From: Bjorn Helgaas <helgaas@kernel.org>
To: Yicong Yang <yangyicong@hisilicon.com>
Cc: linux-pci@vger.kernel.org, f.fangjian@huawei.com
Subject: Re: [PATCH 5/6] PCI: Add PCIE_LNKCAP2_SLS2SPEED macro
Date: Wed, 5 Feb 2020 12:54:46 -0600 [thread overview]
Message-ID: <20200205185446.GA231340@google.com> (raw)
In-Reply-To: <1579079063-5668-6-git-send-email-yangyicong@hisilicon.com>
On Wed, Jan 15, 2020 at 05:04:22PM +0800, Yicong Yang wrote:
> Add PCIE_LNKCAP2_SLS2SPEED macro for transforming raw link cap 2
> value to link speed. Use it in pcie_get_speed_cap() to reduce
> redundancy. We'll not touch the functions when new link
> speed comes.
The patch seems OK to me, but I don't see where it reduces redundancy.
There was one copy of "lnkcap2 & PCI_EXP_LNKCAP2_SLS_32_0GB" before,
and there's one copy after. It's just moved from pci.c to pci.h.
Or am I missing something?
> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
> ---
> drivers/pci/pci.c | 17 ++++-------------
> drivers/pci/pci.h | 9 +++++++++
> 2 files changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index dce32ce..2ef4030 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5780,19 +5780,10 @@ enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev)
> * where only 2.5 GT/s and 5.0 GT/s speeds were defined.
> */
> pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2);
> - if (lnkcap2) { /* PCIe r3.0-compliant */
> - if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_32_0GB)
> - return PCIE_SPEED_32_0GT;
> - else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB)
> - return PCIE_SPEED_16_0GT;
> - else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)
> - return PCIE_SPEED_8_0GT;
> - else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB)
> - return PCIE_SPEED_5_0GT;
> - else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB)
> - return PCIE_SPEED_2_5GT;
> - return PCI_SPEED_UNKNOWN;
> - }
> +
> + /* PCIe r3.0-compliant */
> + if (lnkcap2)
> + return PCIE_LNKCAP2_SLS2SPEED(lnkcap2);
>
> pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
> if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_5_0GB)
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 5e1f810..3d988e9 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -290,6 +290,15 @@ void pci_disable_bridge_window(struct pci_dev *dev);
> struct pci_bus *pci_bus_get(struct pci_bus *bus);
> void pci_bus_put(struct pci_bus *bus);
>
> +/* PCIe link information from Link Capabilities 2 */
> +#define PCIE_LNKCAP2_SLS2SPEED(lnkcap2) \
> + ((lnkcap2) & PCI_EXP_LNKCAP2_SLS_32_0GB ? PCIE_SPEED_32_0GT : \
> + (lnkcap2) & PCI_EXP_LNKCAP2_SLS_16_0GB ? PCIE_SPEED_16_0GT : \
> + (lnkcap2) & PCI_EXP_LNKCAP2_SLS_8_0GB ? PCIE_SPEED_8_0GT : \
> + (lnkcap2) & PCI_EXP_LNKCAP2_SLS_5_0GB ? PCIE_SPEED_5_0GT : \
> + (lnkcap2) & PCI_EXP_LNKCAP2_SLS_2_5GB ? PCIE_SPEED_2_5GT : \
> + PCI_SPEED_UNKNOWN)
> +
> /* PCIe link information */
> #define PCI_SPEED2STR(speed) \
> ((speed) == PCI_SPEED_UNKNOWN ? "Unknown speed" : \
> --
> 2.8.1
>
next prev parent reply other threads:[~2020-02-05 18:54 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-15 9:04 [PATCH 0/6] Improve link speed presentation process Yicong Yang
2020-01-15 9:04 ` [PATCH 1/6] PCI: add 32 GT/s decoding in some macros Yicong Yang
2020-01-15 9:04 ` [PATCH 2/6] PCI: Make pci_bus_speed_strings[] public Yicong Yang
2020-02-05 18:35 ` Bjorn Helgaas
2020-02-06 1:47 ` Yicong Yang
2020-01-15 9:04 ` [PATCH 3/6] PCI: Add comments for link speed info arrays Yicong Yang
2020-01-15 9:04 ` [PATCH 4/6] PCI: Improve and rename PCIE_SPEED2STR macro Yicong Yang
2020-02-05 18:50 ` Bjorn Helgaas
2020-02-06 1:50 ` Yicong Yang
2020-01-15 9:04 ` [PATCH 5/6] PCI: Add PCIE_LNKCAP2_SLS2SPEED macro Yicong Yang
2020-02-05 18:54 ` Bjorn Helgaas [this message]
2020-02-06 1:53 ` Yicong Yang
2020-01-15 9:04 ` [PATCH 6/6] PCI: Reduce redundancy in current_link_speed_show() Yicong Yang
2020-02-05 9:37 ` [PATCH 0/6] Improve link speed presentation process Yicong Yang
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=20200205185446.GA231340@google.com \
--to=helgaas@kernel.org \
--cc=f.fangjian@huawei.com \
--cc=linux-pci@vger.kernel.org \
--cc=yangyicong@hisilicon.com \
/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).