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Message-Id: <1405091188-31754-1-git-send-email-pawel.moll@arm.com>
Date: Fri, 11 Jul 2014 16:06:28 +0100
From: Pawel Moll <pawel.moll@....com>
To: Rob Herring <robh+dt@...nel.org>,
Mark Rutland <mark.rutland@....com>,
Ian Campbell <ijc+devicetree@...lion.org.uk>,
Kumar Gala <galak@...eaurora.org>,
Grant Likely <grant.likely@...aro.org>,
Arnd Bergmann <arnd@...db.de>,
Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
Stephane Eranian <eranian@...gle.com>,
Jiri Olsa <jolsa@...hat.com>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Ingo Molnar <mingo@...nel.org>
Cc: linux-kernel@...r.kernel.org, devicetree@...r.kernel.org,
linux-arm-kernel@...ts.infradead.org,
Pawel Moll <pawel.moll@....com>
Subject: [PATCH v2] bus: ARM CCN PMU driver
Driver providing perf backend for ARM Cache Coherent Network
interconnect. Supports counting all hardware events and crosspoint
watchpoints.
Currently works with CCN-504 only, although there should be
no changes required for CCN-508 (just impossible to test it now).
Signed-off-by: Pawel Moll <pawel.moll@....com>
---
Changes from v1:
- removed unwanted hunks in Kconfig and Makefile (stupid rebasing
mistake)
Documentation/arm/CCN.txt | 52 +
Documentation/devicetree/bindings/arm/ccn.txt | 21 +
drivers/bus/Kconfig | 7 +
drivers/bus/Makefile | 4 +-
drivers/bus/arm-ccn.c | 1390 +++++++++++++++++++++++++
5 files changed, 1473 insertions(+), 1 deletion(-)
create mode 100644 Documentation/arm/CCN.txt
create mode 100644 Documentation/devicetree/bindings/arm/ccn.txt
create mode 100644 drivers/bus/arm-ccn.c
diff --git a/Documentation/arm/CCN.txt b/Documentation/arm/CCN.txt
new file mode 100644
index 0000000..0632b3a
--- /dev/null
+++ b/Documentation/arm/CCN.txt
@@ -0,0 +1,52 @@
+ARM Cache Coherent Network
+==========================
+
+CCN-504 is a ring-bus interconnect consisting of 11 crosspoints
+(XPs), with each crosspoint supporting up to two device ports,
+so nodes (devices) 0 and 1 are connected to crosspoint 0,
+nodes 2 and 3 to crosspoint 1 etc.
+
+PMU (perf) driver
+-----------------
+
+The CCN driver registers a perf PMU driver, which provides
+description of available events and configuration options
+in sysfs, see /sys/bus/event_source/devices/ccn*.
+
+The "format" directory describes format of the config, config1
+and config2 fields of the perf_event_attr structure. The "events"
+directory provides configuration templates for all documented
+events, that can be used with perf tool. For example "xp_valid_flit"
+is an equivalent of "type=0x8,event=0x4". Other parameters must be
+explicitly specified. For events originating from device, "node"
+defines its index. All crosspoint events require "xp" (index),
+"port" (device port number) and "vc" (virtual channel ID) and
+"dir" (direction). Watchpoints (special "event" value 0xfe) also
+require comparator values ("cmp_l" and "cmp_h") and "mask", being
+index of the comparator mask.
+
+Masks are defined separately from the event description
+(due to limited number of the config values) in the "cmp_mask"
+directory, with first 8 configurable by user and additional
+4 hardcoded for the most frequent use cases.
+
+Cycle counter is described by a "type" value 0xff and does
+not require any other settings.
+
+Example of perf tool use:
+
+/ # perf list | grep ccn
+ ccn/cycles/ [Kernel PMU event]
+<...>
+ ccn/xp_valid_flit/ [Kernel PMU event]
+<...>
+
+/ # perf stat -C 0 -e ccn/cycles/,ccn/xp_valid_flit,xp=1,port=0,vc=1,dir=1/ \
+ sleep 1
+
+The driver does not support sampling, therefore "perf record" will
+not work. Also notice that only single cpu is being selected
+("-C 0") - this is because perf framework does not support
+"non-CPU related" counters (yet?) so system-wide session ("-a")
+would try (and in most cases fail) to set up the same event
+per each CPU.
diff --git a/Documentation/devicetree/bindings/arm/ccn.txt b/Documentation/devicetree/bindings/arm/ccn.txt
new file mode 100644
index 0000000..b100d38
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/ccn.txt
@@ -0,0 +1,21 @@
+* ARM CCN (Cache Coherent Network)
+
+Required properties:
+
+- compatible: (standard compatible string) should be one of:
+ "arm,ccn-504"
+ "arm,ccn-508"
+
+- reg: (standard registers property) physical address and size
+ (16MB) of the configuration registers block
+
+- interrupts: (standard interrupt property) single interrupt
+ generated by the control block
+
+Example:
+
+ ccn@...000000000 {
+ compatible = "arm,ccn-504";
+ reg = <0x20 0x00000000 0 0x1000000>;
+ interrupts = <0 181 4>;
+ };
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 1f37d98..5c0c276 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -50,6 +50,13 @@ config ARM_CCI
Driver supporting the CCI cache coherent interconnect for ARM
platforms.
+config ARM_CCN
+ bool "ARM CCN driver support"
+ depends on ARM || ARM64
+ help
+ PMU (perf) driver supporting the ARM CCN (Cache Coherent Network)
+ interconnect.
+
config VEXPRESS_CONFIG
bool "Versatile Express configuration bus"
default y if ARCH_VEXPRESS
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index 6a4ea7e..2973c18 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -9,7 +9,9 @@ obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o
# Interconnect bus driver for OMAP SoCs.
obj-$(CONFIG_OMAP_INTERCONNECT) += omap_l3_smx.o omap_l3_noc.o
-# CCI cache coherent interconnect for ARM platforms
+
+# Interconnect bus drivers for ARM platforms
obj-$(CONFIG_ARM_CCI) += arm-cci.o
+obj-$(CONFIG_ARM_CCN) += arm-ccn.o
obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o
diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c
new file mode 100644
index 0000000..4f86bbb
--- /dev/null
+++ b/drivers/bus/arm-ccn.c
@@ -0,0 +1,1390 @@
+/*
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2014 ARM Limited
+ */
+
+#include <linux/ctype.h>
+#include <linux/hrtimer.h>
