software/liblitedram: Improve find_cmd_delay to favor higher number of valid modules and centered scan.

Also add an optional debug #define to look at cmd/clk centering scans:

        __   _ __      _  __
       / /  (_) /____ | |/_/
      / /__/ / __/ -_)>  <
     /____/_/\__/\__/_/|_|
   Build your hardware, easily!

 (c) Copyright 2012-2020 Enjoy-Digital
 (c) Copyright 2007-2015 M-Labs

 BIOS built on Mar 12 2021 14:06:20
 BIOS CRC passed (116682af)

 Migen git sha1: 7014bdc
 LiteX git sha1: edcc0f88

--=============== SoC ==================--
CPU:		VexRiscv @ 125MHz
BUS:		WISHBONE 32-bit @ 4GiB
CSR:		32-bit data
ROM:		64KiB
SRAM:		8KiB
L2:		8KiB
SDRAM:		1048576KiB 64-bit @ 1000MT/s (CL-7 CWL-6)

--========== Initialization ============--
Initializing SDRAM @0x40000000...
Switching SDRAM to software control.
Write leveling:
  tCK/4 taps: 6
  Cmd/Clk scan (0-12)
  |Cmd/Clk delay: 0
  m0: |11000000000000011111111111| delay: 15
  m1: |00000000000000111111111111| delay: 14
  m2: |11110000000000000111111111| delay: 17
  m3: |11110000000000000011111111| delay: 18
  m4: |11111111110000000000000111| delay: -
  m5: |11111111110000000000000111| delay: -
  m6: |11111111111000000000000001| delay: -
  m7: |11111111111000000000000011| delay: -
Delay mean: 22, ideal: 13
Cmd/Clk delay: 1
  m0: |11100000000000001111111111| delay: 16
  m1: |10000000000000011111111111| delay: 15
  m2: |11111000000000000011111111| delay: 18
  m3: |11111000000000000001111111| delay: 19
  m4: |11111111111000000000000011| delay: -
  m5: |11111111111000000000000011| delay: -
  m6: |11111111111100000000000000| delay: -
  m7: |11111111111100000000000001| delay: -
Delay mean: 23, ideal: 13
Cmd/Clk delay: 2
  m0: |11110000000000000111111111| delay: 17
  m1: |11000000000000001111111111| delay: 16
  m2: |11111100000000000001111111| delay: -
  m3: |11111100000000000000111111| delay: -
  m4: |11111111111100000000000001| delay: -
  m5: |11111111111100000000000001| delay: -
  m6: |11111111111110000000000000| delay: -
  m7: |11111111111110000000000000| delay: -
Delay mean: 22, ideal: 13
Cmd/Clk delay: 3
  m0: |11111000000000000011111111| delay: 18
  m1: |11100000000000000111111111| delay: 17
  m2: |11111110000000000000111111| delay: -
  m3: |11111110000000000000011111| delay: -
  m4: |11111111111110000000000000| delay: -
  m5: |11111111111110000000000000| delay: -
  m6: |01111111111111000000000000| delay: 01
  m7: |01111111111111000000000000| delay: 01
Delay mean: 15, ideal: 13
Cmd/Clk delay: 4
  m0: |11111100000000000001111111| delay: -
  m1: |11110000000000000011111111| delay: 18
  m2: |11111111000000000000011111| delay: -
  m3: |11111111000000000000001111| delay: -
  m4: |11111111111111000000000000| delay: -
  m5: |11111111111111000000000000| delay: -
  m6: |00111111111111100000000000| delay: 02
  m7: |00111111111111100000000000| delay: 02
Delay mean: 13, ideal: 13
Cmd/Clk delay: 5
  m0: |11111110000000000000111111| delay: -
  m1: |11111000000000000001111111| delay: 19
  m2: |11111111100000000000001111| delay: -
  m3: |11111111100000000000000111| delay: -
  m4: |01111111111111100000000000| delay: 01
  m5: |01111111111111100000000000| delay: 01
  m6: |00011111111111110000000000| delay: 03
  m7: |00011111111111110000000000| delay: 03
Delay mean: 11, ideal: 13
Cmd/Clk delay: 6
  m0: |11111111000000000000011111| delay: -
  m1: |11111100000000000000111111| delay: -
  m2: |11111111110000000000000111| delay: -
