diff options
Diffstat (limited to 'drivers/net/ethernet/intel/e1000e/netdev.c')
| -rw-r--r-- | drivers/net/ethernet/intel/e1000e/netdev.c | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 02c64bcda71d..0d3c00deb160 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -4275,7 +4275,7 @@ static cycle_t e1000e_cyclecounter_read(const struct cyclecounter *cc) struct e1000_adapter *adapter = container_of(cc, struct e1000_adapter, cc); struct e1000_hw *hw = &adapter->hw; - u32 systimel_1, systimel_2, systimeh; + u32 systimel, systimeh; cycle_t systim, systim_next; /* SYSTIMH latching upon SYSTIML read does not work well. * This means that if SYSTIML overflows after we read it but before @@ -4283,21 +4283,21 @@ static cycle_t e1000e_cyclecounter_read(const struct cyclecounter *cc) * will experience a huge non linear increment in the systime value * to fix that we test for overflow and if true, we re-read systime. */ - systimel_1 = er32(SYSTIML); + systimel = er32(SYSTIML); systimeh = er32(SYSTIMH); - systimel_2 = er32(SYSTIML); - /* Check for overflow. If there was no overflow, use the values */ - if (systimel_1 <= systimel_2) { - systim = (cycle_t)systimel_1; - systim |= (cycle_t)systimeh << 32; - } else { - /* There was an overflow, read again SYSTIMH, and use - * systimel_2 - */ - systimeh = er32(SYSTIMH); - systim = (cycle_t)systimel_2; - systim |= (cycle_t)systimeh << 32; + /* Is systimel is so large that overflow is possible? */ + if (systimel >= (u32)0xffffffff - E1000_TIMINCA_INCVALUE_MASK) { + u32 systimel_2 = er32(SYSTIML); + if (systimel > systimel_2) { + /* There was an overflow, read again SYSTIMH, and use + * systimel_2 + */ + systimeh = er32(SYSTIMH); + systimel = systimel_2; + } } + systim = (cycle_t)systimel; + systim |= (cycle_t)systimeh << 32; if ((hw->mac.type == e1000_82574) || (hw->mac.type == e1000_82583)) { u64 time_delta, rem, temp; |