From patchwork Tue Dec 15 19:03:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jyri Sarha X-Patchwork-Id: 58451 Delivered-To: patch@linaro.org Received: by 10.112.89.199 with SMTP id bq7csp233461lbb; Tue, 15 Dec 2015 11:03:50 -0800 (PST) X-Received: by 10.98.87.83 with SMTP id l80mr46954533pfb.126.1450206230619; Tue, 15 Dec 2015 11:03:50 -0800 (PST) Return-Path: Received: from gabe.freedesktop.org (gabe.freedesktop.org. [131.252.210.177]) by mx.google.com with ESMTP id e86si3428290pfj.161.2015.12.15.11.03.50; Tue, 15 Dec 2015 11:03:50 -0800 (PST) Received-SPF: pass (google.com: domain of dri-devel-bounces@lists.freedesktop.org designates 131.252.210.177 as permitted sender) client-ip=131.252.210.177; Authentication-Results: mx.google.com; spf=pass (google.com: domain of dri-devel-bounces@lists.freedesktop.org designates 131.252.210.177 as permitted sender) smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7D7126E77B; Tue, 15 Dec 2015 11:03:49 -0800 (PST) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from devils.ext.ti.com (devils.ext.ti.com [198.47.26.153]) by gabe.freedesktop.org (Postfix) with ESMTPS id 437706E77B for ; Tue, 15 Dec 2015 11:03:48 -0800 (PST) Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by devils.ext.ti.com (8.13.7/8.13.7) with ESMTP id tBFJ3ih9028333; Tue, 15 Dec 2015 13:03:44 -0600 Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id tBFJ3iMZ013832; Tue, 15 Dec 2015 13:03:44 -0600 Received: from dlep32.itg.ti.com (157.170.170.100) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.3.224.2; Tue, 15 Dec 2015 13:03:44 -0600 Received: from imryr.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep32.itg.ti.com (8.14.3/8.13.8) with ESMTP id tBFJ3bas015462; Tue, 15 Dec 2015 13:03:42 -0600 From: Jyri Sarha To: Subject: [PATCH 02/12] drm/tilcdc: rewrite pixel clock calculation Date: Tue, 15 Dec 2015 21:03:13 +0200 Message-ID: <73b116cc366a36a4f3ebf2b57977dd12d8171073.1450202735.git.jsarha@ti.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: MIME-Version: 1.0 Cc: Jyri Sarha , Darren Etheridge , tomi.valkeinen@ti.com, laurent.pinchart@ideasonboard.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Darren Etheridge Updating the tilcdc DRM driver code to calculate the LCD controller pixel clock more accurately. Based on a suggested implementation by Tomi Valkeinen. The current code does not work correctly and produces wrong results with many requested clock rates. It also oddly uses two different clocks, a display pll clock and a divider clock (child of display pll), instead of just using the clock coming to the lcdc. This patch removes the use of the display pll clock, and rewrites the code to calculate the clock rates. The idea is simply to request a clock rate of pixelclock*2, as the LCD controller has an internal divider which we set to 2. Signed-off-by: Darren Etheridge [Rewrapped description] Signed-off-by: Jyri Sarha --- drivers/gpu/drm/tilcdc/tilcdc_crtc.c | 16 ++++++++-------- drivers/gpu/drm/tilcdc/tilcdc_drv.c | 11 +---------- drivers/gpu/drm/tilcdc/tilcdc_drv.h | 1 - 3 files changed, 9 insertions(+), 19 deletions(-) diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c index 7d07733..7b687ae 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c @@ -573,7 +573,8 @@ void tilcdc_crtc_update_clk(struct drm_crtc *crtc) struct drm_device *dev = crtc->dev; struct tilcdc_drm_private *priv = dev->dev_private; int dpms = tilcdc_crtc->dpms; - unsigned int lcd_clk, div; + unsigned long lcd_clk; + const unsigned clkdiv = 2; /* using a fixed divider of 2 */ int ret; pm_runtime_get_sync(dev->dev); @@ -581,22 +582,21 @@ void tilcdc_crtc_update_clk(struct drm_crtc *crtc) if (dpms == DRM_MODE_DPMS_ON) tilcdc_crtc_dpms(crtc, DRM_MODE_DPMS_OFF); - /* in raster mode, minimum divisor is 2: */ - ret = clk_set_rate(priv->disp_clk, crtc->mode.clock * 1000 * 2); - if (ret) { + /* mode.clock is in KHz, set_rate wants parameter in Hz */ + ret = clk_set_rate(priv->clk, crtc->mode.clock * 1000 * clkdiv); + if (ret < 0) { dev_err(dev->dev, "failed to set display clock rate to: %d\n", crtc->mode.clock); goto out; } lcd_clk = clk_get_rate(priv->clk); - div = lcd_clk / (crtc->mode.clock * 1000); - DBG("lcd_clk=%u, mode clock=%d, div=%u", lcd_clk, crtc->mode.clock, div); - DBG("fck=%lu, dpll_disp_ck=%lu", clk_get_rate(priv->clk), clk_get_rate(priv->disp_clk)); + DBG("lcd_clk=%lu, mode clock=%d, div=%u", + lcd_clk, crtc->mode.clock, clkdiv); /* Configure the LCD clock divisor. */ - tilcdc_write(dev, LCDC_CTRL_REG, LCDC_CLK_DIVISOR(div) | + tilcdc_write(dev, LCDC_CTRL_REG, LCDC_CLK_DIVISOR(clkdiv) | LCDC_RASTER_MODE); if (priv->rev == 2) diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c index 02525b2..2b2780e 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c @@ -193,13 +193,6 @@ static int tilcdc_load(struct drm_device *dev, unsigned long flags) goto fail_iounmap; } - priv->disp_clk = clk_get(dev->dev, "dpll_disp_ck"); - if (IS_ERR(priv->clk)) { - dev_err(dev->dev, "failed to get display clock\n"); - ret = -ENODEV; - goto fail_put_clk; - } - #ifdef CONFIG_CPU_FREQ priv->lcd_fck_rate = clk_get_rate(priv->clk); priv->freq_transition.notifier_call = cpufreq_transition; @@ -207,7 +200,7 @@ static int tilcdc_load(struct drm_device *dev, unsigned long flags) CPUFREQ_TRANSITION_NOTIFIER); if (ret) { dev_err(dev->dev, "failed to register cpufreq notifier\n"); - goto fail_put_disp_clk; + goto fail_put_clk; } #endif @@ -338,8 +331,6 @@ fail_cpufreq_unregister: #ifdef CONFIG_CPU_FREQ cpufreq_unregister_notifier(&priv->freq_transition, CPUFREQ_TRANSITION_NOTIFIER); -fail_put_disp_clk: - clk_put(priv->disp_clk); #endif fail_put_clk: diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.h b/drivers/gpu/drm/tilcdc/tilcdc_drv.h index e863ad0..c00f518 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.h +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.h @@ -49,7 +49,6 @@ struct tilcdc_drm_private { void __iomem *mmio; - struct clk *disp_clk; /* display dpll */ struct clk *clk; /* functional clock */ int rev; /* IP revision */