* [PATCH v4 0/4] perf: Add APM X-Gene SoC Performance Monitoring Unit driver
@ 2016-06-22 18:06 Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 1/4] MAINTAINERS: Add entry for APM X-Gene SoC PMU driver Tai Nguyen
` (3 more replies)
0 siblings, 4 replies; 15+ messages in thread
From: Tai Nguyen @ 2016-06-22 18:06 UTC (permalink / raw)
To: mark.rutland, will.deacon, catalin.marinas
Cc: linux-kernel, devicetree, linux-arm-kernel, patches, Tai Nguyen
In addition to the X-Gene ARM CPU performance monitoring unit (PMU), there
are PMU for the SoC system devices such as L3 cache(s), I/O bridge(s),
memory controller bridges and memory. These PMU devices are loosely
architected to follow the same model as the PMU for ARM cores.
Signed-off-by: Tai Nguyen <ttnguyen@apm.com>
---
v4:
* Alphabetically sorting header files
* Remove dynamic allocation for PMU format and event attribute groups
Create shared constant attribute groups per each class
* Remove perf_sample_data as this perf driver doesn't support sampling
* Consistently use the PCP_PMU_V{1,2} defines
* Set affinity to make sure the overflow interrupt is handled by the
same assigned CPU
v3:
* Remove index property use in PMU device sub nodes
v2:
* Use bitmask for event asignned counter mask pmu_dev->cntr_assign_mask
* Remove unnecessary spinlocks in perf add/del operations
* Remove unnecessary condition checks
* Enforce CPU assignment to one CPU for perf operarations
* Set the task_ctx_nr to perf_invalid_context for perf driver
* Remove irrelevant pt_rregs
* Change perf sysfs attributes to be fixed instead of dynamic
* Fix checking for an ACPI companion device instead of EFI enable
* Add documentation for config/config1 fields format and perf tool example
---
Tai Nguyen (4):
MAINTAINERS: Add entry for APM X-Gene SoC PMU driver
Documentation: Add documentation for APM X-Gene SoC PMU DTS binding
perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
arm64: dts: apm: Add APM X-Gene SoC PMU DTS entries
.../devicetree/bindings/perf/apm-xgene-pmu.txt | 112 ++
Documentation/perf/xgene-pmu.txt | 48 +
MAINTAINERS | 8 +
arch/arm64/boot/dts/apm/apm-storm.dtsi | 58 +
drivers/perf/Kconfig | 7 +
drivers/perf/Makefile | 1 +
drivers/perf/xgene_pmu.c | 1437 ++++++++++++++++++++
7 files changed, 1671 insertions(+)
create mode 100644 Documentation/devicetree/bindings/perf/apm-xgene-pmu.txt
create mode 100644 Documentation/perf/xgene-pmu.txt
create mode 100644 drivers/perf/xgene_pmu.c
--
1.9.1
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v4 1/4] MAINTAINERS: Add entry for APM X-Gene SoC PMU driver
2016-06-22 18:06 [PATCH v4 0/4] perf: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
@ 2016-06-22 18:06 ` Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 2/4] Documentation: Add documentation for APM X-Gene SoC PMU DTS binding Tai Nguyen
` (2 subsequent siblings)
3 siblings, 0 replies; 15+ messages in thread
From: Tai Nguyen @ 2016-06-22 18:06 UTC (permalink / raw)
To: mark.rutland, will.deacon, catalin.marinas
Cc: linux-kernel, devicetree, linux-arm-kernel, patches, Tai Nguyen
Signed-off-by: Tai Nguyen <ttnguyen@apm.com>
---
MAINTAINERS | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 4978dc1..3bd4143 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8593,6 +8593,14 @@ L: linux-scsi@vger.kernel.org
S: Supported
F: drivers/scsi/pm8001/
+PMU-XGENE
+APPLIED MICRO (APM) X-GENE SOC PMU
+M: Tai Nguyen <ttnguyen@apm.com>
+S: Supported
+F: drivers/perf/xgene_pmu.c
+F: Documentation/perf/xgene-pmu.txt
+F: Documentation/devicetree/bindings/perf/apm-xgene-pmu.txt
+
POSIX CLOCKS and TIMERS
M: Thomas Gleixner <tglx@linutronix.de>
L: linux-kernel@vger.kernel.org
--
1.9.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v4 2/4] Documentation: Add documentation for APM X-Gene SoC PMU DTS binding
2016-06-22 18:06 [PATCH v4 0/4] perf: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 1/4] MAINTAINERS: Add entry for APM X-Gene SoC PMU driver Tai Nguyen
@ 2016-06-22 18:06 ` Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 4/4] arm64: dts: apm: Add APM X-Gene SoC PMU DTS entries Tai Nguyen
3 siblings, 0 replies; 15+ messages in thread
From: Tai Nguyen @ 2016-06-22 18:06 UTC (permalink / raw)
To: mark.rutland, will.deacon, catalin.marinas
Cc: linux-kernel, devicetree, linux-arm-kernel, patches, Tai Nguyen
Signed-off-by: Tai Nguyen <ttnguyen@apm.com>
Acked-by: Rob Herring <robh@kernel.org>
---
.../devicetree/bindings/perf/apm-xgene-pmu.txt | 112 +++++++++++++++++++++
1 file changed, 112 insertions(+)
create mode 100644 Documentation/devicetree/bindings/perf/apm-xgene-pmu.txt
diff --git a/Documentation/devicetree/bindings/perf/apm-xgene-pmu.txt b/Documentation/devicetree/bindings/perf/apm-xgene-pmu.txt
new file mode 100644
index 0000000..afb11cf
--- /dev/null
+++ b/Documentation/devicetree/bindings/perf/apm-xgene-pmu.txt
@@ -0,0 +1,112 @@
+* APM X-Gene SoC PMU bindings
+
+This is APM X-Gene SoC PMU (Performance Monitoring Unit) module.
+The following PMU devices are supported:
+
+ L3C - L3 cache controller
+ IOB - IO bridge
+ MCB - Memory controller bridge
+ MC - Memory controller
+
+The following section describes the SoC PMU DT node binding.
+
+Required properties:
+- compatible : Shall be "apm,xgene-pmu" for revision 1 or
+ "apm,xgene-pmu-v2" for revision 2.
+- regmap-csw : Regmap of the CPU switch fabric (CSW) resource.
+- regmap-mcba : Regmap of the MCB-A (memory bridge) resource.
+- regmap-mcbb : Regmap of the MCB-B (memory bridge) resource.
+- reg : First resource shall be the CPU bus PMU resource.
+- interrupts : Interrupt-specifier for PMU IRQ.
+
+Required properties for L3C subnode:
+- compatible : Shall be "apm,xgene-pmu-l3c".
+- reg : First resource shall be the L3C PMU resource.
+
+Required properties for IOB subnode:
+- compatible : Shall be "apm,xgene-pmu-iob".
+- reg : First resource shall be the IOB PMU resource.
+
+Required properties for MCB subnode:
+- compatible : Shall be "apm,xgene-pmu-mcb".
+- reg : First resource shall be the MCB PMU resource.
+- enable-bit-index : The bit indicates if the according MCB is enabled.
+
+Required properties for MC subnode:
+- compatible : Shall be "apm,xgene-pmu-mc".
+- reg : First resource shall be the MC PMU resource.
+- enable-bit-index : The bit indicates if the according MC is enabled.
+
+Example:
+ csw: csw@7e200000 {
+ compatible = "apm,xgene-csw", "syscon";
+ reg = <0x0 0x7e200000 0x0 0x1000>;
+ };
+
+ mcba: mcba@7e700000 {
+ compatible = "apm,xgene-mcb", "syscon";
+ reg = <0x0 0x7e700000 0x0 0x1000>;
+ };
+
+ mcbb: mcbb@7e720000 {
+ compatible = "apm,xgene-mcb", "syscon";
+ reg = <0x0 0x7e720000 0x0 0x1000>;
+ };
+
+ pmu: pmu@78810000 {
+ compatible = "apm,xgene-pmu-v2";
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+ regmap-csw = <&csw>;
+ regmap-mcba = <&mcba>;
+ regmap-mcbb = <&mcbb>;
+ reg = <0x0 0x78810000 0x0 0x1000>;
+ interrupts = <0x0 0x22 0x4>;
+
+ pmul3c@7e610000 {
+ compatible = "apm,xgene-pmu-l3c";
+ reg = <0x0 0x7e610000 0x0 0x1000>;
+ };
+
+ pmuiob@7e940000 {
+ compatible = "apm,xgene-pmu-iob";
+ reg = <0x0 0x7e940000 0x0 0x1000>;
+ };
+
+ pmucmcb@7e710000 {
+ compatible = "apm,xgene-pmu-mcb";
+ reg = <0x0 0x7e710000 0x0 0x1000>;
+ enable-bit-index = <0>;
+ };
+
+ pmucmcb@7e730000 {
+ compatible = "apm,xgene-pmu-mcb";
+ reg = <0x0 0x7e730000 0x0 0x1000>;
+ enable-bit-index = <1>;
+ };
+
+ pmucmc@7e810000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e810000 0x0 0x1000>;
+ enable-bit-index = <0>;
+ };
+
+ pmucmc@7e850000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e850000 0x0 0x1000>;
+ enable-bit-index = <1>;
+ };
+
+ pmucmc@7e890000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e890000 0x0 0x1000>;
+ enable-bit-index = <2>;
+ };
+
+ pmucmc@7e8d0000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e8d0000 0x0 0x1000>;
+ enable-bit-index = <3>;
+ };
+ };
--
1.9.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-22 18:06 [PATCH v4 0/4] perf: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 1/4] MAINTAINERS: Add entry for APM X-Gene SoC PMU driver Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 2/4] Documentation: Add documentation for APM X-Gene SoC PMU DTS binding Tai Nguyen
@ 2016-06-22 18:06 ` Tai Nguyen
2016-06-23 14:32 ` Mark Rutland
2016-06-22 18:06 ` [PATCH v4 4/4] arm64: dts: apm: Add APM X-Gene SoC PMU DTS entries Tai Nguyen
3 siblings, 1 reply; 15+ messages in thread
From: Tai Nguyen @ 2016-06-22 18:06 UTC (permalink / raw)
To: mark.rutland, will.deacon, catalin.marinas
Cc: linux-kernel, devicetree, linux-arm-kernel, patches, Tai Nguyen
Signed-off-by: Tai Nguyen <ttnguyen@apm.com>
---
Documentation/perf/xgene-pmu.txt | 48 ++
drivers/perf/Kconfig | 7 +
drivers/perf/Makefile | 1 +
drivers/perf/xgene_pmu.c | 1437 ++++++++++++++++++++++++++++++++++++++
4 files changed, 1493 insertions(+)
create mode 100644 Documentation/perf/xgene-pmu.txt
create mode 100644 drivers/perf/xgene_pmu.c
diff --git a/Documentation/perf/xgene-pmu.txt b/Documentation/perf/xgene-pmu.txt
new file mode 100644
index 0000000..09c9316
--- /dev/null
+++ b/Documentation/perf/xgene-pmu.txt
@@ -0,0 +1,48 @@
+APM X-Gene SoC Performance Monitoring Unit (PMU)
+================================================
+
+X-Gene SoC PMU consists of various independent system device PMUs such as
+L3 cache(s), I/O bridge(s), memory controller bridge(s) and memory
+controller(s). These PMU devices are loosely architected to follow the
+same model as the PMU for ARM cores. The PMUs share the same top level
+interrupt and status CSR region.
+
+PMU (perf) driver
+-----------------
+
+The xgene-pmu driver registers several perf PMU drivers. Each of the perf
+driver provides description of its available events and configuration options
+in sysfs, see /sys/devices/<l3cX/iobX/mcbX/mcX>/.
+
+The "format" directory describes format of the config (event ID),
+config1 (agent ID) fields of the perf_event_attr structure. The "events"
+directory provides configuration templates for all supported event types that
+can be used with perf tool. For example, "l3c0/bank-fifo-full/" is an
+equivalent of "l3c0/config=0x0b/".
+
+Most of the SoC PMU has a specific list of agent ID used for monitoring
+performance of a specific datapath. For example, agents of a L3 cache can be
+a specific CPU or an I/O bridge. Each PMU has a set of 2 registers capable of
+masking the agents from which the request come from. If the bit with
+the bit number corresponding to the agent is set, the event is counted only if
+it is caused by a request from that agent. Each agent ID bit is mapping to a
+corresponding bit in "config1" fields. By default, the event will be counted
+for all agent requests (config1 = 0xffffffffffffffffULL). For all the supported
+agents of each PMU, please refer to APM X-Gene User Manual.
+
+Each perf driver also provides a "cpumask" sysfs attribute, which contains a
+single CPU ID of the processor which will be used to handle all the PMU events.
+
+Example for perf tool use:
+
+ / # perf list | grep -e l3c -e iob -e mcb -e mc
+ l3c0/ackq-full/ [Kernel PMU event]
+ <...>
+ mcb1/mcb-csw-stall/ [Kernel PMU event]
+
+ / # perf stat -a -e l3c0/read-miss/,mcb1/csw-write-request/ sleep 1
+
+ / # perf stat -a -e l3c0/read-miss,config1=0x01/ sleep 1
+
+The driver does not support sampling, therefore "perf record" will
+not work. Per-task (without "-a") perf sessions are not supported.
diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
index 04e2653..be597dd 100644
--- a/drivers/perf/Kconfig
+++ b/drivers/perf/Kconfig
@@ -12,4 +12,11 @@ config ARM_PMU
Say y if you want to use CPU performance monitors on ARM-based
systems.
+config XGENE_PMU
+ depends on PERF_EVENTS && ARCH_XGENE
+ bool "APM SoC X-Gene PMU"
+ default n
+ help
+ Say y if you want to use APM X-Gene SOC performance monitors.
