Хост-контроллер SD / MMC (SMHC): список регистров

  Unused

  RESERVED1

Reserved

  IDMAC_ERR_STA

Error Bits
Indicates the type of error that caused a Bus Error. Valid only with Fatal Bus
Error bit (IDSTS[2]) set. This field does not generate an interrupt.
001: Host Abort received during transmission
010: Host Abort received during reception
Others: Reserved
The bit is read-only.

  ABN_INT_SUM_AIS

Abnormal Interrupt Summary
Logical OR of the following:
IDSTS[2]: Fatal Bus Interrupt
IDSTS[4]: Descriptor Unavailable bit Interrupt
IDSTS[5]: Card Error Summary Interrupt
Only unmasked bits affect this bit.
This is a sticky bit and must be cleared each time a corresponding bit that
causes AIS to be set is cleared. Writing a 1 clears this bit.

  NOR_INT_SUM_NIS

Normal Interrupt Summary
Logical OR of the following:
IDSTS[0]: Transmit Interrupt
IDSTS[1]: Receive Interrupt
Only unmasked bits affect this bit.
This is a sticky bit and must be cleared each time a corresponding bit that
causes NIS to be set is cleared. Writing a 1 clears this bit.

  Unused

  ERR_FLAG_SUM

Card Error Summary
Indicates the status of the transaction to/from the card; also present in RINT-STS.
Indicates the logical OR of the following bits:
EBE: End Bit Error
RTO: Response Timeout/Boot ACK Timeout
RCRC: Response CRC
SBE: Start Bit Error
DRTO: Data Read Timeout/BDS timeout
DCRC: Data CRC for Receive
RE: Response Error
Writing a 1 clears this bit.

  DES_UNAVL_INT

Descriptor Unavailable Interrupt
This bit is set when the descriptor is unavailable due to OWN bit = 0
(DES0[31] =0).
Writing a 1 clears this bit.

  Unused

  FATAL_BERR_INT

Fatal Bus Error Interrupt
Indicates that a Bus Error occurred (IDSTS[12:10]). When this bit is set, the
DMA disables all its bus accesses.
Writing a 1 clears this bit.

  RX_INT

Receive Interrupt
Indicates the completion of data reception for a descriptor.
Writing a 1 clears this bit.

  TX_INT

Transmit Interrupt
Indicates that data transmission is finished for a descriptor.
Writing a 1 clears this bit.

Команда U-Boot для чтения регистра

Bit fields structure

typedef union  smhc_idst
{
  struct
  {
   unsigned tx_int : 1;
   unsigned rx_int : 1;
   unsigned fatal_berr_int : 1;
   unsigned unused0 : 1;
   unsigned des_unavl_int : 1;
   unsigned err_flag_sum : 1;
   unsigned unused1 : 2;
   unsigned nor_int_sum_nis : 1;
   unsigned abn_int_sum_ais : 1;
   unsigned idmac_err_sta : 3;
   unsigned reserved1 : 4;
   unsigned unused2 : 15;
  } b;
   unsigned long w;
} SMHC_IDST