[PATCH 3/6] coresight: Introduce support for Coresight Address Translation Unit

From: Suzuki K Poulose
Date: Mon Jun 18 2018 - 06:57:28 EST


Add the initial support for Coresight Address Translation Unit, which
augments the TMC in Coresight SoC-600 by providing an improved Scatter
Gather mechanism. CATU is always connected to a single TMC-ETR and
converts the AXI address with a translated address (from a given SG
table with specific format). The CATU should be programmed in pass
through mode and enabled if the ETR doesn't translation by CATU.

This patch provides mechanism to enable/disable the CATU always in the
pass through mode.

We reuse the existing ports mechanism to link the TMC-ETR to the
connected CATU.

i.e, TMC-ETR:output_port0 -> CATU:input_port0

Reference manual for CATU component is avilable in version r2p0 of :
"Arm Coresight System-on-Chip SoC-600 Technical Reference Manual".

Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
drivers/hwtracing/coresight/Kconfig | 11 ++
drivers/hwtracing/coresight/Makefile | 1 +
drivers/hwtracing/coresight/coresight-catu.c | 214 ++++++++++++++++++++++++
drivers/hwtracing/coresight/coresight-catu.h | 85 ++++++++++
drivers/hwtracing/coresight/coresight-tmc-etr.c | 52 ++++++
include/linux/coresight.h | 1 +
6 files changed, 364 insertions(+)
create mode 100644 drivers/hwtracing/coresight/coresight-catu.c
create mode 100644 drivers/hwtracing/coresight/coresight-catu.h

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index ef9cb3c..ad34380 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -31,6 +31,17 @@ config CORESIGHT_LINK_AND_SINK_TMC
complies with the generic implementation of the component without
special enhancement or added features.

