From mboxrd@z Thu Jan 1 00:00:00 1970 From: Angelo Dureghello Subject: Re: coldfire uart question Date: Tue, 17 Oct 2017 23:07:25 +0200 Message-ID: <9fba01f2-9bf4-ecc2-b32e-2e75e203e189@sysam.it> References: <1f18ad0d-d147-5c64-ad65-a4bc545d4bff@sysam.it> <077ccbca-027c-67fe-602e-7105d5c46edf@westnet.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: Received: from sysam.it ([5.39.81.93]:50517 "EHLO sysam.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764337AbdJQVH2 (ORCPT ); Tue, 17 Oct 2017 17:07:28 -0400 In-Reply-To: <077ccbca-027c-67fe-602e-7105d5c46edf@westnet.com.au> Content-Language: en-US Sender: linux-m68k-owner@vger.kernel.org List-Id: linux-m68k@vger.kernel.org To: Greg Ungerer , Linux/m68k Cc: Finn Thain Hi Greg and all, On 16/10/2017 01:57, Greg Ungerer wrote: > Hi Angelo, > > On 16/10/17 03:28, Angelo Dureghello wrote: >> i was trying a file transfer with xmodem-1k >> and uClinux "rx" on the mcf54415 stnmark2 board side. >> >> This using a recent mainline kernel: >> / # cat /proc/version >> uClinux version 4.14.0-rc4stmark2-001-00118-g811fdbb62a9d >> / # >> >> So, as per xmodem-1k, i send 3 bytes header, >> a 1024 bytes block, and 2 bytes crc16. But "rx" timeouts >> waiting the block. >> >> Adding some traces to "rx", it timeouts since some bytes >> (5 to 10) randomly positioned in the block are not received. >> Of course they have been sent (scope checked). > > Check if you are getting overruns on the port: > > cat /proc/tty/driver/mcf thanks, yes, you are right / # cat /proc/tty/driver/mcf serinfo:1.0 driver revision: 0: uart:ColdFire UART mmio:0xFC060000 irq:90 tx:4047 rx:1057 oe:8 RTS|DTR|CD 1: uart:ColdFire UART mmio:0xFC064000 irq:91 tx:0 rx:0 CD 2: uart:ColdFire UART mmio:0xFC068000 irq:92 tx:0 rx:0 CD 3: uart:ColdFire UART mmio:0xFC06C000 irq:93 tx:0 rx:0 CD / # I am at 115200,n,8,1 now. I checked the u-boot driver and there is no interrupt handler, only a coldfire_serial_getc checking USR_RXRDY. Could the RxFIFO_Full interrupt flag be of any help ? > > Regards > Greg > > Regards, Angelo > >> The same 1024 bytes transfer in u-boot (y-modem) >> always succeed. >> >> Since mcf54415 has a 4 slots RX fifo UART, i was wondering >> if the mcf.c uart driver is not fast enough to read the data, >> or, where the "linux" limitation could be. >> >> Regards, >> Angelo Dureghello >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-m68k" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at  http://vger.kernel.org/majordomo-info.html >> >