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path: root/drivers/net/ipa
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2021-11-23net: ipa: kill ipa_cmd_pipeline_clear()Alex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-23net: ipa: separate disabling setup from modem stopAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-23net: ipa: directly disable ipa-setup-ready interruptAlex Elder
We currently maintain a "disabled" Boolean flag to determine whether the "ipa-setup-ready" SMP2P IRQ handler does anything. That flag must be accessed under protection of a mutex. Instead, disable the SMP2P interrupt when requested, which prevents the interrupt handler from ever being called. More importantly, it synchronizes a thread disabling the interrupt with the completion of the interrupt handler in case they run concurrently. Use the IPA setup_complete flag rather than the disabled flag in the handler to determine whether to ignore any interrupts arriving after the first. Rename the "disabled" flag to be "setup_disabled", to be specific about its purpose. Fixes: 530f9216a953 ("soc: qcom: ipa: AP/modem communications") Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-15net: ipa: disable HOLB drop when updating timerAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-15net: ipa: HOLB register sometimes must be written twiceAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-12net/ipa: ipa_resource: Fix wrong for loop rangeKonrad Dybcio
The source group count was mistakenly assigned to both dst and src loops. Fix it to make IPA probe and work again. Fixes: 4fd704b3608a ("net: ipa: record number of groups in data") Acked-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org> Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org> Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org> Reviewed-by: Alex Elder <elder@linaro.org> Link: https://lore.kernel.org/r/20211111183724.593478-1-konrad.dybcio@somainline.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-08Merge tag 'asm-generic-fixes-5.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic fixes from Arnd Bergmann: "There is one build fix for Arm platforms that ended up impacting most architectures because of the way the drivers/firmware Kconfig file is wired up: The CONFIG_QCOM_SCM dependency have caused a number of randconfig regressions over time, and some still remain in v5.15-rc4. The fix we agreed on in the end is to make this symbol selected by any driver using it, and then building it even for non-Arm platforms with CONFIG_COMPILE_TEST. To make this work on all architectures, the drivers/firmware/Kconfig file needs to be included for all architectures to make the symbol itself visible. In a separate discussion, we found that a sound driver patch that is pending for v5.16 needs the same change to include this Kconfig file, so the easiest solution seems to have my Kconfig rework included in v5.15. Finally, the branch also includes a small unrelated build fix for NOMMU architectures" Link: https://lore.kernel.org/all/20210928153508.101208f8@canb.auug.org.au/ Link: https://lore.kernel.org/all/20210928075216.4193128-1-arnd@kernel.org/ Link: https://lore.kernel.org/all/20211007151010.333516-1-arnd@kernel.org/ * tag 'asm-generic-fixes-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic/io.h: give stub iounmap() on !MMU same prototype as elsewhere qcom_scm: hide Kconfig symbol firmware: include drivers/firmware/Kconfig unconditionally
2021-10-07qcom_scm: hide Kconfig symbolArnd Bergmann
Now that SCM can be a loadable module, we have to add another dependency to avoid link failures when ipa or adreno-gpu are built-in: aarch64-linux-ld: drivers/net/ipa/ipa_main.o: in function `ipa_probe': ipa_main.c:(.text+0xfc4): undefined reference to `qcom_scm_is_available' ld.lld: error: undefined symbol: qcom_scm_is_available >>> referenced by adreno_gpu.c >>> gpu/drm/msm/adreno/adreno_gpu.o:(adreno_zap_shader_load) in archive drivers/built-in.a This can happen when CONFIG_ARCH_QCOM is disabled and we don't select QCOM_MDT_LOADER, but some other module selects QCOM_SCM. Ideally we'd use a similar dependency here to what we have for QCOM_RPROC_COMMON, but that causes dependency loops from other things selecting QCOM_SCM. This appears to be an endless problem, so try something different this time: - CONFIG_QCOM_SCM becomes a hidden symbol that nothing 'depends on' but that is simply selected by all of its users - All the stubs in include/linux/qcom_scm.h can go away - arm-smccc.h needs to provide a stub for __arm_smccc_smc() to allow compile-testing QCOM_SCM on all architectures. - To avoid a circular dependency chain involving RESET_CONTROLLER and PINCTRL_SUNXI, drop the 'select RESET_CONTROLLER' statement. According to my testing this still builds fine, and the QCOM platform selects this symbol already. Acked-by: Kalle Valo <kvalo@codeaurora.org> Acked-by: Alex Elder <elder@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2021-09-08net: ipa: initialize all filter table slotsAlex Elder
