The next generation (revision 1) of the DFL EMIF feature device requires
support for more than 4 memory banks. It does not support the selective
clearing of memory banks. A capability register replaces the previous
control register, and contains a bitmask to indicate the presence of each
memory bank. This bitmask aligns with the previous control register
bitmask that served the same purpose. The control and capability
registers are treated like a C Union structure in order to support both
the new and old revisions of the EMIF device.
Signed-off-by: Debarati Biswas <debaratix.biswas@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Signed-off-by: Tianfei Zhang <tianfei.zhang@intel.com>
Reviewed-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220713130355.196115-1-tianfei.zhang@intel.com
This driver is for the EMIF private feature implemented under FPGA
Device Feature List (DFL) framework. It is used to expose memory
interface status information as well as memory clearing control.
The purpose of memory clearing block is to zero out all private memory
when FPGA is to be reprogrammed. This gives users a reliable method to
prevent potential data leakage.
[mdf@kernel.org: Fixed up ABI doc]
Reviewed-by: Tom Rix <trix@redhat.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Link: https://lore.kernel.org/r/20210107043714.991646-9-mdf@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>