On Tue, 19 May 2015 08:20:24 -0700 (PDT) sufi al hussaini hassani kamili raheemi <sufialhussa...@gmail.com> wrote:
> Has anyone tried this specific DRAM (Samsung's SDRAM 'K4B1G1646G BCK0')? Regarding the "has anyone tried" part of the question, this particular DDR3 chip does not seem to be very popular, according to the information from http://linux-sunxi.org/DDR3 However this should not be a problem and DRAM should work just fine. Assuming that the board itself is not defective. > I was wondering if someone could provide me with '[dram_para]' for the FEX > file for this specific RAM. The FEX file is not used by U-Boot at all. All the DRAM parameters are configured in the U-Boot defconfig files. And this is explained at: http://linux-sunxi.org/Mainline_U-boot#DRAM_Settings The http://linux-sunxi.org/Fex_Guide#SDRAM section probably needs to be adjusted and explicitly say that you don't want to touch this stuff unless using the Allwinner's boot0 bootloader and/or livesuit. If there is some other part of the wiki with misleading information, please let us know. -- Best regards, Siarhei Siamashka > > Thanks. > > On Tuesday, May 19, 2015 at 2:56:30 PM UTC+4, sufi al hussaini hassani > kamili raheemi wrote: > > > > I have a board that's got A20 with Samsung's SDRAM 'K4B1G1646G BCK0'. > > > > The problem I'm facing now is that I'm not able to get it to boot. I keep > > getting the following on debug UART: > > > > U-Boot SPL 2014.04-10706-g36080eb (Aug 19 2014 - 16:42:16) > > DRAM:Timeout initialising DRAM > > > > resetting ... > > > > .... (Repeats infinitely) > > > > > > I suspected that the (old) '[dram_para]' in my FEX file was causing this, > > as it was configured for 'K4B4G1646D' (which is widely used). > > So, I edited the FEX file based on the info I could gather from the > > SDRAM's datasheet. It now looks like this: > > > > > > [dram_para] > > dram_baseaddr = 0x40000000 > > dram_clk = 384 > > dram_type = 3 > > dram_rank_num = 1 > > dram_chip_density = 1024 > > dram_io_width = 16 > > dram_bus_width = 32 > > dram_cas = 9 > > dram_zq = 0x7f > > dram_odt_en = 0 > > dram_size = 256 > > dram_tpr0 = 0x42d899b7 > > dram_tpr1 = 0xa090 > > dram_tpr2 = 0x22a00 > > dram_tpr3 = 0x0 > > dram_tpr4 = 0x0 > > dram_tpr5 = 0x0 > > dram_emr1 = 0x4 > > dram_emr2 = 0x10 > > dram_emr3 = 0x0 > > > > I tried booting with this but to no avail. The problem persists (same > > error). > > > > I looked for ways to get the DRAM info directly from the hardware and > > found meminfo in sunxi tools. > > I was able to compile (and run) it (on a A20 based commercial board), but > > I just can't figure out how to get it running on my board. > > > > Now, I'm confused- whether just setting the correct values in my FEX would > > suffice or would I have to rebuild U-Boot. > > I would appreciate if someone could point me in the right direction to > > solve this problem. > > > > Thanks. > > -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
