diff mbox series

[v3,4/5] tpm_crb: add support for the Arm FF-A start method

Message ID 20250214002745.878890-5-stuart.yoder@arm.com (mailing list archive)
State New
Headers show
Series Add support for the TPM FF-A start method | expand

Commit Message

Stuart Yoder Feb. 14, 2025, 12:27 a.m. UTC 
The TCG ACPI spec v1.4 defines a start method for the
TPMs implemented with the Arm CRB over FF-A ABI.

Add support for the FF-A start method, and use interfaces
provided by the ffa_crb driver to interact with the
FF-A based TPM.

Signed-off-by: Stuart Yoder <stuart.yoder@arm.com>
---
 drivers/char/tpm/tpm_crb.c | 65 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 64 insertions(+), 1 deletion(-)

Comments

Jarkko Sakkinen Feb. 14, 2025, 8:20 a.m. UTC | #1 
On Thu, Feb 13, 2025 at 06:27:44PM -0600, Stuart Yoder wrote:
> The TCG ACPI spec v1.4 defines a start method for the
> TPMs implemented with the Arm CRB over FF-A ABI.
> 
> Add support for the FF-A start method, and use interfaces
> provided by the ffa_crb driver to interact with the
> FF-A based TPM.
> 
> Signed-off-by: Stuart Yoder <stuart.yoder@arm.com>
> ---
>  drivers/char/tpm/tpm_crb.c | 65 +++++++++++++++++++++++++++++++++++++-
>  1 file changed, 64 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
> index d696226906a2..486be5ea82bb 100644
> --- a/drivers/char/tpm/tpm_crb.c
> +++ b/drivers/char/tpm/tpm_crb.c
> @@ -19,6 +19,7 @@
>  #ifdef CONFIG_ARM64
>  #include <linux/arm-smccc.h>
>  #endif
> +#include "tpm_crb_ffa.h"
>  #include "tpm.h"
>  
>  #define ACPI_SIG_TPM2 "TPM2"
> @@ -100,6 +101,8 @@ struct crb_priv {
>  	u32 smc_func_id;
>  	u32 __iomem *pluton_start_addr;
>  	u32 __iomem *pluton_reply_addr;
> +	u8 ffa_flags;
> +	u8 ffa_attributes;
>  };
>  
>  struct tpm2_crb_smc {
> @@ -110,6 +113,14 @@ struct tpm2_crb_smc {
>  	u32 smc_func_id;
>  };
>  
> +/* CRB over FFA start method parameters in TCG2 ACPI table */
> +struct tpm2_crb_ffa {
> +	u8 flags;
> +	u8 attributes;
> +	u16 partition_id;
> +	u8 reserved[8];
> +};
> +
>  struct tpm2_crb_pluton {
>  	u64 start_addr;
>  	u64 reply_addr;
> @@ -119,7 +130,8 @@ static inline bool tpm_crb_has_idle(u32 start_method)
>  {
>  	if ((start_method == ACPI_TPM2_START_METHOD) ||
>  	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
> -	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
> +	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) ||
> +	    (start_method == ACPI_TPM2_CRB_WITH_ARM_FFA))

Now that we have a chance, let's rip of the parentheses clutter.

>  		return false;
>  	else
>  		return true;
> @@ -261,6 +273,7 @@ static int crb_cmd_ready(struct tpm_chip *chip)
>  static int __crb_request_locality(struct device *dev,
>  				  struct crb_priv *priv, int loc)
>  {
> +	int rc;
>  	u32 value = CRB_LOC_STATE_LOC_ASSIGNED |
>  		    CRB_LOC_STATE_TPM_REG_VALID_STS;

Declaration order + put to the same line.

