I am recently working on Nexus 9, which is based on 64-bit Tegra K1 chipset. I want to know more information about this specified chipset, such as the information of the mode registers, the EMC_MRW/EMC_MRR command configuration, etc.
I used to download the file “TegraK1_TRM_DP06905001_public_v03p.pdf” from the Nvidia website, but the information provided in this manual is basically about 32-bit. For example, the EMC_MRW/EMC_MRR command is configured with 32-bit.
I wonder where can I get the detailed information about 64-bit Tegra K1. If anyone know there are some manual or white paper, could you please send me a version, or leave a link?
If so, I see conflicting specifications which confuse things. For chipset it says Tegra K1, but for GPU it says Kepler DX1. The Tegra K1 SoC uses 32-bit ARM Cortex A15 CPU cores, it isn’t until you get to the Tegra X1 that 64-bit cores are used…which would match the Kepler DX1 listed (Denver/X1).
Tegra K1 have two versions, One is 32-bit with Quad A15 CPUs, Another is 64-bit with Dual Denver CPUs
Refer to the below link: http://blogs.nvidia.com/blog/2014/08/11/tegra-k1-denver-64-bit-for-android/
Google Nexus9 has a 64bit version TK1. there is no public released TRM for 64bit TK1
About the EMC memory controller, both chip have same design.
The TRM have same description about EMC_MRW and EMC_MRR for these two chips, they are all 32bit
However, when I tried to use EMC_MRW cammand to write a mode register (MR16), in the exact format as described with 32-bit, nothing happens. MR16 is in charge of turning some individual memory banks into no_refresh state. In the no_refresh state, the data might get loss, but power can be saved. When I tried to use EMC_MRW to write MR16, I found that the value in MR16 does not change.
Do you have any idea what the problem might be? Thanks a lot in advance.