From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e9.ny.us.ibm.com (e9.ny.us.ibm.com [32.97.182.139]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 2E3411A03C3 for ; Tue, 14 Oct 2014 18:53:15 +1100 (EST) Received: from /spool/local by e9.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 14 Oct 2014 03:53:13 -0400 Received: from b01cxnp23032.gho.pok.ibm.com (b01cxnp23032.gho.pok.ibm.com [9.57.198.27]) by d01dlp02.pok.ibm.com (Postfix) with ESMTP id 8B7EC6E803C for ; Tue, 14 Oct 2014 03:41:54 -0400 (EDT) Received: from d01av03.pok.ibm.com (d01av03.pok.ibm.com [9.56.224.217]) by b01cxnp23032.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id s9E7rArX51707916 for ; Tue, 14 Oct 2014 07:53:10 GMT Received: from d01av03.pok.ibm.com (localhost [127.0.0.1]) by d01av03.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s9E7r9iX017297 for ; Tue, 14 Oct 2014 03:53:10 -0400 Subject: [PATCH] cpuidle/powernv: Populate cpuidle state details by querying the device-tree From: Preeti U Murthy To: mpe@ellerman.id.au, rjw@rjwysocki.net, benh@kernel.crashing.org Date: Tue, 14 Oct 2014 13:23:00 +0530 Message-ID: <20141014075259.11810.50996.stgit@preeti.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Cc: shreyas@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-pm@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , We hard code the metrics relevant for cpuidle states in the kernel today. Instead pick them up from the device tree so that they remain relevant and updated for the system that the kernel is running on. Cc: linux-pm@vger.kernel.org Cc: Rafael J. Wysocki Cc: devicetree@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Signed-off-by: Preeti U. Murthy Signed-off-by: Shreyas B. Prabhu --- drivers/cpuidle/cpuidle-powernv.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index fa79392..b57681d 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -165,7 +165,8 @@ static int powernv_add_idle_states(void) int nr_idle_states = 1; /* Snooze */ int dt_idle_states; const __be32 *idle_state_flags; - u32 len_flags, flags; + const __be32 *idle_state_latency; + u32 len_flags, flags, latency_ns; int i; /* Currently we have snooze statically defined */ @@ -182,18 +183,32 @@ static int powernv_add_idle_states(void) return nr_idle_states; } + idle_state_latency = of_get_property(power_mgt, + "ibm,cpu-idle-state-latencies-ns", NULL); + if (!idle_state_latency) { + pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-latencies-ns\n"); + return nr_idle_states; + } + dt_idle_states = len_flags / sizeof(u32); for (i = 0; i < dt_idle_states; i++) { flags = be32_to_cpu(idle_state_flags[i]); + + /* Cpuidle accepts exit_latency in us and we estimate + * target residency to be 10x exit_latency + */ + latency_ns = be32_to_cpu(idle_state_latency[i]); if (flags & IDLE_USE_INST_NAP) { /* Add NAP state */ strcpy(powernv_states[nr_idle_states].name, "Nap"); strcpy(powernv_states[nr_idle_states].desc, "Nap"); powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIME_VALID; - powernv_states[nr_idle_states].exit_latency = 10; - powernv_states[nr_idle_states].target_residency = 100; + powernv_states[nr_idle_states].exit_latency = + ((unsigned int)latency_ns) / 1000; + powernv_states[nr_idle_states].target_residency = + ((unsigned int)latency_ns / 100); powernv_states[nr_idle_states].enter = &nap_loop; nr_idle_states++; } @@ -204,8 +219,10 @@ static int powernv_add_idle_states(void) strcpy(powernv_states[nr_idle_states].desc, "FastSleep"); powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TIMER_STOP; - powernv_states[nr_idle_states].exit_latency = 300; - powernv_states[nr_idle_states].target_residency = 1000000; + powernv_states[nr_idle_states].exit_latency = + ((unsigned int)latency_ns) / 1000; + powernv_states[nr_idle_states].target_residency = + ((unsigned int)latency_ns / 100); powernv_states[nr_idle_states].enter = &fastsleep_loop; nr_idle_states++; }