From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 88271427A06 for ; Tue, 19 May 2026 09:02:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=68.232.154.123 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779181339; cv=none; b=lZLXtZmf7ORVglgfP3mhOSst1fI6BMoMF/BL5CwAV1CEHvnm8guvepfn+Btm3i2Gq17YGN1HqHgHpSylqCwiIF7zBjLZ4hqS3b2xqaRU8RQE5dInQo2cWS/eM8Q2YTzP11labQA3B4nACWEPkKUU2Z6yMul0Ad2ne69lirVToc4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779181339; c=relaxed/simple; bh=GN9Elk55Ckw9oiHQjukAbkq2ymh10RJ8TnEXN6zUYIA=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=QWhakNDRvNyuq6aX0OOPkkU2iaVOzavyzk0IutV9xb8IfW+/RC/ZJmTA8YMUKPHE+5VGR53HFl4vXexAfYEUik4qhGnC9HvvDp7sy9xpaZNqtj7fUElTrrC1YJLzxEkBdLofWZwmQXkiZwDrW6AjGqNZizmfMorjltiR7Fttws8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com; spf=pass smtp.mailfrom=microchip.com; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b=vxaIDucg; arc=none smtp.client-ip=68.232.154.123 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=microchip.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b="vxaIDucg" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1779181338; x=1810717338; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=GN9Elk55Ckw9oiHQjukAbkq2ymh10RJ8TnEXN6zUYIA=; b=vxaIDucgvdVv4mccruMZjCUPWhT7MvHnrVeSu/eF+p1ZIreXRa9x23ee EXq2WqDOVE9BwhAhsHGpHxRwqLA6RzXtV2wFjIlVAJHH4eRzBifZVZatL CG4QCZEgv93p3YxwqbKXNI+2svjNgLgOD9uxdpZkuvIu8ouQ3UgzXfux4 BXvevjjxKQmgm6SewRmDMTVk3V/+rG0DThVTqAhfX6AQe7LtjEhAVj8u+ sugHJb6U7uKsgH5VGOWPl3zie2vmMTC8ZfOOTEpubq58ir+aBESFCm59L sLEX5sYUJ46EkP2542BCOJnoUoK3l0iOd2xuCRXiRZx6WjaQKJzoikq9i g==; X-CSE-ConnectionGUID: cRB7afV+QCu/Kd7rCmC/lA== X-CSE-MsgGUID: VBVl8s9QTi+FiNqzdZOfJg== X-IronPort-AV: E=Sophos;i="6.23,243,1770620400"; d="scan'208";a="224955560" X-Amp-Result: SKIPPED(no attachment in message) Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa6.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 19 May 2026 02:02:16 -0700 Received: from chn-vm-ex04.mchp-main.com (10.10.85.152) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.58; Tue, 19 May 2026 02:02:17 -0700 Received: from che-lt-i67131.microchip.com (10.10.85.11) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server id 15.1.2507.58 via Frontend Transport; Tue, 19 May 2026 02:02:12 -0700 From: Manikandan Muralidharan To: , , , , , , , , , , , CC: Subject: [PATCH 4/8] drm: atmel-hlcdc: define ATMEL_HLCDC_CLKDIV_MAX and fix divider fallback Date: Tue, 19 May 2026 14:31:31 +0530 Message-ID: <20260519090135.1188405-5-manikandan.m@microchip.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260519090135.1188405-1-manikandan.m@microchip.com> References: <20260519090135.1188405-1-manikandan.m@microchip.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain Introduce ATMEL_HLCDC_CLKDIV_MAX to replace the raw mask.In the divider overflow fallback, restrict the clock source switch and halved rate retry to SoCs that support the 2x system clock path. Signed-off-by: Manikandan Muralidharan --- drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c | 9 +++++---- include/linux/mfd/atmel-hlcdc.h | 1 + 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c index f30138da1ed8..c7e77bb2941a 100644 --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c @@ -117,11 +117,12 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c) div = 2; } else if (ATMEL_HLCDC_CLKDIV(div) & ~ATMEL_HLCDC_CLKDIV_MASK) { /* The divider ended up too big, try a lower base rate. */ - cfg &= ~ATMEL_HLCDC_CLKSEL; - prate /= 2; - div = DIV_ROUND_CLOSEST(prate, mode_rate); + if (!crtc->dc->desc->fixed_clksrc) { + cfg &= ~ATMEL_HLCDC_CLKSEL; + div = DIV_ROUND_CLOSEST(prate >> 1, mode_rate); + } if (ATMEL_HLCDC_CLKDIV(div) & ~ATMEL_HLCDC_CLKDIV_MASK) - div = ATMEL_HLCDC_CLKDIV_MASK; + div = ATMEL_HLCDC_CLKDIV_MAX; } cfg |= ATMEL_HLCDC_CLKDIV(div); diff --git a/include/linux/mfd/atmel-hlcdc.h b/include/linux/mfd/atmel-hlcdc.h index 07c2081867fd..8e86219293b7 100644 --- a/include/linux/mfd/atmel-hlcdc.h +++ b/include/linux/mfd/atmel-hlcdc.h @@ -50,6 +50,7 @@ #define ATMEL_HLCDC_CLKDIV_SHFT 16 #define ATMEL_HLCDC_CLKDIV_MASK GENMASK(23, 16) #define ATMEL_HLCDC_CLKDIV(div) ((div - 2) << ATMEL_HLCDC_CLKDIV_SHFT) +#define ATMEL_HLCDC_CLKDIV_MAX ((ATMEL_HLCDC_CLKDIV_MASK >> ATMEL_HLCDC_CLKDIV_SHFT) + 2) #define ATMEL_HLCDC_PIXEL_CLK BIT(0) #define ATMEL_HLCDC_SYNC BIT(1) -- 2.25.1