mainlining shenanigans
Under certain circumstances, the timing settings calculated by
the FSMC NAND controller driver were inaccurate.
These settings led to incorrect data reads or fallback to
timing mode 0 depending on the NAND chip used.
The timing computation did not take into account the following
constraint given in SPEAr3xx reference manual:
twait >= tCEA - (tset * TCLK) + TOUTDEL + TINDEL
Enhance the timings calculation by taking into account this
additional constraint.
This change has no impact on slow timing modes such as mode 0.
Indeed, on mode 0, computed values are the same with and
without the patch.
NANDs which previously stayed in mode 0 because of fallback to
mode 0 can now work at higher speeds and NANDs which were not
working at all because of the corrupted data work at high
speeds without troubles.
Overall improvement on a Micron/MT29F1G08 (flash_speed tool):
mode0 mode3
eraseblock write speed 3220 KiB/s 4511 KiB/s
eraseblock read speed 4491 KiB/s 7529 KiB/s
Fixes:
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||
---|---|---|
arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.