From nobody Fri Oct 3 11:15:09 2025 Received: from mail-wr1-f74.google.com (mail-wr1-f74.google.com [209.85.221.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EF8032E2DDD for ; Tue, 2 Sep 2025 07:39:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756798742; cv=none; b=Jo5X7O5bxCpApLtEFzS/fbPbo9K2M9xn42gQAKT8GIpmtvpmgc5JnNzg4g5j21i7jdukLpCN1mpscGZOQ6VDB/Mb3QRuI30TQo3EQfMcdIFBezc+BTdsvyHcBtOJRBi7qc3uXB/au8kaFqVuN5uKiSCJ94EwErXdFVCZEEcbClQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756798742; c=relaxed/simple; bh=qxr+CREui4pE7rWTCWj6E45p0I+6Etq/aCUmmlsx7ok=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=e1NOcAqhJaafHkPgOc8p12JC6obo67pf0pT/ySspRbRuW5EDeAm+9rXiKkOA1lGRHqRZnTA9Vau4TUYSap5+LQf2tn6wDn6CWBTHg9VyUI22yjSDdYZ0K3eTNFx42Xf7dw4+farmHCPQ7u5pzjtb3Nvq0TJCrOr06h7TEY+OnUs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--abarnas.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=RXmtI/tR; arc=none smtp.client-ip=209.85.221.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--abarnas.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="RXmtI/tR" Received: by mail-wr1-f74.google.com with SMTP id ffacd0b85a97d-3cef6debe96so2628478f8f.1 for ; Tue, 02 Sep 2025 00:39:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1756798739; x=1757403539; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=WE7v0z7TzjZvPVfK4+4Sp1UwAsOZUOttl1hBOuNjNnw=; b=RXmtI/tREvYorkHCf4d6iMF84kM8El9u92b3F9C3SL6kXV02xf81nAlAxqSSILTeSx MdGdC90i8eMYOs5s3/37tY7kEvGPzycBFPVHLTY8yrhXdjq4NIDZ6bOddHofdqC7WYq8 Y1jq6/MFRQ9Byja3MEK3G24cSuPERpq4Qhrvqd9liz0HXcg6pSmgNLIoBotmELb5lgxB aAsEkSScEiynhEpm1J3EII6hYzLNBYaPv2bKMwhi1fgopcUYQUqHHn+3IoIshcS1w/N8 tn1jxyOOkcCyW2dcKCXEPtgXkiXsATHgi2J4xcmNRiVLg+WvnZkGl5/vvWqZzb5lODwA RfCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756798739; x=1757403539; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=WE7v0z7TzjZvPVfK4+4Sp1UwAsOZUOttl1hBOuNjNnw=; b=g9rL0MfZqBA8c6UvroGYjYAIF14KnVut1sM8SD05bjk7RNBPCjdVm9A7LzfAxgLZ8v OW2dtpz4cchdqxCuchHr375cgSebJO9Fj2HgyRfyaJa5pD88LgmDk+eCUWBHk0YCCtQJ xSN7faFkbaGQfeZYQhtOu9mcpZ14ngmyOiL/Nxjhxx7eEFO4TvDEItfH5uagNWq1ZBIj CTg+9z8eVxmXYx9zja2ScFhcgpHDemwMswWOO6AfVK/9toSHk2e6AMeQqKH8HUBGD1HA ZNF7nqzRFAFQ5tGlVPMouT4/srpiWr3pm+vBq2zoPDo2eqNWjpIpduZZAuOMHkCEaNYU E43A== X-Forwarded-Encrypted: i=1; AJvYcCWGH195NKOoyk/0Q0/D+OZX2P5JIjkwMJ9To/v56ZyYSIVjANA+ubEw8k2HRXQ2cbFt6lw7wOhOEfuVDGw=@vger.kernel.org X-Gm-Message-State: AOJu0YzGmhRpzZEhwsBquFq6gOaZwGF2Y5hDAQ3/c/cSkpcdH0v63ebg 9y2Gqf7BUSzUFiFECpy3jABjEywwdXlL+a8fPAJlqkt6BL+dGejiaKOXFTPC2fhRm65K/UqJU7N 4u9iSuOrW4g== X-Google-Smtp-Source: AGHT+IGtOLqgwO0BX/6Sg5J5mhZ2KciPQ7kiO1dkbcPPy47bP+WENUmn6cded6JsjNVS6Jfarr14pjp35Rl5 X-Received: from wmsd13.prod.google.com ([2002:a05:600c:3acd:b0:459:dcf5:1b54]) (user=abarnas job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6000:2d82:b0:3d7:38a7:35dc with SMTP id ffacd0b85a97d-3d738a739a7mr3158803f8f.12.1756798739364; Tue, 02 Sep 2025 00:38:59 -0700 (PDT) Date: Tue, 2 Sep 2025 07:38:40 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.51.0.318.gd7df087d1a-goog Message-ID: <20250902073841.2338568-1-abarnas@google.com> Subject: [RFC] staging: media: atomisp: Simplyfy masking bit logic From: "=?UTF-8?q?Adrian=20Barna=C5=9B?=" To: Hans de Goede , Mauro Carvalho Chehab , Sakari Ailus , Andy Shevchenko , Greg Kroah-Hartman , Dan Carpenter , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-staging@lists.linux.dev Cc: "=?UTF-8?q?Adrian=20Barna=C5=9B?=" Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Simplified masking logic in pci/hive_isp_css_common/host/vmem.c. --- I have tested this change on whole range of *valid* inputs, and it gives the same results as before, but this function seems to be little counter-intuitive as far as start is a (bit index) but end is (bit index + 1). It is follow up to: https://lore.kernel.org/linux-staging/20250901091050.19= 35505-1-abarnas@google.com/ --- .../staging/media/atomisp/pci/hive_isp_css_common/host/vmem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/staging/media/atomisp/pci/hive_isp_css_common/host/vme= m.c b/drivers/staging/media/atomisp/pci/hive_isp_css_common/host/vmem.c index 722b684fbc37..9703e39b7497 100644 --- a/drivers/staging/media/atomisp/pci/hive_isp_css_common/host/vmem.c +++ b/drivers/staging/media/atomisp/pci/hive_isp_css_common/host/vmem.c @@ -22,14 +22,14 @@ typedef hive_uedge *hive_wide; static inline hive_uedge subword(hive_uedge w, unsigned int start, unsigned int end) { - return (w & (((1ULL << (end - 1)) - 1) << 1 | 1)) >> start; + return (w & __GENMASK_ULL(end-1, 0)) >> start; } =20 /* inverse subword bits move like this: MSB[xxxx____xxxx]LSB -> MSB[xxxx00= 00xxxx]LSB */ static inline hive_uedge inv_subword(hive_uedge w, unsigned int start, unsigned int end) { - return w & (~(((1ULL << (end - 1)) - 1) << 1 | 1) | ((1ULL << start) - 1)= ); + return w & (~__GENMASK_ULL(end-1, start)); } =20 #define uedge_bits (8 * sizeof(hive_uedge)) --=20 2.51.0.318.gd7df087d1a-goog