stmmac: add HW DMA feature register (v3)

New GMAC chips have an extra register to indicate
the presence of the optional features/functions of
the DMA core.

This patch adds this support and all the HW cap
are exported via debugfs.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index eb210ca..d0fbc54 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -780,6 +780,49 @@
 	}
 	return 0;
 }
+
+/* New GMAC chips support a new register to indicate the
+ * presence of the optional feature/functions.
+ */
+static int stmmac_get_hw_features(struct stmmac_priv *priv)
+{
+	u32 hw_cap = priv->hw->dma->get_hw_feature(priv->ioaddr);
+
+	if (likely(hw_cap)) {
+		priv->dma_cap.mbps_10_100 = (hw_cap & 0x1);
+		priv->dma_cap.mbps_1000 = (hw_cap & 0x2) >> 1;
+		priv->dma_cap.half_duplex = (hw_cap & 0x4) >> 2;
+		priv->dma_cap.hash_filter = (hw_cap & 0x10) >> 4;
+		priv->dma_cap.multi_addr = (hw_cap & 0x20) >> 5;
+		priv->dma_cap.pcs = (hw_cap & 0x40) >> 6;
+		priv->dma_cap.sma_mdio = (hw_cap & 0x100) >> 8;
+		priv->dma_cap.pmt_remote_wake_up = (hw_cap & 0x200) >> 9;
+		priv->dma_cap.pmt_magic_frame = (hw_cap & 0x400) >> 10;
+		priv->dma_cap.rmon = (hw_cap & 0x800) >> 11; /* MMC */
+		/* IEEE 1588-2002*/
+		priv->dma_cap.time_stamp = (hw_cap & 0x1000) >> 12;
+		/* IEEE 1588-2008*/
+		priv->dma_cap.atime_stamp = (hw_cap & 0x2000) >> 13;
+		/* 802.3az - Energy-Efficient Ethernet (EEE) */
+		priv->dma_cap.eee = (hw_cap & 0x4000) >> 14;
+		priv->dma_cap.av = (hw_cap & 0x8000) >> 15;
+		/* TX and RX csum */
+		priv->dma_cap.tx_coe = (hw_cap & 0x10000) >> 16;
+		priv->dma_cap.rx_coe_type1 = (hw_cap & 0x20000) >> 17;
+		priv->dma_cap.rx_coe_type2 = (hw_cap & 0x40000) >> 18;
+		priv->dma_cap.rxfifo_over_2048 = (hw_cap & 0x80000) >> 19;
+		/* TX and RX number of channels */
+		priv->dma_cap.number_rx_channel = (hw_cap & 0x300000) >> 20;
+		priv->dma_cap.number_tx_channel = (hw_cap & 0xc00000) >> 22;
+		/* Alternate (enhanced) DESC mode*/
+		priv->dma_cap.enh_desc = (hw_cap & 0x1000000) >> 24;
+
+	} else
+		pr_debug("\tNo HW DMA feature register supported");
+
+	return hw_cap;
+}
+
 /**
  *  stmmac_open - open entry point of the driver
  *  @dev : pointer to the device structure.
@@ -854,6 +897,8 @@
 
 	stmmac_get_synopsys_id(priv);
 
+	stmmac_get_hw_features(priv);
+
 	if (priv->rx_coe)
 		pr_info("stmmac: Rx Checksum Offload Engine supported\n");
 	if (priv->plat->tx_coe)
@@ -1450,6 +1495,7 @@
 #ifdef CONFIG_STMMAC_DEBUG_FS
 static struct dentry *stmmac_fs_dir;
 static struct dentry *stmmac_rings_status;
+static struct dentry *stmmac_dma_cap;
 
 static int stmmac_sysfs_ring_read(struct seq_file *seq, void *v)
 {
@@ -1503,6 +1549,78 @@
 	.release = seq_release,
 };
 