There is an off-by-one problem in ipa_table_init_add(), when initializing filter tables. In that function, the number of filter table entries is determined based on the number of set bits in the filter map. However that count does *not* include the extra "slot" in the filter table that holds the filter map itself. Meanwhile, ipa_table_addr() *does* include the filter map in the memory it returns, but because the count it's provided doesn't include it, it includes one too few table entries. Fix this by including the extra slot for the filter map in the count computed in ipa_table_init_add(). Note: ipa_filter_reset_table() does not have this problem; it resets filter table entries one by one, but does not overwrite the filter bitmap. Fixes: 2b9feef2b6c2 ("soc: qcom: ipa: filter and routing tables") Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-22net: ipa: rename "ipa_clock.c"Alex Elder
Finally, rename "ipa_clock.c" to be "ipa_power.c" and "ipa_clock.h" to be "ipa_power.h". Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-22net: ipa: rename ipa_clock_* symbolsAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-22net: ipa: use autosuspendAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-20net: ipa: kill ipa_clock_get()Alex Elder
The only remaining user of the ipa_clock_{get,put}() interface is ipa_isr_thread(). Replace calls to ipa_clock_get() there calling pm_runtime_get_sync() instead. And call pm_runtime_put() there rather than ipa_clock_put(). Warn if we ever get an error. With that, we can get rid of ipa_clock_get() and ipa_clock_put(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-20net: ipa: don't use ipa_clock_get() in "ipa_modem.c"Alex Elder
When we open or close the modem network device we need to ensure the hardware is powered. Replace the callers of ipa_clock_get() found in ipa_open() and ipa_stop() with calls to pm_runtime_get_sync(). If an error is returned, simply return that error to the caller (without any error or warning message). This could conceivably occur if the function was called while the system was suspended, but that really shouldn't happen. Replace corresponding calls to ipa_clock_put() with pm_runtime_put() also. If the modem crashes we also need to ensure the hardware is powered to recover. If getting power returns an error there's not much we can do, but at least report the error. (Ideally the remoteproc SSR code would ensure the AP was not suspended when it sends the notification, but that is not (yet) the case.) Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-20net: ipa: don't use ipa_clock_get() in "ipa_uc.c"Alex Elder
Replace the ipa_clock_get() call in ipa_uc_clock() when taking the "proxy" clock reference for the microcontroller with a call to pm_runtime_get_sync(). Replace calls of ipa_clock_put() for the microcontroller with pm_runtime_put() calls instead. There is a chance we get an error when taking the microcontroller power reference. This is an unlikely scenario, where system suspend is initiated just before we learn the modem is booting. For now we'll just accept that this could occur, and report it if it does. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-20net: ipa: don't use ipa_clock_get() in "ipa_smp2p.c"Alex Elder
If the "modem-init" Device Tree property is present for a platform, the modem performs early IPA hardware initialization, and signals this is complete with an "ipa-setup-ready" SMP2P interrupt. This triggers a call to ipa_setup(), which requires the hardware to be powered. Replace the call to ipa_clock_get() in this case with a call to pm_runtime_get_sync(). And replace the corresponding calls to ipa_clock_put() with calls to pm_runtime_put() instead. There is a chance we get an error when taking this power reference. This is an unlikely scenario, where system suspend is initiated just before the modem signals it has finished initializing the IPA hardware. For now we'll just accept that this could occur, and report it if it does. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-20net: ipa: don't use ipa_clock_get() in "ipa_main.c"Alex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-20net: ipa: fix TX queue raceAlex Elder
