Ticket #1489: bfinspi.patch

Index: c/src/lib/libcpu/bfin/ChangeLog
===================================================================
RCS file: /usr1/CVS/rtems/c/src/lib/libcpu/bfin/ChangeLog,v
retrieving revision 1.13
diff -c -3 -p -r1.13 ChangeLog
*** c/src/lib/libcpu/bfin/ChangeLog     11 Dec 2009 04:15:58 -0000      1.13
--- c/src/lib/libcpu/bfin/ChangeLog     10 Jan 2010 22:12:55 -0000
***************
*** 1,3 ****
--- 1,10 ----
+ 2010-01-10    Allan Hessenflow <allanh@kallisti.com
+ 
+       * serial/spi.c, serial/spi.h:
+       Fill in skeleton with functional SPI master code.
+       * include/spiRegs.h:
+       Correct spi shadow register declaration.
+ 
  2009-12-11    Ralf Corsépius <ralf.corsepius@rtems.org>
  
        * serial/uart.c:
Index: c/src/lib/libcpu/bfin/README
===================================================================
RCS file: /usr1/CVS/rtems/c/src/lib/libcpu/bfin/README,v
retrieving revision 1.1
diff -c -3 -p -r1.1 README
*** c/src/lib/libcpu/bfin/README        15 Aug 2008 20:18:40 -0000      1.1
--- c/src/lib/libcpu/bfin/README        10 Jan 2010 22:12:55 -0000
*************** It is assumed that bsp.h includes <libcp
*** 9,15 ****
  the processor type.  This is how the libcpu modules determine which
  processor variant they're being built for.
  
! serial/spi* and serial/sport* are currently just placeholders.
! serial/twi* does not contain enough code to do anything useful;
! it is however a start at an I2C driver.
  
--- 9,15 ----
  the processor type.  This is how the libcpu modules determine which
  processor variant they're being built for.
  
! serial/sport* is currently just a placeholders.  serial/twi* does not
! contain enough code to do anything useful; it is however a start at an
! I2C driver.
  
Index: c/src/lib/libcpu/bfin/include/spiRegs.h
===================================================================
RCS file: /usr1/CVS/rtems/c/src/lib/libcpu/bfin/include/spiRegs.h,v
retrieving revision 1.1
diff -c -3 -p -r1.1 spiRegs.h
*** c/src/lib/libcpu/bfin/include/spiRegs.h     15 Aug 2008 20:18:41 -0000      1.1
--- c/src/lib/libcpu/bfin/include/spiRegs.h     10 Jan 2010 22:12:55 -0000
***************
*** 22,28 ****
  #define SPI_TDBR_OFFSET                               0x000c
  #define SPI_RDBR_OFFSET                               0x0010
  #define SPI_BAUD_OFFSET                               0x0014
! #define SPI_SHADOW                                    0x0018
  
  
  /* register fields */
--- 22,28 ----
  #define SPI_TDBR_OFFSET                               0x000c
  #define SPI_RDBR_OFFSET                               0x0010
  #define SPI_BAUD_OFFSET                               0x0014
! #define SPI_SHADOW_OFFSET                             0x0018
  
  
  /* register fields */
Index: c/src/lib/libcpu/bfin/serial/spi.c
===================================================================
RCS file: /usr1/CVS/rtems/c/src/lib/libcpu/bfin/serial/spi.c,v
retrieving revision 1.2
diff -c -3 -p -r1.2 spi.c
*** c/src/lib/libcpu/bfin/serial/spi.c  30 Nov 2009 05:03:49 -0000      1.2
--- c/src/lib/libcpu/bfin/serial/spi.c  10 Jan 2010 22:12:55 -0000
***************
*** 1,8 ****
- /* placeholder (just a shell) */
- 
  /*  SPI driver for Blackfin
   *
!  *  Copyright (c) 2008 Kallisti Labs, Los Gatos, CA, USA
   *             written by Allan Hessenflow <allanh@kallisti.com>
   *
   *  The license and distribution terms for this file may be
--- 1,6 ----
  /*  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
***************
*** 12,109 ****
   *  $Id: spi.c,v 1.2 2009/11/30 05:03:49 ralf Exp $
   */
  
- 
  #include <stdlib.h>
! #include <rtems.h>
  #include <rtems/libi2c.h>
- 
  #include <libcpu/spiRegs.h>
  #include "spi.h"
  
  
! static rtems_status_code spiInit(rtems_libi2c_bus_t *bus) {
!   bfin_spi_softc_t *softc;
!   rtems_status_code status;
  
!   softc = &(((bfin_spi_desc_t *)(bus))->softc);
! 
!   status = rtems_semaphore_create(rtems_build_name('s','p','i','s'),
                                    0,
                                    RTEMS_FIFO | RTEMS_SIMPLE_BINARY_SEMAPHORE,
                                    0,
!                                   &softc->irq_sema_id);
  
!   return status;
  }
  
! static rtems_status_code spiSendStart(rtems_libi2c_bus_t *bus) {
!   bfin_spi_softc_t *softc;
!   rtems_status_code status;
! 
!   status = RTEMS_SUCCESSFUL;
!   softc = &(((bfin_spi_desc_t *)(bus))->softc);
  
