2024-02-22 14:22:44

by Herve Codina

[permalink] [raw]
Subject: [PATCH v4 0/5] Add support for QMC HDLC

Hi,

This series introduces the QMC HDLC support.

Patches were previously sent as part of a full feature series and were
previously reviewed in that context:
"Add support for QMC HDLC, framer infrastructure and PEF2256 framer" [1]

In order to ease the merge, the full feature series has been split and
needed parts were merged in v6.8-rc1:
- "Prepare the PowerQUICC QMC and TSA for the HDLC QMC driver" [2]
- "Add support for framer infrastructure and PEF2256 framer" [3]

This series contains patches related to the QMC HDLC part (QMC HDLC
driver):
- Introduce the QMC HDLC driver (patches 1 and 2)
- Add timeslots change support in QMC HDLC (patch 3)
- Add framer support as a framer consumer in QMC HDLC (patch 4)

Compare to the original full feature series, a modification was done on
patch 3 in order to use a coherent prefix in the commit title.

I kept the patches unsquashed as they were previously sent and reviewed.
Of course, I can squash them if needed.

Compared to the previous iteration:
https://lore.kernel.org/linux-kernel/[email protected]/
this v4 series mainly:
- Introduces and use bitmap_{scatter,gather}().

Best regards,
Hervé

[1]: https://lore.kernel.org/linux-kernel/[email protected]/
[2]: https://lore.kernel.org/linux-kernel/[email protected]/
[3]: https://lore.kernel.org/linux-kernel/[email protected]/

Changes v3 -> v4
- Patch 1
Remove of.h and of_platform.h includes, add mod_devicetable.h.
Add a blank line in the includes list.

- Path 2
No changes.

- v3 patches 3 and 4 removed

- Patch 3 (new patch in v4)
Introduce bitmap_{scatter,gather}() based on the original patch done
by Andy Shevchenko.
Address comments already done on the original patch:
https://lore.kernel.org/lkml/[email protected]/
- Removed the returned values.
- Used 'unsigned int' for all indexes.
- Added a 'visual' description of the operations in kernel-doc.
- Described the relationship between bitmap_scatter() and
bitmap_gather().
- Moved bitmap_{scatter,gather}() to the bitmap.h file.
- Improved bitmap_{scatter,gather}() test.
- Reworked the commit log.

- Patch 4 (v3 patch 5)
Use bitmap_{scatter,gather}()

- Patches 5 (v3 patch 6)
No changes.

Changes v2 -> v3
- Patch 1
Remove 'inline' function specifier from .c file.
Fix a bug introduced when added WARN_ONCE(). The warn condition must
be desc->skb (descriptor used) instead of !desc->skb.
Remove a lock/unlock section locking the entire qmc_hdlc_xmit()
function.

- Patch 5
Use bitmap_from_u64() everywhere instead of bitmap_from_arr32() and
bitmap_from_arr64().

Changes v1 -> v2
- Patch 1
Use the same qmc_hdlc initialisation in qmc_hcld_recv_complete()
than the one present in qmc_hcld_xmit_complete().
Use WARN_ONCE()

- Patch 3 (new patch in v2)
Make bitmap_onto() available to users

- Patch 4 (new patch in v2)
Introduce bitmap_off()

- Patch 5 (patch 3 in v1)
Use bitmap_*() functions

- Patch 6 (patch 4 in v1)
No changes

Changes compare to the full feature series:
- Patch 3
Use 'net: wan: fsl_qmc_hdlc:' as commit title prefix

Patches extracted:
- Patch 1 : full feature series patch 7
- Patch 2 : full feature series patch 8
- Patch 3 : full feature series patch 20
- Patch 4 : full feature series patch 27

Andy Shevchenko (1):
lib/bitmap: Introduce bitmap_scatter() and bitmap_gather() helpers

Herve Codina (4):
net: wan: Add support for QMC HDLC
MAINTAINERS: Add the Freescale QMC HDLC driver entry
net: wan: fsl_qmc_hdlc: Add runtime timeslots changes support
net: wan: fsl_qmc_hdlc: Add framer support

MAINTAINERS | 7 +
drivers/net/wan/Kconfig | 12 +
drivers/net/wan/Makefile | 1 +
drivers/net/wan/fsl_qmc_hdlc.c | 807 +++++++++++++++++++++++++++++++++
include/linux/bitmap.h | 101 +++++
lib/test_bitmap.c | 42 ++
6 files changed, 970 insertions(+)
create mode 100644 drivers/net/wan/fsl_qmc_hdlc.c

--
2.43.0



2024-02-22 14:23:05

by Herve Codina

[permalink] [raw]
Subject: [PATCH v4 1/5] net: wan: Add support for QMC HDLC

The QMC HDLC driver provides support for HDLC using the QMC (QUICC
Multichannel Controller) to transfer the HDLC data.

Signed-off-by: Herve Codina <[email protected]>
Reviewed-by: Christophe Leroy <[email protected]>
Acked-by: Jakub Kicinski <[email protected]>
---
drivers/net/wan/Kconfig | 12 +
drivers/net/wan/Makefile | 1 +
drivers/net/wan/fsl_qmc_hdlc.c | 426 +++++++++++++++++++++++++++++++++
3 files changed, 439 insertions(+)
create mode 100644 drivers/net/wan/fsl_qmc_hdlc.c

diff --git a/drivers/net/wan/Kconfig b/drivers/net/wan/Kconfig
index 7dda87756d3f..31ab2136cdf1 100644
--- a/drivers/net/wan/Kconfig
+++ b/drivers/net/wan/Kconfig
@@ -197,6 +197,18 @@ config FARSYNC
To compile this driver as a module, choose M here: the
module will be called farsync.

+config FSL_QMC_HDLC
+ tristate "Freescale QMC HDLC support"
+ depends on HDLC
+ depends on CPM_QMC
+ help
+ HDLC support using the Freescale QUICC Multichannel Controller (QMC).
+
+ To compile this driver as a module, choose M here: the
+ module will be called fsl_qmc_hdlc.
+
+ If unsure, say N.
+
config FSL_UCC_HDLC
tristate "Freescale QUICC Engine HDLC support"
depends on HDLC
diff --git a/drivers/net/wan/Makefile b/drivers/net/wan/Makefile
index 8119b49d1da9..00e9b7ee1e01 100644
--- a/drivers/net/wan/Makefile
+++ b/drivers/net/wan/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_WANXL) += wanxl.o
obj-$(CONFIG_PCI200SYN) += pci200syn.o
obj-$(CONFIG_PC300TOO) += pc300too.o
obj-$(CONFIG_IXP4XX_HSS) += ixp4xx_hss.o
+obj-$(CONFIG_FSL_QMC_HDLC) += fsl_qmc_hdlc.o
obj-$(CONFIG_FSL_UCC_HDLC) += fsl_ucc_hdlc.o
obj-$(CONFIG_SLIC_DS26522) += slic_ds26522.o