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define CCN_NUM_XP_PORTS 2
+#define CCN_NUM_VCS 4
+#define CCN_NUM_REGIONS 256
+#define CCN_REGION_SIZE 0x10000
+
+#define CCN_ALL_OLY_ID 0xff00
+#define CCN_ALL_OLY_ID__OLY_ID__SHIFT 0
+#define CCN_ALL_OLY_ID__OLY_ID__MASK 0x1f
+#define CCN_ALL_OLY_ID__NODE_ID__SHIFT 8
+#define CCN_ALL_OLY_ID__NODE_ID__MASK 0x3f
+
+#define CCN_MN_ERRINT_STATUS 0x0008
+#define CCN_MN_ERRINT_STATUS__INTREQ__DESSERT 0x11
+#define CCN_MN_ERRINT_STATUS__ALL_ERRORS__ENABLE 0x02
+#define CCN_MN_ERRINT_STATUS__ALL_ERRORS__DISABLED 0x20
+#define CCN_MN_ERRINT_STATUS__ALL_ERRORS__DISABLE 0x22
+#define CCN_MN_ERRINT_STATUS__CORRECTED_ERRORS_ENABLE 0x04
+#define CCN_MN_ERRINT_STATUS__CORRECTED_ERRORS_DISABLED 0x40
+#define CCN_MN_ERRINT_STATUS__CORRECTED_ERRORS_DISABLE 0x44
+#define CCN_MN_ERRINT_STATUS__PMU_EVENTS__ENABLE 0x08
+#define CCN_MN_ERRINT_STATUS__PMU_EVENTS__DISABLED 0x80
+#define CCN_MN_ERRINT_STATUS__PMU_EVENTS__DISABLE 0x88
+#define CCN_MN_OLY_COMP_LIST_63_0 0x01e0
+#define CCN_MN_ERR_SIG_VAL_63_0 0x0300
+#define CCN_MN_ERR_SIG_VAL_63_0__DT (1 << 1)
+
+#define CCN_DT_ACTIVE_DSM 0x0000
+#define CCN_DT_ACTIVE_DSM__DSM_ID__SHIFT(n) ((n) * 8)
+#define CCN_DT_ACTIVE_DSM__DSM_ID__MASK 0xff
+#define CCN_DT_CTL 0x0028
+#define CCN_DT_CTL__DT_EN (1 << 0)
+#define CCN_DT_PMEVCNT(n) (0x0100 + (n) * 0x8)
+#define CCN_DT_PMCCNTR 0x0140
+#define CCN_DT_PMCCNTRSR 0x0190
+#define CCN_DT_PMOVSR 0x0198
+#define CCN_DT_PMOVSR_CLR 0x01a0
+#define CCN_DT_PMCR 0x01a8
+#define CCN_DT_PMCR__OVFL_INTR_EN (1 << 6)
+#define CCN_DT_PMCR__PMU_EN (1 << 0)
+#define CCN_DT_PMSR 0x01b0
+#define CCN_DT_PMSR_REQ 0x01b8
+#define CCN_DT_PMSR_CLR 0x01c0
+
+#define CCN_HNF_PMU_EVENT_SEL 0x0600
+#define CCN_HNF_PMU_EVENT_SEL__ID__SHIFT(n) ((n) * 4)
+#define CCN_HNF_PMU_EVENT_SEL__ID__MASK 0xf
+
+#define CCN_XP_DT_CONFIG 0x0300
+#define CCN_XP_DT_CONFIG__DT_CFG__SHIFT(n) ((n) * 4)
+#define CCN_XP_DT_CONFIG__DT_CFG__MASK 0xf
+#define CCN_XP_DT_CONFIG__DT_CFG__PASS_THROUGH 0x0
+#define CCN_XP_DT_CONFIG__DT_CFG__WATCHPOINT_0_OR_1 0x1
+#define CCN_XP_DT_CONFIG__DT_CFG__WATCHPOINT(n) (0x2 + (n))
+#define CCN_XP_DT_CONFIG__DT_CFG__XP_PMU_EVENT(n) (0x4 + (n))
+#define CCN_XP_DT_CONFIG__DT_CFG__DEVICE_PMU_EVENT(d, n) (0x8 + (d) * 4 + (n))
+#define CCN_XP_DT_INTERFACE_SEL 0x0308
+#define CCN_XP_DT_INTERFACE_SEL__DT_IO_SEL__SHIFT(n) (0 + (n) * 8)
+#define CCN_XP_DT_INTERFACE_SEL__DT_IO_SEL__MASK 0x1
+#define CCN_XP_DT_INTERFACE_SEL__DT_DEV_SEL__SHIFT(n) (1 + (n) * 8)
+#define CCN_XP_DT_INTERFACE_SEL__DT_DEV_SEL__MASK 0x1
+#define CCN_XP_DT_INTERFACE_SEL__DT_VC_SEL__SHIFT(n) (2 + (n) * 8)
+#define CCN_XP_DT_INTERFACE_SEL__DT_VC_SEL__MASK 0x3
+#define CCN_XP_DT_CMP_VAL_L(n) (0x0310 + (n) * 0x40)
+#define CCN_XP_DT_CMP_VAL_H(n) (0x0318 + (n) * 0x40)
+#define CCN_XP_DT_CMP_MASK_L(n) (0x0320 + (n) * 0x40)
+#define CCN_XP_DT_CMP_MASK_H(n) (0x0328 + (n) * 0x40)
+#define CCN_XP_DT_CONTROL 0x0370
+#define CCN_XP_DT_CONTROL__DT_ENABLE (1 << 0)
+#define CCN_XP_DT_CONTROL__WP_ARM_SEL__SHIFT(n) (12 + (n) * 4)
+#define CCN_XP_DT_CONTROL__WP_ARM_SEL__MASK 0xf
+#define CCN_XP_DT_CONTROL__WP_ARM_SEL__ALWAYS 0xf
+#define CCN_XP_PMU_EVENT_SEL 0x0600
+#define CCN_XP_PMU_EVENT_SEL__ID__SHIFT(n) ((n) * 7)
+#define CCN_XP_PMU_EVENT_SEL__ID__MASK 0x3f
+
+#define CCN_SBAS_PMU_EVENT_SEL 0x0600
+#define CCN_SBAS_PMU_EVENT_SEL__ID__SHIFT(n) ((n) * 4)
+#define CCN_SBAS_PMU_EVENT_SEL__ID__MASK 0xf
+
+#define CCN_RNI_PMU_EVENT_SEL 0x0600
+#define CCN_RNI_PMU_EVENT_SEL__ID__SHIFT(n) ((n) * 4)
+#define CCN_RNI_PMU_EVENT_SEL__ID__MASK 0xf
+
+#define CCN_TYPE_MN 0x01
+#define CCN_TYPE_DT 0x02
+#define CCN_TYPE_HNF 0x04
+#define CCN_TYPE_HNI 0x05
+#define CCN_TYPE_XP 0x08
+#define CCN_TYPE_SBSX 0x0c
+#define CCN_TYPE_SBAS 0x10
+#define CCN_TYPE_RNI_1P 0x14
+#define CCN_TYPE_RNI_2P 0x15
+#define CCN_TYPE_RNI_3P 0x16
+#define CCN_TYPE_RND_1P 0x18 /* RN-D = RN-I + DVM */
+#define CCN_TYPE_RND_2P 0x19
+#define CCN_TYPE_RND_3P 0x1a
+#define CCN_TYPE_CYCLES 0xff /* Pseudotype */
+
+#define CCN_EVENT_WATCHPOINT 0xfe /* Pseudoevent */
+
+#define CCN_NUM_PMU_EVENTS 4
+#define CCN_NUM_XP_WATCHPOINTS 2 /* See DT.dbg_id.num_watchpoints */
+#define CCN_NUM_PMU_EVENT_COUNTERS 8 /* See DT.dbg_id.num_pmucntr */
+#define CCN_IDX_PMU_CYCLE_COUNTER CCN_NUM_PMU_EVENT_COUNTERS
+
+#define CCN_NUM_PREDEFINED_MASKS 4
+#define CCN_IDX_MASK_ANY (CCN_NUM_PMU_EVENT_COUNTERS + 0)
+#define CCN_IDX_MASK_EXACT (CCN_NUM_PMU_EVENT_COUNTERS + 1)
+#define CCN_IDX_MASK_ORDER (CCN_NUM_PMU_EVENT_COUNTERS + 2)
+#define CCN_IDX_MASK_OPCODE (CCN_NUM_PMU_EVENT_COUNTERS + 3)
+
+struct arm_ccn_component {
+ void __iomem *base;
+ u32 type;
+
+ DECLARE_BITMAP(pmu_events_mask, CCN_NUM_PMU_EVENTS);
+ union {
+ struct {
+ DECLARE_BITMAP(dt_cmp_mask, CCN_NUM_XP_WATCHPOINTS);
+ } xp;
+ };
+};
+
+#define pmu_to_arm_ccn(_pmu) container_of(container_of(_pmu, \
+ struct arm_ccn_dt, pmu), struct arm_ccn, dt)
+
+struct arm_ccn_dt {
+ int id;
+ void __iomem *base;
+
+ spinlock_t config_lock;
+
+ DECLARE_BITMAP(pmu_counters_mask, CCN_NUM_PMU_EVENT_COUNTERS + 1);
+ struct {
+ struct arm_ccn_component *source;
+ struct perf_event *event;
+ } pmu_counters[CCN_NUM_PMU_EVENT_COUNTERS + 1];
+
+ struct {
+ u64 l, h;
+ } cmp_mask[CCN_NUM_PMU_EVENT_COUNTERS + CCN_NUM_PREDEFINED_MASKS];
+
+ struct hrtimer hrtimer;
+
+ struct pmu pmu;
+};
+
+struct arm_ccn {
+ struct device *dev;
+ void __iomem *base;
+ unsigned irq_used:1;
+ unsigned sbas_present:1;
+ unsigned sbsx_present:1;
+
+ int num_nodes;
+ struct arm_ccn_component *node;
+
+ int num_xps;
+ struct arm_ccn_component *xp;
+
+ struct arm_ccn_dt dt;
+};
+
+
+static int arm_ccn_node_to_xp(int node)
+{
+ return node / CCN_NUM_XP_PORTS;
+}
+
+static int arm_ccn_node_to_xp_port(int node)
+{
+ return node % CCN_NUM_XP_PORTS;
+}
+
+
+/*
+ * Bit shifts and masks in these defines must be kept in sync with
+ * arm_ccn_pmu_config_set() and CCN_FORMAT_ATTRs below!
