security/tpm/: turn tis_{init,open} into tis_probe

Init was always followed by open and after successful initialization we
need only send-receive function, which is now returned by tis_probe on
success further reducing number of functions to export from drivers.

Change-Id: Ib4ce35ada24e3959ea1a518c29d431b4ae123809
Ticket: https://ticket.coreboot.org/issues/433
Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/68991
Reviewed-by: Julius Werner <jwerner@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/drivers/crb/tis.c

@@ -14,8 +14,6 @@
 #include "tpm.h"
 #include "chip.h"
 
-static unsigned int tpm_is_open;
-
 static const struct {
 	uint16_t vid;
 	uint16_t did;
@@ -35,41 +33,8 @@ static const char *tis_get_dev_name(struct tpm2_info *info)
 	return "Unknown";
 }
 
-int tis_open(void)
+static int crb_tpm_sendrecv(const uint8_t *sendbuf, size_t sbuf_size, uint8_t *recvbuf,
-{
+			    size_t *rbuf_len)
-	if (tpm_is_open) {
-		printk(BIOS_ERR, "%s called twice.\n", __func__);
-		return -1;
-	}
-
-	if (CONFIG(HAVE_INTEL_PTT)) {
-		if (!ptt_active()) {
-			printk(BIOS_ERR, "%s: Intel PTT is not active.\n", __func__);
-			return -1;
-		}
-		printk(BIOS_DEBUG, "%s: Intel PTT is active.\n", __func__);
-	}
-
-	return 0;
-}
-
-int tis_init(void)
-{
-	struct tpm2_info info;
-
-	// Wake TPM up (if necessary)
-	if (tpm2_init() != 0)
-		return -1;
-
-	tpm2_get_info(&info);
-
-	printk(BIOS_INFO, "Initialized TPM device %s revision %d\n", tis_get_dev_name(&info),
-	       info.revision);
-
-	return 0;
-}
-
-int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size, uint8_t *recvbuf, size_t *rbuf_len)
 {
 	int len = tpm2_process_command(sendbuf, sbuf_size, recvbuf, *rbuf_len);
 
@@ -81,6 +46,30 @@ int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size, uint8_t *recvbuf, siz
 	return 0;
 }
 
+tis_sendrecv_fn tis_probe(void)
+{
+	struct tpm2_info info;
+
+	/* Wake TPM up (if necessary) */
+	if (tpm2_init() != 0)
+		return NULL;
+
+	tpm2_get_info(&info);
+
+	printk(BIOS_INFO, "Initialized TPM device %s revision %d\n", tis_get_dev_name(&info),
+	       info.revision);
+
+	if (CONFIG(HAVE_INTEL_PTT)) {
+		if (!ptt_active()) {
+			printk(BIOS_ERR, "%s: Intel PTT is not active.\n", __func__);
+			return NULL;
+		}
+		printk(BIOS_DEBUG, "%s: Intel PTT is active.\n", __func__);
+	}
+
+	return &crb_tpm_sendrecv;
+}
+
 static void crb_tpm_fill_ssdt(const struct device *dev)
 {
 	const char *path = acpi_device_path(dev);

src/drivers/i2c/tpm/cr50.c

@@ -484,7 +484,6 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned int bus, uint32_t dev_addr)
                 cr50_set_board_cfg();
 	}
 
-	chip->is_open = 1;
 	return 0;
 }
 

src/drivers/i2c/tpm/tis.c

@@ -19,32 +19,6 @@ static struct tpm_chip chip;
 #define TPM_CMD_COUNT_BYTE 2
 #define TPM_CMD_ORDINAL_BYTE 6
 
-int tis_open(void)
-{
-	int rc;
-
-	if (chip.is_open) {
-		printk(BIOS_DEBUG, "%s() called twice.\n", __func__);
-		return -1;
-	}
-
-	rc = tpm_vendor_init(&chip, CONFIG_DRIVER_TPM_I2C_BUS,
-			     CONFIG_DRIVER_TPM_I2C_ADDR);
-	if (rc < 0)
-		chip.is_open = 0;
-
-	if (rc)
-		return -1;
-
-	return 0;
-}
-
-int tis_init(void)
-{
-	return tpm_vendor_probe(CONFIG_DRIVER_TPM_I2C_BUS,
-				CONFIG_DRIVER_TPM_I2C_ADDR);
-}
-
 static ssize_t tpm_transmit(const uint8_t *sbuf, size_t sbufsiz, void *rbuf,
 			size_t rbufsiz)
 {
@@ -107,7 +81,7 @@ out:
 	return rc;
 }
 
