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[24.205.208.113]) by smtp.gmail.com with ESMTPSA id d15-20020a05622a15cf00b002de711a190bsm4066708qty.71.2022.03.04.13.04.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Mar 2022 13:04:05 -0800 (PST) From: trix@redhat.com To: jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, tvrtko.ursulin@linux.intel.com, airlied@linux.ie, daniel@ffwll.ch, nathan@kernel.org, ndesaulniers@google.com, ville.syrjala@linux.intel.com, matthew.d.roper@intel.com, lucas.demarchi@intel.com, airlied@redhat.com, imre.deak@intel.com Date: Fri, 4 Mar 2022 13:03:55 -0800 Message-Id: <20220304210355.608898-1-trix@redhat.com> X-Mailer: git-send-email 2.26.3 MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=trix@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Subject: [Intel-gfx] [PATCH] drm/i915: rework the error handling in *_dpll_params X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tom Rix , intel-gfx@lists.freedesktop.org, llvm@lists.linux.dev, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" From: Tom Rix Clang static analysis reports this issue intel_dpll.c:472:31: warning: The left operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] this_err = abs(clock.dot - target); ~~~~~~~~~ ^ In a loop clock.dot is set on successful call to i9xx_calc_dpll_params(). If the call fails, the later *is_valid() will use the previous loop's clock.dot. The *_dpll_params functions return an arithmetic statement with the clock.dot as the variable. Change the error handler to set clock.dot to 0 and jump to the return statement. Fixes: dccbea3b0704 ("drm/i915: calculate the port clock rate along with other PLL params") Signed-off-by: Tom Rix --- drivers/gpu/drm/i915/display/intel_dpll.c | 32 ++++++++++++++--------- 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dpll.c b/drivers/gpu/drm/i915/display/intel_dpll.c index 0ae37fdbf2a5b..ba7cada704288 100644 --- a/drivers/gpu/drm/i915/display/intel_dpll.c +++ b/drivers/gpu/drm/i915/display/intel_dpll.c @@ -309,11 +309,13 @@ int pnv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m2 + 2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot; } @@ -326,11 +328,13 @@ int i9xx_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = i9xx_dpll_compute_m(clock); clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n + 2 == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n + 2 == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n + 2); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot; } @@ -338,11 +342,13 @@ int vlv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m1 * clock->m2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot / 5; } @@ -350,12 +356,14 @@ int chv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m1 * clock->m2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(refclk, clock->m), clock->n << 22); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot / 5; } -- 2.26.3 From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 187D27C for ; Fri, 4 Mar 2022 21:04:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646427850; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=aB6Kk4CiP7ma9Bi5vpnU1x/1xVJ2+zGmFV9PkjhVvyE=; b=dB8AmjLbqsD2C0gDx/IC2EqzYkCOU0d2awYjnlTLcNFOST0j9J4tB62nOW7CcxVLQOUw4l 4j9LclIIfPOuP4IuFrorMvav5d3i/rq/qvF6+8mH5SXGbQkoG9Pg3Pv4Y4AcTrciv15+81 k9QkM/O96ND9ItA3Mt3BqstMVNWdZx4= Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-348-U4QYS8-ENDu3miFEJoP4SA-1; Fri, 04 Mar 2022 16:04:06 -0500 X-MC-Unique: U4QYS8-ENDu3miFEJoP4SA-1 Received: by mail-qk1-f198.google.com with SMTP id 7-20020a05620a048700b00648b76040f6so6543253qkr.9 for ; Fri, 04 Mar 2022 13:04:06 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=aB6Kk4CiP7ma9Bi5vpnU1x/1xVJ2+zGmFV9PkjhVvyE=; b=6abtWj0VEczRoqCbc5ihER1c43+964s1LhqT7T6kaX39rcJ2alOWe6df6lNy3neD60 L1N0fRB2c/KtthdstsQSXcoH1IpS6dj2bWpkEtlC5gju/3cmr4wZu77W0Y/b4OAyUgta Hh96sUD1CVTXfcD7/H24VbJVrxCMmqUb2fExnsjeTj5fgG7UhnTtJt/vxBB593WGyF+H naE/HndjUSv2fR4zaOrppzMtWhJCmSUAAQ79nh/3f2IugfNKyZGm7rRY+b5ckbb3UzSe aC6Da2RFePLCidwpBfIvOM+o+L3Nngdutk2egiqBRp5LVahpMSIENvXzxPe/pEs+yj+b 4DFw== X-Gm-Message-State: AOAM532wkXOuGSJT7N3lNBWfz4ZJqIZ4HuxIIXGqU5SJSjKWcWg+QaSe CLZg8D+OHO+eJwhHHLzty3h6efwmaj7/YhBf8V2DZPuTz3VhXAEbKMW+QbS9mEhkecmGuF5HY7X LZ2rEiEnyFtWixQ== X-Received: by 2002:ac8:7d0d:0:b0:2e0:4e16:d3e3 with SMTP id g13-20020ac87d0d000000b002e04e16d3e3mr596092qtb.140.1646427845905; Fri, 04 Mar 2022 13:04:05 -0800 (PST) X-Google-Smtp-Source: ABdhPJzl8+Ou2jNdvl2lw+bUe6/hKRdnkUMPqvw52WVW8CnKDZfAXFw9zzSyaFkAoX7LqTGuVUhhjg== X-Received: by 2002:ac8:7d0d:0:b0:2e0:4e16:d3e3 with SMTP id g13-20020ac87d0d000000b002e04e16d3e3mr596051qtb.140.1646427845459; Fri, 04 Mar 2022 13:04:05 -0800 (PST) Received: from localhost.localdomain.com (024-205-208-113.res.spectrum.com. [24.205.208.113]) by smtp.gmail.com with ESMTPSA id d15-20020a05622a15cf00b002de711a190bsm4066708qty.71.2022.03.04.13.04.