From: "Arnd Bergmann" <arnd@arndb.de>
To: "Vamsi Attunuru" <vattunuru@marvell.com>,
"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] misc: mrvl-dpi: add octeontx3 dpi driver
Date: Wed, 14 Feb 2024 12:22:53 +0100 [thread overview]
Message-ID: <165cec24-680e-4d3e-883e-56fccbb4d7d9@app.fastmail.com> (raw)
In-Reply-To: <20240214035524.1245615-1-vattunuru@marvell.com>
On Wed, Feb 14, 2024, at 04:55, Vamsi Attunuru wrote:
> Adds PCIe PF driver for OcteonTx3 DPI PF device which initializes DPI
> DMA hardware's global configuration and enables PF-VF mbox channels
> which can be used by it's VF devices. This DPI PF driver handles only
> the resource configuration requests from VFs and it does not have any
> data movement functionality.
>
> Signed-off-by: Vamsi Attunuru <vattunuru@marvell.com>
This looks incomplete, as there is no apparent interface to
actually use the driver from either userspace or kernel. I
understand that you want to merge this one step at a time,
but please try to at least point out how this is intended
to be used, or post it together with an (in-kernel) user
if you plan to upstream that.
Is this used for anything other than networking? If not,
maybe it should be part of drivers/net/ instead of
drivers/misc.
A few more things that Greg hasn't already commented on:
> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> index 4fb291f0bf7c..3142fdb1b4c0 100644
> --- a/drivers/misc/Kconfig
> +++ b/drivers/misc/Kconfig
> @@ -574,6 +574,16 @@ config NSM
> To compile this driver as a module, choose M here.
> The module will be called nsm.
>
> +config MARVELL_OCTEONTX3_DPI
> + tristate "OcteonTX3 DPI driver"
Is OcteonTX3 an actual product name? I thought the follow-up
to OcteonTX2 (cn9[268]xx) was the OCTEON 10 line. Or is
this a follow-up to the Marvell Armada (cn91xx) line?
> +static void dpi_poll_pfvf_mbox(struct dpipf *dpi)
> +{
> + u64 reg;
> + u32 vf;
> +
> + reg = dpi_reg_read(dpi, DPI_MBOX_VF_PF_INT);
> + if (reg) {
> + for (vf = 0; vf < DPI_MAX_VFS; vf++) {
> + if (!(reg & (0x1UL << vf)))
> + continue;
> +
> + if (!dpi->mbox[vf]) {
> + dev_err(&dpi->pdev->dev, "bad mbox vf %d\n", vf);
> + continue;
> + }
> +
> + schedule_work(&dpi->mbox[vf]->wk.work);
> + }
> +
> + if (reg)
> + dpi_reg_write(dpi, DPI_MBOX_VF_PF_INT, reg);
> + }
> +}
> +
> +static irqreturn_t dpi_mbox_intr_handler(int irq, void *data)
> +{
> + struct dpipf *dpi = data;
> +
> + dpi_poll_pfvf_mbox(dpi);
> +
> + return IRQ_HANDLED;
> +}
Have you considered using the drivers/mailbox framework for
the mailbox portion?
> +static void dpi_pfvf_mbox_work(struct work_struct *work)
> +{
> + struct dpi_pfvf_mbox_wk *wk = container_of(work, struct
> dpi_pfvf_mbox_wk, work);
> + union dpi_mbox_message_t msg = { 0 };
> + struct dpi_mbox *mbox = NULL;
> + struct dpipf_vf *dpivf;
> + struct dpipf *dpi;
> + int vf_id;
> +
> + mbox = (struct dpi_mbox *)wk->ctxptr;
> + dpi = (struct dpipf *)mbox->pf;
Can these pointers be strictly typed instead of casting
from a void*?
> +static int dpi_pfvf_mbox_setup(struct dpipf *dpi)
> +{
> + int vf;
> +
> + for (vf = 0; vf < DPI_MAX_VFS; vf++) {
> + dpi->mbox[vf] = vzalloc(sizeof(*dpi->mbox[vf]));
> +
dpi->mbox[vf] does not look excessively large, so I think
kzalloc() is better than vzalloc() here.
> +module_init(dpi_init_module);
> +module_exit(dpi_cleanup_module);
> +MODULE_DEVICE_TABLE(pci, dpi_id_table);
> +MODULE_AUTHOR("Marvell International Ltd.");
> +MODULE_DESCRIPTION(DPI_DRV_STRING);
> +MODULE_LICENSE("GPL");
> +MODULE_VERSION(DPI_DRV_VERSION);
Please remove the DPI_DRV_STRING and DPI_DRV_VERSION macros,
they prevent grepping for the strings.
