scsi_decoder.c

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//_____  I N C L U D E S ___________________________________________________

#include "config.h"
#include "scsi_decoder.h"
#include "storage_task.h"
#include "conf_usb.h"
#include "lib_mcu/usb/usb_drv.h"
#include "modules/control_access/ctrl_status.h"
#include "modules/control_access/ctrl_access.h"


//_____ D E F I N I T I O N S ______________________________________________

U8  g_scsi_command[16];
U8  g_scsi_status;
U32 g_scsi_data_remaining;

code    U8    g_sbc_vendor_id[8]   = SBC_VENDOR_ID;
code    U8    g_sbc_product_id[16] = SBC_PRODUCT_ID;
code    U8    g_sbc_revision_id[4] = SBC_REVISION_ID;

extern  U8    usb_LUN;
extern  bit   ms_data_direction;
s_scsi_sense  g_scsi_sense;


code  struct sbc_st_std_inquiry_data sbc_std_inquiry_data =
{
   // Byte 0 : 0x00
   0x00,       // DeviceType: Direct-access device (SBC)
   0,          // PeripheralQualifier : Currently connected

   // Byte 1 : 0x80
   0,          // Reserved1
   1,          // RMB : Medium is removable (this bit must be at 1, else the medium isn't see on Windows)

   // Byte 2 : The code in the VERSION corresponds to a command set of DeviceType (here, Direct-access device - SBC)
   0x03,       // - 00h The device does not claim conformance to any standard.
               // - 03h The device complies to SPC (=SBC)
               // - 04h The device complies to SPC-2 (=SBC-2)
               // - 05h The device complies to SPC-3 (=SBC-2)
               // - 06h The device complies to SPC-4 (=SBC-3)

   // Byte 3 : 0x02
   2,          // Response data format
   0,          // NormACA
   0,          // Obsolete0
   0,          // AERC

   // Byte 4 : 0x1F
   // Byte 5 : 0x00
   // Byte 6 : 0x00
               // Reserved4[3]
   {
      0x1F,    // Additional Length (n-4)
      0,       // SCCS : SCC supported
      0
   },

   // Byte 7 : 0x00
   0,          // SoftReset
   0,          // CommandQueue
   0,          // Reserved5
   0,          // LinkedCommands
   0,          // Synchronous
   0,          // Wide16Bit
   0,          // Wide32Bit
   0,          // RelativeAddressing
};


static   void  send_informational_exceptions_page  (void);
static   void  send_read_write_error_recovery_page (U8);
static   void  sbc_header_mode_sense               ( Bool b_sense_10 , U8 u8_data_length );


//_____ D E C L A R A T I O N S ____________________________________________


Bool scsi_decode_command(void)
{
   Bool status;

   if (g_scsi_command[0] == SBC_CMD_WRITE_10)
   {
      Scsi_start_write_action();
      status = sbc_write_10();
      Scsi_stop_write_action();
      return status;
   }
   if (g_scsi_command[0] == SBC_CMD_READ_10 )
   {
      Scsi_start_read_action();
      status = sbc_read_10();
      Scsi_stop_read_action();
      return status;
   }

   switch (g_scsi_command[0])
   {
      case SBC_CMD_REQUEST_SENSE:               // 0x03 - Mandatory
      return sbc_request_sense();
      break;

      case SBC_CMD_INQUIRY:                     // 0x12 - Mandatory
      return sbc_inquiry();
      break;

      case SBC_CMD_TEST_UNIT_READY:             // 0x00 - Mandatory
      return sbc_test_unit_ready();
      break;

      case SBC_CMD_READ_CAPACITY:               // 0x25 - Mandatory
      return sbc_read_capacity();
      break;

      case SBC_CMD_MODE_SENSE_6:                // 0x1A - Optional
      return sbc_mode_sense( FALSE );
      break;

      case SBC_CMD_PREVENT_ALLOW_MEDIUM_REMOVAL:// 0x1E
      return sbc_prevent_allow_medium_removal();
      break;

      case SBC_CMD_VERIFY_10:                   // 0x2F - Optional
      sbc_lun_status_is_good();
      break;

      case SBC_CMD_MODE_SENSE_10:               // 0x5A - Optional
      return sbc_mode_sense( TRUE );
      break;

      case SBC_CMD_START_STOP_UNIT:             // 0x1B - Optional but ignored because this command is used by the Linux 2.4 kernel,
      sbc_lun_status_is_good();                 // for which we can not reply INVALID COMMAND, otherwise the disk will not mount.
      break;                                    

