[PATCH 2/4] crypto: ccp: Add external API interface for PSP module initialization

[Ashish Kalra <Ashish.Kalra@xxxxxxx>]

From: Sean Christopherson <seanjc@xxxxxxxxxx>

Add a new external API interface for PSP module initialization which
allows PSP SEV driver to be initialized explicitly before proceeding
with SEV/SNP initialization with KVM if KVM is built-in as the
dependency between modules is not supported/handled by the initcall
infrastructure and the dependent PSP module is not implicitly loaded
before KVM module if KVM module is built-in.

Co-developed-by: Ashish Kalra <ashish.kalra@xxxxxxx>
Signed-off-by: Ashish Kalra <ashish.kalra@xxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 drivers/crypto/ccp/sp-dev.c | 12 ++++++++++++
 drivers/crypto/ccp/sp-dev.h |  1 +
 include/linux/psp-sev.h     | 11 +++++++++++
 3 files changed, 24 insertions(+)

diff --git a/drivers/crypto/ccp/sp-dev.c b/drivers/crypto/ccp/sp-dev.c
index 7eb3e4668286..a0cdc03984cb 100644
--- a/drivers/crypto/ccp/sp-dev.c
+++ b/drivers/crypto/ccp/sp-dev.c
@@ -253,8 +253,12 @@ struct sp_device *sp_get_psp_master_device(void)
 static int __init sp_mod_init(void)
 {
 #ifdef CONFIG_X86
+	static bool initialized;
 	int ret;
 
+	if (initialized)
+		return 0;
+
 	ret = sp_pci_init();
 	if (ret)
 		return ret;
@@ -263,6 +267,7 @@ static int __init sp_mod_init(void)
 	psp_pci_init();
 #endif
 
+	initialized = true;
 	return 0;
 #endif
 
@@ -279,6 +284,13 @@ static int __init sp_mod_init(void)
 	return -ENODEV;
 }
 
+#if IS_BUILTIN(CONFIG_KVM_AMD) && IS_ENABLED(CONFIG_KVM_AMD_SEV)
+int __init sev_module_init(void)
+{
+	return sp_mod_init();
+}
+#endif
+
 static void __exit sp_mod_exit(void)
 {
 #ifdef CONFIG_X86
diff --git a/drivers/crypto/ccp/sp-dev.h b/drivers/crypto/ccp/sp-dev.h
index 6f9d7063257d..3f5f7491bec1 100644
--- a/drivers/crypto/ccp/sp-dev.h
+++ b/drivers/crypto/ccp/sp-dev.h
@@ -148,6 +148,7 @@ int sp_request_psp_irq(struct sp_device *sp, irq_handler_t handler,
 		       const char *name, void *data);
 void sp_free_psp_irq(struct sp_device *sp, void *data);
 struct sp_device *sp_get_psp_master_device(void);
+int __init sev_module_init(void);
 
 #ifdef CONFIG_CRYPTO_DEV_SP_CCP
 
diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
index 903ddfea8585..1cf197fca93d 100644
--- a/include/linux/psp-sev.h
+++ b/include/linux/psp-sev.h
@@ -814,6 +814,15 @@ struct sev_data_snp_commit {
 
 #ifdef CONFIG_CRYPTO_DEV_SP_PSP
 
+/**
+ * sev_module_init - perform PSP module initialization
+ *
+ * Returns:
+ * 0 if the PSP module is successfully initialized
+ * -%ENODEV    if the PSP module initialization fails
+ */
+int __init sev_module_init(void);
+
 /**
  * sev_platform_init - perform SEV INIT command
  *
@@ -948,6 +957,8 @@ void snp_free_firmware_page(void *addr);
 
 #else	/* !CONFIG_CRYPTO_DEV_SP_PSP */
 
+static inline int __init sev_module_init(void) { return -ENODEV }
+
 static inline int
 sev_platform_status(struct sev_user_data_status *status, int *error) { return -ENODEV; }
 
-- 
2.34.1