[M] Change in coreboot[main]: drivers/intel/fsp2_0: Add option to control debug log level using CBFS

[Subrata Banik (Code Review)]

Attention is currently required from: Andrey Petrov, Intel coreboot Reviewers, Julius Werner, Ronak Kanabar.

Hello Andrey Petrov, Intel coreboot Reviewers, Julius Werner, Ronak Kanabar,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/86001?usp=email

to look at the new patch set (#2).

Change subject: drivers/intel/fsp2_0: Add option to control debug log level using CBFS
......................................................................

drivers/intel/fsp2_0: Add option to control debug log level using CBFS

This commit introduces a new Kconfig option,
FSP_DEBUG_LOG_LEVEL_USING_CBFS, which allows controlling the FSP debug
log level using CBFS RAW binary files.

If this option is enabled, the following files will be used to determine
the log levels:

- fsp_pcd_debug_level: For the overall FSP debug log level.

- fsp_mrc_debug_level: For the MRC (Memory Reference Code) debug log
  level.

The values in these files should correspond to the FSP_LOG_LEVEL_* enum
values.

See the Kconfig help text for more details.

If this option is disabled, the log levels will be determined by calling
into fsp_map_console_log_level API.

This change allows for more flexibility in controlling the FSP debug log
level, especially in cases of debugging silicon firmware issues with a
debug AP FW binary.

This capability is particularly useful when debugging issues that
require examining both silicon and MRC logs simultaneously.

BUG=b:227151510
TEST=Able to control the FSP debug log based on CBFS options

To inject the fsp_pcd_debug_level and fsp_mrc_debug_level CBFS files
with the desired log level, run:

```
cbfstool image-fatcat.serial.bin add-int -i 5 -n option/fsp_pcd_debug_level

cbfstool image-fatcat.serial.bin add-int -i 5 -n option/fsp_mrc_debug_level
```

With both fsp_pcd_debug_level and fsp_mrc_debug_level present in the RO
CBFS, both the silicon firmware and MRC behave as debug binaries.

To verify the presence of both log-level RAW CBFS binaries in the CBFS RO
slot, run:

```
sudo cbfstool fatcat/image-rex0.serial.bin print | grep fsp_
```

This should output:

```
option/fsp_mrc_debug_level            0x88e40    raw                 8 none
option/fsp_pcd_debug_level            0x2a7400   raw                 8 none
```

Change-Id: I2c14d26021dd0048fa24024119df857e216f18bd
Signed-off-by: Subrata Banik 
---
M src/drivers/intel/fsp2_0/Kconfig
M src/drivers/intel/fsp2_0/debug.c
M src/drivers/intel/fsp2_0/include/fsp/debug.h
3 files changed, 74 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/01/86001/2