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authorTakashi Iwai <tiwai@suse.de>2019-09-10 14:03:08 +0300
committerTakashi Iwai <tiwai@suse.de>2019-09-10 14:03:08 +0300
commit7711fb7dac1ab77fd1b4d948f4647a569e4a1ae2 (patch)
treedd35ad21e0eb13572757dab279ae41f6d953baed /Documentation/virt/kvm/devices/mpic.txt
parent789492f0c86505e63369907bcb1afdf52dec9366 (diff)
parentbb831786117519fc16dfd3eaa7b84e4f6bbb8d99 (diff)
downloadlinux-7711fb7dac1ab77fd1b4d948f4647a569e4a1ae2.tar.xz
Merge tag 'asoc-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next
ASoC: Updates for v5.4 Quite a big update this time around, particularly in the core where we've had a lot of cleanups from Morimoto-san - there's not much functional change but quite a bit of modernization going on. We've also seen a lot of driver work, a lot of it cleanups but also some particular drivers. - Lots and lots of cleanups from Morimoto-san and Yue Haibing. - Lots of cleanups and enhancements to the Freescale, sunxi dnd Intel rivers. - Initial Sound Open Firmware suppot for i.MX8. - Removal of w90x900 and nuc900 drivers as the platforms are being removed. - New support for Cirrus Logic CS47L15 and CS47L92, Freescale i.MX 7ULP and 8MQ, Meson G12A and NXP UDA1334
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+MPIC interrupt controller
+=========================
+
+Device types supported:
+ KVM_DEV_TYPE_FSL_MPIC_20 Freescale MPIC v2.0
+ KVM_DEV_TYPE_FSL_MPIC_42 Freescale MPIC v4.2
+
+Only one MPIC instance, of any type, may be instantiated. The created
+MPIC will act as the system interrupt controller, connecting to each
+vcpu's interrupt inputs.
+
+Groups:
+ KVM_DEV_MPIC_GRP_MISC
+ Attributes:
+ KVM_DEV_MPIC_BASE_ADDR (rw, 64-bit)
+ Base address of the 256 KiB MPIC register space. Must be
+ naturally aligned. A value of zero disables the mapping.
+ Reset value is zero.
+
+ KVM_DEV_MPIC_GRP_REGISTER (rw, 32-bit)
+ Access an MPIC register, as if the access were made from the guest.
+ "attr" is the byte offset into the MPIC register space. Accesses
+ must be 4-byte aligned.
+
+ MSIs may be signaled by using this attribute group to write
+ to the relevant MSIIR.
+
+ KVM_DEV_MPIC_GRP_IRQ_ACTIVE (rw, 32-bit)
+ IRQ input line for each standard openpic source. 0 is inactive and 1
+ is active, regardless of interrupt sense.
+
+ For edge-triggered interrupts: Writing 1 is considered an activating
+ edge, and writing 0 is ignored. Reading returns 1 if a previously
+ signaled edge has not been acknowledged, and 0 otherwise.
+
+ "attr" is the IRQ number. IRQ numbers for standard sources are the
+ byte offset of the relevant IVPR from EIVPR0, divided by 32.
+
+IRQ Routing:
+
+ The MPIC emulation supports IRQ routing. Only a single MPIC device can
+ be instantiated. Once that device has been created, it's available as
+ irqchip id 0.
+
+ This irqchip 0 has 256 interrupt pins, which expose the interrupts in
+ the main array of interrupt sources (a.k.a. "SRC" interrupts).
+
+ The numbering is the same as the MPIC device tree binding -- based on
+ the register offset from the beginning of the sources array, without
+ regard to any subdivisions in chip documentation such as "internal"
+ or "external" interrupts.
+
+ Access to non-SRC interrupts is not implemented through IRQ routing mechanisms.