+
endmenu
diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
index acd2397..b116e98 100644
--- a/drivers/perf/Makefile
+++ b/drivers/perf/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_ARM_PMU) += arm_pmu.o
+obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o
diff --git a/drivers/perf/xgene_pmu.c b/drivers/perf/xgene_pmu.c
new file mode 100644
index 0000000..5a3c147
--- /dev/null
+++ b/drivers/perf/xgene_pmu.c
@@ -0,0 +1,1437 @@
+/*
+ * APM X-Gene SoC PMU (Performance Monitor Unit)
+ *
+ * Copyright (c) 2016, Applied Micro Circuits Corporation
+ * Author: Hoan Tran <hotran@apm.com>
+ * Tai Nguyen <ttnguyen@apm.com>
+ *
+ * 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.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/acpi.h>
+#include <linux/clk.h>
+#include <linux/cpumask.h>
+#include <linux/efi.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_fdt.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#define CSW_CSWCR 0x0000
+#define CSW_CSWCR_DUALMCB_MASK BIT(0)
+#define MCBADDRMR 0x0000
+#define MCBADDRMR_DUALMCU_MODE_MASK BIT(2)
+
+#define PCPPMU_INTSTATUS_REG 0x000
+#define PCPPMU_INTMASK_REG 0x004
+#define PCPPMU_INTMASK 0x0000000F
+#define PCPPMU_INTENMASK 0xFFFFFFFF
+#define PCPPMU_INTCLRMASK 0xFFFFFFF0
+#define PCPPMU_INT_MCU BIT(0)
+#define PCPPMU_INT_MCB BIT(1)
+#define PCPPMU_INT_L3C BIT(2)
+#define PCPPMU_INT_IOB BIT(3)
+
+#define PMU_MAX_COUNTERS 4
+#define PMU_CNT_MAX_VAL 0x100000000ULL
+#define PMU_OVERFLOW_MASK 0xF
+#define PMU_PMCR_E BIT(0)
+#define PMU_PMCR_P BIT(1)
+
+#define PMU_PMEVCNTR0 0x000
+#define PMU_PMEVCNTR1 0x004
+#define PMU_PMEVCNTR2 0x008
+#define PMU_PMEVCNTR3 0x00C
+#define PMU_PMEVTYPER0 0x400
+#define PMU_PMEVTYPER1 0x404
+#define PMU_PMEVTYPER2 0x408
+#define PMU_PMEVTYPER3 0x40C
+#define PMU_PMAMR0 0xA00
+#define PMU_PMAMR1 0xA04
+#define PMU_PMCNTENSET 0xC00
+#define PMU_PMCNTENCLR 0xC20
+#define PMU_PMINTENSET 0xC40
+#define PMU_PMINTENCLR 0xC60
+#define PMU_PMOVSR 0xC80
+#define PMU_PMCR 0xE04
+
+#define to_pmu_dev(p) container_of(p, struct xgene_pmu_dev, pmu)
+#define _GET_CNTR(ev) (ev->hw.extra_reg.reg)
+#define _GET_EVENTID(ev) (ev->hw.config & 0xFFULL)
+#define _GET_AGENTID(ev) (ev->hw.extra_reg.config & 0xFFFFFFFFULL)
+#define _GET_AGENT1ID(ev) ((ev->hw.extra_reg.config >> 32) & 0xFFFFFFFFULL)
+
+struct hw_pmu_info {
+ u32 type;
+ u32 enable_mask;
+ void __iomem *csr;
+};
+
+struct xgene_pmu_dev {
+ struct hw_pmu_info *inf;
+ struct xgene_pmu *parent;
+ struct pmu pmu;
+ u8 max_counters;
+ DECLARE_BITMAP(cntr_assign_mask, PMU_MAX_COUNTERS);
+ raw_spinlock_t lock;
+ u64 max_period;
+ const struct attribute_group **attr_groups;
+ struct perf_event *pmu_counter_event[4];
+};
+
+struct xgene_pmu {
+ struct device *dev;
+ int version;
+ void __iomem *pcppmu_csr;
+ u32 mcb_active_mask;
+ u32 mc_active_mask;
+ cpumask_t cpu;
+ struct list_head l3cpmus;
+ struct list_head iobpmus;
+ struct list_head mcbpmus;
+ struct list_head mcpmus;
+};
+
+struct xgene_pmu_dev_ctx {
+ char *name;
+ struct list_head next;
+ struct xgene_pmu_dev *pmu_dev;
+ struct hw_pmu_info inf;
+};
+
+struct xgene_pmu_event {
+ struct device_attribute attr;
+ u32 config;
+};
+
+struct xgene_pmu_data {
+ int id;
+ u32 data;
+};
+
+enum xgene_pmu_version {
+ PCP_PMU_V1 = 1,
+ PCP_PMU_V2,
+};
+
+enum xgene_pmu_dev_type {
+ PMU_TYPE_L3C = 0,
+ PMU_TYPE_IOB,
+ PMU_TYPE_MCB,
+ PMU_TYPE_MC,
+};
+
+/*
+ * sysfs format attributes
+ */
+static ssize_t xgene_pmu_format_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dev_ext_attribute *eattr;
+
+ eattr = container_of(attr, struct dev_ext_attribute, attr);
+ return sprintf(buf, "%s\n", (char *) eattr->var);
+}
+
+#define XGENE_PMU_FORMAT_ATTR(_name, _config) \
+ struct dev_ext_attribute pmu_format_attr_##_name = \
+ { __ATTR(_name, S_IRUGO, xgene_pmu_format_show, NULL), _config }
+
+static XGENE_PMU_FORMAT_ATTR(l3c_eventid, "config:0-7");
+static XGENE_PMU_FORMAT_ATTR(l3c_agentid, "config1:0-9");
+static XGENE_PMU_FORMAT_ATTR(iob_eventid, "config:0-7");
+static XGENE_PMU_FORMAT_ATTR(iob_agentid, "config1:0-63");
+static XGENE_PMU_FORMAT_ATTR(mcb_eventid, "config:0-5");
+static XGENE_PMU_FORMAT_ATTR(mcb_agentid, "config1:0-9");
+static XGENE_PMU_FORMAT_ATTR(mc_eventid, "config:0-28");
+
+static const struct attribute *l3c_pmu_format_attrs[] = {
+ &pmu_format_attr_l3c_eventid.attr.attr,
+ &pmu_format_attr_l3c_agentid.attr.attr,
+ NULL,
+};
+
+static const struct attribute *iob_pmu_format_attrs[] = {
+ &pmu_format_attr_iob_eventid.attr.attr,
+ &pmu_format_attr_iob_agentid.attr.attr,
+ NULL,
+};
+
+static const struct attribute *mcb_pmu_format_attrs[] = {
+ &pmu_format_attr_mcb_eventid.attr.attr,
+ &pmu_format_attr_mcb_agentid.attr.attr,
+ NULL,
+};
+
+static const struct attribute *mc_pmu_format_attrs[] = {
+ &pmu_format_attr_mc_eventid.attr.attr,
+ NULL,
+};
+
+static const struct attribute_group l3c_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = (struct attribute **) l3c_pmu_format_attrs,
+};
+
+static const struct attribute_group iob_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = (struct attribute **) iob_pmu_format_attrs,
+};
+
+static const struct attribute_group mcb_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = (struct attribute **) mcb_pmu_format_attrs,
+};
+
+static const struct attribute_group mc_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = (struct attribute **) mc_pmu_format_attrs,
+};
+
+/*
+ * sysfs event attributes
+ */
+static ssize_t xgene_pmu_event_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct xgene_pmu_event *event = container_of(attr,
+ struct xgene_pmu_event, attr);
+
+ return sprintf(buf, "config=0x%x\n", event->config);
+}
+
+#define XGENE_PMU_EVENT_ATTR(_name) \
+ __ATTR(_name, S_IRUGO, xgene_pmu_event_show, NULL)
+#define XGENE_PMU_EVENT(_name, _config) { \
+ .attr = XGENE_PMU_EVENT_ATTR(_name), \
+ .config = _config, }
+
+static const struct xgene_pmu_event l3c_pmu_events[] = {
+ XGENE_PMU_EVENT(cycle-count, 0x00),
+ XGENE_PMU_EVENT(cycle-count-div-64, 0x01),
+ XGENE_PMU_EVENT(read-hit, 0x02),
+ XGENE_PMU_EVENT(read-miss, 0x03),
+ XGENE_PMU_EVENT(write-need-replacement, 0x06),
+ XGENE_PMU_EVENT(write-not-need-replacement, 0x07),
+ XGENE_PMU_EVENT(tq-full, 0x08),
+ XGENE_PMU_EVENT(ackq-full, 0x09),
+ XGENE_PMU_EVENT(wdb-full, 0x0a),
+ XGENE_PMU_EVENT(bank-fifo-full, 0x0b),
+ XGENE_PMU_EVENT(odb-full, 0x0c),
+ XGENE_PMU_EVENT(wbq-full, 0x0d),
+ XGENE_PMU_EVENT(bank-conflict-fifo-issue, 0x0e),
+ XGENE_PMU_EVENT(bank-fifo-issue, 0x0f),
+};
+
+static const struct xgene_pmu_event iob_pmu_events[] = {
+ XGENE_PMU_EVENT(cycle-count, 0x00),
+ XGENE_PMU_EVENT(cycle-count-div-64, 0x01),
+ XGENE_PMU_EVENT(axi0-read, 0x02),
+ XGENE_PMU_EVENT(axi0-read-partial, 0x03),
+ XGENE_PMU_EVENT(axi1-read, 0x04),
+ XGENE_PMU_EVENT(axi1-read-partial, 0x05),
+ XGENE_PMU_EVENT(csw-read-block, 0x06),
+ XGENE_PMU_EVENT(csw-read-partial, 0x07),
+ XGENE_PMU_EVENT(axi0-write, 0x10),
+ XGENE_PMU_EVENT(axi0-write-partial, 0x11),
+ XGENE_PMU_EVENT(axi1-write, 0x13),
+ XGENE_PMU_EVENT(axi1-write-partial, 0x14),
+ XGENE_PMU_EVENT(csw-inbound-dirty, 0x16),
+};
+
+static const struct xgene_pmu_event mcb_pmu_events[] = {
+ XGENE_PMU_EVENT(cycle-count, 0x00),
+ XGENE_PMU_EVENT(cycle-count-div-64, 0x01),
+ XGENE_PMU_EVENT(csw-read, 0x02),
+ XGENE_PMU_EVENT(csw-write-request, 0x03),
+ XGENE_PMU_EVENT(mcb-csw-stall, 0x04),
+ XGENE_PMU_EVENT(cancel-read-gack, 0x05),
+};
+
+static const struct xgene_pmu_event mc_pmu_events[] = {
+ XGENE_PMU_EVENT(cycle-count, 0x00),
+ XGENE_PMU_EVENT(cycle-count-div-64, 0x01),
+ XGENE_PMU_EVENT(act-cmd-sent, 0x02),
+ XGENE_PMU_EVENT(pre-cmd-sent, 0x03),
+ XGENE_PMU_EVENT(rd-cmd-sent, 0x04),
+ XGENE_PMU_EVENT(rda-cmd-sent, 0x05),
+ XGENE_PMU_EVENT(wr-cmd-sent, 0x06),
+ XGENE_PMU_EVENT(wra-cmd-sent, 0x07),
+ XGENE_PMU_EVENT(pde-cmd-sent, 0x08),
+ XGENE_PMU_EVENT(sre-cmd-sent, 0x09),
+ XGENE_PMU_EVENT(prea-cmd-sent, 0x0a),
+ XGENE_PMU_EVENT(ref-cmd-sent, 0x0b),
+ XGENE_PMU_EVENT(rd-rda-cmd-sent, 0x0c),
+ XGENE_PMU_EVENT(wr-wra-cmd-sent, 0x0d),
+ XGENE_PMU_EVENT(in-rd-collision, 0x0e),
+ XGENE_PMU_EVENT(in-wr-collision, 0x0f),
+ XGENE_PMU_EVENT(collision-queue-not-empty, 0x10),
+ XGENE_PMU_EVENT(collision-queue-full, 0x11),
+ XGENE_PMU_EVENT(mcu-request, 0x12),
+ XGENE_PMU_EVENT(mcu-rd-request, 0x13),
+ XGENE_PMU_EVENT(mcu-hp-rd-request, 0x14),
+ XGENE_PMU_EVENT(mcu-wr-request, 0x15),
+ XGENE_PMU_EVENT(mcu-rd-proceed-all, 0x16),
+ XGENE_PMU_EVENT(mcu-rd-proceed-cancel, 0x17),
+ XGENE_PMU_EVENT(mcu-rd-response, 0x18),
+ XGENE_PMU_EVENT(mcu-rd-proceed-speculative-all, 0x19),
+ XGENE_PMU_EVENT(mcu-rd-proceed-speculative-cancel, 0x1a),
+ XGENE_PMU_EVENT(mcu-wr-proceed-all, 0x1b),
+ XGENE_PMU_EVENT(mcu-wr-proceed-cancel, 0x1c),
+};
+
+/* Populated in xgene_pmu_probe */
+static struct attribute *l3c_pmu_events_attrs[ARRAY_SIZE(l3c_pmu_events) + 1];
+static struct attribute *iob_pmu_events_attrs[ARRAY_SIZE(iob_pmu_events) + 1];
+static struct attribute *mcb_pmu_events_attrs[ARRAY_SIZE(mcb_pmu_events) + 1];
+static struct attribute *mc_pmu_events_attrs[ARRAY_SIZE(mc_pmu_events) + 1];
+
+static const struct attribute_group l3c_pmu_events_attr_group = {
+ .name = "events",
+ .attrs = l3c_pmu_events_attrs,
+};
+
+static const struct attribute_group iob_pmu_events_attr_group = {
+ .name = "events",
+ .attrs = iob_pmu_events_attrs,
+};
+
+static const struct attribute_group mcb_pmu_events_attr_group = {
+ .name = "events",
+ .attrs = mcb_pmu_events_attrs,
+};
+
+static const struct attribute_group mc_pmu_events_attr_group = {
+ .name = "events",
+ .attrs = mc_pmu_events_attrs,
+};
+
+/*
+ * sysfs cpumask attributes
+ */
+static ssize_t xgene_pmu_cpumask_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(dev_get_drvdata(dev));
+
+ return cpumap_print_to_pagebuf(true, buf, &pmu_dev->parent->cpu);
+}
+
+static DEVICE_ATTR(cpumask, S_IRUGO, xgene_pmu_cpumask_show, NULL);
+
+static const struct attribute *xgene_pmu_cpumask_attrs[] = {
+ &dev_attr_cpumask.attr,
+ NULL,
+};
+
+static const struct attribute_group pmu_cpumask_attr_group = {
+ .attrs = (struct attribute **) xgene_pmu_cpumask_attrs,
+};
+
+/*
+ * Per PMU device attribute groups
+ */
+static const struct attribute_group *l3c_pmu_attr_groups[] = {
+ &l3c_pmu_format_attr_group,
+ &pmu_cpumask_attr_group,
+ &l3c_pmu_events_attr_group,
+ NULL
+};
+
+static const struct attribute_group *iob_pmu_attr_groups[] = {
+ &iob_pmu_format_attr_group,
+ &pmu_cpumask_attr_group,
+ &iob_pmu_events_attr_group,
+ NULL
+};
+
+static const struct attribute_group *mcb_pmu_attr_groups[] = {
+ &mcb_pmu_format_attr_group,
+ &pmu_cpumask_attr_group,
+ &mcb_pmu_events_attr_group,
+ NULL
+};
+
+static const struct attribute_group *mc_pmu_attr_groups[] = {
+ &mc_pmu_format_attr_group,
+ &pmu_cpumask_attr_group,
+ &mc_pmu_events_attr_group,
+ NULL
+};
+
+static int get_next_avail_cntr(struct xgene_pmu_dev *pmu_dev)
+{
+ int cntr;
+
+ cntr = find_first_zero_bit(pmu_dev->cntr_assign_mask,
+ pmu_dev->max_counters);
+ if (cntr == pmu_dev->max_counters)
+ return -ENOSPC;
+ set_bit(cntr, pmu_dev->cntr_assign_mask);
+
+ return cntr;
+}
+
+static void clear_avail_cntr(struct xgene_pmu_dev *pmu_dev, int cntr)
+{
+ clear_bit(cntr, pmu_dev->cntr_assign_mask);
+}
+
+static inline void xgene_pmu_mask_int(struct xgene_pmu *xgene_pmu)
+{
+ writel(PCPPMU_INTENMASK, xgene_pmu->pcppmu_csr + PCPPMU_INTMASK_REG);
+}
+
+static inline void xgene_pmu_unmask_int(struct xgene_pmu *xgene_pmu)
+{
+ writel(PCPPMU_INTCLRMASK, xgene_pmu->pcppmu_csr + PCPPMU_INTMASK_REG);
+}
+
+static inline u32 xgene_pmu_read_counter(struct xgene_pmu_dev *pmu_dev, int idx)
+{
+ return readl(pmu_dev->inf->csr + PMU_PMEVCNTR0 + (4 * idx));
+}
+
+static inline void
+xgene_pmu_write_counter(struct xgene_pmu_dev *pmu_dev, int idx, u32 val)
+{
+ writel(val, pmu_dev->inf->csr + PMU_PMEVCNTR0 + (4 * idx));
+}
+
+static inline void
+xgene_pmu_write_evttype(struct xgene_pmu_dev *pmu_dev, int idx, u32 val)
+{
+ writel(val, pmu_dev->inf->csr + PMU_PMEVTYPER0 + (4 * idx));
+}
+
+static inline void
+xgene_pmu_write_agenttype(struct xgene_pmu_dev *pmu_dev, u32 val)
+{
+ writel(val, pmu_dev->inf->csr + PMU_PMAMR0);
+}
+
+static inline void
+xgene_pmu_write_agent1type(struct xgene_pmu_dev *pmu_dev, u32 val)
+{
+ writel(val, pmu_dev->inf->csr + PMU_PMAMR1);
+}
+
+static inline void
+xgene_pmu_enable_counter(struct xgene_pmu_dev *pmu_dev, int idx)
+{
+ u32 val;
+
+ val = readl(pmu_dev->inf->csr + PMU_PMCNTENSET);
+ val |= 1 << idx;
+ writel(val, pmu_dev->inf->csr + PMU_PMCNTENSET);
+}
+
+static inline void
+xgene_pmu_disable_counter(struct xgene_pmu_dev *pmu_dev, int idx)
+{
+ u32 val;
+
+ val = readl(pmu_dev->inf->csr + PMU_PMCNTENCLR);
+ val |= 1 << idx;
+ writel(val, pmu_dev->inf->csr + PMU_PMCNTENCLR);
+}
+
+static inline void
+xgene_pmu_enable_counter_int(struct xgene_pmu_dev *pmu_dev, int idx)
+{
+ u32 val;
+
+ val = readl(pmu_dev->inf->csr + PMU_PMINTENSET);
+ val |= 1 << idx;
+ writel(val, pmu_dev->inf->csr + PMU_PMINTENSET);
+}
+
+static inline void
+xgene_pmu_disable_counter_int(struct xgene_pmu_dev *pmu_dev, int idx)
+{
+ u32 val;
+
+ val = readl(pmu_dev->inf->csr + PMU_PMINTENCLR);
+ val |= 1 << idx;
+ writel(val, pmu_dev->inf->csr + PMU_PMINTENCLR);
+}
+
+static inline void xgene_pmu_reset_counters(struct xgene_pmu_dev *pmu_dev)
+{
+ u32 val;
+
+ val = readl(pmu_dev->inf->csr + PMU_PMCR);
+ val |= PMU_PMCR_P;
+ writel(val, pmu_dev->inf->csr + PMU_PMCR);
+}
+
+static inline void xgene_pmu_start_counters(struct xgene_pmu_dev *pmu_dev)
+{
+ u32 val;
+
+ val = readl(pmu_dev->inf->csr + PMU_PMCR);
+ val |= PMU_PMCR_E;
+ writel(val, pmu_dev->inf->csr + PMU_PMCR);
+}
+
+static inline void xgene_pmu_stop_counters(struct xgene_pmu_dev *pmu_dev)
+{
+ u32 val;
+
+ val = readl(pmu_dev->inf->csr + PMU_PMCR);
+ val &= ~PMU_PMCR_E;
+ writel(val, pmu_dev->inf->csr + PMU_PMCR);
+}
+
+static int xgene_perf_event_init(struct perf_event *event)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ u64 config, config1;
+
+ /* Test the event attr type check for PMU enumeration */
+ if (event->attr.type != event->pmu->type)
+ return -ENOENT;
+
+ /*
+ * SOC PMU counters are shared across all cores.