diff --git a/drivers/net/wan/fsl_qmc_hdlc.c b/drivers/net/wan/fsl_qmc_hdlc.c
new file mode 100644
index 000000000000..ec08ab217a72
--- /dev/null
+++ b/drivers/net/wan/fsl_qmc_hdlc.c
@@ -0,0 +1,426 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Freescale QMC HDLC Device Driver
+ *
+ * Copyright 2023 CS GROUP France
+ *
+ * Author: Herve Codina <[email protected]>
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/hdlc.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <soc/fsl/qe/qmc.h>
+
+struct qmc_hdlc_desc {
+ struct net_device *netdev;
+ struct sk_buff *skb; /* NULL if the descriptor is not in use */
+ dma_addr_t dma_addr;
+ size_t dma_size;
+};
+
+struct qmc_hdlc {
+ struct device *dev;
+ struct qmc_chan *qmc_chan;
+ struct net_device *netdev;
+ bool is_crc32;
+ spinlock_t tx_lock; /* Protect tx descriptors */
+ struct qmc_hdlc_desc tx_descs[8];
+ unsigned int tx_out;
+ struct qmc_hdlc_desc rx_descs[4];
+};
+
+static struct qmc_hdlc *netdev_to_qmc_hdlc(struct net_device *netdev)
+{
+ return dev_to_hdlc(netdev)->priv;
+}
+
+static int qmc_hdlc_recv_queue(struct qmc_hdlc *qmc_hdlc, struct qmc_hdlc_desc *desc, size_t size);
+
+#define QMC_HDLC_RX_ERROR_FLAGS (QMC_RX_FLAG_HDLC_OVF | \
+ QMC_RX_FLAG_HDLC_UNA | \
+ QMC_RX_FLAG_HDLC_ABORT | \
+ QMC_RX_FLAG_HDLC_CRC)
+
+static void qmc_hcld_recv_complete(void *context, size_t length, unsigned int flags)
+{
+ struct qmc_hdlc_desc *desc = context;
+ struct net_device *netdev = desc->netdev;
+ struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
+ int ret;
+
+ dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_FROM_DEVICE);
+
+ if (flags & QMC_HDLC_RX_ERROR_FLAGS) {
+ netdev->stats.rx_errors++;
+ if (flags & QMC_RX_FLAG_HDLC_OVF) /* Data overflow */
+ netdev->stats.rx_over_errors++;
+ if (flags & QMC_RX_FLAG_HDLC_UNA) /* bits received not multiple of 8 */
+ netdev->stats.rx_frame_errors++;
+ if (flags & QMC_RX_FLAG_HDLC_ABORT) /* Received an abort sequence */
+ netdev->stats.rx_frame_errors++;
+ if (flags & QMC_RX_FLAG_HDLC_CRC) /* CRC error */
+ netdev->stats.rx_crc_errors++;
+ kfree_skb(desc->skb);
+ } else {
+ netdev->stats.rx_packets++;
+ netdev->stats.rx_bytes += length;
+
+ skb_put(desc->skb, length);
+ desc->skb->protocol = hdlc_type_trans(desc->skb, netdev);
+ netif_rx(desc->skb);
+ }
+
+ /* Re-queue a transfer using the same descriptor */
+ ret = qmc_hdlc_recv_queue(qmc_hdlc, desc, desc->dma_size);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "queue recv desc failed (%d)\n", ret);
+ netdev->stats.rx_errors++;
+ }
+}
+
+static int qmc_hdlc_recv_queue(struct qmc_hdlc *qmc_hdlc, struct qmc_hdlc_desc *desc, size_t size)
+{
+ int ret;
+
+ desc->skb = dev_alloc_skb(size);
+ if (!desc->skb)
+ return -ENOMEM;
+
+ desc->dma_size = size;
+ desc->dma_addr = dma_map_single(qmc_hdlc->dev, desc->skb->data,
+ desc->dma_size, DMA_FROM_DEVICE);
+ ret = dma_mapping_error(qmc_hdlc->dev, desc->dma_addr);
+ if (ret)
+ goto free_skb;
+
+ ret = qmc_chan_read_submit(qmc_hdlc->qmc_chan, desc->dma_addr, desc->dma_size,
+ qmc_hcld_recv_complete, desc);
+ if (ret)
+ goto dma_unmap;
+
+ return 0;
+
+dma_unmap:
+ dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_FROM_DEVICE);
+free_skb:
+ kfree_skb(desc->skb);
+ desc->skb = NULL;
+ return ret;
+}
+
+static void qmc_hdlc_xmit_complete(void *context)
+{
+ struct qmc_hdlc_desc *desc = context;
+ struct net_device *netdev = desc->netdev;
+ struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
+ struct sk_buff *skb;
+ unsigned long flags;
+
+ spin_lock_irqsave(&qmc_hdlc->tx_lock, flags);
+ dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_TO_DEVICE);
+ skb = desc->skb;
+ desc->skb = NULL; /* Release the descriptor */
+ if (netif_queue_stopped(netdev))
+ netif_wake_queue(netdev);
+ spin_unlock_irqrestore(&qmc_hdlc->tx_lock, flags);
+
+ netdev->stats.tx_packets++;
+ netdev->stats.tx_bytes += skb->len;
+
+ dev_consume_skb_any(skb);
+}
+
+static int qmc_hdlc_xmit_queue(struct qmc_hdlc *qmc_hdlc, struct qmc_hdlc_desc *desc)
+{
+ int ret;
+
+ desc->dma_addr = dma_map_single(qmc_hdlc->dev, desc->skb->data,
+ desc->dma_size, DMA_TO_DEVICE);
+ ret = dma_mapping_error(qmc_hdlc->dev, desc->dma_addr);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "failed to map skb\n");
+ return ret;
+ }
+
+ ret = qmc_chan_write_submit(qmc_hdlc->qmc_chan, desc->dma_addr, desc->dma_size,
+ qmc_hdlc_xmit_complete, desc);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "qmc chan write returns %d\n", ret);
+ dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_TO_DEVICE);
+ return ret;
+ }
+
+ return 0;
+}
+
+static netdev_tx_t qmc_hdlc_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+ struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
+ struct qmc_hdlc_desc *desc;
+ unsigned long flags;
+ int err;
+ int ret;
+
+ spin_lock_irqsave(&qmc_hdlc->tx_lock, flags);
+
+ desc = &qmc_hdlc->tx_descs[qmc_hdlc->tx_out];
+ if (WARN_ONCE(desc->skb, "No tx descriptors available\n")) {
+ /* Should never happen.
+ * Previous xmit should have already stopped the queue.
+ */
+ netif_stop_queue(netdev);
+ ret = NETDEV_TX_BUSY;
+ goto end;
+ }
+
+ desc->netdev = netdev;
+ desc->dma_size = skb->len;
+ desc->skb = skb;
+ err = qmc_hdlc_xmit_queue(qmc_hdlc, desc);
+ if (err) {
+ desc->skb = NULL; /* Release the descriptor */
+ if (err == -EBUSY) {
+ netif_stop_queue(netdev);
+ ret = NETDEV_TX_BUSY;
+ goto end;
+ }
+ dev_kfree_skb(skb);
+ netdev->stats.tx_dropped++;
+ ret = NETDEV_TX_OK;
+ goto end;
+ }
+
+ qmc_hdlc->tx_out = (qmc_hdlc->tx_out + 1) % ARRAY_SIZE(qmc_hdlc->tx_descs);
+
+ if (qmc_hdlc->tx_descs[qmc_hdlc->tx_out].skb)
+ netif_stop_queue(netdev);
+
+ ret = NETDEV_TX_OK;
+end:
+ spin_unlock_irqrestore(&qmc_hdlc->tx_lock, flags);
+ return ret;
+}
+
+static int qmc_hdlc_open(struct net_device *netdev)
+{
+ struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
+ struct qmc_chan_param chan_param;
+ struct qmc_hdlc_desc *desc;
+ int ret;
+ int i;
+
+ ret = hdlc_open(netdev);
+ if (ret)
+ return ret;
+
+ chan_param.mode = QMC_HDLC;
+ /* HDLC_MAX_MRU + 4 for the CRC
+ * HDLC_MAX_MRU + 4 + 8 for the CRC and some extraspace needed by the QMC
+ */
+ chan_param.hdlc.max_rx_buf_size = HDLC_MAX_MRU + 4 + 8;
+ chan_param.hdlc.max_rx_frame_size = HDLC_MAX_MRU + 4;
+ chan_param.hdlc.is_crc32 = qmc_hdlc->is_crc32;
+ ret = qmc_chan_set_param(qmc_hdlc->qmc_chan, &chan_param);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "failed to set param (%d)\n", ret);
+ goto hdlc_close;
+ }
+
+ /* Queue as many recv descriptors as possible */
+ for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) {
+ desc = &qmc_hdlc->rx_descs[i];
+
+ desc->netdev = netdev;
+ ret = qmc_hdlc_recv_queue(qmc_hdlc, desc, chan_param.hdlc.max_rx_buf_size);
+ if (ret) {
+ if (ret == -EBUSY && i != 0)
+ break; /* We use all the QMC chan capability */
+ goto free_desc;
+ }
+ }
+
+ ret = qmc_chan_start(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "qmc chan start failed (%d)\n", ret);
+ goto free_desc;
+ }
+
+ netif_start_queue(netdev);
+
+ return 0;
+
+free_desc:
+ qmc_chan_reset(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
+ for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) {
+ desc = &qmc_hdlc->rx_descs[i];
+ if (!desc->skb)
+ continue;
+ dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size,
+ DMA_FROM_DEVICE);
+ kfree_skb(desc->skb);
+ desc->skb = NULL;
+ }
+hdlc_close:
+ hdlc_close(netdev);
+ return ret;
+}
+
+static int qmc_hdlc_close(struct net_device *netdev)
+{
+ struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
+ struct qmc_hdlc_desc *desc;
+ int i;
+
+ qmc_chan_stop(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
+ qmc_chan_reset(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
+
+ netif_stop_queue(netdev);
+
+ for (i = 0; i < ARRAY_SIZE(qmc_hdlc->tx_descs); i++) {
+ desc = &qmc_hdlc->tx_descs[i];
+ if (!desc->skb)
+ continue;
+ dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size,
+ DMA_TO_DEVICE);
+ kfree_skb(desc->skb);
+ desc->skb = NULL;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) {
+ desc = &qmc_hdlc->rx_descs[i];
+ if (!desc->skb)
+ continue;
+ dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size,
+ DMA_FROM_DEVICE);
+ kfree_skb(desc->skb);
+ desc->skb = NULL;
+ }
+
+ hdlc_close(netdev);
+ return 0;
+}
+
+static int qmc_hdlc_attach(struct net_device *netdev, unsigned short encoding,
+ unsigned short parity)
+{
+ struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
+
+ if (encoding != ENCODING_NRZ)
+ return -EINVAL;
+
+ switch (parity) {
+ case PARITY_CRC16_PR1_CCITT:
+ qmc_hdlc->is_crc32 = false;
+ break;
+ case PARITY_CRC32_PR1_CCITT:
+ qmc_hdlc->is_crc32 = true;
+ break;
+ default:
+ dev_err(qmc_hdlc->dev, "unsupported parity %u\n", parity);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+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,
+};
+
+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_info info;
+ hdlc_device *hdlc;
+ int ret;
+
+ qmc_hdlc = devm_kzalloc(&pdev->dev, sizeof(*qmc_hdlc), GFP_KERNEL);
+ if (!qmc_hdlc)
+ return -ENOMEM;
+
+ qmc_hdlc->dev = &pdev->dev;
+ spin_lock_init(&qmc_hdlc->tx_lock);
+
+ qmc_hdlc->qmc_chan = devm_qmc_chan_get_bychild(qmc_hdlc->dev, np);
+ if (IS_ERR(qmc_hdlc->qmc_chan)) {
+ ret = PTR_ERR(qmc_hdlc->qmc_chan);
+ return dev_err_probe(qmc_hdlc->dev, ret, "get QMC channel failed\n");
+ }
+
+ ret = qmc_chan_get_info(qmc_hdlc->qmc_chan, &info);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "get QMC channel info failed %d\n", ret);
+ return ret;
+ }
+
+ if (info.mode != QMC_HDLC) {
+ dev_err(qmc_hdlc->dev, "QMC chan mode %d is not QMC_HDLC\n",
+ info.mode);
+ return -EINVAL;
+ }
+
+ qmc_hdlc->netdev = alloc_hdlcdev(qmc_hdlc);
+ if (!qmc_hdlc->netdev) {
+ dev_err(qmc_hdlc->dev, "failed to alloc hdlc dev\n");
+ return -ENOMEM;
+ }
+
+ hdlc = dev_to_hdlc(qmc_hdlc->netdev);
+ hdlc->attach = qmc_hdlc_attach;
+ hdlc->xmit = qmc_hdlc_xmit;
+ SET_NETDEV_DEV(qmc_hdlc->netdev, qmc_hdlc->dev);
+ qmc_hdlc->netdev->tx_queue_len = ARRAY_SIZE(qmc_hdlc->tx_descs);
+ qmc_hdlc->netdev->netdev_ops = &qmc_hdlc_netdev_ops;
+ ret = register_hdlc_device(qmc_hdlc->netdev);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "failed to register hdlc device (%d)\n", ret);
+ goto free_netdev;
+ }
+
+ platform_set_drvdata(pdev, qmc_hdlc);
+
+ return 0;
+
+free_netdev:
+ free_netdev(qmc_hdlc->netdev);
+ return ret;
+}
+
+static int qmc_hdlc_remove(struct platform_device *pdev)
+{
+ struct qmc_hdlc *qmc_hdlc = platform_get_drvdata(pdev);
+
+ unregister_hdlc_device(qmc_hdlc->netdev);
+ free_netdev(qmc_hdlc->netdev);
+
+ return 0;
+}
+
+static const struct of_device_id qmc_hdlc_id_table[] = {
+ { .compatible = "fsl,qmc-hdlc" },
+ {} /* sentinel */
+};
+MODULE_DEVICE_TABLE(of, qmc_hdlc_driver);
+
+static struct platform_driver qmc_hdlc_driver = {
+ .driver = {
+ .name = "fsl-qmc-hdlc",
+ .of_match_table = qmc_hdlc_id_table,
+ },
+ .probe = qmc_hdlc_probe,
+ .remove = qmc_hdlc_remove,
+};
+module_platform_driver(qmc_hdlc_driver);
+
+MODULE_AUTHOR("Herve Codina <[email protected]>");
+MODULE_DESCRIPTION("QMC HDLC driver");
+MODULE_LICENSE("GPL");
--
2.43.0


