firmware: qcom: scm: Fix interrupted SCM calls
authorAndy Gross <andy.gross@linaro.org>
Tue, 4 Apr 2017 19:32:32 +0000 (19:32 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 12 Apr 2017 10:41:21 +0000 (12:41 +0200)
commitbec9918bb4dae2099c37791133403c32aa2738c7
tree8bda4c001768c2246736edbd2b833b1d236d6613
parent007f0a2f2c0fcfa9ecef016c0910aebd0b784fdd
firmware: qcom: scm: Fix interrupted SCM calls

[ Upstream commit 82bcd087029f6056506ea929f11af02622230901 ]

This patch adds a Qualcomm specific quirk to the arm_smccc_smc call.

On Qualcomm ARM64 platforms, the SMC call can return before it has
completed.  If this occurs, the call can be restarted, but it requires
using the returned session ID value from the interrupted SMC call.

The quirk stores off the session ID from the interrupted call in the
quirk structure so that it can be used by the caller.

This patch folds in a fix given by Sricharan R:
https://lkml.org/lkml/2016/9/28/272

Signed-off-by: Andy Gross <andy.gross@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/arm64/kernel/smccc-call.S
drivers/firmware/qcom_scm-64.c
include/linux/arm-smccc.h