+ * Therefore, it does not support per-process mode.
+ * Also, it does not support event sampling mode.
+ */
+ if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
+ return -EINVAL;
+
+ /* SOC counters do not have usr/os/guest/host bits */
+ if (event->attr.exclude_user || event->attr.exclude_kernel ||
+ event->attr.exclude_host || event->attr.exclude_guest)
+ return -EINVAL;
+
+ if (event->cpu < 0)
+ return -EINVAL;
+ /*
+ * Many perf core operations (eg. events rotation) operate on a
+ * single CPU context. This is obvious for CPU PMUs, where one
+ * expects the same sets of events being observed on all CPUs,
+ * but can lead to issues for off-core PMUs, where each
+ * event could be theoretically assigned to a different CPU. To
+ * mitigate this, we enforce CPU assignment to one, selected
+ * processor (the one described in the "cpumask" attribute).
+ */
+ event->cpu = cpumask_first(&pmu_dev->parent->cpu);
+
+ config = event->attr.config;
+ config1 = event->attr.config1;
+
+ hwc->config = config;
+ /*
+ * Each bit of the config1 field represents an agent from which the
+ * request of the event come. The event is counted only if it's caused
+ * by a request of an agent has the bit set.
+ * By default, the event is counted for all agents.
+ */
+ if (config1)
+ hwc->extra_reg.config = config1;
+ else
+ hwc->extra_reg.config = 0xFFFFFFFFFFFFFFFFULL;
+
+ return 0;
+}
+
+static void xgene_perf_enable_event(struct perf_event *event)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+
+ xgene_pmu_write_evttype(pmu_dev, _GET_CNTR(event), _GET_EVENTID(event));
+ xgene_pmu_write_agenttype(pmu_dev, _GET_AGENTID(event));
+ if (pmu_dev->inf->type == PMU_TYPE_IOB)
+ xgene_pmu_write_agent1type(pmu_dev, _GET_AGENT1ID(event));
+
+ xgene_pmu_start_counters(pmu_dev);
+ xgene_pmu_enable_counter(pmu_dev, _GET_CNTR(event));
+ xgene_pmu_enable_counter_int(pmu_dev, _GET_CNTR(event));
+}
+
+static void xgene_perf_disable_event(struct perf_event *event)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+
+ xgene_pmu_disable_counter(pmu_dev, _GET_CNTR(event));
+ xgene_pmu_disable_counter_int(pmu_dev, _GET_CNTR(event));
+}
+
+static void xgene_perf_start(struct perf_event *event, int flags)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+
+ if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
+ return;
+
+ WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
+ hwc->state = 0;
+
+ if (flags & PERF_EF_RELOAD) {
+ u64 prev_raw_count = local64_read(&hwc->prev_count);
+
+ xgene_pmu_write_counter(pmu_dev, _GET_CNTR(event),
+ (u32) prev_raw_count);
+ }
+
+ xgene_perf_enable_event(event);
+ perf_event_update_userpage(event);
+}
+
+static void xgene_perf_read(struct perf_event *event)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ u64 prev_raw_count;
+ u64 count;
+ u64 delta;
+
+ count = xgene_pmu_read_counter(pmu_dev, _GET_CNTR(event))
+ & pmu_dev->max_period;
+
+ prev_raw_count = local64_read(&hwc->prev_count);
+ if (local64_cmpxchg(&hwc->prev_count, prev_raw_count, count) !=
+ prev_raw_count)
+ return;
+
+ delta = (count - prev_raw_count) & pmu_dev->max_period;
+
+ local64_add(delta, &event->count);
+}
+
+static void xgene_perf_stop(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ u64 config;
+
+ if (hwc->state & PERF_HES_UPTODATE)
+ return;
+
+ xgene_perf_disable_event(event);
+ WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+ hwc->state |= PERF_HES_STOPPED;
+
+ if (hwc->state & PERF_HES_UPTODATE)
+ return;
+
+ config = hwc->config;
+ xgene_perf_read(event);
+ hwc->state |= PERF_HES_UPTODATE;
+}
+
+static int xgene_perf_add(struct perf_event *event, int flags)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+
+ event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+
+ /* Allocate an event counter */
+ hw->idx = get_next_avail_cntr(pmu_dev);
+ if (hw->idx < 0)
+ return -EAGAIN;
+
+ event->hw.extra_reg.reg = (u16) hw->idx;
+
+ if (flags & PERF_EF_START)
+ xgene_perf_start(event, PERF_EF_RELOAD);
+
+ /* Update counter event pointer for Interrupt handler */
+ pmu_dev->pmu_counter_event[hw->idx] = event;
+
+ return 0;
+}
+
+static void xgene_perf_del(struct perf_event *event, int flags)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+
+ xgene_perf_stop(event, PERF_EF_UPDATE);
+
+ /* clear the assigned counter */
+ clear_avail_cntr(pmu_dev, _GET_CNTR(event));
+
+ perf_event_update_userpage(event);
+}
+
+static u64 xgene_perf_event_update(struct perf_event *event)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ u64 delta, prev_raw_count, new_raw_count;
+
+again:
+ prev_raw_count = local64_read(&hwc->prev_count);
+ new_raw_count = pmu_dev->max_period;
+
+ if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
+ new_raw_count) != prev_raw_count)
+ goto again;
+
+ delta = (new_raw_count - prev_raw_count) & pmu_dev->max_period;
+
+ local64_add(delta, &event->count);
+ local64_sub(delta, &hwc->period_left);
+
+ return new_raw_count;
+}
+
+static int xgene_perf_event_set_period(struct perf_event *event)
+{
+ struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ s64 left = local64_read(&hwc->period_left);
+ s64 period = hwc->sample_period;
+ int ret = 0;
+
+ if (unlikely(left <= -period)) {
+ left = period;
+ local64_set(&hwc->period_left, left);
+ hwc->last_period = period;
+ ret = 1;
+ }
+
+ if (unlikely(left <= 0)) {
+ left += period;
+ local64_set(&hwc->period_left, left);
+ hwc->last_period = period;
+ ret = 1;
+ }
+
+ /*
+ * Limit the maximum period to prevent the counter value
+ * from overtaking the one we are about to program. In
+ * effect we are reducing max_period to account for
+ * interrupt latency (and we are being very conservative).
+ */
+ if (left > (pmu_dev->max_period >> 1))
+ left = pmu_dev->max_period >> 1;
+
+ local64_set(&hwc->prev_count, (u64) -left);
+
+ xgene_pmu_write_counter(pmu_dev, hwc->idx, (u64)(-left) & 0xffffffff);
+
+ perf_event_update_userpage(event);
+
+ return ret;
+}
+
+static int xgene_init_perf(struct xgene_pmu_dev *pmu_dev, char *name)
+{
+ struct xgene_pmu *xgene_pmu;
+
+ raw_spin_lock_init(&pmu_dev->lock);
+
+ pmu_dev->max_period = PMU_CNT_MAX_VAL - 1;
+ /* First PMU version supports only single event counter */
+ xgene_pmu = pmu_dev->parent;
+ if (xgene_pmu->version == PCP_PMU_V1)
+ pmu_dev->max_counters = 1;
+ else
+ pmu_dev->max_counters = PMU_MAX_COUNTERS;
+
+ /* Perf driver registration */
+ pmu_dev->pmu = (struct pmu) {
+ .attr_groups = pmu_dev->attr_groups,
+ .task_ctx_nr = perf_invalid_context,
+ .event_init = xgene_perf_event_init,
+ .add = xgene_perf_add,
+ .del = xgene_perf_del,
+ .start = xgene_perf_start,
+ .stop = xgene_perf_stop,
+ .read = xgene_perf_read,
+ };
+
+ /* Hardware counter init */
+ xgene_pmu_stop_counters(pmu_dev);
+ xgene_pmu_reset_counters(pmu_dev);
+
+ return perf_pmu_register(&pmu_dev->pmu, name, -1);
+}
+
+static int
+xgene_pmu_dev_add(struct xgene_pmu *xgene_pmu, struct xgene_pmu_dev_ctx *ctx)
+{
+ struct device *dev = xgene_pmu->dev;
+ struct xgene_pmu_dev *pmu;
+ int rc;
+
+ pmu = devm_kzalloc(dev, sizeof(*pmu), GFP_KERNEL);
+ if (!pmu)
+ return -ENOMEM;
+ pmu->parent = xgene_pmu;
+ pmu->inf = &ctx->inf;
+ ctx->pmu_dev = pmu;
+
+ switch (pmu->inf->type) {
+ case PMU_TYPE_L3C:
+ pmu->attr_groups = l3c_pmu_attr_groups;
+ break;
+ case PMU_TYPE_IOB:
+ pmu->attr_groups = iob_pmu_attr_groups;
+ break;
+ case PMU_TYPE_MCB:
+ if (!(xgene_pmu->mcb_active_mask & pmu->inf->enable_mask))
+ goto dev_err;
+ pmu->attr_groups = mcb_pmu_attr_groups;
+ break;
+ case PMU_TYPE_MC:
+ if (!(xgene_pmu->mc_active_mask & pmu->inf->enable_mask))
+ goto dev_err;
+ pmu->attr_groups = mc_pmu_attr_groups;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ rc = xgene_init_perf(pmu, ctx->name);
+ if (rc) {
+ dev_err(dev, "%s PMU: Failed to init perf driver\n", ctx->name);
+ goto dev_err;
+ }
+
+ dev_info(dev, "%s PMU registered\n", ctx->name);
+
+ return rc;
+
+dev_err:
+ devm_kfree(dev, pmu);
+ return -ENODEV;
+}
+
+static irqreturn_t _xgene_pmu_isr(int irq, struct xgene_pmu_dev *pmu_dev)
+{
+ struct xgene_pmu *xgene_pmu = pmu_dev->parent;
+ u32 pmovsr;
+ int idx;
+
+ pmovsr = readl(pmu_dev->inf->csr + PMU_PMOVSR) & PMU_OVERFLOW_MASK;
+ /* Clear interrupt flag */
+ if (xgene_pmu->version == PCP_PMU_V1)
+ writel(0x0, pmu_dev->inf->csr + PMU_PMOVSR);
+ else
+ writel(pmovsr, pmu_dev->inf->csr + PMU_PMOVSR);
+
+ if (!pmovsr)
+ return IRQ_NONE;
+
+ for (idx = 0; idx < PMU_MAX_COUNTERS; idx++) {
+ struct perf_event *event = pmu_dev->pmu_counter_event[idx];
+ int overflowed = pmovsr & BIT(idx);
+
+ /* Ignore if we don't have an event. */
+ if (!event || !overflowed)
+ continue;
+ xgene_perf_event_update(event);
+ xgene_perf_event_set_period(event);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
+{
+ struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
+ struct xgene_pmu *xgene_pmu = dev_id;
+ u32 val;
+
+ xgene_pmu_mask_int(xgene_pmu);
+
+ /* Get Interrupt PMU source */
+ val = readl(xgene_pmu->pcppmu_csr + PCPPMU_INTSTATUS_REG)
+ & PCPPMU_INTMASK;
+ if (val & PCPPMU_INT_MCU) {
+ list_for_each_entry_safe(ctx, temp_ctx,
+ &xgene_pmu->mcpmus, next) {
+ _xgene_pmu_isr(irq, ctx->pmu_dev);
+ }
+ }
+ if (val & PCPPMU_INT_MCB) {
+ list_for_each_entry_safe(ctx, temp_ctx,
+ &xgene_pmu->mcbpmus, next) {
+ _xgene_pmu_isr(irq, ctx->pmu_dev);
+ }
+ }
+ if (val & PCPPMU_INT_L3C) {
+ list_for_each_entry_safe(ctx, temp_ctx,
+ &xgene_pmu->l3cpmus, next) {
+ _xgene_pmu_isr(irq, ctx->pmu_dev);
+ }
+ }
+ if (val & PCPPMU_INT_IOB) {
+ list_for_each_entry_safe(ctx, temp_ctx,
+ &xgene_pmu->iobpmus, next) {
+ _xgene_pmu_isr(irq, ctx->pmu_dev);
+ }
+ }
+
+ xgene_pmu_unmask_int(xgene_pmu);
+
+ return IRQ_HANDLED;
+}
+
+static int acpi_pmu_probe_active_mcb_mcu(struct xgene_pmu *xgene_pmu,
+ struct platform_device *pdev)
+{
+ void __iomem *csw_csr, *mcba_csr, *mcbb_csr;
+ struct resource *res;
+ unsigned int reg;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ csw_csr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(csw_csr)) {
+ dev_err(&pdev->dev, "ioremap failed for CSW CSR resource\n");
+ return PTR_ERR(csw_csr);
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+ mcba_csr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(mcba_csr)) {
+ dev_err(&pdev->dev, "ioremap failed for MCBA CSR resource\n");
+ return PTR_ERR(mcba_csr);
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+ mcbb_csr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(mcbb_csr)) {
+ dev_err(&pdev->dev, "ioremap failed for MCBB CSR resource\n");
+ return PTR_ERR(mcbb_csr);
+ }
+
+ reg = readl(csw_csr + CSW_CSWCR);
+ if (reg & CSW_CSWCR_DUALMCB_MASK) {
+ /* Dual MCB active */
+ xgene_pmu->mcb_active_mask = 0x3;
+ /* Probe all active MC(s) */
+ reg = readl(mcbb_csr + CSW_CSWCR);
+ xgene_pmu->mc_active_mask =
+ (reg & MCBADDRMR_DUALMCU_MODE_MASK) ? 0xF : 0x5;
+ } else {
+ /* Single MCB active */
+ xgene_pmu->mcb_active_mask = 0x1;
+ /* Probe all active MC(s) */
+ reg = readl(mcba_csr + CSW_CSWCR);
+ xgene_pmu->mc_active_mask =
+ (reg & MCBADDRMR_DUALMCU_MODE_MASK) ? 0x3 : 0x1;
+ }
+
+ return 0;
+}
+
+static int fdt_pmu_probe_active_mcb_mcu(struct xgene_pmu *xgene_pmu,
+ struct platform_device *pdev)
+{
+ struct regmap *csw_map, *mcba_map, *mcbb_map;
+ struct device_node *np = pdev->dev.of_node;
+ unsigned int reg;
+
+ csw_map = syscon_regmap_lookup_by_phandle(np, "regmap-csw");
+ if (IS_ERR(csw_map)) {
+ dev_err(&pdev->dev, "unable to get syscon regmap csw\n");
+ return PTR_ERR(csw_map);
+ }
+
+ mcba_map = syscon_regmap_lookup_by_phandle(np, "regmap-mcba");
+ if (IS_ERR(mcba_map)) {
+ dev_err(&pdev->dev, "unable to get syscon regmap mcba\n");
+ return PTR_ERR(mcba_map);
+ }
+
+ mcbb_map = syscon_regmap_lookup_by_phandle(np, "regmap-mcbb");
+ if (IS_ERR(mcbb_map)) {
+ dev_err(&pdev->dev, "unable to get syscon regmap mcbb\n");
+ return PTR_ERR(mcbb_map);
+ }
+
+ if (regmap_read(csw_map, CSW_CSWCR, ®))
+ return -EINVAL;
+
+ if (reg & CSW_CSWCR_DUALMCB_MASK) {
+ /* Dual MCB active */
+ xgene_pmu->mcb_active_mask = 0x3;
+ /* Probe all active MC(s) */
+ if (regmap_read(mcbb_map, MCBADDRMR, ®))
+ return 0;
+ xgene_pmu->mc_active_mask =
+ (reg & MCBADDRMR_DUALMCU_MODE_MASK) ? 0xF : 0x5;
+ } else {
+ /* Single MCB active */
+ xgene_pmu->mcb_active_mask = 0x1;
+ /* Probe all active MC(s) */
+ if (regmap_read(mcba_map, MCBADDRMR, ®))
