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path: root/drivers/net/ipa/gsi.c
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2020-11-28net: ipa: adjust GSI register addressesAlex Elder
The offsets for almost all GSI registers we use have different offsets starting at IPA version 4.5. Only two registers remain in their original location. In a way though, the new register locations are not *that* different. The entire group of affected registers has simply been shifted down in memory by a fixed amount (0xd000). So for example, the channel context 0 register that has a base offset of 0x0001c000 for "older" hardware now has a base offset of 0x0000f000. This patch aims to add support for IPA v4.5 registers at their new offets in a way that minimizes the amount of code that needs to change. It is not ideal, but it avoids the need to maintain a nearly complete set of additional register offset definitions. The approach takes advantage of the fact that when accessing GSI registers we do not access any of memory at lower end of the "gsi" memory range (with two exceptions already noted). In particular, we do not access anything within the bottom 0xd000 bytes of the GSI memory range. For IPA version 4.5, after we map the GSI memory, we adjust the virtual memory pointer downward by the fixed amount (0xd000). That way, register accesses using the offsets defined by the existing GSI_REG_*() macros will resolve to the proper locations for IPA version 4.5. The two registers *not* affected by this offset are accessed only in gsi_irq_setup(). There, for IPA version 4.5, we undo the general register adjustment by adding the fixed amount back to the virtual address to access these registers. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-28net: ipa: update gsi registers for IPA v4.5Alex Elder
Very few GSI register definitions change for IPA v4.5, however as a group their position in memory shifts a constant amount (handled by the next commit). Add definitions and update comments to the set of GSI registers to support changes that come with IPA v4.5. Update the logic in gsi_channel_program() to accommodate the new (expanded) PREFETCH_MODE field in the CH_C_QOS register. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-28net: ipa: reverse logic on escape buffer useAlex Elder
Starting with IPA v4.2 there is a GSI channel option to use an "escape buffer" instead of prefetch buffers. This should be used for all channels *except* the AP command TX channel. The logic that implements this has it backwards; fix this bug. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-20net: ipa: support retries on generic GSI commandsAlex Elder
When stopping an AP RX channel, there can be a transient period while the channel enters STOP_IN_PROC state before reaching the final STOPPED state. In that case we make another attempt to stop the channel. Similarly, when stopping a modem channel (using a GSI generic command issued from the AP), it's possible that multiple attempts will be required before the channel reaches STOPPED state. Add a field to the GSI structure to record an errno representing the result code provided when a generic command completes. If the result learned in gsi_isr_gp_int1() is RETRY, record -EAGAIN in the result code, otherwise record 0 for success, or -EIO for any other result. If we time out nf gsi_generic_command() waiting for the command to complete, return -ETIMEDOUT (as before). Otherwise return the result stashed by gsi_isr_gp_int1(). Add a loop in gsi_modem_channel_halt() to reissue the HALT command if the result code indicates -EAGAIN. Limit this to 10 retries (after the initial attempt). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-20net: ipa: ignore CHANNEL_NOT_RUNNING errorsAlex Elder
IPA v4.2 has a hardware quirk that requires the AP to allocate GSI channels for the modem to use. It is recommended that these modem channels get stopped (with a HALT generic command) by the AP when its IPA driver gets removed. The AP has no way of knowing the current state of a modem channel. So when the IPA driver issues a HALT command it's possible the channel is not running, and in that case we get an error indication. This error simply means we didn't need to stop the channel, so we can ignore it. This patch adds an explanation for this situation, and arranges for this condition to *not* report an error message. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-20net: ipa: don't reset an ALLOCATED channelAlex Elder
If the rmnet_ipa0 network device has not been opened at the time we remove or shut down the IPA driver, its underlying TX and RX GSI channels will not have been started, and they will still be in ALLOCATED state. The RESET command on a channel is meant to return a channel to ALLOCATED state after it's been stopped. But if it was never started, its state will still be ALLOCATED, the RESET command is not required. Quietly skip doing the reset without printing an error message if a channel is already in ALLOCATED state when we request it be reset. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-20net: ipa: print channel/event ring number on errorAlex Elder
When a GSI command is used to change the state of a channel or event ring we check the state before and after the command to ensure it is as expected. If not, we print an error message, but it does not include the channel or event ring id, and it easily can. Add the channel or event ring id to these error messages. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-13net: ipa: use enumerated types for GSI field valuesAlex Elder
