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Diffstat (limited to 'board/xes/xpedite537x/ddr.c')
| -rw-r--r-- | board/xes/xpedite537x/ddr.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/board/xes/xpedite537x/ddr.c b/board/xes/xpedite537x/ddr.c new file mode 100644 index 0000000..4d3f255 --- /dev/null +++ b/board/xes/xpedite537x/ddr.c @@ -0,0 +1,270 @@ +/* + * Copyright 2008 Extreme Engineering Solutions, Inc. + * Copyright 2008 Freescale Semiconductor, Inc. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <i2c.h> + +#include <asm/fsl_ddr_sdram.h> +#include <asm/fsl_ddr_dimm_params.h> + +static void get_spd(ddr2_spd_eeprom_t *spd, unsigned char i2c_address) +{ + i2c_read(i2c_address, SPD_EEPROM_OFFSET, 2, (uchar *)spd, + sizeof(ddr2_spd_eeprom_t)); +} + +unsigned int fsl_ddr_get_mem_data_rate(void) +{ + return get_ddr_freq(0); +} + +void fsl_ddr_get_spd(ddr2_spd_eeprom_t *ctrl_dimms_spd, + unsigned int ctrl_num) +{ + unsigned int i; + unsigned int i2c_address = 0; + + for (i = 0; i < CONFIG_DIMM_SLOTS_PER_CTLR; i++) { + if (ctrl_num == 0) + i2c_address = SPD_EEPROM_ADDRESS1; + if (ctrl_num == 1) + i2c_address = SPD_EEPROM_ADDRESS2; + get_spd(&(ctrl_dimms_spd[i]), i2c_address); + } +} + +/* + * There are four board-specific SDRAM timing parameters which must be + * calculated based on the particular PCB artwork. These are: + * 1.) CPO (Read Capture Delay) + * - TIMING_CFG_2 register + * Source: Calculation based on board trace lengths and + * chip-specific internal delays. + * 2.) WR_DATA_DELAY (Write Command to Data Strobe Delay) + * - TIMING_CFG_2 register + * Source: Calculation based on board trace lengths. + * Unless clock and DQ lanes are very different + * lengths (>2"), this should be set to the nominal value + * of 1/2 clock delay. + * 3.) CLK_ADJUST (Clock and Addr/Cmd alignment control) + * - DDR_SDRAM_CLK_CNTL register + * Source: Signal Integrity Simulations + * 4.) 2T Timing on Addr/Ctl + * - TIMING_CFG_2 register + * Source: Signal Integrity Simulations + * Usually only needed with heavy load/very high speed (>DDR2-800) + * + * ====== XPedite5370 DDR2-600 read delay calculations ====== + * + * See Freescale's App Note AN2583 as refrence. This document also + * contains the chip-specific delays for 8548E, 8572, etc. + * + * For MPC8572E + * Minimum chip delay (Ch 0): 1.372ns + * Maximum chip delay (Ch 0): 2.914ns + * Minimum chip delay (Ch 1): 1.220ns + * Maximum chip delay (Ch 1): 2.595ns + * + * CLK adjust = 5 (from simulations) = 5/8* 3.33ns = 2080ps + * + * Minimum delay calc (Ch 0): + * clock prop - dram skew + min dqs prop delay + clk_adjust + min chip dly + * 2.3" * 180 - 400ps + 1.9" * 180 + 2080ps + 1372ps + * = 3808ps + * = 3.808ns + * + * Maximum delay calc (Ch 0): + * clock prop + dram skew + max dqs prop delay + clk_adjust + max chip dly + * 2.3" * 180 + 400ps + 2.4" * 180 + 2080ps + 2914ps + * = 6240ps + * = 6.240ns + * + * Minimum delay calc (Ch 1): + * clock prop - dram skew + min dqs prop delay + clk_adjust + min chip dly + * 1.46" * 180- 400ps + 0.7" * 180 + 2080ps + 1220ps + * = 3288ps + * = 3.288ns + * + * Maximum delay calc (Ch 1): + * clock prop + dram skew + max dqs prop delay + clk_adjust + min chip dly + * 1.46" * 180+ 400ps + 1.1" * 180 + 2080ps + 2595ps + * = 5536ps + * = 5.536ns + * + * Ch.0: 3.808ns to 6.240ns additional delay needed (pick 5ns as target) + * This is 1.5 clock cycles, pick CPO = READ_LAT + 3/2 (0x8) + * Ch.1: 3.288ns to 5.536ns additional delay needed (pick 4.4ns as target) + * This is 1.32 clock cycles, pick CPO = READ_LAT + 5/4 (0x7) + * + * + * ====== XPedite5370 DDR2-800 read delay calculations ====== + * + * See Freescale's App Note AN2583 as refrence. This document also + * contains the chip-specific delays for 8548E, 8572, etc. + * + * For MPC8572E + * Minimum chip delay (Ch 0): 1.372ns + * Maximum chip delay (Ch 0): 2.914ns + * Minimum chip delay (Ch 1): 1.220ns + * Maximum chip delay (Ch 1): 2.595ns + * + * CLK adjust = 5 (from simulations) = 5/8* 2.5ns = 1563ps + * + * Minimum delay calc (Ch 0): + * clock prop - dram skew + min dqs prop delay + clk_adjust + min chip