!   return status;
  }
  
! static rtems_status_code spiSendStop(rtems_libi2c_bus_t *bus) {
!   bfin_spi_softc_t *softc;
!   rtems_status_code status;
  
!   status = RTEMS_SUCCESSFUL;
!   softc = &(((bfin_spi_desc_t *)(bus))->softc);
! 
!   return status;
  }
  
! static rtems_status_code spiSendAddr(rtems_libi2c_bus_t *bus,
!                                      uint32_t addr, int rw) {
!   bfin_spi_softc_t *softc;
!   rtems_status_code status;
! 
!   status = RTEMS_SUCCESSFUL;
!   softc = &(((bfin_spi_desc_t *)(bus))->softc);
  
!   return status;
  }
  
! static int spiReadBytes(rtems_libi2c_bus_t *bus,
!                         unsigned char *buf, int len) {
!   bfin_spi_softc_t *softc;
  
!   softc = &(((bfin_spi_desc_t *)(bus))->softc);
  
!   return 0;
  }
  
- static int spiWriteBytes(rtems_libi2c_bus_t *bus,
-                          unsigned char *buf, int len) {
-   bfin_spi_softc_t *softc;
- 
-   softc = &(((bfin_spi_desc_t *)(bus))->softc);
- 
-   return 0;
- }
- 
- static int spiIoctl(rtems_libi2c_bus_t *bus, int cmd, void *arg) {
-   bfin_spi_softc_t *softc;
- 
-   softc = &(((bfin_spi_desc_t *)(bus))->softc);
- 
- 
-   return 0;
- }
- 
- void bfin_spi_isr(int source) {
- }
- 
- rtems_libi2c_bus_ops_t bfin_spi_libi2c_bus_ops = {
-   init: spiInit,
-   send_start: spiSendStart,
-   send_stop: spiSendStop,
-   send_addr: spiSendAddr,
-   read_bytes: spiReadBytes,
-   write_bytes: spiWriteBytes,
-   ioctl: spiIoctl
- };
- 
--- 10,242 ----
   *  $Id: spi.c,v 1.2 2009/11/30 05:03:49 ralf Exp $
   */
  
  #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 "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;
  }
  
Index: c/src/lib/libcpu/bfin/serial/spi.h
===================================================================
RCS file: /usr1/CVS/rtems/c/src/lib/libcpu/bfin/serial/spi.h,v
retrieving revision 1.3
diff -c -3 -p -r1.3 spi.h
*** c/src/lib/libcpu/bfin/serial/spi.h  30 Nov 2009 05:03:49 -0000      1.3
--- c/src/lib/libcpu/bfin/serial/spi.h  10 Jan 2010 22:12:55 -0000
***************
*** 1,9 ****
- /* placeholder (just a shell) */
- 
  /*
   *  RTEMS driver for Blackfin SPI
   *
!  *  COPYRIGHT (c) 2008 Kallisti Labs, Los Gatos, CA, USA
   *            written by Allan Hessenflow <allanh@kallisti.com>
   *
   *  The license and distribution terms for this file may be
--- 1,7 ----
  /*
   *  RTEMS driver for Blackfin SPI
   *
!  *  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
***************
*** 13,52 ****
   *  $Id: spi.h,v 1.3 2009/11/30 05:03:49 ralf Exp $
   */
  
! 
! #ifndef _spi_h_
! #define _spi_h_
! 
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
- 
  typedef struct {
!   /* parameters provided by bsp */
!   uint32_t freq;
!   void    *base;
!   bool     fast;
!   /* internal use */
!   rtems_id irq_sema_id;
! } bfin_spi_softc_t;
  
  typedef struct {
    rtems_libi2c_bus_t bus;
!   bfin_spi_softc_t softc;
! } bfin_spi_desc_t;
  
  
! extern rtems_libi2c_bus_ops_t bfin_spi_libi2c_bus_ops;
  
  
! void bfin_spi_isr(int source);
  
  
  #ifdef __cplusplus
  }
  #endif
  
- #endif /* _spi_h_ */
  
--- 11,55 ----
   *  $Id: spi.h,v 1.3 2009/11/30 05:03:49 ralf Exp $
   */
  
! #ifndef _spi_h
! #define _spi_h
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  typedef struct {
!   void *base;
!   /* remaining entries are for internal use */
!   rtems_id sem;
!   int bytes_per_word;
!   uint16_t idle_pattern;
!   uint8_t *rd_ptr;
!   const uint8_t *wr_ptr;
!   int len;
! } bfin_spi_state_t;
  
  typedef struct {
    rtems_libi2c_bus_t bus;
!   bfin_spi_state_t p;
! } bfin_spi_bus_t;
! 
! 
! void bfin_spi_isr(int v);
  
+ rtems_status_code bfin_spi_init(rtems_libi2c_bus_t *bus);
  
! rtems_status_code bfin_spi_send_start(rtems_libi2c_bus_t *bus);
  
+ int bfin_spi_read_bytes(rtems_libi2c_bus_t *bus, unsigned char *buf, int len);
  
! int bfin_spi_write_bytes(rtems_libi2c_bus_t *bus, unsigned char *buf, int len);
  
+ int bfin_spi_ioctl(rtems_libi2c_bus_t *bus, int cmd, void *arg);
  
  #ifdef __cplusplus
  }
  #endif
  
  
+ #endif /* _spi_h */