From patchwork Mon Jun 8 09:59:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 214447 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 95C9FC433E1 for ; Mon, 8 Jun 2020 10:04:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7F612206C3 for ; Mon, 8 Jun 2020 10:04:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729286AbgFHKEr (ORCPT ); Mon, 8 Jun 2020 06:04:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729268AbgFHKEr (ORCPT ); Mon, 8 Jun 2020 06:04:47 -0400 Received: from laurent.telenet-ops.be (laurent.telenet-ops.be [IPv6:2a02:1800:110:4::f00:19]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52B7AC08C5C4 for ; Mon, 8 Jun 2020 03:04:47 -0700 (PDT) Received: from ramsan ([IPv6:2a02:1810:ac12:ed60:c85f:a5bf:b1bd:702b]) by laurent.telenet-ops.be with bizsmtp id oZzi2200P0R8aca01Zzis9; Mon, 08 Jun 2020 11:59:43 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan with esmtp (Exim 4.90_1) (envelope-from ) id 1jiEZC-0007P6-D9; Mon, 08 Jun 2020 11:59:42 +0200 Received: from geert by rox.of.borg with local (Exim 4.90_1) (envelope-from ) id 1jiEZC-0007xC-Be; Mon, 08 Jun 2020 11:59:42 +0200 From: Geert Uytterhoeven To: Mark Brown Cc: Chris Brandt , linux-spi@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-sh@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH 3/8] spi: rspi: Clean up Bit Rate Division Setting handling Date: Mon, 8 Jun 2020 11:59:35 +0200 Message-Id: <20200608095940.30516-4-geert+renesas@glider.be> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200608095940.30516-1-geert+renesas@glider.be> References: <20200608095940.30516-1-geert+renesas@glider.be> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Add a macro for configuring the Bit Rate Division Setting field in Command Registers, instead of open-coding the same operation using a hardcoded shift. Rename "div" to "brdv", as it is not a plain divider value, but controls a power-of-two divider. Signed-off-by: Geert Uytterhoeven --- drivers/spi/spi-rspi.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index 1b635d6b7881f5b9..450a42ec2141a895 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -161,6 +161,7 @@ #define SPCMD_SPRW 0x0010 /* SPI Read/Write Access (Dual/Quad) */ #define SPCMD_SSLA(i) ((i) << 4) /* SSL Assert Signal Setting */ #define SPCMD_BRDV_MASK 0x000c /* Bit Rate Division Setting */ +#define SPCMD_BRDV(brdv) ((brdv) << 2) #define SPCMD_CPOL 0x0002 /* Clock Polarity Setting */ #define SPCMD_CPHA 0x0001 /* Clock Phase Setting */ @@ -290,24 +291,24 @@ static int rspi_set_config_register(struct rspi_data *rspi, int access_size) static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size) { int spbr; - int div = 0; + int brdv = 0; unsigned long clksrc; /* Sets output mode, MOSI signal, and (optionally) loopback */ rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); clksrc = clk_get_rate(rspi->clk); - while (div < 3) { + while (brdv < 3) { if (rspi->speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */ break; - div++; + brdv++; clksrc /= 2; } /* Sets transfer bit rate */ spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1; rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); - rspi->spcmd |= div << 2; + rspi->spcmd |= SPCMD_BRDV(brdv); /* Disable dummy transmission, set byte access */ rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR); From patchwork Mon Jun 8 09:59:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 214446 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 CBA2DC433DF for ; Mon, 8 Jun 2020 10:04:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD142206C3 for ; Mon, 8 Jun 2020 10:04:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728745AbgFHKEt (ORCPT ); Mon, 8 Jun 2020 06:04:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729301AbgFHKEs (ORCPT ); Mon, 8 Jun 2020 06:04:48 -0400 Received: from laurent.telenet-ops.be (laurent.telenet-ops.be [IPv6:2a02:1800:110:4::f00:19]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 570E7C08C5C5 for ; Mon, 8 Jun 2020 03:04:48 -0700 (PDT) Received: from ramsan ([IPv6:2a02:1810:ac12:ed60:c85f:a5bf:b1bd:702b]) by laurent.telenet-ops.be with bizsmtp id oZzi2200R0R8aca01ZzisA; Mon, 08 Jun 2020 11:59:43 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan with esmtp (Exim 4.90_1) (envelope-from ) id 1jiEZC-0007PB-EI; Mon, 08 Jun 2020 11:59:42 +0200 Received: from geert by rox.of.borg with local (Exim 4.90_1) (envelope-from ) id 1jiEZC-0007xF-Cg; Mon, 08 Jun 2020 11:59:42 +0200 From: Geert Uytterhoeven To: Mark Brown Cc: Chris Brandt , linux-spi@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-sh@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH 4/8] spi: rspi: Increase bit rate accuracy on RZ/A Date: Mon, 8 Jun 2020 11:59:36 +0200 Message-Id: <20200608095940.30516-5-geert+renesas@glider.be> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200608095940.30516-1-geert+renesas@glider.be> References: <20200608095940.30516-1-geert+renesas@glider.be> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org rspi_rz_set_config_register() favors high values of "brdv" over high values of "spbr". As "brdv" is not a plain divider, but controls a power-of-two divider, this may cause the selection of non-optimal divider values. E.g. on RSK+RZA1, when 3.8 MHz is requested, the actual configured bit rate is 2.08 MHz (spbr = 1, brdv = 3), while 3.7 MHz would be possible (spbr = 8, brdv = 0). Fix this by only resorting to higher "brdv" values when really needed. This makes the driver always pick optimal divider values on RZ/A. Signed-off-by: Geert Uytterhoeven --- drivers/spi/spi-rspi.