+static int stmmac_sysfs_dma_cap_read(struct seq_file *seq, void *v)
+{
+	struct net_device *dev = seq->private;
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	if (!stmmac_get_hw_features(priv)) {
+		seq_printf(seq, "DMA HW features not supported\n");
+		return 0;
+	}
+
+	seq_printf(seq, "==============================\n");
+	seq_printf(seq, "\tDMA HW features\n");
+	seq_printf(seq, "==============================\n");
+
+	seq_printf(seq, "\t10/100 Mbps %s\n",
+		   (priv->dma_cap.mbps_10_100) ? "Y" : "N");
+	seq_printf(seq, "\t1000 Mbps %s\n",
+		   (priv->dma_cap.mbps_1000) ? "Y" : "N");
+	seq_printf(seq, "\tHalf duple %s\n",
+		   (priv->dma_cap.half_duplex) ? "Y" : "N");
+	seq_printf(seq, "\tHash Filter: %s\n",
+		   (priv->dma_cap.hash_filter) ? "Y" : "N");
+	seq_printf(seq, "\tMultiple MAC address registers: %s\n",
+		   (priv->dma_cap.multi_addr) ? "Y" : "N");
+	seq_printf(seq, "\tPCS (TBI/SGMII/RTBI PHY interfatces): %s\n",
+		   (priv->dma_cap.pcs) ? "Y" : "N");
+	seq_printf(seq, "\tSMA (MDIO) Interface: %s\n",
+		   (priv->dma_cap.sma_mdio) ? "Y" : "N");
+	seq_printf(seq, "\tPMT Remote wake up: %s\n",
+		   (priv->dma_cap.pmt_remote_wake_up) ? "Y" : "N");
+	seq_printf(seq, "\tPMT Magic Frame: %s\n",
+		   (priv->dma_cap.pmt_magic_frame) ? "Y" : "N");
+	seq_printf(seq, "\tRMON module: %s\n",
+		   (priv->dma_cap.rmon) ? "Y" : "N");
+	seq_printf(seq, "\tIEEE 1588-2002 Time Stamp: %s\n",
+		   (priv->dma_cap.time_stamp) ? "Y" : "N");
+	seq_printf(seq, "\tIEEE 1588-2008 Advanced Time Stamp:%s\n",
+		   (priv->dma_cap.atime_stamp) ? "Y" : "N");
+	seq_printf(seq, "\t802.3az - Energy-Efficient Ethernet (EEE) %s\n",
+		   (priv->dma_cap.eee) ? "Y" : "N");
+	seq_printf(seq, "\tAV features: %s\n", (priv->dma_cap.av) ? "Y" : "N");
+	seq_printf(seq, "\tChecksum Offload in TX: %s\n",
+		   (priv->dma_cap.tx_coe) ? "Y" : "N");
+	seq_printf(seq, "\tIP Checksum Offload (type1) in RX: %s\n",
+		   (priv->dma_cap.rx_coe_type1) ? "Y" : "N");
+	seq_printf(seq, "\tIP Checksum Offload (type2) in RX: %s\n",
+		   (priv->dma_cap.rx_coe_type2) ? "Y" : "N");
+	seq_printf(seq, "\tRXFIFO > 2048bytes: %s\n",
+		   (priv->dma_cap.rxfifo_over_2048) ? "Y" : "N");
+	seq_printf(seq, "\tNumber of Additional RX channel: %d\n",
+		   priv->dma_cap.number_rx_channel);
+	seq_printf(seq, "\tNumber of Additional TX channel: %d\n",
+		   priv->dma_cap.number_tx_channel);
+	seq_printf(seq, "\tEnhanced descriptors: %s\n",
+		   (priv->dma_cap.enh_desc) ? "Y" : "N");
+
+	return 0;
+}
+
+static int stmmac_sysfs_dma_cap_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, stmmac_sysfs_dma_cap_read, inode->i_private);
+}
+
+static const struct file_operations stmmac_dma_cap_fops = {
+	.owner = THIS_MODULE,
+	.open = stmmac_sysfs_dma_cap_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = seq_release,
+};
+
 static int stmmac_init_fs(struct net_device *dev)
 {
 	/* Create debugfs entries */
@@ -1527,12 +1645,25 @@
 		return -ENOMEM;
 	}
 
+	/* Entry to report the DMA HW features */
+	stmmac_dma_cap = debugfs_create_file("dma_cap", S_IRUGO, stmmac_fs_dir,
+					     dev, &stmmac_dma_cap_fops);
+
+	if (!stmmac_dma_cap || IS_ERR(stmmac_dma_cap)) {
+		pr_info("ERROR creating stmmac MMC debugfs file\n");
+		debugfs_remove(stmmac_rings_status);
+		debugfs_remove(stmmac_fs_dir);
+
+		return -ENOMEM;
+	}
+
 	return 0;
 }
 
 static void stmmac_exit_fs(void)
 {
 	debugfs_remove(stmmac_rings_status);
+	debugfs_remove(stmmac_dma_cap);
 	debugfs_remove(stmmac_fs_dir);
 }
 #endif /* CONFIG_STMMAC_DEBUG_FS */