From bc8f10babcc27c1f4d8e80d91cc543eabf9125c4 Mon Sep 17 00:00:00 2001 From: Qiuxu Zhuo Date: Mon, 14 Aug 2017 23:49:05 +0800 Subject: EDAC, pnd2: Properly toggle hidden state for P2SB PCI device Properly handle hidden state of P2SB PCI device (DEV:D, FUN:0) for Apollo Lake. Signed-off-by: Qiuxu Zhuo Cc: Tony Luck Cc: linux-edac Link: http://lkml.kernel.org/r/20170814154905.21707-1-qiuxu.zhuo@intel.com Signed-off-by: Borislav Petkov --- drivers/edac/pnd2_edac.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'drivers/edac') diff --git a/drivers/edac/pnd2_edac.c b/drivers/edac/pnd2_edac.c index 89cdd9a7a733..4395c84cdcbf 100644 --- a/drivers/edac/pnd2_edac.c +++ b/drivers/edac/pnd2_edac.c @@ -161,8 +161,12 @@ static int _apl_rd_reg(int port, int off, int op, u32 *data) { int retries = 0xff, ret; u16 status; + u8 hidden; - P2SB_WRITE(byte, P2SB_HIDE_OFF, 0); + /* Unhide the P2SB device, if it's hidden */ + P2SB_READ(byte, P2SB_HIDE_OFF, &hidden); + if (hidden) + P2SB_WRITE(byte, P2SB_HIDE_OFF, 0); if (p2sb_is_busy(&status)) { ret = -EAGAIN; @@ -185,7 +189,9 @@ static int _apl_rd_reg(int port, int off, int op, u32 *data) P2SB_READ(dword, P2SB_DATA_OFF, data); ret = (status >> 1) & 0x3; out: - P2SB_WRITE(byte, P2SB_HIDE_OFF, 1); + /* Hide the P2SB device, if it was hidden before */ + if (hidden) + P2SB_WRITE(byte, P2SB_HIDE_OFF, hidden); return ret; } -- cgit v1.2.3-59-g8ed1b