[V10,net-next,01/10] net: hibmcge: Add pci table supported in this module

Commit Message

Jijie Shao Sept. 12, 2024, 2:51 a.m. UTC

Add pci table supported in this module, and implement pci_driver function
to initialize this driver.

hibmcge is a passthrough network device. Its software runs
on the host side, and the MAC hardware runs on the BMC side
to reduce the host CPU area. The software interacts with the
MAC hardware through the PCIe.

  ┌─────────────────────────┐
  │ HOST CPU network device │
  │    ┌──────────────┐     │
  │    │hibmcge driver│     │
  │    └─────┬─┬──────┘     │
  │          │ │            │
  │HOST  ┌───┴─┴───┐        │
  │      │ PCIE RC │        │
  └──────┴───┬─┬───┴────────┘
             │ │
            PCIE
             │ │
  ┌──────┬───┴─┴───┬────────┐
  │      │ PCIE EP │        │
  │BMC   └───┬─┬───┘        │
  │          │ │            │
  │ ┌────────┴─┴──────────┐ │
  │ │        GE           │ │
  │ │ ┌─────┐    ┌─────┐  │ │
  │ │ │ MAC │    │ MAC │  │ │
  └─┴─┼─────┼────┼─────┼──┴─┘
      │ PHY │    │ PHY │
      └─────┘    └─────┘

Signed-off-by: Jijie Shao <[e-mail]>
---
ChangeLog:
v7 -> v8:
  - Set netdev->pcpu_stat_type to NETDEV_PCPU_STAT_TSTATS, suggested by Jakub
  v7: https://lore.kernel.org/all/[e-mail]/
v6 -> v7:
  - Add devm_netdev_alloc_pcpu_stats() to init netdev->tstats,
    suggested by Paolo.
  v6: https://lore.kernel.org/all/[e-mail]/
RFC v1 -> RFC v2:
  - Add the null pointer check on the return value of pcim_iomap_table(),
    suggested by Jonathan.
  RFC v1: https://lore.kernel.org/all/[e-mail]/
---
 .../ethernet/hisilicon/hibmcge/hbg_common.h   | 16 ++++
 .../net/ethernet/hisilicon/hibmcge/hbg_main.c | 89 +++++++++++++++++++
 2 files changed, 105 insertions(+)
 create mode 100644 drivers/net/ethernet/hisilicon/hibmcge/hbg_common.h
 create mode 100644 drivers/net/ethernet/hisilicon/hibmcge/hbg_main.c

Comments

Jakub Kicinski Sept. 15, 2024, 3:10 p.m. UTC | #1

On Thu, 12 Sep 2024 10:51:18 +0800 Jijie Shao wrote:
> +	netdev->tstats = devm_netdev_alloc_pcpu_stats(&pdev->dev,
> +						      struct pcpu_sw_netstats);
> +	if (!netdev->tstats)
> +		return -ENOMEM;
> +	netdev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;

take a look at how pcpu_stat_type is used in net/core/dev.c
core will automatically allocate the stats for you and handle them in
the ndo for reading stats
your current code repeats what core already does so it will leak the
memory and I think double count

Patch

diff --git a/drivers/net/ethernet/hisilicon/hibmcge/hbg_common.h b/drivers/net/ethernet/hisilicon/hibmcge/hbg_common.h
new file mode 100644
index 000000000000..614650e9a71f
--- /dev/null
+++ b/drivers/net/ethernet/hisilicon/hibmcge/hbg_common.h
@@ -0,0 +1,16 @@ 
+/* SPDX-License-Identifier: GPL-2.0+ */
+/* Copyright (c) 2024 Hisilicon Limited. */
+
+#ifndef __HBG_COMMON_H
+#define __HBG_COMMON_H
+
+#include <linux/netdevice.h>
+#include <linux/pci.h>
+
+struct hbg_priv {
+	struct net_device *netdev;
+	struct pci_dev *pdev;
+	u8 __iomem *io_base;
+};
+
+#endif
diff --git a/drivers/net/ethernet/hisilicon/hibmcge/hbg_main.c b/drivers/net/ethernet/hisilicon/hibmcge/hbg_main.c
new file mode 100644
index 000000000000..30e29362346b
--- /dev/null
+++ b/drivers/net/ethernet/hisilicon/hibmcge/hbg_main.c
@@ -0,0 +1,89 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2024 Hisilicon Limited.
+
+#include <linux/etherdevice.h>
+#include <linux/netdevice.h>
+#include <linux/pci.h>
+#include "hbg_common.h"
+
+static int hbg_pci_init(struct pci_dev *pdev)
+{
+	struct net_device *netdev = pci_get_drvdata(pdev);
+	struct hbg_priv *priv = netdev_priv(netdev);
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	ret = pcim_enable_device(pdev);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to enable PCI device\n");
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to set PCI DMA mask\n");
+
+	ret = pcim_iomap_regions(pdev, BIT(0), dev_driver_string(dev));
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to map PCI bar space\n");
+
+	priv->io_base = pcim_iomap_table(pdev)[0];
+	if (!priv->io_base)
+		return dev_err_probe(dev, -ENOMEM, "failed to get io base\n");
+
+	pci_set_master(pdev);
+	return 0;
+}
+
+static int hbg_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	struct device *dev = &pdev->dev;
+	struct net_device *netdev;
+	struct hbg_priv *priv;
+	int ret;
+
+	netdev = devm_alloc_etherdev_mqs(dev, sizeof(struct hbg_priv), 1, 1);
+	if (!netdev)
+		return -ENOMEM;
+
+	pci_set_drvdata(pdev, netdev);
+
+	SET_NETDEV_DEV(netdev, dev);
+
+	priv = netdev_priv(netdev);
+	priv->netdev = netdev;
+	priv->pdev = pdev;
+
+	netdev->tstats = devm_netdev_alloc_pcpu_stats(&pdev->dev,
+						      struct pcpu_sw_netstats);
+	if (!netdev->tstats)
+		return -ENOMEM;
+	netdev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
+
+	ret = hbg_pci_init(pdev);
+	if (ret)
+		return ret;
+
+	ret = devm_register_netdev(dev, netdev);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to register netdev\n");
+
+	netif_carrier_off(netdev);
+	return 0;
+}
+
+static const struct pci_device_id hbg_pci_tbl[] = {
+	{PCI_VDEVICE(HUAWEI, 0x3730), 0},
+	{ }
+};
+MODULE_DEVICE_TABLE(pci, hbg_pci_tbl);
+
+static struct pci_driver hbg_driver = {
+	.name		= "hibmcge",
+	.id_table	= hbg_pci_tbl,
+	.probe		= hbg_probe,
+};
+module_pci_driver(hbg_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Huawei Tech. Co., Ltd.");
+MODULE_DESCRIPTION("hibmcge driver");
+MODULE_VERSION("1.0");