  m3: |11111111110000000000000011| delay: -
  m4: |00111111111111110000000000| delay: 02
  m5: |00011111111111110000000000| delay: 03
  m6: |00001111111111111000000000| delay: 04
  m7: |00001111111111111000000000| delay: 04
Delay mean: 9, ideal: 13
Cmd/Clk delay: 7
  m0: |11111111100000000000001111| delay: -
  m1: |11111110000000000000011111| delay: -
  m2: |11111111111000000000000011| delay: -
  m3: |11111111111000000000000001| delay: -
  m4: |00011111111111111000000000| delay: 03
  m5: |00001111111111111000000000| delay: 04
  m6: |00000111111111111100000000| delay: 05
  m7: |00000111111111111100000000| delay: 05
Delay mean: 10, ideal: 13
Cmd/Clk delay: 8
  m0: |11111111110000000000000111| delay: -
  m1: |11111111000000000000001111| delay: -
  m2: |11111111111100000000000001| delay: -
  m3: |11111111111100000000000000| delay: -
  m4: |00001111111111111100000000| delay: 04
  m5: |00000111111111111100000000| delay: 05
  m6: |00000011111111111110000000| delay: 06
  m7: |00000011111111111110000000| delay: 06
Delay mean: 11, ideal: 13
Cmd/Clk delay: 9
  m0: |11111111111000000000000011| delay: -
  m1: |11111111100000000000000111| delay: -
  m2: |11111111111110000000000000| delay: -
  m3: |11111111111110000000000000| delay: -
  m4: |00000111111111111110000000| delay: 05
  m5: |00000011111111111110000000| delay: 06
  m6: |00000001111111111111000000| delay: 07
  m7: |00000001111111111111000000| delay: 07
Delay mean: 12, ideal: 13
Cmd/Clk delay: 10
  m0: |11111111111100000000000011| delay: -
  m1: |11111111110000000000000011| delay: -
  m2: |01111111111111000000000000| delay: 01
  m3: |01111111111111000000000000| delay: 01
  m4: |00000011111111111111000000| delay: 06
  m5: |00000001111111111111000000| delay: 07
  m6: |00000000111111111111100000| delay: 08
  m7: |00000000111111111111100000| delay: 08
Delay mean: 11, ideal: 13
Cmd/Clk delay: 11
  m0: |11111111111110000000000001| delay: -
  m1: |11111111111000000000000001| delay: -
  m2: |00111111111111100000000000| delay: 02
  m3: |00111111111111100000000000| delay: 02
  m4: |00000001111111111111100000| delay: 07
  m5: |00000000111111111111100000| delay: 08
  m6: |00000000011111111111110000| delay: 09
  m7: |00000000011111111111110000| delay: 09
Delay mean: 12, ideal: 13
| best: 11
  Setting Cmd/Clk delay to 11 taps.
  Data scan:
  m0: |11111111111110000000000001| delay: -
  m1: |11111111111000000000000001| delay: -
  m2: |00111111111111100000000000| delay: 02
  m3: |00111111111111100000000000| delay: 02
  m4: |00000001111111111111100000| delay: 07
  m5: |00000000111111111111100000| delay: 08
  m6: |00000000011111111111110000| delay: 09
  m7: |00000000011111111111110000| delay: 09
Write latency calibration:
m0:6 m1:6 m2:6 m3:6 m4:6 m5:6 m6:6 m7:6
Read leveling:
  m0, b0: |00000000000000000000000000000000| delays: -
  m0, b1: |00000000000000000000000000000000| delays: -
  m0, b2: |00000000000000000000000000000000| delays: -
  m0, b3: |11111111100000000000000000000000| delays: 04+-04
  m0, b4: |00000000000001111111110000000000| delays: 17+-04
  m0, b5: |00000000000000000000000000111111| delays: 29+-03
  m0, b6: |00000000000000000000000000000000| delays: -
  m0, b7: |00000000000000000000000000000000| delays: -
  best: m0, b03 delays: 04+-04
  m1, b0: |00000000000000000000000000000000| delays: -
  m1, b1: |00000000000000000000000000000000| delays: -
  m1, b2: |00000000000000000000000000000000| delays: -
  m1, b3: |11111111000000000000000000000000| delays: 04+-04