+config CORESIGHT_CATU
+ bool "Coresight Address Translation Unit (CATU) driver"
+ depends on CORESIGHT_LINK_AND_SINK_TMC
+ help
+ Enable support for the Coresight Address Translation Unit (CATU).
+ CATU supports a scatter gather table of 4K pages, with forward/backward
+ lookup. CATU helps TMC ETR to use a large physically non-contiguous trace
+ buffer by translating the addresses used by ETR to the physical address
+ by looking up the provided table. CATU can also be used in pass-through
+ mode where the address is not translated.
+
config CORESIGHT_SINK_TPIU
bool "Coresight generic TPIU driver"
depends on CORESIGHT_LINKS_AND_SINKS
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 61db9dd..41870de 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -18,3 +18,4 @@ obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o \
obj-$(CONFIG_CORESIGHT_DYNAMIC_REPLICATOR) += coresight-dynamic-replicator.o
obj-$(CONFIG_CORESIGHT_STM) += coresight-stm.o
obj-$(CONFIG_CORESIGHT_CPU_DEBUG) += coresight-cpu-debug.o
+obj-$(CONFIG_CORESIGHT_CATU) += coresight-catu.o
diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
new file mode 100644
index 0000000..11c84cb
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-catu.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Arm Limited. All rights reserved.
+ *
+ * Coresight Address Translation Unit support
+ *
+ * Author: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
+ */
+
+#include <linux/amba/bus.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "coresight-catu.h"
+#include "coresight-priv.h"
+
+#define csdev_to_catu_drvdata(csdev) \
+ dev_get_drvdata(csdev->dev.parent)
+
+coresight_simple_reg32(struct catu_drvdata, devid, CORESIGHT_DEVID);
+coresight_simple_reg32(struct catu_drvdata, control, CATU_CONTROL);
+coresight_simple_reg32(struct catu_drvdata, status, CATU_STATUS);
+coresight_simple_reg32(struct catu_drvdata, mode, CATU_MODE);
+coresight_simple_reg32(struct catu_drvdata, axictrl, CATU_AXICTRL);
+coresight_simple_reg32(struct catu_drvdata, irqen, CATU_IRQEN);
+coresight_simple_reg64(struct catu_drvdata, sladdr,
+ CATU_SLADDRLO, CATU_SLADDRHI);
+coresight_simple_reg64(struct catu_drvdata, inaddr,
+ CATU_INADDRLO, CATU_INADDRHI);
+
+static struct attribute *catu_mgmt_attrs[] = {
+ &dev_attr_devid.attr,
+ &dev_attr_control.attr,
+ &dev_attr_status.attr,
+ &dev_attr_mode.attr,
+ &dev_attr_axictrl.attr,
+ &dev_attr_irqen.attr,
+ &dev_attr_sladdr.attr,
+ &dev_attr_inaddr.attr,
+ NULL,
+};
+
+static const struct attribute_group catu_mgmt_group = {
+ .attrs = catu_mgmt_attrs,
+ .name = "mgmt",
+};
+
+static const struct attribute_group *catu_groups[] = {
+ &catu_mgmt_group,
+ NULL,
+};
+
+
+static inline int catu_wait_for_ready(struct catu_drvdata *drvdata)
+{
+ return coresight_timeout(drvdata->base,
+ CATU_STATUS, CATU_STATUS_READY, 1);
+}
+
+static int catu_enable_hw(struct catu_drvdata *drvdata, void *__unused)
+{
+ u32 control;
+
+ if (catu_wait_for_ready(drvdata))
+ dev_warn(drvdata->dev, "Timeout while waiting for READY\n");
+
+ control = catu_read_control(drvdata);
+ if (control & BIT(CATU_CONTROL_ENABLE)) {
+ dev_warn(drvdata->dev, "CATU is already enabled\n");
+ return -EBUSY;
+ }
+
+ control |= BIT(CATU_CONTROL_ENABLE);
+ catu_write_mode(drvdata, CATU_MODE_PASS_THROUGH);
+ catu_write_control(drvdata, control);
+ dev_dbg(drvdata->dev, "Enabled in Pass through mode\n");
+ return 0;
+}
+
+static int catu_enable(struct coresight_device *csdev, void *data)
+{
+ int rc;
+ struct catu_drvdata *catu_drvdata = csdev_to_catu_drvdata(csdev);
+
+ CS_UNLOCK(catu_drvdata->base);
+ rc = catu_enable_hw(catu_drvdata, data);
+ CS_LOCK(catu_drvdata->base);
+ return rc;
+}
+
+static int catu_disable_hw(struct catu_drvdata *drvdata)
+{
+ int rc = 0;
+
+ if (catu_wait_for_ready(drvdata)) {
+ dev_info(drvdata->dev, "Timeout while waiting for READY\n");
+ rc = -EAGAIN;
+ }
+
+ catu_write_control(drvdata, 0);
+ dev_dbg(drvdata->dev, "Disabled\n");
+ return rc;
+}
+
+static int catu_disable(struct coresight_device *csdev, void *__unused)
+{
+ int rc;
+ struct catu_drvdata *catu_drvdata = csdev_to_catu_drvdata(csdev);
+
+ CS_UNLOCK(catu_drvdata->base);
+ rc = catu_disable_hw(catu_drvdata);
+ CS_LOCK(catu_drvdata->base);
+ return rc;
+}
+
+const struct coresight_ops_helper catu_helper_ops = {
+ .enable = catu_enable,
+ .disable = catu_disable,
+};
+
+const struct coresight_ops catu_ops = {
+ .helper_ops = &catu_helper_ops,
+};
+
+static int catu_probe(struct amba_device *adev, const struct amba_id *id)
