From patchwork Wed Feb 24 16:48:35 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jyri Sarha X-Patchwork-Id: 62806 Delivered-To: patch@linaro.org Received: by 10.112.43.199 with SMTP id y7csp2513898lbl; Wed, 24 Feb 2016 08:49:13 -0800 (PST) X-Received: by 10.66.55.39 with SMTP id o7mr55272353pap.13.1456332551897; Wed, 24 Feb 2016 08:49:11 -0800 (PST) Return-Path: Received: from gabe.freedesktop.org (gabe.freedesktop.org. [2610:10:20:722:a800:ff:fe36:1795]) by mx.google.com with ESMTP id 68si5964844pfj.77.2016.02.24.08.49.11; Wed, 24 Feb 2016 08:49:11 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 as permitted sender) client-ip=2610:10:20:722:a800:ff:fe36:1795; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 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 B00F76E7F0; Wed, 24 Feb 2016 16:49:10 +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 140776E7F8 for ; Wed, 24 Feb 2016 16:49:07 +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 u1OGn3JH010199; Wed, 24 Feb 2016 10:49:03 -0600 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id u1OGn2B7005497; Wed, 24 Feb 2016 10:49:03 -0600 Received: from dflp32.itg.ti.com (10.64.6.15) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.3.224.2; Wed, 24 Feb 2016 10:49:02 -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 u1OGmwiY009536; Wed, 24 Feb 2016 10:49:01 -0600 From: Jyri Sarha To: Subject: [PATCH v4 01/22] drm/tilcdc: rewrite pixel clock calculation Date: Wed, 24 Feb 2016 18:48:35 +0200 Message-ID: <92d35c80d39c28181d94a2e8979f7b4db772272d.1456331965.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 4802da8..aaf8989 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 8190ac3..b3dbbe9 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 66105d8..62a1d68 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 */