From mboxrd@z Thu Jan 1 00:00:00 1970 From: Santosh Shilimkar Subject: [pm-wip/cpufreq] [PATCH] OMAP2+: CPUfreq: update lpj with reference value to avoid progressive error. Date: Mon, 11 Jul 2011 23:10:04 +0530 Message-ID: <1310406004-5060-1-git-send-email-santosh.shilimkar@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: linux-omap@vger.kernel.org Cc: Kevin Hilman , Russell King , Santosh Shilimkar , linux-arm-kernel@lists.infradead.org List-Id: linux-omap@vger.kernel.org From: Russell King Adjust _both_ the per-cpu loops_per_jiffy and global lpj. Calibrate them with with reference to the initial values to avoid a progressively bigger and bigger error in the value over time. While at this, re-use the notifiers for UP/SMP since on UP machine or UP_ON_SMP policy->cpus mask would contain only the boot CPU. Signed-off-by: Santosh Shilimkar [santosh.shilimkar@ti.com: re-based against omap cpufreq upstream branch and fixed notifiers] Signed-off-by: Russell King Cc: Kevin Hilman --- Patch is outcome of below discussion. http://www.mail-archive.com/linux-omap@vger.kernel.org/msg51559.html arch/arm/mach-omap2/omap2plus-cpufreq.c | 50 ++++++++++++++++-------------- 1 files changed, 27 insertions(+), 23 deletions(-) diff --git a/arch/arm/mach-omap2/omap2plus-cpufreq.c b/arch/arm/mach-omap2/omap2plus-cpufreq.c index 1f3b2e1..de82e87 100644 --- a/arch/arm/mach-omap2/omap2plus-cpufreq.c +++ b/arch/arm/mach-omap2/omap2plus-cpufreq.c @@ -38,6 +38,16 @@ #include +#ifdef CONFIG_SMP +struct lpj_info { + unsigned long ref; + unsigned int freq; +}; + +static DEFINE_PER_CPU(struct lpj_info, lpj_ref); +static struct lpj_info global_lpj_ref; +#endif + static struct cpufreq_frequency_table *freq_table; static atomic_t freq_table_users = ATOMIC_INIT(0); static struct clk *mpu_clk; @@ -96,37 +106,18 @@ static int omap_target(struct cpufreq_policy *policy, if (freqs.old == freqs.new && policy->cur == freqs.new) return ret; - if (!is_smp()) { - cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); - goto set_freq; - } - /* notifiers */ for_each_cpu(i, policy->cpus) { freqs.cpu = i; cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); } -set_freq: #ifdef CONFIG_CPU_FREQ_DEBUG pr_info("cpufreq-omap: transition: %u --> %u\n", freqs.old, freqs.new); #endif ret = clk_set_rate(mpu_clk, freqs.new * 1000); - - /* - * Generic CPUFREQ driver jiffy update is under !SMP. So jiffies - * won't get updated when UP machine cpufreq build with - * CONFIG_SMP enabled. Below code is added only to manage that - * scenario - */ freqs.new = omap_getspeed(policy->cpu); - if (!is_smp()) { - loops_per_jiffy = - cpufreq_scale(loops_per_jiffy, freqs.old, freqs.new); - cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); - goto skip_lpj; - } #ifdef CONFIG_SMP /* @@ -134,10 +125,24 @@ set_freq: * cpufreq driver. So, update the per-CPU loops_per_jiffy value * on frequency transition. We need to update all dependent CPUs. */ - for_each_cpu(i, policy->cpus) + for_each_cpu(i, policy->cpus) { + struct lpj_info *lpj = &per_cpu(lpj_ref, i); + if (!lpj->freq) { + lpj->ref = per_cpu(cpu_data, i).loops_per_jiffy; + lpj->freq = freqs.old; + } + per_cpu(cpu_data, i).loops_per_jiffy = - cpufreq_scale(per_cpu(cpu_data, i).loops_per_jiffy, - freqs.old, freqs.new); + cpufreq_scale(lpj->ref, lpj->freq, freqs.new); + } + + /* And don't forget to adjust the global one */ + if (!global_lpj_ref.freq) { + global_lpj_ref.ref = loops_per_jiffy; + global_lpj_ref.freq = freqs.old; + } + loops_per_jiffy = cpufreq_scale(global_lpj_ref.ref, global_lpj_ref.freq, + freqs.new); #endif /* notifiers */ @@ -146,7 +151,6 @@ set_freq: cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); } -skip_lpj: return ret; } -- 1.6.0.