From patchwork Tue Feb 16 14:18:18 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jyri Sarha X-Patchwork-Id: 62026 Delivered-To: patch@linaro.org Received: by 10.112.43.199 with SMTP id y7csp1691415lbl; Tue, 16 Feb 2016 06:18:56 -0800 (PST) X-Received: by 10.98.93.205 with SMTP id n74mr6908561pfj.99.1455632335897; Tue, 16 Feb 2016 06:18:55 -0800 (PST) Return-Path: Received: from gabe.freedesktop.org (gabe.freedesktop.org. [131.252.210.177]) by mx.google.com with ESMTP id la16si51479305pab.64.2016.02.16.06.18.55; Tue, 16 Feb 2016 06:18:55 -0800 (PST) Received-SPF: pass (google.com: best guess record for 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: best guess record for 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 BC4E26E7E5; Tue, 16 Feb 2016 14:18:54 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from arroyo.ext.ti.com (arroyo.ext.ti.com [192.94.94.40]) by gabe.freedesktop.org (Postfix) with ESMTPS id A1EC26E7F2 for ; Tue, 16 Feb 2016 14:18:52 +0000 (UTC) Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id u1GEIkR3028578; Tue, 16 Feb 2016 08:18:46 -0600 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id u1GEIkq9031754; Tue, 16 Feb 2016 08:18:46 -0600 Received: from dflp32.itg.ti.com (10.64.6.15) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.3.224.2; Tue, 16 Feb 2016 08:18:45 -0600 Received: from imryr.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id u1GEIftK011585; Tue, 16 Feb 2016 08:18:44 -0600 From: Jyri Sarha To: Subject: [PATCH v2 01/21] drm/tilcdc: rewrite pixel clock calculation Date: Tue, 16 Feb 2016 16:18:18 +0200 Message-ID: <3259f1e149abb34349d1a9803e5c39c2e2da1196.1455632042.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 d7f5b89..4d75ee3 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c @@ -192,13 +192,6 @@ 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; @@ -206,7 +199,7 @@ 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 @@ -330,8 +323,6 @@ 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 */