linux-stable.git/drivers/net/ipa/gsi.c, branch linux-6.2.y Linux kernel stable tree net: ipa: generic command param fix 2023-03-10T08:28:17+00:00 Alex Elder elder@linaro.org 2023-02-08T20:56:45+00:00 01fc68c867041072ff36a02dfd263d1a9a710721 [ Upstream commit 2df181f09c961377a55510a864216d48d787fe49 ] Starting at IPA v4.11, the GSI_GENERIC_COMMAND GSI register got a new PARAMS field. The code that encodes a value into that field sets it unconditionally, which is wrong. We currently only provide 0 as the field's value, so this error has no real effect. Still, it's a bug, so let's fix it. Fix an (unrelated) incorrect comment as well. Fields in the ERROR_LOG GSI register actually *are* defined for IPA versions prior to v3.5.1. Fixes: fe68c43ce388 ("net: ipa: support enhanced channel flow control") Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2df181f09c961377a55510a864216d48d787fe49 ]

Starting at IPA v4.11, the GSI_GENERIC_COMMAND GSI register got a
new PARAMS field.  The code that encodes a value into that field
sets it unconditionally, which is wrong.

We currently only provide 0 as the field's value, so this error has
no real effect.  Still, it's a bug, so let's fix it.

Fix an (unrelated) incorrect comment as well.  Fields in the
ERROR_LOG GSI register actually *are* defined for IPA versions
prior to v3.5.1.

Fixes: fe68c43ce388 ("net: ipa: support enhanced channel flow control")
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: ipa: update copyrights 2022-10-03T23:49:20+00:00 Alex Elder elder@linaro.org 2022-09-30T22:45:49+00:00 a4388da51ad56366d330144975e50f162a10bd8b Some source files state copyright dates that are earlier than the last modification of the file. Change the copyright year to 2022 in all such cases. Signed-off-by: Alex Elder <elder@linaro.org> Link: https://lore.kernel.org/r/20220930224549.3503434-1-elder@linaro.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Some source files state copyright dates that are earlier than the
last modification of the file.  Change the copyright year to 2022 in
all such cases.

Signed-off-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20220930224549.3503434-1-elder@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: ipa: update comments 2022-10-03T23:49:05+00:00 Alex Elder elder@linaro.org 2022-09-30T22:45:27+00:00 ace5dc61620ba1592bf9e24da4c290a357830b8c This patch just updates comments throughout the IPA code. Transaction state is now tracked using indexes into an array rather than linked lists, and a few comments refer to the "old way" of doing things. The description of how transactions are used was changed to refer to "operations" rather than "commands", to (hopefully) remove a possible ambiguity. IPA register offsets and fields are now handled differently as well, and the register documentation is updated to better describe the code. A few minor updates to comments were made (e.g., adding a missing word, fixing a typo or punctuation, etc.). Finally, the local macro atomic_dec_not_zero() is no longer used, so it is deleted. Signed-off-by: Alex Elder <elder@linaro.org> Link: https://lore.kernel.org/r/20220930224527.3503404-1-elder@linaro.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
This patch just updates comments throughout the IPA code.

Transaction state is now tracked using indexes into an array rather
than linked lists, and a few comments refer to the "old way" of
doing things.  The description of how transactions are used was
changed to refer to "operations" rather than "commands", to
(hopefully) remove a possible ambiguity.

IPA register offsets and fields are now handled differently as well,
and the register documentation is updated to better describe the
code.

A few minor updates to comments were made (e.g., adding a missing
word, fixing a typo or punctuation, etc.).

Finally, the local macro atomic_dec_not_zero() is no longer used, so
it is deleted.

Signed-off-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20220930224527.3503404-1-elder@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: drop the weight argument from netif_napi_add 2022-09-29T01:57:14+00:00 Jakub Kicinski kuba@kernel.org 2022-09-27T13:27:53+00:00 b48b89f9c189d24eb5e2b4a0ac067da5a24ee86d We tell driver developers to always pass NAPI_POLL_WEIGHT as the weight to netif_napi_add(). This may be confusing to newcomers, drop the weight argument, those who really need to tweak the weight can use netif_napi_add_weight(). Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for CAN Link: https://lore.kernel.org/r/20220927132753.750069-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
We tell driver developers to always pass NAPI_POLL_WEIGHT
as the weight to netif_napi_add(). This may be confusing
to newcomers, drop the weight argument, those who really
need to tweak the weight can use netif_napi_add_weight().

Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for CAN
Link: https://lore.kernel.org/r/20220927132753.750069-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: ipa: don't have gsi_channel_update() return a value 2022-09-09T10:45:25+00:00 Alex Elder elder@linaro.org 2022-09-06T17:19:42+00:00 019e37eaef97d99285390b6eb42410a54a5d6412 If it finds no completed transactions, gsi_channel_trans_complete() calls gsi_channel_update() to check hardware. If new transactions have completed, gsi_channel_update() records that, then calls gsi_channel_trans_complete() to return the first of those found. This recursion won't go any further, but can be avoided if we have gsi_channel_update() only be responsible for updating state after accessing hardware. Change gsi_channel_update() so it simply checks for and handles new completions, without returning a value. If it needs to call that function, have gsi_channel_trans_complete() determine whether there are new transactions available after the update. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
If it finds no completed transactions, gsi_channel_trans_complete()
calls gsi_channel_update() to check hardware.  If new transactions
have completed, gsi_channel_update() records that, then calls
gsi_channel_trans_complete() to return the first of those found.
This recursion won't go any further, but can be avoided if we
have gsi_channel_update() only be responsible for updating state
after accessing hardware.

Change gsi_channel_update() so it simply checks for and handles
new completions, without returning a value.  If it needs to call
that function, have gsi_channel_trans_complete() determine whether
there are new transactions available after the update.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: ipa: update channel in gsi_channel_trans_complete() 2022-09-09T10:45:25+00:00 Alex Elder elder@linaro.org 2022-09-06T17:19:41+00:00 e0e3406c60d7e5b004cc3059dea6c7574d26ca66 Have gsi_channel_trans_complete() update the known state from hardware rather than doing so in gsi_channel_poll_one(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Have gsi_channel_trans_complete() update the known state from
hardware rather than doing so in gsi_channel_poll_one().

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: ipa: further simplify gsi_channel_trans_last() 2022-09-05T11:47:02+00:00 Alex Elder elder@linaro.org 2022-09-02T21:02:17+00:00 4601e75596cb7a4d538e7b9cf0b599b364acbae8 Do a little more refactoring in gsi_channel_trans_last() to simplify it further. The resulting code should behave exactly as before. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Do a little more refactoring in gsi_channel_trans_last() to simplify
it further.  The resulting code should behave exactly as before.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: ipa: simplify gsi_channel_trans_last() 2022-09-05T11:47:02+00:00 Alex Elder elder@linaro.org 2022-09-02T21:02:16+00:00 e68d1d1591fd70de0651e1af66db69540f556e73 Using a little logic we can simplify gsi_channel_trans_last(). The first condition in that function looks like this: if (trans_info->allocated_id != trans_info->free_id) And if that's false, we proceed to the next one: if (trans_info->committed_id != trans_info->allocated_id) Failure of the first test implies: trans_info->allocated_id == trans_info->free_id And therefore, the second one can be rewritten this way: if (trans_info->committed_id != trans_info->free_id) Substituting free_id for allocated_id and committed_id can also be done in the code blocks executed when these conditions yield true. The net result is that all three blocks for TX endpoints can be consolidated into just one. The two blocks of code at the end of that function (used for both TX and RX channels) can be similarly consolidated into a single block. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Using a little logic we can simplify gsi_channel_trans_last().

The first condition in that function looks like this:
    if (trans_info->allocated_id != trans_info->free_id)
And if that's false, we proceed to the next one:
    if (trans_info->committed_id != trans_info->allocated_id)

Failure of the first test implies:
    trans_info->allocated_id == trans_info->free_id
And therefore, the second one can be rewritten this way:
    if (trans_info->committed_id != trans_info->free_id)

Substituting free_id for allocated_id and committed_id can also be
done in the code blocks executed when these conditions yield true.
The net result is that all three blocks for TX endpoints can be
consolidated into just one.

The two blocks of code at the end of that function (used for both TX
and RX channels) can be similarly consolidated into a single block.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: ipa: use IDs exclusively for last transaction 2022-09-05T11:47:01+00:00 Alex Elder elder@linaro.org 2022-09-02T21:02:15+00:00 897c0ce665d619227e19f59934115c1b7719621f Always use transaction IDs when finding the "last" transaction to await when quiescing a channel. This basically extends what was done in the previous patch to all other transaction state IDs. As a result we are no longer updating any transaction lists inside gsi_channel_trans_last(), so there's no need to take the spinlock. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Always use transaction IDs when finding the "last" transaction to
await when quiescing a channel.  This basically extends what was
done in the previous patch to all other transaction state IDs.

As a result we are no longer updating any transaction lists inside
gsi_channel_trans_last(), so there's no need to take the spinlock.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: ipa: use IDs for last allocated transaction 2022-09-05T11:47:01+00:00 Alex Elder elder@linaro.org 2022-09-02T21:02:14+00:00 c30623ea0b3a9d766f34f75a326b8c610ca3105e Use the allocated and free transaction IDs to determine whether the "last" transaction used for quiescing a channel is in allocated state. The last allocated transaction that has not been committed (if any) immediately precedes the first free transaction in the transaction array. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Use the allocated and free transaction IDs to determine whether the
"last" transaction used for quiescing a channel is in allocated
state.  The last allocated transaction that has not been committed
(if any) immediately precedes the first free transaction in the
transaction array.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>