diff options
author | Venki Pallipadi | 2007-10-12 23:04:23 +0200 |
---|---|---|
committer | Thomas Gleixner | 2007-10-12 23:04:23 +0200 |
commit | d54bd57d6580250e6551261f3b15c45a9d90c77b (patch) | |
tree | 12cb06b4adb9494e67cefdc691643e333fef3b91 /arch | |
parent | 610bf2f143b9c5cda768a2d428d66d3a16769930 (diff) |
x86: HPET force enable o ICH7 and later
Force detect and/or enable HPET on ICH chipsets. This patch just handles the
detection part and following patches use this information. Adds a function to
repeat the force enabling during resume time.
Using HPET this way, instead of PIT increases the time CPUs can reside in
C-state when system is totally idle. On my test system with Core 2 Duo,
average C-state residency goes up from ~20mS to ~80mS.
[ Build fixed from Andrew Morton ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/kernel/quirks.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c index 6722469c2633..d3ac703867d6 100644 --- a/arch/x86/kernel/quirks.c +++ b/arch/x86/kernel/quirks.c @@ -4,6 +4,8 @@ #include <linux/pci.h> #include <linux/irq.h> +#include <asm/hpet.h> + #if defined(CONFIG_X86_IO_APIC) && defined(CONFIG_SMP) && defined(CONFIG_PCI) static void __devinit quirk_intel_irqbalance(struct pci_dev *dev) @@ -47,3 +49,103 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7320_MCH, quir DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7525_MCH, quirk_intel_irqbalance); DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7520_MCH, quirk_intel_irqbalance); #endif + +#if defined(CONFIG_HPET_TIMER) +unsigned long force_hpet_address; + +static void __iomem *rcba_base; + +void ich_force_hpet_resume(void) +{ + u32 val; + + if (!force_hpet_address) + return; + + if (rcba_base == NULL) + BUG(); + + /* read the Function Disable register, dword mode only */ + val = readl(rcba_base + 0x3404); + if (!(val & 0x80)) { + /* HPET disabled in HPTC. Trying to enable */ + writel(val | 0x80, rcba_base + 0x3404); + } + + val = readl(rcba_base + 0x3404); + if (!(val & 0x80)) + BUG(); + else + printk(KERN_DEBUG "Force enabled HPET at resume\n"); + + return; +} + +static void ich_force_enable_hpet(struct pci_dev *dev) +{ + u32 val; + u32 uninitialized_var(rcba); + int err = 0; + + if (hpet_address || force_hpet_address) + return; + + pci_read_config_dword(dev, 0xF0, &rcba); + rcba &= 0xFFFFC000; + if (rcba == 0) { + printk(KERN_DEBUG "RCBA disabled. Cannot force enable HPET\n"); + return; + } + + /* use bits 31:14, 16 kB aligned */ + rcba_base = ioremap_nocache(rcba, 0x4000); + if (rcba_base == NULL) { + printk(KERN_DEBUG "ioremap failed. Cannot force enable HPET\n"); + return; + } + + /* read the Function Disable register, dword mode only */ + val = readl(rcba_base + 0x3404); + + if (val & 0x80) { + /* HPET is enabled in HPTC. Just not reported by BIOS */ + val = val & 0x3; + force_hpet_address = 0xFED00000 | (val << 12); + printk(KERN_DEBUG "Force enabled HPET at base address 0x%lx\n", + force_hpet_address); + iounmap(rcba_base); + return; + } + + /* HPET disabled in HPTC. Trying to enable */ + writel(val | 0x80, rcba_base + 0x3404); + + val = readl(rcba_base + 0x3404); + if (!(val & 0x80)) { + err = 1; + } else { + val = val & 0x3; + force_hpet_address = 0xFED00000 | (val << 12); + } + + if (err) { + force_hpet_address = 0; + iounmap(rcba_base); + printk(KERN_DEBUG "Failed to force enable HPET\n"); + } else { + printk(KERN_DEBUG "Force enabled HPET at base address 0x%lx\n", + force_hpet_address); + } +} + +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_0, + ich_force_enable_hpet); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_1, + ich_force_enable_hpet); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_1, + ich_force_enable_hpet); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_31, + ich_force_enable_hpet); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH8_1, + ich_force_enable_hpet); +#endif |