-int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
+static int i2c_tpm_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
 			    uint8_t *recvbuf, size_t *rbuf_len)
 {
 	ASSERT(sbuf_size >= 10);
@@ -144,3 +118,14 @@ int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
 
 	return 0;
 }
+
+tis_sendrecv_fn tis_probe(void)
+{
+	if (tpm_vendor_probe(CONFIG_DRIVER_TPM_I2C_BUS, CONFIG_DRIVER_TPM_I2C_ADDR))
+		return NULL;
+
+	if (tpm_vendor_init(&chip, CONFIG_DRIVER_TPM_I2C_BUS, CONFIG_DRIVER_TPM_I2C_ADDR))
+		return NULL;
+
+	return &i2c_tpm_sendrecv;
+}

src/drivers/i2c/tpm/tis_atmel.c

@@ -22,17 +22,7 @@ struct tpm_output_header {
 	uint32_t return_code;
 } __packed;
 
-int tis_open(void)
+static int i2c_tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
-{
-	return 0;
-}
-
-int tis_init(void)
-{
-	return 0;
-}
-
-int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
 			    uint8_t *recvbuf, size_t *rbuf_len)
 {
 	size_t hdr_bytes;
@@ -112,3 +102,8 @@ int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
 	/* Successful transfer */
 	return 0;
 }
+
+tis_sendrecv_fn tis_probe(void)
+{
+	return &i2c_tis_sendrecv;
+}

src/drivers/i2c/tpm/tpm.c

@@ -507,8 +507,6 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned int bus, uint32_t dev_addr)
 	tpm_dev.sleep_short = SLEEP_DURATION;
 	tpm_dev.sleep_long = SLEEP_DURATION_LONG;
 
-	chip->is_open = 1;
-
 	chip->req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID;
 	chip->req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID;
 	chip->req_canceled = TPM_STS_COMMAND_READY;

src/drivers/i2c/tpm/tpm.h

@@ -38,7 +38,6 @@ enum tpm_timeout {
 #define	TPM_DID_VID(l)			(0x0006 | ((l) << 4))
 
 struct tpm_chip {
-	int is_open;
 	uint8_t req_complete_mask;
 	uint8_t req_complete_val;
 	uint8_t req_canceled;

src/drivers/pc80/tpm/tis.c

@@ -373,7 +373,7 @@ static int tis_command_ready(u8 locality)
  * Returns 0 on success (the device is found or was found during an earlier
  * invocation) or TPM_DRIVER_ERR if the device is not found.
  */
-static u32 tis_probe(void)
+static u32 pc80_tis_probe(void)
 {
 	const char *device_name = "unknown";
 	const char *vendor_name = device_name;
@@ -608,26 +608,11 @@ static u32 tis_readresponse(u8 *buffer, size_t *len)
 }
 
 /*
- * tis_init()
- *
- * Initialize the TPM device. Returns 0 on success or TPM_DRIVER_ERR on
- * failure (in case device probing did not succeed).
- */
-int tis_init(void)
-{
-	if (tis_probe())
-		return TPM_DRIVER_ERR;
-	return 0;
-}
-
-/*
- * tis_open()
- *
  * Requests access to locality 0 for the caller.
  *
  * Returns 0 on success, TPM_DRIVER_ERR on failure.
  */
-int tis_open(void)
+static int pc80_tis_open(void)
 {
 	u8 locality = 0; /* we use locality zero for everything */
 
