From: Chris Lew <quic_clew@xxxxxxxxxxx> [ Upstream commit 2e3f0d693875db698891ffe89a18121bda5b95b8 ] Add qcom_smem_bust_hwspin_lock_by_host to enable remoteproc to bust the hwspin_lock owned by smem. In the event the remoteproc crashes unexpectedly, the remoteproc driver can invoke this API to try and bust the hwspin_lock and release the lock if still held by the remoteproc device. Signed-off-by: Chris Lew <quic_clew@xxxxxxxxxxx> Reviewed-by: Bjorn Andersson <quic_bjorande@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20240529-hwspinlock-bust-v3-3-c8b924ffa5a2@xxxxxxxxxxx Signed-off-by: Bjorn Andersson <andersson@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/soc/qcom/smem.c | 26 ++++++++++++++++++++++++++ include/linux/soc/qcom/smem.h | 2 ++ 2 files changed, 28 insertions(+) diff --git a/drivers/soc/qcom/smem.c b/drivers/soc/qcom/smem.c index d4a89d2bb43bb..2e8568d6cde94 100644 --- a/drivers/soc/qcom/smem.c +++ b/drivers/soc/qcom/smem.c @@ -359,6 +359,32 @@ static struct qcom_smem *__smem; /* Timeout (ms) for the trylock of remote spinlocks */ #define HWSPINLOCK_TIMEOUT 1000 +/* The qcom hwspinlock id is always plus one from the smem host id */ +#define SMEM_HOST_ID_TO_HWSPINLOCK_ID(__x) ((__x) + 1) + +/** + * qcom_smem_bust_hwspin_lock_by_host() - bust the smem hwspinlock for a host + * @host: remote processor id + * + * Busts the hwspin_lock for the given smem host id. This helper is intended + * for remoteproc drivers that manage remoteprocs with an equivalent smem + * driver instance in the remote firmware. Drivers can force a release of the + * smem hwspin_lock if the rproc unexpectedly goes into a bad state. + * + * Context: Process context. + * + * Returns: 0 on success, otherwise negative errno. + */ +int qcom_smem_bust_hwspin_lock_by_host(unsigned int host) +{ + /* This function is for remote procs, so ignore SMEM_HOST_APPS */ + if (host == SMEM_HOST_APPS || host >= SMEM_HOST_COUNT) + return -EINVAL; + + return hwspin_lock_bust(__smem->hwlock, SMEM_HOST_ID_TO_HWSPINLOCK_ID(host)); +} +EXPORT_SYMBOL_GPL(qcom_smem_bust_hwspin_lock_by_host); + /** * qcom_smem_is_available() - Check if SMEM is available * diff --git a/include/linux/soc/qcom/smem.h b/include/linux/soc/qcom/smem.h index a36a3b9d4929e..03187bc958518 100644 --- a/include/linux/soc/qcom/smem.h +++ b/include/linux/soc/qcom/smem.h @@ -14,4 +14,6 @@ phys_addr_t qcom_smem_virt_to_phys(void *p); int qcom_smem_get_soc_id(u32 *id); +int qcom_smem_bust_hwspin_lock_by_host(unsigned int host); + #endif -- 2.43.0
