From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754211AbdLDQHr (ORCPT ); Mon, 4 Dec 2017 11:07:47 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:35774 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753647AbdLDQHm (ORCPT ); Mon, 4 Dec 2017 11:07:42 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kevin Hao , Jyri Sarha , Tomi Valkeinen Subject: [PATCH 4.14 73/95] drm/tilcdc: Precalculate total frametime in tilcdc_crtc_set_mode() Date: Mon, 4 Dec 2017 17:00:37 +0100 Message-Id: <20171204160049.079652883@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171204160046.206920966@linuxfoundation.org> References: <20171204160046.206920966@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jyri Sarha commit ce99f7206c9105851d97202ed08c058af6f11ac4 upstream. We need the total frame refresh time to check if we are too close to vertical sync when updating the two framebuffer DMA registers and risk a collision. This new method is more accurate that the previous that based on mode's vrefresh value, which itself is inaccurate or may not even be initialized. Reported-by: Kevin Hao Fixes: 11abbc9f39e0 ("drm/tilcdc: Set framebuffer DMA address to HW only if CRTC is enabled") Signed-off-by: Jyri Sarha Reviewed-by: Tomi Valkeinen Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/tilcdc/tilcdc_crtc.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c @@ -24,6 +24,7 @@ #include #include #include +#include #include "tilcdc_drv.h" #include "tilcdc_regs.h" @@ -48,6 +49,7 @@ struct tilcdc_crtc { unsigned int lcd_fck_rate; ktime_t last_vblank; + unsigned int hvtotal_us; struct drm_framebuffer *curr_fb; struct drm_framebuffer *next_fb; @@ -292,6 +294,12 @@ static void tilcdc_crtc_set_clk(struct d LCDC_V2_CORE_CLK_EN); } +uint tilcdc_mode_hvtotal(const struct drm_display_mode *mode) +{ + return (uint) div_u64(1000llu * mode->htotal * mode->vtotal, + mode->clock); +} + static void tilcdc_crtc_set_mode(struct drm_crtc *crtc) { struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc); @@ -459,6 +467,9 @@ static void tilcdc_crtc_set_mode(struct drm_framebuffer_reference(fb); crtc->hwmode = crtc->state->adjusted_mode; + + tilcdc_crtc->hvtotal_us = + tilcdc_mode_hvtotal(&crtc->hwmode); } static void tilcdc_crtc_enable(struct drm_crtc *crtc) @@ -648,7 +659,7 @@ int tilcdc_crtc_update_fb(struct drm_crt spin_lock_irqsave(&tilcdc_crtc->irq_lock, flags); next_vblank = ktime_add_us(tilcdc_crtc->last_vblank, - 1000000 / crtc->hwmode.vrefresh); + tilcdc_crtc->hvtotal_us); tdiff = ktime_to_us(ktime_sub(next_vblank, ktime_get())); if (tdiff < TILCDC_VBLANK_SAFETY_THRESHOLD_US)