From: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
To: Linux Doc Mailing List <linux-doc@vger.kernel.org>
Cc: "Mauro Carvalho Chehab" <mchehab+samsung@kernel.org>,
"Mauro Carvalho Chehab" <mchehab@infradead.org>,
linux-kernel@vger.kernel.org, "Jonathan Corbet" <corbet@lwn.net>,
"Vladimir Oltean" <olteanv@gmail.com>,
"Mike Rapoport" <rppt@linux.vnet.ibm.com>,
"Andrew Morton" <akpm@linux-foundation.org>,
"Randy Dunlap" <rdunlap@infradead.org>,
"Matthew Wilcox" <willy@infradead.org>,
"Kent Overstreet" <kent.overstreet@gmail.com>,
"Arnd Bergmann" <arnd@arndb.de>,
"Jonathan Neuschäfer" <j.neuschaefer@gmx.net>,
"David S. Miller" <davem@davemloft.net>,
netdev@vger.kernel.org
Subject: [PATCH] docs: packing: move it to core-api book and adjust markups
Date: Sat, 29 Jun 2019 07:37:02 -0300 [thread overview]
Message-ID: <46cb79dbc4bbff3e5a4e77b548df1e92c105ed0f.1561804613.git.mchehab+samsung@kernel.org> (raw)
The packing.txt file was misplaced, as docs should be part of
a documentation book, and not at the root dir.
So, move it to the core-api directory and add to its index.
Also, ensure that the file will be properly parsed and the bitmap
ascii artwork will use a monotonic font.
Fixes: 554aae35007e ("lib: Add support for generic packing operations")
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
---
Documentation/core-api/index.rst | 1 +
.../{packing.txt => core-api/packing.rst} | 81 +++++++++++--------
2 files changed, 50 insertions(+), 32 deletions(-)
rename Documentation/{packing.txt => core-api/packing.rst} (61%)
diff --git a/Documentation/core-api/index.rst b/Documentation/core-api/index.rst
index d1e5b95bf86d..aebb16d7771f 100644
--- a/Documentation/core-api/index.rst
+++ b/Documentation/core-api/index.rst
@@ -25,6 +25,7 @@ Core utilities
librs
genalloc
errseq
+ packing
printk-formats
circular-buffers
generic-radix-tree
diff --git a/Documentation/packing.txt b/Documentation/core-api/packing.rst
similarity index 61%
rename from Documentation/packing.txt
rename to Documentation/core-api/packing.rst
index f830c98645f1..d8c341fe383e 100644
--- a/Documentation/packing.txt
+++ b/Documentation/core-api/packing.rst
@@ -30,6 +30,7 @@ The solution
------------
This API deals with 2 basic operations:
+
- Packing a CPU-usable number into a memory buffer (with hardware
constraints/quirks)
- Unpacking a memory buffer (which has hardware constraints/quirks)
@@ -49,10 +50,12 @@ What the examples show is where the logical bytes and bits sit.
1. Normally (no quirks), we would do it like this:
-63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
-7 6 5 4
-31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
-3 2 1 0
+::
+
+ 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
+ 7 6 5 4
+ 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
+ 3 2 1 0
That is, the MSByte (7) of the CPU-usable u64 sits at memory offset 0, and the
LSByte (0) of the u64 sits at memory offset 7.
@@ -63,10 +66,12 @@ comments as "logical" notation.
2. If QUIRK_MSB_ON_THE_RIGHT is set, we do it like this:
-56 57 58 59 60 61 62 63 48 49 50 51 52 53 54 55 40 41 42 43 44 45 46 47 32 33 34 35 36 37 38 39
-7 6 5 4
-24 25 26 27 28 29 30 31 16 17 18 19 20 21 22 23 8 9 10 11 12 13 14 15 0 1 2 3 4 5 6 7
-3 2 1 0
+::
+
+ 56 57 58 59 60 61 62 63 48 49 50 51 52 53 54 55 40 41 42 43 44 45 46 47 32 33 34 35 36 37 38 39
+ 7 6 5 4
+ 24 25 26 27 28 29 30 31 16 17 18 19 20 21 22 23 8 9 10 11 12 13 14 15 0 1 2 3 4 5 6 7
+ 3 2 1 0
That is, QUIRK_MSB_ON_THE_RIGHT does not affect byte positioning, but
inverts bit offsets inside a byte.
@@ -74,10 +79,12 @@ inverts bit offsets inside a byte.
