On 19/12/2023 02:13, Tao Zhang wrote:

On 12/18/2023 6:27 PM, Suzuki K Poulose wrote:

quoted

On 21/11/2023 02:24, Tao Zhang wrote:

quoted

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

Signed-off-by: Tao Zhang <redacted>
Signed-off-by: Mao Jinlong <redacted>
---
  drivers/hwtracing/coresight/coresight-tpda.c | 117 +++++++++++--------
  drivers/hwtracing/coresight/coresight-tpda.h |   6 +
  2 files changed, 74 insertions(+), 49 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tpda.c 

b/drivers/hwtracing/coresight/coresight-tpda.c
index 5f82737c37bb..e3762f38abb3 100644

--- a/drivers/hwtracing/coresight/coresight-tpda.c
+++ b/drivers/hwtracing/coresight/coresight-tpda.c

@@ -28,24 +28,54 @@ static bool coresight_device_is_tpdm(struct 

coresight_device *csdev)
              CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM);
  }
  +static void tpdm_clear_element_size(struct coresight_device *csdev)
+{
+    struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+    if (drvdata->dsb_esize)
+        drvdata->dsb_esize = 0;
+    if (drvdata->cmb_esize)
+        drvdata->cmb_esize = 0;

Why do we need the if (...) check here ?

The element size of all the TPDM sub-unit should be set to 0 here.

I will update this in the next patch series.

quoted

quoted

+}
+
+static void tpda_set_element_size(struct tpda_drvdata *drvdata, u32 
*val)
+{
+
+    if (drvdata->dsb_esize == 64)
+        *val |= TPDA_Pn_CR_DSBSIZE;
+    else if (drvdata->dsb_esize == 32)
+        *val &= ~TPDA_Pn_CR_DSBSIZE;
+
+    if (drvdata->cmb_esize == 64)
+        *val |= FIELD_PREP(TPDA_Pn_CR_CMBSIZE, 0x2);
+    else if (drvdata->cmb_esize == 32)
+        *val |= FIELD_PREP(TPDA_Pn_CR_CMBSIZE, 0x1);
+    else if (drvdata->cmb_esize == 8)
+        *val &= ~TPDA_Pn_CR_CMBSIZE;
+}
+

quoted

  /*
- * Read the DSB element size from the TPDM device
+ * Read the element size from the TPDM device
   * Returns
- *    The dsb element size read from the devicetree if available.
+ *    The element size read from the devicetree if available.
   *    0 - Otherwise, with a warning once.

This doesn't match the function ? It return 0 on success and
error (-EINVAL) on failure ?

0 means the element size property is found from the devicetree.

Otherwise, it will return error(-EINVAL).

I will update this in the next patch series.

quoted

quoted

   */
-static int tpdm_read_dsb_element_size(struct coresight_device *csdev)
+static int tpdm_read_element_size(struct tpda_drvdata *drvdata,
+                  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);
+    int rc = -EINVAL;
+
+    if (!fwnode_property_read_u8(dev_fwnode(csdev->dev.parent),
+            "qcom,dsb-element-size", &drvdata->dsb_esize))
+        rc = 0;
+    if (!fwnode_property_read_u8(dev_fwnode(csdev->dev.parent),
+            "qcom,cmb-element-size", &drvdata->cmb_esize))
+        rc = 0;

Are we not silently resetting the error if the former failed ?

Could we not :

    rc |= fwnode_...

    rc |= fwnode_...

instead ?

Also what is the expectation here ? Are these properties a MUST for
TPDM ?

The TPDM must have one of the element size property. As long as one

Please add a comment in the function. Someone else might try to "fix"
it otherwise.

Suzuki

can be found, this TPDM configuration can be considered valid. So this

function will return 0 if one of the element size property is found.

Best,

Tao

quoted

quoted

      if (rc)
          dev_warn_once(&csdev->dev,
-            "Failed to read TPDM DSB Element size: %d\n", rc);
+            "Failed to read TPDM Element size: %d\n", rc);
  -    return size;
+    return rc;
  }
    /*

@@ -56,11 +86,12 @@ static int tpdm_read_dsb_element_size(struct 

coresight_device *csdev)
   * 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,
+static int tpda_get_element_size(struct tpda_drvdata *drvdata,
+                 struct coresight_device *csdev,
                   int inport)
  {
-    int dsb_size = -ENOENT;
-    int i, size;
+    int rc = 0;
+    int i;
      struct coresight_device *in;
        for (i = 0; i < csdev->pdata->nr_inconns; i++) {

@@ -74,25 +105,21 @@ static int tpda_get_element_size(struct 

coresight_device *csdev,
              continue;
            if (coresight_device_is_tpdm(in)) {
-            size = tpdm_read_dsb_element_size(in);
+            if ((drvdata->dsb_esize) || (drvdata->cmb_esize))
+                return -EEXIST;
+            rc = tpdm_read_element_size(drvdata, in);
+            if (rc)
+                return rc;
          } 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;
+            rc = tpda_get_element_size(drvdata, in, -1);
+            if (rc)
+                return rc;
          }
      }
  -    return dsb_size;
+
+    return rc;
  }
    /* Settings pre enabling port control register */

@@ -109,7 +136,7 @@ static void tpda_enable_pre_port(struct 

tpda_drvdata *drvdata)
  static int tpda_enable_port(struct tpda_drvdata *drvdata, int port)
  {
      u32 val;
-    int size;
+    int rc;
        val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port));
      /*

@@ -117,29 +144,21 @@ static int tpda_enable_port(struct tpda_drvdata 

*drvdata, int port)
       * 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:
+    tpdm_clear_element_size(drvdata->csdev);
+    rc = tpda_get_element_size(drvdata, drvdata->csdev, port);
+    if (!rc && ((drvdata->dsb_esize) || (drvdata->cmb_esize))) {
+        tpda_set_element_size(drvdata, &val);
+        /* Enable the port */
+        val |= TPDA_Pn_CR_ENA;
+        writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
+    } else if (rc == -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));
+                  "Detected multiple TPDMs on port %d", -EEXIST);
+    else
+        dev_warn_once(&drvdata->csdev->dev,
+                  "Didn't find TPDM elem size");

"element size"

quoted

  -    return 0;
+    return rc;
  }
    static int __tpda_enable(struct tpda_drvdata *drvdata, int port)

diff --git a/drivers/hwtracing/coresight/coresight-tpda.h 

b/drivers/hwtracing/coresight/coresight-tpda.h
index b3b38fd41b64..29164fd9711f 100644

--- 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 CMB data set element size bit */
+#define TPDA_Pn_CR_CMBSIZE        GENMASK(7, 6)
  /* Aggregator port DSB data set element size bit */
  #define TPDA_Pn_CR_DSBSIZE        BIT(8)
  @@ -25,6 +27,8 @@
   * @csdev:      component vitals needed by the framework.
   * @spinlock:   lock for the drvdata value.
   * @enable:     enable status of the component.
+ * @dsb_esize   Record the DSB element size.
+ * @cmb_esize   Record the CMB element size.
   */
  struct tpda_drvdata {
      void __iomem        *base;

@@ -32,6 +36,8 @@ struct tpda_drvdata {

      struct coresight_device    *csdev;
      spinlock_t        spinlock;
      u8            atid;
+    u8            dsb_esize;
+    u8            cmb_esize;
  };
    #endif  /* _CORESIGHT_CORESIGHT_TPDA_H */

Suzuki

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