iommu/amd: Document ivrs_ioapic and ivrs_hpet parameters

Document the new kernel commandline parameters in the
appropriate file.

Reviewed-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 4609e81dbc37fc2dbfa005ff607890df3a8bbc6b..2848b1b4e058e825b5dd38c908722503392ad3a8 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1226,6 +1226,20 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
        iucv=           [HW,NET]
 
+       ivrs_ioapic     [HW,X86_64]
+                       Provide an override to the IOAPIC-ID<->DEVICE-ID
+                       mapping provided in the IVRS ACPI table. For
+                       example, to map IOAPIC-ID decimal 10 to
+                       PCI device 00:14.0 write the parameter as:
+                               ivrs_ioapic[10]=00:14.0
+
+       ivrs_hpet       [HW,X86_64]
+                       Provide an override to the HPET-ID<->DEVICE-ID
+                       mapping provided in the IVRS ACPI table. For
+                       example, to map HPET-ID decimal 0 to
+                       PCI device 00:14.0 write the parameter as:
+                               ivrs_hpet[0]=00:14.0
+
        js=             [HW,JOY] Analog joystick
                        See Documentation/input/joystick.txt.