+ return 0;
+ xgene_pmu->mc_active_mask =
+ (reg & MCBADDRMR_DUALMCU_MODE_MASK) ? 0x3 : 0x1;
+ }
+
+ return 0;
+}
+
+static int xgene_pmu_probe_active_mcb_mcu(struct xgene_pmu *xgene_pmu,
+ struct platform_device *pdev)
+{
+ if (has_acpi_companion(&pdev->dev))
+ return acpi_pmu_probe_active_mcb_mcu(xgene_pmu, pdev);
+ return fdt_pmu_probe_active_mcb_mcu(xgene_pmu, pdev);
+}
+
+static char *xgene_pmu_dev_name(u32 type, int id)
+{
+ switch (type) {
+ case PMU_TYPE_L3C:
+ return kasprintf(GFP_KERNEL, "l3c%d", id);
+ case PMU_TYPE_IOB:
+ return kasprintf(GFP_KERNEL, "iob%d", id);
+ case PMU_TYPE_MCB:
+ return kasprintf(GFP_KERNEL, "mcb%d", id);
+ case PMU_TYPE_MC:
+ return kasprintf(GFP_KERNEL, "mc%d", id);
+ default:
+ return kasprintf(GFP_KERNEL, "unknown");
+ }
+}
+
+#if defined(CONFIG_ACPI)
+static int acpi_pmu_dev_add_resource(struct acpi_resource *ares, void *data)
+{
+ struct resource *res = data;
+
+ if (ares->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32)
+ acpi_dev_resource_memory(ares, res);
+
+ /* Always tell the ACPI core to skip this resource */
+ return 1;
+}
+
+static struct
+xgene_pmu_dev_ctx *acpi_get_pmu_hw_inf(struct xgene_pmu *xgene_pmu,
+ struct acpi_device *adev, u32 type)
+{
+ struct device *dev = xgene_pmu->dev;
+ struct list_head resource_list;
+ struct xgene_pmu_dev_ctx *ctx;
+ const union acpi_object *obj;
+ struct hw_pmu_info *inf;
+ void __iomem *dev_csr;
+ struct resource res;
+ int enable_bit;
+ int rc;
+
+ ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return NULL;
+
+ INIT_LIST_HEAD(&resource_list);
+ rc = acpi_dev_get_resources(adev, &resource_list,
+ acpi_pmu_dev_add_resource, &res);
+ acpi_dev_free_resource_list(&resource_list);
+ if (rc < 0 || IS_ERR(&res)) {
+ dev_err(dev, "PMU type %d: No resource address found\n", type);
+ goto err;
+ }
+
+ dev_csr = devm_ioremap_resource(dev, &res);
+ if (IS_ERR(dev_csr)) {
+ dev_err(dev, "PMU type %d: Fail to map resource\n", type);
+ rc = PTR_ERR(dev_csr);
+ goto err;
+ }
+
+ /* A PMU device node without enable-bit-index is always enabled */
+ rc = acpi_dev_get_property(adev, "enable-bit-index",
+ ACPI_TYPE_INTEGER, &obj);
+ if (rc < 0)
+ enable_bit = 0;
+ else
+ enable_bit = (int) obj->integer.value;
+
+ ctx->name = xgene_pmu_dev_name(type, enable_bit);
+ inf = &ctx->inf;
+ inf->type = type;
+ inf->csr = dev_csr;
+ inf->enable_mask = 1 << enable_bit;
+
+ return ctx;
+err:
+ devm_kfree(dev, ctx);
+ return NULL;
+}
+
+static acpi_status acpi_pmu_dev_add(acpi_handle handle, u32 level,
+ void *data, void **return_value)
+{
+ struct xgene_pmu *xgene_pmu = data;
+ struct xgene_pmu_dev_ctx *ctx;
+ struct acpi_device *adev;
+
+ if (acpi_bus_get_device(handle, &adev))
+ return AE_OK;
+ if (acpi_bus_get_status(adev) || !adev->status.present)
+ return AE_OK;
+
+ if (!strcmp(acpi_device_hid(adev), "APMC0D5D"))
+ ctx = acpi_get_pmu_hw_inf(xgene_pmu, adev, PMU_TYPE_L3C);
+ else if (!strcmp(acpi_device_hid(adev), "APMC0D5E"))
+ ctx = acpi_get_pmu_hw_inf(xgene_pmu, adev, PMU_TYPE_IOB);
+ else if (!strcmp(acpi_device_hid(adev), "APMC0D5F"))
+ ctx = acpi_get_pmu_hw_inf(xgene_pmu, adev, PMU_TYPE_MCB);
+ else if (!strcmp(acpi_device_hid(adev), "APMC0D60"))
+ ctx = acpi_get_pmu_hw_inf(xgene_pmu, adev, PMU_TYPE_MC);
+ else
+ ctx = NULL;
+
+ if (!ctx)
+ return AE_OK;
+
+ if (xgene_pmu_dev_add(xgene_pmu, ctx))
+ return AE_OK;
+
+ switch (ctx->inf.type) {
+ case PMU_TYPE_L3C:
+ list_add(&ctx->next, &xgene_pmu->l3cpmus);
+ break;
+ case PMU_TYPE_IOB:
+ list_add(&ctx->next, &xgene_pmu->iobpmus);
+ break;
+ case PMU_TYPE_MCB:
+ list_add(&ctx->next, &xgene_pmu->mcbpmus);
+ break;
+ case PMU_TYPE_MC:
+ list_add(&ctx->next, &xgene_pmu->mcpmus);
+ break;
+ }
+ return AE_OK;
+}
+
+static int acpi_pmu_probe_pmu_dev(struct xgene_pmu *xgene_pmu,
+ struct platform_device *pdev)
+{
+ struct device *dev = xgene_pmu->dev;
+ acpi_handle handle;
+ acpi_status status;
+
+ handle = ACPI_HANDLE(dev);
+ if (!handle)
+ return -EINVAL;
+
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+ acpi_pmu_dev_add, NULL, xgene_pmu, NULL);
+ if (ACPI_FAILURE(status))
+ dev_err(dev, "failed to probe PMU devices\n");
+ return 0;
+}
+#else
+static int acpi_pmu_probe_pmu_dev(struct xgene_pmu *xgene_pmu,
+ struct platform_device *pdev)
+{
+ return 0;
+}
+#endif
+
+static struct
+xgene_pmu_dev_ctx *fdt_get_pmu_hw_inf(struct xgene_pmu *xgene_pmu,
+ struct device_node *np, u32 type)
+{
+ struct device *dev = xgene_pmu->dev;
+ struct xgene_pmu_dev_ctx *ctx;
+ struct hw_pmu_info *inf;
+ void __iomem *dev_csr;
+ struct resource res;
+ int enable_bit;
+ int rc;
+
+ ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return NULL;
+ rc = of_address_to_resource(np, 0, &res);
+ if (rc < 0) {
+ dev_err(dev, "PMU type %d: No resource address found\n", type);
+ goto err;
+ }
+ dev_csr = devm_ioremap_resource(dev, &res);
+ if (IS_ERR(dev_csr)) {
+ dev_err(dev, "PMU type %d: Fail to map resource\n", type);
+ rc = PTR_ERR(dev_csr);
+ goto err;
+ }
+
+ /* A PMU device node without enable-bit-index is always enabled */
+ if (of_property_read_u32(np, "enable-bit-index", &enable_bit))
+ enable_bit = 0;
+
+ ctx->name = xgene_pmu_dev_name(type, enable_bit);
+ inf = &ctx->inf;
+ inf->type = type;
+ inf->csr = dev_csr;
+ inf->enable_mask = 1 << enable_bit;
+
+ return ctx;
+err:
+ devm_kfree(dev, ctx);
+ return NULL;
+}
+
+static int fdt_pmu_probe_pmu_dev(struct xgene_pmu *xgene_pmu,
+ struct platform_device *pdev)
+{
+ struct xgene_pmu_dev_ctx *ctx;
+ struct device_node *np;
+
+ for_each_child_of_node(pdev->dev.of_node, np) {
+ if (!of_device_is_available(np))
+ continue;
+
+ if (of_device_is_compatible(np, "apm,xgene-pmu-l3c"))
+ ctx = fdt_get_pmu_hw_inf(xgene_pmu, np, PMU_TYPE_L3C);
+ else if (of_device_is_compatible(np, "apm,xgene-pmu-iob"))
+ ctx = fdt_get_pmu_hw_inf(xgene_pmu, np, PMU_TYPE_IOB);
+ else if (of_device_is_compatible(np, "apm,xgene-pmu-mcb"))
+ ctx = fdt_get_pmu_hw_inf(xgene_pmu, np, PMU_TYPE_MCB);
+ else if (of_device_is_compatible(np, "apm,xgene-pmu-mc"))
+ ctx = fdt_get_pmu_hw_inf(xgene_pmu, np, PMU_TYPE_MC);
+ else
+ ctx = NULL;
+
+ if (!ctx)
+ continue;
+
+ if (xgene_pmu_dev_add(xgene_pmu, ctx))
+ continue;
+
+ switch (ctx->inf.type) {
+ case PMU_TYPE_L3C:
+ list_add(&ctx->next, &xgene_pmu->l3cpmus);
+ break;
+ case PMU_TYPE_IOB:
+ list_add(&ctx->next, &xgene_pmu->iobpmus);
+ break;
+ case PMU_TYPE_MCB:
+ list_add(&ctx->next, &xgene_pmu->mcbpmus);
+ break;
+ case PMU_TYPE_MC:
+ list_add(&ctx->next, &xgene_pmu->mcpmus);
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static int xgene_pmu_probe_pmu_dev(struct xgene_pmu *xgene_pmu,
+ struct platform_device *pdev)
+{
+ if (has_acpi_companion(&pdev->dev))
+ return acpi_pmu_probe_pmu_dev(xgene_pmu, pdev);
+ return fdt_pmu_probe_pmu_dev(xgene_pmu, pdev);
+}
+
+static const struct xgene_pmu_data xgene_pmu_data = {
+ .id = PCP_PMU_V1,
+ .data = 0,
+};
+
+static const struct xgene_pmu_data xgene_pmu_v2_data = {
+ .id = PCP_PMU_V2,
+ .data = 0,
+};
+
+static const struct of_device_id xgene_pmu_of_match[] = {
+ { .compatible = "apm,xgene-pmu", .data = &xgene_pmu_data },
+ { .compatible = "apm,xgene-pmu-v2", .data = &xgene_pmu_v2_data },
+ {},
+};
+MODULE_DEVICE_TABLE(of, xgene_pmu_of_match);
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id xgene_pmu_acpi_match[] = {
+ {"APMC0D5B", PCP_PMU_V1},
+ {"APMC0D5C", PCP_PMU_V2},
+ {},
+};
+MODULE_DEVICE_TABLE(acpi, xgene_pmu_acpi_match);
+#endif
+
+static int xgene_pmu_probe(struct platform_device *pdev)
+{
+ const struct xgene_pmu_data *dev_data;
+ const struct of_device_id *of_id;
+ struct xgene_pmu *xgene_pmu;
+ struct resource *res;
+ int irq, rc, i;
+ int version;
+
+ xgene_pmu = devm_kzalloc(&pdev->dev, sizeof(*xgene_pmu), GFP_KERNEL);
+ if (!xgene_pmu)
+ return -ENOMEM;
+ xgene_pmu->dev = &pdev->dev;
+ platform_set_drvdata(pdev, xgene_pmu);
+
+ version = -EINVAL;
+ of_id = of_match_device(xgene_pmu_of_match, &pdev->dev);
+ if (of_id) {
+ dev_data = (const struct xgene_pmu_data *) of_id->data;
+ version = dev_data->id;
+ }
+
+#ifdef CONFIG_ACPI
+ if (ACPI_COMPANION(&pdev->dev)) {
+ const struct acpi_device_id *acpi_id;
+
+ acpi_id = acpi_match_device(xgene_pmu_acpi_match, &pdev->dev);
+ if (acpi_id)
+ version = (int) acpi_id->driver_data;
+ }
+#endif
+ if (version < 0)
+ return -ENODEV;
+
+ INIT_LIST_HEAD(&xgene_pmu->l3cpmus);
+ INIT_LIST_HEAD(&xgene_pmu->iobpmus);
+ INIT_LIST_HEAD(&xgene_pmu->mcbpmus);
+ INIT_LIST_HEAD(&xgene_pmu->mcpmus);
+
+ xgene_pmu->version = version;
+ dev_info(&pdev->dev, "X-Gene PMU version %d\n", xgene_pmu->version);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ xgene_pmu->pcppmu_csr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(xgene_pmu->pcppmu_csr)) {
+ dev_err(&pdev->dev, "ioremap failed for PCP PMU resource\n");
+ rc = PTR_ERR(xgene_pmu->pcppmu_csr);
+ goto err;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "No IRQ resource\n");
+ rc = -EINVAL;
+ goto err;
+ }
+ rc = devm_request_irq(&pdev->dev, irq, xgene_pmu_isr, IRQF_SHARED,
+ dev_name(&pdev->dev), xgene_pmu);
+ if (rc) {
+ dev_err(&pdev->dev, "Could not request IRQ %d\n", irq);
+ goto err;
+ }
+
+ /* Check for active MCBs and MCUs */
+ rc = xgene_pmu_probe_active_mcb_mcu(xgene_pmu, pdev);
+ if (rc) {
+ dev_warn(&pdev->dev, "Unknown MCB/MCU active status\n");
+ xgene_pmu->mcb_active_mask = 0x1;
+ xgene_pmu->mc_active_mask = 0x1;
+ }
+
+ /* Pick one core to use for cpumask attributes */
+ cpumask_set_cpu(smp_processor_id(), &xgene_pmu->cpu);
+
+ /* Make sure that the overflow interrupt is handled by this CPU */
+ rc = irq_set_affinity(irq, &xgene_pmu->cpu);
+ if (rc) {
+ dev_err(&pdev->dev, "Failed to set interrupt affinity!\n");
+ goto err;
+ }
+
+ /* Enable interrupt */
+ xgene_pmu_unmask_int(xgene_pmu);
+
+ /* Populate PMU event atrribute arrays */
+ for (i = 0; i < ARRAY_SIZE(l3c_pmu_events); i++)
+ l3c_pmu_events_attrs[i] =
+ (struct attribute *) &l3c_pmu_events[i].attr.attr;
+ for (i = 0; i < ARRAY_SIZE(iob_pmu_events); i++)
+ iob_pmu_events_attrs[i] =
+ (struct attribute *) &iob_pmu_events[i].attr.attr;
+ for (i = 0; i < ARRAY_SIZE(mcb_pmu_events); i++)
+ mcb_pmu_events_attrs[i] =
+ (struct attribute *) &mcb_pmu_events[i].attr.attr;
+ for (i = 0; i < ARRAY_SIZE(mc_pmu_events); i++)
+ mc_pmu_events_attrs[i] =
+ (struct attribute *) &mc_pmu_events[i].attr.attr;
+
+ /* Walk through the tree for all PMU perf devices */
+ rc = xgene_pmu_probe_pmu_dev(xgene_pmu, pdev);
+ if (rc) {
+ dev_err(&pdev->dev, "No PMU perf devices found!\n");
+ goto err;
+ }
+
+ return 0;
+
+err:
+ if (xgene_pmu->pcppmu_csr)
+ devm_iounmap(&pdev->dev, xgene_pmu->pcppmu_csr);
+ devm_kfree(&pdev->dev, xgene_pmu);
+
+ return rc;
+}
+
+static void
+xgene_pmu_dev_cleanup(struct xgene_pmu *xgene_pmu, struct list_head *pmus)
+{
+ struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
+ struct device *dev = xgene_pmu->dev;
+ struct xgene_pmu_dev *pmu_dev;
+
+ list_for_each_entry_safe(ctx, temp_ctx, pmus, next) {
+ pmu_dev = ctx->pmu_dev;
+ if (pmu_dev->inf->csr)
+ devm_iounmap(dev, pmu_dev->inf->csr);
+ devm_kfree(dev, ctx);
+ devm_kfree(dev, pmu_dev);
+ }
+}
+
+static int xgene_pmu_remove(struct platform_device *pdev)
+{
+ struct xgene_pmu *xgene_pmu = dev_get_drvdata(&pdev->dev);
+
+ xgene_pmu_dev_cleanup(xgene_pmu, &xgene_pmu->l3cpmus);
+ xgene_pmu_dev_cleanup(xgene_pmu, &xgene_pmu->iobpmus);
+ xgene_pmu_dev_cleanup(xgene_pmu, &xgene_pmu->mcbpmus);
+ xgene_pmu_dev_cleanup(xgene_pmu, &xgene_pmu->mcpmus);
+
+ if (xgene_pmu->pcppmu_csr)
+ devm_iounmap(&pdev->dev, xgene_pmu->pcppmu_csr);
+ devm_kfree(&pdev->dev, xgene_pmu);
+
+ return 0;
+}
+
+static struct platform_driver xgene_pmu_driver = {
+ .probe = xgene_pmu_probe,
+ .remove = xgene_pmu_remove,
+ .driver = {
+ .name = "xgene-pmu",
+ .of_match_table = xgene_pmu_of_match,
+ .acpi_match_table = ACPI_PTR(xgene_pmu_acpi_match),
+ },
+};
+
+module_platform_driver(xgene_pmu_driver);
+
+MODULE_DESCRIPTION("APM X-Gene SoC PMU driver");
+MODULE_AUTHOR("Hoan Tran <hotran@apm.com>");
+MODULE_AUTHOR("Tai Nguyen <ttnguyen@apm.com>");
+MODULE_LICENSE("GPL");
--
1.9.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v4 4/4] arm64: dts: apm: Add APM X-Gene SoC PMU DTS entries
2016-06-22 18:06 [PATCH v4 0/4] perf: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
` (2 preceding siblings ...)
