drivers/pc80/tpm: probe for TPM family of a device

At the moment this is to handle the situation when device ID is the
same for TPM1 and TPM2 versions of a device.  Later this TPM family will
be returned to the caller.

Change-Id: I23b85e6da0e02999704f3ec30412db0bdce2dd8a
Ticket: https://ticket.coreboot.org/issues/433
Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/76955
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

1 files changed, 79 insertions, 25 deletions

diff --git a/src/drivers/pc80/tpm/tis.c b/src/drivers/pc80/tpm/tis.c
index 2099bb7bf699..90fa32e31808 100644
--- a/src/drivers/pc80/tpm/tis.c
+++ b/src/drivers/pc80/tpm/tis.c
@@ -55,6 +55,7 @@
 #define TIS_REG_STS                    0x18
 #define TIS_REG_BURST_COUNT            0x19
 #define TIS_REG_DATA_FIFO              0x24
+#define TIS_REG_INTF_ID                0x30
 #define TIS_REG_DID_VID                0xf00
 #define TIS_REG_RID                    0xf04
 
@@ -77,13 +78,19 @@
  /* 1 second is plenty for anything TPM does.*/
 #define MAX_DELAY_US	USECS_PER_SEC
 
+enum tpm_family {
+	TPM_UNKNOWN = 0,
+	TPM_1 = 1,
+	TPM_2 = 2,
+};
+
 /*
  * Structures defined below allow creating descriptions of TPM vendor/device
- * ID information for run time discovery. The only device the system knows
- * about at this time is Infineon slb9635
+ * ID information for run time discovery.
  */
 struct device_name {
 	u16 dev_id;
+	enum tpm_family family;
 	const char *const dev_name;
 };
 
@@ -94,37 +101,33 @@ struct vendor_name {
 };
 
 static const struct device_name atmel_devices[] = {
-	{0x3204, "AT97SC3204"},
+	{0x3204, TPM_1, "AT97SC3204"},
 	{0xffff}
 };
 
 static const struct device_name infineon_devices[] = {
-	{0x000b, "SLB9635 TT 1.2"},
-#if CONFIG(TPM2)
-	{0x001a, "SLB9665 TT 2.0"},
-	{0x001b, "SLB9670 TT 2.0"},
-	{0x001d, "SLB9672 TT 2.0"},
-#else
-	{0x001a, "SLB9660 TT 1.2"},
-	{0x001b, "SLB9670 TT 1.2"},
-#endif
+	{0x000b, TPM_1, "SLB9635 TT 1.2"},
+	{0x001a, TPM_1, "SLB9660 TT 1.2"},
+	{0x001b, TPM_1, "SLB9670 TT 1.2"},
+	{0x001a, TPM_2, "SLB9665 TT 2.0"},
+	{0x001b, TPM_2, "SLB9670 TT 2.0"},
+	{0x001d, TPM_2, "SLB9672 TT 2.0"},
 	{0xffff}
 };
 
 static const struct device_name nuvoton_devices[] = {
-	{0x00fe, "NPCT420AA V2"},
+	{0x00fe, TPM_1, "NPCT420AA V2"},
 	{0xffff}
 };
 
 static const struct device_name stmicro_devices[] = {
-	{0x0000, "ST33ZP24" },
+	{0x0000, TPM_1, "ST33ZP24" },
 	{0xffff}
 };
 
 static const struct device_name swtpm_devices[] = {
-#if CONFIG(TPM2)
-	{0x0001, "SwTPM 2.0" },
-#endif
+	{0x0001, TPM_1, "SwTPM 1.2" },
+	{0x0001, TPM_2, "SwTPM 2.0" },
 	{0xffff}
 };
 
@@ -190,6 +193,20 @@ static inline void tpm_write_access(u8 data, int locality)
 	write8(TIS_REG(locality, TIS_REG_ACCESS), data);
 }
 
