On 2020/2/6 2:54, Bjorn Helgaas wrote:
> 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?
Seems I used improper description here. I'll correct it in next version.
Thanks,
Yang
>
>> Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
>> ---
>> 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
>>
> .
>
