diff options
| author | Huayang Duan <huayang.duan@mediatek.com> | 2019-11-20 13:51:47 +0800 |
|---|---|---|
| committer | Patrick Georgi <pgeorgi@google.com> | 2019-12-20 17:57:03 +0000 |
| commit | 6ee5559d6a3c1ba452a53db58ec6b41d629d92b2 (patch) | |
| tree | b59d973bc534adfd4fad17301e0e2d2222a9d7ac /src | |
| parent | 6de7ecb585e705beab32e7464d364f2284ccae54 (diff) | |
soc/mediatek/mt8183: Use DDR clock to compute Tx delay cell
The delay cell result should use DDR clock PLL rate for computation,
and should not be divided by 2.
This helps to improve DRAM stability.
BUG=b:80501386,b:142358843
BRANCH=kukui
TEST=Boots correctly on Kukui
Change-Id: Idf5cce206e248bb327f9a7d27c4f364ef1c68aa1
Signed-off-by: Huayang Duan <huayang.duan@mediatek.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36990
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Diffstat (limited to 'src')
| -rw-r--r-- | src/soc/mediatek/mt8183/dramc_pi_calibration_api.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/src/soc/mediatek/mt8183/dramc_pi_calibration_api.c b/src/soc/mediatek/mt8183/dramc_pi_calibration_api.c index 8c17d84df0..0ec0193664 100644 --- a/src/soc/mediatek/mt8183/dramc_pi_calibration_api.c +++ b/src/soc/mediatek/mt8183/dramc_pi_calibration_api.c @@ -1588,18 +1588,24 @@ static void dramc_set_tx_best_dly(u8 chn, u8 rank, bool bypass_tx, struct per_byte_dly center_dly[DQS_NUMBER]; u16 tune_diff, dq_delay_cell[DQ_DATA_WIDTH]; + + /* + * The clock rate is usually (frequency / 2 - delta), where the delta + * is introduced to avoid interference from RF peripherals like + * modem, WiFi, and Bluetooth. + */ switch (freq_group) { case LP4X_DDR1600: - clock_rate = 800; + clock_rate = 796; break; case LP4X_DDR2400: - clock_rate = 1200; + clock_rate = 1196; break; case LP4X_DDR3200: - clock_rate = 1600; + clock_rate = 1596; break; case LP4X_DDR3600: - clock_rate = 1866; + clock_rate = 1792; break; default: die("Invalid DDR frequency group %u\n", freq_group); @@ -1612,7 +1618,7 @@ static void dramc_set_tx_best_dly(u8 chn, u8 rank, bool bypass_tx, use_delay_cell = 0; if (fast_calib && bypass_tx) { - dramc_dbg("bypass TX\n"); + dramc_dbg("bypass TX, clock_rate: %d\n", clock_rate); for (u8 byte = 0; byte < DQS_NUMBER; byte++) { center_dly[byte].min_center = params->tx_center_min[chn][rank][byte]; center_dly[byte].max_center = params->tx_center_max[chn][rank][byte]; @@ -1645,8 +1651,10 @@ static void dramc_set_tx_best_dly(u8 chn, u8 rank, bool bypass_tx, tune_diff = vref_dly[index].win_center - center_dly[byte].min_center; dq_delay_cell[index] = ((tune_diff * 100000000) / - (clock_rate / 2 * 64)) / dly_cell_unit; + (clock_rate * 64)) / dly_cell_unit; byte_dly_cell[byte] |= (dq_delay_cell[index] << (bit * 4)); + dramc_show("u1DelayCellOfst[%d]=%d cells (%d PI)\n", + index, dq_delay_cell[index], tune_diff); } } } |