2016-06-22 18:06 ` [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
@ 2016-06-22 18:06 ` Tai Nguyen
3 siblings, 0 replies; 15+ messages in thread
From: Tai Nguyen @ 2016-06-22 18:06 UTC (permalink / raw)
To: mark.rutland, will.deacon, catalin.marinas
Cc: linux-kernel, devicetree, linux-arm-kernel, patches, Tai Nguyen
Signed-off-by: Tai Nguyen <ttnguyen@apm.com>
---
arch/arm64/boot/dts/apm/apm-storm.dtsi | 58 ++++++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)
diff --git a/arch/arm64/boot/dts/apm/apm-storm.dtsi b/arch/arm64/boot/dts/apm/apm-storm.dtsi
index fe30f76..62806e0 100644
--- a/arch/arm64/boot/dts/apm/apm-storm.dtsi
+++ b/arch/arm64/boot/dts/apm/apm-storm.dtsi
@@ -566,6 +566,64 @@
};
};
+ pmu: pmu@78810000 {
+ compatible = "apm,xgene-pmu-v2";
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+ regmap-csw = <&csw>;
+ regmap-mcba = <&mcba>;
+ regmap-mcbb = <&mcbb>;
+ reg = <0x0 0x78810000 0x0 0x1000>;
+ interrupts = <0x0 0x22 0x4>;
+
+ pmul3c@7e610000 {
+ compatible = "apm,xgene-pmu-l3c";
+ reg = <0x0 0x7e610000 0x0 0x1000>;
+ };
+
+ pmuiob@7e940000 {
+ compatible = "apm,xgene-pmu-iob";
+ reg = <0x0 0x7e940000 0x0 0x1000>;
+ };
+
+ pmucmcb@7e710000 {
+ compatible = "apm,xgene-pmu-mcb";
+ reg = <0x0 0x7e710000 0x0 0x1000>;
+ enable-bit-index = <0>;
+ };
+
+ pmucmcb@7e730000 {
+ compatible = "apm,xgene-pmu-mcb";
+ reg = <0x0 0x7e730000 0x0 0x1000>;
+ enable-bit-index = <1>;
+ };
+
+ pmucmc@7e810000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e810000 0x0 0x1000>;
+ enable-bit-index = <0>;
+ };
+
+ pmucmc@7e850000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e850000 0x0 0x1000>;
+ enable-bit-index = <1>;
+ };
+
+ pmucmc@7e890000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e890000 0x0 0x1000>;
+ enable-bit-index = <2>;
+ };
+
+ pmucmc@7e8d0000 {
+ compatible = "apm,xgene-pmu-mc";
+ reg = <0x0 0x7e8d0000 0x0 0x1000>;
+ enable-bit-index = <3>;
+ };
+ };
+
pcie0: pcie@1f2b0000 {
status = "disabled";
device_type = "pci";
--
1.9.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-22 18:06 ` [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
@ 2016-06-23 14:32 ` Mark Rutland
2016-06-25 17:54 ` Tai Tri Nguyen
0 siblings, 1 reply; 15+ messages in thread
From: Mark Rutland @ 2016-06-23 14:32 UTC (permalink / raw)
To: Tai Nguyen
Cc: will.deacon, catalin.marinas, linux-kernel, devicetree,
linux-arm-kernel, patches
Hi,
On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
> diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
> index 04e2653..be597dd 100644
> --- a/drivers/perf/Kconfig
> +++ b/drivers/perf/Kconfig
> @@ -12,4 +12,11 @@ config ARM_PMU
> Say y if you want to use CPU performance monitors on ARM-based
> systems.
>
> +config XGENE_PMU
> + depends on PERF_EVENTS && ARCH_XGENE
> + bool "APM SoC X-Gene PMU"
Nit: make this "APM X-Gene SoC PMU"
> + default n
> + help
> + Say y if you want to use APM X-Gene SOC performance monitors.
Nit: s/SOC/SoC/ for consistency.
[...]
> +#include <linux/acpi.h>
> +#include <linux/clk.h>
> +#include <linux/cpumask.h>
> +#include <linux/efi.h>
Looking at the driver, I don't see any reason you need linux/efi.h, and
I can't imagine why this driver would care about EFI. Please drop that
include.
The other includes look fine.
> +#define PMU_MAX_COUNTERS 4
> +#define PMU_CNT_MAX_VAL 0x100000000ULL
I was a little confused by this. Please s/VAL/PERIOD/ (as the maximum
*value* will be 0xFFFFFFFF).
> +#define _GET_CNTR(ev) (ev->hw.extra_reg.reg)
> +#define _GET_EVENTID(ev) (ev->hw.config & 0xFFULL)
> +#define _GET_AGENTID(ev) (ev->hw.extra_reg.config & 0xFFFFFFFFULL)
> +#define _GET_AGENT1ID(ev) ((ev->hw.extra_reg.config >> 32) & 0xFFFFFFFFULL)
I don't think you need to use the extra_reg fields for this. It's a
little bit confusing to use them, as the extra_reg (and branch_reg)
fields are for separately allocated PMU state.
_GET_CNTR can use hw_perf_event::idx, and _GET_AGENT*_ID can use
config_base.
> +struct xgene_pmu_dev {
> + struct hw_pmu_info *inf;
> + struct xgene_pmu *parent;
> + struct pmu pmu;
> + u8 max_counters;
> + DECLARE_BITMAP(cntr_assign_mask, PMU_MAX_COUNTERS);
> + raw_spinlock_t lock;
> + u64 max_period;
> + const struct attribute_group **attr_groups;
> + struct perf_event *pmu_counter_event[4];
> +};
I believe that the 4 should be PMU_MAX_COUNTERS, to match the bitmap.
[...]
> +#define XGENE_PMU_FORMAT_ATTR(_name, _config) \
> + struct dev_ext_attribute pmu_format_attr_##_name = \
> + { __ATTR(_name, S_IRUGO, xgene_pmu_format_show, NULL), _config }
> +
> +static XGENE_PMU_FORMAT_ATTR(l3c_eventid, "config:0-7");
> +static XGENE_PMU_FORMAT_ATTR(l3c_agentid, "config1:0-9");
> +static XGENE_PMU_FORMAT_ATTR(iob_eventid, "config:0-7");
> +static XGENE_PMU_FORMAT_ATTR(iob_agentid, "config1:0-63");
> +static XGENE_PMU_FORMAT_ATTR(mcb_eventid, "config:0-5");
> +static XGENE_PMU_FORMAT_ATTR(mcb_agentid, "config1:0-9");
> +static XGENE_PMU_FORMAT_ATTR(mc_eventid, "config:0-28");
> +
> +static const struct attribute *l3c_pmu_format_attrs[] = {
> + &pmu_format_attr_l3c_eventid.attr.attr,
> + &pmu_format_attr_l3c_agentid.attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute *iob_pmu_format_attrs[] = {
> + &pmu_format_attr_iob_eventid.attr.attr,
> + &pmu_format_attr_iob_agentid.attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute *mcb_pmu_format_attrs[] = {
> + &pmu_format_attr_mcb_eventid.attr.attr,
> + &pmu_format_attr_mcb_agentid.attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute *mc_pmu_format_attrs[] = {
> + &pmu_format_attr_mc_eventid.attr.attr,
> + NULL,
> +};
As mentioned before, you can use compound literals for these and avoid
the redundancy. There is a trick to this, which I didn't explain last
time. You need to update XGENE_PMU_FORMAT_ATTR to match what we do in
the arm-cci driver for CCI_EXT_ATTR_ENTRY, using a single element array
to allow the compiler to statically allocate an anonymous struct and
generate a pointer to a sub-field at compile time. e.g.
#define XGENE_PMU_FORMAT_ATTR(_name, _config) \
&((struct dev_ext_attribute[]) { \
{ __ATTR(_name, S_IRUGO, xgene_pmu_format_show, NULL), _config } \
})[0].attr.attr
static struct attribute *l3c_pmu_format_attrs[] = {
XGENE_PMU_FORMAT_ATTR(l3c_eventid, "config:0-7"),
XGENE_PMU_FORMAT_ATTR(l3c_agentid, "config1:0-9"),
NULL,
};
> +static const struct attribute_group l3c_pmu_format_attr_group = {
> + .name = "format",
> + .attrs = (struct attribute **) l3c_pmu_format_attrs,
> +};
I see based on that suspicious cast that attribute_group::attrs isn't
const, and so we're throwing away the constness of
xgene_pmu_cpumask_attrs here. I didn't realise that when I suggested
making the structures const; sorry for the bad advice in the last round
of review.
Forcefully casting away const isn't a great idea. For the timebeing,
please drop any casts which throw away const, and remove the instances
of const that made those necessary.
> +#define XGENE_PMU_EVENT_ATTR(_name) \
> + __ATTR(_name, S_IRUGO, xgene_pmu_event_show, NULL)
> +#define XGENE_PMU_EVENT(_name, _config) { \
> + .attr = XGENE_PMU_EVENT_ATTR(_name), \
> + .config = _config, }
> +
> +static const struct xgene_pmu_event l3c_pmu_events[] = {
> + XGENE_PMU_EVENT(cycle-count, 0x00),
> + XGENE_PMU_EVENT(cycle-count-div-64, 0x01),
> + XGENE_PMU_EVENT(read-hit, 0x02),
> + XGENE_PMU_EVENT(read-miss, 0x03),
> + XGENE_PMU_EVENT(write-need-replacement, 0x06),
> + XGENE_PMU_EVENT(write-not-need-replacement, 0x07),
> + XGENE_PMU_EVENT(tq-full, 0x08),
> + XGENE_PMU_EVENT(ackq-full, 0x09),
> + XGENE_PMU_EVENT(wdb-full, 0x0a),
> + XGENE_PMU_EVENT(bank-fifo-full, 0x0b),
> + XGENE_PMU_EVENT(odb-full, 0x0c),
> + XGENE_PMU_EVENT(wbq-full, 0x0d),
> + XGENE_PMU_EVENT(bank-conflict-fifo-issue, 0x0e),
> + XGENE_PMU_EVENT(bank-fifo-issue, 0x0f),
> +};
[...]
> +/* Populated in xgene_pmu_probe */
> +static struct attribute *l3c_pmu_events_attrs[ARRAY_SIZE(l3c_pmu_events) + 1];
> +static struct attribute *iob_pmu_events_attrs[ARRAY_SIZE(iob_pmu_events) + 1];
> +static struct attribute *mcb_pmu_events_attrs[ARRAY_SIZE(mcb_pmu_events) + 1];
> +static struct attribute *mc_pmu_events_attrs[ARRAY_SIZE(mc_pmu_events) + 1];
As with the other attributes above, please use the CCI_EXT_ATTR_ENTRY
trick to initialise these at compile time, rather than initialising this
in xgene_pmu_probe. e.g.
#define XGENE_PMU_EVENT_ATTR(_name, _config) \
&((struct xgene_pmu_event[]) {{ \
.attr = __ATTR(_name, S_IRUGO, xgene_pmu_event_show, NULL), \
.config = _config, \
}})[0].attr.attr
static struct attribute *l3c_pmu_events_attrs[] = {
XGENE_PMU_EVENT_ATTR(cycle-count, 0x00),
XGENE_PMU_EVENT_ATTR(cycle-count-div-64, 0x01),
XGENE_PMU_EVENT_ATTR(read-hit, 0x02),
XGENE_PMU_EVENT_ATTR(read-miss, 0x03),
XGENE_PMU_EVENT_ATTR(write-need-replacement, 0x06),
XGENE_PMU_EVENT_ATTR(write-not-need-replacement, 0x07),
XGENE_PMU_EVENT_ATTR(tq-full, 0x08),
XGENE_PMU_EVENT_ATTR(ackq-full, 0x09),
XGENE_PMU_EVENT_ATTR(wdb-full, 0x0a),
XGENE_PMU_EVENT_ATTR(bank-fifo-full, 0x0b),
XGENE_PMU_EVENT_ATTR(odb-full, 0x0c),
XGENE_PMU_EVENT_ATTR(wbq-full, 0x0d),
XGENE_PMU_EVENT_ATTR(bank-conflict-fifo-issue, 0x0e),
XGENE_PMU_EVENT_ATTR(bank-fifo-issue, 0x0f),
NULL,
};
> + /*
> + * Each bit of the config1 field represents an agent from which the
> + * request of the event come. The event is counted only if it's caused
> + * by a request of an agent has the bit set.
> + * By default, the event is counted for all agents.
> + */
> + if (config1)
> + hwc->extra_reg.config = config1;
> + else
> + hwc->extra_reg.config = 0xFFFFFFFFFFFFFFFFULL;
Previously I asked you to invert the meaning of this, such that the
default would be to match all masters.
I understand that in HW, you need to write 0xFFFFFFFFFFFFFFFF to match
all masters, as you mentioned in your last reply. The simple way to
handle that is to bitwise invert the value when writing it to HW , i.e.
write ~(hwc->extra_reg.config). Please do so, updating the documentation
appropriately.
[...]
> +static int xgene_perf_add(struct perf_event *event, int flags)
> +{
> + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> + struct hw_perf_event *hw = &event->hw;
> +
> + event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
Please either use event->hw.field or hw->field consistently.
> +
> + /* Allocate an event counter */
> + hw->idx = get_next_avail_cntr(pmu_dev);
> + if (hw->idx < 0)
> + return -EAGAIN;
> +
> + event->hw.extra_reg.reg = (u16) hw->idx;
That cast shouldn't be necessary, given idx will be between 0 and 4, and
reg is an unsigned int.
Given this is already in hw->idx, what is the benefit of duplicating this?
You can get rid of this line if you change _GET_CNTR to return
ev->hw.idx.
> +
> + if (flags & PERF_EF_START)
> + xgene_perf_start(event, PERF_EF_RELOAD);
> +
> + /* Update counter event pointer for Interrupt handler */
> + pmu_dev->pmu_counter_event[hw->idx] = event;
Are interrupts guaranteed to be disabled here, or should these be
swapped? Otherwise, what happens if an interrupt comes in before we
updated this pointer?
> +
> + return 0;
> +}
> +
> +static void xgene_perf_del(struct perf_event *event, int flags)
> +{
> + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> +
> + xgene_perf_stop(event, PERF_EF_UPDATE);
> +
> + /* clear the assigned counter */
> + clear_avail_cntr(pmu_dev, _GET_CNTR(event));
> +
> + perf_event_update_userpage(event);
> +}
It would be a good idea to remove the dangling pmu_dev->pmu_counter_event
pointer, even if not strictly required.
> +
> +static u64 xgene_perf_event_update(struct perf_event *event)
> +{
> + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> + u64 delta, prev_raw_count, new_raw_count;
> +
> +again:
> + prev_raw_count = local64_read(&hwc->prev_count);
> + new_raw_count = pmu_dev->max_period;
I don't understand this. Why are we not reading the counter here?
This means that the irq handler won't be reading the counter, which
means we're throwing away events, and I suspect other cases are broken
too.
> +
> + if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
> + new_raw_count) != prev_raw_count)
> + goto again;
> +
> + delta = (new_raw_count - prev_raw_count) & pmu_dev->max_period;
> +
> + local64_add(delta, &event->count);
> + local64_sub(delta, &hwc->period_left);
Given we aren't sampling, does the period left matter? It looks like
drivers are inconsistent w.r.t. this, and I'm not immediately sure :(
> +
> + return new_raw_count;
> +}
> +
> +static int xgene_perf_event_set_period(struct perf_event *event)
> +{
> + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> + s64 left = local64_read(&hwc->period_left);
> + s64 period = hwc->sample_period;
> + int ret = 0;
> +
> + if (unlikely(left <= -period)) {
> + left = period;
> + local64_set(&hwc->period_left, left);
> + hwc->last_period = period;
> + ret = 1;
> + }
> +
> + if (unlikely(left <= 0)) {
> + left += period;
> + local64_set(&hwc->period_left, left);
> + hwc->last_period = period;
> + ret = 1;
> + }
> +
> + /*
> + * Limit the maximum period to prevent the counter value
> + * from overtaking the one we are about to program. In
> + * effect we are reducing max_period to account for
> + * interrupt latency (and we are being very conservative).
> + */
> + if (left > (pmu_dev->max_period >> 1))
> + left = pmu_dev->max_period >> 1;
> +
> + local64_set(&hwc->prev_count, (u64) -left);
> +
> + xgene_pmu_write_counter(pmu_dev, hwc->idx, (u64)(-left) & 0xffffffff);
> +
> + perf_event_update_userpage(event);
> +
> + return ret;
> +}
Given the lack of sampling, I suspect that you can simply follow what
the arm-cci driver does, and always use exactly half a max period.
