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From: Herve Codina <herve.codina@bootlin.com>
To: "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>,
	Paolo Abeni <pabeni@redhat.com>,
	Herve Codina <herve.codina@bootlin.com>
Cc: linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org,
	linuxppc-dev@lists.ozlabs.org,
	Andrew Lunn <andrew@lunn.ch>,
	Mark Brown <broonie@kernel.org>,
	Christophe Leroy <christophe.leroy@csgroup.eu>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Subject: [PATCH 3/4] net: wan: fsl_qmc_hdlc: Add runtime timeslots changes support
Date: Tue, 23 Jan 2024 17:49:08 +0100
Message-ID: <20240123164912.249540-4-herve.codina@bootlin.com>
In-Reply-To: <20240123164912.249540-1-herve.codina@bootlin.com>
References: <20240123164912.249540-1-herve.codina@bootlin.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

QMC channels support runtime timeslots changes but nothing is done at
the QMC HDLC driver to handle these changes.

Use existing IFACE ioctl in order to configure the timeslots to use.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/wan/fsl_qmc_hdlc.c | 169 ++++++++++++++++++++++++++++++++-
 1 file changed, 168 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wan/fsl_qmc_hdlc.c b/drivers/net/wan/fsl_qmc_hdlc.c
index 31b637ec8390..82019cd96365 100644
--- a/drivers/net/wan/fsl_qmc_hdlc.c
+++ b/drivers/net/wan/fsl_qmc_hdlc.c
@@ -32,6 +32,7 @@ struct qmc_hdlc {
 	struct qmc_hdlc_desc tx_descs[8];
 	unsigned int tx_out;
 	struct qmc_hdlc_desc rx_descs[4];
+	u32 slot_map;
 };
 
 static inline struct qmc_hdlc *netdev_to_qmc_hdlc(struct net_device *netdev)
@@ -202,6 +203,162 @@ static netdev_tx_t qmc_hdlc_xmit(struct sk_buff *skb, struct net_device *netdev)
 	return NETDEV_TX_OK;
 }
 
