From: Sasha Neftin sasha.neftin@intel.com
[ Upstream commit 44a13a5d99c71bf9e1676d9e51679daf4d7b3d73 ]
We should decode the latency and the max_latency before directly compare. The latency should be presented as lat_enc = scale x value: lat_enc_d = (lat_enc & 0x0x3ff) x (1U << (5*((max_ltr_enc & 0x1c00)
10)))
Fixes: cf8fb73c23aa ("e1000e: add support for LTR on I217/I218") Suggested-by: Yee Li seven.yi.lee@gmail.com Signed-off-by: Sasha Neftin sasha.neftin@intel.com Tested-by: Dvora Fuxbrumer dvorax.fuxbrumer@linux.intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/e1000e/ich8lan.c | 14 +++++++++++++- drivers/net/ethernet/intel/e1000e/ich8lan.h | 3 +++ 2 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c index 485b9cc53f8b..cd7403d09c3d 100644 --- a/drivers/net/ethernet/intel/e1000e/ich8lan.c +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c @@ -1010,6 +1010,8 @@ static s32 e1000_platform_pm_pch_lpt(struct e1000_hw *hw, bool link) { u32 reg = link << (E1000_LTRV_REQ_SHIFT + E1000_LTRV_NOSNOOP_SHIFT) | link << E1000_LTRV_REQ_SHIFT | E1000_LTRV_SEND; + u16 max_ltr_enc_d = 0; /* maximum LTR decoded by platform */ + u16 lat_enc_d = 0; /* latency decoded */ u16 lat_enc = 0; /* latency encoded */
if (link) { @@ -1063,7 +1065,17 @@ static s32 e1000_platform_pm_pch_lpt(struct e1000_hw *hw, bool link) E1000_PCI_LTR_CAP_LPT + 2, &max_nosnoop); max_ltr_enc = max_t(u16, max_snoop, max_nosnoop);
- if (lat_enc > max_ltr_enc) + lat_enc_d = (lat_enc & E1000_LTRV_VALUE_MASK) * + (1U << (E1000_LTRV_SCALE_FACTOR * + ((lat_enc & E1000_LTRV_SCALE_MASK) + >> E1000_LTRV_SCALE_SHIFT))); + + max_ltr_enc_d = (max_ltr_enc & E1000_LTRV_VALUE_MASK) * + (1U << (E1000_LTRV_SCALE_FACTOR * + ((max_ltr_enc & E1000_LTRV_SCALE_MASK) + >> E1000_LTRV_SCALE_SHIFT))); + + if (lat_enc_d > max_ltr_enc_d) lat_enc = max_ltr_enc; }
diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.h b/drivers/net/ethernet/intel/e1000e/ich8lan.h index 34c551e322eb..3a16c457c8dd 100644 --- a/drivers/net/ethernet/intel/e1000e/ich8lan.h +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.h @@ -284,8 +284,11 @@
/* Latency Tolerance Reporting */ #define E1000_LTRV 0x000F8 +#define E1000_LTRV_VALUE_MASK 0x000003FF #define E1000_LTRV_SCALE_MAX 5 #define E1000_LTRV_SCALE_FACTOR 5 +#define E1000_LTRV_SCALE_SHIFT 10 +#define E1000_LTRV_SCALE_MASK 0x00001C00 #define E1000_LTRV_REQ_SHIFT 15 #define E1000_LTRV_NOSNOOP_SHIFT 16 #define E1000_LTRV_SEND (1 << 30)