[U-Boot] [PATCH 2/8] powerpc/mpc8xxx: Add fine timing support for DDR3
York Sun
yorksun at freescale.com
Fri Aug 17 20:22:37 CEST 2012
When the DDR3 speed goes higher, we need to utilize fine offset
from SPD.
Signed-off-by: York Sun <yorksun at freescale.com>
---
arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c | 25 +++++++++++++++++-----
arch/powerpc/cpu/mpc8xxx/ddr/interactive.c | 22 ++++++++++++++-----
arch/powerpc/include/asm/fsl_ddr_dimm_params.h | 1 +
include/ddr_spd.h | 7 +++++-
4 files changed, 42 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c b/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c
index d0a5466..3e7c269 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c
@@ -1,5 +1,5 @@
/*
- * Copyright 2008-2009 Freescale Semiconductor, Inc.
+ * Copyright 2008-2012 Freescale Semiconductor, Inc.
* Dave Liu <daveliu at freescale.com>
*
* calculate the organization and timing parameter
@@ -90,6 +90,7 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
{
unsigned int retval;
unsigned int mtb_ps;
+ int ftb_10th_ps;
int i;
if (spd->mem_type) {
@@ -197,6 +198,14 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
pdimm->mtb_ps = mtb_ps;
/*
+ * FTB - fine timebase
+ * use 1/10th of ps as our unit to avoid floating point
+ * eg, 10 for 1ps, 25 for 2.5ps, 50 for 5ps
+ */
+ ftb_10th_ps =
+ ((spd->ftb_div & 0xf0) >> 4) * 10 / (spd->ftb_div & 0x0f);
+ pdimm->ftb_10th_ps = ftb_10th_ps;
+ /*
* sdram minimum cycle time
* we assume the MTB is 0.125ns
* eg:
@@ -204,7 +213,8 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
* =12 MTB (1.5ns) ->DDR3-1333
* =10 MTB (1.25ns) ->DDR3-1600
*/
- pdimm->tCKmin_X_ps = spd->tCK_min * mtb_ps;
+ pdimm->tCKmin_X_ps = spd->tCK_min * mtb_ps +
+ (spd->fine_tCK_min * ftb_10th_ps) / 10;
/*
* CAS latency supported
@@ -222,7 +232,8 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
* DDR3-1333H 108 MTB (13.5ns)
* DDR3-1600H 90 MTB (11.25ns)
*/
- pdimm->tAA_ps = spd->tAA_min * mtb_ps;
+ pdimm->tAA_ps = spd->tAA_min * mtb_ps +
+ (spd->fine_tAA_min * ftb_10th_ps) / 10;
/*
* min write recovery time
@@ -239,7 +250,8 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
* DDR3-1333H 108 MTB (13.5ns)
* DDR3-1600H 90 MTB (11.25)
*/
- pdimm->tRCD_ps = spd->tRCD_min * mtb_ps;
+ pdimm->tRCD_ps = spd->tRCD_min * mtb_ps +
+ (spd->fine_tRCD_min * ftb_10th_ps) / 10;
/*
* min row active to row active delay time
@@ -257,7 +269,8 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
* DDR3-1333H 108 MTB (13.5ns)
* DDR3-1600H 90 MTB (11.25ns)
*/
- pdimm->tRP_ps = spd->tRP_min * mtb_ps;
+ pdimm->tRP_ps = spd->tRP_min * mtb_ps +
+ (spd->fine_tRP_min * ftb_10th_ps) / 10;
/* min active to precharge delay time
* eg: tRAS_min =
@@ -277,7 +290,7 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
* DDR3-1600H 370 MTB (46.25ns)
*/
pdimm->tRC_ps = (((spd->tRAS_tRC_ext & 0xf0) << 4) | spd->tRC_min_lsb)
- * mtb_ps;
+ * mtb_ps + (spd->fine_tRC_min * ftb_10th_ps) / 10;
/*
* min refresh recovery delay time
* eg: tRFC_min =
diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/interactive.c b/arch/powerpc/cpu/mpc8xxx/ddr/interactive.c
index 5b72437..738c808 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/interactive.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/interactive.c
@@ -1,5 +1,5 @@
/*
- * Copyright 2010-2011 Freescale Semiconductor, Inc.
+ * Copyright 2010-2012 Freescale Semiconductor, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -1121,11 +1121,21 @@ void ddr3_spd_dump(const ddr3_spd_eeprom_t *spd)
"therm_sensor SDRAM Thermal Sensor");
PRINT_NXS(33, spd->device_type,
"device_type SDRAM Device Type");
-
- printf("%-3d-%3d: ", 34, 59); /* Reserved, General Section */
-
- for (i = 34; i <= 59; i++)
- printf("%02x ", spd->res_34_59[i - 34]);
+ PRINT_NXS(34, spd->fine_tCK_min,
+ "fine_tCK_min Fine offset for tCKmin");
+ PRINT_NXS(35, spd->fine_tAA_min,
+ "fine_tAA_min Fine offset for tAAmin");
+ PRINT_NXS(36, spd->fine_tRCD_min,
+ "fine_tRCD_min Fine offset for tRCDmin");
+ PRINT_NXS(37, spd->fine_tRP_min,
+ "fine_tRP_min Fine offset for tRPmin");
+ PRINT_NXS(38, spd->fine_tRC_min,
+ "fine_tRC_min Fine offset for tRCmin");
+
+ printf("%-3d-%3d: ", 39, 59); /* Reserved, General Section */
+
+ for (i = 39; i <= 59; i++)
+ printf("%02x ", spd->res_39_59[i - 39]);
puts("\n");
diff --git a/arch/powerpc/include/asm/fsl_ddr_dimm_params.h b/arch/powerpc/include/asm/fsl_ddr_dimm_params.h
index 982b809..ffe4db8 100644
--- a/arch/powerpc/include/asm/fsl_ddr_dimm_params.h
+++ b/arch/powerpc/include/asm/fsl_ddr_dimm_params.h
@@ -43,6 +43,7 @@ typedef struct dimm_params_s {
/* DIMM timing parameters */
unsigned int mtb_ps; /* medium timebase ps, only for ddr3 */
+ unsigned int ftb_10th_ps; /* fine timebase, in 1/10 ps, only for ddr3 */
unsigned int tAA_ps; /* minimum CAS latency time, only for ddr3 */
unsigned int tFAW_ps; /* four active window delay, only for ddr3 */
diff --git a/include/ddr_spd.h b/include/ddr_spd.h
index a9230b9..9e74d87 100644
--- a/include/ddr_spd.h
+++ b/include/ddr_spd.h
@@ -221,7 +221,12 @@ typedef struct ddr3_spd_eeprom_s {
unsigned char therm_ref_opt; /* 31 SDRAM Thermal and Refresh Opts */
unsigned char therm_sensor; /* 32 Module Thermal Sensor */
unsigned char device_type; /* 33 SDRAM device type */
- unsigned char res_34_59[26]; /* 34-59 Reserved, General Section */
+ int8_t fine_tCK_min; /* 34 Fine offset for tCKmin */
+ int8_t fine_tAA_min; /* 35 Fine offset for tAAmin */
+ int8_t fine_tRCD_min; /* 36 Fine offset for tRCDmin */
+ int8_t fine_tRP_min; /* 37 Fine offset for tRPmin */
+ int8_t fine_tRC_min; /* 38 Fine offset for tRCmin */
+ unsigned char res_39_59[21]; /* 39-59 Reserved, General Section */
/* Module-Specific Section: Bytes 60-116 */
union {
--
1.7.0.4
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