[...]
> +static irqreturn_t _xgene_pmu_isr(int irq, struct xgene_pmu_dev *pmu_dev)
> +{
> + struct xgene_pmu *xgene_pmu = pmu_dev->parent;
> + u32 pmovsr;
> + int idx;
> +
> + pmovsr = readl(pmu_dev->inf->csr + PMU_PMOVSR) & PMU_OVERFLOW_MASK;
> + /* Clear interrupt flag */
> + if (xgene_pmu->version == PCP_PMU_V1)
> + writel(0x0, pmu_dev->inf->csr + PMU_PMOVSR);
> + else
> + writel(pmovsr, pmu_dev->inf->csr + PMU_PMOVSR);
> +
> + if (!pmovsr)
> + return IRQ_NONE;
> +
> + for (idx = 0; idx < PMU_MAX_COUNTERS; idx++) {
> + struct perf_event *event = pmu_dev->pmu_counter_event[idx];
> + int overflowed = pmovsr & BIT(idx);
> +
> + /* Ignore if we don't have an event. */
> + if (!event || !overflowed)
> + continue;
> + xgene_perf_event_update(event);
> + xgene_perf_event_set_period(event);
As I mentioned earlier, the lack of a counter read in
xgene_perf_event_update() means this is broken.
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
> +{
> + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
> + struct xgene_pmu *xgene_pmu = dev_id;
> + u32 val;
> +
> + xgene_pmu_mask_int(xgene_pmu);
Why do you need to mask the IRQ? This handler is called in hard IRQ
context.
> +
> + /* Get Interrupt PMU source */
> + val = readl(xgene_pmu->pcppmu_csr + PCPPMU_INTSTATUS_REG)
> + & PCPPMU_INTMASK;
I don't think you need the mask here, given you only test masks below.
I think that can be removed.
Otherwise, please leave the '&' dangling on the first line.
> + if (val & PCPPMU_INT_MCU) {
> + list_for_each_entry_safe(ctx, temp_ctx,
> + &xgene_pmu->mcpmus, next) {
> + _xgene_pmu_isr(irq, ctx->pmu_dev);
> + }
> + }
> + if (val & PCPPMU_INT_MCB) {
> + list_for_each_entry_safe(ctx, temp_ctx,
> + &xgene_pmu->mcbpmus, next) {
> + _xgene_pmu_isr(irq, ctx->pmu_dev);
> + }
> + }
> + if (val & PCPPMU_INT_L3C) {
> + list_for_each_entry_safe(ctx, temp_ctx,
> + &xgene_pmu->l3cpmus, next) {
> + _xgene_pmu_isr(irq, ctx->pmu_dev);
> + }
> + }
> + if (val & PCPPMU_INT_IOB) {
> + list_for_each_entry_safe(ctx, temp_ctx,
> + &xgene_pmu->iobpmus, next) {
> + _xgene_pmu_isr(irq, ctx->pmu_dev);
> + }
> + }
> +
> + xgene_pmu_unmask_int(xgene_pmu);
> +
> + return IRQ_HANDLED;
> +}
[...]
> + /* Populate PMU event atrribute arrays */
> + for (i = 0; i < ARRAY_SIZE(l3c_pmu_events); i++)
> + l3c_pmu_events_attrs[i] =
> + (struct attribute *) &l3c_pmu_events[i].attr.attr;
> + for (i = 0; i < ARRAY_SIZE(iob_pmu_events); i++)
> + iob_pmu_events_attrs[i] =
> + (struct attribute *) &iob_pmu_events[i].attr.attr;
> + for (i = 0; i < ARRAY_SIZE(mcb_pmu_events); i++)
> + mcb_pmu_events_attrs[i] =
> + (struct attribute *) &mcb_pmu_events[i].attr.attr;
> + for (i = 0; i < ARRAY_SIZE(mc_pmu_events); i++)
> + mc_pmu_events_attrs[i] =
> + (struct attribute *) &mc_pmu_events[i].attr.attr;
As mentioend earlier, you can do this at compile time. Please do.
Thanks,
Mark.
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-23 14:32 ` Mark Rutland
@ 2016-06-25 17:54 ` Tai Tri Nguyen
2016-06-27 16:00 ` Mark Rutland
0 siblings, 1 reply; 15+ messages in thread
From: Tai Tri Nguyen @ 2016-06-25 17:54 UTC (permalink / raw)
To: Mark Rutland
Cc: Will Deacon, catalin.marinas, linux-kernel, devicetree,
linux-arm-kernel, patches
Hi Mark,
On Thu, Jun 23, 2016 at 7:32 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>
> Hi,
>
> On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
> > diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
> > index 04e2653..be597dd 100644
> > --- a/drivers/perf/Kconfig
> > +++ b/drivers/perf/Kconfig
> > @@ -12,4 +12,11 @@ config ARM_PMU
> > Say y if you want to use CPU performance monitors on ARM-based
> > systems.
> >
> > +config XGENE_PMU
> > + depends on PERF_EVENTS && ARCH_XGENE
> > + bool "APM SoC X-Gene PMU"
>
> Nit: make this "APM X-Gene SoC PMU"
Okay
>
>
> > + default n
> > + help
> > + Say y if you want to use APM X-Gene SOC performance monitors.
>
> Nit: s/SOC/SoC/ for consistency.
>
Okay
> [...]
>
> > +#include <linux/acpi.h>
> > +#include <linux/clk.h>
> > +#include <linux/cpumask.h>
> > +#include <linux/efi.h>
>
> Looking at the driver, I don't see any reason you need linux/efi.h, and
> I can't imagine why this driver would care about EFI. Please drop that
> include.
>
> The other includes look fine.
You're right. I'll drop it.
>
> > +#define PMU_MAX_COUNTERS 4
> > +#define PMU_CNT_MAX_VAL 0x100000000ULL
>
> I was a little confused by this. Please s/VAL/PERIOD/ (as the maximum
> *value* will be 0xFFFFFFFF).
Okay, I'll change it
>
> > +#define _GET_CNTR(ev) (ev->hw.extra_reg.reg)
> > +#define _GET_EVENTID(ev) (ev->hw.config & 0xFFULL)
> > +#define _GET_AGENTID(ev) (ev->hw.extra_reg.config & 0xFFFFFFFFULL)
> > +#define _GET_AGENT1ID(ev) ((ev->hw.extra_reg.config >> 32) & 0xFFFFFFFFULL)
>
> I don't think you need to use the extra_reg fields for this. It's a
> little bit confusing to use them, as the extra_reg (and branch_reg)
> fields are for separately allocated PMU state.
>
> _GET_CNTR can use hw_perf_event::idx, and _GET_AGENT*_ID can use
> config_base.
I need a 64 bit field for GET_AGENT*ID. The config_base is only 32 bit.
Can you please suggest another field?
For _GET_CNTR, yes I'll use hw::idx.
>
> > +struct xgene_pmu_dev {
> > + struct hw_pmu_info *inf;
> > + struct xgene_pmu *parent;
> > + struct pmu pmu;
> > + u8 max_counters;
> > + DECLARE_BITMAP(cntr_assign_mask, PMU_MAX_COUNTERS);
> > + raw_spinlock_t lock;
> > + u64 max_period;
> > + const struct attribute_group **attr_groups;
> > + struct perf_event *pmu_counter_event[4];
> > +};
>
> I believe that the 4 should be PMU_MAX_COUNTERS, to match the bitmap.
>
Will fix it.
> [...]
>
> > +#define XGENE_PMU_FORMAT_ATTR(_name, _config) \
> > + struct dev_ext_attribute pmu_format_attr_##_name = \
> > + { __ATTR(_name, S_IRUGO, xgene_pmu_format_show, NULL), _config }
> > +
> > +static XGENE_PMU_FORMAT_ATTR(l3c_eventid, "config:0-7");
> > +static XGENE_PMU_FORMAT_ATTR(l3c_agentid, "config1:0-9");
> > +static XGENE_PMU_FORMAT_ATTR(iob_eventid, "config:0-7");
> > +static XGENE_PMU_FORMAT_ATTR(iob_agentid, "config1:0-63");
> > +static XGENE_PMU_FORMAT_ATTR(mcb_eventid, "config:0-5");
> > +static XGENE_PMU_FORMAT_ATTR(mcb_agentid, "config1:0-9");
> > +static XGENE_PMU_FORMAT_ATTR(mc_eventid, "config:0-28");
> > +
> > +static const struct attribute *l3c_pmu_format_attrs[] = {
> > + &pmu_format_attr_l3c_eventid.attr.attr,
> > + &pmu_format_attr_l3c_agentid.attr.attr,
> > + NULL,
> > +};
> > +
> > +static const struct attribute *iob_pmu_format_attrs[] = {
> > + &pmu_format_attr_iob_eventid.attr.attr,
> > + &pmu_format_attr_iob_agentid.attr.attr,
> > + NULL,
> > +};
> > +
> > +static const struct attribute *mcb_pmu_format_attrs[] = {
> > + &pmu_format_attr_mcb_eventid.attr.attr,
> > + &pmu_format_attr_mcb_agentid.attr.attr,
> > + NULL,
> > +};
> > +
> > +static const struct attribute *mc_pmu_format_attrs[] = {
> > + &pmu_format_attr_mc_eventid.attr.attr,
> > + NULL,
> > +};
>
> As mentioned before, you can use compound literals for these and avoid
> the redundancy. There is a trick to this, which I didn't explain last
> time. You need to update XGENE_PMU_FORMAT_ATTR to match what we do in
> the arm-cci driver for CCI_EXT_ATTR_ENTRY, using a single element array
> to allow the compiler to statically allocate an anonymous struct and
> generate a pointer to a sub-field at compile time. e.g.
>
> #define XGENE_PMU_FORMAT_ATTR(_name, _config) \
> &((struct dev_ext_attribute[]) { \
> { __ATTR(_name, S_IRUGO, xgene_pmu_format_show, NULL), _config } \
> })[0].attr.attr
>
> static struct attribute *l3c_pmu_format_attrs[] = {
> XGENE_PMU_FORMAT_ATTR(l3c_eventid, "config:0-7"),
> XGENE_PMU_FORMAT_ATTR(l3c_agentid, "config1:0-9"),
> NULL,
> };
Thanks, I'll make change as per your suggestion.
>
> > +static const struct attribute_group l3c_pmu_format_attr_group = {
> > + .name = "format",
> > + .attrs = (struct attribute **) l3c_pmu_format_attrs,
> > +};
>
> I see based on that suspicious cast that attribute_group::attrs isn't
> const, and so we're throwing away the constness of
> xgene_pmu_cpumask_attrs here. I didn't realise that when I suggested
> making the structures const; sorry for the bad advice in the last round
> of review.
>
> Forcefully casting away const isn't a great idea. For the timebeing,
> please drop any casts which throw away const, and remove the instances
> of const that made those necessary.
>
Yes, I agree.
> > +#define XGENE_PMU_EVENT_ATTR(_name) \
> > + __ATTR(_name, S_IRUGO, xgene_pmu_event_show, NULL)
> > +#define XGENE_PMU_EVENT(_name, _config) { \
> > + .attr = XGENE_PMU_EVENT_ATTR(_name), \
> > + .config = _config, }
> > +
> > +static const struct xgene_pmu_event l3c_pmu_events[] = {
> > + XGENE_PMU_EVENT(cycle-count, 0x00),
> > + XGENE_PMU_EVENT(cycle-count-div-64, 0x01),
> > + XGENE_PMU_EVENT(read-hit, 0x02),
> > + XGENE_PMU_EVENT(read-miss, 0x03),
> > + XGENE_PMU_EVENT(write-need-replacement, 0x06),
> > + XGENE_PMU_EVENT(write-not-need-replacement, 0x07),
> > + XGENE_PMU_EVENT(tq-full, 0x08),
> > + XGENE_PMU_EVENT(ackq-full, 0x09),
> > + XGENE_PMU_EVENT(wdb-full, 0x0a),
> > + XGENE_PMU_EVENT(bank-fifo-full, 0x0b),
> > + XGENE_PMU_EVENT(odb-full, 0x0c),
> > + XGENE_PMU_EVENT(wbq-full, 0x0d),
> > + XGENE_PMU_EVENT(bank-conflict-fifo-issue, 0x0e),
> > + XGENE_PMU_EVENT(bank-fifo-issue, 0x0f),
> > +};
>
> [...]
>
> > +/* Populated in xgene_pmu_probe */
> > +static struct attribute *l3c_pmu_events_attrs[ARRAY_SIZE(l3c_pmu_events) + 1];
> > +static struct attribute *iob_pmu_events_attrs[ARRAY_SIZE(iob_pmu_events) + 1];
> > +static struct attribute *mcb_pmu_events_attrs[ARRAY_SIZE(mcb_pmu_events) + 1];
> > +static struct attribute *mc_pmu_events_attrs[ARRAY_SIZE(mc_pmu_events) + 1];
>
> As with the other attributes above, please use the CCI_EXT_ATTR_ENTRY
> trick to initialise these at compile time, rather than initialising this
> in xgene_pmu_probe. e.g.
>
> #define XGENE_PMU_EVENT_ATTR(_name, _config) \
> &((struct xgene_pmu_event[]) {{ \
> .attr = __ATTR(_name, S_IRUGO, xgene_pmu_event_show, NULL), \
> .config = _config, \
> }})[0].attr.attr
>
> static struct attribute *l3c_pmu_events_attrs[] = {
> XGENE_PMU_EVENT_ATTR(cycle-count, 0x00),
> XGENE_PMU_EVENT_ATTR(cycle-count-div-64, 0x01),
> XGENE_PMU_EVENT_ATTR(read-hit, 0x02),
> XGENE_PMU_EVENT_ATTR(read-miss, 0x03),
> XGENE_PMU_EVENT_ATTR(write-need-replacement, 0x06),
> XGENE_PMU_EVENT_ATTR(write-not-need-replacement, 0x07),
> XGENE_PMU_EVENT_ATTR(tq-full, 0x08),
> XGENE_PMU_EVENT_ATTR(ackq-full, 0x09),
> XGENE_PMU_EVENT_ATTR(wdb-full, 0x0a),
> XGENE_PMU_EVENT_ATTR(bank-fifo-full, 0x0b),
> XGENE_PMU_EVENT_ATTR(odb-full, 0x0c),
> XGENE_PMU_EVENT_ATTR(wbq-full, 0x0d),
> XGENE_PMU_EVENT_ATTR(bank-conflict-fifo-issue, 0x0e),
> XGENE_PMU_EVENT_ATTR(bank-fifo-issue, 0x0f),
> NULL,
> };
Got it. I'll do the same as format attribute groups
>
> > + /*
> > + * Each bit of the config1 field represents an agent from which the
> > + * request of the event come. The event is counted only if it's caused
> > + * by a request of an agent has the bit set.
> > + * By default, the event is counted for all agents.
> > + */
> > + if (config1)
> > + hwc->extra_reg.config = config1;
> > + else
> > + hwc->extra_reg.config = 0xFFFFFFFFFFFFFFFFULL;
>
> Previously I asked you to invert the meaning of this, such that the
> default would be to match all masters.
>
> I understand that in HW, you need to write 0xFFFFFFFFFFFFFFFF to match
> all masters, as you mentioned in your last reply. The simple way to
> handle that is to bitwise invert the value when writing it to HW , i.e.
> write ~(hwc->extra_reg.config). Please do so, updating the documentation
> appropriately.
>
Okay. I'll do so.
> [...]
>
> > +static int xgene_perf_add(struct perf_event *event, int flags)
> > +{
> > + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> > + struct hw_perf_event *hw = &event->hw;
> > +
> > + event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
>
> Please either use event->hw.field or hw->field consistently.
Okay, will fix it consistently.
>
> > +
> > + /* Allocate an event counter */
> > + hw->idx = get_next_avail_cntr(pmu_dev);
> > + if (hw->idx < 0)
> > + return -EAGAIN;
> > +
> > + event->hw.extra_reg.reg = (u16) hw->idx;
>
> That cast shouldn't be necessary, given idx will be between 0 and 4, and
> reg is an unsigned int.
>
> Given this is already in hw->idx, what is the benefit of duplicating this?
>
> You can get rid of this line if you change _GET_CNTR to return
> ev->hw.idx.
Yes, I'll fix it.
>
> > +
> > + if (flags & PERF_EF_START)
> > + xgene_perf_start(event, PERF_EF_RELOAD);
> > +
> > + /* Update counter event pointer for Interrupt handler */
> > + pmu_dev->pmu_counter_event[hw->idx] = event;
>
> Are interrupts guaranteed to be disabled here, or should these be
> swapped? Otherwise, what happens if an interrupt comes in before we
> updated this pointer?
Right. Naturally, this should be updated before starting perf event.
I'll swap these. Thanks for catching it.
