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From: Suzuki K Poulose <suzuki.poulose@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: mathieu.poirier@linaro.org,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	coresight@lists.linaro.org, Anshuman.Khandual@arm.com,
	leo.yan@linaro.org, mike.leach@linaro.org
Subject: [PATCH 01/19] coresight: Introduce device access abstraction
Date: Fri, 11 Sep 2020 09:41:01 +0100	[thread overview]
Message-ID: <20200911084119.1080694-2-suzuki.poulose@arm.com> (raw)
In-Reply-To: <20200911084119.1080694-1-suzuki.poulose@arm.com>

We are about to introduce support for sysreg access to ETMv4.4+
component. Since there are generic routines that access the
registers (e.g, CS_LOCK/UNLOCK , claim/disclaim operations, timeout)
and in order to preserve the logic of these operations at a
single place we introduce an abstraction layer for the accesses
to a given device.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 drivers/hwtracing/coresight/coresight-catu.c  |   1 +
 drivers/hwtracing/coresight/coresight-cti.c   |   1 +
 drivers/hwtracing/coresight/coresight-etb10.c |   1 +
 drivers/hwtracing/coresight/coresight-etm3x.c |   1 +
 drivers/hwtracing/coresight/coresight-etm4x.c |   1 +
 .../hwtracing/coresight/coresight-funnel.c    |   1 +
 .../coresight/coresight-replicator.c          |   1 +
 drivers/hwtracing/coresight/coresight-stm.c   |   1 +
 drivers/hwtracing/coresight/coresight-tmc.c   |   1 +
 drivers/hwtracing/coresight/coresight-tpiu.c  |   1 +
 drivers/hwtracing/coresight/coresight.c       |  49 +++++
 include/linux/coresight.h                     | 197 ++++++++++++++++++
 12 files changed, 256 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
index 1801804a7762..90da0b842717 100644
--- a/drivers/hwtracing/coresight/coresight-catu.c
+++ b/drivers/hwtracing/coresight/coresight-catu.c
@@ -551,6 +551,7 @@ static int catu_probe(struct amba_device *adev, const struct amba_id *id)
 	dev->platform_data = pdata;
 
 	drvdata->base = base;
+	catu_desc.access = CSDEV_ACCESS_IOMEM(base);
 	catu_desc.pdata = pdata;
 	catu_desc.dev = dev;
 	catu_desc.groups = catu_groups;
diff --git a/drivers/hwtracing/coresight/coresight-cti.c b/drivers/hwtracing/coresight/coresight-cti.c
index 47f3c9abae30..e13e24e4a858 100644
--- a/drivers/hwtracing/coresight/coresight-cti.c
+++ b/drivers/hwtracing/coresight/coresight-cti.c
@@ -849,6 +849,7 @@ static int cti_probe(struct amba_device *adev, const struct amba_id *id)
 		return PTR_ERR(base);
 
 	drvdata->base = base;
+	cti_desc.access = CSDEV_ACCESS_IOMEM(base);
 
 	dev_set_drvdata(dev, drvdata);
 
diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 03e3f2590191..42fe174a68f0 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -755,6 +755,7 @@ static int etb_probe(struct amba_device *adev, const struct amba_id *id)
 		return PTR_ERR(base);
 
 	drvdata->base = base;
+	desc.access = CSDEV_ACCESS_IOMEM(base);
 
 	spin_lock_init(&drvdata->spinlock);
 
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index bf22dcfd3327..e3724d8adecb 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -805,6 +805,7 @@ static int etm_probe(struct amba_device *adev, const struct amba_id *id)
 		return PTR_ERR(base);
 
 	drvdata->base = base;
+	desc.access = CSDEV_ACCESS_IOMEM(base);
 
 	spin_lock_init(&drvdata->spinlock);
 
