From patchwork Thu Aug 23 13:45:12 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomi Valkeinen X-Patchwork-Id: 1367281 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 5DBB8DF2AB for ; Thu, 23 Aug 2012 13:45:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934020Ab2HWNpx (ORCPT ); Thu, 23 Aug 2012 09:45:53 -0400 Received: from na3sys009aog136.obsmtp.com ([74.125.149.85]:51894 "EHLO na3sys009aog136.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933972Ab2HWNps (ORCPT ); Thu, 23 Aug 2012 09:45:48 -0400 Received: from mail-lpp01m010-f53.google.com ([209.85.215.53]) (using TLSv1) by na3sys009aob136.postini.com ([74.125.148.12]) with SMTP ID DSNKUDY0CHd4rFJYK1437szFbx2L2rgM9zMw@postini.com; Thu, 23 Aug 2012 06:45:47 PDT Received: by lahc1 with SMTP id c1so485698lah.26 for ; Thu, 23 Aug 2012 06:45:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references :x-gm-message-state; bh=eSezpRxYw0kbdsXnWnh0PnEn/8OD+FPglW9qOuqlxZw=; b=XUXEOeKWpbe7AyerODxZyXv1evmCxQ+L+095ostHb6tI+6Z+mh464XaFPIYCF+YOKc QTJgw/keFPQn9KzglhK7eTww2w8XlBfXpr5hZ7ix7rgJIMbKMHmoSvcA2mtsWGZ+roD1 vjNzcJUKzBNG8rHW13pB8PWmP73RYu5QbpwJtS+WnPSJ0mZL3REwCGdgcvQNHFKYScNj dMFzBuDxOvukoJpza+RQRm/sV6eK0fm8ksR+ws9cQTo8pHCo9mvPVCsL8i2YGKhTCW5z HaU0aFmtSrI+M9B6+3sCwd6Lg+OMK86j0m5ZWowsRkZ+4w0GNRrJRx1B788GHNfiD1K7 kqSw== Received: by 10.152.112.34 with SMTP id in2mr1851343lab.6.1345729541379; Thu, 23 Aug 2012 06:45:41 -0700 (PDT) Received: from localhost.localdomain (a91-156-160-115.elisa-laajakaista.fi. [91.156.160.115]) by mx.google.com with ESMTPS id fz8sm466816lbb.9.2012.08.23.06.45.39 (version=SSLv3 cipher=OTHER); Thu, 23 Aug 2012 06:45:40 -0700 (PDT) From: Tomi Valkeinen To: archit@ti.com Cc: linux-omap@vger.kernel.org, linux-fbdev@vger.kernel.org, Tomi Valkeinen Subject: [PATCH 6/8] OMAPDSS: DSI: calculate dsi clock Date: Thu, 23 Aug 2012 16:45:12 +0300 Message-Id: <1345729514-2441-7-git-send-email-tomi.valkeinen@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1345729514-2441-1-git-send-email-tomi.valkeinen@ti.com> References: <1345729514-2441-1-git-send-email-tomi.valkeinen@ti.com> X-Gm-Message-State: ALoCoQn2RvEYVOXY+XkE6whUJj9rwgwxicOkRt/A7ibkiNG3q/8MJn7Yhe8aVEXudPhIJxGNNFti Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Currently the way to configure clocks related to DSI (both DSI and DISPC clocks) happens via omapdss platform data. The reason for this is that configuring the DSS clocks is a very complex problem, and it's impossible for the SW to know requirements about things like interference. However, for general cases it should be fine to calculate the dividers for clocks in the SW. The calculated clocks are probably not perfect, but should work. This patch adds support to calculate the dividers when using DSI command mode panels. The panel gives the required DDR clock rate and LP clock rate, and the DSI driver configures itself and DISPC accordingly. This patch is somewhat ugly, though. The code does its job by modifying the platform data where the clock dividers would be if the board file gave them. This is not how it's going to be in the future, but