+{
+ int ret = 0;
+ u32 dma_mask;
+ struct catu_drvdata *drvdata;
+ struct coresight_desc catu_desc;
+ struct coresight_platform_data *pdata = NULL;
+ struct device *dev = &adev->dev;
+ struct device_node *np = dev->of_node;
+ void __iomem *base;
+
+ if (np) {
+ pdata = of_get_coresight_platform_data(dev, np);
+ if (IS_ERR(pdata)) {
+ ret = PTR_ERR(pdata);
+ goto out;
+ }
+ dev->platform_data = pdata;
+ }
+
+ drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+ if (!drvdata) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ drvdata->dev = dev;
+ dev_set_drvdata(dev, drvdata);
+ base = devm_ioremap_resource(dev, &adev->res);
+ if (IS_ERR(base)) {
+ ret = PTR_ERR(base);
+ goto out;
+ }
+
+ /* Setup dma mask for the device */
+ dma_mask = readl_relaxed(base + CORESIGHT_DEVID) & 0x3f;
+ switch (dma_mask) {
+ case 32:
+ case 40:
+ case 44:
+ case 48:
+ case 52:
+ case 56:
+ case 64:
+ break;
+ default:
+ /* Default to the 40bits as supported by TMC-ETR */
+ dma_mask = 40;
+ }
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(dma_mask));
+ if (ret)
+ goto out;
+
+ drvdata->base = base;
+ catu_desc.pdata = pdata;
+ catu_desc.dev = dev;
+ catu_desc.groups = catu_groups;
+ catu_desc.type = CORESIGHT_DEV_TYPE_HELPER;
+ catu_desc.subtype.helper_subtype = CORESIGHT_DEV_SUBTYPE_HELPER_CATU;
+ catu_desc.ops = &catu_ops;
+ drvdata->csdev = coresight_register(&catu_desc);
+ if (IS_ERR(drvdata->csdev))
+ ret = PTR_ERR(drvdata->csdev);
+out:
+ pm_runtime_put(&adev->dev);
+ return ret;
+}
+
+static struct amba_id catu_ids[] = {
+ {
+ .id = 0x000bb9ee,
+ .mask = 0x000fffff,
+ },
+ {},
+};
+
+static struct amba_driver catu_driver = {
+ .drv = {
+ .name = "coresight-catu",
+ .owner = THIS_MODULE,
+ .suppress_bind_attrs = true,
+ },
+ .probe = catu_probe,
+ .id_table = catu_ids,
+};
+
+builtin_amba_driver(catu_driver);
diff --git a/drivers/hwtracing/coresight/coresight-catu.h b/drivers/hwtracing/coresight/coresight-catu.h
new file mode 100644
index 0000000..05da33d
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-catu.h
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 Arm Limited. All rights reserved.
+ *
+ * Author: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
+ */
+
+#ifndef _CORESIGHT_CATU_H
+#define _CORESIGHT_CATU_H
+
+#include "coresight-priv.h"
+
+/* Register offset from base */
+#define CATU_CONTROL 0x000
+#define CATU_MODE 0x004
+#define CATU_AXICTRL 0x008
+#define CATU_IRQEN 0x00c
+#define CATU_SLADDRLO 0x020
+#define CATU_SLADDRHI 0x024
+#define CATU_INADDRLO 0x028
+#define CATU_INADDRHI 0x02c
+#define CATU_STATUS 0x100
+#define CATU_DEVARCH 0xfbc
+
+#define CATU_CONTROL_ENABLE 0
+
+#define CATU_MODE_PASS_THROUGH 0U
+#define CATU_MODE_TRANSLATE 1U
+
+#define CATU_STATUS_READY 8
+#define CATU_STATUS_ADRERR 0
+#define CATU_STATUS_AXIERR 4
+
+#define CATU_IRQEN_ON 0x1
+#define CATU_IRQEN_OFF 0x0
+
+struct catu_drvdata {
+ struct device *dev;
+ void __iomem *base;
+ struct coresight_device *csdev;
+ int irq;
+};
+
+#define CATU_REG32(name, offset) \
+static inline u32 \
+catu_read_##name(struct catu_drvdata *drvdata) \
+{ \
+ return coresight_read_reg_pair(drvdata->base, offset, -1); \
+} \
+static inline void \
+catu_write_##name(struct catu_drvdata *drvdata, u32 val) \
+{ \
+ coresight_write_reg_pair(drvdata->base, val, offset, -1); \
+}
+
+#define CATU_REG_PAIR(name, lo_off, hi_off) \
+static inline u64 \
+catu_read_##name(struct catu_drvdata *drvdata) \
+{ \
+ return coresight_read_reg_pair(drvdata->base, lo_off, hi_off); \
+} \
+static inline void \
+catu_write_##name(struct catu_drvdata *drvdata, u64 val) \
+{ \
+ coresight_write_reg_pair(drvdata->base, val, lo_off, hi_off); \
+}
+
+CATU_REG32(control, CATU_CONTROL);
+CATU_REG32(mode, CATU_MODE);
+CATU_REG_PAIR(sladdr, CATU_SLADDRLO, CATU_SLADDRHI)
+CATU_REG_PAIR(inaddr, CATU_INADDRLO, CATU_INADDRHI)
+
+static inline bool coresight_is_catu_device(struct coresight_device *csdev)
+{
+ enum coresight_dev_subtype_helper subtype;
+
+ /* Make the checkpatch happy */
+ subtype = csdev->subtype.helper_subtype;
+
+ return IS_ENABLED(CONFIG_CORESIGHT_CATU) &&
+ csdev->type == CORESIGHT_DEV_TYPE_HELPER &&
+ subtype == CORESIGHT_DEV_SUBTYPE_HELPER_CATU;
+}
+
+#endif
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 8af4512..e37923a 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -9,6 +9,7 @@
#include <linux/iommu.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
+#include "coresight-catu.h"
#include "coresight-priv.h"
#include "coresight-tmc.h"

