Re: [PATCH v11 02/16] PCI/RCEC: Add RCEC class code and extended capability

From: Kelley, Sean V
Date: Tue Nov 17 2020 - 17:39:54 EST


Hi Sathya,

Thanks for reviewing

> On Nov 17, 2020, at 12:07 PM, Kuppuswamy, Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote:
>
> Hi,
>
> On 11/17/20 11:19 AM, Sean V Kelley wrote:
>> From: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
>> A PCIe Root Complex Event Collector (RCEC) has base class 0x08, sub-class
>> 0x07, and programming interface 0x00. Add the class code 0x0807 to
>> identify RCEC devices and add #defines for the RCEC Endpoint Association
>> Extended Capability.
>> See PCIe r5.0, sec 1.3.4 ("Root Complex Event Collector") and sec 7.9.10
>> ("Root Complex Event Collector Endpoint Association Extended Capability").
> Why not merge this change with usage patch ? Keeping changes together will help
> in case of reverting the code.

These are spec derived values that have been absent until now. They could be combined with usage.

Sean



>> Link: https://lore.kernel.org/r/20201002184735.1229220-2-seanvk.dev@xxxxxxxxxxxxxxxx
>> Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
>> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>> ---
>> include/linux/pci_ids.h | 1 +
>> include/uapi/linux/pci_regs.h | 7 +++++++
>> 2 files changed, 8 insertions(+)
>> diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
>> index 1ab1e24bcbce..d8156a5dbee8 100644
>> --- a/include/linux/pci_ids.h
>> +++ b/include/linux/pci_ids.h
>> @@ -81,6 +81,7 @@
>> #define PCI_CLASS_SYSTEM_RTC 0x0803
>> #define PCI_CLASS_SYSTEM_PCI_HOTPLUG 0x0804
>> #define PCI_CLASS_SYSTEM_SDHCI 0x0805
>> +#define PCI_CLASS_SYSTEM_RCEC 0x0807
>> #define PCI_CLASS_SYSTEM_OTHER 0x0880
>> #define PCI_BASE_CLASS_INPUT 0x09
>> diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
>> index a95d55f9f257..bccd3e35cb65 100644
>> --- a/include/uapi/linux/pci_regs.h
>> +++ b/include/uapi/linux/pci_regs.h
>> @@ -831,6 +831,13 @@
>> #define PCI_PWR_CAP_BUDGET(x) ((x) & 1) /* Included in system budget */
>> #define PCI_EXT_CAP_PWR_SIZEOF 16
>> +/* Root Complex Event Collector Endpoint Association */
>> +#define PCI_RCEC_RCIEP_BITMAP 4 /* Associated Bitmap for RCiEPs */
>> +#define PCI_RCEC_BUSN 8 /* RCEC Associated Bus Numbers */
>> +#define PCI_RCEC_BUSN_REG_VER 0x02 /* Least version with BUSN present */
>> +#define PCI_RCEC_BUSN_NEXT(x) (((x) >> 8) & 0xff)
>> +#define PCI_RCEC_BUSN_LAST(x) (((x) >> 16) & 0xff)
>> +
>> /* Vendor-Specific (VSEC, PCI_EXT_CAP_ID_VNDR) */
>> #define PCI_VNDR_HEADER 4 /* Vendor-Specific Header */
>> #define PCI_VNDR_HEADER_ID(x) ((x) & 0xffff)
>
> --
> Sathyanarayanan Kuppuswamy
> Linux Kernel Developer