>
> > +
> > + return 0;
> > +}
> > +
> > +static void xgene_perf_del(struct perf_event *event, int flags)
> > +{
> > + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> > +
> > + xgene_perf_stop(event, PERF_EF_UPDATE);
> > +
> > + /* clear the assigned counter */
> > + clear_avail_cntr(pmu_dev, _GET_CNTR(event));
> > +
> > + perf_event_update_userpage(event);
> > +}
>
> It would be a good idea to remove the dangling pmu_dev->pmu_counter_event
> pointer, even if not strictly required.
Sure, I'll reset it to NULL.
>
> > +
> > +static u64 xgene_perf_event_update(struct perf_event *event)
> > +{
> > + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > + u64 delta, prev_raw_count, new_raw_count;
> > +
> > +again:
> > + prev_raw_count = local64_read(&hwc->prev_count);
> > + new_raw_count = pmu_dev->max_period;
>
> I don't understand this. Why are we not reading the counter here?
>
> This means that the irq handler won't be reading the counter, which
> means we're throwing away events, and I suspect other cases are broken
> too.
>
When the overflow interrupt occurs, the PMU counter wraps to 0 and
continues to run.
This event_update function is called only to handle the The PMU
counter overflow interrupt occurs.
I'm assuming that when the overflow happens, the read back counter
value is the max period.
Is this assumption incorrect? Do you have any suggestion what I should
do. Because if I read the counter register,
it returns the minor wrapped around value.
Or should it be: new_count = counter read + max period?
> > +
> > + if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
> > + new_raw_count) != prev_raw_count)
> > + goto again;
> > +
> > + delta = (new_raw_count - prev_raw_count) & pmu_dev->max_period;
> > +
> > + local64_add(delta, &event->count);
> > + local64_sub(delta, &hwc->period_left);
>
> Given we aren't sampling, does the period left matter? It looks like
> drivers are inconsistent w.r.t. this, and I'm not immediately sure :(
>
I tried to drop it and the perf event count still works properly for me.
I'll remove it.
> > +
> > + return new_raw_count;
> > +}
> > +
> > +static int xgene_perf_event_set_period(struct perf_event *event)
> > +{
> > + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > + s64 left = local64_read(&hwc->period_left);
> > + s64 period = hwc->sample_period;
> > + int ret = 0;
> > +
> > + if (unlikely(left <= -period)) {
> > + left = period;
> > + local64_set(&hwc->period_left, left);
> > + hwc->last_period = period;
> > + ret = 1;
> > + }
> > +
> > + if (unlikely(left <= 0)) {
> > + left += period;
> > + local64_set(&hwc->period_left, left);
> > + hwc->last_period = period;
> > + ret = 1;
> > + }
> > +
> > + /*
> > + * Limit the maximum period to prevent the counter value
> > + * from overtaking the one we are about to program. In
> > + * effect we are reducing max_period to account for
> > + * interrupt latency (and we are being very conservative).
> > + */
> > + if (left > (pmu_dev->max_period >> 1))
> > + left = pmu_dev->max_period >> 1;
> > +
> > + local64_set(&hwc->prev_count, (u64) -left);
> > +
> > + xgene_pmu_write_counter(pmu_dev, hwc->idx, (u64)(-left) & 0xffffffff);
> > +
> > + perf_event_update_userpage(event);
> > +
> > + return ret;
> > +}
>
> Given the lack of sampling, I suspect that you can simply follow what
> the arm-cci driver does, and always use exactly half a max period.
Okay, I'll refer to the arm-cci driver.
>
> [...]
>
> > +static irqreturn_t _xgene_pmu_isr(int irq, struct xgene_pmu_dev *pmu_dev)
> > +{
> > + struct xgene_pmu *xgene_pmu = pmu_dev->parent;
> > + u32 pmovsr;
> > + int idx;
> > +
> > + pmovsr = readl(pmu_dev->inf->csr + PMU_PMOVSR) & PMU_OVERFLOW_MASK;
> > + /* Clear interrupt flag */
> > + if (xgene_pmu->version == PCP_PMU_V1)
> > + writel(0x0, pmu_dev->inf->csr + PMU_PMOVSR);
> > + else
> > + writel(pmovsr, pmu_dev->inf->csr + PMU_PMOVSR);
> > +
> > + if (!pmovsr)
> > + return IRQ_NONE;
> > +
> > + for (idx = 0; idx < PMU_MAX_COUNTERS; idx++) {
> > + struct perf_event *event = pmu_dev->pmu_counter_event[idx];
> > + int overflowed = pmovsr & BIT(idx);
> > +
> > + /* Ignore if we don't have an event. */
> > + if (!event || !overflowed)
> > + continue;
> > + xgene_perf_event_update(event);
> > + xgene_perf_event_set_period(event);
>
> As I mentioned earlier, the lack of a counter read in
> xgene_perf_event_update() means this is broken.
>
Please see above.
> > + }
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
> > +{
> > + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
> > + struct xgene_pmu *xgene_pmu = dev_id;
> > + u32 val;
> > +
> > + xgene_pmu_mask_int(xgene_pmu);
>
> Why do you need to mask the IRQ? This handler is called in hard IRQ
> context.
>
Right. Let me change to use raw_spin_lock_irqsave here.
> > +
> > + /* Get Interrupt PMU source */
> > + val = readl(xgene_pmu->pcppmu_csr + PCPPMU_INTSTATUS_REG)
> > + & PCPPMU_INTMASK;
>
> I don't think you need the mask here, given you only test masks below.
> I think that can be removed.
>
> Otherwise, please leave the '&' dangling on the first line.
Right, this is not necessary. I'll remove it.
>
> > + if (val & PCPPMU_INT_MCU) {
> > + list_for_each_entry_safe(ctx, temp_ctx,
> > + &xgene_pmu->mcpmus, next) {
> > + _xgene_pmu_isr(irq, ctx->pmu_dev);
> > + }
> > + }
> > + if (val & PCPPMU_INT_MCB) {
> > + list_for_each_entry_safe(ctx, temp_ctx,
> > + &xgene_pmu->mcbpmus, next) {
> > + _xgene_pmu_isr(irq, ctx->pmu_dev);
> > + }
> > + }
> > + if (val & PCPPMU_INT_L3C) {
> > + list_for_each_entry_safe(ctx, temp_ctx,
> > + &xgene_pmu->l3cpmus, next) {
> > + _xgene_pmu_isr(irq, ctx->pmu_dev);
> > + }
> > + }
> > + if (val & PCPPMU_INT_IOB) {
> > + list_for_each_entry_safe(ctx, temp_ctx,
> > + &xgene_pmu->iobpmus, next) {
> > + _xgene_pmu_isr(irq, ctx->pmu_dev);
> > + }
> > + }
> > +
> > + xgene_pmu_unmask_int(xgene_pmu);
> > +
> > + return IRQ_HANDLED;
> > +}
>
> [...]
>
> > + /* Populate PMU event atrribute arrays */
> > + for (i = 0; i < ARRAY_SIZE(l3c_pmu_events); i++)
> > + l3c_pmu_events_attrs[i] =
> > + (struct attribute *) &l3c_pmu_events[i].attr.attr;
> > + for (i = 0; i < ARRAY_SIZE(iob_pmu_events); i++)
> > + iob_pmu_events_attrs[i] =
> > + (struct attribute *) &iob_pmu_events[i].attr.attr;
> > + for (i = 0; i < ARRAY_SIZE(mcb_pmu_events); i++)
> > + mcb_pmu_events_attrs[i] =
> > + (struct attribute *) &mcb_pmu_events[i].attr.attr;
> > + for (i = 0; i < ARRAY_SIZE(mc_pmu_events); i++)
> > + mc_pmu_events_attrs[i] =
> > + (struct attribute *) &mc_pmu_events[i].attr.attr;
>
> As mentioend earlier, you can do this at compile time. Please do.
Yes, I'll do so.
Thanks,
--
Tai
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-25 17:54 ` Tai Tri Nguyen
@ 2016-06-27 16:00 ` Mark Rutland
2016-06-27 17:54 ` Tai Tri Nguyen
0 siblings, 1 reply; 15+ messages in thread
From: Mark Rutland @ 2016-06-27 16:00 UTC (permalink / raw)
To: Tai Tri Nguyen
Cc: Will Deacon, catalin.marinas, linux-kernel, devicetree,
linux-arm-kernel, patches
Hi,
On Sat, Jun 25, 2016 at 10:54:20AM -0700, Tai Tri Nguyen wrote:
> On Thu, Jun 23, 2016 at 7:32 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> > On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
> > > +#define _GET_CNTR(ev) (ev->hw.extra_reg.reg)
> > > +#define _GET_EVENTID(ev) (ev->hw.config & 0xFFULL)
> > > +#define _GET_AGENTID(ev) (ev->hw.extra_reg.config & 0xFFFFFFFFULL)
> > > +#define _GET_AGENT1ID(ev) ((ev->hw.extra_reg.config >> 32) & 0xFFFFFFFFULL)
> >
> > I don't think you need to use the extra_reg fields for this. It's a
> > little bit confusing to use them, as the extra_reg (and branch_reg)
> > fields are for separately allocated PMU state.
> >
> > _GET_CNTR can use hw_perf_event::idx, and _GET_AGENT*_ID can use
> > config_base.
>
> I need a 64 bit field for GET_AGENT*ID. The config_base is only 32 bit.
> Can you please suggest another field?
Judging by <linux/perf_event.h> config_base is an unsigned long, which
will be 64 bit for arm64, which is the only place this is used.
So unless I've missed something, that should be ok, no?
> > > +static u64 xgene_perf_event_update(struct perf_event *event)
> > > +{
> > > + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
> > > + struct hw_perf_event *hwc = &event->hw;
> > > + u64 delta, prev_raw_count, new_raw_count;
> > > +
> > > +again:
> > > + prev_raw_count = local64_read(&hwc->prev_count);
> > > + new_raw_count = pmu_dev->max_period;
> >
> > I don't understand this. Why are we not reading the counter here?
> >
> > This means that the irq handler won't be reading the counter, which
> > means we're throwing away events, and I suspect other cases are broken
> > too.
> >
>
> When the overflow interrupt occurs, the PMU counter wraps to 0 and
> continues to run.
> This event_update function is called only to handle the The PMU
> counter overflow interrupt occurs.
> I'm assuming that when the overflow happens, the read back counter
> value is the max period.
Well, it could be a larger value depending on the latency.
> Is this assumption incorrect? Do you have any suggestion what I should
> do. Because if I read the counter register,
> it returns the minor wrapped around value.
> Or should it be: new_count = counter read + max period?
We handle the wraparound when we caluclate the delta below. By setting
the interrupt to occur within half of the max period (as per the arm-cci
driver), we avoid (with a high degree of certainty) the risk of
overtaking the prev raw count again before handlnig the IRQ.
The raw_* values above should be the *raw* values from the HW, as their
names imply.
> > > + if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
> > > + new_raw_count) != prev_raw_count)
> > > + goto again;
> > > +
> > > + delta = (new_raw_count - prev_raw_count) & pmu_dev->max_period;
> > > +
> > > + local64_add(delta, &event->count);
> > > + local64_sub(delta, &hwc->period_left);
> >
> > Given we aren't sampling, does the period left matter? It looks like
> > drivers are inconsistent w.r.t. this, and I'm not immediately sure :(
>
> I tried to drop it and the perf event count still works properly for me.
> I'll remove it.
[...]
> > > +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
> > > +{
> > > + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
> > > + struct xgene_pmu *xgene_pmu = dev_id;
> > > + u32 val;
> > > +
> > > + xgene_pmu_mask_int(xgene_pmu);
> >
> > Why do you need to mask the IRQ? This handler is called in hard IRQ
> > context.
>
> Right. Let me change to use raw_spin_lock_irqsave here.
Interesting; I see we do that in the CCI PMU driver. What are we trying
to protect?
We don't do that in the CPU PMU drivers, and I'm missng something here.
Hopefully I'm just being thick...
Thanks,
Mark.
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-27 16:00 ` Mark Rutland
@ 2016-06-27 17:54 ` Tai Tri Nguyen
2016-06-28 11:13 ` Mark Rutland
0 siblings, 1 reply; 15+ messages in thread
From: Tai Tri Nguyen @ 2016-06-27 17:54 UTC (permalink / raw)
To: Mark Rutland
Cc: Will Deacon, catalin.marinas, linux-kernel, devicetree,
linux-arm-kernel, patches
Hi Mark,
On Mon, Jun 27, 2016 at 9:00 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> Hi,
>
> On Sat, Jun 25, 2016 at 10:54:20AM -0700, Tai Tri Nguyen wrote:
>> On Thu, Jun 23, 2016 at 7:32 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>> > On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
>> > > +#define _GET_CNTR(ev) (ev->hw.extra_reg.reg)
>> > > +#define _GET_EVENTID(ev) (ev->hw.config & 0xFFULL)
>> > > +#define _GET_AGENTID(ev) (ev->hw.extra_reg.config & 0xFFFFFFFFULL)
>> > > +#define _GET_AGENT1ID(ev) ((ev->hw.extra_reg.config >> 32) & 0xFFFFFFFFULL)
>> >
>> > I don't think you need to use the extra_reg fields for this. It's a
>> > little bit confusing to use them, as the extra_reg (and branch_reg)
>> > fields are for separately allocated PMU state.
>> >
>> > _GET_CNTR can use hw_perf_event::idx, and _GET_AGENT*_ID can use
>> > config_base.
>>
>> I need a 64 bit field for GET_AGENT*ID. The config_base is only 32 bit.
>> Can you please suggest another field?
>
> Judging by <linux/perf_event.h> config_base is an unsigned long, which
> will be 64 bit for arm64, which is the only place this is used.
>
> So unless I've missed something, that should be ok, no?
>
I missed the point. Okay, I'll make the change.
>> > > +static u64 xgene_perf_event_update(struct perf_event *event)
>> > > +{
>> > > + struct xgene_pmu_dev *pmu_dev = to_pmu_dev(event->pmu);
>> > > + struct hw_perf_event *hwc = &event->hw;
>> > > + u64 delta, prev_raw_count, new_raw_count;
>> > > +
>> > > +again:
>> > > + prev_raw_count = local64_read(&hwc->prev_count);
>> > > + new_raw_count = pmu_dev->max_period;
>> >
>> > I don't understand this. Why are we not reading the counter here?
>> >
>> > This means that the irq handler won't be reading the counter, which
>> > means we're throwing away events, and I suspect other cases are broken
>> > too.
>> >
>>
>> When the overflow interrupt occurs, the PMU counter wraps to 0 and
>> continues to run.
>> This event_update function is called only to handle the The PMU
>> counter overflow interrupt occurs.
>> I'm assuming that when the overflow happens, the read back counter
>> value is the max period.
>
> Well, it could be a larger value depending on the latency.
>
>> Is this assumption incorrect? Do you have any suggestion what I should
>> do. Because if I read the counter register,
>> it returns the minor wrapped around value.
>> Or should it be: new_count = counter read + max period?
>
> We handle the wraparound when we caluclate the delta below. By setting
> the interrupt to occur within half of the max period (as per the arm-cci
> driver), we avoid (with a high degree of certainty) the risk of
> overtaking the prev raw count again before handlnig the IRQ.
>
> The raw_* values above should be the *raw* values from the HW, as their
> names imply.
Yes, I got it now. The same implementation should work fine for me.
>
>> > > + if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
>> > > + new_raw_count) != prev_raw_count)
>> > > + goto again;
>> > > +
>> > > + delta = (new_raw_count - prev_raw_count) & pmu_dev->max_period;
>> > > +
>> > > + local64_add(delta, &event->count);
>> > > + local64_sub(delta, &hwc->period_left);
>> >
>> > Given we aren't sampling, does the period left matter? It looks like
>> > drivers are inconsistent w.r.t. this, and I'm not immediately sure :(
>>
>> I tried to drop it and the perf event count still works properly for me.
>> I'll remove it.
>
> [...]
>
>> > > +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
>> > > +{
>> > > + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
>> > > + struct xgene_pmu *xgene_pmu = dev_id;
>> > > + u32 val;
>> > > +
>> > > + xgene_pmu_mask_int(xgene_pmu);
>> >
>> > Why do you need to mask the IRQ? This handler is called in hard IRQ
>> > context.
>>
>> Right. Let me change to use raw_spin_lock_irqsave here.
>
> Interesting; I see we do that in the CCI PMU driver. What are we trying
> to protect?
>
> We don't do that in the CPU PMU drivers, and I'm missng something here.
> Hopefully I'm just being thick...
For me, we can't guarantee that the interrupt doesn't happen on the other CPUs.
The irqbalancer may change the SMP affinity.