Replace constants defined with an "_FVAL" suffix with values defined in enumerated types, to be consistent with other usage in the driver. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-13net: ipa: move GSI command opcode values into "gsi_reg.h"Alex Elder
The gsi_ch_cmd_opcode, gsi_evt_cmd_opcode, and gsi_generic_cmd_opcode enumerated types are values that fields in the GSI command registers can take on. Move their definitions out of "gsi.c" and into "gsi_reg.h", alongside the definition of registers they are associated with. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-13net: ipa: move GSI error values into "gsi_reg.h"Alex Elder
The gsi_err_code and gsi_err_type enumerated types are values that fields in the GSI ERROR_LOG register can take on. Move their definitions out of "gsi.c" and into "gsi_reg.h", alongside the definition of the ERROR_LOG register offset and field symbols. Drop the "_ERR" suffix in the names of the gsi_err_code members. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-13net: ipa: move channel type values into "gsi_reg.h"Alex Elder
The gsi_channel_type enumerated type define values used for the channel type/protocol for event rings and channels. Move its definition out of "gsi.c" and into "gsi_reg.h", alongside the definition of the CH_C_CNTXT_0 register offset and its fields. Add a comment near the definition of the EV_CH_E_CNTXT_0 register indicating this type is used for its EV_CHTYPE field. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-13net: ipa: use common value for channel type and protocolAlex Elder
The numeric values that represent the event ring channel type are identical to the values that represent the matching protocol used for a channel. Use a new gsi_channel_type enumerated type to represent the values programmed for both cases, using "CHANNEL_TYPE" in member names in place of "EVT_CHTYPE" and "CHANNEL_PROTOCOL". Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-13net: ipa: define GSI interrupt types with enumsAlex Elder
Define the GSI global interrupt types with an enumerated type whose values are the bit positions representing the global interrupt types. Similarly, define the GSI general interrupt types with an enumerated type whose values are the bit positions of general interrupt types. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-11net: ipa: drop an error messageAlex Elder
There is no need for gsi_modem_channel_halt() to report an error, because gsi_generic_command() will already have done that if the command times out. So get rid of the extra message. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: pass a value to gsi_irq_type_update()Alex Elder
Now that all of the GSI interrupts are handled uniformly, change gsi_irq_type_update() so it takes a value. Have the function assign that value to the cached mask of enabled GSI IRQ types before writing it to hardware. Note that gsi_irq_teardown() will only be called after gsi_irq_disable(), so it's not necessary for the former to disable all IRQ types. Get rid of that. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: only enable GSI general IRQs when neededAlex Elder
Most GSI general errors are unrecoverable without a full reset. Despite that, we want to receive these errors so we can at least report what happened before whatever undefined behavior ensues. Explicitly disable all such interrupts in gsi_irq_setup(), then enable those we want in gsi_irq_enable(). List the interrupt types we are interested in (everything but breakpoint) explicitly rather than using GSI_CNTXT_GSI_IRQ_ALL, and remove that symbol's definition. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: explicitly disallow inter-EE interruptsAlex Elder
It is possible for other execution environments (EEs, like the modem) to request changes to local (AP) channel or event ring state. We do not support this feature. In gsi_irq_setup(), explicitly zero the mask that defines which channels are permitted to generate inter-EE channel state change interrupts. Do the same for the event ring mask. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: only enable GSI IEOB IRQs when neededAlex Elder
A GSI channel must be started in order to use it to perform a transfer data (or command) transaction. And the only time we'll see an IEOB interrupt is if we send a transaction to a started channel. Therefore we do not need to have the IEOB interrupt type enabled until at least one channel has been started. And once the last started channel has been stopped, we can disable the IEOB interrupt type again. We already enable the IEOB interrupt for a particular channel only when it is started. Extend that by having the IEOB interrupt *type* be enabled only when at least one channel is in STARTED state. Disallow all channels from triggering the IEOB interrupt in gsi_irq_setup(). We only enable an channel's interrupt when needed, so there is no longer any need to zero the channel mask in gsi_irq_disable(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: only enable generic command completion IRQ when neededAlex Elder
