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Jan 2022 12:06:37.9886 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: fd4b1729-b18d-46d2-9ba0-2717b852b252 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: f7S0i1brhG/zORkxB4KdrDiJDBU0+VA4sDmbmceMG9lrHF9DJspEvDz8jPqN9P6KuvUeG4lyWtSDA/FtC1uZziP08uwJEveS4NlrlD8O9kQ= X-MS-Exchange-Transport-CrossTenantHeadersStamped: LO2P123MB5280 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUK97A341 smtp.mailfrom=tomasz.mon@camlingroup.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: camlingroup.com Content-Type: text/plain; charset=UTF-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On 14.01.2022 08:44, Tomasz Mo=C5=84 wrote: > Aging timer resets with every received character. Worst case scenario > happens when RX data intercharacter delay is slightly less than the > aging timer timeout (8 characters time). The upper bound of the time > a character can wait in RxFIFO before being read is: > (RXTL - 1) * (8 character time timeout + received 1 character time) s/being read/interrupt is raised/ This description is not precise. The character can wait in RxFIFO longer than the mentioned upper bound, as the time it takes to actually read it from RxFIFO is the sum of how long it takes to raise the interrupt and actual interrupt handling time. Best Regards, Tomasz Mon