Messages in this thread | | | Date | Fri, 29 Oct 2021 12:14:10 +0300 | Subject | Re: [PATCH v2] e1000e: Add a delay to let ME unconfigure s0ix when DPG_EXIT_DONE is already flagged | From | Sasha Neftin <> |
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On 10/27/2021 01:50, Kai-Heng Feng wrote: > On Tue, Oct 26, 2021 at 4:48 PM Sasha Neftin <sasha.neftin@intel.com> wrote: >> >> On 10/26/2021 09:51, Kai-Heng Feng wrote: >>> On some ADL platforms, DPG_EXIT_DONE is always flagged so e1000e resume >>> polling logic doesn't wait until ME really unconfigures s0ix. >>> >>> So check DPG_EXIT_DONE before issuing EXIT_DPG, and if it's already >>> flagged, wait for 1 second to let ME unconfigure s0ix. >>> >>> Fixes: 3e55d231716e ("e1000e: Add handshake with the CSME to support S0ix") >>> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214821 >>> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> >>> --- >>> v2: >>> Add missing "Fixes:" tag >>> >>> drivers/net/ethernet/intel/e1000e/netdev.c | 7 +++++++ >>> 1 file changed, 7 insertions(+) >>> >>> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c >>> index 44e2dc8328a22..cd81ba00a6bc9 100644 >>> --- a/drivers/net/ethernet/intel/e1000e/netdev.c >>> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c >>> @@ -6493,14 +6493,21 @@ static void e1000e_s0ix_exit_flow(struct e1000_adapter *adapter) >>> u32 mac_data; >>> u16 phy_data; >>> u32 i = 0; >>> + bool dpg_exit_done; >>> >>> if (er32(FWSM) & E1000_ICH_FWSM_FW_VALID) { >>> + dpg_exit_done = er32(EXFWSM) & E1000_EXFWSM_DPG_EXIT_DONE; >>> /* Request ME unconfigure the device from S0ix */ >>> mac_data = er32(H2ME); >>> mac_data &= ~E1000_H2ME_START_DPG; >>> mac_data |= E1000_H2ME_EXIT_DPG; >>> ew32(H2ME, mac_data); >>> >>> + if (dpg_exit_done) { >>> + e_warn("DPG_EXIT_DONE is already flagged. This is a firmware bug\n"); >>> + msleep(1000); >>> + } >> Thanks for working on the enablement. >> The delay approach is fragile. We need to work with CSME folks to >> understand why _DPG_EXIT_DONE indication is wrong on some ADL platforms. >> Could you provide CSME/BIOS version? dmidecode -t 0 and cat >> /sys/class/mei/mei0/fw_ver > > $ sudo dmidecode -t 0 > # dmidecode 3.2 > Getting SMBIOS data from sysfs. > SMBIOS 3.4 present. > # SMBIOS implementations newer than version 3.2.0 are not > # fully supported by this version of dmidecode. > > Handle 0x0001, DMI type 0, 26 bytes > BIOS Information > Vendor: Dell Inc. > Version: 0.12.68 > Release Date: 10/01/2021 > ROM Size: 48 MB > Characteristics: > PCI is supported > PNP is supported > BIOS is upgradeable > BIOS shadowing is allowed > Boot from CD is supported > Selectable boot is supported > EDD is supported > Print screen service is supported (int 5h) > 8042 keyboard services are supported (int 9h) > Serial services are supported (int 14h) > Printer services are supported (int 17h) > ACPI is supported > USB legacy is supported > BIOS boot specification is supported > Function key-initiated network boot is supported > Targeted content distribution is supported > UEFI is supported > BIOS Revision: 0.12 > > $ cat /sys/class/mei/mei0/fw_ver > 0:16.0.15.1518 > 0:16.0.15.1518 > 0:16.0.15.1518 > Thank you Kai-Heng. The _DPG_EXIT_DONE bit indication comes from the EXFWSM register controlled by the CSME. We have only read access. I realized that this indication was set to 1 even before our request to unconfigure the s0ix settings from the CSME. I am wondering. Does after a ~ 1s delay (or less, or more) _DPG_EXIT_DONE indication eventually change by CSME to 0? (is it consistently) >>> /* Poll up to 2.5 seconds for ME to unconfigure DPG. >>> * If this takes more than 1 second, show a warning indicating a >>> * firmware bug >>>
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