2024-02-22 14:23:13

by Herve Codina

[permalink] [raw]
Subject: [PATCH v4 2/5] MAINTAINERS: Add the Freescale QMC HDLC driver entry

After contributing the driver, add myself as the maintainer for the
Freescale QMC HDLC driver.

Signed-off-by: Herve Codina <[email protected]>
---
MAINTAINERS | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 8d1052fa6a69..15cd3a8e5866 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8584,6 +8584,13 @@ F: Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-scc-qmc.yaml
F: drivers/soc/fsl/qe/qmc.c
F: include/soc/fsl/qe/qmc.h

+FREESCALE QUICC ENGINE QMC HDLC DRIVER
+M: Herve Codina <[email protected]>
+L: [email protected]
+L: [email protected]
+S: Maintained
+F: drivers/net/wan/fsl_qmc_hdlc.c
+
FREESCALE QUICC ENGINE TSA DRIVER
M: Herve Codina <[email protected]>
L: [email protected]
--
2.43.0


2024-02-22 14:23:37

by Herve Codina

[permalink] [raw]
Subject: [PATCH v4 3/5] lib/bitmap: Introduce bitmap_scatter() and bitmap_gather() helpers

From: Andy Shevchenko <[email protected]>

These helpers scatters or gathers a bitmap with the help of the mask
position bits parameter.

bitmap_scatter() does the following:
src: 0000000001011010
||||||
+------+|||||
| +----+||||
| |+----+|||
| || +-+||
| || | ||
mask: ...v..vv...v..vv
...0..11...0..10
dst: 0000001100000010

and bitmap_gather() performs this one:
mask: ...v..vv...v..vv
src: 0000001100000010
^ ^^ ^ 0
| || | 10
| || > 010
| |+--> 1010
| +--> 11010
+----> 011010
dst: 0000000000011010

bitmap_gather() can the seen as the reverse bitmap_scatter() operation.

The original work was done by Andy Shevchenko.

Signed-off-by: Andy Shevchenko <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Signed-off-by: Herve Codina <[email protected]>
---
Yury, Andy, I hope I correctly took into accounts the comments
reveived on Andy's v1 series and found good compromise to satisfy
your different point of view.

include/linux/bitmap.h | 101 +++++++++++++++++++++++++++++++++++++++++
lib/test_bitmap.c | 42 +++++++++++++++++
2 files changed, 143 insertions(+)

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 99451431e4d6..a171030ff71c 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -62,6 +62,8 @@ struct device;
* bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
* bitmap_cut(dst, src, first, n, nbits) Cut n bits from first, copy rest
* bitmap_replace(dst, old, new, mask, nbits) *dst = (*old & ~(*mask)) | (*new & *mask)
+ * bitmap_scatter(dst, src, mask, nbits) *dst = map(dense, sparse)(src)
+ * bitmap_gather(dst, src, mask, nbits) *dst = map(sparse, dense)(src)
* bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
* bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
* bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
@@ -487,6 +489,105 @@ static inline void bitmap_replace(unsigned long *dst,
__bitmap_replace(dst, old, new, mask, nbits);
}

+/**
+ * bitmap_scatter - Scatter a bitmap according to the given mask
+ * @dst: scattered bitmap
+ * @src: gathered bitmap
+ * @mask: mask representing bits to assign to in the scattered bitmap
+ * @nbits: number of bits in each of these bitmaps
+ *
+ * Scatters bitmap with sequential bits according to the given @mask.
+ *
+ * Example:
+ * If @src bitmap = 0x005a, with @mask = 0x1313, @dst will be 0x0302.
+ *
+ * Or in binary form
+ * @src @mask @dst
+ * 0000000001011010 0001001100010011 0000001100000010
+ *
+ * (Bits 0, 1, 2, 3, 4, 5 are copied to the bits 0, 1, 4, 8, 9, 12)
+ *
+ * A more 'visual' description of the operation:
+ * src: 0000000001011010
+ * ||||||
+ * +------+|||||
+ * | +----+||||
+ * | |+----+|||
+ * | || +-+||
+ * | || | ||
+ * mask: ...v..vv...v..vv
+ * ...0..11...0..10
+ * dst: 0000001100000010
+ *
+ * A relationship exists between bitmap_scatter() and bitmap_gather().
+ * bitmap_gather() can be seen as the 'reverse' bitmap_scatter() operation.
+ * See bitmap_scatter() for details related to this relationship.
+ */
+static inline void bitmap_scatter(unsigned long *dst, const unsigned long *src,
+ const unsigned long *mask, unsigned int nbits)
+{
+ unsigned int n = 0;
+ unsigned int bit;
+
+ bitmap_zero(dst, nbits);
+
+ for_each_set_bit(bit, mask, nbits)
+ __assign_bit(bit, dst, test_bit(n++, src));
+}
+
+/**
+ * bitmap_gather - Gather a bitmap according to given mask
+ * @dst: gathered bitmap
+ * @src: scattered bitmap
+ * @mask: mask representing bits to extract from in the scattered bitmap
+ * @nbits: number of bits in each of these bitmaps
+ *
+ * Gathers bitmap with sparse bits according to the given @mask.
+ *
+ * Example:
+ * If @src bitmap = 0x0302, with @mask = 0x1313, @dst will be 0x001a.
+ *
+ * Or in binary form
+ * @src @mask @dst
+ * 0000001100000010 0001001100010011 0000000000011010
+ *
+ * (Bits 0, 1, 4, 8, 9, 12 are copied to the bits 0, 1, 2, 3, 4, 5)
+ *
+ * A more 'visual' description of the operation:
+ * mask: ...v..vv...v..vv
+ * src: 0000001100000010
+ * ^ ^^ ^ 0
+ * | || | 10
+ * | || > 010
+ * | |+--> 1010
+ * | +--> 11010
+ * +----> 011010
+ * dst: 0000000000011010
+ *
+ * A relationship exists between bitmap_gather() and bitmap_scatter() (See
+ * bitmap_scatter() for the bitmap scatter detailed operations).
+ * Suppose scattered computed using bitmap_scatter(scattered, src, mask, n).
+ * The operation bitmap_gather(result, scattered, mask, n) leads to a result
+ * equal or equivalent to src.
+ *
+ * The result can be 'equivalent' because bitmap_scatter() and bitmap_gather()
+ * are not bijective.
+ * The result and src values are equivalent in that sense that a call to
+ * bitmap_scatter(res, src, mask, n) and a call to bitmap_scatter(res, result,
+ * mask, n) will lead to the same res value.
+ */
+static inline void bitmap_gather(unsigned long *dst, const unsigned long *src,
+ const unsigned long *mask, unsigned int nbits)
+{
+ unsigned int n = 0;
+ unsigned int bit;
+
+ bitmap_zero(dst, nbits);
+
+ for_each_set_bit(bit, mask, nbits)
+ __assign_bit(n++, dst, test_bit(bit, src));
+}
+
static inline void bitmap_next_set_region(unsigned long *bitmap,
unsigned int *rs, unsigned int *re,
unsigned int end)
diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index 65f22c2578b0..6b2b33579f56 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -380,6 +380,47 @@ static void __init test_replace(void)
expect_eq_bitmap(bmap, exp3_1_0, nbits);
}

+static const unsigned long sg_mask[] __initconst = {
+ BITMAP_FROM_U64(0x000000000000035aULL),
+};
+
+static const unsigned long sg_src[] __initconst = {
+ BITMAP_FROM_U64(0x0000000000000667ULL),
+};
+
+static const unsigned long sg_gather_exp[] __initconst = {
+ BITMAP_FROM_U64(0x0000000000000029ULL),
+};
+
+static const unsigned long sg_scatter_exp[] __initconst = {
+ BITMAP_FROM_U64(0x000000000000021aULL),
+};
+
+static void __init test_bitmap_sg(void)
+{
+ unsigned int nbits = 64;
+ DECLARE_BITMAP(bmap_gather, 100);
+ DECLARE_BITMAP(bmap_scatter, 100);
+ DECLARE_BITMAP(bmap_tmp, 100);
+ DECLARE_BITMAP(bmap_res, 100);
+
+ /* Simple gather call */
+ bitmap_zero(bmap_gather, 100);
+ bitmap_gather(bmap_gather, sg_src, sg_mask, nbits);
+ expect_eq_bitmap(sg_gather_exp, bmap_gather, nbits);
+
+ /* Simple scatter call */
+ bitmap_zero(bmap_scatter, 100);
+ bitmap_scatter(bmap_scatter, sg_src, sg_mask, nbits);
+ expect_eq_bitmap(sg_scatter_exp, bmap_scatter, nbits);
+
+ /* Scatter/gather relationship */
+ bitmap_zero(bmap_tmp, 100);
+ bitmap_gather(bmap_tmp, bmap_scatter, sg_mask, nbits);
+ bitmap_scatter(bmap_res, bmap_tmp, sg_mask, nbits);
+ expect_eq_bitmap(bmap_scatter, bmap_res, nbits);
+}
+
#define PARSE_TIME 0x1
#define NO_LEN 0x2

