diff options
Diffstat (limited to 'xen/arch/x86/hpet.c')
| -rw-r--r-- | xen/arch/x86/hpet.c | 31 |
1 files changed, 29 insertions, 2 deletions
diff --git a/xen/arch/x86/hpet.c b/xen/arch/x86/hpet.c index ca6a0297a0..e0b8659554 100644 --- a/xen/arch/x86/hpet.c +++ b/xen/arch/x86/hpet.c @@ -722,12 +722,14 @@ int hpet_legacy_irq_tick(void) return 1; } +static u32 *hpet_boot_cfg; + u64 hpet_setup(void) { static u64 hpet_rate; static u32 system_reset_latch; u32 hpet_id, hpet_period, cfg; - int i; + unsigned int i, last; if ( system_reset_latch == system_reset_counter ) return hpet_rate; @@ -753,13 +755,20 @@ u64 hpet_setup(void) return 0; } + last = (hpet_id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT; + hpet_boot_cfg = xmalloc_array(u32, 2 + last); + cfg = hpet_read32(HPET_CFG); + if ( hpet_boot_cfg ) + *hpet_boot_cfg = cfg; cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY); hpet_write32(cfg, HPET_CFG); - for ( i = 0; i <= ((hpet_id >> 8) & 31); i++ ) + for ( i = 0; i <= last; ++i ) { cfg = hpet_read32(HPET_Tn_CFG(i)); + if ( hpet_boot_cfg ) + hpet_boot_cfg[i + 1] = cfg; cfg &= ~HPET_TN_ENABLE; hpet_write32(cfg, HPET_Tn_CFG(i)); } @@ -773,3 +782,21 @@ u64 hpet_setup(void) return hpet_rate; } + +void hpet_disable(void) +{ + unsigned int i; + u32 id; + + if ( !hpet_boot_cfg ) + return; + + hpet_write32(*hpet_boot_cfg & ~HPET_CFG_ENABLE, HPET_CFG); + + id = hpet_read32(HPET_ID); + for ( i = 0; i <= ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT); ++i ) + hpet_write32(hpet_boot_cfg[i + 1], HPET_Tn_CFG(i)); + + if ( *hpet_boot_cfg & HPET_CFG_ENABLE ) + hpet_write32(*hpet_boot_cfg, HPET_CFG); +} |