      case SBC_CMD_FORMAT_UNIT:                 // 0x04 - Mandatory
      case SBC_CMD_MODE_SELECT_6:               // 0x15 - Optional
      case SBC_CMD_SEND_DIAGNOSTIC:             // 0x1D - 
      case SBC_CMD_READ_LONG:                   // 0x23 - Optional
      case SBC_CMD_SYNCHRONIZE_CACHE:           // 0x35 - Optional
      case SBC_CMD_WRITE_BUFFER:                // 0x3B - Optional
      case SBC_CMD_RESERVE_10:                  // 0x56 - Mandatory
      case SBC_CMD_RELEASE_10:                  // 0x57 - Mandatory - see chapter 7.16 - SPC 2
      default:
      // Command not supported
      Sbc_send_failed();
      Sbc_build_sense(SBC_SENSE_KEY_ILLEGAL_REQUEST, SBC_ASC_INVALID_COMMAND_OPERATION_CODE, 0x00);
      return FALSE;
      break;
   }
   return TRUE;
}


Bool sbc_request_sense (void)
{
   U8  allocation_length, i;
   U8  request_sens_output[18];                             // the maximum size of request is 17

   allocation_length = g_scsi_command[4];                   // Allocation length
   if( allocation_length > 18 )
   {
      allocation_length = 18;
   }
   // Initialize the request sense data
   request_sens_output[0] = SBC_RESPONSE_CODE_SENSE;        // 70h
   request_sens_output[1] = 0x00;                           // Obsolete
   request_sens_output[2] = g_scsi_sense.key;

   request_sens_output[3] = 0x00;                           // For direct access media, Information field
   request_sens_output[4] = 0x00;                           // give the unsigned logical block
   request_sens_output[5] = 0x00;                           // address associated with the sense key
   request_sens_output[6] = 0x00;

   request_sens_output[7] = SBC_ADDITIONAL_SENSE_LENGTH;    // UFI device shall not adjust the Additional sense length to reflect truncation
   request_sens_output[8] = SBC_COMMAND_SPECIFIC_INFORMATION_3;
   request_sens_output[9] = SBC_COMMAND_SPECIFIC_INFORMATION_2;
   request_sens_output[10] = SBC_COMMAND_SPECIFIC_INFORMATION_1;
   request_sens_output[11] = SBC_COMMAND_SPECIFIC_INFORMATION_0;

   request_sens_output[12] = g_scsi_sense.asc;
   request_sens_output[13] = g_scsi_sense.ascq;

   request_sens_output[14] = SBC_FIELD_REPLACEABLE_UNIT_CODE;
   request_sens_output[15] = SBC_SENSE_KEY_SPECIFIC_2;
   request_sens_output[16] = SBC_SENSE_KEY_SPECIFIC_1;
   request_sens_output[17] = SBC_SENSE_KEY_SPECIFIC_0;

   // Send the request data
   for( i=0 ; i<allocation_length ; i++ )
   {
       Usb_write_byte( request_sens_output[i] );
   }
   Sbc_valid_write_usb( allocation_length );

   sbc_lun_status_is_good();
   return TRUE;
}


Bool sbc_inquiry (void)
{
   U8 allocation_length, i;

#ifdef __GNUC__
   PGM_VOID_P ptr;
#else
   U8 code *ptr;
#endif

   if( (0 != (g_scsi_command[1] & 0x03) )       // CMDT and EPVD bits are 0
   ||  (0 !=  g_scsi_command[2]         ) )     // PAGE or OPERATION CODE fields = 0x00?
   {  
      // (CMDT=EVPD <> 0) or (PAGE CODE <> 0x00)
      // No standard inquiry asked
      sbc_lun_status_is_cdb_field();
      return FALSE;
   }

   // Manage the standard inquiry command
   // Check the size of inquiry data
   allocation_length = g_scsi_command[4];
   if (allocation_length > SBC_MAX_INQUIRY_DATA)
   {
      allocation_length = SBC_MAX_INQUIRY_DATA;
   }