> diff --git a/drivers/misc/mrvl-dpi/dpi.h b/drivers/misc/mrvl-dpi/dpi.h
> new file mode 100644
> index 000000000000..99ebe6bbe577
> --- /dev/null
> +++ b/drivers/misc/mrvl-dpi/dpi.h
> @@ -0,0 +1,232 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Marvell OcteonTx3 DPI driver
> + *
> + * Copyright (C) 2024 Marvell International Ltd.
> + */
> +
> +#ifndef __DPI_H__
> +#define __DPI_H__
I see no need for a separate header file if there is no other
driver including it, so just merge this all into the .c file.
> +union dpi_mbox_message_t {
> + uint64_t u[2];
> + struct dpi_mbox_message_s {
> + /* VF ID to configure */
> + uint64_t vfid :8;
> + /* Command code */
> + uint64_t cmd :4;
> + /* Command buffer size in 8-byte words */
> + uint64_t csize :14;
> + /* aura of the command buffer */
> + uint64_t aura :20;
> + /* SSO PF function */
> + uint64_t sso_pf_func :16;
> + /* NPA PF function */
> + uint64_t npa_pf_func :16;
> + /* Work queue completion status enable */
> + uint64_t wqecs :1;
> + /* Work queue completion status byte offset */
> + uint64_t wqecsoff :7;
> + } s __packed;
> +};
Is this a hardware structure? If it is, you probably don't
want to use bit fields here, even in the best case that
is a bug that prevents you from using the driver in
big-endian mode.
I also see that there are only 86 bits defined, and one
field crosses a 64-bit boundary, which feels odd.
Arnd
next prev parent reply other threads:[~2024-02-14 11:23 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-14 3:55 [PATCH 1/1] misc: mrvl-dpi: add octeontx3 dpi driver Vamsi Attunuru
2024-02-14 10:50 ` Greg KH
2024-02-14 11:40 ` [EXT] " Vamsi Krishna Attunuru
2024-02-14 11:22 ` Arnd Bergmann [this message]
2024-02-14 13:33 ` Vamsi Krishna Attunuru
2024-02-16 10:32 ` [PATCH v2 1/1] misc: mrvl-cn10k-dpi: add Octeon CN10K " Vamsi Attunuru
2024-02-17 8:13 ` Greg KH
2024-02-19 5:03 ` [EXT] " Vamsi Krishna Attunuru
2024-02-19 6:18 ` Greg KH
2024-02-19 7:03 ` Vamsi Krishna Attunuru
2024-02-28 16:21 ` [PATCH v3 1/1] misc: mrvl-cn10k-dpi: add Octeon CN10K DPI administrative driver Vamsi Attunuru
2024-03-07 21:55 ` Greg KH
2024-03-08 11:36 ` [EXTERNAL] " Vamsi Krishna Attunuru
2024-03-12 10:56 ` [PATCH v4 " Vamsi Attunuru
2024-04-11 13:02 ` Greg KH
2024-04-12 6:34 ` [EXTERNAL] " Vamsi Krishna Attunuru
2024-04-12 12:10 ` [PATCH v5 " Vamsi Attunuru
2024-04-12 12:26 ` Greg KH
2024-04-12 13:56 ` [EXTERNAL] " Vamsi Krishna Attunuru
2024-04-12 15:34 ` Greg KH
2024-04-12 16:19 ` Vamsi Krishna Attunuru
2024-04-13 5:47 ` Greg KH
2024-04-13 10:58 ` Vamsi Krishna Attunuru
2024-04-13 11:25 ` Greg KH
2024-04-13 16:17 ` Vamsi Krishna Attunuru
2024-04-13 19:11 ` Arnd Bergmann
2024-04-14 9:33 ` Vamsi Krishna Attunuru
2024-04-14 9:46 ` Greg Kroah-Hartman
2024-04-14 12:32 ` Vamsi Krishna Attunuru
2024-04-25 13:36 ` Vamsi Krishna Attunuru
2024-04-26 1:04 ` Greg KH
2024-04-26 18:20 ` [PATCH v6 " Vamsi Attunuru
2024-04-27 11:06 ` Greg KH
2024-04-27 11:59 ` [EXTERNAL] " Vamsi Krishna Attunuru
2024-04-29 5:50 ` Vamsi Attunuru
2024-04-29 9:13 ` Greg KH
2024-05-01 7:46 ` [EXTERNAL] " Vamsi Krishna Attunuru
2024-05-01 8:02 ` Greg KH
2024-05-20 11:06 ` [PATCH v7 " Vamsi Attunuru
2024-04-30 14:00 ` [PATCH v6 " kernel test robot
2024-04-30 14:22 ` kernel test robot
2024-04-30 15:36 ` kernel test robot
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