DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-20 are pending.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1, 11, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Das Sharma et al (US20220342840) as applied to claim0 above, and further in view of Nicol (US10374981).
As to claim 1, Das Sharma discloses a method of die-to-die (D2D) credit-based flow control (Fig. 2 with D2D link coupling processor core and external device that is managed via a credit system, para. 0034), the method comprising: a first packet to be transmitted from a-the source to a destination based on a credit count (Fig. 2 with processing core coupled to external device which is the destination, para. 0034) ;
the credit count based on transmitting a flit of the first packet to the destination (Fig. 2 via the stack, para. 0034); and the credit count based on receiving a first return credit from the destination (Fig. 1, where the response from the destination restores the credit limits, para. 0034).
Das Sharma does not disclose explicitly that the source is the managing agent in the process.
Nicol teaches in Fig. 6, where the source, 640 comprises counter 642 that increments the decrements the sending path, and increments based on credit accumulation unit 618 . COL. 9, lines 25 – 67. One of ordinary skill in the art before the effective filing date of the claimed invention to allow the data flow of a broad spectrum of frequencies, and types without any downsides, COL. 2, lines 10 – 20).
As to claim 20, Das Sharma discloses a non-transitory computer-readable medium storing code that comprises instructions executable by a processor (Fig. 2 with D2D link coupling processor core and external device that is managed via a credit system, para. 0034), of a die-to-die (D2D) : a first packet to be transmitted from a-the source to a destination based on a credit count (Fig. 2 with processing core coupled to external device which is the destination, para. 0034) ;
the credit count based on transmitting a flit of the first packet to the destination (Fig. 2 via the stack, para. 0034); and the credit count based on receiving a first return credit from the destination (Fig. 1, where the response from the destination restores the credit limits, para. 0034).
Nicol teaches in Fig. 6, where the source, 640 comprises counter 642 that increments the decrements the sending path, and increments based on credit accumulation unit 618 . COL. 9, lines 25 – 67. One of ordinary skill in the art before the effective filing date of the claimed invention to allow the data flow of a broad spectrum of frequencies, and types without any downsides, COL. 2, lines 10 – 20).
As to claim 11, Das Sharma discloses the method, pausing transmission for at least one clock cycle based on a determination that the credit count is zero (Fig. 13, where the credit count is zero, and counters needed refreshing, para. 0080).
Claim(s) 6 – 10, 12-15 are rejected under 35 U.S.C. 103 as being unpatentable over Das Sharma/Nicol and further in view of Agarwal et al (US20240281399) hereinafter Agarwal.
As to claim 6, Das Sharma/Nicol does not disclose the method, wherein the first return credit is received in a header flit of a second packet that the source receives from the destination.
Agarwal teaches in Fig. 5, wherein the first return credit is received in a header flit of a second packet that the source receives from the destination (Fig. 5, and para. 0085, where the response is registered). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 7, Agarwal discloses the method, wherein the first return credit is piggybacked on the second packet based on the second packet including at least one payload flit (Fig. 1, and para. 0030). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 8, Agarwal discloses the method, wherein the second packet is received as a standalone message from the destination based on the second packet being configured without payload flits. (Target 112 sends message without flits, para. 0084). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 9, Agarwal discloses the method, wherein transmission of return credits is synchronized to a clock cycle (CXL transactions implicitly use a clock cycle, para. 0086). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 10, Agarwal discloses the method, wherein allowing the packet to be transmitted from the source to the destination is based on the credit count being non-zero (Fig. 5, and step 504 illustrates said, para. 0088). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 12, Agarwal discloses the method, wherein the credit count is maintained on a protocol layer of a die-to-die interconnect of the source (Fig. 1, and hub 115 comprising the count, para. 0034). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 13, Agarwal discloses the method, wherein the first packet includes a header flit, one or more payload flits, and a tail flit (Fig. 4B and example 4 illustrating flit make up, para. 0004). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 14, Agarwal discloses the method, wherein the source comprises a first D2D physical layer (PHY) that is communicatively linked to a second D2D PHY of the destination (Fig. 1, where PHY illustrates the coupling, para. 0033). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
As to claim 15, Agarwal discloses the method, wherein the source comprises a compute die and the destination comprises a buffer die (Fig. 1, with host 108, and slave 112, para. 0024). One of ordinary skill in the art before the effective filing date of the claimed invention would use the packing system of Agarwal in the system of Das Sharma/Nicol to add efficiency in the data flow (para. 0002).
Allowable Subject Matter
Claims 2- 5 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claims 16 – 19 are allowed.
The following is an examiner’s statement of reasons for allowance: Independent claim 16 and its dependents thereof are allowed because the prior art either alone or in combination fail to anticipate or render obvious, the claimed limitation of
“incrementing, at the destination, a credit count based on receiving the first return credit from the source; allowing, at the destination, a second packet to be transmitted to the source based on the credit count; and decrementing, at the destination, the credit count based on transmitting a flit of the second packet to the source.”
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Response to Arguments
Applicant’s arguments with respect to claim(s) 1-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRISTOPHER ANTHONY DALEY whose telephone number is (571)272-3625. The examiner can normally be reached 7 - 3:30 pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Dr. Henry Tsai can be reached at 571 2724176. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/C.A.D/Examiner, Art Unit 2184
/HENRY TSAI/Supervisory Patent Examiner, Art Unit 2184