firmware: qcom: scm: request the waitqueue irq *after* initializing SCM

There's a subtle race in the SCM driver: we assign the __scm pointer
before requesting the waitqueue interrupt. Assigning __sc

firmware: qcom: scm: request the waitqueue irq *after* initializing SCM

There's a subtle race in the SCM driver: we assign the __scm pointer
before requesting the waitqueue interrupt. Assigning __scm marks the SCM
API as ready to accept calls. It's possible that a user makes a call
right after we set __scm and the firmware raises an interrupt before the
driver's ready to service it. Move the __scm assignment after we request
the interrupt.

This has the added benefit of allowing us to drop the goto label.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20250630-qcom-scm-race-v2-4-fa3851c98611@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

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firmware: qcom: scm: initialize tzmem before marking SCM as available

Now that qcom_scm_shm_bridge_enable() uses the struct device passed to
it as argument to make the QCOM_SCM_MP_SHM_BRIDGE_ENABLE

firmware: qcom: scm: initialize tzmem before marking SCM as available

Now that qcom_scm_shm_bridge_enable() uses the struct device passed to
it as argument to make the QCOM_SCM_MP_SHM_BRIDGE_ENABLE SCM call, we
can move the TZMem initialization before the assignment of the __scm
pointer in the SCM driver (which marks SCM as ready to users) thus
fixing the potential race between consumer calls and the memory pool
initialization.

Reported-by: Johan Hovold <johan+linaro@kernel.org>
Closes: https://lore.kernel.org/all/20250120151000.13870-1-johan+linaro@kernel.org/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20250630-qcom-scm-race-v2-3-fa3851c98611@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

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firmware: qcom: scm: take struct device as argument in SHM bridge enable

qcom_scm_shm_bridge_enable() is used early in the SCM initialization
routine. It makes an SCM call and so expects the interna

firmware: qcom: scm: take struct device as argument in SHM bridge enable

qcom_scm_shm_bridge_enable() is used early in the SCM initialization
routine. It makes an SCM call and so expects the internal __scm pointer
in the SCM driver to be assigned. For this reason the tzmem memory pool
is allocated *after* this pointer is assigned. However, this can lead to
a crash if another consumer of the SCM API makes a call using the memory
pool between the assignment of the __scm pointer and the initialization
of the tzmem memory pool.

As qcom_scm_shm_bridge_enable() is a special case, not meant to be
called by ordinary users, pull it into the local SCM header. Make it
take struct device as argument. This is the device that will be used to
make the SCM call as opposed to the global __scm pointer. This will
allow us to move the tzmem initialization *before* the __scm assignment
in the core SCM driver.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250630-qcom-scm-race-v2-2-fa3851c98611@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

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firmware: qcom: scm: remove unused arguments from SHM bridge routines

qcom_scm_shm_bridge_create() and qcom_scm_shm_bridge_delete() take
struct device as argument but don't use it. Remove it from th

firmware: qcom: scm: remove unused arguments from SHM bridge routines

qcom_scm_shm_bridge_create() and qcom_scm_shm_bridge_delete() take
struct device as argument but don't use it. Remove it from these
functions' prototypes.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20250630-qcom-scm-race-v2-1-fa3851c98611@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

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