[PATCH V3 05/14] coresight: ete: Add support for ETE tracing

From: Anshuman Khandual
Date: Wed Jan 27 2021 - 04:48:57 EST


From: Suzuki K Poulose <suzuki.poulose@xxxxxxx>

Add ETE as one of the supported device types we support
with ETM4x driver. The devices are named following the
existing convention as ete<N>.

ETE mandates that the trace resource status register is programmed
before the tracing is turned on. For the moment simply write to
it indicating TraceActive.

Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Mike Leach <mike.leach@xxxxxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
drivers/hwtracing/coresight/Kconfig | 10 ++--
drivers/hwtracing/coresight/coresight-etm4x-core.c | 56 +++++++++++++++++-----
.../hwtracing/coresight/coresight-etm4x-sysfs.c | 19 ++++++--
drivers/hwtracing/coresight/coresight-etm4x.h | 16 ++++++-
4 files changed, 79 insertions(+), 22 deletions(-)

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 7b44ba2..f154ae7 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -97,15 +97,15 @@ config CORESIGHT_SOURCE_ETM3X
module will be called coresight-etm3x.

config CORESIGHT_SOURCE_ETM4X
- tristate "CoreSight Embedded Trace Macrocell 4.x driver"
+ tristate "CoreSight ETMv4.x / ETE driver"
depends on ARM64
select CORESIGHT_LINKS_AND_SINKS
select PID_IN_CONTEXTIDR
help
- This driver provides support for the ETM4.x tracer module, tracing the
- instructions that a processor is executing. This is primarily useful
- for instruction level tracing. Depending on the implemented version
- data tracing may also be available.
+ This driver provides support for the CoreSight Embedded Trace Macrocell
+ version 4.x and the Embedded Trace Extensions (ETE). Both are CPU tracer
+ modules, tracing the instructions that a processor is executing. This is
+ primarily useful for instruction level tracing.

To compile this driver as a module, choose M here: the
module will be called coresight-etm4x.
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 9e92d2a..b40e3c2 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -431,6 +431,13 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
etm4x_relaxed_write32(csa, trcpdcr | TRCPDCR_PU, TRCPDCR);
}

+ /*
+ * ETE mandates that the TRCRSR is written to before
+ * enabling it.
+ */
+ if (etm4x_is_ete(drvdata))
+ etm4x_relaxed_write32(csa, TRCRSR_TA, TRCRSR);
+
/* Enable the trace unit */
etm4x_relaxed_write32(csa, 1, TRCPRGCTLR);

@@ -864,13 +871,24 @@ static bool etm4_init_sysreg_access(struct etmv4_drvdata *drvdata,
* ETMs implementing sysreg access must implement TRCDEVARCH.
*/
devarch = read_etm4x_sysreg_const_offset(TRCDEVARCH);
- if ((devarch & ETM_DEVARCH_ID_MASK) != ETM_DEVARCH_ETMv4x_ARCH)
+ switch (devarch & ETM_DEVARCH_ID_MASK) {
+ case ETM_DEVARCH_ETMv4x_ARCH:
+ *csa = (struct csdev_access) {
+ .io_mem = false,
+ .read = etm4x_sysreg_read,
+ .write = etm4x_sysreg_write,
+ };
+ break;
+ case ETM_DEVARCH_ETE_ARCH:
+ *csa = (struct csdev_access) {
+ .io_mem = false,
+ .read = ete_sysreg_read,
+ .write = ete_sysreg_write,
+ };
+ break;
+ default:
return false;
- *csa = (struct csdev_access) {
- .io_mem = false,
- .read = etm4x_sysreg_read,
- .write = etm4x_sysreg_write,
- };
+ }

drvdata->arch = etm_devarch_to_arch(devarch);
return true;
@@ -1808,6 +1826,8 @@ static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid)
struct etmv4_drvdata *drvdata;
struct coresight_desc desc = { 0 };
struct etm4_init_arg init_arg = { 0 };
+ u8 major, minor;
+ char *type_name;

drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
@@ -1834,10 +1854,6 @@ static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid)
if (drvdata->cpu < 0)
return drvdata->cpu;

- desc.name = devm_kasprintf(dev, GFP_KERNEL, "etm%d", drvdata->cpu);
- if (!desc.name)
- return -ENOMEM;
-
init_arg.drvdata = drvdata;
init_arg.csa = &desc.access;
init_arg.pid = etm_pid;
@@ -1853,6 +1869,20 @@ static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid)
if (!desc.access.io_mem ||
fwnode_property_present(dev_fwnode(dev), "qcom,skip-power-up"))
drvdata->skip_power_up = true;
+ major = ETM_ARCH_MAJOR_VERSION(drvdata->arch);
+ minor = ETM_ARCH_MINOR_VERSION(drvdata->arch);
+ if (etm4x_is_ete(drvdata)) {
+ type_name = "ete";
+ /* ETE v1 has major version == 5. Adjust this for logging.*/
+ major -= 4;
+ } else {
+ type_name = "etm";
+ }
+
+ desc.name = devm_kasprintf(dev, GFP_KERNEL,
+ "%s%d", type_name, drvdata->cpu);
+ if (!desc.name)
+ return -ENOMEM;

etm4_init_trace_id(drvdata);
etm4_set_default(&drvdata->config);
@@ -1881,9 +1911,8 @@ static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid)

etmdrvdata[drvdata->cpu] = drvdata;

