlib.h>
#include <bsp.h>
#include <rtems/m68k/m68360.h>
#include <rtems/m68k/m360_spi.h>
#include <rtems/error.h>
#include <rtems/bspIo.h>
#include <errno.h>
#include <rtems/libi2c.h>
#undef DEBUG
static m360_spi_softc_t *m360_spi_softc_ptr;
/*
* this is a dummy receive buffer for sequences,
* where only send data are available
*/
uint8_t m360_spi_dummy_rxbuf[2];
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static rtems_status_code m360_spi_baud_to_mode
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| determine proper divider value |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
uint32_t baudrate, /* desired baudrate */
uint32_t *spimode /* result value */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| o = ok or error code |
\*=========================================================================*/
{
uint32_t divider;
uint16_t tmpmode = 0;
/*
* determine clock divider and DIV16 bit
*/
divider = m360_clock_rate/baudrate;
if (divider > 64) {
tmpmode = M360_SPMODE_DIV16;
divider /= 16;
}
if ((divider < 1) ||
(divider > 64)) {
return RTEMS_INVALID_NUMBER;
}
else {
tmpmode |= M360_SPMODE_PM(divider/4-1);
}
*spimode = tmpmode;
return RTEMS_SUCCESSFUL;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static rtems_status_code m360_spi_char_mode
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| determine proper value for character size |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
m360_spi_softc_t *softc_ptr, /* handle */
uint32_t bits_per_char, /* bits per character */
bool lsb_first, /* TRUE: send LSB first */
uint16_t *spimode /* result value */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| o = ok or error code |
\*=========================================================================*/
{
uint16_t tmpmode;
/*
* calculate data format
*/
if ((bits_per_char >= 4) &&
(bits_per_char <= 16)) {
tmpmode = M360_SPMODE_CLEN( bits_per_char-1);
}
else {
return RTEMS_INVALID_NUMBER;
}
*spimode = tmpmode;
return 0;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static int m360_spi_wait
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| wait for spi to become idle |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
m360_spi_softc_t *softc_ptr /* handle */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| o = ok or error code |
\*=========================================================================*/
{
uint16_t act_status;
rtems_status_code rc;
uint32_t tout;
#if defined(DEBUG)
printk("m360_spi_wait called... ");
#endif
if (softc_ptr->initialized) {
/*
* allow interrupts, when receiver is not empty
*/
m360.spim = (M360_SPIE_TXE | M360_SPIE_TXB |
M360_SPIE_BSY | M360_SPIE_MME);
rc = rtems_semaphore_obtain(softc_ptr->irq_sema_id,
RTEMS_WAIT,
RTEMS_NO_TIMEOUT);
if (rc != RTEMS_SUCCESSFUL) {
return rc;
}
}
else {
tout = 0;
do {
if (tout++ > 1000000) {
#if defined(DEBUG)
printk("... exit with RTEMS_TIMEOUT\r\n");
#endif
return RTEMS_TIMEOUT;
}
/*
* wait for SPI to terminate
*/
} while (!(m360.spie & M360_SPIE_TXB));
}
act_status = m360.spie;
if ((act_status & (M360_SPIE_TXE | M360_SPIE_TXB |
M360_SPIE_BSY | M360_SPIE_MME))!= M360_SPIE_TXB) {
#if defined(DEBUG)
printk("... exit with RTEMS_IO_ERROR,"
"act_status=0x%04x,mask=0x%04x,desired_status=0x%04x\r\n",
act_status,status_mask,desired_status);
#endif
return RTEMS_IO_ERROR;
}
#if defined(DEBUG)
printk("... exit OK\r\n");
#endif
return RTEMS_SUCCESSFUL;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static rtems_isr m360_spi_irq_handler
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| handle interrupts |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_vector_number v /* vector number */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| <none> |
