[PATCH 2/2] [i.MX6Q] Code cleanup & verification after fixing compilation error

Nitin Chaudhary nitinchaudhary1289 at gmail.com
Tue Aug 16 17:59:21 PDT 2016


Cleanup the code after fixing build error in Zhengyu Shen's perf mmdc
integrated driver. The error occured due to migration of CPU Hotplug
notifiers to a state machine based mechanism. Made the necessary cha-
nges into the code and tested the same on an i.MX6QP FSL Board. The
changes allow clean compilation and work fine as well. The results
are as follows:

root at RDU2:~ perf stat -a -e mmdc/busy-cycles/,mmdc/read-accesses/,mmdc/read-byte
s/,mmdc/total-cycles/,mmdc/write-accesses/,mmdc/write-bytes/ dd if=/dev/zero of=
/dev/null bs=1M count=5000
5000+0 records in
5000+0 records out
5242880000 bytes (5.2 GB) copied, 5.4982 s, 954 MB/s

 Performance counter stats for 'system wide':

        1597891298      mmdc/busy-cycles/
          28531959      mmdc/read-accesses/
            910.77 MB   mmdc/read-bytes/
        2917082184      mmdc/total-cycles/
          27965222      mmdc/write-accesses/
            894.91 MB   mmdc/write-bytes/

       5.527407668 seconds time elapsed

But still need to check why the automatic power saving mode is not getting
enabled in my board. Any help/guidance on the same will be appreciated.

Signed-off-by: Nitin Chaudhary <Nitin.Chaudhary at zii.aero>
---
 arch/arm/mach-imx/mmdc.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-imx/mmdc.c b/arch/arm/mach-imx/mmdc.c
index 95c222d..45790f5 100644
--- a/arch/arm/mach-imx/mmdc.c
+++ b/arch/arm/mach-imx/mmdc.c
@@ -204,9 +204,10 @@ static int mmdc_cpu_offline(unsigned int cpu)
 
 	perf_pmu_migrate_context(&pmu_ptr->pmu, cpu, target);
 	cpumask_set_cpu(target, &pmu_ptr->cpu);
-	/*	
-	if(pmu_ptr->irq)
-		WARN_ON(irq_set_affinity_hint(pmu_ptr->irq, &pmu_ptr->cpu) != 0);
+	/*
+	 * TODO: Need to check if we need it or not
+	 * if(pmu_ptr->irq)
+	 *	 WARN_ON(irq_set_affinity_hint(pmu_ptr->irq, &pmu_ptr->cpu) != 0);
 	*/
 	return 0;
 }
@@ -374,7 +375,12 @@ static int imx_mmdc_probe(struct platform_device *pdev)
 	if (unlikely(!timeout)) {
 		pr_warn("%s: failed to enable automatic power saving\n",
 			__func__);
-		//return -EBUSY;
+
+		/*
+		 * TODO: Need to check why Automatic Power saving is not
+		 * getting enabled successfully.
+		 * return -EBUSY;
+		 */
 	}
 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
 
-- 
2.7.4




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