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authorXie Xiaobo <r63061@freescale.com>2007-02-14 18:27:17 +0800
committerKim Phillips <kim.phillips@freescale.com>2007-03-02 11:05:54 -0600
commitd61853cf2472e0b8bcbd131461a93d1c49ff0c1f (patch)
tree993c4b0fda27f49928163533fddd09c26da97840 /cpu/mpc83xx
parentb110f40bd180c6b560276589beedf753e97c46ce (diff)
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mpc83xx: Add DDR2 controller fixed/SPD Init for MPC83xx
The code supply fixed and SPD initialization for MPC83xx DDR2 Controller. it pass DDR/DDR2 compliance tests. Signed-off-by: Xie Xiaobo <X.Xie@freescale.com>
Diffstat (limited to 'cpu/mpc83xx')
-rw-r--r--cpu/mpc83xx/spd_sdram.c384
1 files changed, 323 insertions, 61 deletions
diff --git a/cpu/mpc83xx/spd_sdram.c b/cpu/mpc83xx/spd_sdram.c
index 108328a..d9b8753 100644
--- a/cpu/mpc83xx/spd_sdram.c
+++ b/cpu/mpc83xx/spd_sdram.c
@@ -106,16 +106,29 @@ long int spd_sdram()
volatile ddr83xx_t *ddr = &immap->ddr;
volatile law83xx_t *ecm = &immap->sysconf.ddrlaw[0];
spd_eeprom_t spd;
+ unsigned int n_ranks;
+ unsigned int odt_rd_cfg, odt_wr_cfg;
+ unsigned char twr_clk, twtr_clk;
+ unsigned char sdram_type;
unsigned int memsize;
unsigned int law_size;
unsigned char caslat, caslat_ctrl;
+ unsigned int trfc, trfc_clk, trfc_low, trfc_high;
+ unsigned int trcd_clk, trtp_clk;
+ unsigned char cke_min_clk;
+ unsigned char add_lat, wr_lat;
+ unsigned char wr_data_delay;
+ unsigned char four_act;
+ unsigned char cpo;
unsigned char burstlen;
+ unsigned char odt_cfg, mode_odt_enable;
unsigned int max_bus_clk;
unsigned int max_data_rate, effective_data_rate;
unsigned int ddrc_clk;
unsigned int refresh_clk;
- unsigned sdram_cfg;
+ unsigned int sdram_cfg;
unsigned int ddrc_ecc_enable;
+ unsigned int pvr = get_pvr();
/* Read SPD parameters with I2C */
CFG_READ_SPD(SPD_EEPROM_ADDRESS, 0, 1, (uchar *) & spd, sizeof (spd));
@@ -123,19 +136,25 @@ long int spd_sdram()
spd_debug(&spd);
#endif
/* Check the memory type */
- if (spd.mem_type != SPD_MEMTYPE_DDR) {
+ if (spd.mem_type != SPD_MEMTYPE_DDR && spd.mem_type != SPD_MEMTYPE_DDR2) {
printf("DDR: Module mem type is %02X\n", spd.mem_type);
return 0;
}
/* Check the number of physical bank */
- if (spd.nrows > 2) {
- printf("DDR: The number of physical bank is %02X\n", spd.nrows);
+ if (spd.mem_type == SPD_MEMTYPE_DDR) {
+ n_ranks = spd.nrows;
+ } else {
+ n_ranks = (spd.nrows & 0x7) + 1;
+ }
+
+ if (n_ranks > 2) {
+ printf("DDR: The number of physical bank is %02X\n", n_ranks);
return 0;
}
/* Check if the number of row of the module is in the range of DDRC */
- if (spd.nrow_addr < 12 || spd.nrow_addr > 14) {
+ if (spd.nrow_addr < 12 || spd.nrow_addr > 15) {
printf("DDR: Row number is out of range of DDRC, row=%02X\n",
spd.nrow_addr);
return 0;
@@ -147,20 +166,43 @@ long int spd_sdram()
spd.ncol_addr);
return 0;
}
+
+#ifdef CFG_DDRCDR_VALUE
+ /*
+ * Adjust DDR II IO voltage biasing. It just makes it work.