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: santosh.shilimkar@ti.com (Santosh Shilimkar) Date: Mon, 11 Jul 2011 23:10:04 +0530 Subject: [pm-wip/cpufreq] [PATCH] OMAP2+: CPUfreq: update lpj with reference value to avoid progressive error. Message-ID: <1310406004-5060-1-git-send-email-santosh.shilimkar@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Russell King Adjust _both_ the per-cpu loops_per_jiffy and global lpj. Calibrate them with with reference to the initial values to avoid a progressively bigger and bigger error in the value over time. While at this, re-use the notifiers for UP/SMP since on UP machine or UP_ON_SMP policy->cpus mask would contain only the boot CPU. Signed-off-by: Santosh Shilimkar [santosh.shilimkar at ti.com: re-based against omap cpufreq upstream branch and fixed notifiers] Signed-off-by: Russell King Cc: Kevin Hilman --- Patch is outcome of below discussion. http://www.mail-archive.com/linux-omap at vger.kernel.org/msg51559.html arch/arm/mach-omap2/omap2plus-cpufreq.c | 50 ++++++++++++++++-------------- 1 files changed, 27 insertions(+), 23 deletions(-) diff --git a/arch/arm/mach-omap2/omap2plus-cpufreq.c b/arch/arm/mach-omap2/omap2plus-cpufreq.c index 1f3b2e1..de82e87 100644 --- a/arch/arm/mach-omap2/omap2plus-cpufreq.c +++ b/arch/arm/mach-omap2/omap2plus-cpufreq.c @@ -38,6 +38,16 @@ #include +#ifdef CONFIG_SMP +struct lpj_info { + unsigned long ref; + unsigned int freq; +}; + +static DEFINE_PER_CPU(struct lpj_info, lpj_ref); +static struct lpj_info global_lpj_ref; +#endif + static struct cpufreq_frequency_table *freq_table; static atomic_t freq_table_users = ATOMIC_INIT(0); static struct clk *mpu_clk; @@ -96,37 +106,18 @@ static int omap_target(struct cpufreq_policy *policy, if (freqs.old == freqs.new && policy->cur == freqs.new) return ret; - if (!is_smp()) { - cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); - goto set_freq; - } - /* notifiers */ for_each_cpu(i, policy->cpus) { freqs.cpu = i; cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); } -set_freq: #ifdef CONFIG_CPU_FREQ_DEBUG pr_info("cpufreq-omap: transition: %u --> %u\n", freqs.old, freqs.new); #endif ret = clk_set_rate(mpu_clk, freqs.new * 1000); - - /* - * Generic CPUFREQ driver jiffy update is under !SMP. So jiffies - * won't get updated when UP machine cpufreq build with - * CONFIG_SMP enabled. Below code is added only to manage that - * scenario - */ freqs.new = omap_getspeed(policy->cpu); - if (!is_smp()) { - loops_per_jiffy = - cpufreq_scale(loops_per_jiffy, freqs.old, freqs.new); - cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); - goto skip_lpj; - } #ifdef CONFIG_SMP /* @@ -134,10 +125,24 @@ set_freq: * cpufreq driver. So, update the per-CPU loops_per_jiffy value * on frequency transition. We need to update all dependent CPUs. */ - for_each_cpu(i, policy->cpus) + for_each_cpu(i, policy->cpus) { + struct lpj_info *lpj = &per_cpu(lpj_ref, i); + if (!lpj->freq) { + lpj->ref = per_cpu(cpu_data, i).loops_per_jiffy; + lpj->freq = freqs.old; + } + per_cpu(cpu_data, i).loops_per_jiffy = - cpufreq_scale(per_cpu(cpu_data, i).loops_per_jiffy, - freqs.old, freqs.new); + cpufreq_scale(lpj->ref, lpj->freq, freqs.new); + } + + /* And don't forget to adjust the global one */ + if (!global_lpj_ref.freq) { + global_lpj_ref.ref = loops_per_jiffy; + global_lpj_ref.freq = freqs.old; + } + loops_per_jiffy = cpufreq_scale(global_lpj_ref.ref, global_lpj_ref.freq, + freqs.new); #endif /* notifiers */ @@ -146,7 +151,6 @@ set_freq: cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); } -skip_lpj: return ret; } -- 1.6.0.4