From nobody Mon Feb 9 16:17:49 2026 Received: from lelvem-ot01.ext.ti.com (lelvem-ot01.ext.ti.com [198.47.23.234]) (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 019E032548D for ; Mon, 27 Oct 2025 21:27:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.47.23.234 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761600445; cv=none; b=D/HzH2YQK6Uc67Y06jTs/iUs0kOfOLZEmeOkQ3lF8+nKBxwPQz3QPxvKamw5jSHSDuV5CGdPTkUrdbclHROJH2Ucw0rtS85wBJzLAUZN2E5QSNcM56zpLjiSLUGte0EBYQ3fHpcx49ElhL+8xjwrmZJthlxhGWmnQn25QkGdW4g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761600445; c=relaxed/simple; bh=DNq4+3TXq9EfjM7kdNigYuP8GMWIJc/TUvBGaZPD+5g=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=r4/xoQ++BCujHIT9vfHJWqwp2ule9yJeS7vXjS/7rDmX+71cLLrr3lNCp+3e75Zt5zIEkwUcbpv8S2Vg2WIWmPn08SXYJ5+7wjRIrSS0GoQt6MOHI8XwMim8+fEoCFxBZrD+Fp+HBSHHGrc3IvDaEMJFQVvTrwj10PvIe1OKjsg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com; spf=pass smtp.mailfrom=ti.com; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b=Qm41IJFn; arc=none smtp.client-ip=198.47.23.234 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ti.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="Qm41IJFn" Received: from lelvem-sh02.itg.ti.com ([10.180.78.226]) by lelvem-ot01.ext.ti.com (8.15.2/8.15.2) with ESMTP id 59RLQZoK2510202; Mon, 27 Oct 2025 16:26:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1761600395; bh=8YsUL3FmjkiSJTuL3XXGj1pESxfnhDNRpNWlSDg3YYA=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=Qm41IJFnF3d0KN7Yvfyzbtt1M2pt6oftCktDt1JWdTvloXqesuQsHuKgOHqb4FLlh /ABdUZ4vtNLB0P3gojeSMtCz2iZ6KLM3lppEBDkXgZGoj9Mz9m1XJgVCygNfAVVRQk bd422PDim/xfCT2jKTQjeCJETbWFI2Hy4kpkQWNM= Received: from DLEE214.ent.ti.com (dlee214.ent.ti.com [157.170.170.117]) by lelvem-sh02.itg.ti.com (8.18.1/8.18.1) with ESMTPS id 59RLQYgL1916754 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 27 Oct 2025 16:26:34 -0500 Received: from DLEE212.ent.ti.com (157.170.170.114) by DLEE214.ent.ti.com (157.170.170.117) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20; Mon, 27 Oct 2025 16:26:34 -0500 Received: from lelvem-mr06.itg.ti.com (10.180.75.8) by DLEE212.ent.ti.com (157.170.170.114) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20 via Frontend Transport; Mon, 27 Oct 2025 16:26:34 -0500 Received: from a0512632.dhcp.ti.com (a0512632.dhcp.ti.com [172.24.233.20]) by lelvem-mr06.itg.ti.com (8.18.1/8.18.1) with ESMTP id 59RLQP5l1301370; Mon, 27 Oct 2025 16:26:30 -0500 From: Swamil Jain To: , , , , , , , , , CC: , , , , , Subject: [PATCH v7 1/2] drm/tidss: Remove max_pclk_khz and min_pclk_khz from tidss display features Date: Tue, 28 Oct 2025 02:56:23 +0530 Message-ID: <20251027212624.359235-2-s-jain1@ti.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20251027212624.359235-1-s-jain1@ti.com> References: <20251027212624.359235-1-s-jain1@ti.