Fork of alistair23 Linux kernel for reMarkable from https://github.com/alistair23/linux
ebceaf435c
This feature is telling how to configure cache type on 4 different transfer types: Data Read, Desc Read, Data Write and Desc write. For each transfer type, controller has a 4-bit register field to enable different cache type. Quoted from DWC3 data book Table 6-5 Cache Type Bit Assignments: ---------------------------------------------------------------- MBUS_TYPE| bit[3] |bit[2] |bit[1] |bit[0] ---------------------------------------------------------------- AHB |Cacheable |Bufferable |Privilegge |Data AXI3 |Write Allocate|Read Allocate|Cacheable |Bufferable AXI4 |Allocate Other|Allocate |Modifiable |Bufferable AXI4 |Other Allocate|Allocate |Modifiable |Bufferable Native |Same as AXI |Same as AXI |Same as AXI|Same as AXI ---------------------------------------------------------------- Note: The AHB, AXI3, AXI4, and PCIe busses use different names for certain signals, which have the same meaning: Bufferable = Posted Cacheable = Modifiable = Snoop (negation of No Snoop) In most cases, driver support is not required unless the default values of registers are not correct *and* DWC3 node has enabled dma-coherent. So far we have observed USB device detect failure on some Layerscape platforms if this programming was not applied. Related struct: struct dwc3_cache_type { u8 transfer_type_datard; u8 transfer_type_descrd; u8 transfer_type_datawr; u8 transfer_type_descwr; }; Signed-off-by: Ran Wang <ran.wang_1@nxp.com> Reviewed-by: Jun Li <jun.li@nxp.com> |
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arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
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 |
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.