+ */
+#define CCN_CONFIG_NODE(_config) (((_config) >> 0) & 0xff)
+#define CCN_CONFIG_XP(_config) (((_config) >> 0) & 0xff)
+#define CCN_CONFIG_TYPE(_config) (((_config) >> 8) & 0xff)
+#define CCN_CONFIG_EVENT(_config) (((_config) >> 16) & 0xff)
+#define CCN_CONFIG_PORT(_config) (((_config) >> 24) & 0x3)
+#define CCN_CONFIG_VC(_config) (((_config) >> 26) & 0x7)
+#define CCN_CONFIG_DIR(_config) (((_config) >> 29) & 0x1)
+#define CCN_CONFIG_MASK(_config) (((_config) >> 30) & 0xf)
+
+static void arm_ccn_pmu_config_set(u64 *config, u32 node_xp, u32 type, u32 port)
+{
+ *config &= ~((0xff << 0) | (0xff << 8) | (0xff << 24));
+ *config |= (node_xp << 0) | (type << 8) | (port << 24);
+}
+
+static ssize_t arm_ccn_pmu_format_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dev_ext_attribute *ea = container_of(attr,
+ struct dev_ext_attribute, attr);
+
+ return snprintf(buf, PAGE_SIZE, "%s\n", (char *)ea->var);
+}
+
+#define CCN_FORMAT_ATTR(_name, _config) \
+ struct dev_ext_attribute arm_ccn_pmu_format_attr_##_name = \
+ { __ATTR(_name, S_IRUGO, arm_ccn_pmu_format_show, \
+ NULL), _config }
+
+static CCN_FORMAT_ATTR(node, "config:0-7");
+static CCN_FORMAT_ATTR(xp, "config:0-7");
+static CCN_FORMAT_ATTR(type, "config:8-15");
+static CCN_FORMAT_ATTR(event, "config:16-23");
+static CCN_FORMAT_ATTR(port, "config:24-25");
+static CCN_FORMAT_ATTR(vc, "config:26-28");
+static CCN_FORMAT_ATTR(dir, "config:29-29");
+static CCN_FORMAT_ATTR(mask, "config:30-33");
+static CCN_FORMAT_ATTR(cmp_l, "config1:0-62");
+static CCN_FORMAT_ATTR(cmp_h, "config2:0-59");
+
+static struct attribute *arm_ccn_pmu_format_attrs[] = {
+ &arm_ccn_pmu_format_attr_node.attr.attr,
+ &arm_ccn_pmu_format_attr_xp.attr.attr,
+ &arm_ccn_pmu_format_attr_type.attr.attr,
+ &arm_ccn_pmu_format_attr_event.attr.attr,
+ &arm_ccn_pmu_format_attr_port.attr.attr,
+ &arm_ccn_pmu_format_attr_vc.attr.attr,
+ &arm_ccn_pmu_format_attr_dir.attr.attr,
+ &arm_ccn_pmu_format_attr_mask.attr.attr,
+ &arm_ccn_pmu_format_attr_cmp_l.attr.attr,
+ &arm_ccn_pmu_format_attr_cmp_h.attr.attr,
+ NULL
+};
+
+static struct attribute_group arm_ccn_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = arm_ccn_pmu_format_attrs,
+};
+
+
+struct arm_ccn_pmu_event {
+ struct device_attribute attr;
+ u32 type;
+ u32 event;
+ int num_ports;
+ int num_vcs;
+ const char *def;
+ int mask;
+};
+
+#define CCN_EVENT_ATTR(_name) \
+ __ATTR(_name, S_IRUGO, arm_ccn_pmu_event_show, NULL)
+
+/*
+ * Events defined in TRM for MN, HN-I and SBSX are actually watchpoints set on
+ * their ports in XP they are connected to. For the sake of usability they are
+ * explicitly defined here (and translated into a relevant watchpoint in
+ * arm_ccn_pmu_event_init()) so the user can easily request them without deep
+ * knowledge of the flit format.
+ */
+
+#define CCN_EVENT_MN(_name, _def, _mask) { .attr = CCN_EVENT_ATTR(mn_##_name), \
+ .type = CCN_TYPE_MN, .event = CCN_EVENT_WATCHPOINT, \
+ .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, \
+ .def = _def, .mask = _mask, }
+
+#define CCN_EVENT_HNI(_name, _def, _mask) { \
+ .attr = CCN_EVENT_ATTR(hni_##_name), .type = CCN_TYPE_HNI, \
+ .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
+ .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
+
+#define CCN_EVENT_SBSX(_name, _def, _mask) { \
+ .attr = CCN_EVENT_ATTR(sbsx_##_name), .type = CCN_TYPE_SBSX, \
+ .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
+ .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
+
+#define CCN_EVENT_HNF(_name, _event) { .attr = CCN_EVENT_ATTR(hnf_##_name), \
+ .type = CCN_TYPE_HNF, .event = _event, }
+
+#define CCN_EVENT_XP(_name, _event) { .attr = CCN_EVENT_ATTR(xp_##_name), \
+ .type = CCN_TYPE_XP, .event = _event, \
+ .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, }
+
+/*
+ * RN-I & RN-D (RN-D = RN-I + DVM) nodes have different type ID depending
+ * on configuration. One of them is picked to represent the whole group,
+ * as they all share the same event types.
+ */
+#define CCN_EVENT_RNI(_name, _event) { .attr = CCN_EVENT_ATTR(rni_##_name), \
+ .type = CCN_TYPE_RNI_3P, .event = _event, }
+
+#define CCN_EVENT_SBAS(_name, _event) { .attr = CCN_EVENT_ATTR(sbas_##_name), \
+ .type = CCN_TYPE_SBAS, .event = _event, }
+
+#define CCN_EVENT_CYCLES(_name) { .attr = CCN_EVENT_ATTR(_name), \
+ .type = CCN_TYPE_CYCLES }
+
+
+static ssize_t arm_ccn_pmu_event_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct arm_ccn_pmu_event *event = container_of(attr,
+ struct arm_ccn_pmu_event, attr);
+ ssize_t res;
+
+ res = snprintf(buf, PAGE_SIZE, "type=0x%x", event->type);
+ if (event->event)
+ res += snprintf(buf + res, PAGE_SIZE - res, ",event=0x%x",
+ event->event);
+ if (event->def)
+ res += snprintf(buf + res, PAGE_SIZE - res, ",%s",
+ event->def);
+ if (event->mask)
+ res += snprintf(buf + res, PAGE_SIZE - res, ",mask=0x%x",
+ event->mask);
+ res += snprintf(buf + res, PAGE_SIZE - res, "\n");
+
+ return res;
+}
+
+static umode_t arm_ccn_pmu_events_is_visible(struct kobject *kobj,
+ struct attribute *attr, int index)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct arm_ccn *ccn = pmu_to_arm_ccn(dev_get_drvdata(dev));
+ struct device_attribute *dev_attr = container_of(attr,
+ struct device_attribute, attr);
+ struct arm_ccn_pmu_event *event = container_of(dev_attr,
+ struct arm_ccn_pmu_event, attr);
+
+ if (event->type == CCN_TYPE_SBAS && !ccn->sbas_present)
+ return 0;
+ if (event->type == CCN_TYPE_SBSX && !ccn->sbsx_present)
+ return 0;
+
+ return attr->mode;
+}
+
+static struct arm_ccn_pmu_event arm_ccn_pmu_events[] = {
+ CCN_EVENT_MN(eobarrier, "dir=0,vc=0,cmp_h=0x1c00", CCN_IDX_MASK_OPCODE),
+ CCN_EVENT_MN(ecbarrier, "dir=0,vc=0,cmp_h=0x1e00", CCN_IDX_MASK_OPCODE),
+ CCN_EVENT_MN(dvmop, "dir=0,vc=0,cmp_h=0x2800", CCN_IDX_MASK_OPCODE),
+ CCN_EVENT_HNI(txdatflits, "dir=1,vc=3", CCN_IDX_MASK_ANY),
