SPRZ575 March   2024 AM67 , AM67A , TDA4AEN-Q1 , TDA4VEN-Q1

 

  1.   1
  2. 1Modules Affected
  3. 2Nomenclature, Package Symbolization, and Revision Identification
    1. 2.1 Device and Development-Support Tool Nomenclature
    2. 2.2 Devices Supported
    3. 2.3 Package Symbolization and Revision Identification
  4. 3Silicon Revision 1.0 Usage Notes and Advisories
    1. 3.1 Silicon Revision 1.0 Usage Notes
      1.      i2134
    2. 3.2 Silicon Revision 1.0 Advisories
      1.      i2049
      2.      i2062
      3.      i2097
      4.      i2120
      5.      i2137
      6.      i2189
      7.      i2190
      8.      i2196
      9.      i2199
      10.      i2208
      11.      i2242
      12.      i2243
      13.      i2249
      14.      i2253
      15.      i2278
      16.      i2279
      17.      i2310
      18.      i2311
      19.      i2312
      20.      i2326
      21.      i2351
      22.      i2362
      23.      i2366
      24.      i2372
      25.      i2383
      26.      i2399
      27.      i2401
      28.      i2407
      29.      i2409
      30.      i2410
  5.   Trademarks
  6. 4Revision History

i2362

10-100M SGMII: Marvell PHY does not ignore the preamble byte resulting in link failure

Details:

The CPSW SGMII module outputs up to 5 bytes of 0x50 preamble data when in 10/100 mode and there is an odd number of clocks between packets. All bytes should be 0x55. In 1000Mbps mode, which does not have the issue, there are seven 0x55's in the preamble previous to the SFD. In 100Mbps mode there are 70 bytes in the preamble before the SFD (because the data is replicated 10 times from 1000Mbps mode). The first five bytes of the seventy can be 0x50 when the issue occurs. This issue has been undetected until now due to testing only with the PHYs that allow the preamble to be eroded and don't care about the actual data in the first number of bytes However, this issue was recently detected with a Marvel PHY (88Q1111 or similar) that looks at the preamble data and makes packet keep/discard decisions based on preamble data of 0x50.

Workaround(s):

The workaround options are:

1. Use 1000M mode which does not have the issue.

OR

2. Use a TI PHY (DP83869 or similar) or any other PHY which can erode/ignore the preamble data in 10/100/1000M mode.