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-rw-r--r--c/src/lib/libcpu/bfin/serial/spi.c240
1 files changed, 0 insertions, 240 deletions
diff --git a/c/src/lib/libcpu/bfin/serial/spi.c b/c/src/lib/libcpu/bfin/serial/spi.c
deleted file mode 100644
index e1024e8d10..0000000000
--- a/c/src/lib/libcpu/bfin/serial/spi.c
+++ /dev/null
@@ -1,240 +0,0 @@
-/* SPI driver for Blackfin
- *
- * Copyright (c) 2010 Kallisti Labs, Los Gatos, CA, USA
- * written by Allan Hessenflow <allanh@kallisti.com>
- *
- * 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.
- */
-
-#include <stdlib.h>
-#include <bsp.h>
-#include <rtems/error.h>
-#include <rtems/bspIo.h>
-#include <errno.h>
-#include <rtems/libi2c.h>
-#include <libcpu/spiRegs.h>
-#include <libcpu/spi.h>
-
-
-#ifndef BFIN_REG16
-#define BFIN_REG16(base, offset) \
- (*((uint16_t volatile *) ((uint8_t *)(base) + (offset))))
-#endif
-
-
-static bfin_spi_state_t *bfin_spi;
-
-
-void bfin_spi_isr(int v) {
- bfin_spi_state_t *state;
- uint16_t r;
-
- state = bfin_spi;
- if (state->len > state->bytes_per_word) {
- if (state->wr_ptr) {
- if (state->bytes_per_word == 2)
- r = *(uint16_t *) state->wr_ptr;
- else
- r = (uint16_t) *state->wr_ptr;
- state->wr_ptr += state->bytes_per_word;
- } else
- r = state->idle_pattern;
- BFIN_REG16(state->base, SPI_TDBR_OFFSET) = r;
- }
- state->len -= state->bytes_per_word;
- if (state->len <= 0) {
- /*
- The transfers are done, so I don't want to kick off another
- transfer or get any more interrupts. Reading the last word from
- SPI_SHADOW instead of SPI_RDBR should prevent it from triggering
- another transfer, but that doesn't clear the interrupt flag. I
- could mask the interrupt in the SIC, but that would preclude ever
- using the DMA channel that shares the interrupt independently (and
- they might just share it with something more important in some other
- member of the Blackfin family). And who knows what problems it
- might cause in this code potentially dealing with that still pended
- interrupt at the beginning of the next transfer.
-
- So instead I disable the SPI interface, read the data from RDBR
- (thus clearing the interrupt but not triggering another transfer
- since the interface is disabled), then re-eanble the interface.
- This has the problem that the bf537 tri-states the SPI signals
- while the interface is disabled. Either adding pull-ups on at
- least the chip select signals, or using GPIOs for them so they're
- not controlled by the SPI module, would be correct fixes for that
- (really pull-ups/downs should be added to the SPI CLK and MOSI
- signals as well to insure they cannot float into some region that
- causes input structures to consume excessive power). Or they can
- all be left alone, assuming that there's enough capacitance on the
- lines to prevent any problems for the short time they're being left
- disabled.
-
- An alternative approach I attempted involved switching TIMOD
- between RDBR and TDBR when starting and finishing a transfer, but
- I didn't get anywhere with that. In my limited testing TIMOD TDBR
- wasn't behaving as I expected it to, but maybe with more
- experimentation I'd find some solution there. However I'm out
- of time for this project, at least for now.