+ CCN_EVENT_HNI(rxdatflits, "dir=0,vc=3", CCN_IDX_MASK_ANY),
+ CCN_EVENT_HNI(txreqflits, "dir=1,vc=0", CCN_IDX_MASK_ANY),
+ CCN_EVENT_HNI(rxreqflits, "dir=0,vc=0", CCN_IDX_MASK_ANY),
+ CCN_EVENT_HNI(rxreqflits_order, "dir=0,vc=0,cmp_h=0x8000",
+ CCN_IDX_MASK_ORDER),
+ CCN_EVENT_SBSX(txdatflits, "dir=1,vc=3", CCN_IDX_MASK_ANY),
+ CCN_EVENT_SBSX(rxdatflits, "dir=0,vc=3", CCN_IDX_MASK_ANY),
+ CCN_EVENT_SBSX(txreqflits, "dir=1,vc=0", CCN_IDX_MASK_ANY),
+ CCN_EVENT_SBSX(rxreqflits, "dir=0,vc=0", CCN_IDX_MASK_ANY),
+ CCN_EVENT_SBSX(rxreqflits_order, "dir=0,vc=0,cmp_h=0x8000",
+ CCN_IDX_MASK_ORDER),
+ CCN_EVENT_HNF(cache_miss, 0x1),
+ CCN_EVENT_HNF(l3_sf_cache_access, 0x02),
+ CCN_EVENT_HNF(cache_fill, 0x3),
+ CCN_EVENT_HNF(pocq_retry, 0x4),
+ CCN_EVENT_HNF(pocq_reqs_recvd, 0x5),
+ CCN_EVENT_HNF(sf_hit, 0x6),
+ CCN_EVENT_HNF(sf_evictions, 0x7),
+ CCN_EVENT_HNF(snoops_sent, 0x8),
+ CCN_EVENT_HNF(snoops_broadcast, 0x9),
+ CCN_EVENT_HNF(l3_eviction, 0xa),
+ CCN_EVENT_HNF(l3_fill_invalid_way, 0xb),
+ CCN_EVENT_HNF(mc_retries, 0xc),
+ CCN_EVENT_HNF(mc_reqs, 0xd),
+ CCN_EVENT_HNF(qos_hh_retry, 0xe),
+ CCN_EVENT_RNI(rdata_beats_p0, 0x1),
+ CCN_EVENT_RNI(rdata_beats_p1, 0x2),
+ CCN_EVENT_RNI(rdata_beats_p2, 0x3),
+ CCN_EVENT_RNI(rxdat_flits, 0x4),
+ CCN_EVENT_RNI(txdat_flits, 0x5),
+ CCN_EVENT_RNI(txreq_flits, 0x6),
+ CCN_EVENT_RNI(txreq_flits_retried, 0x7),
+ CCN_EVENT_RNI(rrt_full, 0x8),
+ CCN_EVENT_RNI(wrt_full, 0x9),
+ CCN_EVENT_RNI(txreq_flits_replayed, 0xa),
+ CCN_EVENT_XP(upload_starvation, 0x1),
+ CCN_EVENT_XP(download_starvation, 0x2),
+ CCN_EVENT_XP(respin, 0x3),
+ CCN_EVENT_XP(valid_flit, 0x4),
+ CCN_EVENT_XP(watchpoint, CCN_EVENT_WATCHPOINT),
+ CCN_EVENT_SBAS(rdata_beats_p0, 0x1),
+ CCN_EVENT_SBAS(rxdat_flits, 0x4),
+ CCN_EVENT_SBAS(txdat_flits, 0x5),
+ CCN_EVENT_SBAS(txreq_flits, 0x6),
+ CCN_EVENT_SBAS(txreq_flits_retried, 0x7),
+ CCN_EVENT_SBAS(rrt_full, 0x8),
+ CCN_EVENT_SBAS(wrt_full, 0x9),
+ CCN_EVENT_SBAS(txreq_flits_replayed, 0xa),
+ CCN_EVENT_CYCLES(cycles),
+};
+
+/* Populated in arm_ccn_init() */
+static struct attribute
+ *arm_ccn_pmu_events_attrs[ARRAY_SIZE(arm_ccn_pmu_events) + 1];
+
+static struct attribute_group arm_ccn_pmu_events_attr_group = {
+ .name = "events",
+ .is_visible = arm_ccn_pmu_events_is_visible,
+ .attrs = arm_ccn_pmu_events_attrs,
+};
+
+
+static u64 *arm_ccn_pmu_get_cmp_mask(struct arm_ccn *ccn, const char *name)
+{
+ unsigned long i;
+
+ if (WARN_ON(!name || !name[0] || !isxdigit(name[0]) || !name[1]))
+ return NULL;
+ i = isdigit(name[0]) ? name[0] - '0' : 0xa + tolower(name[0]) - 'a';
+
+ switch (name[1]) {
+ case 'l':
+ return &ccn->dt.cmp_mask[i].l;
+ case 'h':
+ return &ccn->dt.cmp_mask[i].h;
+ default:
+ return NULL;
+ }
+}
+
+static ssize_t arm_ccn_pmu_cmp_mask_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(dev_get_drvdata(dev));
+ u64 *mask = arm_ccn_pmu_get_cmp_mask(ccn, attr->attr.name);
+
+ return mask ? snprintf(buf, PAGE_SIZE, "0x%016llx\n", *mask) : -EINVAL;
+}
+
+static ssize_t arm_ccn_pmu_cmp_mask_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(dev_get_drvdata(dev));
+ u64 *mask = arm_ccn_pmu_get_cmp_mask(ccn, attr->attr.name);
+ int err = -EINVAL;
+
+ if (mask)
+ err = kstrtoull(buf, 0, mask);
+
+ return err ? err : count;
+}
+
+#define CCN_CMP_MASK_ATTR(_name) \
+ struct device_attribute arm_ccn_pmu_cmp_mask_attr_##_name = \
+ __ATTR(_name, S_IRUGO | S_IWUSR, \
+ arm_ccn_pmu_cmp_mask_show, arm_ccn_pmu_cmp_mask_store)
+
+#define CCN_CMP_MASK_ATTR_RO(_name) \
+ struct device_attribute arm_ccn_pmu_cmp_mask_attr_##_name = \
+ __ATTR(_name, S_IRUGO, arm_ccn_pmu_cmp_mask_show, NULL)
+
+static CCN_CMP_MASK_ATTR(0l);
+static CCN_CMP_MASK_ATTR(0h);
+static CCN_CMP_MASK_ATTR(1l);
+static CCN_CMP_MASK_ATTR(1h);
+static CCN_CMP_MASK_ATTR(2l);
+static CCN_CMP_MASK_ATTR(2h);
+static CCN_CMP_MASK_ATTR(3l);
+static CCN_CMP_MASK_ATTR(3h);
+static CCN_CMP_MASK_ATTR(4l);
+static CCN_CMP_MASK_ATTR(4h);
+static CCN_CMP_MASK_ATTR(5l);
+static CCN_CMP_MASK_ATTR(5h);
+static CCN_CMP_MASK_ATTR(6l);
+static CCN_CMP_MASK_ATTR(6h);
+static CCN_CMP_MASK_ATTR(7l);
+static CCN_CMP_MASK_ATTR(7h);
+static CCN_CMP_MASK_ATTR_RO(8l);
+static CCN_CMP_MASK_ATTR_RO(8h);
+static CCN_CMP_MASK_ATTR_RO(9l);
+static CCN_CMP_MASK_ATTR_RO(9h);
+static CCN_CMP_MASK_ATTR_RO(al);
+static CCN_CMP_MASK_ATTR_RO(ah);
+static CCN_CMP_MASK_ATTR_RO(bl);
+static CCN_CMP_MASK_ATTR_RO(bh);
+
+static struct attribute *arm_ccn_pmu_cmp_mask_attrs[] = {
+ &arm_ccn_pmu_cmp_mask_attr_0l.attr, &arm_ccn_pmu_cmp_mask_attr_0h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_1l.attr, &arm_ccn_pmu_cmp_mask_attr_1h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_2l.attr, &arm_ccn_pmu_cmp_mask_attr_2h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_3l.attr, &arm_ccn_pmu_cmp_mask_attr_3h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_4l.attr, &arm_ccn_pmu_cmp_mask_attr_4h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_5l.attr, &arm_ccn_pmu_cmp_mask_attr_5h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_6l.attr, &arm_ccn_pmu_cmp_mask_attr_6h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_7l.attr, &arm_ccn_pmu_cmp_mask_attr_7h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_8l.attr, &arm_ccn_pmu_cmp_mask_attr_8h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_9l.attr, &arm_ccn_pmu_cmp_mask_attr_9h.attr,
+ &arm_ccn_pmu_cmp_mask_attr_al.attr, &arm_ccn_pmu_cmp_mask_attr_ah.attr,
+ &arm_ccn_pmu_cmp_mask_attr_bl.attr, &arm_ccn_pmu_cmp_mask_attr_bh.attr,
+ NULL
+};
+
+static struct attribute_group arm_ccn_pmu_cmp_mask_attr_group = {
+ .name = "cmp_mask",
+ .attrs = arm_ccn_pmu_cmp_mask_attrs,
+};
+
+
+/*
+ * Default poll period is 10ms, which is way over the top anyway,
+ * as in the worst case scenario (an event every cycle), with 1GHz
+ * clocked bus, the smallest, 32 bit counter will overflow in
+ * more than 4s.
