Tool/software: Linux
Hi,
I was attempting to work out the LISA Map values for the 4GB space that we have on our custom board. Please could you let me know if I am on the right track?
Firstly, I understand that only 2GB of the total 4GB space can be used or shared by all cores of the AM5728 and the upper 2GB can only be accessed by the MPU. I came up with the following values for the LISA Map
dmm_lisa_map_0 = 0x0
dmm_lisa_map_1 = 0x0
dmm_lisa_map_2 = 0x8074_0300 (SYS_ADDR = 0x8000_0000, SYS_SIZE = 2GB, SDRC_INTL = 128-byte interleaving, SDRC_ADDRSPC = 0x00 (SDRAMs), SDRC_MAP = EMIF1 and EMIF2 interleaved, SDRC_ADDR = 0x0000_0000)
For the MPU this corresponds to an address range of 0x00 8000_0000 to 0x00 FFFF_FFFF and a physical external address range of 0x0000_0000 to 0x7FFF_FFFF
dmm_lisa_map_3 = 0x0074_0380 (SYS_ADDR = 0x0000_0000, SYS_SIZE = 2GB, SDRC_INTL = 128-byte interleaving, SDRC_ADDRSPC = 0x00 (SDRAMs), SDRC_MAP = EMIF1 and EMIF2 interleaved, SDRC_ADDR = 0x8000_0000)
From what I understood this will correspond to an MPU address range of 0x01_0000_0000 to 0x01_8000_0000 and a physical external address range of 0x8000_0000 to 0xFFFF_FFFF.
1. Firstly, is this configuration and my understanding correct?
2. I noticed that the SDRAM init (in u-boot) routine writes lisa_map values to both the DMM_LISA_MAP_i and MA_LISA_MAP_i. Will writing dmm_lisa_map_3 to the DMM_LISA_MAP_i register cause problems because this is intended for the extended space? Should this value be written to the MA_LISA_MAP_i register only?
Thanks very much.
Regards,
Shaunak