+ */
+ if(spd.mem_type == SPD_MEMTYPE_DDR2) {
+ immap->sysconf.ddrcdr = CFG_DDRCDR_VALUE;
+ }
+#endif
+
+ /*
+ * ODT configuration recommendation from DDR Controller Chapter.
+ */
+ odt_rd_cfg = 0; /* Never assert ODT */
+ odt_wr_cfg = 0; /* Never assert ODT */
+ if (spd.mem_type == SPD_MEMTYPE_DDR2) {
+ odt_wr_cfg = 1; /* Assert ODT on writes to CSn */
+ }
+
/* Setup DDR chip select register */
#ifdef CFG_83XX_DDR_USES_CS0
ddr->csbnds[0].csbnds = (banksize(spd.row_dens) >> 24) - 1;
ddr->cs_config[0] = ( 1 << 31
+ | (odt_rd_cfg << 20)
+ | (odt_wr_cfg << 16)
| (spd.nrow_addr - 12) << 8
| (spd.ncol_addr - 8) );
debug("\n");
debug("cs0_bnds = 0x%08x\n",ddr->csbnds[0].csbnds);
debug("cs0_config = 0x%08x\n",ddr->cs_config[0]);
- if (spd.nrows == 2) {
+ if (n_ranks == 2) {
ddr->csbnds[1].csbnds = ( (banksize(spd.row_dens) >> 8)
| ((banksize(spd.row_dens) >> 23) - 1) );
ddr->cs_config[1] = ( 1<<31
+ | (odt_rd_cfg << 20)
+ | (odt_wr_cfg << 16)
| (spd.nrow_addr-12) << 8
| (spd.ncol_addr-8) );
debug("cs1_bnds = 0x%08x\n",ddr->csbnds[1].csbnds);
@@ -170,16 +212,20 @@ long int spd_sdram()
#else
ddr->csbnds[2].csbnds = (banksize(spd.row_dens) >> 24) - 1;
ddr->cs_config[2] = ( 1 << 31
+ | (odt_rd_cfg << 20)
+ | (odt_wr_cfg << 16)
| (spd.nrow_addr - 12) << 8
| (spd.ncol_addr - 8) );
debug("\n");
debug("cs2_bnds = 0x%08x\n",ddr->csbnds[2].csbnds);
debug("cs2_config = 0x%08x\n",ddr->cs_config[2]);
- if (spd.nrows == 2) {
+ if (n_ranks == 2) {
ddr->csbnds[3].csbnds = ( (banksize(spd.row_dens) >> 8)
| ((banksize(spd.row_dens) >> 23) - 1) );
ddr->cs_config[3] = ( 1<<31
+ | (odt_rd_cfg << 20)
+ | (odt_wr_cfg << 16)
| (spd.nrow_addr-12) << 8
| (spd.ncol_addr-8) );
debug("cs3_bnds = 0x%08x\n",ddr->csbnds[3].csbnds);
@@ -187,15 +233,10 @@ long int spd_sdram()
}
#endif
- if (spd.mem_type != 0x07) {
- puts("No DDR module found!\n");
- return 0;
- }
-
/*
* Figure out memory size in Megabytes.
*/
- memsize = spd.nrows * banksize(spd.row_dens) / 0x100000;
+ memsize = n_ranks * banksize(spd.row_dens) / 0x100000;
/*
* First supported LAW size is 16M, at LAWAR_SIZE_16M == 23.
