3 files changed, 53 insertions, 54 deletions

diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
index f63b716be5b0..26cd0458aacd 100644
--- a/drivers/firmware/qcom/qcom_scm.c
+++ b/drivers/firmware/qcom/qcom_scm.c
@@ -1603,7 +1603,13 @@ bool qcom_scm_lmh_dcvsh_available(void)
 }
 EXPORT_SYMBOL_GPL(qcom_scm_lmh_dcvsh_available);
 
-int qcom_scm_shm_bridge_enable(void)
+/*
+ * This is only supposed to be called once by the TZMem module. It takes the
+ * SCM struct device as argument and uses it to pass the call as at the time
+ * the SHM Bridge is enabled, the SCM is not yet fully set up and doesn't
+ * accept global user calls. Don't try to use the __scm pointer here.
+ */
+int qcom_scm_shm_bridge_enable(struct device *scm_dev)
 {
 	int ret;
 
@@ -1615,11 +1621,11 @@ int qcom_scm_shm_bridge_enable(void)
 
 	struct qcom_scm_res res;
 
-	if (!__qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_MP,
+	if (!__qcom_scm_is_call_available(scm_dev, QCOM_SCM_SVC_MP,
 					  QCOM_SCM_MP_SHM_BRIDGE_ENABLE))
 		return -EOPNOTSUPP;
 
-	ret = qcom_scm_call(__scm->dev, &desc, &res);
+	ret = qcom_scm_call(scm_dev, &desc, &res);
 
 	if (ret)
 		return ret;
@@ -1631,7 +1637,7 @@ int qcom_scm_shm_bridge_enable(void)
 }
 EXPORT_SYMBOL_GPL(qcom_scm_shm_bridge_enable);
 
-int qcom_scm_shm_bridge_create(struct device *dev, u64 pfn_and_ns_perm_flags,
+int qcom_scm_shm_bridge_create(u64 pfn_and_ns_perm_flags,
 			       u64 ipfn_and_s_perm_flags, u64 size_and_flags,
 			       u64 ns_vmids, u64 *handle)
 {
@@ -1659,7 +1665,7 @@ int qcom_scm_shm_bridge_create(struct device *dev, u64 pfn_and_ns_perm_flags,
 }
 EXPORT_SYMBOL_GPL(qcom_scm_shm_bridge_create);
 
-int qcom_scm_shm_bridge_delete(struct device *dev, u64 handle)
+int qcom_scm_shm_bridge_delete(u64 handle)
 {
 	struct qcom_scm_desc desc = {
 		.svc = QCOM_SCM_SVC_MP,
@@ -2250,24 +2256,47 @@ static int qcom_scm_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	/* Paired with smp_load_acquire() in qcom_scm_is_available(). */
-	smp_store_release(&__scm, scm);
+	ret = of_reserved_mem_device_init(scm->dev);
+	if (ret && ret != -ENODEV)
+		return dev_err_probe(scm->dev, ret,
+				     "Failed to setup the reserved memory region for TZ mem\n");
+
+	ret = qcom_tzmem_enable(scm->dev);
+	if (ret)
+		return dev_err_probe(scm->dev, ret,
+				     "Failed to enable the TrustZone memory allocator\n");
+
+	memset(&pool_config, 0, sizeof(pool_config));
+	pool_config.initial_size = 0;
+	pool_config.policy = QCOM_TZMEM_POLICY_ON_DEMAND;
+	pool_config.max_size = SZ_256K;
+
+	scm->mempool = devm_qcom_tzmem_pool_new(scm->dev, &pool_config);
+	if (IS_ERR(scm->mempool))
+		return dev_err_probe(scm->dev, PTR_ERR(scm->mempool),
+				     "Failed to create the SCM memory pool\n");
 
 	irq = platform_get_irq_optional(pdev, 0);
 	if (irq < 0) {
-		if (irq != -ENXIO) {
-			ret = irq;
-			goto err;
-		}
+		if (irq != -ENXIO)
+			return irq;
 	} else {
-		ret = devm_request_threaded_irq(__scm->dev, irq, NULL, qcom_scm_irq_handler,
-						IRQF_ONESHOT, "qcom-scm", __scm);
-		if (ret < 0) {
-			dev_err_probe(scm->dev, ret, "Failed to request qcom-scm irq\n");
-			goto err;
-		}
+		ret = devm_request_threaded_irq(scm->dev, irq, NULL, qcom_scm_irq_handler,
+						IRQF_ONESHOT, "qcom-scm", scm);
+		if (ret < 0)
+			return dev_err_probe(scm->dev, ret,
+					     "Failed to request qcom-scm irq\n");
 	}
 