   // send first inquiry data (0 to 8)
   ptr = (code U8*) &sbc_std_inquiry_data;

   for ( i=0 ; ((i != 36) && (allocation_length > i)); i++)
   {
      if( 8 == i )
      {  // send vendor id (8 to 16)
           ptr = (code U8 *) &g_sbc_vendor_id;
      }
      if( 16 == i )
      {  // send product id (16 to 32)
         ptr = (code U8 *) &g_sbc_product_id;
      }
      if( 32 == i )
      {  // send revision id (32 to 36)
         ptr = (code U8 *) &g_sbc_revision_id;
      }
#ifndef __GNUC__
      Usb_write_byte((U8)(*ptr++));
#else    // AVRGCC does not support point to PGM space
      Usb_write_byte(pgm_read_byte_near((unsigned int)ptr++));
#endif

   }
   Sbc_valid_write_usb(i);
   sbc_lun_status_is_good();
   return TRUE;      
}


Bool sbc_test_unit_ready(void)
{
   switch ( mem_test_unit_ready(usb_LUN) )
   {
      case CTRL_GOOD :
      sbc_lun_status_is_good();
      break;

      case CTRL_NO_PRESENT :
      sbc_lun_status_is_not_present();
      break;

      case CTRL_BUSY :
      sbc_lun_status_is_busy_or_change();
      break;

      case CTRL_FAIL :
      default :
      sbc_lun_status_is_fail();
      break;
   }
   return TRUE;
}


Bool sbc_read_capacity (void)
{
   U32 mem_size_nb_sector;

   switch ( mem_read_capacity( usb_LUN, &mem_size_nb_sector ) )
   {
      case CTRL_GOOD :
      Usb_write_byte(MSB0(mem_size_nb_sector));    // return nb block
      Usb_write_byte(MSB1(mem_size_nb_sector));
      Usb_write_byte(MSB2(mem_size_nb_sector));
      Usb_write_byte(MSB3(mem_size_nb_sector));
      Usb_write_byte( 0               );           // return block size (= 512B)
      Usb_write_byte( 0               );
      Usb_write_byte( (U8)(512 >> 8)  );
      Usb_write_byte( (U8)(512 & 0xFF));

      Sbc_valid_write_usb(SBC_READ_CAPACITY_LENGTH);
      sbc_lun_status_is_good();
      return TRUE;
      break;

      case CTRL_NO_PRESENT :
      sbc_lun_status_is_not_present();
      break;

      case CTRL_BUSY :
      sbc_lun_status_is_busy_or_change();
      break;

      case CTRL_FAIL :
      default :
      sbc_lun_status_is_fail();
      break;
   }
   return FALSE;
}


Bool sbc_read_10 (void)
{
   U32   mass_addr;                       // rd or wr block address
   U16   mass_size;                       // rd or write nb of blocks

   MSB0(mass_addr) = g_scsi_command[2];   // read address
   MSB1(mass_addr) = g_scsi_command[3];
   MSB2(mass_addr) = g_scsi_command[4];
   MSB3(mass_addr) = g_scsi_command[5];

   MSB(mass_size) = g_scsi_command[7];    // read size
   LSB(mass_size) = g_scsi_command[8];
   
   if( Is_usb_ms_data_direction_out() )
   {
      sbc_lun_status_is_cdb_field();
      return FALSE;
   }
   if( 0 == g_scsi_data_remaining )
   {
      if( mass_size == (g_scsi_data_remaining/512) )
      {
         sbc_lun_status_is_good();
      }else{
         sbc_lun_status_is_cdb_field();
      }
      return TRUE;
   }

   switch ( memory_2_usb( usb_LUN , mass_addr,  g_scsi_data_remaining/512 ) )
   {
      case CTRL_GOOD :
      if( mass_size == (g_scsi_data_remaining/512) )
      {
         sbc_lun_status_is_good();
      }else{
         sbc_lun_status_is_cdb_field();
      }
      g_scsi_data_remaining = 0;
      break;

      case CTRL_NO_PRESENT :
      sbc_lun_status_is_not_present();
      return FALSE;
      break;

      case CTRL_BUSY :
      sbc_lun_status_is_busy_or_change();
      return FALSE;
      break;

      case CTRL_FAIL :
      default :
      sbc_lun_status_is_fail();
      return FALSE;
      break;
   }
   return TRUE;
}


Bool sbc_write_10 (void)
{
   U32   mass_addr;                       // rd or wr block address
   U16   mass_size;                       // rd or write nb of blocks

   MSB0(mass_addr) = g_scsi_command[2];   // read address
   MSB1(mass_addr) = g_scsi_command[3];
   MSB2(mass_addr) = g_scsi_command[4];
   MSB3(mass_addr) = g_scsi_command[5];