- dev_info(&drvdata->csdev->dev, "CPU%d: ETM v%d.%d initialized\n",
- drvdata->cpu, ETM_ARCH_MAJOR_VERSION(drvdata->arch),
- ETM_ARCH_MINOR_VERSION(drvdata->arch));
+ dev_info(&drvdata->csdev->dev, "CPU%d: %s v%d.%d initialized\n",
+ drvdata->cpu, type_name, major, minor);

if (boot_enable) {
coresight_enable(drvdata->csdev);
@@ -2027,6 +2056,7 @@ static struct amba_driver etm4x_amba_driver = {

static const struct of_device_id etm4_sysreg_match[] = {
{ .compatible = "arm,coresight-etm4x-sysreg" },
+ { .compatible = "arm,embedded-trace-extension" },
{}
};

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
index b646d53..1c490bc 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
@@ -2374,12 +2374,20 @@ static inline bool
etm4x_register_implemented(struct etmv4_drvdata *drvdata, u32 offset)
{
switch (offset) {
- ETM4x_SYSREG_LIST_CASES
+ ETM_COMMON_SYSREG_LIST_CASES
/*
- * Registers accessible via system instructions are always
- * implemented.
+ * Common registers to ETE & ETM4x accessible via system
+ * instructions are always implemented.
*/
return true;
+
+ ETM4x_ONLY_SYSREG_LIST_CASES
+ /*
+ * We only support etm4x and ete. So if the device is not
+ * ETE, it must be ETMv4x.
+ */
+ return !etm4x_is_ete(drvdata);
+
ETM4x_MMAP_LIST_CASES
/*
* Registers accessible only via memory-mapped registers
@@ -2389,8 +2397,13 @@ etm4x_register_implemented(struct etmv4_drvdata *drvdata, u32 offset)
* coresight_register() and the csdev is not initialized
* until that is done. So rely on the drvdata->base to
* detect if we have a memory mapped access.
+ * Also ETE doesn't implement memory mapped access, thus
+ * it is sufficient to check that we are using mmio.
*/
return !!drvdata->base;
+
+ ETE_ONLY_SYSREG_LIST_CASES
+ return etm4x_is_ete(drvdata);
}

return false;
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
index ca24ac5..8b90de5 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.h
+++ b/drivers/hwtracing/coresight/coresight-etm4x.h
@@ -128,6 +128,8 @@
#define TRCCIDR2 0xFF8
#define TRCCIDR3 0xFFC

+#define TRCRSR_TA BIT(12)
+
/*
* System instructions to access ETM registers.
* See ETMv4.4 spec ARM IHI0064F section 4.3.6 System instructions
@@ -390,6 +392,9 @@
#define ETM_COMMON_SYSREG_LIST_CASES \
ETM_COMMON_SYSREG_LIST(NOP, __unused)

+#define ETM4x_ONLY_SYSREG_LIST_CASES \
+ ETM4x_ONLY_SYSREG_LIST(NOP, __unused)
+
#define ETM4x_SYSREG_LIST_CASES \
ETM_COMMON_SYSREG_LIST_CASES \
ETM4x_ONLY_SYSREG_LIST(NOP, __unused)
@@ -406,7 +411,6 @@
ETE_ONLY_SYSREG_LIST(WRITE, (val))

#define ETE_ONLY_SYSREG_LIST_CASES \
- ETM_COMMON_SYSREG_LIST_CASES \
ETE_ONLY_SYSREG_LIST(NOP, __unused)

#define read_etm4x_sysreg_offset(offset, _64bit) \
@@ -589,11 +593,14 @@
((ETM_DEVARCH_MAKE_ARCHID_ARCH_VER(major)) | ETM_DEVARCH_ARCHID_ARCH_PART(0xA13))

#define ETM_DEVARCH_ARCHID_ETMv4x ETM_DEVARCH_MAKE_ARCHID(0x4)
+#define ETM_DEVARCH_ARCHID_ETE ETM_DEVARCH_MAKE_ARCHID(0x5)

#define ETM_DEVARCH_ID_MASK \
(ETM_DEVARCH_ARCHITECT_MASK | ETM_DEVARCH_ARCHID_MASK | ETM_DEVARCH_PRESENT)
#define ETM_DEVARCH_ETMv4x_ARCH \
(ETM_DEVARCH_ARCHITECT_ARM | ETM_DEVARCH_ARCHID_ETMv4x | ETM_DEVARCH_PRESENT)
+#define ETM_DEVARCH_ETE_ARCH \
+ (ETM_DEVARCH_ARCHITECT_ARM | ETM_DEVARCH_ARCHID_ETE | ETM_DEVARCH_PRESENT)

#define TRCSTATR_IDLE_BIT 0
#define TRCSTATR_PMSTABLE_BIT 1
@@ -683,6 +690,8 @@
#define ETM_ARCH_MINOR_VERSION(arch) ((arch) & 0xfU)

#define ETM_ARCH_V4 ETM_ARCH_VERSION(4, 0)
+#define ETM_ARCH_ETE ETM_ARCH_VERSION(5, 0)
+
/* Interpretation of resource numbers change at ETM v4.3 architecture */
#define ETM_ARCH_V4_3 ETM_ARCH_VERSION(4, 3)

@@ -989,4 +998,9 @@ void etm4_config_trace_mode(struct etmv4_config *config);

u64 etm4x_sysreg_read(u32 offset, bool _relaxed, bool _64bit);
void etm4x_sysreg_write(u64 val, u32 offset, bool _relaxed, bool _64bit);
+
+static inline bool etm4x_is_ete(struct etmv4_drvdata *drvdata)
+{
+ return drvdata->arch >= ETM_ARCH_ETE;
+}
#endif
--
2.7.4