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Diffstat (limited to 'doc/driver-model/UDM-tpm.txt')
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diff --git a/doc/driver-model/UDM-tpm.txt b/doc/driver-model/UDM-tpm.txt deleted file mode 100644 index 0beff4a..0000000 --- a/doc/driver-model/UDM-tpm.txt +++ /dev/null @@ -1,48 +0,0 @@ -The U-Boot Driver Model Project -=============================== -TPM system analysis -=================== -Marek Vasut <marek.vasut@gmail.com> -2012-02-23 - -I) Overview ------------ - -There is currently only one TPM chip driver available and therefore the API -controlling it is very much based on this. The API is very simple: - - int tis_open(void); - int tis_close(void); - int tis_sendrecv(const u8 *sendbuf, size_t send_size, - u8 *recvbuf, size_t *recv_len); - -The command operating the TPM chip only provides operations to send and receive -bytes from the chip. - -II) Approach ------------- - -The API can't be generalised too much considering there's only one TPM chip -supported. But it's a good idea to split the tis_sendrecv() function in two -functions. Therefore the new API will use register the TPM chip by calling: - - tpm_device_register(struct instance *i, const struct tpm_ops *ops); - -And the struct tpm_ops will contain the following members: - - struct tpm_ops { - int (*tpm_open)(struct instance *i); - int (*tpm_close)(struct instance *i); - int (*tpm_send)(const uint8_t *buf, const size_t size); - int (*tpm_recv)(uint8_t *buf, size_t *size); - }; - -The behaviour of "tpm_open()" and "tpm_close()" will basically copy the -behaviour of "tis_open()" and "tis_close()". The "tpm_send()" will be based on -the "tis_senddata()" and "tis_recv()" will be based on "tis_readresponse()". - -III) Analysis of in-tree drivers --------------------------------- - -There is only one in-tree driver present, the "drivers/tpm/generic_lpc_tpm.c", -which will be simply converted as outlined in previous chapter. |