allows us to have quite simple patch and keep the backward compatibility. It also allows the developer to still give the exact dividers from the board file when there's need for that, as long as the panel driver does not override them. There are also other areas for improvement. For example, it would be better if the panel driver could ask for a DSI clock in a certain range, as, at least command mode panels, the panel can work fine with many different clock speeds. While the patch is not perfect, it allows us to remove the hardcoded clock dividers from the board file, making it easier to bring up a new panel and to use device tree from omapdss. Signed-off-by: Tomi Valkeinen --- drivers/video/omap2/displays/panel-taal.c | 6 ++ drivers/video/omap2/dss/dsi.c | 126 +++++++++++++++++++++++++++++ include/video/omapdss.h | 2 + 3 files changed, 134 insertions(+) diff --git a/drivers/video/omap2/displays/panel-taal.c b/drivers/video/omap2/displays/panel-taal.c index 77aed0e..ddda96a 100644 --- a/drivers/video/omap2/displays/panel-taal.c +++ b/drivers/video/omap2/displays/panel-taal.c @@ -1065,6 +1065,12 @@ static int taal_power_on(struct omap_dss_device *dssdev) omapdss_dsi_set_pixel_format(dssdev, OMAP_DSS_DSI_FMT_RGB888); omapdss_dsi_set_operation_mode(dssdev, OMAP_DSS_DSI_CMD_MODE); + r = omapdss_dsi_set_clocks(dssdev, 216000000, 10000000); + if (r) { + dev_err(&dssdev->dev, "failed to set HS and LP clocks\n"); + goto err0; + } + r = omapdss_dsi_display_enable(dssdev); if (r) { dev_err(&dssdev->dev, "failed to enable DSI\n"); diff --git a/drivers/video/omap2/dss/dsi.c b/drivers/video/omap2/dss/dsi.c index 96d0024..340c832 100644 --- a/drivers/video/omap2/dss/dsi.c +++ b/drivers/video/omap2/dss/dsi.c @@ -1454,6 +1454,68 @@ found: return 0; } +static int dsi_pll_calc_ddrfreq(struct platform_device *dsidev, + unsigned long req_clk, struct dsi_clock_info *cinfo) +{ + struct dsi_data *dsi = dsi_get_dsidrv_data(dsidev); + struct dsi_clock_info cur, best; + unsigned long dss_sys_clk, max_dss_fck, max_dsi_fck; + unsigned long req_clkin4ddr; + + DSSDBG("dsi_pll_calc_ddrfreq\n"); + + dss_sys_clk = clk_get_rate(dsi->sys_clk); + + max_dss_fck = dss_feat_get_param_max(FEAT_PARAM_DSS_FCK); + max_dsi_fck = dss_feat_get_param_max(FEAT_PARAM_DSI_FCK); + + memset(&best, 0, sizeof(best)); + memset(&cur, 0, sizeof(cur)); + + cur.clkin = dss_sys_clk; + + req_clkin4ddr = req_clk * 4; + + for (cur.regn = 1; cur.regn < dsi->regn_max; ++cur.regn) { + cur.fint = cur.clkin / cur.regn; + + if (cur.fint > dsi->fint_max || cur.fint < dsi->fint_min) + continue; + + /* DSIPHY(MHz) = (2 * regm / regn) * clkin */ + for (cur.regm = 1; cur.regm < dsi->regm_max; ++cur.regm) { + unsigned long a, b; + + a = 2 * cur.regm * (cur.clkin/1000); + b = cur.regn; + cur.clkin4ddr = a / b * 1000; + + if (cur.clkin4ddr > 1800 * 1000 * 1000) + break; + + if (abs(cur.clkin4ddr - req_clkin4ddr) < + abs(best.clkin4ddr - req_clkin4ddr)) { + best = cur; + DSSDBG("best %ld\n", best.clkin4ddr); + } + + if (cur.clkin4ddr == req_clkin4ddr) + goto found; + } + } +found: + best.regm_dispc = DIV_ROUND_UP(best.clkin4ddr, max_dss_fck); + best.dsi_pll_hsdiv_dispc_clk = best.clkin4ddr / best.regm_dispc; + + best.regm_dsi = DIV_ROUND_UP(best.clkin4ddr, max_dsi_fck); + best.dsi_pll_hsdiv_dsi_clk = best.clkin4ddr / best.regm_dsi; + + if (cinfo) + *cinfo = best; + + return 0; +} + int dsi_pll_set_clock_div(struct platform_device *dsidev, struct dsi_clock_info *cinfo) { @@ -4110,6 +4172,70 @@ int omapdss_dsi_configure_pins(struct omap_dss_device *dssdev, } EXPORT_SYMBOL(omapdss_dsi_configure_pins); +int omapdss_dsi_set_clocks(struct omap_dss_device *dssdev, + unsigned long ddr_clk, unsigned long lp_clk) +{ + struct platform_device *dsidev = dsi_get_dsidev_from_dssdev(dssdev); + struct dsi_data *dsi = dsi_get_dsidrv_data(dsidev); + struct dsi_clock_info cinfo; + struct dispc_clock_info dispc_cinfo; + unsigned lp_clk_div; + unsigned long dsi_fclk; + int bpp = dsi_get_pixel_size(dssdev->panel.dsi_pix_fmt); + unsigned long pck; + int r; + + DSSDBGF("ddr_clk %lu, lp_clk %lu", ddr_clk, lp_clk); + + mutex_lock(&dsi->lock); + + r = dsi_pll_calc_ddrfreq(dsidev, ddr_clk, &cinfo); + if (r) + goto err; + + dssdev->clocks.dsi.regn = cinfo.regn; + dssdev->clocks.dsi.regm = cinfo.regm; + dssdev->clocks.dsi.regm_dispc = cinfo.regm_dispc; + dssdev->clocks.dsi.regm_dsi = cinfo.regm_dsi; + + + dsi_fclk = cinfo.dsi_pll_hsdiv_dsi_clk; + lp_clk_div = DIV_ROUND_UP(dsi_fclk, lp_clk * 2); + + dssdev->clocks.dsi.lp_clk_div = lp_clk_div; + + /* pck = TxByteClkHS * datalanes * 8 / bitsperpixel */ + + pck = cinfo.clkin4ddr / 16 * (dsi->num_lanes_used - 1) * 8 / bpp; + + DSSDBG("finding dispc dividers for pck %lu\n", pck); + + dispc_find_clk_divs(pck, cinfo.dsi_pll_hsdiv_dispc_clk, &dispc_cinfo); + + dssdev->clocks.dispc.channel.lck_div = dispc_cinfo.lck_div; + dssdev->clocks.dispc.channel.pck_div = dispc_cinfo.pck_div; + + + dssdev->clocks.dispc.dispc_fclk_src = OMAP_DSS_CLK_SRC_FCK; + + dssdev->clocks.dispc.channel.lcd_clk_src = + dsi->module_id == 0 ? + OMAP_DSS_CLK_SRC_DSI_PLL_HSDIV_DISPC : + OMAP_DSS_CLK_SRC_DSI2_PLL_HSDIV_DISPC; + + dssdev->clocks.dsi.dsi_fclk_src = + dsi->module_id == 0 ? + OMAP_DSS_CLK_SRC_DSI_PLL_HSDIV_DSI : + OMAP_DSS_CLK_SRC_DSI2_PLL_HSDIV_DSI; + + mutex_unlock(&dsi->lock); + return 0; +err: + mutex_unlock(&dsi->lock); + return r; +} +EXPORT_SYMBOL(omapdss_dsi_set_clocks); + int dsi_enable_video_output(struct omap_dss_device *dssdev, int channel) { struct platform_device *dsidev = dsi_get_dsidev_from_dssdev(dssdev); diff --git a/include/video/omapdss.h b/include/video/omapdss.h index c6ffe88..8a926f8 100644 --- a/include/video/omapdss.h +++ b/include/video/omapdss.h @@ -738,6 +738,8 @@ int omap_dsi_set_vc_id(struct omap_dss_device *dssdev, int channel, int vc_id); void omap_dsi_release_vc(struct omap_dss_device *dssdev, int channel); int omapdss_dsi_configure_pins(struct omap_dss_device *dssdev, const struct omap_dsi_pin_config *pin_cfg); +int omapdss_dsi_set_clocks(struct omap_dss_device *dssdev, + unsigned long ddr_clk, unsigned long lp_clk); int omapdss_dsi_display_enable(struct omap_dss_device *dssdev); void omapdss_dsi_display_disable(struct omap_dss_device *dssdev,