From: Arnd Bergmann <arnd@arndb.de>
If the iwlmei code is a loadable module, the main iwlwifi driver
cannot be built-in:
x86_64-linux-ld: drivers/net/wireless/intel/iwlwifi/pcie/trans.o: in function `iwl_pcie_prepare_card_hw':
trans.c:(.text+0x4158): undefined reference to `iwl_mei_is_connected'
Unfortunately, Kconfig enforces the opposite, forcing the MEI driver to
not be built-in if iwlwifi is a module.
There is no easy way to express the correct dependency in Kconfig,
this is the best workaround I could come up with, turning CONFIG_IWLMEI
into a 'bool' symbol, and spelling out the exact conditions under which
it may be enabled, and then using Makefile logic to ensure it is
built-in when iwlwifi is.
A better option would be change iwl_mei_is_connected() so it could be
called from iwlwifi regardless of whether the mei driver is reachable,
but that requires a larger rework in the driver.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/net/wireless/intel/iwlwifi/Kconfig | 6 +++---
drivers/net/wireless/intel/iwlwifi/Makefile | 3 +--
drivers/net/wireless/intel/iwlwifi/mei/Makefile | 4 +++-
3 files changed, 7 insertions(+), 6 deletions(-)
Subject: [PATCH] iwlwifi: work around reverse dependency on MEI
From: Arnd Bergmann <arnd@arndb.de>
If the iwlmei code is a loadable module, the main iwlwifi driver cannot be
built-in:
x86_64-linux-ld: drivers/net/wireless/intel/iwlwifi/pcie/trans.o: in function
`iwl_pcie_prepare_card_hw':
trans.c:(.text+0x4158): undefined reference to `iwl_mei_is_connected'
Unfortunately, Kconfig enforces the opposite, forcing the MEI driver to not
be built-in if iwlwifi is a module.
There is no easy way to express the correct dependency in Kconfig, this is the
best workaround I could come up with, turning CONFIG_IWLMEI into a 'bool'
symbol, and spelling out the exact conditions under which it may be enabled,
and then using Makefile logic to ensure it is built-in when iwlwifi is.
A better option would be change iwl_mei_is_connected() so it could be
called from iwlwifi regardless of whether the mei driver is reachable, but that
requires a larger rework in the driver.
I can try to do that but I don't really see how..
I can't really make a function that would behave differently based on whether the symbol is available or not.
@@ -93,10 +93,10 @@ config IWLWIFI_BCAST_FILTERINGexpectincomingbroadcastsfortheirnormaloperations.configIWLMEI-tristate"Intel Management Engine communication over WLAN"-depends onINTEL_MEI+bool"Intel Management Engine communication over WLAN"+depends onINTEL_MEI=y||INTEL_MEI=IWLMVM+depends onIWLMVM=y||IWLWIFI=mdepends onPM-depends onIWLMVMhelpEnablestheiwlmeikernelmodule.
Johannes suggested to make IWLMVM depend on IWLMEI || !IWLMEI
That worked as well, I just had issues with this in our internal backport based tree.
I need to spend a bit more time on this, but I admit my total ignorance in Kconfig's dialect.
On Tue, Dec 7, 2021 at 2:19 PM Grumbach, Emmanuel
[off-list ref] wrote:
quoted
A better option would be change iwl_mei_is_connected() so it could be
called from iwlwifi regardless of whether the mei driver is reachable, but that
requires a larger rework in the driver.
I can try to do that but I don't really see how..
I can't really make a function that would behave differently based on whether the symbol is available or not.
I meant that this would be an inline function that only accesses variables
that are available to the iwlwifi driver already, rather than part of the iwlmei
driver.
Part of the problem here is that the current implementation checks a global
variable that is part of the iwlmei driver, so there is no easy way for iwlwifi
to access it.
quoted
config IWLMEI- tristate "Intel Management Engine communication over WLAN"- depends on INTEL_MEI+ bool "Intel Management Engine communication over WLAN"+ depends on INTEL_MEI=y || INTEL_MEI=IWLMVM+ depends on IWLMVM=y || IWLWIFI=m depends on PM- depends on IWLMVM help Enables the iwlmei kernel module.
