From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C85C93F39E4 for ; Fri, 18 Sep 2026 21:44:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789767884; cv=none; b=CfmZ47qSc8ZDfhuq3ABI1ys+s7leRcb5Y+DnGd8Ol31KdpDZgZeLkiNpgjtMETKW9gnuLNKKfP8WkTZoUwcd/0sDFJ926CAPFrN6Ru+sRbvGGra8BN9SsK3TetTSAJmOsuks8nuw2VW/RM+yMPGV0TeNul6X+xQjt0zl66lMlWs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789767884; c=relaxed/simple; bh=CDs76baU83eu9YSB4XXMekCzKsbmc98nJgjLbBum6Ho=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=DTu8ZkwNiQYk6UXweNb8LQbhUpSPf5qoaK1cNK4cyKfwK2WPRdkRUhlacoxuoijpFW8xVjth07WEpXba2K7m/FpRdUtHF46/rORckqO1wTjivWjWUXNEp9cqWFBD02t4GyO7GtdyXJBLncXiArXnsENbI/WHfOqHb9vuenKjB1Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oIGpJNV/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="oIGpJNV/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4458E1F000FF; Fri, 18 Sep 2026 21:44:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789767883; bh=55kCVMsbTazCq+1cTovBkH53ynwUrxyYXS6l9My9w+8=; h=From:To:Cc:Subject:Date; b=oIGpJNV/8v9VRDSUfiGhmPOivTFJ7a82xowvZKG7VE7y+q9wEmYhdwo+N+rsBgcWV KSOlyXokLvaKPxL7ByKdzU43kqvCnpWtBGenge9b0uh9Rzw9YP09wOcoeDgHRS7xQo qHNYIzLqwML0IXNXdtfjDF4KyqNV9gOX8JQ8CGfCPhQEzHiMqsotBpTt/lYQe1V8qp Y5eCcacCOtgkEHzfHfp2HPIuBqfzLW00YncwfsurvwSrEz4EYmY3pKOVsqY4BoMiF1 1SaR+1ZesHT1WuA/PhkgB4kY7874eMkuJ5xoWSCQWw+Qg4UY3alOIyUbnctUxkrAJF GTKOpSmK3zDgw== From: Thorsten Blum To: Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , "Ritesh Harjani (IBM)" , Shrikanth Hegde , Thorsten Blum Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: [PATCH] powerpc/sysfs: Use NSEC_PER_USEC for wait time conversions Date: Fri, 18 Sep 2026 23:43:41 +0200 Message-ID: <20260918214341.271211-3-blum@kernel.org> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2899; i=blum@kernel.org; h=from:subject; bh=CDs76baU83eu9YSB4XXMekCzKsbmc98nJgjLbBum6Ho=; b=owGbwMvMwCUWt7pQ4caZUj3G02pJDFlrN/QWHeTkUTYwKVg5/2u+zvzZKoUhZQavGrfOu/yH4 7HNyra3HaUsDGJcDLJiiiwPZv2Y4VtaU7nJJGInzBxWJpAhDFycAjCRnz8Y/qelxa5uK9ua0SF5 mn/WPvXWnD9rsxOWpUxYu+1e1ccfvsUM/5N3dgSeOxeVdi4/Rpol++KUFOk0/x9+GW13e598v3P /EiMA X-Developer-Key: i=blum@kernel.org; a=openpgp; fpr=1D60735E8AEF3BE473B69D84733678FD8DFEEAD4 Content-Transfer-Encoding: 8bit Replace the hard-coded conversion factor 1000 with NSEC_PER_USEC to clarify the units. Fix the comments describing the conversion from time-base ticks to nanoseconds. Also rename rem_us to rem_ticks since the remainder is measured in ticks. Signed-off-by: Thorsten Blum --- arch/powerpc/kernel/sysfs.c | 35 ++++++++++++++++++----------------- 1 file changed, 18 insertions(+), 17 deletions(-) diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c index 329c1690b5ed..2e3ef6df8837 100644 --- a/arch/powerpc/kernel/sysfs.c +++ b/arch/powerpc/kernel/sysfs.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -245,10 +246,10 @@ static unsigned int get_idle_ticks_bit(u64 ns) { u64 cycle; - if (ns >= 10000) - cycle = div_u64(ns + 500, 1000) * tb_ticks_per_usec; + if (ns >= 10 * NSEC_PER_USEC) + cycle = div_u64(ns + NSEC_PER_USEC / 2, NSEC_PER_USEC) * tb_ticks_per_usec; else - cycle = div_u64(ns * tb_ticks_per_usec, 1000); + cycle = div_u64(ns * tb_ticks_per_usec, NSEC_PER_USEC); if (!cycle) return 0; @@ -324,15 +325,15 @@ static ssize_t show_pw20_wait_time(struct device *dev, PWRMGTCR0_PW20_ENT_SHIFT; tb_cycle = (tb_cycle << (MAX_BIT - value + 1)); - /* convert ms to ns */ - if (tb_ticks_per_usec > 1000) { - time = div_u64(tb_cycle, tb_ticks_per_usec / 1000); + /* Convert time-base ticks to ns */ + if (tb_ticks_per_usec > NSEC_PER_USEC) { + time = div_u64(tb_cycle, tb_ticks_per_usec / NSEC_PER_USEC); } else { - u32 rem_us; + u32 rem_ticks; - time = div_u64_rem(tb_cycle, tb_ticks_per_usec, - &rem_us); - time = time * 1000 + rem_us * 1000 / tb_ticks_per_usec; + time = div_u64_rem(tb_cycle, tb_ticks_per_usec, &rem_ticks); + time *= NSEC_PER_USEC; + time += rem_ticks * NSEC_PER_USEC / tb_ticks_per_usec; } } else { time = pw20_wt; @@ -446,15 +447,15 @@ static ssize_t show_altivec_idle_wait_time(struct device *dev, PWRMGTCR0_AV_IDLE_CNT_SHIFT; tb_cycle = (tb_cycle << (MAX_BIT - value + 1)); - /* convert ms to ns */ - if (tb_ticks_per_usec > 1000) { - time = div_u64(tb_cycle, tb_ticks_per_usec / 1000); + /* Convert time-base ticks to ns */ + if (tb_ticks_per_usec > NSEC_PER_USEC) { + time = div_u64(tb_cycle, tb_ticks_per_usec / NSEC_PER_USEC); } else { - u32 rem_us; + u32 rem_ticks; - time = div_u64_rem(tb_cycle, tb_ticks_per_usec, - &rem_us); - time = time * 1000 + rem_us * 1000 / tb_ticks_per_usec; + time = div_u64_rem(tb_cycle, tb_ticks_per_usec, &rem_ticks); + time *= NSEC_PER_USEC; + time += rem_ticks * NSEC_PER_USEC / tb_ticks_per_usec; } } else { time = altivec_idle_wt;