Map_EmacConfigSet() fails to set {DGF} bit 5 in (EMACDMAOPMODE) REG58:0xC18

Genatco

Adding one more bit set [5] (Drop giant frames) to existing bit set commands but EMACDMAOPMODE REG58 is not obeying Map_EMACConfigSet().

Does making RX Watchdog set enable over ride the giant frame set bit [5] in REG58?

Possibly some undocumented vital information around these registers behaviors?

 /* Set MAC configuration options in REG-58:0xC18 (EMACDMAOPMODE).
  * Reference: hw_emach.h, emac.h */

    MAP_EMACConfigSet(EMAC0_BASE, (EMAC_CONFIG_FULL_DUPLEX |
                                   EMAC_CONFIG_CHECKSUM_OFFLOAD |
                                   EMAC_CONFIG_7BYTE_PREAMBLE |
                                   EMAC_CONFIG_IF_GAP_96BITS |
                                   EMAC_CONFIG_USE_MACADDR0 |
                                   EMAC_CONFIG_SA_FROM_DESCRIPTOR |
                                   EMAC_CONFIG_BO_LIMIT_1024 |
                                   EMAC_DMAOPMODE_DGF), // Drop Giant Frames
    		            /* Configure the DMA engine to operate on the first frame
    		             * sending updates of descriptor status words on completion. */
                       (EMAC_MODE_RX_STORE_FORWARD |         //set RSF[21], (Reset) clears
                        EMAC_MODE_TX_STORE_FORWARD), 2048);  //set TSF[25], (Reset) clears
                         // TTC/RTC Ignored (TX/RX(SF)[25,21] set
                         // >2048-RX Giant frames watchdog timer WDIS.

over 10 years ago

0 Amit Ashara over 10 years ago

TI__Guru**** 244400 points

Hello BP101

Does a manual write of the register bit in the configuration allow it to remain set? Need to check if there is a function call which causes the bit to get cleared

Regards
Amit

0 Genatco over 10 years ago in reply to Amit Ashara

Guru 55923 points

Hi Amit,

Think what we are seeing in this behavior is not related to SW. Rather HW architecture registers appear to deny DGF based on other register settings. The datasheet text does list any constraint over DGF[5]. Suspect text leaves out information or other an errata exists in the complex DMAIM/OPMODE.

0 Genatco over 10 years ago in reply to Genatco

Guru 55923 points

Opps - the register 58 Dword was put in the wrong place in EMACConfigSet():

The proper location:

(EMAC_MODE_RX_STORE_FORWARD | 
 EMAC_MODE_TX_STORE_FORWARD | 
          EMAC_DMAOPMODE_DGF), 2048);

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Map_EmacConfigSet() fails to set {DGF} bit 5 in (EMACDMAOPMODE) REG58:0xC18