+ */
+static unsigned int arm_ccn_pmu_poll_period_us = 10000;
+module_param_named(pmu_poll_period_us, arm_ccn_pmu_poll_period_us, uint,
+ S_IRUGO | S_IWUSR);
+
+static ktime_t arm_ccn_pmu_timer_period(void)
+{
+ return ns_to_ktime((u64)arm_ccn_pmu_poll_period_us * 1000);
+}
+
+
+static const struct attribute_group *arm_ccn_pmu_attr_groups[] = {
+ &arm_ccn_pmu_events_attr_group,
+ &arm_ccn_pmu_format_attr_group,
+ &arm_ccn_pmu_cmp_mask_attr_group,
+ NULL
+};
+
+
+static int arm_ccn_pmu_alloc_bit(unsigned long *bitmap, unsigned long size)
+{
+ int bit;
+
+ do {
+ bit = find_first_zero_bit(bitmap, size);
+ if (bit >= size)
+ return -EAGAIN;
+ } while (test_and_set_bit(bit, bitmap));
+
+ return bit;
+}
+
+/* All RN-I and RN-D nodes have identical PMUs */
+static int arm_ccn_pmu_type_eq(u32 a, u32 b)
+{
+ if (a == b)
+ return 1;
+
+ switch (a) {
+ case CCN_TYPE_RNI_1P:
+ case CCN_TYPE_RNI_2P:
+ case CCN_TYPE_RNI_3P:
+ case CCN_TYPE_RND_1P:
+ case CCN_TYPE_RND_2P:
+ case CCN_TYPE_RND_3P:
+ switch (b) {
+ case CCN_TYPE_RNI_1P:
+ case CCN_TYPE_RNI_2P:
+ case CCN_TYPE_RNI_3P:
+ case CCN_TYPE_RND_1P:
+ case CCN_TYPE_RND_2P:
+ case CCN_TYPE_RND_3P:
+ return 1;
+ }
+ break;
+ }
+
+ return 0;
+}
+
+static int arm_ccn_pmu_event_init(struct perf_event *event)
+{
+ struct arm_ccn *ccn;
+ struct hw_perf_event *hw = &event->hw;
+ u32 node_xp, type, event_id;
+ int valid;
+ struct arm_ccn_component *source;
+ int i;
+
+ if (event->attr.type != event->pmu->type)
+ return -ENOENT;
+
+ ccn = pmu_to_arm_ccn(event->pmu);
+
+ if (hw->sample_period) {
+ dev_warn(ccn->dev, "Sampling not supported!\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (has_branch_stack(event) || event->attr.exclude_user ||
+ event->attr.exclude_kernel || event->attr.exclude_hv ||
+ event->attr.exclude_idle) {
+ dev_warn(ccn->dev, "Can't exclude execution levels!\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (event->cpu < 0) {
+ dev_warn(ccn->dev, "Can't provide per-task data!\n");
+ return -EOPNOTSUPP;
+ }
+
+ node_xp = CCN_CONFIG_NODE(event->attr.config);
+ type = CCN_CONFIG_TYPE(event->attr.config);
+ event_id = CCN_CONFIG_EVENT(event->attr.config);
+
+ /* Validate node/xp vs topology */
+ switch (type) {
+ case CCN_TYPE_XP:
+ if (node_xp >= ccn->num_xps) {
+ dev_warn(ccn->dev, "Invalid XP ID %d!\n", node_xp);
+ return -EINVAL;
+ }
+ break;
+ case CCN_TYPE_CYCLES:
+ break;
+ default:
+ if (node_xp >= ccn->num_nodes) {
+ dev_warn(ccn->dev, "Invalid node ID %d!\n", node_xp);
+ return -EINVAL;
+ }
+ if (!arm_ccn_pmu_type_eq(type, ccn->node[node_xp].type)) {
+ dev_warn(ccn->dev, "Invalid type 0x%x for node %d!\n",
+ type, node_xp);
+ return -EINVAL;
+ }
+ break;
+ }
+
+ /* Validate event ID vs available for the type */
+ for (i = 0, valid = 0; i < ARRAY_SIZE(arm_ccn_pmu_events) && !valid;
+ i++) {
+ struct arm_ccn_pmu_event *e = &arm_ccn_pmu_events[i];
+ u32 port = CCN_CONFIG_PORT(event->attr.config);
+ u32 vc = CCN_CONFIG_VC(event->attr.config);
+
+ if (!arm_ccn_pmu_type_eq(type, e->type))
+ continue;
+ if (event_id != e->event)
+ continue;
+ if (e->num_ports && port >= e->num_ports) {
+ dev_warn(ccn->dev, "Invalid port %d for node/XP %d!\n",
+ port, node_xp);
+ return -EINVAL;
+ }
+ if (e->num_vcs && vc >= e->num_vcs) {
+ dev_warn(ccn->dev, "Invalid vc %d for node/XP %d!\n",
+ port, node_xp);
+ return -EINVAL;
+ }
+ valid = 1;
+ }
+ if (!valid) {
+ dev_warn(ccn->dev, "Invalid event 0x%x for node/XP %d!\n",
+ event_id, node_xp);
+ return -EINVAL;
+ }
+
+ /* Watchpoint-based event for a node is actually set on XP */
+ if (event_id == CCN_EVENT_WATCHPOINT && type != CCN_TYPE_XP) {
+ u32 port;
+
+ type = CCN_TYPE_XP;
+ port = arm_ccn_node_to_xp_port(node_xp);
+ node_xp = arm_ccn_node_to_xp(node_xp);
+
+ arm_ccn_pmu_config_set(&event->attr.config,
+ node_xp, type, port);
+ }
+
+ /* Allocate the cycle counter */
+ if (type == CCN_TYPE_CYCLES) {
+ if (test_and_set_bit(CCN_IDX_PMU_CYCLE_COUNTER,
+ ccn->dt.pmu_counters_mask))
+ return -EAGAIN;
+
+ hw->idx = CCN_IDX_PMU_CYCLE_COUNTER;
+ ccn->dt.pmu_counters[CCN_IDX_PMU_CYCLE_COUNTER].event = event;
+
+ return 0;
+ }
+
+ /* Allocate an event counter */
+ hw->idx = arm_ccn_pmu_alloc_bit(ccn->dt.pmu_counters_mask,
+ CCN_NUM_PMU_EVENT_COUNTERS);
+ if (hw->idx < 0) {
+ dev_warn(ccn->dev, "No more counters available!\n");
+ return -EAGAIN;
+ }
+
+ if (type == CCN_TYPE_XP)
+ source = &ccn->xp[node_xp];
+ else
+ source = &ccn->node[node_xp];
+ ccn->dt.pmu_counters[hw->idx].source = source;
+
+ /* Allocate an event source or a watchpoint */
+ if (type == CCN_TYPE_XP && event_id == CCN_EVENT_WATCHPOINT)
+ hw->config_base = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask,
+ CCN_NUM_XP_WATCHPOINTS);
+ else
+ hw->config_base = arm_ccn_pmu_alloc_bit(source->pmu_events_mask,
+ CCN_NUM_PMU_EVENTS);
+ if (hw->config_base < 0) {
+ dev_warn(ccn->dev, "No more event sources/watchpoints on node/XP %d!\n",
+ node_xp);
+ clear_bit(hw->idx, ccn->dt.pmu_counters_mask);
+ return -EAGAIN;
+ }
+
+ ccn->dt.pmu_counters[hw->idx].event = event;
+
+ return 0;
+}
+
+static void arm_ccn_pmu_event_free(struct perf_event *event)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+
+ if (hw->idx == CCN_IDX_PMU_CYCLE_COUNTER) {
+ clear_bit(CCN_IDX_PMU_CYCLE_COUNTER, ccn->dt.pmu_counters_mask);
+ } else {
+ struct arm_ccn_component *source =
+ ccn->dt.pmu_counters[hw->idx].source;
+
+ if (CCN_CONFIG_TYPE(event->attr.config) == CCN_TYPE_XP &&
+ CCN_CONFIG_EVENT(event->attr.config) ==
+ CCN_EVENT_WATCHPOINT)
+ clear_bit(hw->config_base, source->xp.dt_cmp_mask);
+ else
+ clear_bit(hw->config_base, source->pmu_events_mask);
+ clear_bit(hw->idx, ccn->dt.pmu_counters_mask);
+ }
+
+ ccn->dt.pmu_counters[hw->idx].source = NULL;
+ ccn->dt.pmu_counters[hw->idx].event = NULL;
+}
+
+static u64 arm_ccn_pmu_read_counter(struct arm_ccn *ccn, int idx)
+{
+ u64 res;
+
+ if (idx == CCN_IDX_PMU_CYCLE_COUNTER) {
+#ifdef readq
