[U-Boot] [PATCH V3 19/32] mx6q_4x_mt41j128.cfg: add comments

Thu Oct 4 03:47:21 CEST 2012

Signed-off-by: Troy Kisky <troy.kisky at boundarydevices.com>
---
 board/freescale/imx/ddr/mx6q_4x_mt41j128.cfg |   55 ++++++++++++++++++++++----
 1 file changed, 47 insertions(+), 8 deletions(-)

diff --git a/board/freescale/imx/ddr/mx6q_4x_mt41j128.cfg b/board/freescale/imx/ddr/mx6q_4x_mt41j128.cfg
index 84823f8..b859e2f 100644
--- a/board/freescale/imx/ddr/mx6q_4x_mt41j128.cfg
+++ b/board/freescale/imx/ddr/mx6q_4x_mt41j128.cfg
@@ -53,7 +53,6 @@ WRITE_ENTRY1(IOM_DRAM_SDQS0, 0x00000030)
 WRITE_ENTRY1(IOM_DRAM_SDQS1, 0x00000030)
 WRITE_ENTRY1(IOM_DRAM_SDQS2, 0x00000030)
 WRITE_ENTRY1(IOM_DRAM_SDQS3, 0x00000030)
-
 WRITE_ENTRY1(IOM_DRAM_SDQS4, 0x00000030)
 WRITE_ENTRY1(IOM_DRAM_SDQS5, 0x00000030)
 WRITE_ENTRY1(IOM_DRAM_SDQS6, 0x00000030)
@@ -63,7 +62,6 @@ WRITE_ENTRY1(IOM_DRAM_DQM0, 0x00020030)
 WRITE_ENTRY1(IOM_DRAM_DQM1, 0x00020030)
 WRITE_ENTRY1(IOM_DRAM_DQM2, 0x00020030)
 WRITE_ENTRY1(IOM_DRAM_DQM3, 0x00020030)
-
 WRITE_ENTRY1(IOM_DRAM_DQM4, 0x00020030)
 WRITE_ENTRY1(IOM_DRAM_DQM5, 0x00020030)
 WRITE_ENTRY1(IOM_DRAM_DQM6, 0x00020030)
@@ -81,65 +79,105 @@ WRITE_ENTRY1(IOM_DRAM_SDBA2, 0x00000000)
 
 WRITE_ENTRY1(IOM_DRAM_SDODT0, 0x00003030)
 WRITE_ENTRY1(IOM_DRAM_SDODT1, 0x00003030)
+
 WRITE_ENTRY1(IOM_GRP_B0DS, 0x00000030)
 WRITE_ENTRY1(IOM_GRP_B1DS, 0x00000030)
-
 WRITE_ENTRY1(IOM_GRP_B2DS, 0x00000030)
 WRITE_ENTRY1(IOM_GRP_B3DS, 0x00000030)
 WRITE_ENTRY1(IOM_GRP_B4DS, 0x00000030)
 WRITE_ENTRY1(IOM_GRP_B5DS, 0x00000030)
-
 WRITE_ENTRY1(IOM_GRP_B6DS, 0x00000030)
 WRITE_ENTRY1(IOM_GRP_B7DS, 0x00000030)
+
 WRITE_ENTRY1(IOM_GRP_ADDDS, 0x00000030)
+/* (differential input) */
 WRITE_ENTRY1(IOM_DDRMODE_CTL, 0x00020000)
-
+/* disable ddr pullups */
 WRITE_ENTRY1(IOM_GRP_DDRPKE, 0x00000000)
+/* (differential input) */
 WRITE_ENTRY1(IOM_GRP_DDRMODE, 0x00020000)
+/* 40 Ohm drive strength for cs0/1,sdba2,cke0/1,sdwe */
 WRITE_ENTRY1(IOM_GRP_CTLDS, 0x00000030)
 WRITE_ENTRY1(IOM_GRP_DDR_TYPE, 0x000C0000)
 
+/* Read data DQ Byte0-3 delay */
 WRITE_ENTRY1(MMDC_P0_MPRDDQBY0DL, 0x33333333)
 WRITE_ENTRY1(MMDC_P0_MPRDDQBY1DL, 0x33333333)
 WRITE_ENTRY1(MMDC_P0_MPRDDQBY2DL, 0x33333333)
 WRITE_ENTRY1(MMDC_P0_MPRDDQBY3DL, 0x33333333)
-
 WRITE_ENTRY1(MMDC_P1_MPRDDQBY0DL, 0x33333333)
 WRITE_ENTRY1(MMDC_P1_MPRDDQBY1DL, 0x33333333)
 WRITE_ENTRY1(MMDC_P1_MPRDDQBY2DL, 0x33333333)
 WRITE_ENTRY1(MMDC_P1_MPRDDQBY3DL, 0x33333333)
 
+/*
+ * MDMISC, mirroring, interleaved (row/bank/col)
+ */
 WRITE_ENTRY1(MMDC_P0_MDMISC, 0x00081740)
 
