tpm: allow TPM v1 and v2 to be compiled at the same time

While there is probably no reason to do so in a real life situation, it
will allow to compile test both stacks with the same sandbox defconfig.

As we cannot define two 'tpm' commands at the same time, the command for
TPM v1 is still called 'tpm' and the one for TPM v2 'tpm2'. While this
is the exact command name that must be written into eg. test files, any
user already using the TPM v2 stack can continue to do so by just writing
'tpm' because as long as TPM v1 support is not compiled, U-Boot prompt
will search for the closest command named after 'tpm'.

The command set can also be changed at runtime (not supported yet, but
ready to be), but as one can compile only either one stack or the other,
there is still one spot in the code where conditionals are used: to
retrieve the v1 or v2 command set.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
[trini: In sandbox_tpm2_fill_buf() use NULL not \0 to ensure NULL
terminated string due to LLVM warning]
Signed-off-by: Tom Rini <trini@konsulko.com>

cmd/tpm-common.c

@@ -273,12 +273,34 @@ int do_tpm_init(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 int do_tpm(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	cmd_tbl_t *tpm_commands, *cmd;
+	struct tpm_chip_priv *priv;
+	struct udevice *dev;
 	unsigned int size;
+	int ret;
 
 	if (argc < 2)
 		return CMD_RET_USAGE;
 
-	tpm_commands = get_tpm_commands(&size);
+	ret = get_tpm(&dev);
+	if (ret)
+		return ret;
+
+	priv = dev_get_uclass_priv(dev);
+
+	/* Below getters return NULL if the desired stack is not built */
+	switch (priv->version) {
+	case TPM_V1:
+		tpm_commands = get_tpm1_commands(&size);
+		break;
+	case TPM_V2:
+		tpm_commands = get_tpm2_commands(&size);
+		break;
+	default:
+		tpm_commands = NULL;
+	}
+
+	if (!tpm_commands)
+		return CMD_RET_USAGE;
 
 	cmd = find_cmd_tbl(argv[1], tpm_commands, size);
 	if (!cmd)

cmd/tpm-v1.c

@@ -608,7 +608,7 @@ static cmd_tbl_t tpm1_commands[] = {
 #endif /* CONFIG_TPM_LIST_RESOURCES */
 };
 
-cmd_tbl_t *get_tpm_commands(unsigned int *size)
+cmd_tbl_t *get_tpm1_commands(unsigned int *size)
 {
 	*size = ARRAY_SIZE(tpm1_commands);
 

cmd/tpm-v2.c

@@ -319,14 +319,14 @@ static cmd_tbl_t tpm2_commands[] = {
 			 do_tpm_pcr_setauthvalue, "", ""),
 };
 
-cmd_tbl_t *get_tpm_commands(unsigned int *size)
+cmd_tbl_t *get_tpm2_commands(unsigned int *size)
 {
 	*size = ARRAY_SIZE(tpm2_commands);
 
 	return tpm2_commands;
 }
 
-U_BOOT_CMD(tpm, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command",
+U_BOOT_CMD(tpm2, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command",
 "<command> [<arguments>]\n"
 "\n"
 "info\n"

drivers/tpm/Kconfig

@@ -4,9 +4,6 @@
 
 menu "TPM support"
 
-comment "Please select only one TPM revision"
-	depends on TPM_V1 && TPM_V2
-
 config TPM_V1
 	bool "TPMv1.x support"
 	depends on TPM
@@ -15,7 +12,7 @@ config TPM_V1
 	  Major TPM versions are not compatible at all, choose either
 	  one or the other. This option enables TPMv1.x drivers/commands.
 
-if TPM_V1 && !TPM_V2
+if TPM_V1
 
 config TPM_TIS_SANDBOX
 	bool "Enable sandbox TPM driver"
@@ -127,7 +124,7 @@ config TPM_V2
 	  Major TPM versions are not compatible at all, choose either
 	  one or the other. This option enables TPMv2.x drivers/commands.
 