>  
> @@ -268,6 +281,13 @@ static int __crb_request_locality(struct device *dev,
>  		return 0;
>  
>  	iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl);
> +
> +	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
> +		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc);
> +		if (rc)
> +			return rc;
> +	}
> +
>  	if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, value, value,
>  				 TPM2_TIMEOUT_C)) {
>  		dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
> @@ -287,6 +307,7 @@ static int crb_request_locality(struct tpm_chip *chip, int loc)
>  static int __crb_relinquish_locality(struct device *dev,
>  				     struct crb_priv *priv, int loc)
>  {
> +	int rc;
>  	u32 mask = CRB_LOC_STATE_LOC_ASSIGNED |
>  		   CRB_LOC_STATE_TPM_REG_VALID_STS;
>  	u32 value = CRB_LOC_STATE_TPM_REG_VALID_STS;
> @@ -295,6 +316,13 @@ static int __crb_relinquish_locality(struct device *dev,
>  		return 0;
>  
>  	iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl);
> +
> +	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
> +		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc);
> +		if (rc)
> +			return rc;
> +	}
> +
>  	if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, mask, value,
>  				 TPM2_TIMEOUT_C)) {
>  		dev_warn(dev, "TPM_LOC_STATE_x.Relinquish timed out\n");
> @@ -443,6 +471,11 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
>  		rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id);
>  	}
>  
> +	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
> +		iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> +		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality);
> +	}
> +
>  	if (rc)
>  		return rc;
>  
> @@ -451,6 +484,7 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
>  
>  static void crb_cancel(struct tpm_chip *chip)
>  {
> +	int rc;
>  	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
>  
>  	iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel);
> @@ -459,6 +493,12 @@ static void crb_cancel(struct tpm_chip *chip)
>  	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) &&
>  	     crb_do_acpi_start(chip))
>  		dev_err(&chip->dev, "ACPI Start failed\n");
> +
> +	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
> +		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality);
> +		if (rc)
> +			dev_err(&chip->dev, "FF-A Start failed\n");
> +	}
>  }
>  
>  static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
> @@ -616,6 +656,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
>  	 * stuff that puts the control area outside the ACPI IO region.
>  	 */
>  	if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
> +	    (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) ||
>  	    (priv->sm == ACPI_TPM2_MEMORY_MAPPED)) {

Ditto.

>  		if (iores &&
>  		    buf->control_address == iores->start +
> @@ -737,6 +778,7 @@ static int crb_acpi_add(struct acpi_device *device)
>  	struct tpm_chip *chip;
>  	struct device *dev = &device->dev;
>  	struct tpm2_crb_smc *crb_smc;
> +	struct tpm2_crb_ffa *crb_ffa;
>  	struct tpm2_crb_pluton *crb_pluton;
>  	acpi_status status;
>  	u32 sm;
> @@ -775,6 +817,27 @@ static int crb_acpi_add(struct acpi_device *device)
>  		priv->smc_func_id = crb_smc->smc_func_id;
>  	}
>  
> +	if (sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
> +		if (buf->header.length < (sizeof(*buf) + sizeof(*crb_ffa))) {
> +			dev_err(dev,
> +				FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n",
> +				buf->header.length,
> +				ACPI_TPM2_CRB_WITH_ARM_FFA);
> +			rc = -EINVAL;
> +			goto out;
> +		}
> +		crb_ffa = ACPI_ADD_PTR(struct tpm2_crb_ffa, buf, sizeof(*buf));
> +		priv->ffa_flags = crb_ffa->flags;
> +		priv->ffa_attributes = crb_ffa->attributes;
> +		rc = tpm_crb_ffa_init();
> +		if (rc) {
> +			if (rc == -ENOENT) {  // FF-A driver is not available yet
> +				rc = -EPROBE_DEFER;
> +			}
> +			goto out;
> +		}
> +	}
> +
>  	if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) {
>  		if (buf->header.length < (sizeof(*buf) + sizeof(*crb_pluton))) {
>  			dev_err(dev,
> -- 
> 2.34.1
> 

BR, Jarkko
Stuart Yoder Feb. 17, 2025, 3:56 p.m. UTC | #2 
>> @@ -119,7 +130,8 @@ static inline bool tpm_crb_has_idle(u32 start_method)
>>   {
>>   	if ((start_method == ACPI_TPM2_START_METHOD) ||
>>   	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
>> -	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
>> +	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) ||
>> +	    (start_method == ACPI_TPM2_CRB_WITH_ARM_FFA))
> 
> Now that we have a chance, let's rip of the parentheses clutter.

Will do that throughout.

>>   		return false;
>>   	else
>>   		return true;
>> @@ -261,6 +273,7 @@ static int crb_cmd_ready(struct tpm_chip *chip)
>>   static int __crb_request_locality(struct device *dev,
>>   				  struct crb_priv *priv, int loc)
>>   {
>> +	int rc;
>>   	u32 value = CRB_LOC_STATE_LOC_ASSIGNED |
>>   		    CRB_LOC_STATE_TPM_REG_VALID_STS;
> 
> Declaration order + put to the same line.

Ack.

Thanks,
Stuart
diff mbox series

Patch

diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index d696226906a2..486be5ea82bb 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -19,6 +19,7 @@ 
 #ifdef CONFIG_ARM64
 #include <linux/arm-smccc.h>
 #endif
+#include "tpm_crb_ffa.h"
 #include "tpm.h"
 
 #define ACPI_SIG_TPM2 "TPM2"
@@ -100,6 +101,8 @@  struct crb_priv {
 	u32 smc_func_id;
 	u32 __iomem *pluton_start_addr;
 	u32 __iomem *pluton_reply_addr;
+	u8 ffa_flags;
+	u8 ffa_attributes;
 };
 
 struct tpm2_crb_smc {
@@ -110,6 +113,14 @@  struct tpm2_crb_smc {
 	u32 smc_func_id;
 };
 