Jakub Kicinski pointed out a race condition in ipa_start_xmit() in a recently-accepted series of patches: https://lore.kernel.org/netdev/20210812195035.2816276-1-elder@linaro.org/ We are stopping the modem TX queue in that function if the power state is not active. We restart the TX queue again once hardware resume is complete. TX path Power Management ------- ---------------- pm_runtime_get(); no power Start resume Stop TX queue ... pm_runtime_put() Resume complete return NETDEV_TX_BUSY Start TX queue pm_runtime_get() Power present, transmit pm_runtime_put() (auto-suspend) The issue is that the power management (resume) activity and the network transmit activity can occur concurrently, and there's a chance the queue will be stopped *after* it has been started again. TX path Power Management ------- ---------------- Resume underway pm_runtime_get(); no power ... Resume complete Start TX queue Stop TX queue <-- No more transmits after this pm_runtime_put() return NETDEV_TX_BUSY We address this using a STARTED flag to indicate when the TX queue has been started from the resume path, and a spinlock to make the flag and queue updates happen atomically. TX path Power Management ------- ---------------- Resume underway pm_runtime_get(); no power Resume complete start TX queue \ If STARTED flag is *not* set: > atomic Stop TX queue set STARTED flag / pm_runtime_put() return NETDEV_TX_BUSY A second flag is used to address a different race that involves another path requesting power. TX path Other path Power Management ------- ---------- ---------------- pm_runtime_get_sync() Resume Start TX queue \ atomic Set STARTED flag / (do its thing) pm_runtime_put() (auto-suspend) pm_runtime_get() Mark delayed resume STARTED *is* set, so do *not* stop TX queue <-- Queue should be stopped here pm_runtime_put() return NETDEV_TX_BUSY Suspend done, resume Resume complete pm_runtime_get() Stop TX queue (STARTED is *not* set) Start TX queue \ atomic pm_runtime_put() Set STARTED flag / return NETDEV_TX_BUSY So a STOPPED flag is set in the transmit path when it has stopped the TX queue, and this pair of operations is also protected by the spinlock. The resume path only restarts the TX queue if the STOPPED flag is set. This case isn't a major problem, but it avoids the "non-trivial amount of useless work" done by the networking stack when NETDEV_TX_BUSY is returned. Fixes: 6b51f802d652b ("net: ipa: ensure hardware has power in ipa_start_xmit()") Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-14net: ipa: don't hold clock reference while netdev openAlex Elder
Currently a clock reference is taken whenever the ->ndo_open callback for the modem netdev is called. That reference is dropped when the device is closed, in ipa_stop(). We no longer need this, because ipa_start_xmit() now handles the situation where the hardware power state is not active. Drop the clock reference in ipa_open() when we're done, and take a new reference in ipa_stop() before we begin closing the interface. Finally (and unrelated, but trivial), change the return type of ipa_start_xmit() to be netdev_tx_t instead of int. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-14net: ipa: don't stop TX on suspendAlex Elder
Currently we stop the modem netdev transmit queue when suspending the hardware. For system suspend this ensured we'd never attempt to transmit while attempting to suspend the modem endpoints. For runtime suspend, the IPA hardware might get suspended while the system is operating. In that case we want an attempt to transmit a packet to cause the hardware to resume if necessary. But if we disable the queue this cannot happen. So stop disabling the queue on suspend. In case we end up disabling it in ipa_start_xmit() (see the previous commit), we still arrange to start the TX queue on resume. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-14net: ipa: ensure hardware has power in ipa_start_xmit()Alex Elder
We need to ensure the hardware is powered when we transmit a packet. But if it's not, we can't block to wait for it. So asynchronously request power in ipa_start_xmit(), and only proceed if the return value indicates the power state is active. If the hardware is not active, a runtime resume request will have been initiated. In that case, stop the network stack from further transmit attempts until the resume completes. Return NETDEV_TX_BUSY, to retry sending the packet once the queue is restarted. If the power request returns an error (other than -EINPROGRESS, which just means a resume requested elsewhere isn't complete), just drop the packet. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-14net: ipa: re-enable transmit in PM WQ contextAlex Elder