The completion of a generic EE GSI command is signaled by a global interrupt of type GP_INT1. The only other used type for a global interrupt is a hardware error report. First, disallow all global interrupt types in gsi_irq_setup(). We want to know about hardware errors, so re-enable the interrupt type in gsi_irq_enable(), to allow hardware errors to be reported. Disable that interrupt type again in gsi_irq_disable(). We only issue generic EE commands one at a time, and there's no reason to keep the completion interrupt enabled when no generic EE command is pending. We furthermore have no need to enable the GP_INT2 or GP_INT3 interrupt types (which aren't used). The change in gsi_irq_enable() makes GSI_CNTXT_GLOB_IRQ_ALL unused, so get rid of it. Have gsi_generic_command() enable the GP_INT1 interrupt type (in addition to the ERROR_INT type) only while a generic command is pending. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: only enable GSI event control IRQs when neededAlex Elder
A GSI event ring causes an event control interrupt to fire whenever its state changes (between NOT_ALLOCATED and ALLOCATED). No event ring should ever change state except when we request it to. Currently, we permit *all* events rings to generate event control interrupts--even those that are never used. And we enable event control interrupts essentially at all times, from setup to teardown. Instead, only enable the event control interrupt type for the duration of an event ring command, and when doing so, only allow the event ring being operated upon to cause the interrupt to fire. Disallow all event rings from issuing the event control interrupt in gsi_irq_setup(). Because an event ring's interrupt is only enabled when needed, there is no longer any need to zero the event channel mask in gsi_irq_disable(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: only enable GSI channel control IRQs when neededAlex Elder
A GSI channel causes a channel control interrupt to fire whenever its state changes (between NOT_ALLOCATED, ALLOCATED, STARTED, etc.). We do not support inter-EE channel commands (initiated by other EEs), so no channel should ever change state except when we request it to. Currently, we permit *all* channels to generate channel control interrupts--even those that are never used. And we enable channel control interrupts essentially at all times, from setup to teardown. Instead, disable all channel control interrupts initially in gsi_irq_setup(), and only enable the channel control interrupt type for the duration of a channel command. When doing so, only allow the channel being operated upon to cause the interrupt to fire. Because a channel's interrupt is now enabled only when needed (one channel at a time), there is no longer any need to zero the channel mask in gsi_irq_disable(). Add new gsi_irq_type_enable() and gsi_irq_type_disable() as helper functions to control whether a given GSI interrupt type is enabled. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: cache last-saved GSI IRQ enabled typeAlex Elder
Keep track of the set of GSI interrupt types that are currently enabled by recording the mask value to write (or last written) to the TYPE_IRQ_MSK register. Create a new helper function gsi_irq_type_update() to handle actually writing the register. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: disable all GSI interrupt types initiallyAlex Elder
Introduce gsi_irq_setup() and gsi_irq_teardown() to disable all GSI interrupts when first setting up GSI hardware, and to clean things up when we're done. Re-enable all GSI interrupt types in gsi_irq_enable(), but do so only after each of the type-specific interrupt masks has been configured. Similarly, disable all interrupt types in gsi_irq_disable()--first--before zeroing out the type-specific masks. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: define GSI interrupt types with an enumAlex Elder
Define the GSI interrupt types with an enumerated type whose values are the bit positions representing each interrupt type. Include a short comment describing how each interrupt type is used. Build up the enabled interrupt mask explicitly in gsi_irq_enable(), and get rid of the definition of GSI_CNTXT_TYPE_IRQ_MSK_ALL. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: rename gsi->event_enable_bitmapAlex Elder
Rename the "event_enable_bitmap" field of the GSI structure to be "ieob_enabled_bitmap". An upcoming patch will cache the last value stored for another interrupt mask and this is a more direct naming convention to follow. Add a few comments to explain the bitmap fields in the GSI structure. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-07net: ipa: request GSI IRQ laterAlex Elder
Introduce gsi_irq_init() and gsi_irq_exit(), to encapsulate looking up the GSI IRQ and registering its handler. Call gsi_irq_init() a little later in gsi_init(), and initialize the completion earlier. The IRQ handler accesses both the GSI virtual memory pointer and the completion, and this way these things will have been initialized before the gsi_irq() can ever be called. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-04net: ipa: eliminate legacy argumentsAlex Elder
We enable a channel doorbell engine only for IPA v3.5.1, and that is now handled directly by gsi_channel_program(). When initially setting up a channel, we want that doorbell engine enabled, and we can request that independent of the IPA version. Doing that makes the "legacy" argument to gsi_channel_setup_one() unnecessary. And with that gone we can get rid of the "legacy" argument to gsi_channel_setup(), and gsi_setup() as well. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-04net: ipa: use version in gsi_channel_program()Alex Elder
