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-rw-r--r--arch/powerpc/kernel/pmc.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pmc.c b/arch/powerpc/kernel/pmc.c
new file mode 100644
index 00000000000..2d333cc8408
--- /dev/null
+++ b/arch/powerpc/kernel/pmc.c
@@ -0,0 +1,112 @@
+/*
+ * arch/powerpc/kernel/pmc.c
+ *
+ * Copyright (C) 2004 David Gibson, IBM Corporation.
+ * Includes code formerly from arch/ppc/kernel/perfmon.c:
+ * Author: Andy Fleming
+ * Copyright (c) 2004 Freescale Semiconductor, Inc
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+
+#include <asm/processor.h>
+#include <asm/pmc.h>
+
+#if defined(CONFIG_FSL_BOOKE) && !defined(CONFIG_E200)
+static void dummy_perf(struct pt_regs *regs)
+{
+ unsigned int pmgc0 = mfpmr(PMRN_PMGC0);
+
+ pmgc0 &= ~PMGC0_PMIE;
+ mtpmr(PMRN_PMGC0, pmgc0);
+}
+#elif defined(CONFIG_PPC64) || defined(CONFIG_6xx)
+
+#ifndef MMCR0_PMAO
+#define MMCR0_PMAO 0
+#endif
+
+/* Ensure exceptions are disabled */
+static void dummy_perf(struct pt_regs *regs)
+{
+ unsigned int mmcr0 = mfspr(SPRN_MMCR0);
+
+ mmcr0 &= ~(MMCR0_PMXE|MMCR0_PMAO);
+ mtspr(SPRN_MMCR0, mmcr0);
+}
+#else
+static void dummy_perf(struct pt_regs *regs)
+{
+}
+#endif
+
+static DEFINE_SPINLOCK(pmc_owner_lock);
+static void *pmc_owner_caller; /* mostly for debugging */
+perf_irq_t perf_irq = dummy_perf;
+
+int reserve_pmc_hardware(perf_irq_t new_perf_irq)
+{
+ int err = 0;
+
+ spin_lock(&pmc_owner_lock);
+
+ if (pmc_owner_caller) {
+ printk(KERN_WARNING "reserve_pmc_hardware: "
+ "PMC hardware busy (reserved by caller %p)\n",
+ pmc_owner_caller);
+ err = -EBUSY;
+ goto out;
+ }
+
+ pmc_owner_caller = __builtin_return_address(0);
+ perf_irq = new_perf_irq ? : dummy_perf;
+
+ out:
+ spin_unlock(&pmc_owner_lock);
+ return err;
+}
+EXPORT_SYMBOL_GPL(reserve_pmc_hardware);
+
+void release_pmc_hardware(void)
+{
+ spin_lock(&pmc_owner_lock);
+
+ WARN_ON(! pmc_owner_caller);
+
+ pmc_owner_caller = NULL;
+ perf_irq = dummy_perf;
+
+ spin_unlock(&pmc_owner_lock);
+}
+EXPORT_SYMBOL_GPL(release_pmc_hardware);
+
+#ifdef CONFIG_PPC64
+void power4_enable_pmcs(void)
+{
+ unsigned long hid0;
+
+ hid0 = mfspr(SPRN_HID0);
+ hid0 |= 1UL << (63 - 20);
+
+ /* POWER4 requires the following sequence */
+ asm volatile(
+ "sync\n"
+ "mtspr %1, %0\n"
+ "mfspr %0, %1\n"
+ "mfspr %0, %1\n"
+ "mfspr %0, %1\n"
+ "mfspr %0, %1\n"
+ "mfspr %0, %1\n"
+ "mfspr %0, %1\n"
+ "isync" : "=&r" (hid0) : "i" (SPRN_HID0), "0" (hid0):
+ "memory");
+}
+#endif /* CONFIG_PPC64 */