  m1, b4: |00000000000011111111100000000000| delays: 16+-04
  m1, b5: |00000000000000000000000000111111| delays: 29+-03
  m1, b6: |00000000000000000000000000000000| delays: -
  m1, b7: |00000000000000000000000000000000| delays: -
  best: m1, b04 delays: 16+-04
  m2, b0: |00000000000000000000000000000000| delays: -
  m2, b1: |00000000000000000000000000000000| delays: -
  m2, b2: |00000000000000000000000000000000| delays: -
  m2, b3: |11111110000000000000000000000000| delays: 03+-03
  m2, b4: |00000000000111111111000000000000| delays: 15+-04
  m2, b5: |00000000000000000000000011111111| delays: 28+-04
  m2, b6: |00000000000000000000000000000000| delays: -
  m2, b7: |00000000000000000000000000000000| delays: -
  best: m2, b04 delays: 15+-04
  m3, b0: |00000000000000000000000000000000| delays: -
  m3, b1: |00000000000000000000000000000000| delays: -
  m3, b2: |00000000000000000000000000000000| delays: -
  m3, b3: |11111110000000000000000000000000| delays: 03+-03
  m3, b4: |00000000001111111110000000000000| delays: 14+-04
  m3, b5: |00000000000000000000000011111111| delays: 28+-04
  m3, b6: |00000000000000000000000000000000| delays: -
  m3, b7: |00000000000000000000000000000000| delays: -
  best: m3, b04 delays: 14+-04
  m4, b0: |00000000000000000000000000000000| delays: -
  m4, b1: |00000000000000000000000000000000| delays: -
  m4, b2: |00000000000000000000000000000000| delays: -
  m4, b3: |10000000000000000000000000000000| delays: -
  m4, b4: |00001111111110000000000000000000| delays: 08+-04
  m4, b5: |00000000000000000111111111000000| delays: 22+-05
  m4, b6: |00000000000000000000000000000001| delays: 31+-00
  m4, b7: |00000000000000000000000000000000| delays: -
  best: m4, b04 delays: 08+-04
  m5, b0: |00000000000000000000000000000000| delays: -
  m5, b1: |00000000000000000000000000000000| delays: -
  m5, b2: |00000000000000000000000000000000| delays: -
  m5, b3: |00000000000000000000000000000000| delays: -
  m5, b4: |00001111111110000000000000000000| delays: 08+-04
  m5, b5: |00000000000000000011111111000000| delays: 22+-04
  m5, b6: |00000000000000000000000000000001| delays: 31+-00
  m5, b7: |00000000000000000000000000000000| delays: -
  best: m5, b04 delays: 08+-04
  m6, b0: |00000000000000000000000000000000| delays: -
  m6, b1: |00000000000000000000000000000000| delays: -
  m6, b2: |00000000000000000000000000000000| delays: -
  m6, b3: |00000000000000000000000000000000| delays: -
  m6, b4: |00111111110000000000000000000000| delays: 06+-04
  m6, b5: |00000000000000111111111000000000| delays: 18+-04
  m6, b6: |00000000000000000000000000001111| delays: 30+-02
  m6, b7: |00000000000000000000000000000000| delays: -
  best: m6, b05 delays: 19+-04
  m7, b0: |00000000000000000000000000000000| delays: -
  m7, b1: |00000000000000000000000000000000| delays: -
  m7, b2: |00000000000000000000000000000000| delays: -
  m7, b3: |00000000000000000000000000000000| delays: -
  m7, b4: |01111111111100000000000000000000| delays: 06+-05
  m7, b5: |00000000000000011111111110000000| delays: 20+-05
  m7, b6: |00000000000000000000000000001111| delays: 30+-02
  m7, b7: |00000000000000000000000000000000| delays: -
  best: m7, b04 delays: 06+-05
Switching SDRAM to hardware control.
Memtest at 0x40000000 (2MiB)...
  Write: 0x40000000-0x40200000 2MiB
   Read: 0x40000000-0x40200000 2MiB
Memtest OK
Memspeed at 0x40000000 (2MiB)...
  Write speed: 40MiB/s
   Read speed: 33MiB/s