@@ -701,6 +702,48 @@ static const struct etr_buf_operations etr_sg_buf_ops = {
.get_data = tmc_etr_get_data_sg_buf,
};

+/*
+ * TMC ETR could be connected to a CATU device, which can provide address
+ * translation service. This is represented by the Output port of the TMC
+ * (ETR) connected to the input port of the CATU.
+ *
+ * Returns : coresight_device ptr for the CATU device if a CATU is found.
+ * : NULL otherwise.
+ */
+static inline struct coresight_device *
+tmc_etr_get_catu_device(struct tmc_drvdata *drvdata)
+{
+ int i;
+ struct coresight_device *tmp, *etr = drvdata->csdev;
+
+ if (!IS_ENABLED(CONFIG_CORESIGHT_CATU))
+ return NULL;
+
+ for (i = 0; i < etr->nr_outport; i++) {
+ tmp = etr->conns[i].child_dev;
+ if (tmp && coresight_is_catu_device(tmp))
+ return tmp;
+ }
+
+ return NULL;
+}
+
+static inline void tmc_etr_enable_catu(struct tmc_drvdata *drvdata)
+{
+ struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
+
+ if (catu && helper_ops(catu)->enable)
+ helper_ops(catu)->enable(catu, NULL);
+}
+
+static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata)
+{
+ struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
+
+ if (catu && helper_ops(catu)->disable)
+ helper_ops(catu)->disable(catu, NULL);
+}
+
static const struct etr_buf_operations *etr_buf_ops[] = {
[ETR_MODE_FLAT] = &etr_flat_buf_ops,
[ETR_MODE_ETR_SG] = &etr_sg_buf_ops,
@@ -844,6 +887,12 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
u32 axictl, sts;
struct etr_buf *etr_buf = drvdata->etr_buf;

+ /*
+ * If this ETR is connected to a CATU, enable it before we turn
+ * this on
+ */
+ tmc_etr_enable_catu(drvdata);
+
CS_UNLOCK(drvdata->base);

/* Wait for TMCSReady bit to be set */
@@ -952,6 +1001,9 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
tmc_disable_hw(drvdata);

CS_LOCK(drvdata->base);
+
+ /* Disable CATU device if this ETR is connected to one */
+ tmc_etr_disable_catu(drvdata);
}

static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 3d40a2b..d828a6e 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -65,6 +65,7 @@ enum coresight_dev_subtype_source {

enum coresight_dev_subtype_helper {
CORESIGHT_DEV_SUBTYPE_HELPER_NONE,
+ CORESIGHT_DEV_SUBTYPE_HELPER_CATU,
};

/**
--
2.7.4