tree cb5ba8da06d816f245d2ff0dc9b10e46d2b26cfc
parent 3f86ca372070ced7cdf6a7f4f9e4faf4738b727b
author Zev Weiss <zev@bewilderbeest.net> 1645834993 +0000
committer Zev Weiss <zev@bewilderbeest.net> 1665791939 -0700

fru-device: use FRUReader API to simplify FRU parsing I/O

FRUReader::read() abstracts away SMBus block-size limits, which allows
us to replace the loop at the end of readFRUContents() with a single
reader.read() call.

FRUReader also (due its caching) eliminates the need to share I/O
buffers between the IPMI and Tyan parsers.  We can thus restructure the
parsing code to try each of them separately in turn, reusing the same
FRUReader to avoid duplicating I/O.  This eliminates the findFRUHeader()
function (each parser just looks for a header where it expects it);
tests are updated accordingly to exercise readFRUContents() instead.

testFRUData was generated via https://github.com/ipmitool/frugen using
the '--ascii' flag and the following JSON:

    {
        "chassis": {
            "type": 17,
            "pn": "OBMC_TEST_CHASSIS",
            "serial": "XYZ123"
        },
        "board": {
            "mfg": "OpenBMC Project",
            "pname": "OBMC_TEST_BOARD",
            "serial": "ABC012",
            "pn": "BOARD_PARTNUM"
        },
        "product": {
            "lang": 1,
            "mfg": "OpenBMC Project",
            "pname": "OBMC_TEST_PRODUCT",
            "serial": "9999",
        }
    }

Tested: on an ASRock Rack romed8hm3, fru-device successfully recognizes
and parses the baseboard FRU EEPROM as it did prior to this patch.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Change-Id: I215bb2f6da0e1b23e5f52727c749993452c031e9