@@ -1252,6 +1293,7 @@ static void __init selftest(void)
test_copy();
test_bitmap_region();
test_replace();
+ test_bitmap_sg();
test_bitmap_arr32();
test_bitmap_arr64();
test_bitmap_parse();
--
2.43.0


2024-02-22 14:23:54

by Herve Codina

[permalink] [raw]
Subject: [PATCH v4 4/5] net: wan: fsl_qmc_hdlc: Add runtime timeslots changes support

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 <[email protected]>
Reviewed-by: Christophe Leroy <[email protected]>
Acked-by: Jakub Kicinski <[email protected]>
---
drivers/net/wan/fsl_qmc_hdlc.c | 152 ++++++++++++++++++++++++++++++++-
1 file changed, 151 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wan/fsl_qmc_hdlc.c b/drivers/net/wan/fsl_qmc_hdlc.c
index ec08ab217a72..1b7f1d5af273 100644
--- a/drivers/net/wan/fsl_qmc_hdlc.c
+++ b/drivers/net/wan/fsl_qmc_hdlc.c
@@ -7,6 +7,7 @@
* Author: Herve Codina <[email protected]>
*/

+#include <linux/bitmap.h>
#include <linux/dma-mapping.h>
#include <linux/hdlc.h>
#include <linux/mod_devicetable.h>
@@ -32,6 +33,7 @@ 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 struct qmc_hdlc *netdev_to_qmc_hdlc(struct net_device *netdev)
@@ -206,6 +208,144 @@ static netdev_tx_t qmc_hdlc_xmit(struct sk_buff *skb, struct net_device *netdev)
return ret;
}

+static int qmc_hdlc_xlate_slot_map(struct qmc_hdlc *qmc_hdlc,
+ u32 slot_map, struct qmc_chan_ts_info *ts_info)
+{
+ DECLARE_BITMAP(ts_mask_avail, 64);
+ DECLARE_BITMAP(ts_mask, 64);
+ DECLARE_BITMAP(map, 64);
+
+ /* Tx and Rx available 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;
+ }
+
+ bitmap_from_u64(ts_mask_avail, ts_info->rx_ts_mask_avail);
+ bitmap_from_u64(map, slot_map);
+ bitmap_scatter(ts_mask, map, ts_mask_avail, 64);
+
+ if (bitmap_weight(ts_mask, 64) != bitmap_weight(map, 64)) {
+ dev_err(qmc_hdlc->dev, "Cannot translate timeslots %*pb -> (%*pb, %*pb)\n",
+ 64, map, 64, ts_mask_avail, 64, ts_mask);
+ return -EINVAL;
+ }
+
+ bitmap_to_arr64(&ts_info->tx_ts_mask, ts_mask, 64);
+ ts_info->rx_ts_mask = ts_info->tx_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)
+{
+ DECLARE_BITMAP(ts_mask_avail, 64);
+ DECLARE_BITMAP(ts_mask, 64);
+ DECLARE_BITMAP(map, 64);
+ u32 array32[2];
+
+ /* Tx and Rx masks and available 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;
+ }
+
+ bitmap_from_u64(ts_mask_avail, ts_info->rx_ts_mask_avail);
+ bitmap_from_u64(ts_mask, ts_info->rx_ts_mask);
+ bitmap_gather(map, ts_mask, ts_mask_avail, 64);
+
+ if (bitmap_weight(ts_mask, 64) != bitmap_weight(map, 64)) {
+ dev_err(qmc_hdlc->dev, "Cannot translate timeslots (%*pb, %*pb) -> %*pb\n",
+ 64, ts_mask_avail, 64, ts_mask, 64, map);
+ return -EINVAL;
+ }
+
+ bitmap_to_arr32(array32, map, 64);
+ if (array32[1]) {
+ dev_err(qmc_hdlc->dev, "Slot map out of 32bit (%*pb, %*pb) -> %*pb\n",
+ 64, ts_mask_avail, 64, ts_mask, 64, map);
+ return -EINVAL;
+ }
+
+ *slot_map = array32[0];
+ 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);
@@ -332,13 +472,14 @@ 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;
@@ -368,6 +509,15 @@ 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


2024-02-22 14:24:13

by Herve Codina

[permalink] [raw]
Subject: [PATCH v4 5/5] net: wan: fsl_qmc_hdlc: Add framer support

Add framer support in the fsl_qmc_hdlc driver in order to be able to
signal carrier changes to the network stack based on the framer status
Also use this framer to provide information related to the E1/T1 line
interface on IF_GET_IFACE and configure the line interface according to
IF_IFACE_{E1,T1} information.

Signed-off-by: Herve Codina <[email protected]>
Reviewed-by: Christophe Leroy <[email protected]>
---
drivers/net/wan/fsl_qmc_hdlc.c | 239 ++++++++++++++++++++++++++++++++-
1 file changed, 235 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wan/fsl_qmc_hdlc.c b/drivers/net/wan/fsl_qmc_hdlc.c
index 1b7f1d5af273..5e80d3ce4e51 100644
--- a/drivers/net/wan/fsl_qmc_hdlc.c
+++ b/drivers/net/wan/fsl_qmc_hdlc.c
@@ -9,6 +9,7 @@

#include <linux/bitmap.h>
#include <linux/dma-mapping.h>
+#include <linux/framer/framer.h>
#include <linux/hdlc.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
@@ -28,6 +29,9 @@ struct qmc_hdlc {
struct device *dev;
struct qmc_chan *qmc_chan;
struct net_device *netdev;
+ struct framer *framer;
+ spinlock_t carrier_lock; /* Protect carrier detection */
+ struct notifier_block nb;
bool is_crc32;
spinlock_t tx_lock; /* Protect tx descriptors */
struct qmc_hdlc_desc tx_descs[8];
@@ -41,6 +45,195 @@ static struct qmc_hdlc *netdev_to_qmc_hdlc(struct net_device *netdev)
return dev_to_hdlc(netdev)->priv;
}

+static int qmc_hdlc_framer_set_carrier(struct qmc_hdlc *qmc_hdlc)
+{
+ struct framer_status framer_status;
+ unsigned long flags;
+ int ret;
+
+ if (!qmc_hdlc->framer)
+ return 0;
+
+ spin_lock_irqsave(&qmc_hdlc->carrier_lock, flags);
+
+ ret = framer_get_status(qmc_hdlc->framer, &framer_status);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "get framer status failed (%d)\n", ret);
+ goto end;
+ }
+ if (framer_status.link_is_on)
+ netif_carrier_on(qmc_hdlc->netdev);
+ else
+ netif_carrier_off(qmc_hdlc->netdev);
+
+end:
+ spin_unlock_irqrestore(&qmc_hdlc->carrier_lock, flags);
+ return ret;
+}
+
+static int qmc_hdlc_framer_notifier(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ struct qmc_hdlc *qmc_hdlc = container_of(nb, struct qmc_hdlc, nb);
+ int ret;
+
+ if (action != FRAMER_EVENT_STATUS)
+ return NOTIFY_DONE;
+
+ ret = qmc_hdlc_framer_set_carrier(qmc_hdlc);
+ return ret ? NOTIFY_DONE : NOTIFY_OK;
+}
+
+static int qmc_hdlc_framer_start(struct qmc_hdlc *qmc_hdlc)
+{
+ struct framer_status framer_status;
+ int ret;
+
+ if (!qmc_hdlc->framer)
+ return 0;
+
+ ret = framer_power_on(qmc_hdlc->framer);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "framer power-on failed (%d)\n", ret);
+ return ret;
+ }
+
+ /* Be sure that get_status is supported */
+ ret = framer_get_status(qmc_hdlc->framer, &framer_status);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "get framer status failed (%d)\n", ret);
+ goto framer_power_off;
+ }
+
+ qmc_hdlc->nb.notifier_call = qmc_hdlc_framer_notifier;
+ ret = framer_notifier_register(qmc_hdlc->framer, &qmc_hdlc->nb);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "framer notifier register failed (%d)\n", ret);
+ goto framer_power_off;
+ }
+
+ return 0;
+
+framer_power_off:
+ framer_power_off(qmc_hdlc->framer);
+ return ret;
+}
+
+static void qmc_hdlc_framer_stop(struct qmc_hdlc *qmc_hdlc)
+{
+ if (!qmc_hdlc->framer)
+ return;
+
+ framer_notifier_unregister(qmc_hdlc->framer, &qmc_hdlc->nb);
+ framer_power_off(qmc_hdlc->framer);
+}
+
+static int qmc_hdlc_framer_set_iface(struct qmc_hdlc *qmc_hdlc, int if_iface,
+ const te1_settings *te1)
+{
+ struct framer_config config;
+ int ret;
+
+ if (!qmc_hdlc->framer)
+ return 0;
+
+ ret = framer_get_config(qmc_hdlc->framer, &config);
+ if (ret)
+ return ret;
+
+ switch (if_iface) {
+ case IF_IFACE_E1:
+ config.iface = FRAMER_IFACE_E1;
+ break;
+ case IF_IFACE_T1:
+ config.iface = FRAMER_IFACE_T1;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ switch (te1->clock_type) {
+ case CLOCK_DEFAULT:
+ /* Keep current value */
+ break;
+ case CLOCK_EXT:
+ config.clock_type = FRAMER_CLOCK_EXT;
+ break;
+ case CLOCK_INT:
+ config.clock_type = FRAMER_CLOCK_INT;
+ break;
+ default:
+ return -EINVAL;
+ }
+ config.line_clock_rate = te1->clock_rate;
+
+ return framer_set_config(qmc_hdlc->framer, &config);
+}
+
+static int qmc_hdlc_framer_get_iface(struct qmc_hdlc *qmc_hdlc, int *if_iface, te1_settings *te1)
+{
+ struct framer_config config;
+ int ret;
+
+ if (!qmc_hdlc->framer) {
+ *if_iface = IF_IFACE_E1;
+ return 0;
+ }
+
+ ret = framer_get_config(qmc_hdlc->framer, &config);
+ if (ret)
+ return ret;
+
+ switch (config.iface) {
+ case FRAMER_IFACE_E1:
+ *if_iface = IF_IFACE_E1;
+ break;
+ case FRAMER_IFACE_T1:
+ *if_iface = IF_IFACE_T1;
+ break;
+ }
+
+ if (!te1)
+ return 0; /* Only iface type requested */
+
+ switch (config.clock_type) {
+ case FRAMER_CLOCK_EXT:
+ te1->clock_type = CLOCK_EXT;
+ break;
+ case FRAMER_CLOCK_INT:
+ te1->clock_type = CLOCK_INT;
+ break;
+ default:
+ return -EINVAL;
+ }
+ te1->clock_rate = config.line_clock_rate;
+ return 0;
+}
+
+static int qmc_hdlc_framer_init(struct qmc_hdlc *qmc_hdlc)
+{
+ int ret;
+
+ if (!qmc_hdlc->framer)
+ return 0;
+
+ ret = framer_init(qmc_hdlc->framer);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "framer init failed (%d)\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void qmc_hdlc_framer_exit(struct qmc_hdlc *qmc_hdlc)
+{
+ if (!qmc_hdlc->framer)
+ return;
+
+ framer_exit(qmc_hdlc->framer);
+}
+
static int qmc_hdlc_recv_queue(struct qmc_hdlc *qmc_hdlc, struct qmc_hdlc_desc *desc, size_t size);