\*=========================================================================*/
{
m360_spi_softc_t *softc_ptr = m360_spi_softc_ptr;
/*
* disable interrupt mask
*/
m360.spim = 0;
if (softc_ptr->initialized) {
rtems_semaphore_release(softc_ptr->irq_sema_id);
}
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static void m360_spi_install_irq_handler
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| (un-)install the interrupt handler |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
m360_spi_softc_t *softc_ptr, /* ptr to control structure */
int install /* TRUE: install, FALSE: remove */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| <none> |
\*=========================================================================*/
{
rtems_status_code rc = RTEMS_SUCCESSFUL;
/*
* (un-)install handler for SPI device
*/
if (install) {
/*
* create semaphore for IRQ synchronization
*/
rc = rtems_semaphore_create(rtems_build_name('s','p','i','s'),
0,
RTEMS_FIFO
| RTEMS_SIMPLE_BINARY_SEMAPHORE,
0,
&softc_ptr->irq_sema_id);
if (rc != RTEMS_SUCCESSFUL) {
rtems_panic("SPI: cannot create semaphore");
}
if (rc == RTEMS_SUCCESSFUL) {
rc = rtems_interrupt_catch (m360_spi_irq_handler,
(m360.cicr & 0xE0) | 0x05,
&softc_ptr->old_handler);
if (rc != RTEMS_SUCCESSFUL) {
rtems_panic("SPI: cannot install IRQ handler");
}
}
/*
* enable IRQ in CPIC
*/
if (rc == RTEMS_SUCCESSFUL) {
m360.cimr |= (1 << 5);
}
}
else {
rtems_isr_entry old_handler;
/*
* disable IRQ in CPIC
*/
if (rc == RTEMS_SUCCESSFUL) {
m360.cimr &= ~(1 << 5);
}
rc = rtems_interrupt_catch (softc_ptr->old_handler,
(m360.cicr & 0xE0) | 0x05,
&old_handler);
if (rc != RTEMS_SUCCESSFUL) {
rtems_panic("SPI: cannot uninstall IRQ handler");
}
/*
* delete sync semaphore
*/
if (softc_ptr->irq_sema_id != 0) {
rc = rtems_semaphore_delete(softc_ptr->irq_sema_id);
if (rc != RTEMS_SUCCESSFUL) {
rtems_panic("SPI: cannot delete semaphore");
}
}
}
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
rtems_status_code m360_spi_init
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| initialize the driver |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh /* bus specifier structure */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| o = ok or error code |
\*=========================================================================*/
{
m360_spi_softc_t *softc_ptr = &(((m360_spi_desc_t *)(bh))->softc);
rtems_status_code rc = RTEMS_SUCCESSFUL;
#if defined(DEBUG)
printk("m360_spi_init called... ");
#endif
/*
* init HW registers:
*/
/*
* FIXME: set default mode in SPMODE
*/
/*
* allocate BDs (1x RX, 1x TX)
*/
if (rc == RTEMS_SUCCESSFUL) {
softc_ptr->rx_bd = M360AllocateBufferDescriptors (1);
softc_ptr->tx_bd = M360AllocateBufferDescriptors (1);
if ((softc_ptr->rx_bd == NULL) ||
(softc_ptr->tx_bd == NULL)) {
rc = RTEMS_NO_MEMORY;
}
}
/*
* set parameter RAM
*/
m360.spip.rbase = (char *)softc_ptr->rx_bd - (char *)&m360;
m360.spip.tbase = (char *)softc_ptr->tx_bd - (char *)&m360;
m360.spip.rfcr = M360_RFCR_MOT | M360_RFCR_DMA_SPACE;
m360.spip.tfcr = M360_RFCR_MOT | M360_RFCR_DMA_SPACE;
m360.spip.mrblr = 2;
/*
* issue "InitRxTx" Command to CP
*/
M360ExecuteRISC (M360_CR_OP_INIT_RX_TX | M360_CR_CHAN_SPI);
/*
* init interrupt stuff
*/
if (rc == RTEMS_SUCCESSFUL) {
m360_spi_install_irq_handler(softc_ptr,TRUE);
}
if (rc == RTEMS_SUCCESSFUL) {
/*
* set up ports
* LINE PAR DIR DAT
* -----------------------
* MOSI 1 1 x
* MISO 1 1 x
* CLK 1 1 x
*/
/* set Port B Pin Assignment Register... */
m360.pbpar =
m360.pbpar
| M360_PB_SPI_MISO_MSK
