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-rw-r--r--arch/alpha/oprofile/op_model_ev4.c116
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diff --git a/arch/alpha/oprofile/op_model_ev4.c b/arch/alpha/oprofile/op_model_ev4.c
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+/**
+ * @file arch/alpha/oprofile/op_model_ev4.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author Richard Henderson <rth@twiddle.net>
+ */
+
+#include <linux/oprofile.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <asm/ptrace.h>
+#include <asm/system.h>
+
+#include "op_impl.h"
+
+
+/* Compute all of the registers in preparation for enabling profiling. */
+
+static void
+ev4_reg_setup(struct op_register_config *reg,
+ struct op_counter_config *ctr,
+ struct op_system_config *sys)
+{
+ unsigned long ctl = 0, count, hilo;
+
+ /* Select desired events. We've mapped the event numbers
+ such that they fit directly into the event selection fields.
+
+ Note that there is no "off" setting. In both cases we select
+ the EXTERNAL event source, hoping that it'll be the lowest
+ frequency, and set the frequency counter to LOW. The interrupts
+ for these "disabled" counter overflows are ignored by the
+ interrupt handler.
+
+ This is most irritating, because the hardware *can* enable and
+ disable the interrupts for these counters independently, but the
+ wrperfmon interface doesn't allow it. */
+
+ ctl |= (ctr[0].enabled ? ctr[0].event << 8 : 14 << 8);
+ ctl |= (ctr[1].enabled ? (ctr[1].event - 16) << 32 : 7ul << 32);
+
+ /* EV4 can not read or write its counter registers. The only
+ thing one can do at all is see if you overflow and get an
+ interrupt. We can set the width of the counters, to some
+ extent. Take the interrupt count selected by the user,
+ map it onto one of the possible values, and write it back. */
+
+ count = ctr[0].count;
+ if (count <= 4096)
+ count = 4096, hilo = 1;
+ else
+ count = 65536, hilo = 0;
+ ctr[0].count = count;
+ ctl |= (ctr[0].enabled && hilo) << 3;
+
+ count = ctr[1].count;
+ if (count <= 256)
+ count = 256, hilo = 1;
+ else
+ count = 4096, hilo = 0;
+ ctr[1].count = count;
+ ctl |= (ctr[1].enabled && hilo);
+
+ reg->mux_select = ctl;
+
+ /* Select performance monitoring options. */
+ /* ??? Need to come up with some mechanism to trace only
+ selected processes. EV4 does not have a mechanism to
+ select kernel or user mode only. For now, enable always. */
+ reg->proc_mode = 0;
+
+ /* Frequency is folded into mux_select for EV4. */
+ reg->freq = 0;
+
+ /* See above regarding no writes. */
+ reg->reset_values = 0;
+ reg->need_reset = 0;
+
+}
+
+/* Program all of the registers in preparation for enabling profiling. */
+
+static void
+ev4_cpu_setup(void *x)
+{
+ struct op_register_config *reg = x;
+
+ wrperfmon(2, reg->mux_select);
+ wrperfmon(3, reg->proc_mode);
+}
+
+static void
+ev4_handle_interrupt(unsigned long which, struct pt_regs *regs,
+ struct op_counter_config *ctr)
+{
+ /* EV4 can't properly disable counters individually.
+ Discard "disabled" events now. */
+ if (!ctr[which].enabled)
+ return;
+
+ /* Record the sample. */
+ oprofile_add_sample(regs, which);
+}
+
+
+struct op_axp_model op_model_ev4 = {
+ .reg_setup = ev4_reg_setup,
+ .cpu_setup = ev4_cpu_setup,
+ .reset_ctr = NULL,
+ .handle_interrupt = ev4_handle_interrupt,
+ .cpu_type = "alpha/ev4",
+ .num_counters = 2,
+ .can_set_proc_mode = 0,
+};