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

net: ipa: separate disabling setup from modem stop

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

[ Upstream commit 8afc7e471ad3c92a9c96adc62d1b67de77378bb6 ] The IPA setup_complete flag is set at the end of ipa_setup(), when the setup phase of initialization has completed successfully. This occurs as part of driver probe processing, or (if "modem-init" is specified in the DTS file) it is triggered by the "ipa-setup-ready" SMP2P interrupt generated by the modem. In the latter case, it's possible for driver shutdown (or remove) to begin while setup processing is underway, and this can't be allowed. The problem is that the setup_complete flag is not adequate to signal that setup is underway. If setup_complete is set, it will never be un-set, so that case is not a problem. But if setup_complete is false, there's a chance setup is underway. Because setup is triggered by an interrupt on a "modem-init" system, there is a simple way to ensure the value of setup_complete is safe to read. The threaded handler--if it is executing--will complete as part of a request to disable the "ipa-modem-ready" interrupt. This means that ipa_setup() (which is called from the handler) will run to completion if it was underway, or will never be called otherwise. The request to disable the "ipa-setup-ready" interrupt is currently made within ipa_modem_stop(). Instead, disable the interrupt outside that function in the two places it's called. In the case of ipa_remove(), this ensures the setup_complete flag is safe to read before we read it. Rename ipa_smp2p_disable() to be ipa_smp2p_irq_disable_setup(), to be more specific about its effect. Fixes: 530f9216a953 ("soc: qcom: ipa: AP/modem communications") 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 autosuspend

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

Use runtime power management autosuspend. Up until this point, we only suspended the IPA hardware for system suspend; now we'll suspend it aggressively using runtime power management, setting the initial autosuspend delay to half a second of inactivity. Replace pm_runtime_put() calls with pm_runtime_put_autosuspend(), call pm_runtime_mark_last_busy() before each of those. In places where we're shutting things down, or decrementing power references for errors, use pm_runtime_put_noidle() instead. Finally, remove ipa_runtime_idle(), so the ->runtime_suspend callback will occur if idle. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: don't use ipa_clock_get() in "ipa_main.c"

2021-08-20T13:45:47+00:00

We need the hardware to be powered starting at the config stage of initialization when the IPA driver probes. And we need it powered when the driver is removed, at least until the deconfig stage has completed. Replace callers of ipa_clock_get() in ipa_probe() and ipa_exit(), calling pm_runtime_get_sync() instead. Replace the corresponding callers of ipa_clock_put(), calling pm_runtime_put() instead. The only error we expect when getting power would occur when the system is suspended. The ->probe and ->remove driver callbacks won't be called when suspended, so issue a WARN() call if an error is seen getting power. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: enable wakeup in ipa_power_setup()

2021-08-14T13:13:38+00:00

Move the call to enable the IPA interrupt as a wakeup interrupt into ipa_power_setup(), disable it in ipa_power_teardown(). Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: always inline ipa_aggr_granularity_val()

2021-08-12T21:51:44+00:00

It isn't required, but all callers of ipa_aggr_granularity_val() pass a constant value (IPA_AGGR_GRANULARITY) as the usec argument. Two of those callers are in ipa_validate_build(), with the result being passed to BUILD_BUG_ON(). Evidently the "sparc64-linux-gcc" compiler (at least) doesn't always inline ipa_aggr_granularity_val(), so the result of the function is not constant at compile time, and that leads to build errors. Define the function with the __always_inline attribute to avoid the errors. We can see by inspection that the value passed is never zero, so we can just remove its WARN_ON() call. Fixes: 5bc5588466a1f ("net: ipa: use WARN_ON() rather than assertions") Reported-by: kernel test robot Signed-off-by: Alex Elder Link: https://lore.kernel.org/r/20210811135948.2634264-1-elder@linaro.org Signed-off-by: Jakub Kicinski

net: ipa: get rid of extra clock reference

2021-08-11T12:31:56+00:00

Suspending the IPA hardware is now managed by the runtime PM core code. The ->runtime_idle callback returns a non-zero value, so it will never suspend except when forced. As a result, there's no need to take an extra "do not suspend" clock reference. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: have ipa_clock_get() return a value

2021-08-11T12:31:55+00:00

We currently assume no errors occur when enabling or disabling the IPA core clock and interconnects. And although this commit exposes errors that could occur, we generally assume this won't happen in practice. This commit changes ipa_clock_get() and ipa_clock_put() so each returns a value. The values returned are meant to mimic what the runtime power management functions return, so we can set up error handling here before we make the switch. Have ipa_clock_get() increment the reference count even if it returns an error, to match the behavior of pm_runtime_get(). More details follow. When taking a reference in ipa_clock_get(), return 0 for the first reference, 1 for subsequent references, or a negative error code if an error occurs. Note that if ipa_clock_get() returns an error, we must not touch hardware; in some cases such errors now cause entire blocks of code to be skipped. When dropping a reference in ipa_clock_put(), we return 0 or an error code. The error would come from ipa_clock_disable(), which now returns what ipa_interconnect_disable() returns (either 0 or a negative error code). For now, callers ignore the return value; if an error occurs, a message will have already been logged, and little more can actually be done to improve the situation. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: move ipa_suspend_handler()

2021-08-05T10:27:05+00:00

Move ipa_suspend_handler() into "ipa_clock.c" from "ipa_main.c", to group with the reset of the suspend/resume code. This IPA interrupt is triggered if an IPA RX endpoint is suspended but has a packet to be delivered. Introduce ipa_power_setup() and ipa_power_teardown() to add and remove the handler for the IPA SUSPEND interrupt at the same place as before, while allowing the handler to remain private. The "power" naming convention will be adopted elsewhere in this file as well (soon). Signed-off-by: Alex Elder Signed-off-by: David S. Miller