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liblitedram: Fix LFSR 

LFSR only returns 1 random bit per lfsr() call,
so we should concatenate 8 consecutive calls to obtain 1 random byte

Signed-off-by: Maciej Dudek <mdudek@antmicro.com>
This commit is contained in:
Maciej Dudek 2023-01-25 11:35:20 +01:00 committed by Michal Sieron
parent 48f547885a
commit cd89b62ff6
1 changed files with 8 additions and 3 deletions
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11
litex/soc/software/liblitedram/sdram.c
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@ -301,9 +301,10 @@ static void print_scan_errors(unsigned int errors) {
#define MODULE_BITMASK ((1<<SDRAM_PHY_DQ_DQS_RATIO)-1)
static unsigned int sdram_write_read_check_test_pattern(int module, unsigned int seed) {
int p, i;
int p, i, bit;
unsigned int errors;
unsigned int prv;
unsigned char value;
unsigned char tst[DFII_PIX_DATA_BYTES];
unsigned char prs[SDRAM_PHY_PHASES][DFII_PIX_DATA_BYTES];
@ -311,8 +312,12 @@ static unsigned int sdram_write_read_check_test_pattern(int module, unsigned int
prv = seed;
for(p=0;p<SDRAM_PHY_PHASES;p++) {
for(i=0;i<DFII_PIX_DATA_BYTES;i++) {
prv = lfsr(32, prv);
prs[p][i] = prv;
value = 0;
for (bit=0;bit<8;bit++) {
prv = lfsr(32, prv);
value |= (prv&1) << bit;
}
prs[p][i] = value;
}
}