From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E991C433DF for ; Wed, 20 May 2020 12:21:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5033720756 for ; Wed, 20 May 2020 12:21:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726799AbgETMVa (ORCPT ); Wed, 20 May 2020 08:21:30 -0400 Received: from mail.baikalelectronics.com ([87.245.175.226]:58416 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726224AbgETMVa (ORCPT ); Wed, 20 May 2020 08:21:30 -0400 Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id 7033F8030875; Wed, 20 May 2020 12:21:27 +0000 (UTC) X-Virus-Scanned: amavisd-new at baikalelectronics.ru Received: from mail.baikalelectronics.ru ([127.0.0.1]) by localhost (mail.baikalelectronics.ru [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HpXx65hG0gh0; Wed, 20 May 2020 15:21:26 +0300 (MSK) Date: Wed, 20 May 2020 15:21:25 +0300 From: Serge Semin To: Thomas Bogendoerfer CC: Serge Semin , Alexey Malahov , Paul Burton , Ralf Baechle , Greg Kroah-Hartman , Arnd Bergmann , Rob Herring , , , Vincenzo Frascino , Thomas Gleixner , , Subject: Re: [PATCH v2 18/20] mips: csrc-r4k: Decrease r4k-clocksource rating if CPU_FREQ enabled Message-ID: <20200520122125.opn53q5wxvcc4ath@mobilestation> References: <20200506174238.15385-19-Sergey.Semin@baikalelectronics.ru> <20200508154150.GB22247@alpha.franken.de> <20200511133121.cz5axbwynhmqkx7x@mobilestation> <20200515074827.6p5zx4sb3bmavjih@mobilestation> <20200515210647.GA22922@alpha.franken.de> <20200518134820.wedoumgbsllvhem6@mobilestation> <20200518163206.GA17800@alpha.franken.de> <20200518205752.txbylbjt2zkwdwwe@mobilestation> <20200519155053.GB15797@alpha.franken.de> <20200520121201.wohv6u646rx5otkf@mobilestation> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200520121201.wohv6u646rx5otkf@mobilestation> X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Wed, May 20, 2020 at 03:12:02PM +0300, Serge Semin wrote: > On Tue, May 19, 2020 at 05:50:53PM +0200, Thomas Bogendoerfer wrote: > > On Mon, May 18, 2020 at 11:57:52PM +0300, Serge Semin wrote: > > > On Mon, May 18, 2020 at 06:32:06PM +0200, Thomas Bogendoerfer wrote: > > > > On Mon, May 18, 2020 at 04:48:20PM +0300, Serge Semin wrote: [nip] > > > > > ├─>[PATCH v2 13/20] mips: early_printk_8250: Use offset-sized IO-mem accessors > > > > > > > > that's broken. A reg shift of 2 doesn't mean we could use 32bit access > > > > to the registers on other platforms. As I don't think adding some ifdefery > > > > makes things nicer, just implement the your prom_putchar in board code. > > > > > > I thought about that initially, but then I decided to alter the generic > > > early_printk_8250 code instead. My version of prom_putchar() would be almost > > > the same as one implemented in the early_printk_8250 module except minor > > > modification of replacing readb/writeb methods with readl/writel. So I didn't > > > want to duplicate the code, but wanted to provide a general way to fix the > > > problem potentially also for another platforms. > > > > > > Since you don't like this fix alternatively I'd suggest to add the reg_width > > > parameter passed to the setup_8250_early_printk_port() method like this: > > > -setup_8250_early_printk_port(unsigned long base, unsigned int reg_shift, > > > - unsigned int timeout) > > > +setup_8250_early_printk_port(unsigned long base, unsigned int reg_shift, > > > + unsigned int reg_width, unsigned int timeout) > > > > > > By reg_width parameter we could determine the actual width of the register: > > > static inline u8 serial_in(int offset) > > > { > > > - return readb(serial8250_base + (offset << serial8250_reg_shift)); > > > + u8 ret = 0xFF; > > > + > > > + offset <<= serial8250_reg_shift; > > > + switch (serial8250_reg_width) { > > > + case 1: > > > + ret = readb(serial8250_base + offset); > > > + break; > > > + case 2: > > > + ret = readw(serial8250_base + offset); > > > + break; > > > + case 4: > > > + ret = readl(serial8250_base + offset); > > > + break; > > > + default: > > > + break; > > > + } > > > + > > > + return ret; > > > } > > > > > > The similar modification will be implemented for serial_out(). I'll also modify > > > > look at the lines of code you are adding. Doing your own prom_putchar will > > probably have less lines. > > > > > What do you think about this? > > > > please do your own prom_putchar. > > One more time regarding this problem but in appliance to another part of the > MIPS code. I've missed the patch to draw your attention to: > [PATCH v2 14/20] mips: Use offset-sized IO-mem accessors in CPS debug printout > > There I've applied the same fix as in the patch: > [PATCH v2 13/20] mips: early_printk_8250: Use offset-sized IO-mem accessors > > Since you don't like the way I initially fixed it, suppose there we don't have > another way but to introduce something like CONFIG_MIPS_CPS_NS16550_WIDTH > parameter to select a proper accessors, like sw in our case, and sb by defaul). > Right? > > (Note UART_L is incorrectly created in that patch, I'll remove that macro in > v3.) Hm, actually no. The macro is correct. According to the code _mips_cps_putc() always perform lw from the UART MMIO registers. This must be a bug. Don't you think? -Sergey > > -Sergey >