+ res = readq(ccn->dt.base + CCN_DT_PMCCNTR);
+#else
+ /* 40 bit counter, can do snapshot and read in two parts */
+ writel(0x1, ccn->dt.base + CCN_DT_PMSR_REQ);
+ while (!(readl(ccn->dt.base + CCN_DT_PMSR) & 0x1))
+ ;
+ writel(0x1, ccn->dt.base + CCN_DT_PMSR_CLR);
+ res = readl(ccn->dt.base + CCN_DT_PMCCNTRSR + 4) & 0xff;
+ res <<= 32;
+ res |= readl(ccn->dt.base + CCN_DT_PMCCNTRSR);
+#endif
+ } else {
+ res = readl(ccn->dt.base + CCN_DT_PMEVCNT(idx));
+ }
+
+ return res;
+}
+
+static void arm_ccn_pmu_event_update(struct perf_event *event)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ u64 prev_count, new_count, mask;
+
+ do {
+ prev_count = local64_read(&hw->prev_count);
+ new_count = arm_ccn_pmu_read_counter(ccn, hw->idx);
+ } while (local64_xchg(&hw->prev_count, new_count) != prev_count);
+
+ mask = (1LLU << (hw->idx == CCN_IDX_PMU_CYCLE_COUNTER ? 40 : 32)) - 1;
+
+ local64_add((new_count - prev_count) & mask, &event->count);
+}
+
+static void arm_ccn_pmu_xp_dt_config(struct perf_event *event, int enable)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ struct arm_ccn_component *xp;
+ u32 val, dt_cfg;
+
+ if (CCN_CONFIG_TYPE(event->attr.config) == CCN_TYPE_XP)
+ xp = &ccn->xp[CCN_CONFIG_XP(event->attr.config)];
+ else
+ xp = &ccn->xp[arm_ccn_node_to_xp(
+ CCN_CONFIG_NODE(event->attr.config))];
+
+ if (enable)
+ dt_cfg = hw->event_base;
+ else
+ dt_cfg = CCN_XP_DT_CONFIG__DT_CFG__PASS_THROUGH;
+
+ spin_lock(&ccn->dt.config_lock);
+
+ val = readl(xp->base + CCN_XP_DT_CONFIG);
+ val &= ~(CCN_XP_DT_CONFIG__DT_CFG__MASK <<
+ CCN_XP_DT_CONFIG__DT_CFG__SHIFT(hw->idx));
+ val |= dt_cfg << CCN_XP_DT_CONFIG__DT_CFG__SHIFT(hw->idx);
+ writel(val, xp->base + CCN_XP_DT_CONFIG);
+
+ spin_unlock(&ccn->dt.config_lock);
+}
+
+static void arm_ccn_pmu_event_start(struct perf_event *event, int flags)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+
+ local64_set(&event->hw.prev_count,
+ arm_ccn_pmu_read_counter(ccn, hw->idx));
+ hw->state = 0;
+
+ if (!ccn->irq_used)
+ hrtimer_start(&ccn->dt.hrtimer, arm_ccn_pmu_timer_period(),
+ HRTIMER_MODE_REL);
+
+ /* Set the DT bus input, engaging the counter */
+ arm_ccn_pmu_xp_dt_config(event, 1);
+}
+
+static void arm_ccn_pmu_event_stop(struct perf_event *event, int flags)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ u64 timeout;
+
+ /* Disable counting, setting the DT bus to pass-through mode */
+ arm_ccn_pmu_xp_dt_config(event, 0);
+
+ if (!ccn->irq_used)
+ hrtimer_cancel(&ccn->dt.hrtimer);
+
+ /* Let the DT bus drain */
+ timeout = arm_ccn_pmu_read_counter(ccn, CCN_IDX_PMU_CYCLE_COUNTER) +
+ ccn->num_xps;
+ while (arm_ccn_pmu_read_counter(ccn, CCN_IDX_PMU_CYCLE_COUNTER) <
+ timeout)
+ cpu_relax();
+
+ if (flags & PERF_EF_UPDATE)
+ arm_ccn_pmu_event_update(event);
+
+ hw->state |= PERF_HES_STOPPED;
+}
+
+static void arm_ccn_pmu_xp_watchpoint_config(struct perf_event *event)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ struct arm_ccn_component *source =
+ ccn->dt.pmu_counters[hw->idx].source;
+ unsigned long wp = hw->config_base;
+ u32 val;
+ u64 cmp_l = event->attr.config1;
+ u64 cmp_h = event->attr.config2;
+ u64 mask_l = ccn->dt.cmp_mask[CCN_CONFIG_MASK(event->attr.config)].l;
+ u64 mask_h = ccn->dt.cmp_mask[CCN_CONFIG_MASK(event->attr.config)].h;
+
+ hw->event_base = CCN_XP_DT_CONFIG__DT_CFG__WATCHPOINT(wp);
+
+ /* Direction (RX/TX), device (port) & virtual channel */
+ val = readl(source->base + CCN_XP_DT_INTERFACE_SEL);
+ val &= ~(CCN_XP_DT_INTERFACE_SEL__DT_IO_SEL__MASK <<
+ CCN_XP_DT_INTERFACE_SEL__DT_IO_SEL__SHIFT(wp));
+ val |= CCN_CONFIG_DIR(event->attr.config) <<
+ CCN_XP_DT_INTERFACE_SEL__DT_IO_SEL__SHIFT(wp);
+ val &= ~(CCN_XP_DT_INTERFACE_SEL__DT_DEV_SEL__MASK <<
+ CCN_XP_DT_INTERFACE_SEL__DT_DEV_SEL__SHIFT(wp));
+ val |= CCN_CONFIG_PORT(event->attr.config) <<
+ CCN_XP_DT_INTERFACE_SEL__DT_DEV_SEL__SHIFT(wp);
+ val &= ~(CCN_XP_DT_INTERFACE_SEL__DT_VC_SEL__MASK <<
+ CCN_XP_DT_INTERFACE_SEL__DT_VC_SEL__SHIFT(wp));
+ val |= CCN_CONFIG_VC(event->attr.config) <<
+ CCN_XP_DT_INTERFACE_SEL__DT_VC_SEL__SHIFT(wp);
+ writel(val, source->base + CCN_XP_DT_INTERFACE_SEL);
+
+ /* Comparison values */
+ writel(cmp_l & 0xffffffff, source->base + CCN_XP_DT_CMP_VAL_L(wp));
+ writel((cmp_l >> 32) & 0xefffffff,
+ source->base + CCN_XP_DT_CMP_VAL_L(wp) + 4);
+ writel(cmp_h & 0xffffffff, source->base + CCN_XP_DT_CMP_VAL_H(wp));
+ writel((cmp_h >> 32) & 0x0fffffff,
+ source->base + CCN_XP_DT_CMP_VAL_H(wp) + 4);
+
+ /* Mask */
+ writel(mask_l & 0xffffffff, source->base + CCN_XP_DT_CMP_MASK_L(wp));
+ writel((mask_l >> 32) & 0xefffffff,
+ source->base + CCN_XP_DT_CMP_MASK_L(wp) + 4);
+ writel(mask_h & 0xffffffff, source->base + CCN_XP_DT_CMP_MASK_H(wp));
+ writel((mask_h >> 32) & 0x0fffffff,
+ source->base + CCN_XP_DT_CMP_MASK_H(wp) + 4);
+}
+
+static void arm_ccn_pmu_xp_event_config(struct perf_event *event)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ struct arm_ccn_component *source =
+ ccn->dt.pmu_counters[hw->idx].source;
+ u32 val, id;
+
+ hw->event_base = CCN_XP_DT_CONFIG__DT_CFG__XP_PMU_EVENT(hw->config_base);
+
+ id = (CCN_CONFIG_VC(event->attr.config) << 4) |
+ (CCN_CONFIG_PORT(event->attr.config) << 3) |
+ (CCN_CONFIG_EVENT(event->attr.config) << 0);
+
+ val = readl(source->base + CCN_XP_PMU_EVENT_SEL);
+ val &= ~(CCN_XP_PMU_EVENT_SEL__ID__MASK <<
+ CCN_XP_PMU_EVENT_SEL__ID__SHIFT(hw->config_base));
+ val |= id << CCN_XP_PMU_EVENT_SEL__ID__SHIFT(hw->config_base);
+ writel(val, source->base + CCN_XP_PMU_EVENT_SEL);
+}
+
+static void arm_ccn_pmu_node_event_config(struct perf_event *event)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ struct arm_ccn_component *source =
+ ccn->dt.pmu_counters[hw->idx].source;
+ u32 type = CCN_CONFIG_TYPE(event->attr.config);
+ u32 val, port;
+
+ port = arm_ccn_node_to_xp_port(CCN_CONFIG_NODE(event->attr.config));
+ hw->event_base = CCN_XP_DT_CONFIG__DT_CFG__DEVICE_PMU_EVENT(port,
+ hw->config_base);
+