Use the IPA version in gsi_channel_program() to determine whether we should enable the GSI doorbell engine when requested. This way, callers only say whether or not it should be enabled if needed, regardless of hardware version. Rename the "legacy" argument to gsi_channel_reset(), and have it indicate whether the doorbell engine should be enabled when reprogramming following the reset. Change all callers of gsi_channel_reset() to indicate whether to enable the doorbell engine after reset, independent of hardware version. Rework a little logic in ipa_endpoint_reset() to get rid of the "legacy" variable previously passed to gsi_channel_reset(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-04net: ipa: use version in gsi_channel_reset()Alex Elder
A quirk of IPA v3.5.1 requires a channel reset on an RX channel to be performed twice. Use the IPA version in gsi_channel_reset() rather than the passed-in legacy flag to determine that. This is actually a bug fix, because this double reset is supposed to occur independent of whether we're enabling the doorbell engine. Now they will be independent. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-04net: ipa: use version in gsi_channel_init()Alex Elder
A quirk of IPA v4.2 requires the AP to allocate the GSI channels that are owned by the modem. Rather than pass a flag argument to gsi_channel_init(), use the IPA version directly in that function to determine whether modem channels need to be allocated. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-04net: ipa: record IPA version in GSI structureAlex Elder
Record the IPA version passed to gsi_init() in the GSI structure. This allows that value to be used directly where needed, rather than passing and storing certain flag arguments through the code. In particular, for all but one supported version of IPA, the command channel is programmed to only use an "escape buffer". By storing the IPA version, we can do a simple version check in one location, and avoid storing a flag field in every channel (and passing a flag along while initializing channels to set that field properly). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-04net: ipa: expose IPA version to the GSI layerAlex Elder
Although GSI is integral to IPA, it is a separate hardware component and the IPA code supporting it has been structured to avoid explicit dependence on IPA details. An example of this is that gsi_init() is passed a number of Boolean flags to indicate special behaviors, whose values are dependent on the IPA hardware version. Looking ahead, newer hardware versions would require even more such special behaviors. For any given version of IPA hardware (like 3.5.1 or 4.2), the GSI hardware version is fixed (in this case, 1.3 and 2.2, respectively). So the IPA version *implies* the GSI version, and the IPA version can be used as effectively the equivalent of the GSI hardware version. Rather than proliferating new special behavior flags, just provide the IPA version to the GSI layer when it is initialized. The GSI code can then use that directly to determine whether special behaviors are required. The IPA version enumerated type is already isolated to its own header file, so the exposure of this IPA detail is very limited. For now, just change gsi_init() to pass the version rather than the Boolean flags, and set the flag values internal to that function. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-28net: ipa: fix two mild warningsAlex Elder
Fix two spots where a variable "channel_id" is unnecessarily redefined inside loops in "gsi.c". This is warned about if "W=2" is added to the build command. Note that this problem is harmless, so there's no need to backport it as a bugfix. Remove a comment in gsi_init() about waking the system; the GSI interrupt does not wake the system any more. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28net: ipa: share field mask values for GSI general interruptAlex Elder
The GSI general interrupt is managed by three registers: enable; status; and clear. The three registers have same set of field bits at the same locations. Use a common set of field masks for all three registers to avoid duplication. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28net: ipa: share field mask values for GSI global interruptAlex Elder
The GSI global interrupt is managed by three registers: enable; status; and clear. The three registers have same set of field bits at the same locations. Use a common set of field masks for all three registers to avoid duplication. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28net: ipa: share field mask values for GSI interrupt typeAlex Elder
The GSI interrupt type register and interrupt type mask register have the same field bits at the same locations. Use a common set of field masks for both registers rather than essentially duplicating them. The only place the interrupt mask register uses any of these is in gsi_irq_enable(). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18net: ipa: do not enable GSI interrupt for wakeupAlex Elder
We now trigger a system resume when we receive an IPA SUSPEND interrupt. We should *not* wake up on GSI interrupts. Signed-off-by: Alex Elder <elder@linaro.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-13net: ipa: fix kerneldoc commentsAlex Elder
This commit affects comments (and in one case, whitespace) only. Throughout the IPA code, return statements are documented using "@Return:", whereas they should use "Return:" instead. Fix these mistakes. In function definitions, some parameters are missing their comment to describe them. And in structure definitions, some fields are missing their comment to describe them. Add these missing descriptions. Some arguments changed name and type along the way, but their descriptions were not updated (an endpoint pointer is now used in many places that previously used an endpoint ID). Fix these incorrect parameter descriptions. In the description for the ipa_clock structure, one field had a semicolon instead of a colon in its description. Fix this. Add a missing function description for ipa_gsi_endpoint_data_empty(). All of these issues were identified when building with "W=1". Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