+static inline u32 tpm_read_intf_cap(int locality)
+{
+	u32 value = read32(TIS_REG(locality, TIS_REG_INTF_CAPABILITY));
+	TPM_DEBUG_IO_READ(TIS_REG_INTF_CAPABILITY, value);
+	return value;
+}
+
+static inline u32 tpm_read_intf_id(int locality)
+{
+	u32 value = read32(TIS_REG(locality, TIS_REG_INTF_ID));
+	TPM_DEBUG_IO_READ(TIS_REG_INTF_ID, value);
+	return value;
+}
+
 static inline u32 tpm_read_did_vid(int locality)
 {
 	u32 value = read32(TIS_REG(locality, TIS_REG_DID_VID));
@@ -365,12 +382,15 @@ static tpm_result_t tis_command_ready(u8 locality)
  */
 static tpm_result_t pc80_tis_probe(void)
 {
-	const char *device_name = "unknown";
-	const char *vendor_name = device_name;
+	const char *device_name = NULL;
+	const char *vendor_name = NULL;
 	const struct device_name *dev;
-	u32 didvid;
+	u32 didvid, intf_id;
 	u16 vid, did;
+	u8 locality = 0, intf_type;
 	int i;
+	enum tpm_family family;
+	const char *family_str;
 
 	if (vendor_dev_id)
 		return TPM_SUCCESS;  /* Already probed. */
@@ -381,21 +401,45 @@ static tpm_result_t pc80_tis_probe(void)
 		return TPM_CB_FAIL;
 	}
 
+	intf_id = tpm_read_intf_id(locality);
+	intf_type = (intf_id & 0xf);
+	if (intf_type == 0xf) {
+		u32 intf_cap = tpm_read_intf_cap(locality);
+		u8 intf_version = (intf_cap >> 28) & 0x7;
+		switch (intf_version) {
+		case 0:
+		case 2:
+			family = TPM_1;
+			break;
+		case 3:
+			family = TPM_2;
+			break;
+		default:
+			printf("%s: Unexpected TPM interface version: %d\n", __func__,
+			       intf_version);
+			return TPM_CB_PROBE_FAILURE;
+		}
+	} else if (intf_type == 0) {
+		family = TPM_2;
+	} else {
+		printf("%s: Unexpected TPM interface type: %d\n", __func__, intf_type);
+		return TPM_CB_PROBE_FAILURE;
+	}
+
 	vendor_dev_id = didvid;
 
 	vid = didvid & 0xffff;
 	did = (didvid >> 16) & 0xffff;
 	for (i = 0; i < ARRAY_SIZE(vendor_names); i++) {
 		int j = 0;
-		u16 known_did;
 		if (vid == vendor_names[i].vendor_id) {
 			vendor_name = vendor_names[i].vendor_name;
 		} else {
 			continue;
 		}
 		dev = &vendor_names[i].dev_names[j];
-		while ((known_did = dev->dev_id) != 0xffff) {
-			if (known_did == did) {
+		while (dev->dev_id != 0xffff) {
+			if (dev->dev_id == did && dev->family == family) {
 				device_name = dev->dev_name;
 				break;
 			}
@@ -404,8 +448,18 @@ static tpm_result_t pc80_tis_probe(void)
 		}
 		break;
 	}
-	/* this will have to be converted into debug printout */
-	printk(BIOS_INFO, "Found TPM %s by %s\n", device_name, vendor_name);
+
+	family_str = (family == TPM_1 ? "TPM 1.2" : "TPM 2.0");
+	if (vendor_name == NULL) {
+		printk(BIOS_INFO, "Found %s 0x%04x by 0x%04x\n", family_str, did, vid);
+	} else if (device_name == NULL) {
+		printk(BIOS_INFO, "Found %s 0x%04x by %s (0x%04x)\n", family_str, did,
+		       vendor_name, vid);
+	} else {
+		printk(BIOS_INFO, "Found %s %s (0x%04x) by %s (0x%04x)\n", family_str,
+		       device_name, did, vendor_name, vid);
+	}
+
 	return TPM_SUCCESS;
 }