Create a new work structure in the modem private data, and use it to re-enable the modem network device transmit queue when resuming. This is needed by the next patch, which stops the TX queue if IPA power isn't active when a transmit request arrives. Packets will start arriving the instant the TX queue is enabled, but resuming isn't complete until ipa_modem_resume() returns. This way we're sure to be resumed before transmits are allowed again. Cancel it before calling ipa_stop() in ipa_modem_stop() to ensure the transmit queue restart completes before it gets stopped there. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-14net: ipa: distinguish system from runtime suspendAlex Elder
Add a new flag that is set when the hardware is suspended due to a system suspend operation, distingishing it from runtime suspend. Use it in the SUSPEND IPA interrupt handler to determine whether to trigger a system resume because of the event. Define new suspend and resume power management callback functions to set and clear the new flag, respectively. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-14net: ipa: enable wakeup in ipa_power_setup()Alex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-12net: ipa: always inline ipa_aggr_granularity_val()Alex Elder
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 <lkp@intel.com> Signed-off-by: Alex Elder <elder@linaro.org> Link: https://lore.kernel.org/r/20210811135948.2634264-1-elder@linaro.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-11net: ipa: kill ipa_clock_get_additional()Alex Elder
Now that ipa_clock_get_additional() is a trivial wrapper around pm_runtime_get_if_active(), just open-code it in its only caller and delete the function. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: ipa: kill IPA clock reference countAlex Elder
The runtime power management core code maintains a usage count. This count mirrors the IPA clock reference count, and there's no need to maintain both. So get rid of the IPA clock reference count and just rely on the runtime PM usage count to determine when the hardware should be suspended or resumed. Use pm_runtime_get_if_active() in ipa_clock_get_additional(). We care whether power is active, regardless of whether it's in use, so pass true for its ign_usage_count argument. The IPA clock mutex is just used to make enabling/disabling the clock and updating the reference count occur atomically. Without the reference count, there's no need for the mutex, so get rid of that too. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: ipa: get rid of extra clock referenceAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: ipa: use runtime PM coreAlex Elder
Use the runtime power management core to cause hardware suspend and resume to occur. Enable it in ipa_clock_init() (without autosuspend), and disable it in ipa_clock_exit(). Use ipa_runtime_suspend() as the ->runtime_suspend power operation, and arrange for it to be called by having ipa_clock_get() call pm_runtime_get_sync() when the first clock reference is taken. Similarly, use ipa_runtime_resume() as the ->runtime_resume power operation, and pm_runtime_put() when the last IPA clock reference is dropped. Introduce ipa_runtime_idle() as the ->runtime_idle power operation, and have it return a non-zero value; this way suspend will never occur except when forced. Use pm_runtime_force_suspend() and pm_runtime_force_resume() as the system suspend and resume callbacks, and remove ipa_suspend() and ipa_resume(). Store a pointer to the device structure passed to ipa_clock_init(), so it can be used by ipa_clock_exit() to disable runtime power management. For now we preserve IPA clock reference counting. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: ipa: resume in ipa_clock_get()Alex Elder
Introduce ipa_runtime_suspend() and ipa_runtime_resume(), which encapsulate the activities necessary for suspending and resuming the IPA hardware. Call these functions from ipa_clock_get() and ipa_clock_put() when the first reference is taken or last one is dropped. When the very first clock reference is taken (for ipa_config()), setup isn't complete yet, so (as before) only the core clock gets enabled. When the last clock reference is dropped (after ipa_deconfig()), ipa_teardown() will have made the setup_complete flag false, so there too, the core clock will be stopped without affecting GSI or the endpoints. Otherwise these new functions will perform the desired suspend and resume actions once setup is complete. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: ipa: disable clock in suspendAlex Elder
