Hi Harsha, On Sun, 5 Jan 2025 at 23:36, Harsha Vardhan V M <[email protected]> wrote: > > I would like to propose a new command for U-Boot's fuse programming > functionality to address the challenges posed by the current > implementation. While the existing fuse prog command works well for > programming individual fuse values, it becomes cumbersome especially > when dealing with large-scale programming requirements. > > Current Command: fuse prog [-y] <bank> <word> <hexval> [<hexval>...] > > This command programs one or more fuse words starting from a specific > <bank> and <word> with the hex values given as input. > > While functional, it lacks the efficiency and robustness needed for > programming a significant number of fuses or handling structured fuse > configuration data. Repeatedly specifying values for each fuse bank and > word is not only time-consuming but also prone to errors during manual > input or scripting. This approach does not leverage the ability to > process pre-structured data in memory. For users with complex > programming needs, the current method becomes an obstacle rather than a > tool. > > Proposed Command: fuse writebuff > > NAME > fuse writebuff - Program fuse data using a memory-based structured buffer. > > SYNOPSIS > fuse writebuff <command_id> <addr> > > DESCRIPTION > The fuse writebuff command provides a new method for programming fuses > by leveraging a structured buffer in memory. Instead of requiring > explicit <bank> and <word> parameters for each fuse word, this command > operates on a structured buffer in memory at <addr>, that contains all > the necessary data and programming details, allowing bulk or structured > programming in a single operation. This approach simplifies workflows, > reduces manual input, and improves flexibility for complex programming > scenarios. > > PARAMETERS > • <command_id> > Specifies the programming mode or indicates how the buffer data should > be interpreted. This parameter is a u32 value that identifies the > operational context or configuration for the programming process. > Examples of command_id usage might include: > • A programming mode > • A specific interpretation of the buffer layout. > • A mode for validating the buffer before programming. > > • <addr> > The starting memory address of the buffer containing the structured fuse > programming data. This parameter is of type ulong and points to a block > of memory where the programming data and any associated metadata reside. > > USAGE > The fuse writebuff command reads the buffer at <addr> and interprets it > according to the specified <command_id>. The structure of the buffer > should contain all necessary details for programming fuses, such as the > values to be written to the fuse, optional metadata for validation or > programming constraints and any configuration data required for the > operation. > > EXAMPLES > 1. fuse writebuff 1 0x80000000 > In this example: > • command_id is 1, specifying a particular programming mode or a > buffer format. > • addr is 0x80000000, pointing to the starting memory address where > the structured buffer resides. > > RETURN VALUES > • 0: The operation was successful. > • Non-zero: An error occurred during the operation. Errors may include > invalid command_id, inaccessible memory at <addr>, or issues with the > buffer contents. > > The corresponding function, fuse_writebuff(u32 command_id, ulong addr), > would process this data in a single invocation. This approach > significantly streamlines and simplifies workflows where fuse > programming involves predefined rules or structured data, enabling users > to prepare a struct buffer in memory that encapsulates the entire fuse > programming configuration. I believe fuse writebuff simplifies > workflows, reduces error risks, and provides the extensibility needed > for advanced usage scenarios like programming large or complex fuse > configurations. > > Request for Feedback > > Does this proposal look good? If so, I will start to work on an RFC > patch to implement the proposed changes.
What format is the buffer in? Is it a text file? Regards, Simon
