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

On Thu, Jan 07, 2021 at 12:38:36PM +0000, Suzuki K Poulose wrote:

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@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com

---

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);
  

Stacking

• };
  

• };

+};

+#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)
  

Indentation

+{

• 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);
  

Stacking

+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)
  

Stacking

I did the changes while applying to my tree - please address if you end up re-spinning.

+{ +}

+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