Thanks,
--
Tai
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-27 17:54 ` Tai Tri Nguyen
@ 2016-06-28 11:13 ` Mark Rutland
2016-06-28 13:21 ` Marc Zyngier
0 siblings, 1 reply; 15+ messages in thread
From: Mark Rutland @ 2016-06-28 11:13 UTC (permalink / raw)
To: Tai Tri Nguyen, marc.zyngier
Cc: Will Deacon, catalin.marinas, linux-kernel, devicetree,
linux-arm-kernel, patches
On Mon, Jun 27, 2016 at 10:54:07AM -0700, Tai Tri Nguyen wrote:
> On Mon, Jun 27, 2016 at 9:00 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> > On Sat, Jun 25, 2016 at 10:54:20AM -0700, Tai Tri Nguyen wrote:
> >> On Thu, Jun 23, 2016 at 7:32 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> >> > On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
> >> > > +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
> >> > > +{
> >> > > + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
> >> > > + struct xgene_pmu *xgene_pmu = dev_id;
> >> > > + u32 val;
> >> > > +
> >> > > + xgene_pmu_mask_int(xgene_pmu);
> >> >
> >> > Why do you need to mask the IRQ? This handler is called in hard IRQ
> >> > context.
> >>
> >> Right. Let me change to use raw_spin_lock_irqsave here.
> >
> > Interesting; I see we do that in the CCI PMU driver. What are we trying
> > to protect?
> >
> > We don't do that in the CPU PMU drivers, and I'm missng something here.
> > Hopefully I'm just being thick...
>
> For me, we can't guarantee that the interrupt doesn't happen on the other CPUs.
> The irqbalancer may change the SMP affinity.
The perf core requires things to occur on the same CPU for correct
synchronisation.
If an IRQ balancer can change the IRQ affinity behind our back, we have
much bigger problems that affect other uncore PMU drivers.
Marc, is there a sensible way to prevent irq balancers from changing the
affinity of an IRQ, e.g. a kernel-side pinning mechanism, or some way we
can be notified and reject changes?
Thanks,
Mark.
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-28 11:13 ` Mark Rutland
@ 2016-06-28 13:21 ` Marc Zyngier
2016-06-28 14:14 ` Mark Rutland
0 siblings, 1 reply; 15+ messages in thread
From: Marc Zyngier @ 2016-06-28 13:21 UTC (permalink / raw)
To: Mark Rutland, Tai Tri Nguyen
Cc: Will Deacon, catalin.marinas, linux-kernel, devicetree,
linux-arm-kernel, patches
On 28/06/16 12:13, Mark Rutland wrote:
> On Mon, Jun 27, 2016 at 10:54:07AM -0700, Tai Tri Nguyen wrote:
>> On Mon, Jun 27, 2016 at 9:00 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>>> On Sat, Jun 25, 2016 at 10:54:20AM -0700, Tai Tri Nguyen wrote:
>>>> On Thu, Jun 23, 2016 at 7:32 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>>>>> On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
>>>>>> +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
>>>>>> +{
>>>>>> + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
>>>>>> + struct xgene_pmu *xgene_pmu = dev_id;
>>>>>> + u32 val;
>>>>>> +
>>>>>> + xgene_pmu_mask_int(xgene_pmu);
>>>>>
>>>>> Why do you need to mask the IRQ? This handler is called in hard IRQ
>>>>> context.
>>>>
>>>> Right. Let me change to use raw_spin_lock_irqsave here.
>>>
>>> Interesting; I see we do that in the CCI PMU driver. What are we trying
>>> to protect?
>>>
>>> We don't do that in the CPU PMU drivers, and I'm missng something here.
>>> Hopefully I'm just being thick...
>>
>> For me, we can't guarantee that the interrupt doesn't happen on the other CPUs.
>> The irqbalancer may change the SMP affinity.
>
> The perf core requires things to occur on the same CPU for correct
> synchronisation.
>
> If an IRQ balancer can change the IRQ affinity behind our back, we have
> much bigger problems that affect other uncore PMU drivers.
>
> Marc, is there a sensible way to prevent irq balancers from changing the
> affinity of an IRQ, e.g. a kernel-side pinning mechanism, or some way we
> can be notified and reject changes?
You can get notified (see irq_set_affinity_notifier), but there no way
to veto the change. What should probably be done is to set the affinity
hint (irq_set_affinity_hint), and use the notifier to migrate the
context if possible. Note that you'll be called in process context,
which will race against interrupts being delivered on the new CPU.
M.
--
Jazz is not dead. It just smells funny...
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-28 13:21 ` Marc Zyngier
@ 2016-06-28 14:14 ` Mark Rutland
2016-06-28 16:39 ` Tai Tri Nguyen
0 siblings, 1 reply; 15+ messages in thread
From: Mark Rutland @ 2016-06-28 14:14 UTC (permalink / raw)
To: Marc Zyngier
Cc: Tai Tri Nguyen, Will Deacon, catalin.marinas, linux-kernel,
devicetree, linux-arm-kernel, patches
On Tue, Jun 28, 2016 at 02:21:38PM +0100, Marc Zyngier wrote:
> On 28/06/16 12:13, Mark Rutland wrote:
> > On Mon, Jun 27, 2016 at 10:54:07AM -0700, Tai Tri Nguyen wrote:
> >> On Mon, Jun 27, 2016 at 9:00 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> >>> On Sat, Jun 25, 2016 at 10:54:20AM -0700, Tai Tri Nguyen wrote:
> >>>> On Thu, Jun 23, 2016 at 7:32 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> >>>>> On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
> >>>>>> +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
> >>>>>> +{
> >>>>>> + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
> >>>>>> + struct xgene_pmu *xgene_pmu = dev_id;
> >>>>>> + u32 val;
> >>>>>> +
> >>>>>> + xgene_pmu_mask_int(xgene_pmu);
> >>>>>
> >>>>> Why do you need to mask the IRQ? This handler is called in hard IRQ
> >>>>> context.
> >>>>
> >>>> Right. Let me change to use raw_spin_lock_irqsave here.
> >>>
> >>> Interesting; I see we do that in the CCI PMU driver. What are we trying
> >>> to protect?
> >>>
> >>> We don't do that in the CPU PMU drivers, and I'm missng something here.
> >>> Hopefully I'm just being thick...
> >>
> >> For me, we can't guarantee that the interrupt doesn't happen on the other CPUs.
> >> The irqbalancer may change the SMP affinity.
> >
> > The perf core requires things to occur on the same CPU for correct
> > synchronisation.
> >
> > If an IRQ balancer can change the IRQ affinity behind our back, we have
> > much bigger problems that affect other uncore PMU drivers.
> >
> > Marc, is there a sensible way to prevent irq balancers from changing the
> > affinity of an IRQ, e.g. a kernel-side pinning mechanism, or some way we
> > can be notified and reject changes?
>
> You can get notified (see irq_set_affinity_notifier), but there no way
> to veto the change.
:(
> What should probably be done is to set the affinity hint
> (irq_set_affinity_hint), and use the notifier to migrate the context
> if possible. Note that you'll be called in process context, which will
> race against interrupts being delivered on the new CPU.
I'll have to go digging into what exactly perf_pmu_migrate_context
requires. Given the race, I'm not sure if that's going to work. It's
certainly not going to be self contained.
That also won't work for CPU PMUs, where it makes no sense to migrate
context or IRQs. For those we appear to already be using have
IRQF_NOBALANCING, which sounds like exactly what we want.
That appears to influence irq_can_set_affinity(), which the procfs
helpers check.
Tai, can you try requesting the IRQ with the IRQF_NOBALANCING flag?
Thanks,
Mark.
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-28 14:14 ` Mark Rutland
@ 2016-06-28 16:39 ` Tai Tri Nguyen
2016-06-28 16:59 ` Mark Rutland
0 siblings, 1 reply; 15+ messages in thread
From: Tai Tri Nguyen @ 2016-06-28 16:39 UTC (permalink / raw)
To: Mark Rutland
Cc: Marc Zyngier, Will Deacon, catalin.marinas, linux-kernel,
devicetree, linux-arm-kernel, patches
Hi Mark,
On Tue, Jun 28, 2016 at 7:14 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> On Tue, Jun 28, 2016 at 02:21:38PM +0100, Marc Zyngier wrote:
>> On 28/06/16 12:13, Mark Rutland wrote:
>> > On Mon, Jun 27, 2016 at 10:54:07AM -0700, Tai Tri Nguyen wrote:
>> >> On Mon, Jun 27, 2016 at 9:00 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>> >>> On Sat, Jun 25, 2016 at 10:54:20AM -0700, Tai Tri Nguyen wrote:
>> >>>> On Thu, Jun 23, 2016 at 7:32 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>> >>>>> On Wed, Jun 22, 2016 at 11:06:58AM -0700, Tai Nguyen wrote:
>> >>>>>> +static irqreturn_t xgene_pmu_isr(int irq, void *dev_id)
>> >>>>>> +{
>> >>>>>> + struct xgene_pmu_dev_ctx *ctx, *temp_ctx;
>> >>>>>> + struct xgene_pmu *xgene_pmu = dev_id;
>> >>>>>> + u32 val;
>> >>>>>> +
>> >>>>>> + xgene_pmu_mask_int(xgene_pmu);
>> >>>>>
>> >>>>> Why do you need to mask the IRQ? This handler is called in hard IRQ
>> >>>>> context.
>> >>>>
>> >>>> Right. Let me change to use raw_spin_lock_irqsave here.
>> >>>
>> >>> Interesting; I see we do that in the CCI PMU driver. What are we trying
>> >>> to protect?
>> >>>
>> >>> We don't do that in the CPU PMU drivers, and I'm missng something here.
>> >>> Hopefully I'm just being thick...
>> >>
>> >> For me, we can't guarantee that the interrupt doesn't happen on the other CPUs.
>> >> The irqbalancer may change the SMP affinity.
>> >
>> > The perf core requires things to occur on the same CPU for correct
>> > synchronisation.
>> >
>> > If an IRQ balancer can change the IRQ affinity behind our back, we have
>> > much bigger problems that affect other uncore PMU drivers.
>> >
>> > Marc, is there a sensible way to prevent irq balancers from changing the
>> > affinity of an IRQ, e.g. a kernel-side pinning mechanism, or some way we
>> > can be notified and reject changes?
>>
>> You can get notified (see irq_set_affinity_notifier), but there no way
>> to veto the change.
>
> :(
>
>> What should probably be done is to set the affinity hint
>> (irq_set_affinity_hint), and use the notifier to migrate the context
>> if possible. Note that you'll be called in process context, which will
>> race against interrupts being delivered on the new CPU.
>
> I'll have to go digging into what exactly perf_pmu_migrate_context
> requires. Given the race, I'm not sure if that's going to work. It's
> certainly not going to be self contained.
>
> That also won't work for CPU PMUs, where it makes no sense to migrate
> context or IRQs. For those we appear to already be using have
> IRQF_NOBALANCING, which sounds like exactly what we want.
>
> That appears to influence irq_can_set_affinity(), which the procfs
> helpers check.
>
> Tai, can you try requesting the IRQ with the IRQF_NOBALANCING flag?
This seems to work.
I also tried to change smp_affinity through procfs and it returns write error.
The interrupt seems to be excluded from irq balancing.
Should I make the change?
Thanks,
--
Tai
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-28 16:39 ` Tai Tri Nguyen
@ 2016-06-28 16:59 ` Mark Rutland
2016-06-28 18:05 ` Tai Tri Nguyen
0 siblings, 1 reply; 15+ messages in thread
From: Mark Rutland @ 2016-06-28 16:59 UTC (permalink / raw)
To: Tai Tri Nguyen
Cc: Marc Zyngier, Will Deacon, catalin.marinas, linux-kernel,
devicetree, linux-arm-kernel, patches
On Tue, Jun 28, 2016 at 09:39:36AM -0700, Tai Tri Nguyen wrote:
> Hi Mark,
>
> On Tue, Jun 28, 2016 at 7:14 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> > On Tue, Jun 28, 2016 at 02:21:38PM +0100, Marc Zyngier wrote:
> >> On 28/06/16 12:13, Mark Rutland wrote:
> >> > Marc, is there a sensible way to prevent irq balancers from changing the
> >> > affinity of an IRQ, e.g. a kernel-side pinning mechanism, or some way we
> >> > can be notified and reject changes?
> >>
> >> You can get notified (see irq_set_affinity_notifier), but there no way
> >> to veto the change.
> >
> > :(
> >
> >> What should probably be done is to set the affinity hint
> >> (irq_set_affinity_hint), and use the notifier to migrate the context
> >> if possible. Note that you'll be called in process context, which will
> >> race against interrupts being delivered on the new CPU.
> >
> > I'll have to go digging into what exactly perf_pmu_migrate_context
> > requires. Given the race, I'm not sure if that's going to work. It's
> > certainly not going to be self contained.
> >
> > That also won't work for CPU PMUs, where it makes no sense to migrate
> > context or IRQs. For those we appear to already be using have
> > IRQF_NOBALANCING, which sounds like exactly what we want.
> >
> > That appears to influence irq_can_set_affinity(), which the procfs
> > helpers check.
> >
> > Tai, can you try requesting the IRQ with the IRQF_NOBALANCING flag?
>
> This seems to work.
> I also tried to change smp_affinity through procfs and it returns write error.
> The interrupt seems to be excluded from irq balancing.
> Should I make the change?
Yes please. I believe you also need IRQF_NO_THREAD per the CPU PMU
drivers, so please add both flags. I'll do the same for the CCN and CCI
PMU drivers.
Thanks,
Mark.
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver
2016-06-28 16:59 ` Mark Rutland
@ 2016-06-28 18:05 ` Tai Tri Nguyen
0 siblings, 0 replies; 15+ messages in thread
From: Tai Tri Nguyen @ 2016-06-28 18:05 UTC (permalink / raw)
To: Mark Rutland
Cc: Marc Zyngier, Will Deacon, catalin.marinas, linux-kernel,
devicetree, linux-arm-kernel, patches
Hi Mark,
On Tue, Jun 28, 2016 at 9:59 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> On Tue, Jun 28, 2016 at 09:39:36AM -0700, Tai Tri Nguyen wrote:
>> Hi Mark,
>>
>> On Tue, Jun 28, 2016 at 7:14 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>> > On Tue, Jun 28, 2016 at 02:21:38PM +0100, Marc Zyngier wrote:
>> >> On 28/06/16 12:13, Mark Rutland wrote:
>> >> > Marc, is there a sensible way to prevent irq balancers from changing the
>> >> > affinity of an IRQ, e.g. a kernel-side pinning mechanism, or some way we
>> >> > can be notified and reject changes?
>> >>
>> >> You can get notified (see irq_set_affinity_notifier), but there no way
>> >> to veto the change.
>> >
>> > :(
>> >
>> >> What should probably be done is to set the affinity hint
>> >> (irq_set_affinity_hint), and use the notifier to migrate the context
>> >> if possible. Note that you'll be called in process context, which will
>> >> race against interrupts being delivered on the new CPU.
>> >
>> > I'll have to go digging into what exactly perf_pmu_migrate_context
>> > requires. Given the race, I'm not sure if that's going to work. It's
>> > certainly not going to be self contained.
>> >
>> > That also won't work for CPU PMUs, where it makes no sense to migrate
>> > context or IRQs. For those we appear to already be using have
>> > IRQF_NOBALANCING, which sounds like exactly what we want.
>> >
>> > That appears to influence irq_can_set_affinity(), which the procfs
>> > helpers check.
>> >
>> > Tai, can you try requesting the IRQ with the IRQF_NOBALANCING flag?
>>
>> This seems to work.
>> I also tried to change smp_affinity through procfs and it returns write error.
>> The interrupt seems to be excluded from irq balancing.
>> Should I make the change?
>
> Yes please. I believe you also need IRQF_NO_THREAD per the CPU PMU
> drivers, so please add both flags. I'll do the same for the CCN and CCI
> PMU drivers.
Btw, please skip the v5 I've sent out yesterday. I'll soon send the v6
with this change.
Thanks,
--
Tai
^ permalink raw reply [flat|nested] 15+ messages in thread
end of thread, other threads:[~2016-06-28 18:07 UTC | newest]
Thread overview: 15+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-06-22 18:06 [PATCH v4 0/4] perf: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 1/4] MAINTAINERS: Add entry for APM X-Gene SoC PMU driver Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 2/4] Documentation: Add documentation for APM X-Gene SoC PMU DTS binding Tai Nguyen
2016-06-22 18:06 ` [PATCH v4 3/4] perf: xgene: Add APM X-Gene SoC Performance Monitoring Unit driver Tai Nguyen
2016-06-23 14:32 ` Mark Rutland
2016-06-25 17:54 ` Tai Tri Nguyen
2016-06-27 16:00 ` Mark Rutland
2016-06-27 17:54 ` Tai Tri Nguyen
2016-06-28 11:13 ` Mark Rutland
2016-06-28 13:21 ` Marc Zyngier
2016-06-28 14:14 ` Mark Rutland
2016-06-28 16:39 ` Tai Tri Nguyen
2016-06-28 16:59 ` Mark Rutland
2016-06-28 18:05 ` Tai Tri Nguyen
2016-06-22 18:06 ` [PATCH v4 4/4] arm64: dts: apm: Add APM X-Gene SoC PMU DTS entries Tai Nguyen
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