SPRZ530B april   2022  – june 2023 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-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.      i2063
      4.      i2064
      5.      i2065
      6.      i2079
      7.      i2091
      8.      i2097
      9.      i2103
      10.      i2120
      11.      i2134
      12.      i2137
      13.      i2146
      14.      i2157
      15.      i2159
      16.      i2160
      17.      i2161
      18.      i2163
      19.      i2166
      20.      i2177
      21.      i2189
      22.      i2190
      23.      i2196
      24.      i2197
      25.      i2205
      26.      i2215
      27.      i2216
      28.      i2219
      29.      i2232
      30.      i2234
      31.      i2235
      32.      i2237
      33.      i2242
      34.      i2243
      35.      i2244
      36.      i2245
      37.      i2249
      38.      i2253
      39.      i2271
      40.      i2272
      41.      i2278
      42.      i2279
      43.      i2283
      44.      i2307
      45.      i2308
      46.      i2310
      47.      i2311
      48.      i2312
      49.      i2313
      50.      i2316
      51.      i2320
      52.      i2326
      53.      i2329
      54.      i2351
      55.      i2362
      56.      i2366
      57.      i2371
      58.      i2372
      59.      i2378
      60.      i2381
      61.      i2383
  5.   Trademarks
  6.   Revision History

i2243

PCIe: Timing requirement for disabling output refclk during L1.2 substate is not met

Details

PCIe base specification requires Refclk to reach idle electrical state within 100ns of CLKREQ# deassertion when entering L1.2 substate (please refer TL1O_REFCLK_OFF parameter).

This timing requirement cannot be met when sourcing Refclk from the device since hardware does not automatically gate Refclk. Refclk gating has to be performed by software by writing to PHY_EN_REFCLK field in SERDES_RST register.

As a result, Refclk cannot be gated in L1.2 substate. Generally, allowing Refclk to run in L1.2 substate is not expected to cause any functional issues. However, if gating Refclk within 100ns is required by the system, L1.2 substate cannot be supported.

Workaround

Use an external Refclk generator to supply the PCIe reference clock