Disable the IPA clock rather than dropping a reference to it in the system suspend callback. This forces the suspend to occur without affecting existing references. Similarly, enable the clock rather than taking a reference in ipa_resume(), forcing a resume without changing the reference count. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: ipa: have ipa_clock_get() return a valueAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: ipa: move IPA flags fieldAlex Elder
The ipa->flags field is only ever used in "ipa_clock.c", related to suspend/resume activity. Move the definition of the ipa_flag enumerated type to "ipa_clock.c". And move the flags field from the ipa structure and to the ipa_clock structure. Rename the type and its values to include "power" or "POWER" in the name. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: ipa: move ipa_suspend_handler()Alex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: ipa: move IPA power operations to ipa_clock.cAlex Elder
Move ipa_suspend() and ipa_resume(), as well as the definition of the ipa_pm_ops structure into "ipa_clock.c". Make ipa_pm_ops public and declare it as extern in "ipa_clock.h". This is part of centralizing IPA power management functionality into "ipa_clock.c" (the file will eventually get a name change). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: ipa: improve IPA clock error messagesAlex Elder
Rearrange messages reported when errors occur in the IPA clock code, so that the specific interconnect is identified when an error occurs enabling or disabling it, or the core clock is indicated when an error occurs enabling it. Have ipa_interconnect_disable() return zero or the negative error value returned by the first interconnect that produced an error when disabled. For now, the callers ignore the returned value. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: ipa: reorder netdev pointer assignmentsAlex Elder
Assign the ipa->modem_netdev and endpoint->netdev pointers *before* registering the network device. As soon as the device is registered it can be opened, and by that time we'll want those pointers valid. Similarly, don't make those pointers NULL until *after* the modem network device is unregistered in ipa_modem_stop(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: ipa: don't suspend/resume modem if not upAlex Elder
The modem network device is set up by ipa_modem_start(). But its TX queue is not actually started and endpoints enabled until it is opened. So avoid stopping the modem network device TX queue and disabling endpoints on suspend or stop unless the netdev is marked UP. And skip attempting to resume unless it is UP. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: ipa: fix IPA v4.9 interconnectsAlex Elder
Three interconnects are defined for IPA version 4.9, but there should only be two. They should also use names that match what's used for other platforms (and specified in the Device Tree binding). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: ipa: disable GSI interrupts while suspendedAlex Elder
Introduce new functions gsi_suspend() and gsi_resume(), which will disable the GSI interrupt handler after all endpoints are suspended and re-enable it before endpoints are resumed. This will ensure no GSI interrupt handler will fire when the hardware is suspended. Here's a little further explanation. There are seven GSI interrupt types, and most are disabled except when needed. - These two are not used (never enabled): GSI_INTER_EE_CH_CTRL GSI_INTER_EE_EV_CTRL - These two are only used to implement channel and event ring commands, and are only enabled while a command is underway: GSI_CH_CTRL GSI_EV_CTRL - The IEOB interrupt signals I/O completion. It will not fire when a channel is stopped (or "suspended"). GSI_IEOB - This interrupt is used to allocate or halt modem channels, and is only enabled while such a command is underway. GSI_GLOB_EE However it also is used to signal certain errors, and this could occur at any time. - The general interrupt signals general errors, and could occur at any time. GSI_GENERAL The purpose for this change is to ensure no global or general interrupts fire due to errors while the hardware is suspended. We enable the clock on resume, and at that time we can "handle" (at least report) these error conditions. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: ipa: move gsi_irq_init() code into setupAlex Elder