dly + * 2.3" * 180 - 350ps + 1.9" * 180 + 1563ps + 1372ps + * = 3341ps + * = 3.341ns + * + * Maximum delay calc (Ch 0): + * clock prop + dram skew + max dqs prop delay + clk_adjust + max chip dly + * 2.3" * 180 + 350ps + 2.4" * 180 + 1563ps + 2914ps + * = 5673ps + * = 5.673ns + * + * Minimum delay calc (Ch 1): + * clock prop - dram skew + min dqs prop delay + clk_adjust + min chip dly + * 1.46" * 180- 350ps + 0.7" * 180 + 1563ps + 1220ps + * = 2822ps + * = 2.822ns + * + * Maximum delay calc (Ch 1): + * clock prop + dram skew + max dqs prop delay + clk_adjust + min chip dly + * 1.46" * 180+ 350ps + 1.1" * 180 + 1563ps + 2595ps + * = 4968ps + * = 4.968ns + * + * Ch.0: 3.341ns to 5.673ns additional delay needed (pick 4.5ns as target) + * This is 1.8 clock cycles, pick CPO = READ_LAT + 7/4 (0x9) + * Ch.1: 2.822ns to 4.968ns additional delay needed (pick 3.9ns as target) + * This is 1.56 clock cycles, pick CPO = READ_LAT + 3/2 (0x8) + * + * Write latency (WR_DATA_DELAY) is calculated by doing the following: + * + * The DDR SDRAM specification requires DQS be received no sooner than + * 75% of an SDRAM clock period—and no later than 125% of a clock + * period—from the capturing clock edge of the command/address at the + * SDRAM. + * + * Based on the above tracelengths, the following are calculated: + * Ch. 0 8572 to DRAM propagation (DQ lanes) : 1.9" * 180 = 0.342ns + * Ch. 0 8572 to DRAM propagation (CLKs) : 2.3" * 180 = 0.414ns + * Ch. 1 8572 to DRAM propagation (DQ lanes) : 0.7" * 180 = 0.126ns + * Ch. 1 8572 to DRAM propagation (CLKs ) : 1.47" * 180 = 0.264ns + * + * Difference in arrival time CLK vs. DQS: + * Ch. 0 0.072ns + * Ch. 1 0.138ns + * + * Both of these values are much less than 25% of the clock + * period at DDR2-600 or DDR2-800, so no additional delay is needed over + * the 1/2 cycle which normally aligns the first DQS transition + * exactly WL (CAS latency minus one cycle) after the CAS strobe. + * See Figure 9-53 in MPC8572E manual: "1/2 delay" in Freescale's + * terminology corresponds to exactly one clock period delay after + * the CAS strobe. (due to the fact that the "delay" is referenced + * from the *falling* edge of the CLK, just after the rising edge + * which the CAS strobe is latched on. + */ + +typedef struct board_memctl_options { + uint16_t datarate_mhz_low; + uint16_t datarate_mhz_high; + uint8_t clk_adjust; + uint8_t cpo_override; + uint8_t write_data_delay; +} board_memctl_options_t; + +static struct board_memctl_options bopts_ctrl[][2] = { + { + /* Controller 0 */ + { + /* DDR2 600/667 */ + .datarate_mhz_low = 500, + .datarate_mhz_high = 750, + .clk_adjust = 5, + .cpo_override = 8, + .write_data_delay = 2, + }, + { + /* DDR2 800 */ + .datarate_mhz_low = 750, + .datarate_mhz_high = 850, + .clk_adjust = 5, + .cpo_override = 9, + .write_data_delay = 2, + }, + }, + { + /* Controller 1 */ + { + /* DDR2 600/667 */ + .datarate_mhz_low = 500, + .datarate_mhz_high = 750, + .clk_adjust = 5, + .cpo_override = 7, + .write_data_delay = 2, + }, + { + /* DDR2 800 */ + .datarate_mhz_low = 750, + .datarate_mhz_high = 850, + .clk_adjust = 5, + .cpo_override = 8, + .write_data_delay = 2, + }, + }, +}; + +void fsl_ddr_board_options(memctl_options_t *popts, + dimm_params_t *pdimm, + unsigned int ctrl_num) +{ + struct board_memctl_options *bopts = bopts_ctrl[ctrl_num]; + sys_info_t sysinfo; + int i; + unsigned int datarate; + + get_sys_info(&sysinfo); + datarate = sysinfo.freqDDRBus / 1000 / 1000; + + for (i = 0; i < ARRAY_SIZE(bopts_ctrl[ctrl_num]); i++) { + if ((bopts[i].datarate_mhz_low <= datarate) && + (bopts[i].datarate_mhz_high >= datarate)) { + debug("controller %d:\n", ctrl_num); + debug(" clk_adjust = %d\n", bopts[i].clk_adjust); + debug(" cpo = %d\n", bopts[i].cpo_override); + debug(" write_data_delay = %d\n", + bopts[i].write_data_delay); + popts->clk_adjust = bopts[i].clk_adjust; + popts->cpo_override = bopts[i].cpo_override; + popts->write_data_delay = bopts[i].write_data_delay; + } + } + + /* + * Factors to consider for half-strength driver enable: + * - number of DIMMs installed + */ + popts->half_strength_driver_enable = 0; +} |