#define QMC_HDLC_RX_ERROR_FLAGS (QMC_RX_FLAG_HDLC_OVF | \
@@ -300,6 +493,12 @@ static int qmc_hdlc_set_iface(struct qmc_hdlc *qmc_hdlc, int if_iface, const te1

qmc_hdlc->slot_map = te1->slot_map;

+ ret = qmc_hdlc_framer_set_iface(qmc_hdlc, if_iface, te1);
+ if (ret) {
+ dev_err(qmc_hdlc->dev, "framer set iface failed %d\n", ret);
+ return ret;
+ }
+
return 0;
}

@@ -307,11 +506,16 @@ 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;
+ int ret;

switch (ifs->type) {
case IF_GET_IFACE:
- ifs->type = IF_IFACE_E1;
if (ifs->size < sizeof(te1)) {
+ /* Retrieve type only */
+ ret = qmc_hdlc_framer_get_iface(qmc_hdlc, &ifs->type, NULL);
+ if (ret)
+ return ret;
+
if (!ifs->size)
return 0; /* only type requested */

@@ -321,6 +525,11 @@ static int qmc_hdlc_ioctl(struct net_device *netdev, struct if_settings *ifs)

memset(&te1, 0, sizeof(te1));

+ /* Retrieve info from framer */
+ ret = qmc_hdlc_framer_get_iface(qmc_hdlc, &ifs->type, &te1);
+ if (ret)
+ return ret;
+
/* Update slot_map */
te1.slot_map = qmc_hdlc->slot_map;

@@ -354,10 +563,17 @@ static int qmc_hdlc_open(struct net_device *netdev)
int ret;
int i;

- ret = hdlc_open(netdev);
+ ret = qmc_hdlc_framer_start(qmc_hdlc);
if (ret)
return ret;

+ ret = hdlc_open(netdev);
+ if (ret)
+ goto framer_stop;
+
+ /* Update carrier */
+ qmc_hdlc_framer_set_carrier(qmc_hdlc);
+
chan_param.mode = QMC_HDLC;
/* HDLC_MAX_MRU + 4 for the CRC
* HDLC_MAX_MRU + 4 + 8 for the CRC and some extraspace needed by the QMC
@@ -407,6 +623,8 @@ static int qmc_hdlc_open(struct net_device *netdev)
}
hdlc_close:
hdlc_close(netdev);
+framer_stop:
+ qmc_hdlc_framer_stop(qmc_hdlc);
return ret;
}

@@ -442,6 +660,7 @@ static int qmc_hdlc_close(struct net_device *netdev)
}

hdlc_close(netdev);
+ qmc_hdlc_framer_stop(qmc_hdlc);
return 0;
}

@@ -490,6 +709,7 @@ static int qmc_hdlc_probe(struct platform_device *pdev)

qmc_hdlc->dev = &pdev->dev;
spin_lock_init(&qmc_hdlc->tx_lock);
+ spin_lock_init(&qmc_hdlc->carrier_lock);

qmc_hdlc->qmc_chan = devm_qmc_chan_get_bychild(qmc_hdlc->dev, np);
if (IS_ERR(qmc_hdlc->qmc_chan)) {
@@ -518,10 +738,19 @@ static int qmc_hdlc_probe(struct platform_device *pdev)
if (ret)
return ret;

+ qmc_hdlc->framer = devm_framer_optional_get(qmc_hdlc->dev, "fsl,framer");
+ if (IS_ERR(qmc_hdlc->framer))
+ return PTR_ERR(qmc_hdlc->framer);
+
+ ret = qmc_hdlc_framer_init(qmc_hdlc);
+ 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");
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto framer_exit;
}

hdlc = dev_to_hdlc(qmc_hdlc->netdev);
@@ -537,11 +766,12 @@ static int qmc_hdlc_probe(struct platform_device *pdev)
}

platform_set_drvdata(pdev, qmc_hdlc);
-
return 0;

free_netdev:
free_netdev(qmc_hdlc->netdev);
+framer_exit:
+ qmc_hdlc_framer_exit(qmc_hdlc);
return ret;
}

@@ -551,6 +781,7 @@ static int qmc_hdlc_remove(struct platform_device *pdev)

unregister_hdlc_device(qmc_hdlc->netdev);
free_netdev(qmc_hdlc->netdev);
+ qmc_hdlc_framer_exit(qmc_hdlc);

return 0;
}
--
2.43.0


2024-02-22 15:29:28

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 1/5] net: wan: Add support for QMC HDLC

On Thu, Feb 22, 2024 at 03:22:14PM +0100, Herve Codina wrote:
> The QMC HDLC driver provides support for HDLC using the QMC (QUICC
> Multichannel Controller) to transfer the HDLC data.

..

> +struct qmc_hdlc {
> + struct device *dev;
> + struct qmc_chan *qmc_chan;
> + struct net_device *netdev;
> + bool is_crc32;
> + spinlock_t tx_lock; /* Protect tx descriptors */

Just wondering if above tx/rx descriptors should be aligned on a cacheline
for DMA?

> + struct qmc_hdlc_desc tx_descs[8];
> + unsigned int tx_out;
> + struct qmc_hdlc_desc rx_descs[4];
> +};

..

> +#define QMC_HDLC_RX_ERROR_FLAGS (QMC_RX_FLAG_HDLC_OVF | \
> + QMC_RX_FLAG_HDLC_UNA | \
> + QMC_RX_FLAG_HDLC_ABORT | \
> + QMC_RX_FLAG_HDLC_CRC)

Wouldn't be slightly better to have it as

#define QMC_HDLC_RX_ERROR_FLAGS \
(QMC_RX_FLAG_HDLC_OVF | QMC_RX_FLAG_HDLC_UNA | \
QMC_RX_FLAG_HDLC_CRC | QMC_RX_FLAG_HDLC_ABORT)

?

..

> + ret = qmc_chan_write_submit(qmc_hdlc->qmc_chan, desc->dma_addr, desc->dma_size,
> + qmc_hdlc_xmit_complete, desc);
> + if (ret) {

> + dev_err(qmc_hdlc->dev, "qmc chan write returns %d\n", ret);
> + dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_TO_DEVICE);
> + return ret;

I would do other way around, i.e. release resource followed up by printing
a message. Printing a message is a slow operation and may prevent the (soon
freed) resources to be re-used earlier.

> + }

..

> + spin_lock_irqsave(&qmc_hdlc->tx_lock, flags);

Why not using cleanup.h from day 1?

> +end:

This label, in particular, will not be needed with above in place.

> + spin_unlock_irqrestore(&qmc_hdlc->tx_lock, flags);
> + return ret;
> +}

..

> + /* Queue as many recv descriptors as possible */
> + for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) {
> + desc = &qmc_hdlc->rx_descs[i];
> +
> + desc->netdev = netdev;
> + ret = qmc_hdlc_recv_queue(qmc_hdlc, desc, chan_param.hdlc.max_rx_buf_size);

> + if (ret) {
> + if (ret == -EBUSY && i != 0)
> + break; /* We use all the QMC chan capability */
> + goto free_desc;
> + }

Can be unfolded to

if (ret == -EBUSY && i)
break; /* We use all the QMC chan capability */
if (ret)
goto free_desc;

Easy to read and understand.

> + }

..

> +static int qmc_hdlc_probe(struct platform_device *pdev)
> +{

With

struct device *dev = &pdev->dev;

the below code will be neater (see other comments for the examples).

> + struct device_node *np = pdev->dev.of_node;

It is used only once, drop it (see below).