   MSB(mass_size) = g_scsi_command[7];    // read size
   LSB(mass_size) = g_scsi_command[8];
   
   if( Is_usb_ms_data_direction_in() )
   {
      sbc_lun_status_is_cdb_field();
      return FALSE;
   }

   if( 0 == g_scsi_data_remaining )
   {
      if( mass_size == (g_scsi_data_remaining/512) )
      {
         sbc_lun_status_is_good();
      }else{
         sbc_lun_status_is_cdb_field();
      }
      return TRUE;
   }
   
   if( TRUE == mem_wr_protect( usb_LUN ) )
   {
      sbc_lun_status_is_protected();
      return FALSE;
   }

   switch (usb_2_memory( usb_LUN , mass_addr, g_scsi_data_remaining/512 ))
   {
      case CTRL_GOOD :
      if( mass_size == (g_scsi_data_remaining/512) )
      {
         sbc_lun_status_is_good();
      }else{
         sbc_lun_status_is_cdb_field();
      }
      g_scsi_data_remaining = 0;
      break;

      case CTRL_NO_PRESENT :
      sbc_lun_status_is_not_present();
      return FALSE;
      break;

      case CTRL_BUSY :
      sbc_lun_status_is_busy_or_change();
      return FALSE;
      break;

      case CTRL_FAIL :
      default :
      sbc_lun_status_is_fail();
      return FALSE;
      break;
   }
   return TRUE;
}


Bool sbc_mode_sense( Bool b_sense_10 )
{
   U8 allocation_length;

   if( b_sense_10 )
      allocation_length = g_scsi_command[8];
   else
      allocation_length = g_scsi_command[4];

   // switch for page code
   switch ( g_scsi_command[2] & SBC_MSK_PAGE_CODE )
   {
      case SBC_PAGE_CODE_INFORMATIONAL_EXCEPTIONS:
      sbc_header_mode_sense( b_sense_10 , SBC_MODE_DATA_LENGTH_INFORMATIONAL_EXCEPTIONS );
      send_informational_exceptions_page();
      Sbc_valid_write_usb(SBC_MODE_DATA_LENGTH_INFORMATIONAL_EXCEPTIONS + 1);
      break;

      case SBC_PAGE_CODE_READ_WRITE_ERROR_RECOVERY:
      sbc_header_mode_sense( b_sense_10 , SBC_MODE_DATA_LENGTH_READ_WRITE_ERROR_RECOVERY );
      send_read_write_error_recovery_page(allocation_length);
      Sbc_valid_write_usb(SBC_MODE_DATA_LENGTH_READ_WRITE_ERROR_RECOVERY + 1);
      break;

      case SBC_PAGE_CODE_ALL:
      if( b_sense_10 ) {
         sbc_header_mode_sense( b_sense_10 , (allocation_length < (SBC_MODE_DATA_LENGTH_CODE_ALL+2))? (allocation_length-2) : SBC_MODE_DATA_LENGTH_CODE_ALL );
      }else{
         sbc_header_mode_sense( b_sense_10 , (allocation_length < (SBC_MODE_DATA_LENGTH_CODE_ALL+1))? (allocation_length-1) : SBC_MODE_DATA_LENGTH_CODE_ALL );
      }
      if( b_sense_10 )
      {
         if (allocation_length == 8)
         {
            Sbc_valid_write_usb(8);
            break;
         }
      }
      else
      {
         if (allocation_length == 4)
         {
            Sbc_valid_write_usb(4);
            break;
         }
      }
      // send page by ascending order code
      send_read_write_error_recovery_page(allocation_length);  // 12 bytes
      if (allocation_length > 12)
      {
         send_informational_exceptions_page();                 // 12 bytes
         Sbc_valid_write_usb(SBC_MODE_DATA_LENGTH_CODE_ALL + 1);
      }
      else
      {
         Sbc_valid_write_usb(allocation_length);
      }
      break;

      default:
      sbc_lun_status_is_cdb_field();
      return FALSE;
      break;
   }
   sbc_lun_status_is_good();
   return TRUE;
}


void sbc_header_mode_sense( Bool b_sense_10 , U8 u8_data_length )
{
   // Send Data length
   if( b_sense_10 )
   {
      Usb_write_byte(0);
   }
   Usb_write_byte( u8_data_length );

