From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2CC61606A326 for ; Fri, 6 Nov 2026 16:04:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=Cqyyhike Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 932B1112EEB; Fri, 6 Nov 2026 16:03:55 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) by gabe.freedesktop.org (Postfix) with ESMTPS id BF84A112EA1; Fri, 6 Nov 2026 16:03:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1793981029; x=1825517029; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=3e5zDchh9lbINzlMeKR/rKzqc1Y6C20PCpox8LpLzkA=; b=CqyyhikeYFnv5UtChlGn11mJPCyf9jL6ifQ2ExmKbVkAzcb2acjXYM2H 1N+oklkp/gPwVVxyWUDAInsElNHgoeTDOMUPmd04uGbuwKoWjimXK5KTe Ndv2Rsw2Igx6GsYcMcLAuabIPoIiw0bP3/E3im/gf6/oAJKfqHWowJQSZ Kx51tlfjtVtTeDKV1EodPlzA8pvfyRqo18pJcgR094U15iJ9dTWOsfdvk Q0TnZxj/I/QjnEOPj0vUadAt5ChJAKo2MdymMJM2CFAXMMBPJzJuQehiL ueCsLHvMYRVhmvW1BlxDXbaVJJNJQ7JQ/2FUFPQLHWFL+IjGS5oFWAe3W Q==; X-CSE-ConnectionGUID: SIYvZ/eJTlKSBqZzjgllPg== X-CSE-MsgGUID: 2V89lq/hTbWy8B/9sylQxg== X-IronPort-AV: E=McAfee;i="6800,10657,11958"; a="2835597" X-IronPort-AV: E=Sophos;i="6.27,197,1787036400"; d="scan'208";a="2835597" Received: from fmviesa011.fm.intel.com ([10.60.135.151]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Nov 2026 08:03:48 -0800 X-CSE-ConnectionGUID: T0y3ACk2RbKPPnM/AtDV9w== X-CSE-MsgGUID: fdhGLyo4Rh6er3c+ISDk6A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,197,1787036400"; d="scan'208";a="9074366" Received: from ettammin-mobl3.ger.corp.intel.com (HELO localhost) ([10.245.245.181]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Nov 2026 08:03:47 -0800 Date: Fri, 6 Nov 2026 18:03:43 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Jani Nikula Cc: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Subject: Re: [PATCH 3/9] drm/i915/de: Introduce mmio read/write templates Message-ID: References: <20261104221842.18799-1-ville.syrjala@linux.intel.com> <20261104221842.18799-4-ville.syrjala@linux.intel.com> <283ba9737e27cff4d70b7ee2ab3b0ec287d573de@intel.com> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <283ba9737e27cff4d70b7ee2ab3b0ec287d573de@intel.com> X-Patchwork-Hint: comment Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs Bertel Jungin Aukio 5, 02600 Espoo, Finland X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Intel-gfx" X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Fri, Nov 06, 2026 at 04:52:22PM +0200, Jani Nikula wrote: > On Thu, 05 Nov 2026, Ville Syrjala wrote: > > From: Ville Syrjälä > > > > In order to eliminate runtime platform check overhead from > > the mmio read/write functions, we'll need a good way to construct > > optimal variants for each platform. Do that in the form of > > __intel_de_{read,write}() that can be customized via (compile time > > constnt) mmio_flags. The compiler will eliminate all the stuff > > we don't want. > > Are the __always_inline required? Perhaps not in practice, don't think I actually checked the generated code without them. I put them there because I really want to force the compiler to notice that mmio_flags is a compile time constant and thus there is dead code to eliminate. Dunno if I want to rely on compiler inlining heuristics for that. > > Reviewed-by: Jani Nikula > > > > > For now there is nothing to eliminate but next we'll start > > moving more stuff in to make that possible. > > > > Signed-off-by: Ville Syrjälä > > --- > > drivers/gpu/drm/i915/display/intel_de.c | 26 +++++++++++++++++++++++-- > > 1 file changed, 24 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_de.c b/drivers/gpu/drm/i915/display/intel_de.c > > index 4f423a684ec2..cde2886fe2ca 100644 > > --- a/drivers/gpu/drm/i915/display/intel_de.c > > +++ b/drivers/gpu/drm/i915/display/intel_de.c > > @@ -163,16 +163,38 @@ u16 intel_de_read16(struct intel_display *display, intel_reg_t reg) > > return intel_uncore_read16(__to_uncore(display), reg); > > } > > > > +static __always_inline u32 > > +__intel_de_read(struct intel_display *display, intel_reg_t reg, > > + const unsigned int mmio_flags) > > +{ > > + u32 val; > > + > > + val = intel_uncore_read(__to_uncore(display), reg); > > + > > + return val; > > +} > > + > > +static __always_inline void > > +__intel_de_write(struct intel_display *display, intel_reg_t reg, u32 val, > > + const unsigned int mmio_flags) > > +{ > > + intel_uncore_write(__to_uncore(display), reg, val); > > +} > > + > > +#define I9XX_MMIO_FLAGS 0 > > + > > static u32 i9xx_mmio_read(struct intel_display *display, intel_reg_t reg) > > { > > - return intel_uncore_read(__to_uncore(display), reg); > > + return __intel_de_read(display, reg, I9XX_MMIO_FLAGS); > > } > > > > static void i9xx_mmio_write(struct intel_display *display, intel_reg_t reg, u32 val) > > { > > - intel_uncore_write(__to_uncore(display), reg, val); > > + __intel_de_write(display, reg, val, I9XX_MMIO_FLAGS); > > } > > > > +#undef I9XX_MMIO_FLAGS > > + > > static const struct intel_mmio_funcs i9xx_mmio_funcs = { > > .read = i9xx_mmio_read, > > .write = i9xx_mmio_write, > > -- > Jani Nikula, Intel -- Ville Syrjälä Intel