+ /* These *_event_sel regs should be identical, but let's make sure... */
+ BUILD_BUG_ON(CCN_HNF_PMU_EVENT_SEL != CCN_SBAS_PMU_EVENT_SEL);
+ BUILD_BUG_ON(CCN_SBAS_PMU_EVENT_SEL != CCN_RNI_PMU_EVENT_SEL);
+ BUILD_BUG_ON(CCN_HNF_PMU_EVENT_SEL__ID__SHIFT(1) !=
+ CCN_SBAS_PMU_EVENT_SEL__ID__SHIFT(1));
+ BUILD_BUG_ON(CCN_SBAS_PMU_EVENT_SEL__ID__SHIFT(1) !=
+ CCN_RNI_PMU_EVENT_SEL__ID__SHIFT(1));
+ BUILD_BUG_ON(CCN_HNF_PMU_EVENT_SEL__ID__MASK !=
+ CCN_SBAS_PMU_EVENT_SEL__ID__MASK);
+ BUILD_BUG_ON(CCN_SBAS_PMU_EVENT_SEL__ID__MASK !=
+ CCN_RNI_PMU_EVENT_SEL__ID__MASK);
+ if (WARN_ON(type != CCN_TYPE_HNF && type != CCN_TYPE_SBAS &&
+ !arm_ccn_pmu_type_eq(type, CCN_TYPE_RNI_3P)))
+ return;
+
+ /* Set the event id for the pre-allocated counter */
+ val = readl(source->base + CCN_HNF_PMU_EVENT_SEL);
+ val &= ~(CCN_HNF_PMU_EVENT_SEL__ID__MASK <<
+ CCN_HNF_PMU_EVENT_SEL__ID__SHIFT(hw->config_base));
+ val |= CCN_CONFIG_EVENT(event->attr.config) <<
+ CCN_HNF_PMU_EVENT_SEL__ID__SHIFT(hw->config_base);
+ writel(val, source->base + CCN_HNF_PMU_EVENT_SEL);
+}
+
+static void arm_ccn_pmu_event_config(struct perf_event *event)
+{
+ struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ u32 xp, offset, val;
+
+ /* Cycle counter requires no setup */
+ if (hw->idx == CCN_IDX_PMU_CYCLE_COUNTER)
+ return;
+
+ if (CCN_CONFIG_TYPE(event->attr.config) == CCN_TYPE_XP)
+ xp = CCN_CONFIG_XP(event->attr.config);
+ else
+ xp = arm_ccn_node_to_xp(CCN_CONFIG_NODE(event->attr.config));
+
+ spin_lock(&ccn->dt.config_lock);
+
+ /* Set the DT bus "distance" register */
+ offset = (hw->idx / 4) * 4;
+ val = readl(ccn->dt.base + CCN_DT_ACTIVE_DSM + offset);
+ val &= ~(CCN_DT_ACTIVE_DSM__DSM_ID__MASK <<
+ CCN_DT_ACTIVE_DSM__DSM_ID__SHIFT(hw->idx % 4));
+ val |= xp << CCN_DT_ACTIVE_DSM__DSM_ID__SHIFT(hw->idx % 4);
+ writel(val, ccn->dt.base + CCN_DT_ACTIVE_DSM + offset);
+
+ if (CCN_CONFIG_TYPE(event->attr.config) == CCN_TYPE_XP) {
+ if (CCN_CONFIG_EVENT(event->attr.config) ==
+ CCN_EVENT_WATCHPOINT)
+ arm_ccn_pmu_xp_watchpoint_config(event);
+ else
+ arm_ccn_pmu_xp_event_config(event);
+ } else {
+ arm_ccn_pmu_node_event_config(event);
+ }
+
+ spin_unlock(&ccn->dt.config_lock);
+}
+
+static int arm_ccn_pmu_event_add(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hw = &event->hw;
+
+ arm_ccn_pmu_event_config(event);
+
+ hw->state = PERF_HES_STOPPED;
+
+ if (flags & PERF_EF_START)
+ arm_ccn_pmu_event_start(event, PERF_EF_UPDATE);
+
+ return 0;
+}
+
+static void arm_ccn_pmu_event_del(struct perf_event *event, int flags)
+{
+ arm_ccn_pmu_event_stop(event, PERF_EF_UPDATE);
+
+ arm_ccn_pmu_event_free(event);
+}
+
+static void arm_ccn_pmu_event_read(struct perf_event *event)
+{
+ arm_ccn_pmu_event_update(event);
+}
+
+static irqreturn_t arm_ccn_pmu_overflow_handler(struct arm_ccn_dt *dt)
+{
+ u32 pmovsr = readl(dt->base + CCN_DT_PMOVSR);
+ int idx;
+
+ if (!pmovsr)
+ return IRQ_NONE;
+
+ writel(pmovsr, dt->base + CCN_DT_PMOVSR_CLR);
+
+ BUILD_BUG_ON(CCN_IDX_PMU_CYCLE_COUNTER != CCN_NUM_PMU_EVENT_COUNTERS);
+
+ for (idx = 0; idx < CCN_NUM_PMU_EVENT_COUNTERS + 1; idx++) {
+ struct perf_event *event = dt->pmu_counters[idx].event;
+ int overflowed = pmovsr & BIT(idx);
+
+ WARN_ON_ONCE(overflowed && !event);
+
+ if (!event || !overflowed)
+ continue;
+
+ arm_ccn_pmu_event_update(event);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static enum hrtimer_restart arm_ccn_pmu_timer_handler(struct hrtimer *hrtimer)
+{
+ struct arm_ccn_dt *dt = container_of(hrtimer, struct arm_ccn_dt,
+ hrtimer);
+ unsigned long flags;
+
+ local_irq_save(flags);
+ arm_ccn_pmu_overflow_handler(dt);
+ local_irq_restore(flags);
+
+ hrtimer_forward_now(hrtimer, arm_ccn_pmu_timer_period());
+ return HRTIMER_RESTART;
+}
+
+
+static DEFINE_IDA(arm_ccn_pmu_ida);
+
+static int arm_ccn_pmu_init(struct arm_ccn *ccn)
+{
+ int i;
+ char *name;
+
+ /* Initialize DT subsystem */
+ ccn->dt.base = ccn->base + CCN_REGION_SIZE;
+ spin_lock_init(&ccn->dt.config_lock);
+ writel(CCN_DT_CTL__DT_EN, ccn->dt.base + CCN_DT_CTL);
+ writel(CCN_DT_PMCR__OVFL_INTR_EN | CCN_DT_PMCR__PMU_EN,
+ ccn->dt.base + CCN_DT_PMCR);
+ writel(0x1, ccn->dt.base + CCN_DT_PMSR_CLR);
+ for (i = 0; i < ccn->num_xps; i++) {
+ writel(0, ccn->xp[i].base + CCN_XP_DT_CONFIG);
+ writel((CCN_XP_DT_CONTROL__WP_ARM_SEL__ALWAYS <<
+ CCN_XP_DT_CONTROL__WP_ARM_SEL__SHIFT(0)) |
+ (CCN_XP_DT_CONTROL__WP_ARM_SEL__ALWAYS <<
+ CCN_XP_DT_CONTROL__WP_ARM_SEL__SHIFT(1)) |
+ CCN_XP_DT_CONTROL__DT_ENABLE,
+ ccn->xp[i].base + CCN_XP_DT_CONTROL);
+ }
+ ccn->dt.cmp_mask[CCN_IDX_MASK_ANY].l = ~0;
+ ccn->dt.cmp_mask[CCN_IDX_MASK_ANY].h = ~0;
+ ccn->dt.cmp_mask[CCN_IDX_MASK_EXACT].l = 0;
+ ccn->dt.cmp_mask[CCN_IDX_MASK_EXACT].h = 0;
+ ccn->dt.cmp_mask[CCN_IDX_MASK_ORDER].l = ~0;
+ ccn->dt.cmp_mask[CCN_IDX_MASK_ORDER].h = ~(0x1 << 15);
+ ccn->dt.cmp_mask[CCN_IDX_MASK_OPCODE].l = ~0;
+ ccn->dt.cmp_mask[CCN_IDX_MASK_OPCODE].h = ~(0x1f << 9);
+
+ /* Get a convenient /sys/event_source/devices/ name */
+ ccn->dt.id = ida_simple_get(&arm_ccn_pmu_ida, 0, 0, GFP_KERNEL);
+ if (ccn->dt.id == 0) {
+ name = "ccn";
+ } else {
+ int len = snprintf(NULL, 0, "ccn_%d", ccn->dt.id);
+
+ name = devm_kzalloc(ccn->dev, len + 1, GFP_KERNEL);
+ snprintf(name, len + 1, "ccn_%d", ccn->dt.id);
+ }
+
+ /* Perf driver registration */
+ ccn->dt.pmu = (struct pmu) {
+ .attr_groups = arm_ccn_pmu_attr_groups,
+ .task_ctx_nr = perf_invalid_context,
+ .event_init = arm_ccn_pmu_event_init,
+ .add = arm_ccn_pmu_event_add,
+ .del = arm_ccn_pmu_event_del,
+ .start = arm_ccn_pmu_event_start,
+ .stop = arm_ccn_pmu_event_stop,
+ .read = arm_ccn_pmu_event_read,
+ };
+
+ /* No overflow interrupt? Have to use a timer instead. */
+ if (!ccn->irq_used) {
+ dev_info(ccn->dev, "No access to interrupts, using timer.\n");
+ hrtimer_init(&ccn->dt.hrtimer, CLOCK_MONOTONIC,
+ HRTIMER_MODE_REL);
+ ccn->dt.hrtimer.function = arm_ccn_pmu_timer_handler;
+ }
+
+ return perf_pmu_register(&ccn->dt.pmu, name, -1);