| M360_PB_SPI_MOSI_MSK
| M360_PB_SPI_CLK_MSK;
/* set Port B Data Direction Register... */
m360.pbdir =
m360.pbdir
| M360_PB_SPI_MISO_MSK
| M360_PB_SPI_MOSI_MSK
| M360_PB_SPI_CLK_MSK;
}
/*
* mark, that we have initialized
*/
if (rc == RTEMS_SUCCESSFUL) {
softc_ptr->initialized = TRUE;
}
#if defined(DEBUG)
printk("... exit OK\r\n");
#endif
return rc;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static int m360_spi_read_write_bytes
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| transmit/receive some bytes from SPI device |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh, /* bus specifier structure */
unsigned char *rbuf, /* buffer to store bytes */
const unsigned char *tbuf, /* buffer to send bytes */
int len /* number of bytes to transceive */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| number of bytes received or (negative) error code |
\*=========================================================================*/
{
m360_spi_softc_t *softc_ptr = &(((m360_spi_desc_t *)(bh))->softc);
rtems_status_code rc = RTEMS_SUCCESSFUL;
int bc = 0;
#if defined(DEBUG)
printk("m360_spi_read_write_bytes called... ");
#endif
/*
* prepare RxBD
*/
if (rc == RTEMS_SUCCESSFUL) {
if (rbuf == NULL) {
/*
* no Tx buffer: receive to dummy buffer
*/
m360.spip.mrblr = sizeof(m360_spi_dummy_rxbuf);
softc_ptr->rx_bd->buffer = m360_spi_dummy_rxbuf;
softc_ptr->rx_bd->length = 0;
softc_ptr->rx_bd->status = (M360_BD_EMPTY | M360_BD_WRAP |
M360_BD_CONTINUOUS);
}
else {
m360.spip.mrblr = len;
softc_ptr->rx_bd->buffer = rbuf;
softc_ptr->rx_bd->length = 0;
softc_ptr->rx_bd->status = (M360_BD_EMPTY | M360_BD_WRAP);
}
}
/*
* prepare TxBD
*/
if (rc == RTEMS_SUCCESSFUL) {
if (tbuf == NULL) {
/*
* FIXME: no Tx buffer: transmit from dummy buffer
*/
softc_ptr->tx_bd->buffer = m360_spi_dummy_rxbuf;
softc_ptr->tx_bd->length = len;
softc_ptr->tx_bd->status = (M360_BD_READY | M360_BD_WRAP |
M360_BD_CONTINUOUS);
}
else {
softc_ptr->tx_bd->buffer = tbuf;
softc_ptr->tx_bd->length = len;
softc_ptr->tx_bd->status = (M360_BD_READY | M360_BD_WRAP);
}
}
if (rc == RTEMS_SUCCESSFUL) {
/*
* set START command
*/
m360.spcom = M360_SPCOM_STR;
/*
* wait for SPI to finish
*/
rc = m360_spi_wait(softc_ptr);
}
#if defined(DEBUG)
printk("... exit OK, rc=%d\r\n",bc);
#endif
return (rc == RTEMS_SUCCESSFUL) ? bc : -rc;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
int m360_spi_read_bytes
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| receive some bytes from SPI device |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh, /* bus specifier structure */
unsigned char *buf, /* buffer to store bytes */
int len /* number of bytes to receive */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| number of bytes received or (negative) error code |
\*=========================================================================*/
{
return m360_spi_read_write_bytes(bh,buf,NULL,len);
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
int m360_spi_write_bytes
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| send some bytes to SPI device |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh, /* bus specifier structure */
unsigned char *buf, /* buffer to send */
int len /* number of bytes to send */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| number of bytes sent or (negative) error code |
\*=========================================================================*/
{
return m360_spi_read_write_bytes(bh,NULL,buf,len);
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
rtems_status_code m360_spi_set_tfr_mode