> + struct qmc_hdlc *qmc_hdlc;
> + struct qmc_chan_info info;
> + hdlc_device *hdlc;
> + int ret;
> +
> + qmc_hdlc = devm_kzalloc(&pdev->dev, sizeof(*qmc_hdlc), GFP_KERNEL);
> + if (!qmc_hdlc)
> + return -ENOMEM;
> +
> + qmc_hdlc->dev = &pdev->dev;
> + spin_lock_init(&qmc_hdlc->tx_lock);
> +
> + qmc_hdlc->qmc_chan = devm_qmc_chan_get_bychild(qmc_hdlc->dev, np);

qmc_hdlc->qmc_chan = devm_qmc_chan_get_bychild(dev, dev->of_node);

> + if (IS_ERR(qmc_hdlc->qmc_chan)) {
> + ret = PTR_ERR(qmc_hdlc->qmc_chan);
> + return dev_err_probe(qmc_hdlc->dev, ret, "get QMC channel failed\n");

return dev_err_probe(dev, PTR_ERR(qmc_hdlc->qmc_chan), "get QMC channel failed\n");

> + }
> +
> + ret = qmc_chan_get_info(qmc_hdlc->qmc_chan, &info);
> + if (ret) {

> + dev_err(qmc_hdlc->dev, "get QMC channel info failed %d\n", ret);
> + return ret;

Why not using same message pattern everywhere, i.e. dev_err_probe()?

return dev_err_probe(dev, ret, "get QMC channel info failed\n");

(and so on...)

> + }
> +
> + if (info.mode != QMC_HDLC) {
> + dev_err(qmc_hdlc->dev, "QMC chan mode %d is not QMC_HDLC\n",
> + info.mode);
> + return -EINVAL;
> + }
> +
> + qmc_hdlc->netdev = alloc_hdlcdev(qmc_hdlc);
> + if (!qmc_hdlc->netdev) {

> + dev_err(qmc_hdlc->dev, "failed to alloc hdlc dev\n");
> + return -ENOMEM;

We do not issue a message for -ENOMEM.

> + }
> +
> + hdlc = dev_to_hdlc(qmc_hdlc->netdev);
> + hdlc->attach = qmc_hdlc_attach;
> + hdlc->xmit = qmc_hdlc_xmit;
> + SET_NETDEV_DEV(qmc_hdlc->netdev, qmc_hdlc->dev);
> + qmc_hdlc->netdev->tx_queue_len = ARRAY_SIZE(qmc_hdlc->tx_descs);
> + qmc_hdlc->netdev->netdev_ops = &qmc_hdlc_netdev_ops;
> + ret = register_hdlc_device(qmc_hdlc->netdev);
> + if (ret) {
> + dev_err(qmc_hdlc->dev, "failed to register hdlc device (%d)\n", ret);
> + goto free_netdev;
> + }
> +
> + platform_set_drvdata(pdev, qmc_hdlc);
> +
> + return 0;
> +
> +free_netdev:
> + free_netdev(qmc_hdlc->netdev);
> + return ret;
> +}


--
With Best Regards,
Andy Shevchenko



2024-02-22 15:41:09

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 3/5] lib/bitmap: Introduce bitmap_scatter() and bitmap_gather() helpers

On Thu, Feb 22, 2024 at 03:22:16PM +0100, Herve Codina wrote:
> From: Andy Shevchenko <[email protected]>
>
> These helpers scatters or gathers a bitmap with the help of the mask
> position bits parameter.
>
> bitmap_scatter() does the following:
> src: 0000000001011010
> ||||||
> +------+|||||
> | +----+||||
> | |+----+|||
> | || +-+||
> | || | ||
> mask: ...v..vv...v..vv
> ...0..11...0..10
> dst: 0000001100000010
>
> and bitmap_gather() performs this one:
> mask: ...v..vv...v..vv
> src: 0000001100000010
> ^ ^^ ^ 0
> | || | 10
> | || > 010
> | |+--> 1010
> | +--> 11010
> +----> 011010
> dst: 0000000000011010
>
> bitmap_gather() can the seen as the reverse bitmap_scatter() operation.

> The original work was done by Andy Shevchenko.

Mine SoB is enough for a credit, but thank you :-)

..

> +/**
> + * bitmap_gather - Gather a bitmap according to given mask
> + * @dst: gathered bitmap
> + * @src: scattered bitmap
> + * @mask: mask representing bits to extract from in the scattered bitmap
> + * @nbits: number of bits in each of these bitmaps
> + *
> + * Gathers bitmap with sparse bits according to the given @mask.
> + *
> + * Example:
> + * If @src bitmap = 0x0302, with @mask = 0x1313, @dst will be 0x001a.
> + *
> + * Or in binary form
> + * @src @mask @dst
> + * 0000001100000010 0001001100010011 0000000000011010
> + *
> + * (Bits 0, 1, 4, 8, 9, 12 are copied to the bits 0, 1, 2, 3, 4, 5)
> + *
> + * A more 'visual' description of the operation:
> + * mask: ...v..vv...v..vv
> + * src: 0000001100000010
> + * ^ ^^ ^ 0
> + * | || | 10
> + * | || > 010
> + * | |+--> 1010
> + * | +--> 11010
> + * +----> 011010
> + * dst: 0000000000011010

Cool!

> + * A relationship exists between bitmap_gather() and bitmap_scatter() (See

Either '... (see'
or '(). See'

> + * bitmap_scatter() for the bitmap scatter detailed operations).

> + * Suppose scattered computed using bitmap_scatter(scattered, src, mask, n).
> + * The operation bitmap_gather(result, scattered, mask, n) leads to a result
> + * equal or equivalent to src.

This paragraph...

> + * The result can be 'equivalent' because bitmap_scatter() and bitmap_gather()
> + * are not bijective.


> + * The result and src values are equivalent in that sense that a call to
> + * bitmap_scatter(res, src, mask, n) and a call to bitmap_scatter(res, result,
> + * mask, n) will lead to the same res value.

..seems duplicating this one.

I would drop the latter one.

> + */

--
With Best Regards,
Andy Shevchenko



2024-02-22 15:41:49

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 3/5] lib/bitmap: Introduce bitmap_scatter() and bitmap_gather() helpers

On Thu, Feb 22, 2024 at 05:39:27PM +0200, Andy Shevchenko wrote:
> On Thu, Feb 22, 2024 at 03:22:16PM +0100, Herve Codina wrote:
> > From: Andy Shevchenko <[email protected]>

> > The original work was done by Andy Shevchenko.
>
> Mine SoB is enough for a credit, but thank you :-)

That said, you forgot to add your Co-developed-by.

--
With Best Regards,
Andy Shevchenko



2024-02-22 15:48:06

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 4/5] net: wan: fsl_qmc_hdlc: Add runtime timeslots changes support

On Thu, Feb 22, 2024 at 03:22:17PM +0100, Herve Codina wrote:
> 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.

..

> +static int qmc_hdlc_xlate_slot_map(struct qmc_hdlc *qmc_hdlc,
> + u32 slot_map, struct qmc_chan_ts_info *ts_info)
> +{
> + DECLARE_BITMAP(ts_mask_avail, 64);
> + DECLARE_BITMAP(ts_mask, 64);
> + DECLARE_BITMAP(map, 64);

Perhaps more 1:1 naming?

DECLARE_BITMAP(rx_ts_mask_avail, 64);
DECLARE_BITMAP(tx_ts_mask, 64);
DECLARE_BITMAP(slot_map, 64);

> + /* Tx and Rx available 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;
> + }
> +
> + bitmap_from_u64(ts_mask_avail, ts_info->rx_ts_mask_avail);
> + bitmap_from_u64(map, slot_map);
> + bitmap_scatter(ts_mask, map, ts_mask_avail, 64);
> +
> + if (bitmap_weight(ts_mask, 64) != bitmap_weight(map, 64)) {
> + dev_err(qmc_hdlc->dev, "Cannot translate timeslots %*pb -> (%*pb, %*pb)\n",
> + 64, map, 64, ts_mask_avail, 64, ts_mask);


You can save a bit of code and stack:

dev_err(qmc_hdlc->dev, "Cannot translate timeslots %64pb -> (%64pb, %64pb)\n",
slot_map, rx_ts_mask_avail, tx_ts_mask);

> + return -EINVAL;
> + }
> +
> + bitmap_to_arr64(&ts_info->tx_ts_mask, ts_mask, 64);
> + ts_info->rx_ts_mask = ts_info->tx_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)

Similar comments apply as per above function.

..

> + 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;

return dev_err_probe(...);

> + }

--
With Best Regards,
Andy Shevchenko



2024-02-22 15:49:59

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 5/5] net: wan: fsl_qmc_hdlc: Add framer support

On Thu, Feb 22, 2024 at 03:22:18PM +0100, Herve Codina wrote:
> Add framer support in the fsl_qmc_hdlc driver in order to be able to
> signal carrier changes to the network stack based on the framer status
> Also use this framer to provide information related to the E1/T1 line
> interface on IF_GET_IFACE and configure the line interface according to
> IF_IFACE_{E1,T1} information.

..

> +static int qmc_hdlc_framer_set_carrier(struct qmc_hdlc *qmc_hdlc)
> +{
> + struct framer_status framer_status;
> + unsigned long flags;
> + int ret;
> +
> + if (!qmc_hdlc->framer)
> + return 0;

> + spin_lock_irqsave(&qmc_hdlc->carrier_lock, flags);

cleanup.h ?

> + ret = framer_get_status(qmc_hdlc->framer, &framer_status);
> + if (ret) {
> + dev_err(qmc_hdlc->dev, "get framer status failed (%d)\n", ret);
> + goto end;
> + }
> + if (framer_status.link_is_on)
> + netif_carrier_on(qmc_hdlc->netdev);
> + else
> + netif_carrier_off(qmc_hdlc->netdev);
> +
> +end:
> + spin_unlock_irqrestore(&qmc_hdlc->carrier_lock, flags);
> + return ret;
> +}

--
With Best Regards,
Andy Shevchenko



2024-02-22 16:46:02

by Herve Codina

[permalink] [raw]
Subject: Re: [PATCH v4 1/5] net: wan: Add support for QMC HDLC

On Thu, 22 Feb 2024 17:29:05 +0200
Andy Shevchenko <[email protected]> wrote:

> On Thu, Feb 22, 2024 at 03:22:14PM +0100, Herve Codina wrote:
> > The QMC HDLC driver provides support for HDLC using the QMC (QUICC
> > Multichannel Controller) to transfer the HDLC data.
>
> ...
>
> > +struct qmc_hdlc {
> > + struct device *dev;
> > + struct qmc_chan *qmc_chan;
> > + struct net_device *netdev;
> > + bool is_crc32;
> > + spinlock_t tx_lock; /* Protect tx descriptors */
>
> Just wondering if above tx/rx descriptors should be aligned on a cacheline
> for DMA?