+}
+
+static void arm_ccn_pmu_cleanup(struct arm_ccn *ccn)
+{
+ int i;
+
+ for (i = 0; i < ccn->num_xps; i++)
+ writel(0, ccn->xp[i].base + CCN_XP_DT_CONTROL);
+ writel(0, ccn->dt.base + CCN_DT_PMCR);
+ perf_pmu_unregister(&ccn->dt.pmu);
+ ida_simple_remove(&arm_ccn_pmu_ida, ccn->dt.id);
+}
+
+
+static int arm_ccn_for_each_valid_region(struct arm_ccn *ccn,
+ int (*callback)(struct arm_ccn *ccn, int region,
+ void __iomem *base, u32 type, u32 id))
+{
+ int region;
+
+ for (region = 0; region < CCN_NUM_REGIONS; region++) {
+ u32 val, type, id;
+ void __iomem *base;
+ int err;
+
+ val = readl(ccn->base + CCN_MN_OLY_COMP_LIST_63_0 +
+ 4 * (region / 32));
+ if (!(val & (1 << (region % 32))))
+ continue;
+
+ base = ccn->base + region * CCN_REGION_SIZE;
+ val = readl(base + CCN_ALL_OLY_ID);
+ type = (val >> CCN_ALL_OLY_ID__OLY_ID__SHIFT) &
+ CCN_ALL_OLY_ID__OLY_ID__MASK;
+ id = (val >> CCN_ALL_OLY_ID__NODE_ID__SHIFT) &
+ CCN_ALL_OLY_ID__NODE_ID__MASK;
+
+ err = callback(ccn, region, base, type, id);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static int arm_ccn_get_nodes_num(struct arm_ccn *ccn, int region,
+ void __iomem *base, u32 type, u32 id)
+{
+
+ if (type == CCN_TYPE_XP && id >= ccn->num_xps)
+ ccn->num_xps = id + 1;
+ else if (id >= ccn->num_nodes)
+ ccn->num_nodes = id + 1;
+
+ return 0;
+}
+
+static int arm_ccn_init_nodes(struct arm_ccn *ccn, int region,
+ void __iomem *base, u32 type, u32 id)
+{
+ struct arm_ccn_component *component;
+
+ dev_dbg(ccn->dev, "Region %d: id=%u, type=0x%02x\n", region, id, type);
+
+ switch (type) {
+ case CCN_TYPE_MN:
+ case CCN_TYPE_DT:
+ return 0;
+ case CCN_TYPE_XP:
+ component = &ccn->xp[id];
+ break;
+ case CCN_TYPE_SBSX:
+ ccn->sbsx_present = 1;
+ component = &ccn->node[id];
+ break;
+ case CCN_TYPE_SBAS:
+ ccn->sbas_present = 1;
+ /* Fall-through */
+ default:
+ component = &ccn->node[id];
+ break;
+ }
+
+ component->base = base;
+ component->type = type;
+
+ return 0;
+}
+
+
+static irqreturn_t arm_ccn_error_handler(struct arm_ccn *ccn,
+ const u32 *err_sig_val)
+{
+ /* This should be really handled by firmware... */
+ dev_err(ccn->dev, "Error reported in %08x%08x%08x%08x%08x%08x.\n",
+ err_sig_val[5], err_sig_val[4], err_sig_val[3],
+ err_sig_val[2], err_sig_val[1], err_sig_val[0]);
+ dev_err(ccn->dev, "Disabling interrupt generation for all errors.\n");
+ writel(CCN_MN_ERRINT_STATUS__ALL_ERRORS__DISABLE,
+ ccn->base + CCN_MN_ERRINT_STATUS);
+
+ return IRQ_HANDLED;
+}
+
+
+static irqreturn_t arm_ccn_irq_handler(int irq, void *dev_id)
+{
+ irqreturn_t res = IRQ_NONE;
+ struct arm_ccn *ccn = dev_id;
+ u32 err_sig_val[6];
+ u32 err_or;
+ int i;
+
+ /* PMU overflow is a special case */
+ err_or = err_sig_val[0] = readl(ccn->base + CCN_MN_ERR_SIG_VAL_63_0);
+ if (err_or & CCN_MN_ERR_SIG_VAL_63_0__DT) {
+ err_or &= ~CCN_MN_ERR_SIG_VAL_63_0__DT;
+ res = arm_ccn_pmu_overflow_handler(&ccn->dt);
+ }
+
+ /* Have to read all err_sig_vals to clear them */
+ for (i = 1; i < ARRAY_SIZE(err_sig_val); i++) {
+ err_sig_val[i] = readl(ccn->base +
+ CCN_MN_ERR_SIG_VAL_63_0 + i * 4);
+ err_or |= err_sig_val[i];
+ }
+ if (err_or)
+ res |= arm_ccn_error_handler(ccn, err_sig_val);
+
+ if (res != IRQ_NONE)
+ writel(CCN_MN_ERRINT_STATUS__INTREQ__DESSERT,
+ ccn->base + CCN_MN_ERRINT_STATUS);
+
+ return res;
+}
+
+
+static int arm_ccn_probe(struct platform_device *pdev)
+{
+ struct arm_ccn *ccn;
+ struct resource *res;
+ int err;
+
+ ccn = devm_kzalloc(&pdev->dev, sizeof(*ccn), GFP_KERNEL);
+ if (!ccn)
+ return -ENOMEM;
+ ccn->dev = &pdev->dev;
+ platform_set_drvdata(pdev, ccn);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ if (!devm_request_mem_region(ccn->dev, res->start,
+ resource_size(res), pdev->name))
+ return -EBUSY;
+
+ ccn->base = devm_ioremap(ccn->dev, res->start,
+ resource_size(res));
+ if (!ccn->base)
+ return -EFAULT;
+
+ res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!res)
+ return -EINVAL;
+
+ /* Check if we can use the interrupt */
+ writel(CCN_MN_ERRINT_STATUS__PMU_EVENTS__DISABLE,
+ ccn->base + CCN_MN_ERRINT_STATUS);
+ if (readl(ccn->base + CCN_MN_ERRINT_STATUS) &
+ CCN_MN_ERRINT_STATUS__PMU_EVENTS__DISABLED) {
+ /* Can set 'disable' bits, so can acknowledge interrupts */
+ writel(CCN_MN_ERRINT_STATUS__PMU_EVENTS__ENABLE,
+ ccn->base + CCN_MN_ERRINT_STATUS);
+ err = devm_request_irq(ccn->dev, res->start,
+ arm_ccn_irq_handler, 0, dev_name(ccn->dev),
+ ccn);
+ if (err)
+ return err;
+
+ ccn->irq_used = 1;
+ }
+
+
+ /* Build topology */
+
+ err = arm_ccn_for_each_valid_region(ccn, arm_ccn_get_nodes_num);
+ if (err)
+ return err;
+
+ ccn->node = devm_kzalloc(ccn->dev, sizeof(*ccn->node) * ccn->num_nodes,
+ GFP_KERNEL);
+ ccn->xp = devm_kzalloc(ccn->dev, sizeof(*ccn->node) * ccn->num_xps,
+ GFP_KERNEL);
+ if (!ccn->node || !ccn->xp)
+ return -ENOMEM;
+
+ err = arm_ccn_for_each_valid_region(ccn, arm_ccn_init_nodes);
+ if (err)
+ return err;
+
+ return arm_ccn_pmu_init(ccn);
+}
+
+static int arm_ccn_remove(struct platform_device *pdev)
+{
+ struct arm_ccn *ccn = platform_get_drvdata(pdev);
+
+ arm_ccn_pmu_cleanup(ccn);
+
+ return 0;
+}
+
+static const struct of_device_id arm_ccn_match[] = {
+ { .compatible = "arm,ccn-504", },
+ {},
+};
+
+static struct platform_driver arm_ccn_driver = {
+ .driver = {
+ .name = "arm-ccn",
+ .of_match_table = arm_ccn_match,
+ },
+ .probe = arm_ccn_probe,
+ .remove = arm_ccn_remove,
+};
+
+static int __init arm_ccn_init(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(arm_ccn_pmu_events); i++)
+ arm_ccn_pmu_events_attrs[i] = &arm_ccn_pmu_events[i].attr.attr;
+
+ return platform_driver_register(&arm_ccn_driver);
+}
+
+static void __exit arm_ccn_exit(void)
+{
+ platform_driver_unregister(&arm_ccn_driver);
+}
+
+module_init(arm_ccn_init);
+module_exit(arm_ccn_exit);
+
+MODULE_AUTHOR("Pawel Moll <pawel.moll@....com>");
+MODULE_LICENSE("GPL");
--
1.9.1
--
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