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index 450a42ec2141a895..ad4ac867170b101a 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -298,15 +298,13 @@ static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size) rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); clksrc = clk_get_rate(rspi->clk); - while (brdv < 3) { - if (rspi->speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */ - break; + spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1; + while (spbr > 255 && brdv < 3) { brdv++; - clksrc /= 2; + spbr = DIV_ROUND_UP(spbr + 1, 2) - 1; } /* Sets transfer bit rate */ - spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1; rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); rspi->spcmd |= SPCMD_BRDV(brdv); From patchwork Mon Jun 8 09:59:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 214450 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 A6E98C433E4 for ; Mon, 8 Jun 2020 09:59:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8528D2076C for ; Mon, 8 Jun 2020 09:59:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729259AbgFHJ7r (ORCPT ); Mon, 8 Jun 2020 05:59:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57118 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729330AbgFHJ7p (ORCPT ); Mon, 8 Jun 2020 05:59:45 -0400 Received: from michel.telenet-ops.be (michel.telenet-ops.be [IPv6:2a02:1800:110:4::f00:18]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 544EDC08C5D1 for ; Mon, 8 Jun 2020 02:59:44 -0700 (PDT) Received: from ramsan ([IPv6:2a02:1810:ac12:ed60:c85f:a5bf:b1bd:702b]) by michel.telenet-ops.be with bizsmtp id oZzi2200E0R8aca06Zziop; Mon, 08 Jun 2020 11:59:42 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan with esmtp (Exim 4.90_1) (envelope-from ) id 1jiEZC-0007PE-FS; Mon, 08 Jun 2020 11:59:42 +0200 Received: from geert by rox.of.borg with local (Exim 4.90_1) (envelope-from ) id 1jiEZC-0007xI-Dt; Mon, 08 Jun 2020 11:59:42 +0200 From: Geert Uytterhoeven To: Mark Brown Cc: Chris Brandt , linux-spi@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-sh@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH 5/8] spi: rspi: Increase bit rate range for RSPI on SH Date: Mon, 8 Jun 2020 11:59:37 +0200 Message-Id: <20200608095940.30516-6-geert+renesas@glider.be> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200608095940.30516-1-geert+renesas@glider.be> References: <20200608095940.30516-1-geert+renesas@glider.be> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Increase bit rate range for RSPI on legacy SH by making use of the Bit Rate Frequency Division Setting field in Command Registers, just like is already done on RZ/A. This decreases the lower limit by a factor of 8. Signed-off-by: Geert Uytterhoeven --- Untested due to lack of hardware, but the formulas in the datasheets for SH7753, RZ/A1H, and RZ/A2M are the same. --- drivers/spi/spi-rspi.c | 35 ++++++++++++++++++----------------- 1 file changed, 18 insertions(+), 17 deletions(-) diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index ad4ac867170b101a..ea3f2680d3c13e02 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -248,19 +248,32 @@ struct spi_ops { u8 num_hw_ss; }; +static void rspi_set_rate(struct rspi_data *rspi) +{ + unsigned long clksrc; + int brdv = 0, spbr; + + clksrc = clk_get_rate(rspi->clk); + spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1; + while (spbr > 255 && brdv < 3) { + brdv++; + spbr = DIV_ROUND_UP(spbr + 1, 2) - 1; + } + + rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); + rspi->spcmd |= SPCMD_BRDV(brdv); +} + /* * functions for RSPI on legacy SH */ static int rspi_set_config_register(struct rspi_data *rspi, int access_size) { - int spbr; - /* Sets output mode, MOSI signal, and (optionally) loopback */ rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); /* Sets transfer bit rate */ - spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->speed_hz) - 1; - rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); + rspi_set_rate(rspi); /* Disable dummy transmission, set 16-bit word access, 1 frame */ rspi_write8(rspi, 0, RSPI_SPDCR); @@ -290,23 +303,11 @@ static int rspi_set_config_register(struct rspi_data *rspi, int access_size) */ static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size) { - int spbr; - int brdv = 0; - unsigned long clksrc; - /* Sets output mode, MOSI signal, and (optionally) loopback */ rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); - clksrc = clk_get_rate(rspi->clk); - spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1; - while (spbr > 255 && brdv < 3) { - brdv++; - spbr = DIV_ROUND_UP(spbr + 1, 2) - 1; - } - /* Sets transfer bit rate */ - rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); - rspi->spcmd |= SPCMD_BRDV(brdv); + rspi_set_rate(rspi); /* Disable dummy transmission, set byte access */ rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);