+static int qmc_hdlc_xlate_slot_map(struct qmc_hdlc *qmc_hdlc,
+				   u32 slot_map, struct qmc_chan_ts_info *ts_info)
+{
+	u64 ts_mask_avail;
+	unsigned int bit;
+	unsigned int i;
+	u64 ts_mask;
+	u64 map;
+
+	/* Tx and Rx masks must be identical */
+	if (ts_info->rx_ts_mask_avail != ts_info->tx_ts_mask_avail) {
+		dev_err(qmc_hdlc->dev, "tx and rx available timeslots mismatch (0x%llx, 0x%llx)\n",
+			ts_info->rx_ts_mask_avail, ts_info->tx_ts_mask_avail);
+		return -EINVAL;
+	}
+
+	ts_mask_avail = ts_info->rx_ts_mask_avail;
+	ts_mask = 0;
+	map = slot_map;
+	bit = 0;
+	for (i = 0; i < 64; i++) {
+		if (ts_mask_avail & BIT_ULL(i)) {
+			if (map & BIT_ULL(bit))
+				ts_mask |= BIT_ULL(i);
+			bit++;
+		}
+	}
+
+	if (hweight64(ts_mask) != hweight64(map)) {
+		dev_err(qmc_hdlc->dev, "Cannot translate timeslots 0x%llx -> (0x%llx,0x%llx)\n",
+			map, ts_mask_avail, ts_mask);
+		return -EINVAL;
+	}
+
+	ts_info->tx_ts_mask = ts_mask;
+	ts_info->rx_ts_mask = ts_mask;
+	return 0;
+}
+
+static int qmc_hdlc_xlate_ts_info(struct qmc_hdlc *qmc_hdlc,
+				  const struct qmc_chan_ts_info *ts_info, u32 *slot_map)
+{
+	u64 ts_mask_avail;
+	unsigned int bit;
+	unsigned int i;
+	u64 ts_mask;
+	u64 map;
+
+	/* Tx and Rx masks must be identical */
+	if (ts_info->rx_ts_mask_avail != ts_info->tx_ts_mask_avail) {
+		dev_err(qmc_hdlc->dev, "tx and rx available timeslots mismatch (0x%llx, 0x%llx)\n",
+			ts_info->rx_ts_mask_avail, ts_info->tx_ts_mask_avail);
+		return -EINVAL;
+	}
+	if (ts_info->rx_ts_mask != ts_info->tx_ts_mask) {
+		dev_err(qmc_hdlc->dev, "tx and rx timeslots mismatch (0x%llx, 0x%llx)\n",
+			ts_info->rx_ts_mask, ts_info->tx_ts_mask);
+		return -EINVAL;
+	}
+
+	ts_mask_avail = ts_info->rx_ts_mask_avail;
+	ts_mask = ts_info->rx_ts_mask;
+	map = 0;
+	bit = 0;
+	for (i = 0; i < 64; i++) {
+		if (ts_mask_avail & BIT_ULL(i)) {
+			if (ts_mask & BIT_ULL(i))
+				map |= BIT_ULL(bit);
+			bit++;
+		}
+	}
+
+	if (hweight64(ts_mask) != hweight64(map)) {
+		dev_err(qmc_hdlc->dev, "Cannot translate timeslots (0x%llx,0x%llx) -> 0x%llx\n",
+			ts_mask_avail, ts_mask, map);
+		return -EINVAL;
+	}
+
+	if (map >= BIT_ULL(32)) {
+		dev_err(qmc_hdlc->dev, "Slot map out of 32bit (0x%llx,0x%llx) -> 0x%llx\n",
+			ts_mask_avail, ts_mask, map);
+		return -EINVAL;
+	}
+
+	*slot_map = map;
+	return 0;
+}
+
+static int qmc_hdlc_set_iface(struct qmc_hdlc *qmc_hdlc, int if_iface, const te1_settings *te1)
+{
+	struct qmc_chan_ts_info ts_info;
+	int ret;
+
+	ret = qmc_chan_get_ts_info(qmc_hdlc->qmc_chan, &ts_info);
+	if (ret) {
+		dev_err(qmc_hdlc->dev, "get QMC channel ts info failed %d\n", ret);
+		return ret;
+	}
+	ret = qmc_hdlc_xlate_slot_map(qmc_hdlc, te1->slot_map, &ts_info);
+	if (ret)
+		return ret;
+
+	ret = qmc_chan_set_ts_info(qmc_hdlc->qmc_chan, &ts_info);
+	if (ret) {
+		dev_err(qmc_hdlc->dev, "set QMC channel ts info failed %d\n", ret);
+		return ret;
+	}
+
+	qmc_hdlc->slot_map = te1->slot_map;
+
+	return 0;
+}
+
+static int qmc_hdlc_ioctl(struct net_device *netdev, struct if_settings *ifs)
+{
+	struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
+	te1_settings te1;
+
+	switch (ifs->type) {
+	case IF_GET_IFACE:
+		ifs->type = IF_IFACE_E1;
+		if (ifs->size < sizeof(te1)) {
+			if (!ifs->size)
+				return 0; /* only type requested */
+
+			ifs->size = sizeof(te1); /* data size wanted */
+			return -ENOBUFS;
+		}
+
+		memset(&te1, 0, sizeof(te1));
+
+		/* Update slot_map */
+		te1.slot_map = qmc_hdlc->slot_map;
+
+		if (copy_to_user(ifs->ifs_ifsu.te1, &te1, sizeof(te1)))
+			return -EFAULT;
+		return 0;
+
+	case IF_IFACE_E1:
+	case IF_IFACE_T1:
+		if (!capable(CAP_NET_ADMIN))
+			return -EPERM;
+
+		if (netdev->flags & IFF_UP)
+			return -EBUSY;
+
+		if (copy_from_user(&te1, ifs->ifs_ifsu.te1, sizeof(te1)))
+			return -EFAULT;
+
+		return qmc_hdlc_set_iface(qmc_hdlc, ifs->type, &te1);
+
+	default:
+		return hdlc_ioctl(netdev, ifs);
+	}
+}
+
 static int qmc_hdlc_open(struct net_device *netdev)
 {
 	struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
@@ -328,13 +485,14 @@ static const struct net_device_ops qmc_hdlc_netdev_ops = {
 	.ndo_open       = qmc_hdlc_open,
 	.ndo_stop       = qmc_hdlc_close,
 	.ndo_start_xmit = hdlc_start_xmit,
-	.ndo_siocwandev	= hdlc_ioctl,
+	.ndo_siocwandev = qmc_hdlc_ioctl,
 };
 
 static int qmc_hdlc_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	struct qmc_hdlc *qmc_hdlc;
+	struct qmc_chan_ts_info ts_info;
 	struct qmc_chan_info info;
 	hdlc_device *hdlc;
 	int ret;
@@ -364,6 +522,15 @@ static int qmc_hdlc_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
+	ret = qmc_chan_get_ts_info(qmc_hdlc->qmc_chan, &ts_info);
+	if (ret) {
+		dev_err(qmc_hdlc->dev, "get QMC channel ts info failed %d\n", ret);
+		return ret;
+	}
+	ret = qmc_hdlc_xlate_ts_info(qmc_hdlc, &ts_info, &qmc_hdlc->slot_map);
+	if (ret)
+		return ret;
+
 	qmc_hdlc->netdev = alloc_hdlcdev(qmc_hdlc);
 	if (!qmc_hdlc->netdev) {
 		dev_err(qmc_hdlc->dev, "failed to alloc hdlc dev\n");
-- 
2.43.0