@@ -215,24 +256,32 @@ long int spd_sdram()
* in the spd.cas_lat field. Translate it to a DDR
* controller field value:
*
- * CAS Lat DDR I Ctrl
- * Clocks SPD Bit Value
- * -------+--------+---------
- * 1.0 0 001
- * 1.5 1 010
- * 2.0 2 011
- * 2.5 3 100
- * 3.0 4 101
- * 3.5 5 110
- * 4.0 6 111
+ * CAS Lat DDR I DDR II Ctrl
+ * Clocks SPD Bit SPD Bit Value
+ * ------- ------- ------- -----
+ * 1.0 0 0001
+ * 1.5 1 0010
+ * 2.0 2 2 0011
+ * 2.5 3 0100
+ * 3.0 4 3 0101
+ * 3.5 5 0110
+ * 4.0 6 4 0111
+ * 4.5 1000
+ * 5.0 5 1001
*/
caslat = __ilog2(spd.cas_lat);
-
- if (caslat > 6 ) {
- printf("DDR: Invalid SPD CAS Latency, caslat=%02X\n",
- spd.cas_lat);
+ if ((spd.mem_type == SPD_MEMTYPE_DDR)
+ && (caslat > 6)) {
+ printf("DDR I: Invalid SPD CAS Latency: 0x%x.\n", spd.cas_lat);
+ return 0;
+ } else if (spd.mem_type == SPD_MEMTYPE_DDR2
+ && (caslat < 2 || caslat > 5)) {
+ printf("DDR II: Invalid SPD CAS Latency: 0x%x.\n",
+ spd.cas_lat);
return 0;
}
+ debug("DDR: caslat SPD bit is %d\n", caslat);
+
max_bus_clk = 1000 *10 / (((spd.clk_cycle & 0xF0) >> 4) * 10
+ (spd.clk_cycle & 0x0f));
max_data_rate = max_bus_clk * 2;
@@ -240,10 +289,11 @@ long int spd_sdram()
debug("DDR:Module maximum data rate is: %dMhz\n", max_data_rate);
ddrc_clk = gd->ddr_clk / 1000000;
+ effective_data_rate = 0;
- if (max_data_rate >= 390) { /* it is DDR 400 */
- if (ddrc_clk <= 410 && ddrc_clk > 350) {
- /* DDR controller clk at 350~410 */
+ if (max_data_rate >= 390 && max_data_rate < 460) { /* it is DDR 400 */
+ if (ddrc_clk <= 460 && ddrc_clk > 350) {
+ /* DDR controller clk at 350~460 */
effective_data_rate = 400; /* 5ns */
caslat = caslat;
} else if (ddrc_clk <= 350 && ddrc_clk > 280) {
@@ -258,16 +308,16 @@ long int spd_sdram()
effective_data_rate = 266; /* 7.5ns */
if (spd.clk_cycle3 == 0x75)
caslat = caslat - 2;
- else if (spd.clk_cycle2 == 0x60)
+ else if (spd.clk_cycle2 == 0x75)
caslat = caslat - 1;
else
caslat = caslat;
} else if (ddrc_clk <= 230 && ddrc_clk > 90) {
/* DDR controller clk at 90~230 */
effective_data_rate = 200; /* 10ns */
- if (spd.clk_cycle3 == 0x75)
+ if (spd.clk_cycle3 == 0xa0)
caslat = caslat - 2;
- else if (spd.clk_cycle2 == 0x60)
+ else if (spd.clk_cycle2 == 0xa0)
caslat = caslat - 1;
else
caslat = caslat;
@@ -289,7 +339,7 @@ long int spd_sdram()
effective_data_rate = 200; /* 10ns */
if (spd.clk_cycle3 == 0xa0)
caslat = caslat - 2;
- else if (spd.clk_cycle2 == 0x75)
+ else if (spd.clk_cycle2 == 0xa0)
caslat = caslat - 1;
else
caslat = caslat;
@@ -330,41 +380,197 @@ long int spd_sdram()
* Errata DDR6 work around: input enable 2 cycles earlier.
* including MPC834x Rev1.0/1.1 and MPC8360 Rev1.1/1.2.
*/
- if (caslat == 2)
- ddr->debug_reg = 0x201c0000; /* CL=2 */
- else if (caslat == 3)
- ddr->debug_reg = 0x202c0000; /* CL=2.5 */
- else if (caslat == 4)
- ddr->debug_reg = 0x202c0000; /* CL=3.0 */
+ if(PVR_MAJ(pvr) <= 1 && spd.mem_type == SPD_MEMTYPE_DDR){
+ if (caslat == 2)
+ ddr->debug_reg = 0x201c0000; /* CL=2 */
+ else if (caslat == 3)
+ ddr->debug_reg = 0x202c0000; /* CL=2.5 */
+ else if (caslat == 4)
+ ddr->debug_reg = 0x202c0000; /* CL=3.0 */
- __asm__ __volatile__ ("sync");
+ __asm__ __volatile__ ("sync");
- debug("Errata DDR6 (debug_reg=0x%08x)\n", ddr->debug_reg);
+ debug("Errata DDR6 (debug_reg=0x%08x)\n", ddr->debug_reg);
+ }
/*
- * note: caslat must also be programmed into ddr->sdram_mode
- * register.