-if TPM_V2 && !TPM_V1
+if TPM_V2
 
 config TPM2_TIS_SANDBOX
 	bool "Enable sandbox TPMv2.x driver"

drivers/tpm/tpm-uclass.c

@@ -7,11 +7,8 @@
 #include <common.h>
 #include <dm.h>
 #include <linux/unaligned/be_byteshift.h>
-#if defined(CONFIG_TPM_V1)
 #include <tpm-v1.h>
-#elif defined(CONFIG_TPM_V2)
 #include <tpm-v2.h>
-#endif
 #include "tpm_internal.h"
 
 int tpm_open(struct udevice *dev)

drivers/tpm/tpm2_tis_sandbox.c

@@ -232,7 +232,7 @@ static int sandbox_tpm2_fill_buf(u8 **recv, size_t *recv_len, u16 tag, u32 rc)
 	*recv += sizeof(rc);
 
 	/* Add trailing \0 */
-	*recv = '\0';
+	*recv = NULL;
 
 	return 0;
 }
@@ -590,6 +590,9 @@ static int sandbox_tpm2_probe(struct udevice *dev)
 	struct sandbox_tpm2 *tpm = dev_get_priv(dev);
 	struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
 
+	/* Use the TPM v2 stack */
+	priv->version = TPM_V2;
+
 	memset(tpm, 0, sizeof(*tpm));
 
 	priv->pcr_count = 32;

drivers/tpm/tpm2_tis_spi.c

@@ -510,6 +510,7 @@ static int tpm_tis_spi_cleanup(struct udevice *dev)
 static int tpm_tis_spi_open(struct udevice *dev)
 {
 	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
 
 	if (chip->is_open)
 		return -EBUSY;
@@ -575,6 +576,9 @@ static int tpm_tis_spi_probe(struct udevice *dev)
 	struct tpm_chip *chip = dev_get_priv(dev);
 	int ret;
 
+	/* Use the TPM v2 stack */
+	priv->version = TPM_V2;
+
 	if (IS_ENABLED(CONFIG_DM_GPIO)) {
 		struct gpio_desc reset_gpio;
 

include/tpm-common.h

@@ -26,6 +26,16 @@ enum tpm_duration {
 /* Max buffer size supported by our tpm */
 #define TPM_DEV_BUFSIZE		1260
 
+/**
+ * enum tpm_version - The version of the TPM stack to be used
+ * @TPM_V1:		Use TPM v1.x stack
+ * @TPM_V2:		Use TPM v2.x stack
+ */
+enum tpm_version {
+	TPM_V1 = 0,
+	TPM_V2,
+};
+
 /**
  * struct tpm_chip_priv - Information about a TPM, stored by the uclass
  *
@@ -33,20 +43,23 @@ enum tpm_duration {
  * communcation is attempted. If the device has an xfer() method, this is
  * not needed. There is no need to set up @buf.
  *
+ * @version:		TPM stack to be used
  * @duration_ms:	Length of each duration type in milliseconds
  * @retry_time_ms:	Time to wait before retrying receive
+ * @buf:		Buffer used during the exchanges with the chip
  * @pcr_count:		Number of PCR per bank
  * @pcr_select_min:	Minimum size in bytes of the pcrSelect array
- * @buf:		Buffer used during the exchanges with the chip
  */
 struct tpm_chip_priv {
+	enum tpm_version version;
+
 	uint duration_ms[TPM_DURATION_COUNT];
 	uint retry_time_ms;
-#if defined(CONFIG_TPM_V2)
+	u8 buf[TPM_DEV_BUFSIZE + sizeof(u8)];  /* Max buffer size + addr */
+
+	/* TPM v2 specific data */
 	uint pcr_count;
 	uint pcr_select_min;
-#endif
-	u8 buf[TPM_DEV_BUFSIZE + sizeof(u8)];  /* Max buffer size + addr */
 };
 
 /**
@@ -208,10 +221,25 @@ int tpm_xfer(struct udevice *dev, const u8 *sendbuf, size_t send_size,
 int tpm_init(void);
 
 /**
- * Retrieve the array containing all the commands.
+ * Retrieve the array containing all the v1 (resp. v2) commands.
  *
  * @return a cmd_tbl_t array.
  */
-cmd_tbl_t *get_tpm_commands(unsigned int *size);
+#if defined(CONFIG_TPM_V1)
+cmd_tbl_t *get_tpm1_commands(unsigned int *size);
+#else
+static inline cmd_tbl_t *get_tpm1_commands(unsigned int *size)
+{
+	return NULL;
+}
+#endif
+#if defined(CONFIG_TPM_V2)
+cmd_tbl_t *get_tpm2_commands(unsigned int *size);
+#else
+static inline cmd_tbl_t *get_tpm2_commands(unsigned int *size)
+{
+	return NULL;
+}
+#endif
 
 #endif /* __TPM_COMMON_H */