coresight-tpda: Add DSB dataset support

Read the DSB element size from the device tree. Set the register
bit that controls the DSB element size of the corresponding port.

Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1695882586-10306-5-git-send-email-quic_taozha@quicinc.com

diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/hwtracing/coresight/coresight-tpda.c
index 8d2b9d29237d47323515c54dc017dc0e20ca8d85..5f82737c37bba5b063c8a80c86e78227b7759cc9 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-tpda.c
+++ b/drivers/hwtracing/coresight/coresight-tpda.c
@@ -21,6 +21,80 @@
 
 DEFINE_CORESIGHT_DEVLIST(tpda_devs, "tpda");
 
+static bool coresight_device_is_tpdm(struct coresight_device *csdev)
+{
+       return (csdev->type == CORESIGHT_DEV_TYPE_SOURCE) &&
+              (csdev->subtype.source_subtype ==
+                       CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM);
+}
+
+/*
+ * Read the DSB element size from the TPDM device
+ * Returns
+ *    The dsb element size read from the devicetree if available.
+ *    0 - Otherwise, with a warning once.
+ */
+static int tpdm_read_dsb_element_size(struct coresight_device *csdev)
+{
+       int rc = 0;
+       u8 size = 0;
+
+       rc = fwnode_property_read_u8(dev_fwnode(csdev->dev.parent),
+                       "qcom,dsb-element-size", &size);
+       if (rc)
+               dev_warn_once(&csdev->dev,
+                       "Failed to read TPDM DSB Element size: %d\n", rc);
+
+       return size;
+}
+
+/*
+ * Search and read element data size from the TPDM node in
+ * the devicetree. Each input port of TPDA is connected to
+ * a TPDM. Different TPDM supports different types of dataset,
+ * and some may support more than one type of dataset.
+ * Parameter "inport" is used to pass in the input port number
+ * of TPDA, and it is set to -1 in the recursize call.
+ */
+static int tpda_get_element_size(struct coresight_device *csdev,
+                                int inport)
+{
+       int dsb_size = -ENOENT;
+       int i, size;
+       struct coresight_device *in;
+
+       for (i = 0; i < csdev->pdata->nr_inconns; i++) {
+               in = csdev->pdata->in_conns[i]->src_dev;
+               if (!in)
+                       continue;
+
+               /* Ignore the paths that do not match port */
+               if (inport > 0 &&
+                   csdev->pdata->in_conns[i]->dest_port != inport)
+                       continue;
+
+               if (coresight_device_is_tpdm(in)) {
+                       size = tpdm_read_dsb_element_size(in);
+               } else {
+                       /* Recurse down the path */
+                       size = tpda_get_element_size(in, -1);
+               }
+
+               if (size < 0)
+                       return size;
+
+               if (dsb_size < 0) {
+                       /* Found a size, save it. */
+                       dsb_size = size;
+               } else {
+                       /* Found duplicate TPDMs */
+                       return -EEXIST;
+               }
+       }
+
+       return dsb_size;
+}
+
 /* Settings pre enabling port control register */
 static void tpda_enable_pre_port(struct tpda_drvdata *drvdata)
 {
@@ -32,26 +106,55 @@ static void tpda_enable_pre_port(struct tpda_drvdata *drvdata)
        writel_relaxed(val, drvdata->base + TPDA_CR);
 }
 
-static void tpda_enable_port(struct tpda_drvdata *drvdata, int port)
+static int tpda_enable_port(struct tpda_drvdata *drvdata, int port)
 {
        u32 val;
+       int size;
 
        val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port));
+       /*
+        * Configure aggregator port n DSB data set element size
+        * Set the bit to 0 if the size is 32
+        * Set the bit to 1 if the size is 64
+        */
+       size = tpda_get_element_size(drvdata->csdev, port);
+       switch (size) {
+       case 32:
+               val &= ~TPDA_Pn_CR_DSBSIZE;
+               break;
+       case 64:
+               val |= TPDA_Pn_CR_DSBSIZE;
+               break;
+       case 0:
+               return -EEXIST;
+       case -EEXIST:
+               dev_warn_once(&drvdata->csdev->dev,
+                       "Detected multiple TPDMs on port %d", -EEXIST);
+               return -EEXIST;
+       default:
+               return -EINVAL;
+       }
+
        /* Enable the port */
        val |= TPDA_Pn_CR_ENA;
        writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
+
+       return 0;
 }
 
-static void __tpda_enable(struct tpda_drvdata *drvdata, int port)
+static int __tpda_enable(struct tpda_drvdata *drvdata, int port)
 {
+       int ret;
+
        CS_UNLOCK(drvdata->base);
 
        if (!drvdata->csdev->enable)
                tpda_enable_pre_port(drvdata);
 
-       tpda_enable_port(drvdata, port);
-
+       ret = tpda_enable_port(drvdata, port);
        CS_LOCK(drvdata->base);
+
+       return ret;
 }
 
 static int tpda_enable(struct coresight_device *csdev,
@@ -59,16 +162,19 @@ static int tpda_enable(struct coresight_device *csdev,
                       struct coresight_connection *out)
 {
        struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+       int ret = 0;
 
        spin_lock(&drvdata->spinlock);
-       if (atomic_read(&in->dest_refcnt) == 0)
-               __tpda_enable(drvdata, in->dest_port);
+       if (atomic_read(&in->dest_refcnt) == 0) {
+               ret = __tpda_enable(drvdata, in->dest_port);
+               if (!ret) {
+                       atomic_inc(&in->dest_refcnt);
+                       dev_dbg(drvdata->dev, "TPDA inport %d enabled.\n", in->dest_port);
+               }
+       }
 
-       atomic_inc(&in->dest_refcnt);
        spin_unlock(&drvdata->spinlock);
-
-       dev_dbg(drvdata->dev, "TPDA inport %d enabled.\n", in->dest_port);
-       return 0;
+       return ret;
 }
 
 static void __tpda_disable(struct tpda_drvdata *drvdata, int port)

diff --git a/drivers/hwtracing/coresight/coresight-tpda.h b/drivers/hwtracing/coresight/coresight-tpda.h
index 0399678df312fb3674df3d101e059e6b850d538b..b3b38fd41b64bc84ceacff3926fe34341f8f1a25 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-tpda.h
+++ b/drivers/hwtracing/coresight/coresight-tpda.h
@@ -10,6 +10,8 @@
 #define TPDA_Pn_CR(n)          (0x004 + (n * 4))
 /* Aggregator port enable bit */
 #define TPDA_Pn_CR_ENA         BIT(0)
+/* Aggregator port DSB data set element size bit */
+#define TPDA_Pn_CR_DSBSIZE             BIT(8)
 
 #define TPDA_MAX_INPORTS       32