From: "Neftin, Sasha" <sasha.neftin@intel.com>
To: Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
Jesse Brandeburg <jesse.brandeburg@intel.com>,
Tony Nguyen <anthony.l.nguyen@intel.com>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>
Cc: <netdev@vger.kernel.org>, <kernel-janitors@vger.kernel.org>,
<linux-kernel@vger.kernel.org>,
<intel-wired-lan@lists.osuosl.org>,
Christoph Hellwig <hch@lst.de>,
"Neftin, Sasha" <sasha.neftin@intel.com>,
"Avivi, Amir" <amir.avivi@intel.com>
Subject: Re: [Intel-wired-lan] [PATCH] e1000e: Remove useless DMA-32 fallback configuration
Date: Fri, 28 Jan 2022 12:19:44 +0200 [thread overview]
Message-ID: <6fb7df68-9772-0552-344c-27a12ac00b0a@intel.com> (raw)
In-Reply-To: <5549ec8837b3a6fab83e92c5206cc100ffd23d85.1641752508.git.christophe.jaillet@wanadoo.fr>
On 1/9/2022 20:23, Christophe JAILLET wrote:
> As stated in [1], dma_set_mask() with a 64-bit mask never fails if
> dev->dma_mask is non-NULL.
> So, if it fails, the 32 bits case will also fail for the same reason.
>
> So, if dma_set_mask_and_coherent() succeeds, 'pci_using_dac' is known to be
> 1.
>
> Simplify code and remove some dead code accordingly.
>
> [1]: https://lkml.org/lkml/2021/6/7/398
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> ---
> drivers/net/ethernet/intel/e1000e/netdev.c | 22 +++++++---------------
> 1 file changed, 7 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
> index 635a95927e93..4f6ee5c44f75 100644
> --- a/drivers/net/ethernet/intel/e1000e/netdev.c
> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c
> @@ -7385,9 +7385,9 @@ static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> resource_size_t flash_start, flash_len;
> static int cards_found;
> u16 aspm_disable_flag = 0;
> - int bars, i, err, pci_using_dac;
> u16 eeprom_data = 0;
> u16 eeprom_apme_mask = E1000_EEPROM_APME;
> + int bars, i, err;
> s32 ret_val = 0;
>
> if (ei->flags2 & FLAG2_DISABLE_ASPM_L0S)
> @@ -7401,17 +7401,11 @@ static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> if (err)
> return err;
>
> - pci_using_dac = 0;
> err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
> - if (!err) {
> - pci_using_dac = 1;
> - } else {
> - err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> - if (err) {
> - dev_err(&pdev->dev,
> - "No usable DMA configuration, aborting\n");
> - goto err_dma;
> - }
> + if (err) {
> + dev_err(&pdev->dev,
> + "No usable DMA configuration, aborting\n");
> + goto err_dma;
> }
>
> bars = pci_select_bars(pdev, IORESOURCE_MEM);
> @@ -7547,10 +7541,8 @@ static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>
> netdev->priv_flags |= IFF_UNICAST_FLT;
>
> - if (pci_using_dac) {
> - netdev->features |= NETIF_F_HIGHDMA;
> - netdev->vlan_features |= NETIF_F_HIGHDMA;
> - }
> + netdev->features |= NETIF_F_HIGHDMA;
> + netdev->vlan_features |= NETIF_F_HIGHDMA;
>
> /* MTU range: 68 - max_hw_frame_size */
> netdev->min_mtu = ETH_MIN_MTU;
Thank you Christophe
Acked-by: Sasha Neftin <sasha.neftin@intel.com>
prev parent reply other threads:[~2022-01-28 10:20 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-09 18:23 [PATCH] e1000e: Remove useless DMA-32 fallback configuration Christophe JAILLET
2022-01-28 10:19 ` Neftin, Sasha [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6fb7df68-9772-0552-344c-27a12ac00b0a@intel.com \
--to=sasha.neftin@intel.com \
--cc=amir.avivi@intel.com \
--cc=anthony.l.nguyen@intel.com \
--cc=christophe.jaillet@wanadoo.fr \
--cc=davem@davemloft.net \
--cc=hch@lst.de \
--cc=intel-wired-lan@lists.osuosl.org \
--cc=jesse.brandeburg@intel.com \
--cc=kernel-janitors@vger.kernel.org \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).