Johannes suggested to make IWLMVM depend on IWLMEI || !IWLMEI
That worked as well, I just had issues with this in our internal backport based tree.
I need to spend a bit more time on this, but I admit my total ignorance in Kconfig's dialect.
It's still not enough, the dependency is in iwlwifi, not in iwlmvm, so it
would remain broken for IWLWIFI=y IWLMVM=m IWLMEI=m.
One easy solution might be to link all the iwlmei objects intro the main
iwlwifi driver, the same way it links in the fw/*.c files.
Arnd
@@ -93,10 +93,10 @@ config IWLWIFI_BCAST_FILTERINGexpectincomingbroadcastsfortheirnormaloperations.configIWLMEI-tristate"Intel Management Engine communication over WLAN"-depends onINTEL_MEI+bool"Intel Management Engine communication over WLAN"+depends onINTEL_MEI=y||INTEL_MEI=IWLMVM+depends onIWLMVM=y||IWLWIFI=m
For reference, that line is wrong, and I still see the same problem
with my patch
applied. It should work after changing it to
depends on IWLMVM=y || IWLMVM=m
but I'm still testing for further problems.
Arnd
From: Johannes Berg <johannes@sipsolutions.net> Date: 2021-12-07 14:40:39
On Tue, 2021-12-07 at 14:25 +0100, Arnd Bergmann wrote:
quoted
quoted
config IWLMEI- tristate "Intel Management Engine communication over WLAN"- depends on INTEL_MEI+ bool "Intel Management Engine communication over WLAN"+ depends on INTEL_MEI=y || INTEL_MEI=IWLMVM+ depends on IWLMVM=y || IWLWIFI=m depends on PM- depends on IWLMVM help Enables the iwlmei kernel module.
Johannes suggested to make IWLMVM depend on IWLMEI || !IWLMEI
That worked as well, I just had issues with this in our internal backport based tree.
I need to spend a bit more time on this, but I admit my total ignorance in Kconfig's dialect.
It's still not enough, the dependency is in iwlwifi, not in iwlmvm, so it
would remain broken for IWLWIFI=y IWLMVM=m IWLMEI=m.
I missed the pcie/trans.c dependency, and the others are (I think) in
mvm...
but then we can do
config IWLWIFI
...
depends on IWLMEI || !IWLMEI
...
no? That way, we exclude IWLWIFI=y && IWLMEI=m, which I believe causes
the issue? And IWLMVM already depends on IWLWIFI (via the if clause), so
that
johannes
On Tue, Dec 7, 2021 at 3:40 PM Johannes Berg [off-list ref] wrote:
On Tue, 2021-12-07 at 14:25 +0100, Arnd Bergmann wrote:
quoted
quoted
quoted
config IWLMEI- tristate "Intel Management Engine communication over WLAN"- depends on INTEL_MEI+ bool "Intel Management Engine communication over WLAN"+ depends on INTEL_MEI=y || INTEL_MEI=IWLMVM+ depends on IWLMVM=y || IWLWIFI=m depends on PM- depends on IWLMVM help Enables the iwlmei kernel module.
Johannes suggested to make IWLMVM depend on IWLMEI || !IWLMEI
That worked as well, I just had issues with this in our internal backport based tree.
I need to spend a bit more time on this, but I admit my total ignorance in Kconfig's dialect.
It's still not enough, the dependency is in iwlwifi, not in iwlmvm, so it
would remain broken for IWLWIFI=y IWLMVM=m IWLMEI=m.
I missed the pcie/trans.c dependency, and the others are (I think) in
mvm...
but then we can do
config IWLWIFI
...
depends on IWLMEI || !IWLMEI
...
no? That way, we exclude IWLWIFI=y && IWLMEI=m, which I believe causes
the issue? And IWLMVM already depends on IWLWIFI (via the if clause), so
that
Right, that should work. Testing with that version now.
Arnd