Merge branch 'v3.19-next/cleanup-samsung' into v3.19-next/mach-exynos

5 files changed, 116 insertions, 96 deletions

diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile
index 775ee35cb277..bcefb5473ee4 100644
--- a/arch/arm/mach-exynos/Makefile
+++ b/arch/arm/mach-exynos/Makefile
@@ -17,9 +17,6 @@ obj-$(CONFIG_PM_GENERIC_DOMAINS) += pm_domains.o
 
 obj-$(CONFIG_SMP)               += platsmp.o headsmp.o
 
-obj-$(CONFIG_HOTPLUG_CPU)       += hotplug.o
-CFLAGS_hotplug.o                += -march=armv7-a
-
 plus_sec := $(call as-instr,.arch_extension sec,+sec)
 AFLAGS_exynos-smc.o             :=-Wa,-march=armv7-a$(plus_sec)
 AFLAGS_sleep.o                  :=-Wa,-march=armv7-a$(plus_sec)
diff --git a/arch/arm/mach-exynos/common.h b/arch/arm/mach-exynos/common.h
index ef95cb1cc00a..d4d09bc1e48c 100644
--- a/arch/arm/mach-exynos/common.h
+++ b/arch/arm/mach-exynos/common.h
@@ -139,8 +139,6 @@ extern void exynos_cpu_resume_ns(void);
 
 extern struct smp_operations exynos_smp_ops;
 
-extern void exynos_cpu_die(unsigned int cpu);
-
 /* PMU(Power Management Unit) support */
 
 #define PMU_TABLE_END   (-1U)
diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
deleted file mode 100644
index 4d86961a7957..000000000000
--- a/arch/arm/mach-exynos/hotplug.c
+++ /dev/null
@@ -1,91 +0,0 @@
-/*
- *  Cloned from linux/arch/arm/mach-realview/hotplug.c
- *
- *  Copyright (C) 2002 ARM Ltd.
- *  All Rights Reserved
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
-*/
-
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/smp.h>
-#include <linux/io.h>
-
-#include <asm/cacheflush.h>
-#include <asm/cp15.h>
-#include <asm/smp_plat.h>
-
-#include "common.h"
-#include "regs-pmu.h"
-
-static inline void cpu_leave_lowpower(void)
-{
-        unsigned int v;
-
-        asm volatile(
-        "mrc    p15, 0, %0, c1, c0, 0\n"
-        "       orr     %0, %0, %1\n"
-        "       mcr     p15, 0, %0, c1, c0, 0\n"
-        "       mrc     p15, 0, %0, c1, c0, 1\n"
-        "       orr     %0, %0, %2\n"
-        "       mcr     p15, 0, %0, c1, c0, 1\n"
-          : "=&r" (v)
-          : "Ir" (CR_C), "Ir" (0x40)
-          : "cc");
-}
-
-static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
-{
-        u32 mpidr = cpu_logical_map(cpu);
-        u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-
-        for (;;) {
-
-                /* Turn the CPU off on next WFI instruction. */
-                exynos_cpu_power_down(core_id);
-
-                wfi();
-
-                if (pen_release == core_id) {
-                        /*
-                         * OK, proper wakeup, we're done
-                         */
-                        break;
-                }
-
-                /*
-                 * Getting here, means that we have come out of WFI without
-                 * having been woken up - this shouldn't happen
-                 *
-                 * Just note it happening - when we're woken, we can report
-                 * its occurrence.
-                 */
-                (*spurious)++;
-        }
-}
-
-/*
- * platform-specific code to shutdown a CPU
- *
- * Called with IRQs disabled
- */
-void __ref exynos_cpu_die(unsigned int cpu)
-{
-        int spurious = 0;
-
-        v7_exit_coherency_flush(louis);
-
-        platform_do_lowpower(cpu, &spurious);
-
-        /*
-         * bring this CPU back into the world of cache
-         * coherency, and then restore interrupts
-         */
-        cpu_leave_lowpower();
-
-        if (spurious)
-                pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
-}
diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c
index 8543064dc445..adb36a8e8785 100644
--- a/arch/arm/mach-exynos/platsmp.c
+++ b/arch/arm/mach-exynos/platsmp.c
@@ -22,6 +22,7 @@
 #include <linux/of_address.h>
 
 #include <asm/cacheflush.h>
+#include <asm/cp15.h>
 #include <asm/smp_plat.h>
 #include <asm/smp_scu.h>
 #include <asm/firmware.h>
@@ -33,6 +34,88 @@
 
 extern void exynos4_secondary_startup(void);
 