- *
- * note: WRREC(Twr) and WRTORD(Twtr) are not in SPD,
- * use conservative value here.
+ * Convert caslat clocks to DDR controller value.
+ * Force caslat_ctrl to be DDR Controller field-sized.
*/
- caslat_ctrl = (caslat + 1) & 0x07; /* see as above */
+ if (spd.mem_type == SPD_MEMTYPE_DDR) {
+ caslat_ctrl = (caslat + 1) & 0x07;
+ } else {
+ caslat_ctrl = (2 * caslat - 1) & 0x0f;
+ }
+
+ debug("DDR: effective data rate is %d MHz\n", effective_data_rate);
+ debug("DDR: caslat SPD bit is %d, controller field is 0x%x\n",
+ caslat, caslat_ctrl);
+
+ /*
+ * Timing Config 0.
+ * Avoid writing for DDR I.
+ */
+ if (spd.mem_type == SPD_MEMTYPE_DDR2) {
+ unsigned char taxpd_clk = 8; /* By the book. */
+ unsigned char tmrd_clk = 2; /* By the book. */
+ unsigned char act_pd_exit = 2; /* Empirical? */
+ unsigned char pre_pd_exit = 6; /* Empirical? */
+
+ ddr->timing_cfg_0 = (0
+ | ((act_pd_exit & 0x7) << 20) /* ACT_PD_EXIT */
+ | ((pre_pd_exit & 0x7) << 16) /* PRE_PD_EXIT */
+ | ((taxpd_clk & 0xf) << 8) /* ODT_PD_EXIT */
+ | ((tmrd_clk & 0xf) << 0) /* MRS_CYC */
+ );
+ debug("DDR: timing_cfg_0 = 0x%08x\n", ddr->timing_cfg_0);
+ }
+
+ /*
+ * For DDR I, WRREC(Twr) and WRTORD(Twtr) are not in SPD,
+ * use conservative value.
+ * For DDR II, they are bytes 36 and 37, in quarter nanos.
+ */
+
+ if (spd.mem_type == SPD_MEMTYPE_DDR) {
+ twr_clk = 3; /* Clocks */
+ twtr_clk = 1; /* Clocks */
+ } else {
+ twr_clk = picos_to_clk(spd.twr * 250);
+ twtr_clk = picos_to_clk(spd.twtr * 250);
+ }
+
+ /*
+ * Calculate Trfc, in picos.
+ * DDR I: Byte 42 straight up in ns.
+ * DDR II: Byte 40 and 42 swizzled some, in ns.
+ */
+ if (spd.mem_type == SPD_MEMTYPE_DDR) {
+ trfc = spd.trfc * 1000; /* up to ps */
+ } else {
+ unsigned int byte40_table_ps[8] = {
+ 0,
+ 250,
+ 330,
+ 500,
+ 660,
+ 750,
+ 0,
+ 0
+ };
+
+ trfc = (((spd.trctrfc_ext & 0x1) * 256) + spd.trfc) * 1000
+ + byte40_table_ps[(spd.trctrfc_ext >> 1) & 0x7];
+ }
+ trfc_clk = picos_to_clk(trfc);
+
+ /*
+ * Trcd, Byte 29, from quarter nanos to ps and clocks.
+ */
+ trcd_clk = picos_to_clk(spd.trcd * 250) & 0x7;
+
+ /*
+ * Convert trfc_clk to DDR controller fields. DDR I should
+ * fit in the REFREC field (16-19) of TIMING_CFG_1, but the
+ * 83xx controller has an extended REFREC field of three bits.
+ * The controller automatically adds 8 clocks to this value,
+ * so preadjust it down 8 first before splitting it up.
