On 17/04/2024 05:15, Florian Fainelli wrote: > > > On 4/15/2024 2:10 AM, Arınç ÜNAL wrote: >> On 15.04.2024 10:57, Krzysztof Kozlowski wrote: >>> On 14/04/2024 22:21, Arınç ÜNAL wrote: >>>> NVRAM is described as both flash device partition and memory mapped >>>> NVMEM. >>>> This platform stores NVRAM on flash but makes it also memory accessible. >>>> >>>> As device partitions are described in board DTS, the nvram node must >>>> also >>> >>> Sorry, but we do not talk about partitions. Partitions are indeed board >>> property. But the piece of hardware, so NVMEM, is provided by SoC. >>> >>>> be defined there as its address and size will be different by board. >>>> It has >>>> been widely described on at least bcm4709 and bcm47094 SoC board DTS >>>> files >>>> here. >>> >>> These not proper arguments. What you are saying here is that SoC does no >>> have nvram at address 0x1c08000. Instead you are saying there some sort >>> of bus going out of SoC to the board and on the board physically there >>> is some NVRAM sort of memory attached to this bus. >> >> Yes that is the case. NVRAM is stored on a partition on the flash. On the >> Broadcom NorthStar platform, the NAND flash base is 0x1c000000, the NOR >> flash base is 0x1e000000. >> >> For the board in this patch, the flash is a NAND flash. The NVRAM partition >> starts at address 0x00080000. Therefore, the NVRAM component's address is >> 0x1c080000. > > Because the flash is memory mapped into the CPU's address space, a > separate node was defined since it is not part of the "soc" node which > describes the bridge that connects all of the peripherals. > > Whether we should create an additional bus node which describes the > bridge being used to access the flash devices using the MMIO windows is > debatable. Rafal, what do you think? Sorry guys, I don't get. I don't know the addresses neither the names like Broadcom Northstar, so this does not clarify me at all. Please answer the simple questions: 1. Is NAND flash part of SoC? 2. If not, is NAND flash provided by Broadcom or anyone else? Best regards, Krzysztof