@@ -653,8 +638,6 @@ int tis_open(void)
 }
 
 /*
- * tis_sendrecv()
- *
  * Send the requested data to the TPM and then try to get its response
  *
  * @sendbuf - buffer of the data to send
@@ -665,7 +648,7 @@ int tis_open(void)
  * Returns 0 on success (and places the number of response bytes at recv_len)
  * or TPM_DRIVER_ERR on failure.
  */
-int tis_sendrecv(const uint8_t *sendbuf, size_t send_size,
+static int pc80_tpm_sendrecv(const uint8_t *sendbuf, size_t send_size,
 			     uint8_t *recvbuf, size_t *recv_len)
 {
 	if (tis_senddata(sendbuf, send_size)) {
@@ -677,6 +660,23 @@ int tis_sendrecv(const uint8_t *sendbuf, size_t send_size,
 	return tis_readresponse(recvbuf, recv_len);
 }
 
+/*
+ * tis_probe()
+ *
+ * Probe for the TPM device and set it up for use within locality 0. Returns
+ * pointer to send-receive function on success or NULL on failure.
+ */
+tis_sendrecv_fn tis_probe(void)
+{
+	if (pc80_tis_probe())
+		return NULL;
+
+	if (pc80_tis_open())
+		return NULL;
+
+	return &pc80_tpm_sendrecv;
+}
+
 /*
  * tis_setup_interrupt()
  *

src/drivers/spi/tpm/tis.c

@@ -5,8 +5,6 @@
 
 #include "tpm.h"
 
-static unsigned int tpm_is_open;
-
 static const struct {
 	uint16_t vid;
 	uint16_t did;
@@ -29,40 +27,7 @@ static const char *tis_get_dev_name(struct tpm2_info *info)
 	return "Unknown";
 }
 
-int tis_open(void)
+static int tpm_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
-{
-	if (tpm_is_open) {
-		printk(BIOS_ERR, "%s() called twice.\n", __func__);
-		return -1;
-	}
-	return 0;
-}
-
-int tis_init(void)
-{
-	struct spi_slave spi;
-	struct tpm2_info info;
-
-	if (spi_setup_slave(CONFIG_DRIVER_TPM_SPI_BUS,
-			    CONFIG_DRIVER_TPM_SPI_CHIP, &spi)) {
-		printk(BIOS_ERR, "Failed to setup TPM SPI slave\n");
-		return -1;
-	}
-
-	if (tpm2_init(&spi)) {
-		printk(BIOS_ERR, "Failed to initialize TPM SPI interface\n");
-		return -1;
-	}
-
-	tpm2_get_info(&info);
-
-	printk(BIOS_INFO, "Initialized TPM device %s revision %d\n",
-	       tis_get_dev_name(&info), info.revision);
-
-	return 0;
-}
-
-int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
 			uint8_t *recvbuf, size_t *rbuf_len)
 {
 	int len = tpm2_process_command(sendbuf, sbuf_size, recvbuf, *rbuf_len);
@@ -74,3 +39,27 @@ int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
 
 	return 0;
 }
+
+tis_sendrecv_fn tis_probe(void)
+{
+	struct spi_slave spi;
+	struct tpm2_info info;
+
+	if (spi_setup_slave(CONFIG_DRIVER_TPM_SPI_BUS,
+			    CONFIG_DRIVER_TPM_SPI_CHIP, &spi)) {
+		printk(BIOS_ERR, "Failed to setup TPM SPI slave\n");
+		return NULL;
+	}
+
+	if (tpm2_init(&spi)) {
+		printk(BIOS_ERR, "Failed to initialize TPM SPI interface\n");
+		return NULL;
+	}
+
+	tpm2_get_info(&info);
+
+	printk(BIOS_INFO, "Initialized TPM device %s revision %d\n",
+	       tis_get_dev_name(&info), info.revision);
+
+	return &tpm_sendrecv;
+}

src/security/tpm/tis.h

@@ -34,25 +34,6 @@ enum tis_status {
 };
 
 /*
- * tis_init()
- *
- * Initialize the TPM device. Returns 0 on success or -1 on
- * failure (in case device probing did not succeed).
- */
-int tis_init(void);
-
-/*
- * tis_open()
- *
- * Requests access to locality 0 for the caller.
- *
- * Returns 0 on success, -1 on failure.
- */
-int tis_open(void);
-
-/*
- * tis_sendrecv()
- *
  * Send the requested data to the TPM and then try to get its response
  *
  * @sendbuf - buffer of the data to send
@@ -63,9 +44,20 @@ int tis_open(void);
  * Returns 0 on success (and places the number of response bytes at recv_len)
  * or -1 on failure.
  */
-int tis_sendrecv(const u8 *sendbuf, size_t send_size, u8 *recvbuf,
+typedef int (*tis_sendrecv_fn)(const u8 *sendbuf, size_t send_size, u8 *recvbuf,
 			       size_t *recv_len);
 