+	/*
+	 * Paired with smp_load_acquire() in qcom_scm_is_available().
+	 *
+	 * This marks the SCM API as ready to accept user calls and can only
+	 * be called after the TrustZone memory pool is initialized and the
+	 * waitqueue interrupt requested.
+	 */
+	smp_store_release(&__scm, scm);
+
 	__get_convention();
 
 	/*
@@ -2283,32 +2312,6 @@ static int qcom_scm_probe(struct platform_device *pdev)
 	if (of_property_read_bool(pdev->dev.of_node, "qcom,sdi-enabled") || !download_mode)
 		qcom_scm_disable_sdi();
 
-	ret = of_reserved_mem_device_init(__scm->dev);
-	if (ret && ret != -ENODEV) {
-		dev_err_probe(__scm->dev, ret,
-			      "Failed to setup the reserved memory region for TZ mem\n");
-		goto err;
-	}
-
-	ret = qcom_tzmem_enable(__scm->dev);
-	if (ret) {
-		dev_err_probe(__scm->dev, ret,
-			      "Failed to enable the TrustZone memory allocator\n");
-		goto err;
-	}
-
-	memset(&pool_config, 0, sizeof(pool_config));
-	pool_config.initial_size = 0;
-	pool_config.policy = QCOM_TZMEM_POLICY_ON_DEMAND;
-	pool_config.max_size = SZ_256K;
-
-	__scm->mempool = devm_qcom_tzmem_pool_new(__scm->dev, &pool_config);
-	if (IS_ERR(__scm->mempool)) {
-		ret = dev_err_probe(__scm->dev, PTR_ERR(__scm->mempool),
-				    "Failed to create the SCM memory pool\n");
-		goto err;
-	}
-
 	/*
 	 * Initialize the QSEECOM interface.
 	 *
@@ -2323,12 +2326,6 @@ static int qcom_scm_probe(struct platform_device *pdev)
 	WARN(ret < 0, "failed to initialize qseecom: %d\n", ret);
 
 	return 0;
-
-err:
-	/* Paired with smp_load_acquire() in qcom_scm_is_available(). */
-	smp_store_release(&__scm, NULL);
-
-	return ret;
 }
 
 static void qcom_scm_shutdown(struct platform_device *pdev)
diff --git a/drivers/firmware/qcom/qcom_scm.h b/drivers/firmware/qcom/qcom_scm.h
index 3133d826f5fa..0e8dd838099e 100644
--- a/drivers/firmware/qcom/qcom_scm.h
+++ b/drivers/firmware/qcom/qcom_scm.h
@@ -83,6 +83,7 @@ int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
 		    struct qcom_scm_res *res);
 
 struct qcom_tzmem_pool *qcom_scm_get_tzmem_pool(void);
+int qcom_scm_shm_bridge_enable(struct device *scm_dev);
 
 #define QCOM_SCM_SVC_BOOT		0x01
 #define QCOM_SCM_BOOT_SET_ADDR		0x01
diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c
index 94196ad87105..ea0a35355657 100644
--- a/drivers/firmware/qcom/qcom_tzmem.c
+++ b/drivers/firmware/qcom/qcom_tzmem.c
@@ -20,6 +20,7 @@
 #include <linux/spinlock.h>
 #include <linux/types.h>
 
+#include "qcom_scm.h"
 #include "qcom_tzmem.h"
 
 struct qcom_tzmem_area {
@@ -94,7 +95,7 @@ static int qcom_tzmem_init(void)
 			goto notsupp;
 	}
 
-	ret = qcom_scm_shm_bridge_enable();
+	ret = qcom_scm_shm_bridge_enable(qcom_tzmem_dev);
 	if (ret == -EOPNOTSUPP)
 		goto notsupp;
 
@@ -124,9 +125,9 @@ static int qcom_tzmem_init_area(struct qcom_tzmem_area *area)
 	if (!handle)
 		return -ENOMEM;
 
-	ret = qcom_scm_shm_bridge_create(qcom_tzmem_dev, pfn_and_ns_perm,
-					 ipfn_and_s_perm, size_and_flags,
-					 QCOM_SCM_VMID_HLOS, handle);
+	ret = qcom_scm_shm_bridge_create(pfn_and_ns_perm, ipfn_and_s_perm,
+					 size_and_flags, QCOM_SCM_VMID_HLOS,
+					 handle);
 	if (ret)
 		return ret;
 
@@ -142,7 +143,7 @@ static void qcom_tzmem_cleanup_area(struct qcom_tzmem_area *area)
 	if (!qcom_tzmem_using_shm_bridge)
 		return;
 
-	qcom_scm_shm_bridge_delete(qcom_tzmem_dev, *handle);
+	qcom_scm_shm_bridge_delete(*handle);
 	kfree(handle);
 }