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 00c9f0bb8b1a..466e6f304751 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -1488,6 +1488,7 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
 		return PTR_ERR(base);
 
 	drvdata->base = base;
+	desc.access = CSDEV_ACCESS_IOMEM(base);
 
 	spin_lock_init(&drvdata->spinlock);
 
diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c
index 900690a9f7f0..e8e233cbc130 100644
--- a/drivers/hwtracing/coresight/coresight-funnel.c
+++ b/drivers/hwtracing/coresight/coresight-funnel.c
@@ -242,6 +242,7 @@ static int funnel_probe(struct device *dev, struct resource *res)
 		}
 		drvdata->base = base;
 		desc.groups = coresight_funnel_groups;
+		desc.access = CSDEV_ACCESS_IOMEM(base);
 	}
 
 	dev_set_drvdata(dev, drvdata);
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
index 78acf29c49ca..8ba9cbe1d108 100644
--- a/drivers/hwtracing/coresight/coresight-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-replicator.c
@@ -254,6 +254,7 @@ static int replicator_probe(struct device *dev, struct resource *res)
 		}
 		drvdata->base = base;
 		desc.groups = replicator_groups;
+		desc.access = CSDEV_ACCESS_IOMEM(base);
 	}
 
 	if (fwnode_property_present(dev_fwnode(dev),
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index 2ba819a47cf6..fbf86f31f2ab 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -884,6 +884,7 @@ static int stm_probe(struct amba_device *adev, const struct amba_id *id)
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 	drvdata->base = base;
+	desc.access = CSDEV_ACCESS_IOMEM(base);
 
 	ret = stm_get_stimulus_area(dev, &ch_res);
 	if (ret)
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index 7040d583bed9..5711e55c310c 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -458,6 +458,7 @@ static int tmc_probe(struct amba_device *adev, const struct amba_id *id)
 	}
 
 	drvdata->base = base;
+	desc.access = CSDEV_ACCESS_IOMEM(base);
 
 	spin_lock_init(&drvdata->spinlock);
 
diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
index f8583e4032a6..4eb3f50618b6 100644
--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -149,6 +149,7 @@ static int tpiu_probe(struct amba_device *adev, const struct amba_id *id)
 		return PTR_ERR(base);
 
 	drvdata->base = base;
+	desc.access = CSDEV_ACCESS_IOMEM(base);
 
 	/* Disable tpiu to support older devices */
 	tpiu_disable_hw(drvdata);
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index e9c90f2de34a..38e9c03ab754 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -1387,6 +1387,54 @@ static int __init coresight_init(void)
 }
 postcore_initcall(coresight_init);
 
+u32 coresight_relaxed_read32(struct coresight_device *csdev, u32 offset)
+{
+	return csdev_access_relaxed_read32(&csdev->access, offset);
+}
+
+u32 coresight_read32(struct coresight_device *csdev, u32 offset)
+{
+	return csdev_access_read32(&csdev->access, offset);
+}
+
+void coresight_relaxed_write32(struct coresight_device *csdev,
+			       u32 val,
+			       u32 offset)
+{
+
+	csdev_access_relaxed_write32(&csdev->access, val, offset);
+}
+
+
+void coresight_write32(struct coresight_device *csdev, u32 val, u32 offset)
+{
+	csdev_access_write32(&csdev->access, val, offset);
+}
+
+u64 coresight_relaxed_read64(struct coresight_device *csdev, u32 offset)
+{
+	return csdev_access_relaxed_read64(&csdev->access, offset);
+}
+
+u64 coresight_read64(struct coresight_device *csdev, u32 offset)
+{
+	return csdev_access_read64(&csdev->access, offset);
+}
+
+void coresight_relaxed_write64(struct coresight_device *csdev,
+			       u64 val,
+			       u32 offset)
+{
+
+	csdev_access_relaxed_write64(&csdev->access, val, offset);
+}
+
+
+void coresight_write64(struct coresight_device *csdev, u64 val, u32 offset)
+{
+	csdev_access_write64(&csdev->access, val, offset);
+}
+
 /*
  * coresight_release_platform_data: Release references to the devices connected
  * to the output port of this device.
@@ -1451,6 +1499,7 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 	csdev->type = desc->type;
 	csdev->subtype = desc->subtype;
 	csdev->ops = desc->ops;
+	csdev->access = desc->access;
 	csdev->orphan = false;
 
 	csdev->dev.type = &coresight_dev_type[desc->type];
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 58fffdecdbfd..1377240275d8 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -7,6 +7,7 @@
 #define _LINUX_CORESIGHT_H
 
