From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Neftin Date: Tue, 26 Oct 2021 11:47:55 +0300 Subject: [Intel-wired-lan] [PATCH v2] e1000e: Add a delay to let ME unconfigure s0ix when DPG_EXIT_DONE is already flagged In-Reply-To: <20211026065112.1366205-1-kai.heng.feng@canonical.com> References: <20211026065112.1366205-1-kai.heng.feng@canonical.com> Message-ID: <04ed8307-ab1f-59d6-4454-c759ce4a453b@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: 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 > --- > 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 > /* 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 >