+/*
+ * MDSCR, con_req
+ */
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x00008000)
+/*
+ * MDCFG0, tRFC=0x56 clocks, tXS=0x5b clocks
+ * tXP=4 clocks, tXPDLL=13 clocks
+ * tFAW=24 clocks, cas=8 cycles
+ */
 WRITE_ENTRY1(MMDC_P0_MDCFG0, 0x555A7975)
+/*
+ * MDCFG1, tRDC=8, tRP=8, tRC=27,tRAS=20,tRPA=tRP+1,tWR=8
+ * tMRD=4, tCWL=6
+ */
 WRITE_ENTRY1(MMDC_P0_MDCFG1, 0xFF538E64)
+/*
+ * MDCFG2,tDLLK=512,tRTP=4,tWTR=4,tRRD=4
+ */
 WRITE_ENTRY1(MMDC_P0_MDCFG2, 0x01FF00DB)
 WRITE_ENTRY1(MMDC_P0_MDRWD, 0x000026D2)
 
 WRITE_ENTRY1(MMDC_P0_MDOR, 0x005B0E21)
 WRITE_ENTRY1(MMDC_P0_MDOTC, 0x09444040)
 WRITE_ENTRY1(MMDC_P0_MDPDC, 0x00025576)
+
+/*
+ * Mx6Q - 64 bit wide ddr
+ * last address is  (1<<28 (base) + 1<<30  - 1)  / (1<<25) =
+ * 	1<<3 + 1<<5 - 1 = 8 + 0x20 -1 = 0x27
+ */
+/* MDASP, CS0_END */
 WRITE_ENTRY1(MMDC_P0_MDASP, 0x00000027)
+/*
+ * MDCTL, CS0 enable, CS1 disabled, row=14, col=10, burst=8, width=64/32bit
+ * mx6q   : row+col+bank+width=14+10+3+3=30 = 1G
+ */
 WRITE_ENTRY1(MMDC_P0_MDCTL, 0x831A0000)
 
+/* MDSCR, con_req, LOAD MR2, CS0, A3,A10 set (CAS Write=6), RZQ/2 */
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x04088032)
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x0408803A)
+/* LOAD MR3, CS0 */
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x00008033)
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x0000803B)
+/* LOAD MR1, CS0, A1,A6 set Rtt=RZQ/2, ODI=RZQ/7 */
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x00428031)
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x00428039)
+/* LOAD MR0, CS0, A6,A8,A11 set CAS=8, WR=8, DLL reset */
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x09408030)
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x09408038)
 
+/* ZQ calibrate, CS0 */
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x04008040)
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x04008048)
 WRITE_ENTRY1(MMDC_P0_MPZQHWCTRL, 0xA1380003)
 WRITE_ENTRY1(MMDC_P1_MPZQHWCTRL, 0xA1380003)
+
+/* MDREF,  32KHz refresh, 4 refeshes each */
 WRITE_ENTRY1(MMDC_P0_MDREF, 0x00005800)
 WRITE_ENTRY1(MMDC_P0_MPODTCTRL, 0x00022227)
 WRITE_ENTRY1(MMDC_P1_MPODTCTRL, 0x00022227)
 
+/* MPDGCTRL0/1 DQS GATE*/
 WRITE_ENTRY1(MMDC_P0_MPDGCTRL0, 0x434B0350)
 WRITE_ENTRY1(MMDC_P0_MPDGCTRL1, 0x034C0359)
 WRITE_ENTRY1(MMDC_P1_MPDGCTRL0, 0x434B0350)
@@ -148,17 +186,18 @@ WRITE_ENTRY1(MMDC_P0_MPRDDLCTL, 0x4436383B)
 WRITE_ENTRY1(MMDC_P1_MPRDDLCTL, 0x39393341)
 WRITE_ENTRY1(MMDC_P0_MPWRDLCTL, 0x35373933)
 WRITE_ENTRY1(MMDC_P1_MPWRDLCTL, 0x48254A36)
-
 WRITE_ENTRY1(MMDC_P0_MPWLDECTRL0, 0x001F001F)
 WRITE_ENTRY1(MMDC_P0_MPWLDECTRL1, 0x001F001F)
-
 WRITE_ENTRY1(MMDC_P1_MPWLDECTRL0, 0x00440044)
 WRITE_ENTRY1(MMDC_P1_MPWLDECTRL1, 0x00440044)
 
+/* MPMUR0 - Complete calibration by forced measurement */
 WRITE_ENTRY1(MMDC_P0_MPMUR0, 0x00000800)
 WRITE_ENTRY1(MMDC_P1_MPMUR0, 0x00000800)
 
+/* MDSCR, enable ddr */
 WRITE_ENTRY1(MMDC_P0_MDSCR, 0x00000000)
+/* MAPSR, 1024 cycles idle before self-refresh */
 WRITE_ENTRY1(MMDC_P0_MAPSR, 0x00011006)
 
 /* set the default clock gate to save power */
-- 
1.7.9.5