- */
-
- BFIN_REG16(state->base, SPI_CTL_OFFSET) &= ~SPI_CTL_SPE;
- r = BFIN_REG16(state->base, SPI_RDBR_OFFSET);
- BFIN_REG16(state->base, SPI_CTL_OFFSET) |= SPI_CTL_SPE;
- rtems_semaphore_release(state->sem);
- } else
- r = BFIN_REG16(state->base, SPI_RDBR_OFFSET);
-
- if (state->rd_ptr) {
- if (state->bytes_per_word == 2)
- *(uint16_t *) state->rd_ptr = r;
- else
- *state->rd_ptr = (uint8_t) r;
- state->rd_ptr += state->bytes_per_word;
- }
-}
-
-static rtems_status_code setTFRMode(rtems_libi2c_bus_t *bus,
- const rtems_libi2c_tfr_mode_t *tfrMode) {
- rtems_status_code result;
- bfin_spi_state_t *state;
- uint32_t divisor;
- uint16_t ctrl;
-
- result = RTEMS_SUCCESSFUL;
- state = &((bfin_spi_bus_t *) bus)->p;
-
- if (result == RTEMS_SUCCESSFUL) {
- if (tfrMode->bits_per_char != 8 &&
- tfrMode->bits_per_char != 16)
- result = RTEMS_INVALID_NUMBER;
- if (tfrMode->baudrate <= 0)
- result = RTEMS_INVALID_NUMBER;
- }
- if (result == RTEMS_SUCCESSFUL) {
- divisor = (SCLK / 2 + tfrMode->baudrate - 1) /
- tfrMode->baudrate;
- if (divisor < 2)
- divisor = 2;
- else if (divisor > 65535)
- result = RTEMS_INVALID_NUMBER;
- }
- if (result == RTEMS_SUCCESSFUL) {
- state->idle_pattern = (uint16_t) tfrMode->idle_char;
- state->bytes_per_word = (tfrMode->bits_per_char > 8) ? 2 : 1;
- BFIN_REG16(state->base, SPI_BAUD_OFFSET) = divisor;
- ctrl = BFIN_REG16(state->base, SPI_CTL_OFFSET);
- if (tfrMode->lsb_first)
- ctrl |= SPI_CTL_LSBF;
- else
- ctrl &= ~SPI_CTL_LSBF;
- if (tfrMode->bits_per_char > 8)
- ctrl |= SPI_CTL_SIZE;
- else
- ctrl &= ~SPI_CTL_SIZE;
- if (tfrMode->clock_inv)
- ctrl |= SPI_CTL_CPOL;
- else
- ctrl &= ~SPI_CTL_CPOL;
- if (tfrMode->clock_phs)
- ctrl |= SPI_CTL_CPHA;
- else
- ctrl &= ~SPI_CTL_CPHA;
- BFIN_REG16(state->base, SPI_CTL_OFFSET) = ctrl;
- }
-
- return result;
-}
-
-static int readWrite(rtems_libi2c_bus_t *bus, uint8_t *rdBuf,
- const uint8_t *wrBuf, int len) {
- rtems_status_code result;
- bfin_spi_state_t *state;
- uint16_t r;
-
- result = RTEMS_SUCCESSFUL;
- state = &((bfin_spi_bus_t *) bus)->p;
-
- if (len) {
- state->rd_ptr = rdBuf;
- state->wr_ptr = wrBuf;
- state->len = len;
- if (state->wr_ptr) {
- if (state->bytes_per_word == 2)
- r = *(uint16_t *) state->wr_ptr;
- else
- r = (uint16_t) *state->wr_ptr;
- state->wr_ptr += state->bytes_per_word;
- } else
- r = state->idle_pattern;
- BFIN_REG16(state->base, SPI_TDBR_OFFSET) = r;
- BFIN_REG16(state->base, SPI_RDBR_OFFSET); /* trigger */
- /* wait until done */
- do {
- result = rtems_semaphore_obtain(state->sem, RTEMS_WAIT, 100);
- } while (result == RTEMS_SUCCESSFUL && state->len > 0);
- }
-
- return (result == RTEMS_SUCCESSFUL) ? len : -result;
-}
-
-
-rtems_status_code bfin_spi_init(rtems_libi2c_bus_t *bus) {
- rtems_status_code result;
- bfin_spi_state_t *state;
-
- state = &((bfin_spi_bus_t *) bus)->p;
-
- BFIN_REG16(state->base, SPI_CTL_OFFSET) = SPI_CTL_SPE |
- SPI_CTL_MSTR |
- SPI_CTL_CPHA |
- SPI_CTL_TIMOD_RDBR;
-
- result = rtems_semaphore_create(rtems_build_name('s','p','i','s'),
- 0,
- RTEMS_FIFO | RTEMS_SIMPLE_BINARY_SEMAPHORE,
- 0,
- &state->sem);
- if (result == RTEMS_SUCCESSFUL)
- bfin_spi = state; /* for isr */
-
- return result;
-}
-
-rtems_status_code bfin_spi_send_start(rtems_libi2c_bus_t *bus) {
-
- return RTEMS_SUCCESSFUL;
-}
-
-int bfin_spi_read_bytes(rtems_libi2c_bus_t *bus, unsigned char *buf, int len) {
-
- return readWrite(bus, buf, NULL, len);
-}
-
-int bfin_spi_write_bytes(rtems_libi2c_bus_t *bus, unsigned char *buf, int len) {
-
- return readWrite(bus, NULL, buf, len);
-}
-
-int bfin_spi_ioctl(rtems_libi2c_bus_t *bus, int cmd, void *arg) {
- int result;
-
- result = -RTEMS_NOT_DEFINED;
- switch(cmd) {
- case RTEMS_LIBI2C_IOCTL_SET_TFRMODE:
- result = -setTFRMode(bus, (const rtems_libi2c_tfr_mode_t *) arg);
- break;
- case RTEMS_LIBI2C_IOCTL_READ_WRITE:
- result = readWrite(bus,
- ((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:
- break;
- }
-
- return result;
-}
-
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