 #include <linux/device.h>
+#include <linux/io.h>
 #include <linux/perf_event.h>
 #include <linux/sched.h>
 
@@ -114,6 +115,38 @@ struct coresight_platform_data {
 	struct coresight_connection *conns;
 };
 
+/**
+ * struct csdev_access - Abstraction of a CoreSight device access.
+ *
+ * @io_mem	: True if the device has memory mapped I/O
+ * @base	: When io_mem == true, base address of the component
+ * @read	: Read from the given "offset" of the given instance.
+ * @write	: Write "val" to the given "offset".
+ */
+struct csdev_access {
+	bool io_mem;
+	union {
+		void __iomem *base;
+		struct {
+			u64 (*read)(struct csdev_access *csa,
+				    u32 offset,
+				    bool relaxed,
+				    bool _64bit);
+			void (*write)(struct csdev_access *csa,
+				      u64 val,
+				      u32 offset,
+				      bool relaxed,
+				      bool _64bit);
+		};
+	};
+};
+
+#define CSDEV_ACCESS_IOMEM(addr)		\
+	(struct csdev_access)	{		\
+		.io_mem		= true,		\
+		.base		= addr,		\
+	}
+
 /**
  * struct coresight_desc - description of a component required from drivers
  * @type:	as defined by @coresight_dev_type.
@@ -125,6 +158,7 @@ struct coresight_platform_data {
  * @groups:	operations specific to this component. These will end up
  *		in the component's sysfs sub-directory.
  * @name:	name for the coresight device, also shown under sysfs.
+ * @access:	Describe access to the device
  */
 struct coresight_desc {
 	enum coresight_dev_type type;
@@ -134,6 +168,7 @@ struct coresight_desc {
 	struct device *dev;
 	const struct attribute_group **groups;
 	const char *name;
+	struct csdev_access access;
 };
 
 /**
@@ -186,6 +221,7 @@ struct coresight_sysfs_link {
  * @def_sink:	cached reference to default sink found for this device.
  * @ect_dev:	Associated cross trigger device. Not part of the trace data
  *		path or connections.
+ * @access:	Device i/o access abstraction for this device.
  * @nr_links:   number of sysfs links created to other components from this
  *		device. These will appear in the "connections" group.
  * @has_conns_grp: Have added a "connections" group for sysfs links.
@@ -205,6 +241,7 @@ struct coresight_device {
 	struct coresight_device *def_sink;
 	/* cross trigger handling */
 	struct coresight_device *ect_dev;
+	struct csdev_access access;
 	/* sysfs links between components */
 	int nr_links;
 	bool has_conns_grp;
@@ -324,6 +361,107 @@ struct coresight_ops {
 	const struct coresight_ops_ect *ect_ops;
 };
 
