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Commit d4c4d094 authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
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x86: if acpi=off, force setting the mmconf for fam10h 



some BIOS only let AMD fam 10h handle bus0, and nvidia mcp55/ck804
to handle other buses. at that case MCFG will cover all over them.

but with acpi=off, we can not use MCFG. this patch will double check
the busnbits, and if it is less handling 256 bues, and acpi=off
will forcely reset the mmconf in msr, so we still use mmconf in above case.

Signed-off-by: default avatarYinghai Lu <yinghai.lu@sun.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 7fd0da40

arch/x86/kernel/setup_64.c

+15 −8
Original line number Diff line number Diff line
@@ -751,6 +751,12 @@ static void __cpuinit fam10h_check_enable_mmcfg(struct cpuinfo_x86 *c) 


	/* try to make sure that AP's setting is identical to BSP setting */

	if (val & FAM10H_MMIO_CONF_ENABLE) {

		unsigned busnbits;

		busnbits = (val >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &

			FAM10H_MMIO_CONF_BUSRANGE_MASK;



		/* only trust the one handle 256 buses, if acpi=off */

		if (!acpi_pci_disabled || busnbits >= 8) {

			u64 base;

			base = val & (0xffffULL << 32);

			if (fam10h_pci_mmconf_base_status <= 0) {
@@ -760,6 +766,7 @@ static void __cpuinit fam10h_check_enable_mmcfg(struct cpuinfo_x86 *c) 
			} else if (fam10h_pci_mmconf_base ==  base)

				return;

		}

	}



	/*

	 * if it is not enabled, try to enable it and assume only one segment