kernel/linux.git/drivers/net/ipa/ipa_endpoint.c, branch v5.15.7

net: ipa: kill ipa_cmd_pipeline_clear()

2021-12-01T08:04:51+00:00

[ Upstream commit e4e9bfb7c93d7e78aa4ad7e1c411a8df15386062 ] Calling ipa_cmd_pipeline_clear() after stopping the channel underlying the AP<-modem RX endpoint can lead to a deadlock. This occurs in the ->runtime_suspend device power operation for the IPA driver. While this callback is in progress, any other requests for power will block until the callback returns. Stopping the AP<-modem RX channel does not prevent the modem from sending another packet to this endpoint. If a packet arrives for an RX channel when the channel is stopped, an SUSPEND IPA interrupt condition will be pending. Handling an IPA interrupt requires power, so ipa_isr_thread() calls pm_runtime_get_sync() first thing. The problem occurs because a "pipeline clear" command will not complete while such a SUSPEND interrupt condition exists. So the SUSPEND IPA interrupt handler won't proceed until it gets power; that won't happen until the ->runtime_suspend callback (and its "pipeline clear" command) completes; and that can't happen while the SUSPEND interrupt condition exists. It turns out that in this case there is no need to use the "pipeline clear" command. There are scenarios in which clearing the pipeline is required while suspending, but those are not (yet) supported upstream. So a simple fix, avoiding the potential deadlock, is to stop calling ipa_cmd_pipeline_clear() in ipa_endpoint_suspend(). This removes the only user of ipa_cmd_pipeline_clear(), so get rid of that function. It can be restored again whenever it's needed. This is basically a manual revert along with an explanation for commit 6cb63ea6a39ea ("net: ipa: introduce ipa_cmd_tag_process()"). Fixes: 6cb63ea6a39ea ("net: ipa: introduce ipa_cmd_tag_process()") Signed-off-by: Alex Elder Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: ipa: disable HOLB drop when updating timer

2021-11-25T08:48:34+00:00

[ Upstream commit 816316cacad2b5abd5b41423cf04e4845239abd4 ] The head-of-line blocking timer should only be modified when head-of-line drop is disabled. One of the steps in recovering from a modem crash is to enable dropping of packets with timeout of 0 (immediate). We don't know how the modem configured its endpoints, so before we program the timer, we need to ensure HOL_BLOCK is disabled. Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints") Signed-off-by: Alex Elder Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: ipa: HOLB register sometimes must be written twice

2021-11-25T08:48:34+00:00

[ Upstream commit 6e228d8cbb1cc6ba78022d406340e901e08d26e0 ] Starting with IPA v4.5, the HOL_BLOCK_EN register must be written twice when enabling head-of-line blocking avoidance. Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints") Signed-off-by: Alex Elder Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: ipa: rename "ipa_clock.c"

2021-08-22T08:44:17+00:00

Finally, rename "ipa_clock.c" to be "ipa_power.c" and "ipa_clock.h" to be "ipa_power.h". Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: rename ipa_clock_* symbols

2021-08-22T08:44:17+00:00

Rename a number of functions to clarify that there is no longer a notion of an "IPA clock," but rather that the functions are more generally related to IPA power management. ipa_clock_enable() -> ipa_power_enable() ipa_clock_disable() -> ipa_power_disable() ipa_clock_rate() -> ipa_core_clock_rate() ipa_clock_init() -> ipa_power_init() ipa_clock_exit() -> ipa_power_exit() Rename the ipa_clock structure to be ipa_power. Rename all variables and fields using that structure type "power" rather than "clock". Rename the ipa_clock_data structure to be ipa_power_data, and more broadly, just substitute "power" for "clock" in places that previously represented things related to the "IPA clock". Update comments throughout. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: use gsi->version for channel suspend/resume

2021-08-04T09:12:05+00:00

The GSI layer has the IPA version now, so there's no need for version-specific flags to be passed from IPA. One instance of this is in gsi_channel_suspend() and gsi_channel_resume(), which indicate whether or not the endpoint suspend is implemented by GSI stopping the channel. We can make that determination based on gsi->version, eliminating the need for a Boolean flag in those functions. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: use WARN_ON() rather than assertions

2021-07-26T21:38:11+00:00

I've added commented assertions to record certain properties that can be assumed to hold in certain places in the IPA code. Convert these into real WARN_ON() calls so the assertions are actually checked, using the standard WARN_ON() mechanism. Where errors can be returned, return an error if a warning is triggered. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: FLAVOR_0 register doesn't exist until IPA v3.5

2021-06-21T19:30:59+00:00

The FLAVOR_0 version first appears in IPA v3.5, so avoid attempting to read it for versions prior to that. This register contains a concise definition of the number and direction of endpoints supported by the hardware, and without it we can't verify endpoint configuration in ipa_endpoint_config(). In this case, just indicate that any endpoint number is available for use. Originally proposed by AngeloGioacchino Del Regno. Link: https://lore.kernel.org/netdev/20210211175015.200772-3-angelogioacchino.delregno@somainline.org Signed-off-by: Alex Elder Acked-by: AngeloGioacchino Del Regno Signed-off-by: David S. Miller

net: ipa: make endpoint data validation unconditional

2021-06-11T21:13:18+00:00

The cost of validating the endpoint configuration data is not all that high, so just do it unconditionally, rather than doing so only when IPA_VALIDATAION is defined. Suggested-by: Leon Romanovsky Signed-off-by: Alex Elder Signed-off-by: David S. Miller

Revert "net: ipa: disable checksum offload for IPA v4.5+"

2021-06-03T22:09:40+00:00

This reverts commit c88c34fcf8f501d588c0a999aa7e51e18552c5f0. The RMNet driver now supports inline checksum offload. Signed-off-by: Alex Elder Signed-off-by: David S. Miller