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To save small bit of CPU time, hide part of SNTF register read latency

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behind other reads.
This commit is contained in:
Alexander Motin 2009-09-06 21:22:24 +00:00
parent 7fc019af65
commit aed39f0d65
1 changed files with 7 additions and 9 deletions
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16
sys/dev/ahci/ahci.c
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@ -891,16 +891,12 @@ ahci_phy_check_events(device_t dev)
}
static void
ahci_notify_events(device_t dev)
ahci_notify_events(device_t dev, u_int32_t status)
{
struct ahci_channel *ch = device_get_softc(dev);
struct cam_path *dpath;
u_int32_t status;
int i;
status = ATA_INL(ch->r_mem, AHCI_P_SNTF);
if (status == 0)
return;
ATA_OUTL(ch->r_mem, AHCI_P_SNTF, status);
if (bootverbose)
device_printf(dev, "SNTF 0x%04x\n", status);
@ -948,7 +944,7 @@ ahci_ch_intr(void *data)
{
device_t dev = (device_t)data;
struct ahci_channel *ch = device_get_softc(dev);
uint32_t istatus, cstatus, sstatus, ok, err;
uint32_t istatus, sstatus, cstatus, sntf = 0, ok, err;
enum ahci_err_type et;
int i, ccs, ncq_err = 0;
@ -958,8 +954,10 @@ ahci_ch_intr(void *data)
return;
ATA_OUTL(ch->r_mem, AHCI_P_IS, istatus);
/* Read command statuses. */
cstatus = ATA_INL(ch->r_mem, AHCI_P_CI);
sstatus = ATA_INL(ch->r_mem, AHCI_P_SACT);
cstatus = ATA_INL(ch->r_mem, AHCI_P_CI);
if ((istatus & AHCI_P_IX_SDB) && (ch->caps & AHCI_CAP_SSNTF))
sntf = ATA_INL(ch->r_mem, AHCI_P_SNTF);
/* Process PHY events */
if (istatus & (AHCI_P_IX_PRC | AHCI_P_IX_PC))
ahci_phy_check_events(dev);
@ -1023,8 +1021,8 @@ ahci_ch_intr(void *data)
ahci_issue_read_log(dev);
}
/* Process NOTIFY events */
if ((istatus & AHCI_P_IX_SDB) && (ch->caps & AHCI_CAP_SSNTF))
ahci_notify_events(dev);
if (sntf)
ahci_notify_events(dev, sntf);
}
/* Must be called with channel locked. */