All conflicts seemed rather trivial, with some guidance from Saeed Mameed on the tc_ct.c one. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-01net: ipa: standarize more GSI error messagesAlex Elder
Make minor updates to error messages reported in "gsi.c": - Use local variables to reduce multi-line function calls - Don't use parentheses in messages - Do some slight rewording in a few cases Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-01net: ipa: always report GSI state errorsAlex Elder
We check the state of an event ring or channel both before and after any GSI command issued that will change that state. In most--but not all--cases, if the state is something different than expected we report an error message. Add error messages where missing, so that all unexpected states provide information about what went wrong. Drop the parentheses around the state value shown in all cases. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-30net: ipa: always check for stopped channelAlex Elder
In gsi_channel_stop(), there's a check to see if the channel might have entered STOPPED state since a previous call, which might have timed out before stopping completed. That check actually belongs in gsi_channel_stop_command(), which is called repeatedly by gsi_channel_stop() for RX channels. Fixes: 650d1603825d ("soc: qcom: ipa: the generic software interface") Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-27drivers: ipa: fix typoes for ipaWang Wenhu
Change "transactio" -> "transaction". Also an alignment correction. Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
The MSCC bug fix in 'net' had to be slightly adjusted because the register accesses are done slightly differently in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-16net: ipa: do not clear interrupt in gsi_channel_start()Alex Elder
In gsi_channel_start() there is harmless-looking comment "Clear the channel's event ring interrupt in case it's pending". The intent was to avoid getting spurious interrupts when first bringing up a channel. However we now use channel stop/start to implement suspend and resume, and an interrupt pending at the time we resume is actually something we don't want to ignore. The very first time we bring up the channel we do not expect an interrupt to be pending, and even if it were, the effect would simply be to schedule NAPI on that channel, which would find nothing to do, which is not a problem. Stop clearing any pending IEOB interrupt in gsi_channel_start(). That leaves one caller of the trivial function gsi_isr_ieob_clear(). Get rid of that function and just open-code it in gsi_isr_ieob() instead. This fixes a problem where suspend/resume IPA v4.2 would get stuck when resuming after a suspend. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-16net: ipa: don't be a hog in gsi_channel_poll()Alex Elder
The iteration count value used in gsi_channel_poll() is intended to limit poll iterations to the budget supplied as an argument. But it's never updated. Fix this bug by incrementing the count each time through the loop. Reported-by: Sharath Chandra Vurukala <sharathv@codeaurora.com> Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Conflicts were all overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06net: ipa: only reset channel twice for IPA v3.5.1Alex Elder
In gsi_channel_reset(), RX channels are subjected to two consecutive CHANNEL_RESET commands. This workaround should only be used for IPA version 3.5.1, and for newer hardware "can lead to unwanted behavior." Only issue the second CHANNEL_RESET command for legacy hardware. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06net: ipa: rename db_enable flagAlex Elder
In several places, a Boolean flag is used in the GSI code to indicate whether the "doorbell engine" should be enabled or not when a channel is configured. This is basically done to abstract this property from the IPA version; the GSI code doesn't otherwise "know" what the IPA hardware version is. The doorbell engine is enabled only for IPA v3.5.1, not for IPA v4.0 and later. The next patch makes another change that affects behavior during channel reset (which also involves programming the channel). It also distinguishes IPA v3.5.1 hardware from newer hardware. Rather than creating another flag whose value matches the "db_enable" value, just rename "db_enable" to be "legacy" so it can be used to signal more than just the special doorbell handling. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-01net: ipa: do not cache channel stateAlex Elder
It is possible for a GSI channel's state to be changed as a result of an action by a different execution environment. Specifically, the modem is able to issue a GSI generic command that causes a state change on a GSI channel associated with the AP. A channel's state only needs to be known when a channel is allocated or deallocaed, started or stopped, or reset. So there is little value in caching the state anyway. Stop recording a copy of the channel's last known state, and instead fetch the true state from hardware whenever it's needed. In such cases, *do* record the state in a local variable, in case an error message reports it (so the value reported is the value seen). Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>