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authorMiquel Raynal <miquel.raynal@bootlin.com>2019-11-17 18:34:01 +0100
committerMiquel Raynal <miquel.raynal@bootlin.com>2019-11-17 18:34:01 +0100
commit8389a7b909f252e74ea92b2794de8d660cfee96e (patch)
treea947f3080e953e4a44417389b3f2b69d4817be2e /Documentation/arm64/memory.rst
parentad39b5a1ed68032292794b41a5f9e41ea69f8052 (diff)
parent83cba933a6db1dd4d7ac85170f99461fbc339eff (diff)
downloadblackbird-op-linux-8389a7b909f252e74ea92b2794de8d660cfee96e.tar.gz
blackbird-op-linux-8389a7b909f252e74ea92b2794de8d660cfee96e.zip
Merge tag 'spi-nor/for-5.5' into mtd/next
SPI NOR core changes: - introduce 'struct spi_nor_controller_ops', - clean the Register Operations methods, - use dev_dbg insted of dev_err for low level info, - fix retlen handling in sst_write(), - fix silent truncations in spi_nor_read and spi_nor_read_raw(), - fix the clearing of QE bit on lock()/unlock(), - rework the disabling of the block write protection, - rework the Quad Enable methods, - make sure nor->spimem and nor->controller_ops are mutually exclusive, - set default Quad Enable method for ISSI flashes, - add support for few flashes. SPI NOR controller drivers changes: - intel-spi: - support chips without software sequencer, - add support for Intel Cannon Lake and Intel Comet Lake-H flashes.
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diff --git a/Documentation/arm64/memory.rst b/Documentation/arm64/memory.rst
index b040909e45f8..02e02175e6f5 100644
--- a/Documentation/arm64/memory.rst
+++ b/Documentation/arm64/memory.rst
@@ -154,11 +154,18 @@ return virtual addresses to userspace from a 48-bit range.
Software can "opt-in" to receiving VAs from a 52-bit space by
specifying an mmap hint parameter that is larger than 48-bit.
+
For example:
- maybe_high_address = mmap(~0UL, size, prot, flags,...);
+
+.. code-block:: c
+
+ maybe_high_address = mmap(~0UL, size, prot, flags,...);
It is also possible to build a debug kernel that returns addresses
from a 52-bit space by enabling the following kernel config options:
+
+.. code-block:: sh
+
CONFIG_EXPERT=y && CONFIG_ARM64_FORCE_52BIT=y
Note that this option is only intended for debugging applications
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