ichspi: add ICH/PCH flash descriptor decoding via FDOC/FDOD

Based on the work of Matthias 'mazzoo' Wenzel this patch adds pretty
printing of those ICH/PCH flash descriptor sections that are
cached/mapped by the chipset (and which are therefore reachable via
FDOC/FDOD registers).

this includes the following:
- content section:
    describes the image and some generic properties (number of
    sections, offset of sections, PCH/ICH and MCH/PROC strap
    offsets and lengths)
- component section:
    identify the different SPI flash chips and their capabilities.
- region section
    similarly to a partition table this describes the different regions.
    the content of FLREG* is derived from this section.
- master section
    defines SPI master (host, ME, GbE) access rights of the
    individual regions. the content of PR* is derived from this section.

this is only a part of the data included in the descriptor. other
information can be retrieved from a complete binary dump of the
descriptor region only.

this patch also adds macros and pretty printing for "Vendor Specific
Component Capabilities" registers: there are two of them: lower and
upper. they describe the properties of the address space divided by
FPBA (which allows to use multiple flash chips or partitions with
different properties). the properties of all supported flash chips
(together with their RDIDs) are stored in the same format in table
in a descriptor section (which is used by the ME apparently). a
later patch will use the macros outside of ichspi.c which is the
reason why the prettyprinting function and the register bit macros
are not defined in ichspi.c but ich_descriptors.h (else they would
be moved in the follow-up patch).

because this patch relies on (compiler) implementation-specific
layouting of bit-fields, it checks for correct layout before taking
any action on runtime.

Corresponding to flashrom svn r1443.

Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
4 files changed