These descriptors are not used by DMA.
Not sure that aligning them to a cacheline is really needed.

>
> > + struct qmc_hdlc_desc tx_descs[8];
> > + unsigned int tx_out;
> > + struct qmc_hdlc_desc rx_descs[4];
> > +};
>
> ...
>
> > +#define QMC_HDLC_RX_ERROR_FLAGS (QMC_RX_FLAG_HDLC_OVF | \
> > + QMC_RX_FLAG_HDLC_UNA | \
> > + QMC_RX_FLAG_HDLC_ABORT | \
> > + QMC_RX_FLAG_HDLC_CRC)
>
> Wouldn't be slightly better to have it as
>
> #define QMC_HDLC_RX_ERROR_FLAGS \
> (QMC_RX_FLAG_HDLC_OVF | QMC_RX_FLAG_HDLC_UNA | \
> QMC_RX_FLAG_HDLC_CRC | QMC_RX_FLAG_HDLC_ABORT)
>
> ?

Will be done in the next iteration.

>
> ...
>
> > + ret = qmc_chan_write_submit(qmc_hdlc->qmc_chan, desc->dma_addr, desc->dma_size,
> > + qmc_hdlc_xmit_complete, desc);
> > + if (ret) {
>
> > + dev_err(qmc_hdlc->dev, "qmc chan write returns %d\n", ret);
> > + dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_TO_DEVICE);
> > + return ret;
>
> I would do other way around, i.e. release resource followed up by printing
> a message. Printing a message is a slow operation and may prevent the (soon
> freed) resources to be re-used earlier.

Will do that in the next iteration.

>
> > + }
>
> ...
>
> > + spin_lock_irqsave(&qmc_hdlc->tx_lock, flags);
>
> Why not using cleanup.h from day 1?

I don't know about cleanup.h.
Can you tell me more ?
How should I use it ?

>
> > +end:
>
> This label, in particular, will not be needed with above in place.
>
> > + spin_unlock_irqrestore(&qmc_hdlc->tx_lock, flags);
> > + return ret;
> > +}
>
> ...
>
> > + /* Queue as many recv descriptors as possible */
> > + for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) {
> > + desc = &qmc_hdlc->rx_descs[i];
> > +
> > + desc->netdev = netdev;
> > + ret = qmc_hdlc_recv_queue(qmc_hdlc, desc, chan_param.hdlc.max_rx_buf_size);
>
> > + if (ret) {
> > + if (ret == -EBUSY && i != 0)
> > + break; /* We use all the QMC chan capability */
> > + goto free_desc;
> > + }
>
> Can be unfolded to
>
> if (ret == -EBUSY && i)
> break; /* We use all the QMC chan capability */
> if (ret)
> goto free_desc;
>
> Easy to read and understand.

Sure, will be changed.

>
> > + }
>
> ...
>
> > +static int qmc_hdlc_probe(struct platform_device *pdev)
> > +{
>
> With
>
> struct device *dev = &pdev->dev;
>
> the below code will be neater (see other comments for the examples).

Will use that.

>
> > + struct device_node *np = pdev->dev.of_node;
>
> It is used only once, drop it (see below).

Ok.

>
> > + struct qmc_hdlc *qmc_hdlc;
> > + struct qmc_chan_info info;
> > + hdlc_device *hdlc;
> > + int ret;
> > +
> > + qmc_hdlc = devm_kzalloc(&pdev->dev, sizeof(*qmc_hdlc), GFP_KERNEL);
> > + if (!qmc_hdlc)
> > + return -ENOMEM;
> > +
> > + qmc_hdlc->dev = &pdev->dev;
> > + spin_lock_init(&qmc_hdlc->tx_lock);
> > +
> > + qmc_hdlc->qmc_chan = devm_qmc_chan_get_bychild(qmc_hdlc->dev, np);
>
> qmc_hdlc->qmc_chan = devm_qmc_chan_get_bychild(dev, dev->of_node);
>
> > + if (IS_ERR(qmc_hdlc->qmc_chan)) {
> > + ret = PTR_ERR(qmc_hdlc->qmc_chan);
> > + return dev_err_probe(qmc_hdlc->dev, ret, "get QMC channel failed\n");
>
> return dev_err_probe(dev, PTR_ERR(qmc_hdlc->qmc_chan), "get QMC channel failed\n");
>
> > + }
> > +
> > + ret = qmc_chan_get_info(qmc_hdlc->qmc_chan, &info);
> > + if (ret) {
>
> > + dev_err(qmc_hdlc->dev, "get QMC channel info failed %d\n", ret);
> > + return ret;
>
> Why not using same message pattern everywhere, i.e. dev_err_probe()?
>
> return dev_err_probe(dev, ret, "get QMC channel info failed\n");
>
> (and so on...)

No reason. Just because I missed them.
Will be updated using dev_err_probe().

>
> > + }
> > +
> > + if (info.mode != QMC_HDLC) {
> > + dev_err(qmc_hdlc->dev, "QMC chan mode %d is not QMC_HDLC\n",
> > + info.mode);
> > + return -EINVAL;
> > + }
> > +
> > + qmc_hdlc->netdev = alloc_hdlcdev(qmc_hdlc);
> > + if (!qmc_hdlc->netdev) {
>
> > + dev_err(qmc_hdlc->dev, "failed to alloc hdlc dev\n");
> > + return -ENOMEM;
>
> We do not issue a message for -ENOMEM.

And I know :(
Will be updated.

>
> > + }
> > +
> > + hdlc = dev_to_hdlc(qmc_hdlc->netdev);
> > + hdlc->attach = qmc_hdlc_attach;
> > + hdlc->xmit = qmc_hdlc_xmit;
> > + SET_NETDEV_DEV(qmc_hdlc->netdev, qmc_hdlc->dev);
> > + qmc_hdlc->netdev->tx_queue_len = ARRAY_SIZE(qmc_hdlc->tx_descs);
> > + qmc_hdlc->netdev->netdev_ops = &qmc_hdlc_netdev_ops;
> > + ret = register_hdlc_device(qmc_hdlc->netdev);
> > + if (ret) {
> > + dev_err(qmc_hdlc->dev, "failed to register hdlc device (%d)\n", ret);
> > + goto free_netdev;
> > + }
> > +
> > + platform_set_drvdata(pdev, qmc_hdlc);
> > +
> > + return 0;
> > +
> > +free_netdev:
> > + free_netdev(qmc_hdlc->netdev);
> > + return ret;
> > +}
>
>

Thanks for the review.

Hervé

2024-02-22 16:56:49

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 1/5] net: wan: Add support for QMC HDLC

On Thu, Feb 22, 2024 at 05:45:01PM +0100, Herve Codina wrote:
> On Thu, 22 Feb 2024 17:29:05 +0200
> Andy Shevchenko <[email protected]> wrote:
> > On Thu, Feb 22, 2024 at 03:22:14PM +0100, Herve Codina wrote:

..

> > > + spin_lock_irqsave(&qmc_hdlc->tx_lock, flags);
> >
> > Why not using cleanup.h from day 1?
>
> I don't know about cleanup.h.
> Can you tell me more ?
> How should I use it ?
>
> > > +end:
> >
> > This label, in particular, will not be needed with above in place.
> >
> > > + spin_unlock_irqrestore(&qmc_hdlc->tx_lock, flags);
> > > + return ret;
> > > +}

Here are the examples:
6191e49de389 ("pinctrl: baytrail: Simplify code with cleanup helpers")
1d1b4770d4b6 ("platform/x86/intel/vsec: Use cleanup.h")
e2eeddefb046 ("pstore: inode: Convert mutex usage to guard(mutex)")

Some advanced stuff:
ced085ef369a ("PCI: Introduce cleanup helpers for device reference counts and locks")

Hope this helps.

--
With Best Regards,
Andy Shevchenko



2024-02-22 17:48:27

by Herve Codina

[permalink] [raw]
Subject: Re: [PATCH v4 1/5] net: wan: Add support for QMC HDLC

Andy, Jakub,

On Thu, 22 Feb 2024 18:56:26 +0200
Andy Shevchenko <[email protected]> wrote:

> On Thu, Feb 22, 2024 at 05:45:01PM +0100, Herve Codina wrote:
> > On Thu, 22 Feb 2024 17:29:05 +0200
> > Andy Shevchenko <[email protected]> wrote:
> > > On Thu, Feb 22, 2024 at 03:22:14PM +0100, Herve Codina wrote:
>
> ...
>
> > > > + spin_lock_irqsave(&qmc_hdlc->tx_lock, flags);
> > >
> > > Why not using cleanup.h from day 1?
> >
> > I don't know about cleanup.h.
> > Can you tell me more ?
> > How should I use it ?
> >
> > > > +end:
> > >
> > > This label, in particular, will not be needed with above in place.
> > >
> > > > + spin_unlock_irqrestore(&qmc_hdlc->tx_lock, flags);
> > > > + return ret;
> > > > +}
>
> Here are the examples:
> 6191e49de389 ("pinctrl: baytrail: Simplify code with cleanup helpers")
> 1d1b4770d4b6 ("platform/x86/intel/vsec: Use cleanup.h")
> e2eeddefb046 ("pstore: inode: Convert mutex usage to guard(mutex)")
>
> Some advanced stuff:
> ced085ef369a ("PCI: Introduce cleanup helpers for device reference counts and locks")
>
> Hope this helps.

Sure, thanks for the pointer.

Jakub,
nothing in drivers/net seems to use the guard() (from cleanup.h) family
macro.
Are you ok with having this HDLC driver that uses guard() macros ?