+ */
+ trfc_low = (trfc_clk - 8) & 0xf;
+ trfc_high = ((trfc_clk - 8) >> 4) & 0x3;
ddr->timing_cfg_1 =
- (((picos_to_clk(spd.trp * 250) & 0x07) << 28 ) |
- ((picos_to_clk(spd.tras * 1000) & 0x0f ) << 24 ) |
- ((picos_to_clk(spd.trcd * 250) & 0x07) << 20 ) |
- ((caslat_ctrl & 0x07) << 16 ) |
- (((picos_to_clk(spd.trfc * 1000) - 8) & 0x0f) << 12 ) |
- ( 0x300 ) |
- ((picos_to_clk(spd.trrd * 250) & 0x07) << 4) | 1);
+ (((picos_to_clk(spd.trp * 250) & 0x07) << 28 ) | /* PRETOACT */
+ ((picos_to_clk(spd.tras * 1000) & 0x0f ) << 24 ) | /* ACTTOPRE */
+ (trcd_clk << 20 ) | /* ACTTORW */
+ (caslat_ctrl << 16 ) | /* CASLAT */
+ (trfc_low << 12 ) | /* REFEC */
+ ((twr_clk & 0x07) << 8) | /* WRRREC */
+ ((picos_to_clk(spd.trrd * 250) & 0x07) << 4) | /* ACTTOACT */
+ ((twtr_clk & 0x07) << 0) /* WRTORD */
+ );
+
+ /*
+ * Additive Latency
+ * For DDR I, 0.
+ * For DDR II, with ODT enabled, use "a value" less than ACTTORW,
+ * which comes from Trcd, and also note that:
+ * add_lat + caslat must be >= 4
+ */
+ add_lat = 0;
+ if (spd.mem_type == SPD_MEMTYPE_DDR2
+ && (odt_wr_cfg || odt_rd_cfg)
+ && (caslat < 4)) {
+ add_lat = trcd_clk - 1;
+ if ((add_lat + caslat) < 4) {
+ add_lat = 0;
+ }
+ }
+
+ /*
+ * Write Data Delay
+ * Historically 0x2 == 4/8 clock delay.
+ * Empirically, 0x3 == 6/8 clock delay is suggested for DDR I 266.
+ */
+ wr_data_delay = 2;
+
+ /*
+ * Write Latency
+ * Read to Precharge
+ * Minimum CKE Pulse Width.
+ * Four Activate Window
+ */
+ if (spd.mem_type == SPD_MEMTYPE_DDR) {
+ /*
+ * This is a lie. It should really be 1, but if it is
+ * set to 1, bits overlap into the old controller's
+ * otherwise unused ACSM field. If we leave it 0, then
+ * the HW will magically treat it as 1 for DDR 1. Oh Yea.
+ */
+ wr_lat = 0;
+
+ trtp_clk = 2; /* By the book. */
+ cke_min_clk = 1; /* By the book. */
+ four_act = 1; /* By the book. */
+
+ } else {
+ wr_lat = caslat - 1;
+
+ /* Convert SPD value from quarter nanos to picos. */
+ trtp_clk = picos_to_clk(spd.trtp * 250);
- ddr->timing_cfg_2 = 0x00000800;
+ cke_min_clk = 3; /* By the book. */
+ four_act = picos_to_clk(37500); /* By the book. 1k pages? */
+ }
+
+ /*
+ * Empirically set ~MCAS-to-preamble override for DDR 2.
+ * Your milage will vary.
+ */
+ cpo = 0;
+ if (spd.mem_type == SPD_MEMTYPE_DDR2) {
+ if (effective_data_rate == 266 || effective_data_rate == 333) {
+ cpo = 0x7; /* READ_LAT + 5/4 */
+ } else if (effective_data_rate == 400) {
+ cpo = 0x9; /* READ_LAT + 7/4 */
+ } else {
+ /* Automatic calibration */
+ cpo = 0x1f;
+ }
+ }
+
+ ddr->timing_cfg_2 = (0
+ | ((add_lat & 0x7) << 28) /* ADD_LAT */
+ | ((cpo & 0x1f) << 23) /* CPO */
+ | ((wr_lat & 0x7) << 19) /* WR_LAT */
+ | ((trtp_clk & 0x7) << 13) /* RD_TO_PRE */
+ | ((wr_data_delay & 0x7) << 10) /* WR_DATA_DELAY */
+ | ((cke_min_clk & 0x7) << 6) /* CKE_PLS */
+ | ((four_act & 0x1f) << 0) /* FOUR_ACT */
+ );
debug("DDR:timing_cfg_1=0x%08x\n", ddr->timing_cfg_1);
debug("DDR:timing_cfg_2=0x%08x\n", ddr->timing_cfg_2);
- /* Setup init value, but not enable */
- ddr->sdram_cfg = 0x42000000;
/* Check DIMM data bus width */
if (spd.dataw_lsb == 0x20) {
@@ -384,7 +590,8 @@ long int spd_sdram()
/* Burst length is always 4 for 64 bit data bus, 8 for 32 bit data bus,
Burst type is sequential
*/
- switch (caslat) {
+ if (spd.mem_type == SPD_MEMTYPE_DDR) {
+ switch (caslat) {
case 1:
ddr->sdram_mode = 0x50 | burstlen; /* CL=1.5 */
break;
@@ -400,9 +607,36 @@ long int spd_sdram()
default:
printf("DDR:only CL 1.5, 2.0, 2.5, 3.0 is supported\n");
return 0;
+ }
+ } else {
+ mode_odt_enable = 0x0; /* Default disabled */
+ if (odt_wr_cfg || odt_rd_cfg) {
+ /*
+ * Bits 6 and 2 in Extended MRS(1)
+ * Bit 2 == 0x04 == 75 Ohm, with 2 DIMM modules.