--============== Boot ==================--
Booting from serial...
Press Q or ESC to abort boot completely.
sL5DdSMmkekro
Timeout
No boot medium found

--============= Console ================--
This commit is contained in:
Florent Kermarrec 2021-03-12 12:37:35 +01:00
parent 3cbdc567ff
commit 1e9606f3fb
1 changed files with 35 additions and 16 deletions

View File

@ -25,6 +25,7 @@
#include "sdram.h"
//#define SDRAM_TEST_DISABLE
//#define SDRAM_WRITE_LEVELING_CMD_DELAY_DEBUG
#ifdef CSR_SDRAM_BASE
@ -503,12 +504,15 @@ static int sdram_write_leveling_scan(int *delays, int loops, int show)
return ok;
}
static void sdram_write_leveling_find_cmd_delay(unsigned int *best_error, int *best_cdly,
static void sdram_write_leveling_find_cmd_delay(unsigned int *best_error, unsigned int *best_count, int *best_cdly,
int cdly_start, int cdly_stop, int cdly_step)
{
int cdly;
int cdly_actual = 0;
int delays[SDRAM_PHY_MODULES];
#ifndef SDRAM_WRITE_LEVELING_CMD_DELAY_DEBUG
int ok;
#endif
/* Scan through the range */
ddrphy_cdly_rst_write(1);
@ -522,28 +526,42 @@ static void sdram_write_leveling_find_cmd_delay(unsigned int *best_error, int *b
}
/* Write level using this delay */
if (sdram_write_leveling_scan(delays, 8, 0)) {
/* Use the mean of delays for error calulation */
int delay_mean = 0;
for (int i=0; i < SDRAM_PHY_MODULES; ++i) {
delay_mean += delays[i];
#ifdef SDRAM_WRITE_LEVELING_CMD_DELAY_DEBUG
printf("Cmd/Clk delay: %d\n", cdly);
sdram_write_leveling_scan(delays, 8, 1);
#else
ok = sdram_write_leveling_scan(delays, 8, 0);
#endif
/* Use the mean of delays for error calulation */
int delay_mean = 0;
int delay_count = 0;
for (int i=0; i < SDRAM_PHY_MODULES; ++i) {
if (delays[i] != -1) {
delay_mean += delays[i] + ddrphy_half_sys8x_taps_read();
delay_count += 1;
}
delay_mean /= SDRAM_PHY_MODULES;
}
if (delay_count != 0)
delay_mean /= delay_count;
/* We want it to be at the start */
int ideal_delay = 0;
int error = ideal_delay - delay_mean;
if (error < 0)
error *= -1;
/* We want the higher number of valid modules and delay to be centered */
int ideal_delay = (SDRAM_PHY_DELAYS - ddrphy_half_sys8x_taps_read())/2;
int error = ideal_delay - delay_mean;
if (error < 0)
error *= -1;
if (delay_count >= *best_count) {
*best_count = delay_count;
if (error < *best_error) {
*best_cdly = cdly;
*best_error = error;
}
printf("1");
} else {
printf("0");
}
#ifdef SDRAM_WRITE_LEVELING_CMD_DELAY_DEBUG
printf("Delay mean: %d, ideal: %d\n", delay_mean, ideal_delay);
#else
printf("%d", ok);
#endif
}
}
@ -551,6 +569,7 @@ int sdram_write_leveling(void)
{
int delays[SDRAM_PHY_MODULES];
unsigned int best_error = ~0u;
unsigned int best_count = 0;
int best_cdly = -1;
int cdly_range_start;
int cdly_range_end;
@ -578,7 +597,7 @@ int sdram_write_leveling(void)
cdly_range_step = 1;
while (cdly_range_step > 0) {
printf(" |");
sdram_write_leveling_find_cmd_delay(&best_error, &best_cdly,
sdram_write_leveling_find_cmd_delay(&best_error, &best_count, &best_cdly,
cdly_range_start, cdly_range_end, cdly_range_step);
/* Small optimization - stop if we have zero error */