+/*
+ * Set or clear the USE_DELAYED_RESET_ASSERTION option, set on Exynos4 SoCs
+ * during hot-(un)plugging CPUx.
+ *
+ * The feature can be cleared safely during first boot of secondary CPU.
+ *
+ * Exynos4 SoCs require setting USE_DELAYED_RESET_ASSERTION during powering
+ * down a CPU so the CPU idle clock down feature could properly detect global
+ * idle state when CPUx is off.
+ */
+static void exynos_set_delayed_reset_assertion(u32 core_id, bool enable)
+{
+        if (soc_is_exynos4()) {
+                unsigned int tmp;
+
+                tmp = pmu_raw_readl(EXYNOS_ARM_CORE_OPTION(core_id));
+                if (enable)
+                        tmp |= S5P_USE_DELAYED_RESET_ASSERTION;
+                else
+                        tmp &= ~(S5P_USE_DELAYED_RESET_ASSERTION);
+                pmu_raw_writel(tmp, EXYNOS_ARM_CORE_OPTION(core_id));
+        }
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static inline void cpu_leave_lowpower(u32 core_id)
+{
+        unsigned int v;
+
+        asm volatile(
+        "mrc    p15, 0, %0, c1, c0, 0\n"
+        "       orr     %0, %0, %1\n"
+        "       mcr     p15, 0, %0, c1, c0, 0\n"
+        "       mrc     p15, 0, %0, c1, c0, 1\n"
+        "       orr     %0, %0, %2\n"
+        "       mcr     p15, 0, %0, c1, c0, 1\n"
+          : "=&r" (v)
+          : "Ir" (CR_C), "Ir" (0x40)
+          : "cc");
+
+         exynos_set_delayed_reset_assertion(core_id, false);
+}
+
+static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
+{
+        u32 mpidr = cpu_logical_map(cpu);
+        u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+
+        for (;;) {
+
+                /* Turn the CPU off on next WFI instruction. */
+                exynos_cpu_power_down(core_id);
+
+                /*
+                 * Exynos4 SoCs require setting
+                 * USE_DELAYED_RESET_ASSERTION so the CPU idle
+                 * clock down feature could properly detect
+                 * global idle state when CPUx is off.
+                 */
+                exynos_set_delayed_reset_assertion(core_id, true);
+
+                wfi();
+
+                if (pen_release == core_id) {
+                        /*
+                         * OK, proper wakeup, we're done
+                         */
+                        break;
+                }
+
+                /*
+                 * Getting here, means that we have come out of WFI without
+                 * having been woken up - this shouldn't happen
+                 *
+                 * Just note it happening - when we're woken, we can report
+                 * its occurrence.
+                 */
+                (*spurious)++;
+        }
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
 /**
  * exynos_core_power_down : power down the specified cpu
  * @cpu : the cpu to power down
@@ -260,6 +343,9 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
                 udelay(10);
         }
 
+        /* No harm if this is called during first boot of secondary CPU */
+        exynos_set_delayed_reset_assertion(core_id, false);
+
         /*
          * now the secondary core is starting up let it run its
          * calibrations, then wait for it to finish
@@ -341,6 +427,33 @@ static void __init exynos_smp_prepare_cpus(unsigned int max_cpus)
         }
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+static void exynos_cpu_die(unsigned int cpu)
+{
+        int spurious = 0;
+        u32 mpidr = cpu_logical_map(cpu);
+        u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+
+        v7_exit_coherency_flush(louis);
+
+        platform_do_lowpower(cpu, &spurious);
+
+        /*
+         * bring this CPU back into the world of cache
+         * coherency, and then restore interrupts
+         */
+        cpu_leave_lowpower(core_id);
+
+        if (spurious)
+                pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
 struct smp_operations exynos_smp_ops __initdata = {
         .smp_init_cpus          = exynos_smp_init_cpus,
         .smp_prepare_cpus       = exynos_smp_prepare_cpus,
diff --git a/arch/arm/mach-exynos/regs-pmu.h b/arch/arm/mach-exynos/regs-pmu.h
index 4ea5e320c6d1..322f13277c3b 100644
--- a/arch/arm/mach-exynos/regs-pmu.h
+++ b/arch/arm/mach-exynos/regs-pmu.h
@@ -20,6 +20,7 @@
 
 #define S5P_USE_STANDBY_WFI0                    (1 << 16)
 #define S5P_USE_STANDBY_WFE0                    (1 << 24)
+#define S5P_USE_DELAYED_RESET_ASSERTION         BIT(12)
 
 #define EXYNOS_CORE_PO_RESET(n)                 ((1 << 4) << n)
 #define EXYNOS_WAKEUP_FROM_LOWPWR               (1 << 28)
@@ -108,6 +109,8 @@
                         (EXYNOS_ARM_CORE0_CONFIGURATION + (0x80 * (_nr)))
 #define EXYNOS_ARM_CORE_STATUS(_nr)             \
                         (EXYNOS_ARM_CORE_CONFIGURATION(_nr) + 0x4)
+#define EXYNOS_ARM_CORE_OPTION(_nr)             \
+                        (EXYNOS_ARM_CORE_CONFIGURATION(_nr) + 0x8)
 
 #define EXYNOS_ARM_COMMON_CONFIGURATION         0x2500
 #define EXYNOS_COMMON_CONFIGURATION(_nr)        \