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| set SPI to desired baudrate/clock mode/character mode |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh, /* bus specifier structure */
const rtems_libi2c_tfr_mode_t *tfr_mode /* transfer mode info */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| rtems_status_code |
\*=========================================================================*/
{
m360_spi_softc_t *softc_ptr = &(((m360_spi_desc_t *)(bh))->softc);
uint32_t spimode_baud,spimode;
rtems_status_code rc = RTEMS_SUCCESSFUL;
/*
* FIXME: set proper mode
*/
if (rc == RTEMS_SUCCESSFUL) {
rc = m360_spi_baud_to_mode(tfr_mode->baudrate,&spimode_baud);
}
if (rc == RTEMS_SUCCESSFUL) {
rc = m360_spi_char_mode(softc_ptr,
tfr_mode->bits_per_char,
tfr_mode->lsb_first,
&spimode);
}
if (rc == RTEMS_SUCCESSFUL) {
spimode |= spimode_baud;
spimode |= M360_SPMODE_MASTER; /* set master mode */
if (!tfr_mode->lsb_first) {
spimode |= M360_SPMODE_REV;
}
if (tfr_mode->clock_inv) {
spimode |= M360_SPMODE_CI;
}
if (tfr_mode->clock_phs) {
spimode |= M360_SPMODE_CP;
}
}
if (rc == RTEMS_SUCCESSFUL) {
/*
* disable SPI
*/
m360.spmode &= ~M360_SPMODE_EN;
/*
* set new mode and reenable SPI
*/
m360.spmode = spimode | M360_SPMODE_EN;
}
return rc;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
int m360_spi_ioctl
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| perform selected ioctl function for SPI |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh, /* bus specifier structure */
int cmd, /* ioctl command code */
void *arg /* additional argument array */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| rtems_status_code |
\*=========================================================================*/
{
int ret_val = -1;
switch(cmd) {
case RTEMS_LIBI2C_IOCTL_SET_TFRMODE:
ret_val =
-m360_spi_set_tfr_mode(bh,
(const rtems_libi2c_tfr_mode_t *)arg);
break;
case RTEMS_LIBI2C_IOCTL_READ_WRITE:
ret_val =
m360_spi_read_write_bytes(bh,
((rtems_libi2c_read_write_t *)arg)->rd_buf,
((rtems_libi2c_read_write_t *)arg)->wr_buf,
((rtems_libi2c_read_write_t *)arg)->byte_cnt);
break;
default:
ret_val = -RTEMS_NOT_DEFINED;
break;
}
return ret_val;
}
/*=========================================================================*\
| Board-specific adaptation functions |
\*=========================================================================*/
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static rtems_status_code bsp_spi_sel_addr
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| address a slave device on the bus |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh, /* bus specifier structure */
uint32_t addr, /* address to send on bus */
int rw /* 0=write,1=read */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| o = ok or error code |
\*=========================================================================*/
{
#if defined(PGH360)
/*
* select given device
*/
/*
* GPIO1[24] is SPI_A0
* GPIO1[25] is SPI_A1
* GPIO1[26] is SPI_A2
* set pins to address
*/
switch(addr) {
case PGH360_SPI_ADDR_EEPROM:
m360.pbdat &= ~PGH360_PB_SPI_EEP_CE_MSK;
break;
case PGH360_SPI_ADDR_DISP4_DATA:
m360.pbdat = (m360.pbdat
& ~(PGH360_PB_SPI_DISP4_CE_MSK |
PGH360_PB_SPI_DISP4_RS_MSK));
break;
case PGH360_SPI_ADDR_DISP4_CTRL:
m360.pbdat = (m360.pbdat
& ~(PGH360_PB_SPI_DISP4_CE_MSK)
| PGH360_PB_SPI_DISP4_RS_MSK);
break;
default:
return RTEMS_INVALID_NUMBER;
}
#endif /* PGH360 */
return RTEMS_SUCCESSFUL;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static rtems_status_code bsp_spi_send_start_dummy
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| dummy function, SPI has no start condition |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh /* bus specifier structure */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| o = ok or error code |
