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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 6A44CC64EB1 for ; Fri, 7 Dec 2018 13:56:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 324D820837 for ; Fri, 7 Dec 2018 13:56:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 324D820837 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726284AbeLGN4j (ORCPT ); Fri, 7 Dec 2018 08:56:39 -0500 Received: from mail.bootlin.com ([62.4.15.54]:58720 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726159AbeLGN4D (ORCPT ); Fri, 7 Dec 2018 08:56:03 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id 8202A20E2C; Fri, 7 Dec 2018 14:56:01 +0100 (CET) Received: from localhost (aaubervilliers-681-1-79-44.w90-88.abo.wanadoo.fr [90.88.21.44]) by mail.bootlin.com (Postfix) with ESMTPSA id 199DB20CDF; Fri, 7 Dec 2018 14:55:43 +0100 (CET) From: Maxime Ripard To: Kishon Vijay Abraham I , Boris Brezillon Cc: Thomas Petazzoni , Laurent Pinchart , linux-media@vger.kernel.org, Archit Taneja , Andrzej Hajda , Chen-Yu Tsai , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, Krzysztof Witos , Rafal Ciepiela , Maxime Ripard Subject: [PATCH v3 04/10] phy: dphy: Add configuration helpers Date: Fri, 7 Dec 2018 14:55:31 +0100 Message-Id: <0dffe403b8df150746c57c067afe1f4a8c262200.1544190837.git-series.maxime.ripard@bootlin.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The MIPI D-PHY spec defines default values and boundaries for most of the parameters it defines. Introduce helpers to help drivers get meaningful values based on their current parameters, and validate the boundaries of these parameters if needed. Signed-off-by: Maxime Ripard --- drivers/phy/Kconfig | 8 +- drivers/phy/Makefile | 1 +- drivers/phy/phy-core-mipi-dphy.c | 166 +++++++++++++++++++++++++++++++- include/linux/phy/phy-mipi-dphy.h | 6 +- 4 files changed, 181 insertions(+) create mode 100644 drivers/phy/phy-core-mipi-dphy.c diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig index 60f949e2a684..c87a7d49eaab 100644 --- a/drivers/phy/Kconfig +++ b/drivers/phy/Kconfig @@ -15,6 +15,14 @@ config GENERIC_PHY phy users can obtain reference to the PHY. All the users of this framework should select this config. +config GENERIC_PHY_MIPI_DPHY + bool + help + Generic MIPI D-PHY support. + + Provides a number of helpers a core functions for MIPI D-PHY + drivers to us. + config PHY_LPC18XX_USB_OTG tristate "NXP LPC18xx/43xx SoC USB OTG PHY driver" depends on OF && (ARCH_LPC18XX || COMPILE_TEST) diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile index 0301e25d07c1..baec59cebbab 100644 --- a/drivers/phy/Makefile +++ b/drivers/phy/Makefile @@ -4,6 +4,7 @@ # obj-$(CONFIG_GENERIC_PHY) += phy-core.o +obj-$(CONFIG_GENERIC_PHY_MIPI_DPHY) += phy-core-mipi-dphy.o obj-$(CONFIG_PHY_LPC18XX_USB_OTG) += phy-lpc18xx-usb-otg.o obj-$(CONFIG_PHY_XGENE) += phy-xgene.o obj-$(CONFIG_PHY_PISTACHIO_USB) += phy-pistachio-usb.o diff --git a/drivers/phy/phy-core-mipi-dphy.c b/drivers/phy/phy-core-mipi-dphy.c new file mode 100644 index 000000000000..465fa1b91a5f --- /dev/null +++ b/drivers/phy/phy-core-mipi-dphy.c @@ -0,0 +1,166 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2013 NVIDIA Corporation + * Copyright (C) 2018 Cadence Design Systems Inc. + */ + +#include +#include +#include +#include + +#include +#include + +#define PSEC_PER_SEC 1000000000000LL + +/* + * Minimum D-PHY timings based on MIPI D-PHY specification. Derived + * from the valid ranges specified in Section 6.9, Table 14, Page 41 + * of the D-PHY specification (v2.1). + */ +int phy_mipi_dphy_get_default_config(unsigned long pixel_clock, + unsigned int bpp, + unsigned int lanes, + struct phy_configure_opts_mipi_dphy *cfg) +{ + unsigned long long hs_clk_rate; + unsigned long long ui; + + if (!cfg) + return -EINVAL; + + hs_clk_rate = pixel_clock * bpp; + do_div(hs_clk_rate, lanes); + + ui = ALIGN(PSEC_PER_SEC, hs_clk_rate); + do_div(ui, hs_clk_rate); + + cfg->clk_miss = 0; + cfg->clk_post = 60000 + 52 * ui; + cfg->clk_pre = 8000; + cfg->clk_prepare = 38000; + cfg->clk_settle = 95000; + cfg->clk_term_en = 0; + cfg->clk_trail = 60000; + cfg->clk_zero = 262000; + cfg->d_term_en = 0; + cfg->eot = 0; + cfg->hs_exit = 100000; + cfg->hs_prepare = 40000 + 4 * ui; + cfg->hs_zero = 105000 + 6 * ui; + cfg->hs_settle = 85000 + 6 * ui; + cfg->hs_skip = 40000; + + /* + * The MIPI D-PHY specification (Section 6.9, v1.2, Table 14, Page 40) + * contains this formula as: + * + * T_HS-TRAIL = max(n * 8 * ui, 60 + n * 4 * ui) + * + * where n = 1 for forward-direction HS mode and n = 4 for reverse- + * direction HS mode. There's only one setting and this function does + * not parameterize on anything other that ui, so this code will + * assumes that reverse-direction HS mode is supported and uses n = 4. + */ + cfg->hs_trail = max(4 * 8 * ui, 60000 + 4 * 4 * ui); + + cfg->init = 100000000; + cfg->lpx = 60000; + cfg->ta_get = 5 * cfg->lpx; + cfg->ta_go = 4 * cfg->lpx; + cfg->ta_sure = 2 * cfg->lpx; + cfg->wakeup = 1000000000; + + cfg->hs_clk_rate = hs_clk_rate; + cfg->lanes = lanes; + + return 0; +} +EXPORT_SYMBOL(phy_mipi_dphy_get_default_config); + +/* + * Validate D-PHY configuration according to MIPI D-PHY specification + * (v1.2, Section Section 6.9 "Global Operation Timing Parameters"). + */ +int phy_mipi_dphy_config_validate(struct phy_configure_opts_mipi_dphy *cfg) +{ + unsigned long long ui; + + if (!cfg) + return -EINVAL; + + ui = ALIGN(PSEC_PER_SEC, cfg->hs_clk_rate); + do_div(ui, cfg->hs_clk_rate); + + if (cfg->clk_miss > 60000) + return -EINVAL; + + if (cfg->clk_post < (60000 + 52 * ui)) + return -EINVAL; + + if (cfg->clk_pre < 8000) + return -EINVAL; + + if (cfg->clk_prepare < 38000 || cfg->clk_prepare > 95000) + return -EINVAL; + + if (cfg->clk_settle < 95000 || cfg->clk_settle > 300000) + return -EINVAL; + + if (cfg->clk_term_en > 38000) + return -EINVAL; + + if (cfg->clk_trail < 60000) + return -EINVAL; + + if ((cfg->clk_prepare + cfg->clk_zero) < 300000) + return -EINVAL; + + if (cfg->d_term_en > (35000 + 4 * ui)) + return -EINVAL; + + if (cfg->eot > (105000 + 12 * ui)) + return -EINVAL; + + if (cfg->hs_exit < 100000) + return -EINVAL; + + if (cfg->hs_prepare < (40000 + 4 * ui) || + cfg->hs_prepare > (85000 + 6 * ui)) + return -EINVAL; + + if ((cfg->hs_prepare + cfg->hs_zero) < (145000 + 10 * ui)) + return -EINVAL; + + if ((cfg->hs_settle < (85000 + 6 * ui)) || + (cfg->hs_settle > (145000 + 10 * ui))) + return -EINVAL; + + if (cfg->hs_skip < 40000 || cfg->hs_skip > (55000 + 4 * ui)) + return -EINVAL; + + if (cfg->hs_trail < max(8 * ui, 60000 + 4 * ui)) + return -EINVAL; + + if (cfg->init < 100000000) + return -EINVAL; + + if (cfg->lpx < 50000) + return -EINVAL; + + if (cfg->ta_get != (5 * cfg->lpx)) + return -EINVAL; + + if (cfg->ta_go != (4 * cfg->lpx)) + return -EINVAL; + + if (cfg->ta_sure < cfg->lpx || cfg->ta_sure > (2 * cfg->lpx)) + return -EINVAL; + + if (cfg->wakeup < 1000000000) + return -EINVAL; + + return 0; +} +EXPORT_SYMBOL(phy_mipi_dphy_config_validate); diff --git a/include/linux/phy/phy-mipi-dphy.h b/include/linux/phy/phy-mipi-dphy.h index 29bf94db88ad..c08aacc0ac35 100644 --- a/include/linux/phy/phy-mipi-dphy.h +++ b/include/linux/phy/phy-mipi-dphy.h @@ -276,4 +276,10 @@ struct phy_configure_opts_mipi_dphy { unsigned char lanes; }; +int phy_mipi_dphy_get_default_config(unsigned long pixel_clock, + unsigned int bpp, + unsigned int lanes, + struct phy_configure_opts_mipi_dphy *cfg); +int phy_mipi_dphy_config_validate(struct phy_configure_opts_mipi_dphy *cfg); + #endif /* __PHY_MIPI_DPHY_H_ */ -- git-series 0.9.1