remoteproc: qcom_q6v5_pas: Add hwspinlock bust on stop

When remoteproc goes down unexpectedly this results in a state where any
acquired hwspinlocks will remain locked possibly resulting in deadlock.
In order to ensure all locks are freed we include a call to
qcom_smem_bust_hwspin_lock_by_host() during remoteproc shutdown.

For qcom_q6v5_pas remoteprocs, each remoteproc has an assigned smem
host_id. Remoteproc can pass this id to smem to try and bust the lock on
remoteproc stop.

This edge case only occurs with q6v5_pas watchdog crashes. The error
fatal case has handling to clear the hwspinlock before the error fatal
interrupt is triggered.

Signed-off-by: Richard Maina <[e-mail]>
Reviewed-by: Bjorn Andersson <[e-mail]>
Signed-off-by: Chris Lew <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bjorn Andersson <[e-mail]>

drivers/remoteproc/qcom_q6v5_pas.c

···
 	const char *ssr_name;
 	const char *sysmon_name;
 	int ssctl_id;
+	unsigned int smem_host_id;
 
 	int region_assign_idx;
 	int region_assign_count;
···
 	int lite_pas_id;
 	unsigned int minidump_id;
 	int crash_reason_smem;
+	unsigned int smem_host_id;
 	bool decrypt_shutdown;
 	const char *info_name;
 
···
 	handover = qcom_q6v5_unprepare(&adsp->q6v5);
 	if (handover)
 		qcom_pas_handover(&adsp->q6v5);
+
+	if (adsp->smem_host_id)
+		ret = qcom_smem_bust_hwspin_lock_by_host(adsp->smem_host_id);
 
 	return ret;
 }
···
 	adsp->pas_id = desc->pas_id;
 	adsp->lite_pas_id = desc->lite_pas_id;
 	adsp->info_name = desc->sysmon_name;
+	adsp->smem_host_id = desc->smem_host_id;
 	adsp->decrypt_shutdown = desc->decrypt_shutdown;
 	adsp->region_assign_idx = desc->region_assign_idx;
 	adsp->region_assign_count = min_t(int, MAX_ASSIGN_COUNT, desc->region_assign_count);
···
 	.ssr_name = "lpass",
 	.sysmon_name = "adsp",
 	.ssctl_id = 0x14,
+	.smem_host_id = 2,
 };
 
 static const struct adsp_data sm8550_cdsp_resource = {
···
 	.ssr_name = "cdsp",
 	.sysmon_name = "cdsp",
 	.ssctl_id = 0x17,
+	.smem_host_id = 5,
 };
 
 static const struct adsp_data sm8550_mpss_resource = {
···
 	.ssr_name = "mpss",
 	.sysmon_name = "modem",
 	.ssctl_id = 0x12,
+	.smem_host_id = 1,
 	.region_assign_idx = 2,
 	.region_assign_count = 1,
 	.region_assign_vmid = QCOM_SCM_VMID_MSS_MSA,
···
 	.ssr_name = "cdsp",
 	.sysmon_name = "cdsp",
 	.ssctl_id = 0x17,
+	.smem_host_id = 5,
 	.region_assign_idx = 2,
 	.region_assign_count = 1,
 	.region_assign_shared = true,
···
 	.ssr_name = "mpss",
 	.sysmon_name = "modem",
 	.ssctl_id = 0x12,
+	.smem_host_id = 1,
 	.region_assign_idx = 2,
 	.region_assign_count = 3,
 	.region_assign_vmid = QCOM_SCM_VMID_MSS_MSA,