[PATCH V4 4/5] crypto: ccp - Add psp_init_on_probe module parameter

[Peter Gonda]

Add psp_init_on_probe module parameter that allows for skipping the
PSP's SEV platform initialization during module init. User may decouple
module init from PSP init due to use of the INIT_EX support in upcoming
patch which allows for users to save PSP's internal state to file. The
file may be unavailable at module init.

Also moves the PSP ABI version log message to after successful PSP init
instead of module init in case this new parameter is used.

Signed-off-by: Peter Gonda <pgonda@xxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: Brijesh Singh <brijesh.singh@xxxxxxx>
Cc: Marc Orr <marcorr@xxxxxxxxxx>
Cc: Joerg Roedel <jroedel@xxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: John Allen <john.allen@xxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
 drivers/crypto/ccp/sev-dev.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 8e388f6c9b05..ee9f194d460e 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -43,6 +43,10 @@ static int psp_probe_timeout = 5;
 module_param(psp_probe_timeout, int, 0644);
 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
 
+static bool psp_init_on_probe = true;
+module_param(psp_init_on_probe, bool, 0444);
+MODULE_PARM_DESC(psp_init_on_probe, "  if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it");
+
 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
@@ -305,7 +309,10 @@ static int __sev_platform_init_locked(int *error)
 
 	dev_dbg(sev->dev, "SEV firmware initialized\n");
 
-	return rc;
+	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
+		 sev->api_minor, sev->build);
+
+	return 0;
 }
 
 int sev_platform_init(int *error)
@@ -1110,16 +1117,14 @@ void sev_pci_init(void)
 		dev_warn(sev->dev,
 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
 
+	if (!psp_init_on_probe)
+		return;
+
 	/* Initialize the platform */
 	rc = sev_platform_init(&error);
-	if (rc) {
+	if (rc)
 		dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n",
 			error, rc);
-		return;
-	}
-
-	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
-		 sev->api_minor, sev->build);
 
 	return;
 
-- 
2.34.0.rc1.387.gb447b232ab-goog