Hello.

On 03/31/2015 01:51 AM, Sergei Shtylyov wrote:

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Ethernet AVB includes an Gigabit Ethernet controller (E-MAC) that is basically
compatible with SuperH Gigabit Ethernet E-MAC). Ethernet AVB  has a dedicated
direct memory access controller (AVB-DMAC) that is a new design compared to
the
SuperH E-DMAC. The AVB-DMAC is compliant with 3 standards formulated for IEEE
802.1BA: IEEE 802.1AS timing and synchronization protocol, IEEE 802.1Qav real-
time transfer, and the IEEE 802.1Qat stream reservation protocol.

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The driver only supports device tree probing, so the binding document is
included in this patch.

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Based on the patches by Mitsuhiro Kimura [off-list ref] and
Masaru Nagai [off-list ref].

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Signed-off-by: Sergei Shtylyov <redacted>

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Index: net-next/drivers/net/ethernet/renesas/ravb.c
===================================================================

--- /dev/null
+++ net-next/drivers/net/ethernet/renesas/ravb.c

@@ -0,0 +1,3071 @@

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+/* There is CPU dependent code */
+static int ravb_wait_clear(struct net_device *ndev, u16 reg, u32 bits)
+{
+    int i;
+
+    for (i = 0; i < 100; i++) {
+        if (!(ravb_read(ndev, reg) & bits))
+            break;
+        mdelay(1);
+    }
+    if (i >= 100)
+        return -ETIMEDOUT;
+
+    return 0;
+}
+
+static int ravb_wait_setting(struct net_device *ndev, u16 reg, u32 bits)
+{

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This function is identical to the previous one.

    It is not, the *break* condition is different. I'll look into merging them
though...

    Done.

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+/* Caller must hold the lock */
+static void ravb_ptp_update_compare(struct ravb_private *priv, u32 ns)
+{
+    struct net_device *ndev = priv->ndev;
+    /* When the comparison value (GPTC.PTCV) is in range of
+     * [x-1 to x+1] (x is the configured increment value in
+     * GTI.TIV), it may happen that a comparison match is
+     * not detected when the timer wraps around.
+     */

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What does this funtion do, exactly?

    Loads the new timer comparator value, apparenlty.

 This looks very fishy to me.

    Perhaps a workaround for an errata I don't know about.

    Or perhaps it's to keep the comparison value between x and 2**32 - x 
(where x is increment in ns) as required by the manual?

Nagai-san, could you maybe elaborate?

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+static bool ravb_ptp_is_config(struct ravb_private *priv)
+{

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This is a bit hacky.  Can't your driver make sure that the HW is ready?

    Will look into this. Perhaps it's a remainder from when the PTP driver was
separate...

    No, we enter this mode upon closing the Ethernet device and when the ring 
DMA sizes are changed. Seems unavoidable...

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+    if (ravb_read(priv->ndev, CSR) & CSR_OPS_CONFIG)
+        return true;
+    else
+        return false;
+}
+

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WBR, Sergei