   // Send device type
   Usb_write_byte(SBC_MEDIUM_TYPE);

   // Write protect status
   if (mem_wr_protect( usb_LUN ))
   {
      Usb_write_byte(SBC_DEV_SPEC_PARAM_WR_PROTECT);  // Device is write protected
   }
   else
   {
      Usb_write_byte(SBC_DEV_SPEC_PARAM_WR_ENABLE);   // Device is write enabled
   }

   if( b_sense_10 )
   {  // Reserved
      Usb_write_byte(0);
      Usb_write_byte(0);
   }

   // Send Block descriptor length
   if( b_sense_10 )
   {
      Usb_write_byte(0);
   }
   Usb_write_byte(SBC_BLOCK_DESCRIPTOR_LENGTH);
}


void send_informational_exceptions_page (void)
{
   Usb_write_byte(SBC_PAGE_CODE_INFORMATIONAL_EXCEPTIONS);     // Page Code: Informational exceptions control page
                                                               // See chapter 8.3.8 on SPC-2 specification
   Usb_write_byte(SBC_PAGE_LENGTH_INFORMATIONAL_EXCEPTIONS);   // Page Length
   Usb_write_byte(0x00);                                       // ..., Test bit = 0, ...
   Usb_write_byte(SBC_MRIE);                                   // MRIE = 0x05
   Usb_write_byte(0x00);                                       // Interval Timer (MSB)
   Usb_write_byte(0x00);
   Usb_write_byte(0x00);
   Usb_write_byte(0x00);                                       // Interval Timer (LSB)
   Usb_write_byte(0x00);                                       // Report Count (MSB)
   Usb_write_byte(0x00);
   Usb_write_byte(0x00);
   Usb_write_byte(0x01);                                       // Report Count (LSB)
}


void send_read_write_error_recovery_page (U8 length)
{
   Usb_write_byte(SBC_PAGE_CODE_READ_WRITE_ERROR_RECOVERY);

   Usb_write_byte(SBC_PAGE_LENGTH_READ_WRITE_ERROR_RECOVERY);   // Page Length
   Usb_write_byte(0x80);
   Usb_write_byte(SBC_READ_RETRY_COUNT);
   Usb_write_byte(SBC_CORRECTION_SPAN);
   Usb_write_byte(SBC_HEAD_OFFSET_COUNT);
   Usb_write_byte(SBC_DATA_STROBE_OFFSET);
   Usb_write_byte(0x00);   // Reserved

   if (length > 12)
   {
      Usb_write_byte(SBC_WRITE_RETRY_COUNT);
      Usb_write_byte(0x00);
      Usb_write_byte(SBC_RECOVERY_LIMIT_MSB);
      Usb_write_byte(SBC_RECOVERY_LIMIT_LSB);
   }
}

Bool sbc_prevent_allow_medium_removal(void)
{
   sbc_lun_status_is_good();
   return TRUE;
}


void sbc_lun_status_is_good(void)
{
   Sbc_send_good();
   Sbc_build_sense(SBC_SENSE_KEY_NO_SENSE, SBC_ASC_NO_ADDITIONAL_SENSE_INFORMATION, 0x00);
}

void sbc_lun_status_is_not_present(void)
{
   Sbc_send_failed();
   Sbc_build_sense(SBC_SENSE_KEY_NOT_READY, SBC_ASC_MEDIUM_NOT_PRESENT, 0x00);
}

void sbc_lun_status_is_busy_or_change(void)
{
   Sbc_send_failed();
   Sbc_build_sense(SBC_SENSE_KEY_UNIT_ATTENTION, SBC_ASC_NOT_READY_TO_READY_CHANGE, 0x00 );
}

void sbc_lun_status_is_fail(void)
{
   Sbc_send_failed();
   Sbc_build_sense(SBC_SENSE_KEY_HARDWARE_ERROR, SBC_ASC_NO_ADDITIONAL_SENSE_INFORMATION, 0x00);
}

void sbc_lun_status_is_protected(void)
{
   Sbc_send_failed();
   Sbc_build_sense(SBC_SENSE_KEY_DATA_PROTECT, SBC_ASC_WRITE_PROTECTED, 0x00);
}

void sbc_lun_status_is_cdb_field(void)
{
   Sbc_send_failed();
   Sbc_build_sense(SBC_SENSE_KEY_ILLEGAL_REQUEST, SBC_ASC_INVALID_FIELD_IN_CDB, 0x00);
}

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