Merge tag 'backport/v3.14.24-ltsi-rc1/sh-tmu-to-v3.18-rc1' into backport/v3.14.24...

[platform/adaptation/renesas_rcar/renesas_kernel.git] / arch / arm / mach-shmobile / timer.c

diff --git a/arch/arm/mach-shmobile/timer.c b/arch/arm/mach-shmobile/timer.c
index 62d7052..87c6be1 100644 (file)
--- a/arch/arm/mach-shmobile/timer.c
+++ b/arch/arm/mach-shmobile/timer.c
@@ -21,22 +21,59 @@
 #include <linux/platform_device.h>
 #include <linux/clocksource.h>
 #include <linux/delay.h>
+#include <linux/of_address.h>
 
-void __init shmobile_setup_delay(unsigned int max_cpu_core_mhz,
-                                unsigned int mult, unsigned int div)
+static void __init shmobile_setup_delay_hz(unsigned int max_cpu_core_hz,
+                                          unsigned int mult, unsigned int div)
 {
        /* calculate a worst-case loops-per-jiffy value
-        * based on maximum cpu core mhz setting and the
+        * based on maximum cpu core hz setting and the
         * __delay() implementation in arch/arm/lib/delay.S
         *
         * this will result in a longer delay than expected
         * when the cpu core runs on lower frequencies.
         */
 
-       unsigned int value = (1000000 * mult) / (HZ * div);
+       unsigned int value = HZ * div / mult;
 
        if (!preset_lpj)
-               preset_lpj = max_cpu_core_mhz * value;
+               preset_lpj = max_cpu_core_hz / value;
+}
+
+void __init shmobile_init_delay(void)
+{
+       struct device_node *np, *cpus;
+       bool is_a7_a8_a9 = false;
+       bool is_a15 = false;
+       u32 max_freq = 0;
+
+       cpus = of_find_node_by_path("/cpus");
+       if (!cpus)
+               return;
+
+       for_each_child_of_node(cpus, np) {
+               u32 freq;
+
+               if (!of_property_read_u32(np, "clock-frequency", &freq))
+                       max_freq = max(max_freq, freq);
+
+               if (of_device_is_compatible(np, "arm,cortex-a7") ||
+                   of_device_is_compatible(np, "arm,cortex-a8") ||
+                   of_device_is_compatible(np, "arm,cortex-a9"))
+                       is_a7_a8_a9 = true;
+               else if (of_device_is_compatible(np, "arm,cortex-a15"))
+                       is_a15 = true;
+       }
+
+       of_node_put(cpus);
+
+       if (!max_freq)
+               return;
+
+       if (is_a7_a8_a9)
+               shmobile_setup_delay_hz(max_freq, 1, 3);
+       else if (is_a15 && !IS_ENABLED(CONFIG_ARM_ARCH_TIMER))
+               shmobile_setup_delay_hz(max_freq, 2, 4);
 }
 
 static void __init shmobile_late_time_init(void)