Create a file "nest-pmu.c" to contain nest pmu related functions. Code
to detect nest pmu support and parser to collect per-chip reserved memory
region information from device tree (DT).
Detection mechanism is to look for specific property "ibm,ima-chip" in DT.
For Nest pmu, device tree will have two set of information.
1) Per-chip reserved memory region for nest pmu counter collection area.
2) Supported Nest PMUs and events
Device tree layout for the Nest PMU as follows.
/ -- DT root folder
|
-nest-ima -- Nest PMU folder
|
-ima-chip@<chip-id> -- Per-chip folder for reserved region information
|
-ibm,chip-id -- Chip id
-ibm,ima-chip
-reg -- HOMER PORE Nest Counter collection Address (RA)
-size -- size to map in kernel space
-Alink_BW -- Nest PMU folder
|
-Alink0 -- Nest PMU Alink Event file
-scale.Alink0.scale -- Event scale file
-unit.Alink0.unit -- Event unit file
-device_type -- "nest-ima-unit" marker
....
Subsequent patch will parse the next part of the DT to find various
Nest PMUs and their events.
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Anton Blanchard <an...@samba.org>
Cc: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khand...@linux.vnet.ibm.com>
Cc: Stephane Eranian <eran...@google.com>
Signed-off-by: Madhavan Srinivasan <ma...@linux.vnet.ibm.com>
---
arch/powerpc/perf/Makefile | 2 +-
arch/powerpc/perf/nest-pmu.c | 85 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 86 insertions(+), 1 deletion(-)
create mode 100644 arch/powerpc/perf/nest-pmu.c
diff --git a/arch/powerpc/perf/Makefile b/arch/powerpc/perf/Makefile
index f9c083a..6da656b 100644
--- a/arch/powerpc/perf/Makefile
+++ b/arch/powerpc/perf/Makefile
@@ -5,7 +5,7 @@ obj-$(CONFIG_PERF_EVENTS) += callchain.o
obj-$(CONFIG_PPC_PERF_CTRS) += core-book3s.o bhrb.o
obj64-$(CONFIG_PPC_PERF_CTRS) += power4-pmu.o ppc970-pmu.o power5-pmu.o \
power5+-pmu.o power6-pmu.o power7-pmu.o \
- power8-pmu.o
+ power8-pmu.o nest-pmu.o
obj32-$(CONFIG_PPC_PERF_CTRS) += mpc7450-pmu.o
obj-$(CONFIG_FSL_EMB_PERF_EVENT) += core-fsl-emb.o
diff --git a/arch/powerpc/perf/nest-pmu.c b/arch/powerpc/perf/nest-pmu.c
new file mode 100644
index 0000000..e7d45ed
--- /dev/null
+++ b/arch/powerpc/perf/nest-pmu.c
@@ -0,0 +1,85 @@
+/*
+ * Nest Performance Monitor counter support for POWER8 processors.
+ *
+ * Copyright (C) 2015 Madhavan Srinivasan, IBM Corporation.
+ *
+ * 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 "nest-pmu.h"
+
+static struct perchip_nest_info p8_nest_perchip_info[P8_NEST_MAX_CHIPS];
+
+static int nest_ima_dt_parser(void)
+{
+ const __be32 *gcid;
+ const __be64 *chip_ima_reg;
+ const __be64 *chip_ima_size;
+ struct device_node *dev;
+ struct perchip_nest_info *p8ni;
+ int idx;
+
+ /*
+ * "nest-ima" folder contains two things,
+ * a) per-chip reserved memory region for Nest PMU Counter data
+ * b) Support Nest PMU units and their event files
+ */
+ for_each_node_with_property(dev, "ibm,ima-chip") {
+ gcid = of_get_property(dev, "ibm,chip-id", NULL);
+ chip_ima_reg = of_get_property(dev, "reg", NULL);
+ chip_ima_size = of_get_property(dev, "size", NULL);
+
+ if ((!gcid) || (!chip_ima_reg) || (!chip_ima_size)) {
+ pr_err("Nest_PMU: device %s missing property\n",
+ dev->full_name);
+ return -ENODEV;
+ }
+
+ /* chip id to save reserve memory region */
+ idx = (uint32_t)be32_to_cpup(gcid);
+
+ /*
+ * Using a local variable to make it compact and
+ * easier to read
+ */
+ p8ni = &p8_nest_perchip_info[idx];
+ p8ni->pbase = be64_to_cpup(chip_ima_reg);
+ p8ni->size = be64_to_cpup(chip_ima_size);
+ p8ni->vbase = (uint64_t) phys_to_virt(p8ni->pbase);
+ }
+
+ return 0;
+}
+
+static int __init nest_pmu_init(void)
+{
+ int ret = -ENODEV;
+
+ /*
+ * Lets do this only if we are hypervisor
+ */
+ if (!cur_cpu_spec->oprofile_cpu_type ||
+ !(strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power8") == 0) ||
+ !cpu_has_feature(CPU_FTR_HVMODE))
+ return ret;
+
+ /*
+ * Nest PMU information is grouped under "nest-ima" node
+ * of the top-level device-tree directory. Detect Nest PMU
+ * by the "ibm,ima-chip" property.
+ */
+ if (!of_find_node_with_property(NULL, "ibm,ima-chip"))
+ return ret;
+
+ /*
+ * Parse device-tree for Nest PMU information
+ */
+ ret = nest_ima_dt_parser();
+ if (ret)
+ return ret;
+
+ return 0;
+}
+device_initcall(nest_pmu_init);
--
1.9.1
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