[PATCH v6 03/26] coresight: Introduce device access abstraction

From: Suzuki K Poulose
Date: Thu Jan 07 2021 - 07:40:36 EST


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: Mike Leach <mike.leach@xxxxxxxxxx>
Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
Change since v3
- Dropped csa argument to read()/write().
- Addressed comments on spacing and adding labels for the #if #else #endifs.
(Mathieu)
---
drivers/hwtracing/coresight/coresight-catu.c | 1 +
drivers/hwtracing/coresight/coresight-core.c | 43 ++++
.../hwtracing/coresight/coresight-cti-core.c | 1 +
drivers/hwtracing/coresight/coresight-etb10.c | 1 +
.../coresight/coresight-etm3x-core.c | 1 +
.../coresight/coresight-etm4x-core.c | 1 +
.../hwtracing/coresight/coresight-funnel.c | 1 +
.../coresight/coresight-replicator.c | 1 +
drivers/hwtracing/coresight/coresight-stm.c | 1 +
.../hwtracing/coresight/coresight-tmc-core.c | 1 +
drivers/hwtracing/coresight/coresight-tpiu.c | 1 +
include/linux/coresight.h | 198 +++++++++++++++++-
12 files changed, 248 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
index a61313f320bd..867c932c7b26 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-core.c b/drivers/hwtracing/coresight/coresight-core.c
index 4ba801dffcb7..a38af8f0831b 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -1458,6 +1458,48 @@ int coresight_timeout(void __iomem *addr, u32 offset, int position, int value)
}
EXPORT_SYMBOL_GPL(coresight_timeout);

+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.
@@ -1522,6 +1564,7 @@ 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/drivers/hwtracing/coresight/coresight-cti-core.c b/drivers/hwtracing/coresight/coresight-cti-core.c
index 61dbc1afd8da..b38a8db5f252 100644
--- a/drivers/hwtracing/coresight/coresight-cti-core.c
+++ b/drivers/hwtracing/coresight/coresight-cti-core.c
@@ -870,6 +870,7 @@ 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 0cf6f0b947b6..cc742561a986 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -757,6 +757,7 @@ 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-core.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c
index 5bf5a5a4ce6d..3b7837cbe376 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c
@@ -839,6 +839,7 @@ 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-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index cce65fc0c9aa..ebd41bb7ce1c 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -1626,6 +1626,7 @@ 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 071c723227db..8f7c40d7d8d6 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 7e2a2b7f503f..205756fab729 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 99791773f682..41d9a922c2d4 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-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index 8169dff5a9f6..e61b75be66b6 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-core.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -456,6 +456,7 @@ 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 d5dfee9ee556..6ca396799883 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/include/linux/coresight.h b/include/linux/coresight.h
index 7d3c87e5b97c..d3aa328639cd 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 +115,36 @@ 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)(u32 offset,
+ bool relaxed,
+ bool _64bit);
+ void (*write)(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 +156,7 @@ 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 +166,7 @@ struct coresight_desc {
struct device *dev;
const struct attribute_group **groups;
const char *name;
+ struct csdev_access access;
};

/**
@@ -173,7 +206,8 @@ struct coresight_sysfs_link {
* @type: as defined by @coresight_dev_type.
* @subtype: as defined by @coresight_dev_subtype.
* @ops: generic operations for this component, as defined
- by @coresight_ops.
+ * by @coresight_ops.
+ * @access: Device i/o access abstraction for this device.
* @dev: The device entity associated to this component.
* @refcnt: keep track of what is in use.
* @orphan: true if the component has connections that haven't been linked.
@@ -195,6 +229,7 @@ struct coresight_device {
enum coresight_dev_type type;
union coresight_dev_subtype subtype;
const struct coresight_ops *ops;
+ struct csdev_access access;
struct device dev;
atomic_t *refcnt;
bool orphan;
@@ -326,6 +361,104 @@ struct coresight_ops {
};

#if IS_ENABLED(CONFIG_CORESIGHT)
+
+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(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(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(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(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(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(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(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(val, offset, false, true);
+}
+
+#else /* !CONFIG_64BIT */
+
+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 /* CONFIG_64BIT */
+
extern struct coresight_device *
coresight_register(struct coresight_desc *desc);
extern void coresight_unregister(struct coresight_device *csdev);
@@ -343,6 +476,20 @@ 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; }
@@ -369,10 +516,55 @@ static inline bool coresight_loses_context_with_cpu(struct device *dev)
{
return false;
}
-#endif
+
+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 /* IS_ENABLED(CONFIG_CORESIGHT) */

extern int coresight_get_cpu(struct device *dev);

struct coresight_platform_data *coresight_get_platform_data(struct device *dev);

-#endif
+#endif /* _LINUX_COREISGHT_H */
--
2.24.1