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Mar 2022 13:04:05 -0800 (PST) From: trix@redhat.com To: jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, tvrtko.ursulin@linux.intel.com, airlied@linux.ie, daniel@ffwll.ch, nathan@kernel.org, ndesaulniers@google.com, ville.syrjala@linux.intel.com, matthew.d.roper@intel.com, lucas.demarchi@intel.com, airlied@redhat.com, imre.deak@intel.com Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Tom Rix Subject: [PATCH] drm/i915: rework the error handling in *_dpll_params Date: Fri, 4 Mar 2022 13:03:55 -0800 Message-Id: <20220304210355.608898-1-trix@redhat.com> X-Mailer: git-send-email 2.26.3 Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=trix@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" From: Tom Rix Clang static analysis reports this issue intel_dpll.c:472:31: warning: The left operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] this_err = abs(clock.dot - target); ~~~~~~~~~ ^ In a loop clock.dot is set on successful call to i9xx_calc_dpll_params(). If the call fails, the later *is_valid() will use the previous loop's clock.dot. The *_dpll_params functions return an arithmetic statement with the clock.dot as the variable. Change the error handler to set clock.dot to 0 and jump to the return statement. Fixes: dccbea3b0704 ("drm/i915: calculate the port clock rate along with other PLL params") Signed-off-by: Tom Rix --- drivers/gpu/drm/i915/display/intel_dpll.c | 32 ++++++++++++++--------- 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dpll.c b/drivers/gpu/drm/i915/display/intel_dpll.c index 0ae37fdbf2a5b..ba7cada704288 100644 --- a/drivers/gpu/drm/i915/display/intel_dpll.c +++ b/drivers/gpu/drm/i915/display/intel_dpll.c @@ -309,11 +309,13 @@ int pnv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m2 + 2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot; } @@ -326,11 +328,13 @@ int i9xx_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = i9xx_dpll_compute_m(clock); clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n + 2 == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n + 2 == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n + 2); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot; } @@ -338,11 +342,13 @@ int vlv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m1 * clock->m2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot / 5; } @@ -350,12 +356,14 @@ int chv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m1 * clock->m2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; 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[24.205.208.113]) by smtp.gmail.com with ESMTPSA id d15-20020a05622a15cf00b002de711a190bsm4066708qty.71.2022.03.04.13.04.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Mar 2022 13:04:05 -0800 (PST) From: trix@redhat.com To: jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, tvrtko.ursulin@linux.intel.com, airlied@linux.ie, daniel@ffwll.ch, nathan@kernel.org, ndesaulniers@google.com, ville.syrjala@linux.intel.com, matthew.d.roper@intel.com, lucas.demarchi@intel.com, airlied@redhat.com, imre.deak@intel.com Subject: [PATCH] drm/i915: rework the error handling in *_dpll_params Date: Fri, 4 Mar 2022 13:03:55 -0800 Message-Id: <20220304210355.608898-1-trix@redhat.com> X-Mailer: git-send-email 2.26.3 MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=trix@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tom Rix , intel-gfx@lists.freedesktop.org, llvm@lists.linux.dev, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Tom Rix Clang static analysis reports this issue intel_dpll.c:472:31: warning: The left operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] this_err = abs(clock.dot - target); ~~~~~~~~~ ^ In a loop clock.dot is set on successful call to i9xx_calc_dpll_params(). If the call fails, the later *is_valid() will use the previous loop's clock.dot. The *_dpll_params functions return an arithmetic statement with the clock.dot as the variable. Change the error handler to set clock.dot to 0 and jump to the return statement. Fixes: dccbea3b0704 ("drm/i915: calculate the port clock rate along with other PLL params") Signed-off-by: Tom Rix --- drivers/gpu/drm/i915/display/intel_dpll.c | 32 ++++++++++++++--------- 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dpll.c b/drivers/gpu/drm/i915/display/intel_dpll.c index 0ae37fdbf2a5b..ba7cada704288 100644 --- a/drivers/gpu/drm/i915/display/intel_dpll.c +++ b/drivers/gpu/drm/i915/display/intel_dpll.c @@ -309,11 +309,13 @@ int pnv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m2 + 2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot; } @@ -326,11 +328,13 @@ int i9xx_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = i9xx_dpll_compute_m(clock); clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n + 2 == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n + 2 == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n + 2); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot; } @@ -338,11 +342,13 @@ int vlv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m1 * clock->m2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot / 5; } @@ -350,12 +356,14 @@ int chv_calc_dpll_params(int refclk, struct dpll *clock) { clock->m = clock->m1 * clock->m2; clock->p = clock->p1 * clock->p2; - if (WARN_ON(clock->n == 0 || clock->p == 0)) - return 0; + if (WARN_ON(clock->n == 0 || clock->p == 0)) { + clock->dot = 0; + goto end; + } clock->vco = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(refclk, clock->m), clock->n << 22); clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p); - +end: return clock->dot / 5; } -- 2.26.3