Add support for devices with system instruction access only.
They don't have a memory mapped interface and thus are not
AMBA devices.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <redacted>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 drivers/hwtracing/coresight/coresight-etm4x.c | 42 ++++++++++++++++++-
 1 file changed, 40 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 7d5f942c2108..212713ffa37e 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c

@@ -26,6 +26,7 @@
 #include <linux/seq_file.h>
 #include <linux/uaccess.h>
 #include <linux/perf_event.h>
+#include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/property.h>
 #include <asm/sections.h>

@@ -1712,6 +1713,20 @@ static int etm4_probe_amba(struct amba_device *adev, const struct amba_id *id)
        return ret;
 }

+static int etm4_probe_platform_dev(struct platform_device *pdev)
+{
+       int ret;
+
+       pm_runtime_get_noresume(&pdev->dev);
+       pm_runtime_set_active(&pdev->dev);
+       pm_runtime_enable(&pdev->dev);
+

+       ret = etm4_probe(&pdev->dev, NULL);
+
+       pm_runtime_put(&pdev->dev);
+       return ret;
+}
+
 static struct amba_cs_uci_id uci_id_etm4[] = {
        {
                /*  ETMv4 UCI data */

@@ -1749,6 +1764,20 @@ static struct amba_driver etm4x_amba_driver = {
        .id_table       = etm4_ids,
 };

+static const struct of_device_id etm4_4_match[] = {
+       { .compatible   = "arm,coresight-etm-v4.4" },
+       {}
+};
+
+static struct platform_driver etm4_platform_driver = {
+       .probe          = etm4_probe_platform_dev,
+       .driver                 = {
+               .name                   = "coresight-etm4x",
+               .of_match_table         = etm4_4_match,
+               .suppress_bind_attrs    = true,
+       },
+};
+
 static int __init etm4x_init(void)
 {
        int ret;

@@ -1761,10 +1790,19 @@ static int __init etm4x_init(void)

        ret = amba_driver_register(&etm4x_amba_driver);
        if (ret) {
-               pr_err("Error registering etm4x driver\n");
-               etm4_pm_clear();
+               pr_err("Error registering etm4x AMBA driver\n");
+               goto clear_pm;
        }

+       ret = platform_driver_register(&etm4_platform_driver);
+       if (!ret)
+               return 0;
+
+       pr_err("Error registering etm4x platform driver\n");
+       amba_driver_unregister(&etm4x_amba_driver);
+
+clear_pm:
+       etm4_pm_clear();
        return ret;
 }
 device_initcall(etm4x_init);
--

2.24.1