3. If QUIRK_LITTLE_ENDIAN is set, we do it like this:
-39 38 37 36 35 34 33 32 47 46 45 44 43 42 41 40 55 54 53 52 51 50 49 48 63 62 61 60 59 58 57 56
-4 5 6 7
-7 6 5 4 3 2 1 0 15 14 13 12 11 10 9 8 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24
-0 1 2 3
+::
+
+ 39 38 37 36 35 34 33 32 47 46 45 44 43 42 41 40 55 54 53 52 51 50 49 48 63 62 61 60 59 58 57 56
+ 4 5 6 7
+ 7 6 5 4 3 2 1 0 15 14 13 12 11 10 9 8 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24
+ 0 1 2 3
Therefore, QUIRK_LITTLE_ENDIAN means that inside the memory region, every
byte from each 4-byte word is placed at its mirrored position compared to
@@ -86,18 +93,22 @@ the boundary of that word.
4. If QUIRK_MSB_ON_THE_RIGHT and QUIRK_LITTLE_ENDIAN are both set, we do it
like this:
-32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63
-4 5 6 7
-0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
-0 1 2 3
+::
+
+ 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63
+ 4 5 6 7
+ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
+ 0 1 2 3
5. If just QUIRK_LSW32_IS_FIRST is set, we do it like this:
-31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
-3 2 1 0
-63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
-7 6 5 4
+::
+
+ 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
+ 3 2 1 0
+ 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
+ 7 6 5 4
In this case the 8 byte memory region is interpreted as follows: first
4 bytes correspond to the least significant 4-byte word, next 4 bytes to
@@ -107,28 +118,34 @@ the more significant 4-byte word.
6. If QUIRK_LSW32_IS_FIRST and QUIRK_MSB_ON_THE_RIGHT are set, we do it like
this:
-24 25 26 27 28 29 30 31 16 17 18 19 20 21 22 23 8 9 10 11 12 13 14 15 0 1 2 3 4 5 6 7
-3 2 1 0
-56 57 58 59 60 61 62 63 48 49 50 51 52 53 54 55 40 41 42 43 44 45 46 47 32 33 34 35 36 37 38 39
-7 6 5 4
+::
+
+ 24 25 26 27 28 29 30 31 16 17 18 19 20 21 22 23 8 9 10 11 12 13 14 15 0 1 2 3 4 5 6 7
+ 3 2 1 0
+ 56 57 58 59 60 61 62 63 48 49 50 51 52 53 54 55 40 41 42 43 44 45 46 47 32 33 34 35 36 37 38 39
+ 7 6 5 4
7. If QUIRK_LSW32_IS_FIRST and QUIRK_LITTLE_ENDIAN are set, it looks like
this:
-7 6 5 4 3 2 1 0 15 14 13 12 11 10 9 8 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24
-0 1 2 3
-39 38 37 36 35 34 33 32 47 46 45 44 43 42 41 40 55 54 53 52 51 50 49 48 63 62 61 60 59 58 57 56
-4 5 6 7
+::
+
+ 7 6 5 4 3 2 1 0 15 14 13 12 11 10 9 8 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24
+ 0 1 2 3
+ 39 38 37 36 35 34 33 32 47 46 45 44 43 42 41 40 55 54 53 52 51 50 49 48 63 62 61 60 59 58 57 56
+ 4 5 6 7
8. If QUIRK_LSW32_IS_FIRST, QUIRK_LITTLE_ENDIAN and QUIRK_MSB_ON_THE_RIGHT
are set, it looks like this:
-0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
-0 1 2 3
-32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63
-4 5 6 7
+::
+
+ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
+ 0 1 2 3
+ 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63
+ 4 5 6 7
We always think of our offsets as if there were no quirk, and we translate
--
2.21.0
next reply other threads:[~2019-06-29 10:37 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-29 10:37 Mauro Carvalho Chehab [this message]
2019-06-29 10:42 ` [PATCH] docs: packing: move it to core-api book and adjust markups Mike Rapoport
2019-07-04 23:59 ` Vladimir Oltean
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=46cb79dbc4bbff3e5a4e77b548df1e92c105ed0f.1561804613.git.mchehab+samsung@kernel.org \
--to=mchehab+samsung@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=corbet@lwn.net \
--cc=davem@davemloft.net \
--cc=j.neuschaefer@gmx.net \
--cc=kent.overstreet@gmail.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mchehab@infradead.org \
--cc=netdev@vger.kernel.org \
--cc=olteanv@gmail.com \
--cc=rdunlap@infradead.org \
--cc=rppt@linux.vnet.ibm.com \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).