The GSI IRQ handler could be triggered as soon as it is registered with request_irq(). The handler function, gsi_isr(), touches hardware, meaning the IPA clock must be operational. The IPA clock is not operating when the handler is registered (in gsi_irq_init()), so this is a problem. Move the call to request_irq() for the GSI interrupt handler into gsi_irq_setup(), which is called when the IPA clock is known to be operational (and furthermore, the GSI firmware will have been loaded). Request the IRQ at the end of that function, after all interrupt types have been disabled and masked. Move the matching free_irq() call into gsi_irq_teardown(), and get rid of the now empty gsi_irq_exit(), Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: ipa: have gsi_irq_setup() return an error codeAlex Elder
Change gsi_irq_setup() so it returns an error value, and introduce gsi_irq_teardown() as its inverse. Set the interrupt type (IRQ rather than MSI) in gsi_irq_setup(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: ipa: move some GSI setup functionsAlex Elder
Move gsi_irq_setup() and gsi_ring_setup() so they're defined right above gsi_setup() where they're called. This is a trivial movement of code to prepare for upcoming patches. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: ipa: move version check for channel suspend/resumeAlex Elder
Change the Boolean flags passed to __gsi_channel_start() and __gsi_channel_stop() so they represent whether the request is being made to implement suspend (versus stop) or resume (versus start). Then stop or start the channel for suspend/resume requests only if the hardware version indicates it should be done. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: ipa: use gsi->version for channel suspend/resumeAlex Elder
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 <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-28net: ipa: don't suspend endpoints if setup not completeAlex Elder
Until we complete the setup stage of initialization, GSI is not initialized and therefore endpoints aren't usable. So avoid suspending endpoints during system suspend unless setup is complete. Clear the setup_complete flag at the top of ipa_teardown() to reflect the fact that things are no longer in setup state. Get rid of a misplaced (and superfluous) comment. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-28net: ipa: add a clock reference for netdev operationsAlex Elder
The IPA network device can be opened at any time, and an opened network device can be stopped any time. Both of these callback functions require access to the hardware, and therefore they need the IPA clock to be operational. Take an IPA clock reference in both the ->open and ->stop callback functions, dropping the reference when they are done accessing hardware. The ->start_xmit callback requires a little different handling, and that will be added separately. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-28net: ipa: add clock reference for remoteproc SSRAlex Elder
The remoteproc SSR callback function for the modem requires hardware access when handling a modem crash or shutdown. Take and later release an IPA clock reference in ipa_modem_crashed(), to ensure the hardware is operational. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-28net: ipa: get another clock for ipa_setup()Alex Elder
Two places call ipa_setup(). The first, ipa_probe(), holds an IPA clock reference when calling ipa_setup() (if the AP is responsible for IPA firmware loading). But if the modem is loading IPA firmware, ipa_smp2p_modem_setup_ready_isr() calls ipa_setup() after the modem has signaled the hardware is ready. This can happen at any time, and there is no guarantee the hardware is active. Have ipa_smp2p_modem_setup() take an IPA clock reference before it calls ipa_setup(), and release it once setup is complete. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-28net: ipa: get clock in ipa_probe()Alex Elder
Any entry point that leads to IPA hardware access must ensure the hardware is operational (clocked). Currently we ensure this by taking an extra clock reference during setup that is not released until we receive a system suspend request. But this extra reference will soon go away. When the platform driver ->probe function is called, we first need hardware access in ipa_config(). Although ipa_config() takes an IPA clock reference, it the special reference taken to prevent suspending the hardware. Have ipa_probe() take a reference before calling ipa_config(), so that the "no-suspend" reference can eventually go away. Drop this reference before ipa_probe() returns. Similarly, the driver ->remove function can be called at any time. Take an IPA clock reference at the beginning of that function, and drop it again after the deconfig stage has completed (at which point hardware access is no longer needed). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>