[PATCH 1/3] crypto: ccp - Validate that platform access mailbox registers are declared

[Mario Limonciello <mario.limonciello@amd.com>]

Some platforms might support platform access doorbell but not mailbox.
Add an extra guard to ensure this doesn't cause accesses to wrong ranges
if a consumer calls psp_send_platform_access_msg().

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 drivers/crypto/ccp/platform-access.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/crypto/ccp/platform-access.c b/drivers/crypto/ccp/platform-access.c
index 939c924fc383..94367bc49e35 100644
--- a/drivers/crypto/ccp/platform-access.c
+++ b/drivers/crypto/ccp/platform-access.c
@@ -67,6 +67,11 @@ int psp_send_platform_access_msg(enum psp_platform_access_msg msg,
 		return -ENODEV;
 
 	pa_dev = psp->platform_access_data;
+
+	if (!pa_dev->vdata->cmdresp_reg || !pa_dev->vdata->cmdbuff_addr_lo_reg ||
+	    !pa_dev->vdata->cmdbuff_addr_hi_reg)
+		return -ENODEV;
+
 	cmd = psp->io_regs + pa_dev->vdata->cmdresp_reg;
 	lo = psp->io_regs + pa_dev->vdata->cmdbuff_addr_lo_reg;
 	hi = psp->io_regs + pa_dev->vdata->cmdbuff_addr_hi_reg;
-- 
2.34.1