Change in coreboot[master]: security/intel/txt: Split of microcode error type printing

[Angel Pons (Code Review)]

Attention is currently required from: Arthur Heymans.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54092 )

Change subject: security/intel/txt: Split of microcode error type printing
......................................................................

Patch Set 3:

(6 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/54092/comment/240be392_eab01beb 
PS3, Line 7: of
nit: `off` or `out`

File src/security/intel/txt/Makefile.inc:

https://review.coreboot.org/c/coreboot/+/54092/comment/b03e454f_3fa4db16 
PS3, Line 3: bootblock-y += logging.c
This hunk shouldn't be part of this commit.

File src/security/intel/txt/logging.c:

https://review.coreboot.org/c/coreboot/+/54092/comment/2acb6810_f828366a 
PS3, Line 12: microcode
Document 315168-017 calls these "processor-initiated Intel TXT shutdowns". I'd replace `microcode` with `processor`.

https://review.coreboot.org/c/coreboot/+/54092/comment/ad0d67cb_ad44fe9d 
PS3, Line 14: types
Maybe call this `names` to avoid confusion with the `type` parameter?

https://review.coreboot.org/c/coreboot/+/54092/comment/d73e2c28_d92a11ac 
PS3, Line 31: 	};
There's a much better way to do this:

const char *intel_txt_processor_error_type(uint8_t type)
 {
    static const char *const names[] = {
    	[0]  = "Legacy Shutdown",
    	[5]  = "Load memory type error in ACM area",
    	[6]  = "Unrecognized ACM format",
    	[7]  = "Failure to authenticate",
    	[8]  = "Invalid ACM format",
    	[9]  = "Unexpected Snoop hit",
    	[10] = "Invalid event",
    	[11] = "Invalid MLE",
    	[12] = "Machine check event",
    	[13] = "VMXAbort",
    	[14] = "AC memory corruption",
    	[15] = "Illegal voltage/bus ratio",
    };
    return type < ARRAY_SIZE(names) && names[type] ? names[type] : "Unknown";
 }

This can be improved even further if one makes the function print the strings directly, and return nothing:

void intel_txt_log_processor_error(int loglevel, uint8_t type)
 {
    static const char *const names[] = {
    	[0]  = "Legacy Shutdown",
    	[5]  = "Load memory type error in ACM area",
    	[6]  = "Unrecognized ACM format",
    	[7]  = "Failure to authenticate",
    	[8]  = "Invalid ACM format",
    	[9]  = "Unexpected Snoop hit",
    	[10] = "Invalid event",
    	[11] = "Invalid MLE",
    	[12] = "Machine check event",
    	[13] = "VMXAbort",
    	[14] = "AC memory corruption",
    	[15] = "Illegal voltage/bus ratio",
    };
    if (type < ARRAY_SIZE(names) && names[type])
    	printk(loglevel, "Error condition: %s\n", names[type]);
    else
    	printk(loglevel, "Error condition: Unknown %u\n", type);
 }

https://review.coreboot.org/c/coreboot/+/54092/comment/5299c379_5898af47 
PS3, Line 58: intel_txt_microcode_error_type
For another patch: This shouldn't be called when the error cause is external.