Sorry for the wrong '[PATCH 1/4]' in the tile. This is a single patch, please ignore this email and I'll re-send it. > -----Original Message----- > From: Zhuo, Qiuxu > Sent: Monday, August 14, 2017 11:47 PM > To: jdelvare@xxxxxxxx; wsa@xxxxxxxxxxxxx > Cc: Luck, Tony <tony.luck@xxxxxxxxx>; Westerberg, Mika > <mika.westerberg@xxxxxxxxx>; bp@xxxxxxxxx; linux-i2c@xxxxxxxxxxxxxxx; Zhuo, > Qiuxu <qiuxu.zhuo@xxxxxxxxx> > Subject: [PATCH 1/4] i2c: i801: Restore the presence state of P2SB PCI device > after reading BAR > > Sun, Yunying reported the following failure on Denverton micro-server: > > EDAC DEBUG: pnd2_init: > EDAC DEBUG: pnd2_probe: > EDAC DEBUG: dnv_rd_reg: Read b_cr_tolud_pci=00000000_80000000 EDAC > DEBUG: dnv_rd_reg: Read b_cr_touud_lo_pci=00000000_80000000 > EDAC DEBUG: dnv_rd_reg: Read b_cr_touud_hi_pci=00000000_00000004 > EDAC DEBUG: dnv_rd_reg: Read > b_cr_asym_mem_region0_mchbar=00000000_00000000 > EDAC DEBUG: dnv_rd_reg: Read > b_cr_asym_mem_region1_mchbar=00000000_00000000 > EDAC DEBUG: dnv_rd_reg: Read > b_cr_mot_out_base_mchbar=00000000_00000000 > EDAC DEBUG: dnv_rd_reg: Read > b_cr_mot_out_mask_mchbar=00000000_00000000 > EDAC pnd2: Failed to register device with error -19. > > On Denverton micro-server, the presence of the P2SB bridge PCI device is > enabled or disabled by the item 'RelaxSecConf' in BIOS setup menu. When > 'RelaxSecConf' is enabled, the P2SB PCI device is present and the pnd2_edac > EDAC driver also uses it to get BAR. Hiding the P2SB PCI device caused the > pnd2_edac EDAC driver failed to get BAR then reported the above failure. > > Therefor, store the presence state of P2SB PCI device before unhiding it for > reading BAR and restore the presence state after reading BAR. > > Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx> > Reported-and-tested-by: Yunying Sun <yunying.sun@xxxxxxxxx> > --- > drivers/i2c/busses/i2c-i801.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index > c9536e1..e114e4e 100644 > --- a/drivers/i2c/busses/i2c-i801.c > +++ b/drivers/i2c/busses/i2c-i801.c > @@ -1332,6 +1332,7 @@ static void i801_add_tco(struct i801_priv *priv) > u32 tco_base, tco_ctl; > u32 base_addr, ctrl_val; > u64 base64_addr; > + u8 hidden; > > if (!(priv->features & FEATURE_TCO)) > return; > @@ -1376,8 +1377,10 @@ static void i801_add_tco(struct i801_priv *priv) > > devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 1); > > - /* Unhide the P2SB device */ > - pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, 0x0); > + /* Unhide the P2SB device, if it is hidden */ > + pci_bus_read_config_byte(pci_dev->bus, devfn, 0xe1, &hidden); > + if (hidden) > + pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, 0x0); > > pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR, > &base_addr); > base64_addr = base_addr & 0xfffffff0; > @@ -1385,8 +1388,9 @@ static void i801_add_tco(struct i801_priv *priv) > pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR + 0x4, > &base_addr); > base64_addr |= (u64)base_addr << 32; > > - /* Hide the P2SB device */ > - pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, 0x1); > + /* Hide the P2SB device, if it was hidden before */ > + if (hidden) > + pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, hidden); > spin_unlock(&p2sb_spinlock); > > res = &tco_res[ICH_RES_MEM_OFF]; > -- > 2.9.0.GIT
