about i.mx6q boot question

[tom_y]

I want boot i.mx6q_arm2 from sd,I use 4GB DDR3,8 chips,BSP is L3.0.15_12.05.01.
question:
1:system no boot when Temperature less than 43 C.(CPU is PCIMX6Q6AVT10AB)
boot logs:
U-Boot 2009.08 ( 8鏈?10 2012 - 18:44:25)
U-Boot code: 27800720 -> 27831000 BSS: -> 278664B4
CPU: Freescale i.MX6 family TO0.0 at 792 MHz
Temperature: 60 C, calibration data 0x5874de7d
.......
2:4GB DDR3 only find 2GB(BANK 1,DDR3 type is EDJ4216BASE )
I modify mx6q_arm.h
#define CONFIG_NR_DRAM_BANKS 2
#define PHYS_SDRAM_1 CSD0_DDR_BASE_ADDR
#define PHYS_SDRAM_1_SIZE (2u*1024*1024*1024)
#define PHYS_SDRAM_2 CSD1_DDR_BASE_ADDR
#define PHYS_SDRAM_2_SIZE (2u*1024*1024*1024)
#define iomem_valid_addr(addr,size) \
((addr>=PHYS_SDRAM_1 && addr<=(PHYS_SDRAM_1+PHYS_SDRAM_1_SIZE)) \
|| (addr>=PHYS_SDRAM_2 && addr<=(PHYS_SDRAM_2+PHYS_SDRAM_2_SIZE)))
boot logs:
Board: MX6Q/SDL-ARM2:[ POR ]
Boot Device: SD
I2C: ready
RAM Configuration:
Bank #0: 00000000 0 kB
Bank #1: 00000000 0 kB
RAM Configuration:
Bank #0: 10000000 2 GB
Bank #1: 00000000 0 kB
What is cause? please help me, thanks!

[fei_liu]

Our internal LDO is a bit sensitive, output bulk capacitor must near the power pin very close, better within 100mil, refer oure SD Board design.

If you are debugging on our ARM2 CPU board, you may remove the 22uF capacitor on ARM_CAP to the back of CPU, weld it on the via.

Good Luck, waiting for your good news.

[tom_y]

second question is ok.