+/* CRB over FFA start method parameters in TCG2 ACPI table */
+struct tpm2_crb_ffa {
+	u8 flags;
+	u8 attributes;
+	u16 partition_id;
+	u8 reserved[8];
+};
+
 struct tpm2_crb_pluton {
 	u64 start_addr;
 	u64 reply_addr;
@@ -119,7 +130,8 @@  static inline bool tpm_crb_has_idle(u32 start_method)
 {
 	if ((start_method == ACPI_TPM2_START_METHOD) ||
 	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
-	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
+	    (start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) ||
+	    (start_method == ACPI_TPM2_CRB_WITH_ARM_FFA))
 		return false;
 	else
 		return true;
@@ -261,6 +273,7 @@  static int crb_cmd_ready(struct tpm_chip *chip)
 static int __crb_request_locality(struct device *dev,
 				  struct crb_priv *priv, int loc)
 {
+	int rc;
 	u32 value = CRB_LOC_STATE_LOC_ASSIGNED |
 		    CRB_LOC_STATE_TPM_REG_VALID_STS;
 
@@ -268,6 +281,13 @@  static int __crb_request_locality(struct device *dev,
 		return 0;
 
 	iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl);
+
+	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
+		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc);
+		if (rc)
+			return rc;
+	}
+
 	if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, value, value,
 				 TPM2_TIMEOUT_C)) {
 		dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
@@ -287,6 +307,7 @@  static int crb_request_locality(struct tpm_chip *chip, int loc)
 static int __crb_relinquish_locality(struct device *dev,
 				     struct crb_priv *priv, int loc)
 {
+	int rc;
 	u32 mask = CRB_LOC_STATE_LOC_ASSIGNED |
 		   CRB_LOC_STATE_TPM_REG_VALID_STS;
 	u32 value = CRB_LOC_STATE_TPM_REG_VALID_STS;
@@ -295,6 +316,13 @@  static int __crb_relinquish_locality(struct device *dev,
 		return 0;
 
 	iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl);
+
+	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
+		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc);
+		if (rc)
+			return rc;
+	}
+
 	if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, mask, value,
 				 TPM2_TIMEOUT_C)) {
 		dev_warn(dev, "TPM_LOC_STATE_x.Relinquish timed out\n");
@@ -443,6 +471,11 @@  static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
 		rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id);
 	}
 
+	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
+		iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
+		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality);
+	}
+
 	if (rc)
 		return rc;
 
@@ -451,6 +484,7 @@  static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
 
 static void crb_cancel(struct tpm_chip *chip)
 {
+	int rc;
 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
 
 	iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel);
@@ -459,6 +493,12 @@  static void crb_cancel(struct tpm_chip *chip)
 	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) &&
 	     crb_do_acpi_start(chip))
 		dev_err(&chip->dev, "ACPI Start failed\n");
+
+	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
+		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality);
+		if (rc)
+			dev_err(&chip->dev, "FF-A Start failed\n");
+	}
 }
 
 static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
@@ -616,6 +656,7 @@  static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
 	 * stuff that puts the control area outside the ACPI IO region.
 	 */
 	if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
+	    (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) ||
 	    (priv->sm == ACPI_TPM2_MEMORY_MAPPED)) {
 		if (iores &&
 		    buf->control_address == iores->start +
@@ -737,6 +778,7 @@  static int crb_acpi_add(struct acpi_device *device)
 	struct tpm_chip *chip;
 	struct device *dev = &device->dev;
 	struct tpm2_crb_smc *crb_smc;
+	struct tpm2_crb_ffa *crb_ffa;
 	struct tpm2_crb_pluton *crb_pluton;
 	acpi_status status;
 	u32 sm;
@@ -775,6 +817,27 @@  static int crb_acpi_add(struct acpi_device *device)
 		priv->smc_func_id = crb_smc->smc_func_id;
 	}
 
+	if (sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
+		if (buf->header.length < (sizeof(*buf) + sizeof(*crb_ffa))) {
+			dev_err(dev,
+				FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n",
+				buf->header.length,
+				ACPI_TPM2_CRB_WITH_ARM_FFA);
+			rc = -EINVAL;
+			goto out;
+		}
+		crb_ffa = ACPI_ADD_PTR(struct tpm2_crb_ffa, buf, sizeof(*buf));
+		priv->ffa_flags = crb_ffa->flags;
+		priv->ffa_attributes = crb_ffa->attributes;
+		rc = tpm_crb_ffa_init();
+		if (rc) {
+			if (rc == -ENOENT) {  // FF-A driver is not available yet
+				rc = -EPROBE_DEFER;
+			}
+			goto out;
+		}
+	}
+
 	if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) {
 		if (buf->header.length < (sizeof(*buf) + sizeof(*crb_pluton))) {
 			dev_err(dev,