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bios/sdram: changes to ease manual read window selection

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This commit is contained in:
Florent Kermarrec 2018-08-18 13:45:22 +02:00
parent a760322fbd
commit 9547938527
1 changed files with 18 additions and 8 deletions
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26
litex/soc/software/bios/sdram.c
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@ -731,6 +731,7 @@ int sdrlevel(void)
int delay[DFII_PIX_DATA_SIZE/2]; int delay[DFII_PIX_DATA_SIZE/2];
int high_skew[DFII_PIX_DATA_SIZE/2]; int high_skew[DFII_PIX_DATA_SIZE/2];
int i, j; int i, j;
int bitslip;
for(i=0; i<DFII_PIX_DATA_SIZE/2; i++) { for(i=0; i<DFII_PIX_DATA_SIZE/2; i++) {
ddrphy_dly_sel_write(1<<i); ddrphy_dly_sel_write(1<<i);
@ -748,20 +749,29 @@ int sdrlevel(void)
if(!write_level(delay, high_skew)) if(!write_level(delay, high_skew))
return 0; return 0;
#endif #endif
/* check for optimal read leveling window */ /* check possible read windows (based on bitslip) */
for(i=0; i<ERR_DDRPHY_BITSLIP; i++) { for(bitslip=0; bitslip<ERR_DDRPHY_BITSLIP; bitslip++) {
/* scan */ /* scan */
if (read_level_scan(1)) if (read_level_scan(1))
break; break;
if (i == ERR_DDRPHY_BITSLIP-1) if (bitslip == ERR_DDRPHY_BITSLIP-1)
return 0; return 0;
/* increment bitslip */ /* increment bitslip */
for(j=0; j<DFII_PIX_DATA_SIZE/2; j++) for(i=0; i<DFII_PIX_DATA_SIZE/2; i++)
read_bitslip_inc(j); read_bitslip_inc(i);
} }
/* show bitslip and scan */
printf("Read bitslip: %d\n", i); /* select read window (bitslip)*/
read_level_scan(0); printf("Read bitslip: %d\n", bitslip);
for(i=0; i<DFII_PIX_DATA_SIZE/2; i++) {
ddrphy_dly_sel_write(1<<i);
ddrphy_rdly_dq_bitslip_rst_write(1);
for (j=0; j<bitslip; j++)
read_bitslip_inc(i);
}
/* scan selected read window */
read_level_scan(0);
read_level(); read_level();
return 1; return 1;