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Wed, 16 Sep 2026 09:27:46 -0700 (PDT) From: Orgad Shaneh To: miquel.raynal@bootlin.com Cc: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, richard@nod.at, vigneshr@ti.com Subject: Re: [PATCH v2] mtd: cfi_cmdset_0002: cap the write-buffer chunk at 256 bytes on an x8 device Date: Wed, 16 Sep 2026 16:27:45 +0000 Message-ID: <20260916162746.308008-1-orgads@gmail.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <8733v9mdro.fsf@bootlin.com> References: <8733v9mdro.fsf@bootlin.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Miquel, Thanks for the review. v3 sent as a reply to v2. > This sentence does not mean anything, I'm sorry. Rewritten: the count goes out as a single bus word, CMD() replicates it into every device lane, and an x8 part reads it off eight data lines, so anything above 255 is truncated there. > failed? do you have hardware that actually triggered that issue? Yes - a Cavium Octeon CN6335 board whose NOR is an M29EW strapped to x8. The log in the commit message is from it, and the clamp fixes it. v3 names the board. > That's incorrect. It indicates until when we need to backport it. Added. I checked the code is really there: 1da177e4c3f4 already sends CMD(words - 1) and already takes the chunk size from MaxBufWriteSize. Vignesh is on To: for v3. Thanks, Orgad