docs: networking: device drivers: convert toshiba/spider_net.txt to ReST

- add SPDX header;
- adjust title markup;
- mark code blocks and literals as such;
- adjust identation, whitespaces and blank lines where needed;
- add to networking/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Mauro Carvalho Chehab 2020-05-01 16:44:57 +02:00 committed by David S. Miller
parent e9a5475e73
commit 7ac0cbb491
3 changed files with 30 additions and 31 deletions

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@ -50,6 +50,7 @@ Contents:
ti/cpsw_switchdev
ti/cpsw
ti/tlan
toshiba/spider_net
.. only:: subproject and html

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@ -1,6 +1,8 @@
.. SPDX-License-Identifier: GPL-2.0
The Spidernet Device Driver
===========================
===========================
The Spidernet Device Driver
===========================
Written by Linas Vepstas <linas@austin.ibm.com>
@ -78,15 +80,15 @@ GDACTDPA, tail and head pointers. It will also summarize the contents
of the ring, starting at the tail pointer, and listing the status
of the descrs that follow.
A typical example of the output, for a nearly idle system, might be
A typical example of the output, for a nearly idle system, might be::
net eth1: Total number of descrs=256
net eth1: Chain tail located at descr=20
net eth1: Chain head is at 20
net eth1: HW curr desc (GDACTDPA) is at 21
net eth1: Have 1 descrs with stat=x40800101
net eth1: HW next desc (GDACNEXTDA) is at 22
net eth1: Last 255 descrs with stat=xa0800000
net eth1: Total number of descrs=256
net eth1: Chain tail located at descr=20
net eth1: Chain head is at 20
net eth1: HW curr desc (GDACTDPA) is at 21
net eth1: Have 1 descrs with stat=x40800101
net eth1: HW next desc (GDACNEXTDA) is at 22
net eth1: Last 255 descrs with stat=xa0800000
In the above, the hardware has filled in one descr, number 20. Both
head and tail are pointing at 20, because it has not yet been emptied.
@ -101,11 +103,11 @@ The status x4... corresponds to "full" and status xa... corresponds
to "empty". The actual value printed is RXCOMST_A.
In the device driver source code, a different set of names are
used for these same concepts, so that
used for these same concepts, so that::
"empty" == SPIDER_NET_DESCR_CARDOWNED == 0xa
"full" == SPIDER_NET_DESCR_FRAME_END == 0x4
"not in use" == SPIDER_NET_DESCR_NOT_IN_USE == 0xf
"empty" == SPIDER_NET_DESCR_CARDOWNED == 0xa
"full" == SPIDER_NET_DESCR_FRAME_END == 0x4
"not in use" == SPIDER_NET_DESCR_NOT_IN_USE == 0xf
The RX RAM full bug/feature
@ -137,19 +139,19 @@ while the hardware is waiting for a different set of descrs to become
empty.
A call to show_rx_chain() at this point indicates the nature of the
problem. A typical print when the network is hung shows the following:
problem. A typical print when the network is hung shows the following::
net eth1: Spider RX RAM full, incoming packets might be discarded!
net eth1: Total number of descrs=256
net eth1: Chain tail located at descr=255
net eth1: Chain head is at 255
net eth1: HW curr desc (GDACTDPA) is at 0
net eth1: Have 1 descrs with stat=xa0800000
net eth1: HW next desc (GDACNEXTDA) is at 1
net eth1: Have 127 descrs with stat=x40800101
net eth1: Have 1 descrs with stat=x40800001
net eth1: Have 126 descrs with stat=x40800101
net eth1: Last 1 descrs with stat=xa0800000
net eth1: Spider RX RAM full, incoming packets might be discarded!
net eth1: Total number of descrs=256
net eth1: Chain tail located at descr=255
net eth1: Chain head is at 255
net eth1: HW curr desc (GDACTDPA) is at 0
net eth1: Have 1 descrs with stat=xa0800000
net eth1: HW next desc (GDACNEXTDA) is at 1
net eth1: Have 127 descrs with stat=x40800101
net eth1: Have 1 descrs with stat=x40800001
net eth1: Have 126 descrs with stat=x40800101
net eth1: Last 1 descrs with stat=xa0800000
Both the tail and head pointers are pointing at descr 255, which is
marked xa... which is "empty". Thus, from the OS point of view, there
@ -198,7 +200,3 @@ For large packets, this mechanism generates a relatively small number
of interrupts, about 1K/sec. For smaller packets, this will drop to zero
interrupts, as the hardware can empty the queue faster than the kernel
can fill it.
======= END OF DOCUMENT ========

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@ -15874,7 +15874,7 @@ SPIDERNET NETWORK DRIVER for CELL
M: Ishizaki Kou <kou.ishizaki@toshiba.co.jp>
L: netdev@vger.kernel.org
S: Supported
F: Documentation/networking/device_drivers/toshiba/spider_net.txt
F: Documentation/networking/device_drivers/toshiba/spider_net.rst
F: drivers/net/ethernet/toshiba/spider_net*
SPMI SUBSYSTEM