+/*
+ * tis_probe()
+ *
+ * Probe for the TPM device and set it up for use within locality 0. Returns
+ * pointer to send-receive function on success or NULL on failure.
+ *
+ * Do not call this explicitly, it's meant to be used exclusively by TSS
+ * implementation (tlcl_lib_init() function to be specific).
+ */
+tis_sendrecv_fn tis_probe(void);
+
 /* TODO: This is supposed to be used only for Google TPM.
    Consider moving this to drivers/tpm/cr50.h. */
 /*

src/security/tpm/tss/tcg-1.2/tss.c

@@ -24,12 +24,18 @@
 #include <console/console.h>
 #define VBDEBUG(format, args...) printk(BIOS_DEBUG, format, ## args)
 
+static tis_sendrecv_fn tis_sendrecv;
+
 static int tpm_send_receive(const uint8_t *request,
 				uint32_t request_length,
 				uint8_t *response,
 				uint32_t *response_length)
 {
 	size_t len = *response_length;
+
+	if (tis_sendrecv == NULL)
+		die("TSS 1.2 wasn't initialized\n");
+
 	if (tis_sendrecv(request, request_length, response, &len))
 		return VB2_ERROR_UNKNOWN;
 	/* check 64->32bit overflow and (re)check response buffer overflow */
@@ -140,19 +146,14 @@ static uint32_t send(const uint8_t *command)
 
 /* Exported functions. */
 
-static uint8_t tlcl_init_done;
-
 uint32_t tlcl_lib_init(void)
 {
-	if (tlcl_init_done)
+	if (tis_sendrecv != NULL)
 		return VB2_SUCCESS;
 
-	if (tis_init())
+	tis_sendrecv = tis_probe();
+	if (tis_sendrecv == NULL)
 		return VB2_ERROR_UNKNOWN;
-	if (tis_open())
-		return VB2_ERROR_UNKNOWN;
-
-	tlcl_init_done = 1;
 
 	return VB2_SUCCESS;
 }

src/security/tpm/tss/tcg-2.0/tss.c

@@ -16,6 +16,8 @@
  * TPM2 specification.
  */
 
+static tis_sendrecv_fn tis_sendrecv;
+
 void *tpm_process_command(TPM_CC command, void *command_body)
 {
 	struct obuf ob;
@@ -26,6 +28,9 @@ void *tpm_process_command(TPM_CC command, void *command_body)
 	/* Command/response buffer. */
 	static uint8_t cr_buffer[TPM_BUFFER_SIZE];
 
+	if (tis_sendrecv == NULL)
+		die("TSS 2.0 wasn't initialized\n");
+
 	obuf_init(&ob, cr_buffer, sizeof(cr_buffer));
 
 	if (tpm_marshal_command(command, command_body, &ob) < 0) {
@@ -201,26 +206,18 @@ uint32_t tlcl_clear_control(bool disable)
 	return TPM_SUCCESS;
 }
 
-static uint8_t tlcl_init_done;
-
 /* This function is called directly by vboot, uses vboot return types. */
 uint32_t tlcl_lib_init(void)
 {
-	if (tlcl_init_done)
+	if (tis_sendrecv != NULL)
 		return VB2_SUCCESS;
 
-	if (tis_init()) {
+	tis_sendrecv = tis_probe();
-		printk(BIOS_ERR, "%s: tis_init returned error\n", __func__);
+	if (tis_sendrecv == NULL) {
+		printk(BIOS_ERR, "%s: tis_probe returned error\n", __func__);
 		return VB2_ERROR_UNKNOWN;
 	}
 
-	if (tis_open()) {
-		printk(BIOS_ERR, "%s: tis_open returned error\n", __func__);
-		return VB2_ERROR_UNKNOWN;
-	}
-
-	tlcl_init_done = 1;
-
 	return VB2_SUCCESS;
 }