diff options
| -rw-r--r-- | drivers/crypto/ccp/psp-dev.c | 46 |
1 files changed, 41 insertions, 5 deletions
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c index 2cd7a5ea4156..3bedf7254a97 100644 --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -53,7 +53,7 @@ static irqreturn_t psp_irq_handler(int irq, void *data) return IRQ_HANDLED; } -static int psp_check_sev_support(struct psp_device *psp) +static unsigned int psp_get_capability(struct psp_device *psp) { unsigned int val = ioread32(psp->io_regs + psp->vdata->feature_reg); @@ -66,11 +66,17 @@ static int psp_check_sev_support(struct psp_device *psp) */ if (val == 0xffffffff) { dev_notice(psp->dev, "psp: unable to access the device: you might be running a broken BIOS.\n"); - return -ENODEV; + return 0; } - if (!(val & 1)) { - /* Device does not support the SEV feature */ + return val; +} + +static int psp_check_sev_support(struct psp_device *psp, + unsigned int capability) +{ + /* Check if device supports SEV feature */ + if (!(capability & 1)) { dev_dbg(psp->dev, "psp does not support SEV\n"); return -ENODEV; } @@ -78,10 +84,36 @@ static int psp_check_sev_support(struct psp_device *psp) return 0; } +static int psp_check_tee_support(struct psp_device *psp, + unsigned int capability) +{ + /* Check if device supports TEE feature */ + if (!(capability & 2)) { + dev_dbg(psp->dev, "psp does not support TEE\n"); + return -ENODEV; + } + + return 0; +} + +static int psp_check_support(struct psp_device *psp, + unsigned int capability) +{ + int sev_support = psp_check_sev_support(psp, capability); + int tee_support = psp_check_tee_support(psp, capability); + + /* Return error if device neither supports SEV nor TEE */ + if (sev_support && tee_support) + return -ENODEV; + + return 0; +} + int psp_dev_init(struct sp_device *sp) { struct device *dev = sp->dev; struct psp_device *psp; + unsigned int capability; int ret; ret = -ENOMEM; @@ -100,7 +132,11 @@ int psp_dev_init(struct sp_device *sp) psp->io_regs = sp->io_map; - ret = psp_check_sev_support(psp); + capability = psp_get_capability(psp); + if (!capability) + goto e_disable; + + ret = psp_check_support(psp, capability); if (ret) goto e_disable; |