+static inline u32 csdev_access_relaxed_read32(struct csdev_access *csa,
+					      u32 offset)
+{
+	if (likely(csa->io_mem))
+		return readl_relaxed(csa->base + offset);
+
+	return csa->read(csa, offset, true, false);
+}
+
+static inline u32 csdev_access_read32(struct csdev_access *csa, u32 offset)
+{
+	if (likely(csa->io_mem))
+		return readl(csa->base + offset);
+
+	return csa->read(csa, offset, false, false);
+}
+
+static inline void csdev_access_relaxed_write32(struct csdev_access *csa,
+						u32 val,
+						u32 offset)
+{
+	if (likely(csa->io_mem))
+		writel_relaxed(val, csa->base + offset);
+	else
+		csa->write(csa, val, offset, true, false);
+}
+
+static inline void csdev_access_write32(struct csdev_access *csa, u32 val, u32 offset)
+{
+	if (likely(csa->io_mem))
+		writel(val, csa->base + offset);
+	else
+		csa->write(csa, val, offset, false, false);
+}
+
+#ifdef CONFIG_64BIT
+
+static inline u64 csdev_access_relaxed_read64(struct csdev_access *csa,
+					   u32 offset)
+{
+	if (likely(csa->io_mem))
+		return readq_relaxed(csa->base + offset);
+
+	return csa->read(csa, offset, true, true);
+}
+
+static inline u64 csdev_access_read64(struct csdev_access *csa, u32 offset)
+{
+	if (likely(csa->io_mem))
+		return readq(csa->base + offset);
+
+	return csa->read(csa, offset, false, true);
+}
+
+static inline void csdev_access_relaxed_write64(struct csdev_access *csa,
+						u64 val,
+						u32 offset)
+{
+	if (likely(csa->io_mem))
+		writeq_relaxed(val, csa->base + offset);
+	else
+		csa->write(csa, val, offset, true, true);
+}
+
+static inline void csdev_access_write64(struct csdev_access *csa, u64 val, u32 offset)
+{
+	if (likely(csa->io_mem))
+		writeq(val, csa->base + offset);
+	else
+		csa->write(csa, val, offset, false, true);
+}
+
+#else
+
+static inline u64 csdev_access_relaxed_read64(struct csdev_access *csa,
+					   u32 offset)
+{
+	WARN_ON(1);
+	return 0;
+}
+
+static inline u64 csdev_access_read64(struct csdev_access *csa, u32 offset)
+{
+	WARN_ON(1);
+	return 0;
+}
+
+static inline void csdev_access_relaxed_write64(struct csdev_access *csa,
+						u64 val,
+						u32 offset)
+{
+	WARN_ON(1);
+}
+
+static inline void csdev_access_write64(struct csdev_access *csa, u64 val, u32 offset)
+{
+	WARN_ON(1);
+}
+#endif
+
+
 #ifdef CONFIG_CORESIGHT
 extern struct coresight_device *
 coresight_register(struct coresight_desc *desc);
@@ -342,6 +480,20 @@ extern char *coresight_alloc_device_name(struct coresight_dev_list *devs,
 					 struct device *dev);
 
 extern bool coresight_loses_context_with_cpu(struct device *dev);
+
+u32 coresight_relaxed_read32(struct coresight_device *csdev, u32 offset);
+u32 coresight_read32(struct coresight_device *csdev, u32 offset);
+void coresight_write32(struct coresight_device *csdev, u32 val, u32 offset);
+void coresight_relaxed_write32(struct coresight_device *csdev,
+			       u32 val,
+			       u32 offset);
+u64 coresight_relaxed_read64(struct coresight_device *csdev, u32 offset);
+u64 coresight_read64(struct coresight_device *csdev, u32 offset);
+void coresight_relaxed_write64(struct coresight_device *csdev,
+			       u64 val, u32 offset);
+void coresight_write64(struct coresight_device *csdev, u64 val, u32 offset);
+
+
 #else
 static inline struct coresight_device *
 coresight_register(struct coresight_desc *desc) { return NULL; }
@@ -368,6 +520,51 @@ static inline bool coresight_loses_context_with_cpu(struct device *dev)
 {
 	return false;
 }
+
+static inline u32 coresight_relaxed_read32(struct coresight_device *csdev, u32 offset)
+{
+	WARN_ON_ONCE(1);
+	return 0;
+}
+
+static inline u32 coresight_read32(struct coresight_device *csdev, u32 offset)
+{
+	WARN_ON_ONCE(1);
+	return 0;
+}
+
+static inline void coresight_write32(struct coresight_device *csdev, u32 val, u32 offset)
+{
+}
+
+static inline void coresight_relaxed_write32(struct coresight_device *csdev,
+					      u32 val, u32 offset);
+{
+}
+
+static inline u64 coresight_relaxed_read64(struct coresight_device *csdev,
+					   u32 offset)
+{
+	WARN_ON_ONCE(1);
+	return 0;
+}
+
+static inline u64 coresight_read64(struct coresight_device *csdev, u32 offset)
+{
+	WARN_ON_ONCE(1);
+	return 0;
+}
+
+static inline void coresight_relaxed_write64(struct coresight_device *csdev,
+					     u64 val,
+					     u32 offset)
+{
+}
+
+static inline void coresight_write64(struct coresight_device *csdev, u64 val, u32 offset)
+{
+}
+
 #endif
 
