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author | Stephen Rothwell <sfr@canb.auug.org.au> | 2017-06-02 12:53:28 +1000 |
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committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2017-06-02 12:53:28 +1000 |
commit | 68fc5e40a7b184a51cb9ec37f05f9a8c093e6213 (patch) | |
tree | 7b683d9a566350b3260ab31adfdccb42d8d8bf80 /Documentation | |
parent | e18831c9e2e5d5da50d0c6b2f9cea306d9616120 (diff) | |
parent | 8e3c0499d0c92e96cb9295d45f1ac3784ecad8ec (diff) |
Merge remote-tracking branch 'tip/auto-latest'
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/IRQ-domain.txt | 41 | ||||
-rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 9 |
2 files changed, 48 insertions, 2 deletions
diff --git a/Documentation/IRQ-domain.txt b/Documentation/IRQ-domain.txt index 82001a25a14b..1f246eb25ca5 100644 --- a/Documentation/IRQ-domain.txt +++ b/Documentation/IRQ-domain.txt @@ -231,5 +231,42 @@ needs to: 4) No need to implement irq_domain_ops.map and irq_domain_ops.unmap, they are unused with hierarchy irq_domain. -Hierarchy irq_domain may also be used to support other architectures, -such as ARM, ARM64 etc. +Hierarchy irq_domain is in no way x86 specific, and is heavily used to +support other architectures, such as ARM, ARM64 etc. + +=== Debugging === + +If you switch on CONFIG_IRQ_DOMAIN_DEBUG (which depends on +CONFIG_IRQ_DOMAIN and CONFIG_DEBUG_FS), you will find a new file in +your debugfs mount point, called irq_domain_mapping. This file +contains a live snapshot of all the IRQ domains in the system: + + name mapped linear-max direct-max devtree-node + pl061 8 8 0 /smb/gpio@e0080000 + pl061 8 8 0 /smb/gpio@e1050000 + pMSI 0 0 0 /interrupt-controller@e1101000/v2m@e0080000 + MSI 37 0 0 /interrupt-controller@e1101000/v2m@e0080000 + GICv2m 37 0 0 /interrupt-controller@e1101000/v2m@e0080000 + GICv2 448 448 0 /interrupt-controller@e1101000 + +it also iterates over the interrupts to display their mapping in the +domains, and makes the domain stacking visible: + + +irq hwirq chip name chip data active type domain + 1 0x00019 GICv2 0xffff00000916bfd8 * LINEAR GICv2 + 2 0x0001d GICv2 0xffff00000916bfd8 LINEAR GICv2 + 3 0x0001e GICv2 0xffff00000916bfd8 * LINEAR GICv2 + 4 0x0001b GICv2 0xffff00000916bfd8 * LINEAR GICv2 + 5 0x0001a GICv2 0xffff00000916bfd8 LINEAR GICv2 +[...] + 96 0x81808 MSI 0x (null) RADIX MSI + 96+ 0x00063 GICv2m 0xffff8003ee116980 RADIX GICv2m + 96+ 0x00063 GICv2 0xffff00000916bfd8 LINEAR GICv2 + 97 0x08800 MSI 0x (null) * RADIX MSI + 97+ 0x00064 GICv2m 0xffff8003ee116980 * RADIX GICv2m + 97+ 0x00064 GICv2 0xffff00000916bfd8 * LINEAR GICv2 + +Here, interrupts 1-5 are only using a single domain, while 96 and 97 +are build out of a stack of three domain, each level performing a +particular function. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 0f5c3b4347c6..8c2ede864013 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2136,6 +2136,12 @@ memmap=nn[KMG]@ss[KMG] [KNL] Force usage of a specific region of memory. Region of memory to be used is from ss to ss+nn. + If @ss[KMG] is omitted, it is equivalent to mem=nn[KMG], + which limits max address to nn[KMG]. + Multiple different regions can be specified, + comma delimited. + Example: + memmap=100M@2G,100M#3G,1G!1024G memmap=nn[KMG]#ss[KMG] [KNL,ACPI] Mark specific memory as ACPI data. @@ -2148,6 +2154,9 @@ memmap=64K$0x18690000 or memmap=0x10000$0x18690000 + Some bootloaders may need an escape character before '$', + like Grub2, otherwise '$' and the following number + will be eaten. memmap=nn[KMG]!ss[KMG] [KNL,X86] Mark specific memory as protected. |