\*=========================================================================*/
{
return 0;
}
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
static rtems_status_code bsp_spi_send_stop
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| deselect SPI |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
rtems_libi2c_bus_t *bh /* bus specifier structure */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| o = ok or error code |
\*=========================================================================*/
{
#if defined(DEBUG)
printk("bsp_spi_send_stop called... ");
#endif
#if defined(PGH360)
m360.pbdat = (m360.pbdat
| PGH360_PB_SPI_DISP4_CE_MSK
| PGH360_PB_SPI_EEP_CE_MSK);
#endif
#if defined(DEBUG)
printk("... exit OK\r\n");
#endif
return 0;
}
/*=========================================================================*\
| list of handlers |
\*=========================================================================*/
rtems_libi2c_bus_ops_t bsp_spi_ops = {
init: m360_spi_init,
send_start: bsp_spi_send_start_dummy,
send_stop: bsp_spi_send_stop,
send_addr: bsp_spi_sel_addr,
read_bytes: m360_spi_read_bytes,
write_bytes: m360_spi_write_bytes,
ioctl: m360_spi_ioctl
};
static m360_spi_desc_t bsp_spi_bus_desc = {
{/* public fields */
ops: &bsp_spi_ops,
size: sizeof(bsp_spi_bus_desc)
},
{ /* our private fields */
initialized: FALSE
}
};
/*=========================================================================*\
| initialization |
\*=========================================================================*/
/*=========================================================================*\
| Function: |
\*-------------------------------------------------------------------------*/
rtems_status_code bsp_register_spi
(
/*-------------------------------------------------------------------------*\
| Purpose: |
| register SPI bus and devices |
+---------------------------------------------------------------------------+
| Input Parameters: |
\*-------------------------------------------------------------------------*/
void /* <none> */
)
/*-------------------------------------------------------------------------*\
| Return Value: |
| 0 or error code |
\*=========================================================================*/
{
int ret_code;
int spi_busno;
/*
* init I2C library (if not already done)
*/
rtems_libi2c_initialize ();
/*
* init port pins used to address/select SPI devices
*/
#if defined(PGH360)
/*
* set up ports
* LINE PAR DIR DAT
* -----------------------
* EEP_CE 0 1 act-high
* DISP4_CS 0 1 act-high
* DISP4_RS 0 1 active
*/
/* set Port B Pin Assignment Register... */
m360.pbpar =
(m360.pbpar
& ~(PGH360_PB_SPI_EEP_CE_MSK
| PGH360_PB_SPI_DISP4_CE_MSK
| PGH360_PB_SPI_DISP4_RS_MSK));
/* set Port B Data Direction Register... */
m360.pbdir =
m360.pbdir
| PGH360_PB_SPI_EEP_CE_MSK
| PGH360_PB_SPI_DISP4_CE_MSK
| PGH360_PB_SPI_DISP4_RS_MSK;
/* set Port B Data Register to inactive CE state */
m360.pbdat =
m360.pbdat
| PGH360_PB_SPI_DISP4_CE_MSK
| PGH360_PB_SPI_DISP4_RS_MSK;
#endif
/*
* register SPI bus
*/
ret_code = rtems_libi2c_register_bus("/dev/spi",
&(bsp_spi_bus_desc.bus_desc));
if (ret_code < 0) {
return -ret_code;
}
spi_busno = ret_code;
#if defined(PGH360)
/*
* register devices
*/
#if 0
ret_code = rtems_libi2c_register_drv(RTEMS_BSP_SPI_FLASH_DEVICE_NAME,
spi_flash_m25p40_rw_driver_descriptor,
spi_busno,0x00);
if (ret_code < 0) {
return -ret_code;
}
#endif
#endif /* defined(PGH360) */
/*
* FIXME: further drivers, when available
*/
return 0;
}