Best regards,
Hervé

--
Hervé Codina, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

2024-02-22 20:40:12

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 0/5] Add support for QMC HDLC

On Thu, Feb 22, 2024 at 03:22:13PM +0100, Herve Codina wrote:
> Hi,
>
> This series introduces the QMC HDLC support.
>
> Patches were previously sent as part of a full feature series and were
> previously reviewed in that context:
> "Add support for QMC HDLC, framer infrastructure and PEF2256 framer" [1]
>
> In order to ease the merge, the full feature series has been split and
> needed parts were merged in v6.8-rc1:
> - "Prepare the PowerQUICC QMC and TSA for the HDLC QMC driver" [2]
> - "Add support for framer infrastructure and PEF2256 framer" [3]
>
> This series contains patches related to the QMC HDLC part (QMC HDLC
> driver):
> - Introduce the QMC HDLC driver (patches 1 and 2)
> - Add timeslots change support in QMC HDLC (patch 3)
> - Add framer support as a framer consumer in QMC HDLC (patch 4)
>
> Compare to the original full feature series, a modification was done on
> patch 3 in order to use a coherent prefix in the commit title.
>
> I kept the patches unsquashed as they were previously sent and reviewed.
> Of course, I can squash them if needed.
>
> Compared to the previous iteration:
> https://lore.kernel.org/linux-kernel/[email protected]/
> this v4 series mainly:

From my point of view after addressing the few non-critical issues
the v4 will be final. Thank you!

--
With Best Regards,
Andy Shevchenko



2024-02-22 21:51:12

by Yury Norov

[permalink] [raw]
Subject: Re: [PATCH v4 3/5] lib/bitmap: Introduce bitmap_scatter() and bitmap_gather() helpers

On Thu, Feb 22, 2024 at 05:49:59PM +0100, Herve Codina wrote:
> Hi Andy, Yury,
>
> On Thu, 22 Feb 2024 17:39:27 +0200
> Andy Shevchenko <[email protected]> wrote:
>
> ...
> > > + * bitmap_scatter() for the bitmap scatter detailed operations).
> >
> > > + * Suppose scattered computed using bitmap_scatter(scattered, src, mask, n).
> > > + * The operation bitmap_gather(result, scattered, mask, n) leads to a result
> > > + * equal or equivalent to src.
> >
> > This paragraph...
> >
> > > + * The result can be 'equivalent' because bitmap_scatter() and bitmap_gather()
> > > + * are not bijective.
> >
> >
> > > + * The result and src values are equivalent in that sense that a call to
> > > + * bitmap_scatter(res, src, mask, n) and a call to bitmap_scatter(res, result,
> > > + * mask, n) will lead to the same res value.
> >
> > ...seems duplicating this one.
> >
> > I would drop the latter one.
>
> I would like to give details about the 'equivalent' in this scatter/gather case.

If you would like - please do! :)

> If Yury is ok, I can drop this last paragraph.

The original bitmap_onto() description is 3 times longer, and barely
that descriptive. I'm OK with your working and especially pictures.

Thanks,
Yury

2024-02-23 10:08:18

by Herve Codina

[permalink] [raw]
Subject: Re: [PATCH v4 3/5] lib/bitmap: Introduce bitmap_scatter() and bitmap_gather() helpers

Andy, Yury,

On Thu, 22 Feb 2024 13:50:48 -0800
Yury Norov <[email protected]> wrote:

> On Thu, Feb 22, 2024 at 05:49:59PM +0100, Herve Codina wrote:
> > Hi Andy, Yury,
> >
> > On Thu, 22 Feb 2024 17:39:27 +0200
> > Andy Shevchenko <[email protected]> wrote:
> >
> > ...
> > > > + * bitmap_scatter() for the bitmap scatter detailed operations).
> > >
> > > > + * Suppose scattered computed using bitmap_scatter(scattered, src, mask, n).
> > > > + * The operation bitmap_gather(result, scattered, mask, n) leads to a result
> > > > + * equal or equivalent to src.
> > >
> > > This paragraph...
> > >
> > > > + * The result can be 'equivalent' because bitmap_scatter() and bitmap_gather()
> > > > + * are not bijective.
> > >
> > >
> > > > + * The result and src values are equivalent in that sense that a call to
> > > > + * bitmap_scatter(res, src, mask, n) and a call to bitmap_scatter(res, result,
> > > > + * mask, n) will lead to the same res value.
> > >
> > > ...seems duplicating this one.
> > >
> > > I would drop the latter one.
> >
> > I would like to give details about the 'equivalent' in this scatter/gather case.
>
> If you would like - please do! :)
>
> > If Yury is ok, I can drop this last paragraph.
>
> The original bitmap_onto() description is 3 times longer, and barely
> that descriptive. I'm OK with your working and especially pictures.
>

Right, I will keep my last paragraph in the next iteration.

Regards,
Hervé



2024-02-29 12:56:22

by Herve Codina

[permalink] [raw]
Subject: Re: [PATCH v4 5/5] net: wan: fsl_qmc_hdlc: Add framer support

Hi Andy,

On Thu, 22 Feb 2024 17:49:40 +0200
Andy Shevchenko <[email protected]> wrote:

> On Thu, Feb 22, 2024 at 03:22:18PM +0100, Herve Codina wrote:
> > Add framer support in the fsl_qmc_hdlc driver in order to be able to
> > signal carrier changes to the network stack based on the framer status
> > Also use this framer to provide information related to the E1/T1 line
> > interface on IF_GET_IFACE and configure the line interface according to
> > IF_IFACE_{E1,T1} information.
>
> ...
>
> > +static int qmc_hdlc_framer_set_carrier(struct qmc_hdlc *qmc_hdlc)
> > +{
> > + struct framer_status framer_status;
> > + unsigned long flags;
> > + int ret;
> > +
> > + if (!qmc_hdlc->framer)
> > + return 0;
>
> > + spin_lock_irqsave(&qmc_hdlc->carrier_lock, flags);
>
> cleanup.h ?
>
> > + ret = framer_get_status(qmc_hdlc->framer, &framer_status);
> > + if (ret) {
> > + dev_err(qmc_hdlc->dev, "get framer status failed (%d)\n", ret);
> > + goto end;
> > + }
> > + if (framer_status.link_is_on)
> > + netif_carrier_on(qmc_hdlc->netdev);
> > + else
> > + netif_carrier_off(qmc_hdlc->netdev);
> > +
> > +end:
> > + spin_unlock_irqrestore(&qmc_hdlc->carrier_lock, flags);
> > + return ret;
> > +}
>

I've got an issue with guard(spinlock_irqsave).

I changed this code to:
--- 8< ---
static int qmc_hdlc_framer_set_carrier(struct qmc_hdlc *qmc_hdlc)
{
struct framer_status framer_status;
int ret;

if (!qmc_hdlc->framer)
return 0;

guard(spinlock_irqsave)(&qmc_hdlc->carrier_lock);

ret = framer_get_status(qmc_hdlc->framer, &framer_status);
if (ret) {
dev_err(qmc_hdlc->dev, "get framer status failed (%d)\n", ret);
return ret;
}
if (framer_status.link_is_on)
netif_carrier_on(qmc_hdlc->netdev);
else
netif_carrier_off(qmc_hdlc->netdev);

return 0;
}
--- 8< ---

I have the following warning (make C=1):
drivers/net/wan/fsl_qmc_hdlc.c:49:12: warning: context imbalance in 'qmc_hdlc_framer_set_carrier' - wrong count at exit

I also tried to call guard(spinlock_irqsave) before 'if (!qmc_hdlc->framer)'
but it does not change anything.

Did I miss something in the guard(spinlock_irqsave) usage ?

Best regards,
Hervé

2024-02-29 13:58:27

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v4 5/5] net: wan: fsl_qmc_hdlc: Add framer support

On Thu, Feb 29, 2024 at 01:56:05PM +0100, Herve Codina wrote:
> On Thu, 22 Feb 2024 17:49:40 +0200
> Andy Shevchenko <[email protected]> wrote:
> > On Thu, Feb 22, 2024 at 03:22:18PM +0100, Herve Codina wrote:

..

> I've got an issue with guard(spinlock_irqsave).

No, you got an issue with sparse.

> I have the following warning (make C=1):
> drivers/net/wan/fsl_qmc_hdlc.c:49:12: warning: context imbalance in 'qmc_hdlc_framer_set_carrier' - wrong count at exit
>
> I also tried to call guard(spinlock_irqsave) before 'if (!qmc_hdlc->framer)'
> but it does not change anything.
>
> Did I miss something in the guard(spinlock_irqsave) usage ?

You may ignore that for now. Not your problem, no problem in the code.

https://lore.kernel.org/linux-sparse/[email protected]/

--
With Best Regards,
Andy Shevchenko



2024-02-29 14:16:01

by Herve Codina

[permalink] [raw]
Subject: Re: [PATCH v4 5/5] net: wan: fsl_qmc_hdlc: Add framer support

On Thu, 29 Feb 2024 15:58:06 +0200
Andy Shevchenko <[email protected]> wrote:

> On Thu, Feb 29, 2024 at 01:56:05PM +0100, Herve Codina wrote:
> > On Thu, 22 Feb 2024 17:49:40 +0200
> > Andy Shevchenko <[email protected]> wrote:
> > > On Thu, Feb 22, 2024 at 03:22:18PM +0100, Herve Codina wrote:
>
> ...
>
> > I've got an issue with guard(spinlock_irqsave).
>
> No, you got an issue with sparse.
>
> > I have the following warning (make C=1):
> > drivers/net/wan/fsl_qmc_hdlc.c:49:12: warning: context imbalance in 'qmc_hdlc_framer_set_carrier' - wrong count at exit
> >
> > I also tried to call guard(spinlock_irqsave) before 'if (!qmc_hdlc->framer)'
> > but it does not change anything.
> >
> > Did I miss something in the guard(spinlock_irqsave) usage ?
>
> You may ignore that for now. Not your problem, no problem in the code.
>
> https://lore.kernel.org/linux-sparse/[email protected]/
>

Perfect, thanks.

Hervé