[PATCH AUTOSEL 6.10 060/121] soc: qcom: smem: Add qcom_smem_bust_hwspin_lock_by_host()

[PATCH AUTOSEL 6.10 060/121] soc: qcom: smem: Add qcom_smem_bust_hwspin_lock_by_host()

[Sasha Levin]

From: Chris Lew <quic_clew@quicinc.com>

[ 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@quicinc.com>
Reviewed-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Link: https://lore.kernel.org/r/20240529-hwspinlock-bust-v3-3-c8b924ffa5a2@quicinc.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 7191fa0c087f2..50039e983ebaa 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

[PATCH AUTOSEL 6.10 061/121] remoteproc: qcom_q6v5_pas: Add hwspinlock bust on stop

[Sasha Levin]

From: Richard Maina <quic_rmaina@quicinc.com>

[ Upstream commit 568b13b65078e2b557ccf47674a354cecd1db641 ]

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 <quic_rmaina@quicinc.com>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Chris Lew <quic_clew@quicinc.com>
Link: https://lore.kernel.org/r/20240529-hwspinlock-bust-v3-4-c8b924ffa5a2@quicinc.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/remoteproc/qcom_q6v5_pas.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c
index 54d8005d40a34..8458bcfe9e19e 100644
--- a/drivers/remoteproc/qcom_q6v5_pas.c
+++ b/drivers/remoteproc/qcom_q6v5_pas.c
@@ -52,6 +52,7 @@ struct adsp_data {
 	const char *ssr_name;
 	const char *sysmon_name;
 	int ssctl_id;
+	unsigned int smem_host_id;
 
 	int region_assign_idx;
 	int region_assign_count;
@@ -81,6 +82,7 @@ struct qcom_adsp {
 	int lite_pas_id;
 	unsigned int minidump_id;
 	int crash_reason_smem;
+	unsigned int smem_host_id;
 	bool decrypt_shutdown;
 	const char *info_name;
 
@@ -399,6 +401,9 @@ static int adsp_stop(struct rproc *rproc)
 	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;
 }
 
@@ -727,6 +732,7 @@ static int adsp_probe(struct platform_device *pdev)
 	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);
@@ -1196,6 +1202,7 @@ static const struct adsp_data sm8550_adsp_resource = {
 	.ssr_name = "lpass",
 	.sysmon_name = "adsp",
 	.ssctl_id = 0x14,
+	.smem_host_id = 2,
 };
 
 static const struct adsp_data sm8550_cdsp_resource = {
@@ -1216,6 +1223,7 @@ 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 = {
@@ -1236,6 +1244,7 @@ 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,
@@ -1275,6 +1284,7 @@ static const struct adsp_data sm8650_cdsp_resource = {
 	.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,
@@ -1299,6 +1309,7 @@ static const struct adsp_data sm8650_mpss_resource = {
 	.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,
-- 
2.43.0