diff --git a/litex/soc/software/liblitedram/sdram.c b/litex/soc/software/liblitedram/sdram.c
index 1e65d9601..3ced36b94 100644
--- a/litex/soc/software/liblitedram/sdram.c
+++ b/litex/soc/software/liblitedram/sdram.c
@@ -6,6 +6,7 @@
 // This file is Copyright (c) 2018 Jean-François Nguyen <jf@lambdaconcept.fr>
 // This file is Copyright (c) 2018 Sergiusz Bazanski <q3k@q3k.org>
 // This file is Copyright (c) 2018 Tim 'mithro' Ansell <me@mith.ro>
+// This file is Copyright (c) 2021 Antmicro <www.antmicro.com>
 // License: BSD
 
 #include <generated/csr.h>
@@ -57,7 +58,7 @@ __attribute__((unused)) void cdelay(int i)
 #define MEMTEST_DATA_SIZE (2*1024*1024)
 #endif
 
-#define DFII_PIX_DATA_BYTES SDRAM_PHY_DATABITS*SDRAM_PHY_XDR/8
+#define DFII_PIX_DATA_BYTES SDRAM_PHY_DFI_DATABITS/8
 
 int sdram_get_databits(void) {
 	return SDRAM_PHY_DATABITS;
@@ -299,7 +300,7 @@ static void print_scan_errors(unsigned int errors) {
 #endif
 }
 
-#define READ_CHECK_TEST_PATTERN_MAX_ERRORS (SDRAM_PHY_PHASES*2*32)
+#define READ_CHECK_TEST_PATTERN_MAX_ERRORS (8*SDRAM_PHY_PHASES*SDRAM_PHY_XDR)
 
 static unsigned int sdram_write_read_check_test_pattern(int module, unsigned int seed) {
 	int p, i;
@@ -346,8 +347,12 @@ static unsigned int sdram_write_read_check_test_pattern(int module, unsigned int
 		/* Read back test pattern */
 		csr_rd_buf_uint8(sdram_dfii_pix_rddata_addr(p), tst, DFII_PIX_DATA_BYTES);
 		/* Verify bytes matching current 'module' */
-		errors += popcount(prs[p][	SDRAM_PHY_MODULES-1-module] ^ tst[	SDRAM_PHY_MODULES-1-module]);
-		errors += popcount(prs[p][2*SDRAM_PHY_MODULES-1-module] ^ tst[2*SDRAM_PHY_MODULES-1-module]);
+		for (int i = 0; i < DFII_PIX_DATA_BYTES; ++i) {
+			int j = p * DFII_PIX_DATA_BYTES + i;
+			if (j % SDRAM_PHY_MODULES == SDRAM_PHY_MODULES-1-module) {
+				errors += popcount(prs[p][i] ^ tst[i]);
+			}
+		}
 	}
 
 #ifdef SDRAM_PHY_ECP5DDRPHY