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-C2ProcessedOrg: 333ef613-75bf-4e12-a4b1-8e3623f5dcea Content-Type: text/plain; charset="utf-8" From: Jayesh Choudhary The TIDSS hardware does not have independent maximum or minimum pixel clock limits for each video port. Instead, these limits are determined by the SoC's clock architecture. Previously, this constraint was modeled using the 'max_pclk_khz' and 'min_pclk_khz' fields in 'dispc_features', but this approach is static and does not account for the dynamic behavior of PLLs. This patch removes the 'max_pclk_khz' and 'min_pclk_khz' fields from 'dispc_features'. The correct way to check if a requested mode's pixel clock is supported is by using 'clk_round_rate()' in the 'mode_valid()' hook. If the best frequency match for the mode clock falls within the supported tolerance, it is approved. TIDSS supports a 5% pixel clock tolerance, which is now reflected in the validation logic. This change allows existing DSS-compatible drivers to be reused across SoCs that only differ in their pixel clock characteristics. The validation uses 'clk_round_rate()' for each mode, which may introduce additional delay (about 3.5 ms for 30 modes), but this is generally negligible. Users desiring faster validation may bypass these calls selectively, for example, checking only the highest resolution mode, as shown here[1]. [1]: https://lore.kernel.org/all/20250704094851.182131-3-j-choudhary@ti.com/ Tested-by: Michael Walle Reviewed-by: Devarsh Thakkar Signed-off-by: Jayesh Choudhary Signed-off-by: Swamil Jain --- drivers/gpu/drm/tidss/tidss_dispc.c | 85 ++++++++++------------------- drivers/gpu/drm/tidss/tidss_dispc.h | 3 - 2 files changed, 30 insertions(+), 58 deletions(-) diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/ti= dss_dispc.c index d0b191c470ca..07731b02490f 100644 --- a/drivers/gpu/drm/tidss/tidss_dispc.c +++ b/drivers/gpu/drm/tidss/tidss_dispc.c @@ -57,12 +57,6 @@ static const u16 tidss_k2g_common_regs[DISPC_COMMON_REG_= TABLE_LEN] =3D { }; =20 const struct dispc_features dispc_k2g_feats =3D { - .min_pclk_khz =3D 4375, - - .max_pclk_khz =3D { - [DISPC_VP_DPI] =3D 150000, - }, - /* * XXX According TRM the RGB input buffer width up to 2560 should * work on 3 taps, but in practice it only works up to 1280. @@ -145,11 +139,6 @@ static const u16 tidss_am65x_common_regs[DISPC_COMMON_= REG_TABLE_LEN] =3D { }; =20 const struct dispc_features dispc_am65x_feats =3D { - .max_pclk_khz =3D { - [DISPC_VP_DPI] =3D 165000, - [DISPC_VP_OLDI_AM65X] =3D 165000, - }, - .scaling =3D { .in_width_max_5tap_rgb =3D 1280, .in_width_max_3tap_rgb =3D 2560, @@ -245,11 +234,6 @@ static const u16 tidss_j721e_common_regs[DISPC_COMMON_= REG_TABLE_LEN] =3D { }; =20 const struct dispc_features dispc_j721e_feats =3D { - .max_pclk_khz =3D { - [DISPC_VP_DPI] =3D 170000, - [DISPC_VP_INTERNAL] =3D 600000, - }, - .scaling =3D { .in_width_max_5tap_rgb =3D 2048, .in_width_max_3tap_rgb =3D 4096, @@ -316,11 +300,6 @@ const struct dispc_features dispc_j721e_feats =3D { }; =20 const struct dispc_features dispc_am625_feats =3D { - .max_pclk_khz =3D { - [DISPC_VP_DPI] =3D 165000, - [DISPC_VP_INTERNAL] =3D 170000, - }, - .scaling =3D { .in_width_max_5tap_rgb =3D 1280, .in_width_max_3tap_rgb =3D 2560, @@ -377,15 +356,6 @@ const struct dispc_features dispc_am625_feats =3D { }; =20 const struct dispc_features dispc_am62a7_feats =3D { - /* - * if the code reaches dispc_mode_valid with VP1, - * it should return MODE_BAD. - */ - .max_pclk_khz =3D { - [DISPC_VP_TIED_OFF] =3D 0, - [DISPC_VP_DPI] =3D 165000, - }, - .scaling =3D { .in_width_max_5tap_rgb =3D 1280, .in_width_max_3tap_rgb =3D 2560, @@ -442,10 +412,6 @@ const struct dispc_features dispc_am62a7_feats =3D { }; =20 const struct dispc_features dispc_am62l_feats =3D { - .max_pclk_khz =3D { - [DISPC_VP_DPI] =3D 165000, - }, - .subrev =3D DISPC_AM62L, =20 .common =3D "common", @@ -1333,33 +1299,53 @@ static void dispc_vp_set_default_color(struct dispc= _device *dispc, DISPC_OVR_DEFAULT_COLOR2, (v >> 32) & 0xffff); } =20 +/* + * Calculate the percentage difference between the requested pixel clock r= ate + * and the effective rate resulting from calculating the clock divider val= ue. + */ +unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate) +{ + int r =3D rate / 100, rr =3D real_rate / 100; + + return (unsigned int)(abs(((rr - r) * 100) / r)); +} + +static int check_pixel_clock(struct dispc_device *dispc, + u32 hw_videoport, unsigned long clock) +{ + unsigned long round_clock; + + round_clock =3D clk_round_rate(dispc->vp_clk[hw_videoport], clock); + /* + * To keep the check consistent with dispc_vp_set_clk_rate(), we + * use the same 5% check here. + */ + if (dispc_pclk_diff(clock, round_clock) > 5) + return -EINVAL; + return 0; +} + enum drm_mode_status dispc_vp_mode_valid(struct dispc_device *dispc, u32 hw_videoport, const struct drm_display_mode *mode) { u32 hsw, hfp, hbp, vsw, vfp, vbp; enum dispc_vp_bus_type bus_type; - int max_pclk; =20 bus_type =3D dispc->feat->vp_bus_type[hw_videoport]; =20 - max_pclk =3D dispc->feat->max_pclk_khz[bus_type]; - - if (WARN_ON(max_pclk =3D=3D 0)) + if (WARN_ON(bus_type =3D=3D DISPC_VP_TIED_OFF)) return MODE_BAD; =20 - if (mode->clock < dispc->feat->min_pclk_khz) - return MODE_CLOCK_LOW; - - if (mode->clock > max_pclk) - return MODE_CLOCK_HIGH; - if (mode->hdisplay > 4096) return MODE_BAD; =20 if (mode->vdisplay > 4096) return MODE_BAD; =20 + if (check_pixel_clock(dispc, hw_videoport, mode->clock * 1000)) + return MODE_CLOCK_HIGH; + /* TODO: add interlace support */ if (mode->flags & DRM_MODE_FLAG_INTERLACE) return MODE_NO_INTERLACE; @@ -1423,17 +1409,6 @@ void dispc_vp_disable_clk(struct dispc_device *dispc= , u32 hw_videoport) clk_disable_unprepare(dispc->vp_clk[hw_videoport]); } =20 -/* - * Calculate the percentage difference between the requested pixel clock r= ate - * and the effective rate resulting from calculating the clock divider val= ue. - */ -unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate) -{ - int r =3D rate / 100, rr =3D real_rate / 100; - - return (unsigned int)(abs(((rr - r) * 100) / r)); -} - int dispc_vp_set_clk_rate(struct dispc_device *dispc, u32 hw_videoport, unsigned long rate) { diff --git a/drivers/gpu/drm/tidss/tidss_dispc.h b/drivers/gpu/drm/tidss/ti= dss_dispc.h index 60c1b400eb89..42279312dcc1 100644 --- a/drivers/gpu/drm/tidss/tidss_dispc.h +++ b/drivers/gpu/drm/tidss/tidss_dispc.h @@ -77,9 +77,6 @@ enum dispc_dss_subrevision { }; =20 struct dispc_features { - int min_pclk_khz; - int max_pclk_khz[DISPC_VP_MAX_BUS_TYPE]; - struct dispc_features_scaling scaling; =20 enum dispc_dss_subrevision subrev;