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-rw-r--r--arch/powerpc/kernel/pmc.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pmc.c b/arch/powerpc/kernel/pmc.c
new file mode 100644
index 000000000..15414c8a2
--- /dev/null
+++ b/arch/powerpc/kernel/pmc.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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
+ */
+
+#include <linux/errno.h>
+#include <linux/bug.h>
+#include <linux/spinlock.h>
+#include <linux/export.h>
+
+#include <asm/processor.h>
+#include <asm/cputable.h>
+#include <asm/pmc.h>
+
+#ifndef MMCR0_PMAO
+#define MMCR0_PMAO 0
+#endif
+
+static void dummy_perf(struct pt_regs *regs)
+{
+#if defined(CONFIG_FSL_EMB_PERFMON)
+ mtpmr(PMRN_PMGC0, mfpmr(PMRN_PMGC0) & ~PMGC0_PMIE);
+#elif defined(CONFIG_PPC64) || defined(CONFIG_PPC_BOOK3S_32)
+ if (cur_cpu_spec->pmc_type == PPC_PMC_IBM)
+ mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~(MMCR0_PMXE|MMCR0_PMAO));
+#else
+ mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_PMXE);
+#endif
+}
+
+
+static DEFINE_RAW_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;
+
+ raw_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 ? new_perf_irq : dummy_perf;
+
+ out:
+ raw_spin_unlock(&pmc_owner_lock);
+ return err;
+}
+EXPORT_SYMBOL_GPL(reserve_pmc_hardware);
+
+void release_pmc_hardware(void)
+{
+ raw_spin_lock(&pmc_owner_lock);
+
+ WARN_ON(! pmc_owner_caller);
+
+ pmc_owner_caller = NULL;
+ perf_irq = dummy_perf;
+
+ raw_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 */