+ * Bit 6 == 0x40 == 150 Ohm, with 1 DIMM module.
+ */
+ mode_odt_enable = 0x40; /* 150 Ohm */
+ }
+
+ ddr->sdram_mode =
+ (0
+ | (1 << (16 + 10)) /* DQS Differential disable */
+ | (add_lat << (16 + 3)) /* Additive Latency in EMRS1 */
+ | (mode_odt_enable << 16) /* ODT Enable in EMRS1 */
+ | ((twr_clk >> 1) << 9) /* Write Recovery Autopre */
+ | (caslat << 4) /* caslat */
+ | (burstlen << 0) /* Burst length */
+ );
}
debug("DDR:sdram_mode=0x%08x\n", ddr->sdram_mode);
+ /*
+ * Clear EMRS2 and EMRS3.
+ */
+ ddr->sdram_mode2 = 0;
+ debug("DDR: sdram_mode2 = 0x%08x\n", ddr->sdram_mode2);
+
switch (spd.refresh) {
case 0x00:
case 0x80:
@@ -440,6 +674,23 @@ long int spd_sdram()
ddr->sdram_interval = ((refresh_clk & 0x3fff) << 16) | 0x100;
debug("DDR:sdram_interval=0x%08x\n", ddr->sdram_interval);
+ /*
+ * SDRAM Cfg 2
+ */
+ odt_cfg = 0;
+ if (odt_rd_cfg | odt_wr_cfg) {
+ odt_cfg = 0x2; /* ODT to IOs during reads */
+ }
+ if (spd.mem_type == SPD_MEMTYPE_DDR2) {
+ ddr->sdram_cfg2 = (0
+ | (0 << 26) /* True DQS */
+ | (odt_cfg << 21) /* ODT only read */
+ | (1 << 12) /* 1 refresh at a time */
+ );
+
+ debug("DDR: sdram_cfg2 = 0x%08x\n", ddr->sdram_cfg2);
+ }
+
#ifdef CFG_DDR_SDRAM_CLK_CNTL /* Optional platform specific value */
ddr->sdram_clk_cntl = CFG_DDR_SDRAM_CLK_CNTL;
#else
@@ -462,11 +713,22 @@ long int spd_sdram()
*
* sdram_cfg[0] = 1 (ddr sdram logic enable)
* sdram_cfg[1] = 1 (self-refresh-enable)
- * sdram_cfg[6:7] = 2 (SDRAM type = DDR SDRAM)
+ * sdram_cfg[5:7] = (SDRAM type = DDR SDRAM)
+ * 010 DDR 1 SDRAM
+ * 011 DDR 2 SDRAM
* sdram_cfg[12] = 0 (32_BE =0 , 64 bit bus mode)
* sdram_cfg[13] = 0 (8_BE =0, 4-beat bursts)
*/
- sdram_cfg = 0xC2000000;
+ if (spd.mem_type == SPD_MEMTYPE_DDR)
+ sdram_type = 2;
+ else
+ sdram_type = 3;
+
+ sdram_cfg = (0
+ | (1 << 31) /* DDR enable */
+ | (1 << 30) /* Self refresh */
+ | (sdram_type << 24) /* SDRAM type */
+ );
/* sdram_cfg[3] = RD_EN - registered DIMM enable */
if (spd.mod_attr & 0x02)