 extern int coresight_get_cpu(struct device *dev);
-- 
2.24.1


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  reply	other threads:[~2020-09-11  8:43 UTC|newest]

Thread overview: 54+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-11  8:41 [PATCH 00/19] coresight: Support for ETMv4.4 system instructions Suzuki K Poulose
2020-09-11  8:41 ` Suzuki K Poulose [this message]
2020-09-18 15:33   ` [PATCH 01/19] coresight: Introduce device access abstraction Mike Leach
2020-09-11  8:41 ` [PATCH 02/19] coresight: tpiu: Prepare for using coresight " Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-11  8:41 ` [PATCH 03/19] coresight: Convert coresight_timeout to use " Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-11  8:41 ` [PATCH 04/19] coresight: Convert claim/disclaim operations to use access wrappers Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-11  8:41 ` [PATCH 05/19] coresight: Use device access layer for Software lock/unlock operations Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-18 15:52     ` Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 06/19] coresight: etm4x: Always read the registers on the host CPU Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-11  8:41 ` [PATCH 07/19] coresight: etm4x: Convert all register accesses Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-11  8:41 ` [PATCH 08/19] coresight: etm4x: Add commentary on the registers Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-11  8:41 ` [PATCH 09/19] coresight: etm4x: Add sysreg access helpers Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-11  8:41 ` [PATCH 10/19] coresight: etm4x: Define DEVARCH register fields Suzuki K Poulose
2020-09-18 15:34   ` Mike Leach
2020-09-22 10:20     ` Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 11/19] coresight: etm4x: Check for OS and Software Lock Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-22 10:44     ` Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 12/19] coresight: etm4x: Cleanup secure exception level masks Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-22 10:55     ` Suzuki K Poulose
2020-09-22 12:47       ` Mike Leach
2020-09-30 10:32         ` Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 13/19] coresight: etm4x: Clean up " Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-22 10:59     ` Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 14/19] coresight: etm4x: Detect access early on the target CPU Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 15/19] coresight: etm4x: Use TRCDEVARCH for component discovery Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-22 11:18     ` Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 16/19] coresight: etm4x: Detect system instructions support Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-22 11:59     ` Suzuki K Poulose
2020-09-11  8:41 ` [PATCH 17/19] coresight: etm4x: Refactor probing routine Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-11  8:41 ` [PATCH 18/19] coresight: etm4x: Add support for sysreg only devices Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-23 11:52     ` Suzuki K Poulose
2020-09-23 16:55       ` Mike Leach
2020-09-11  8:41 ` [PATCH 19/19] dts: bindings: coresight: ETMv4.4 system register access only units Suzuki K Poulose
2020-09-18 15:35   ` Mike Leach
2020-09-24  9:48     ` Suzuki K Poulose
2020-09-24 10:08       ` Mike Leach
2020-09-18 15:33 ` [PATCH 00/19] coresight: Support for ETMv4.4 system instructions Mike Leach
2020-09-25  9:55   ` Suzuki K Poulose
2020-09-29 16:42     ` Mike Leach

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    --in-reply-to=20200911084119.1080694-2-suzuki.poulose@arm.com \
    --to=suzuki.poulose@arm.com \
    --cc=Anshuman.Khandual@arm.com \
    --cc=coresight@lists.linaro.org \
    --cc=leo.yan@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=mathieu.poirier@linaro.org \
    --cc=mike.leach@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

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