From: "J. Neuschäfer" <j...@posteo.net> As part of a larger effort to bring various PowerPC-related bindings into the YAML world, this patch converts msi-pic.txt to YAML and moves it into the bindings/interrupt-controller/ directory. The conversion may necessarily be a bit hard to read because the binding is quite verbose.
Signed-off-by: J. Neuschäfer <j...@posteo.net> --- .../interrupt-controller/fsl,mpic-msi.yaml | 141 +++++++++++++++++++++ .../devicetree/bindings/powerpc/fsl/msi-pic.txt | 111 ---------------- 2 files changed, 141 insertions(+), 111 deletions(-) diff --git a/Documentation/devicetree/bindings/interrupt-controller/fsl,mpic-msi.yaml b/Documentation/devicetree/bindings/interrupt-controller/fsl,mpic-msi.yaml new file mode 100644 index 0000000000000000000000000000000000000000..99a98864bd10c5e5b67112c0149fe123b51ca26f --- /dev/null +++ b/Documentation/devicetree/bindings/interrupt-controller/fsl,mpic-msi.yaml @@ -0,0 +1,141 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/interrupt-controller/fsl,mpic-msi.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Freescale MSI interrupt controller + +description: + The Freescale hypervisor and msi-address-64 + ------------------------------------------- + + Normally, PCI devices have access to all of CCSR via an ATMU mapping. The + Freescale MSI driver calculates the address of MSIIR (in the MSI register + block) and sets that address as the MSI message address. + + In a virtualized environment, the hypervisor may need to create an IOMMU + mapping for MSIIR. The Freescale ePAPR hypervisor has this requirement + because of hardware limitations of the Peripheral Access Management Unit + (PAMU), which is currently the only IOMMU that the hypervisor supports. + The ATMU is programmed with the guest physical address, and the PAMU + intercepts transactions and reroutes them to the true physical address. + + In the PAMU, each PCI controller is given only one primary window. The + PAMU restricts DMA operations so that they can only occur within a window. + Because PCI devices must be able to DMA to memory, the primary window must + be used to cover all of the guest's memory space. + + PAMU primary windows can be divided into 256 subwindows, and each + subwindow can have its own address mapping ("guest physical" to "true + physical"). However, each subwindow has to have the same alignment, which + means they cannot be located at just any address. Because of these + restrictions, it is usually impossible to create a 4KB subwindow that + covers MSIIR where it's normally located. + + Therefore, the hypervisor has to create a subwindow inside the same + primary window used for memory, but mapped to the MSIR block (where MSIIR + lives). The first subwindow after the end of guest memory is used for + this. The address specified in the msi-address-64 property is the PCI + address of MSIIR. The hypervisor configures the PAMU to map that address to + the true physical address of MSIIR. + +maintainers: + - J. Neuschäfer <j...@posteo.net> + +properties: + compatible: + oneOf: + - enum: + - fsl,mpic-msi + - fsl,mpic-msi-v4.3 + - fsl,ipic-msi + - fsl,vmpic-msi + - fsl,vmpic-msi-v4.3 + - items: + - enum: + - fsl,mpc8572-msi + - fsl,mpc8610-msi + - fsl,mpc8641-msi + - const: fsl,mpic-msi + description: + compatible list, may contain one or two entries The first is + "fsl,CHIP-msi", where CHIP is the processor(mpc8610, mpc8572, etc.) and + the second is "fsl,mpic-msi" or "fsl,ipic-msi" or "fsl,mpic-msi-v4.3" + depending on the parent type and version. If mpic version is 4.3, the + number of MSI registers is increased to 16, MSIIR1 is provided to access + these 16 registers, and compatible "fsl,mpic-msi-v4.3" should be used. + The first entry is optional; the second entry is required. + + reg: + minItems: 1 + items: + - description: Address and length of the shared message interrupt + register set + - description: Address of aliased MSIIR or MSIIR1 register for platforms + that have such an alias. If using MSIIR1, the second region must be + added because different MSI group has different MSIIR1 offset. + + interrupts: + minItems: 1 + maxItems: 16 + description: + Each one of the interrupts here is one entry per 32 MSIs, and routed to + the host interrupt controller. The interrupts should be set as edge + sensitive. If msi-available-ranges is present, only the interrupts that + correspond to available ranges shall be present. + + msi-available-ranges: + $ref: /schemas/types.yaml#/definitions/uint32-matrix + items: + items: + - description: First MSI interrupt in this range + - description: Number of MSI interrupts in this range + description: + Use <start count> style section to define which MSI interrupt can be used + in the 256 msi interrupts. This property is optional, without this, all + the MSI interrupts can be used. Each available range must begin and end + on a multiple of 32 (i.e. no splitting an individual MSI register or the + associated PIC interrupt). MPIC v4.3 does not support this property + because the 32 interrupts of an individual register are not continuous + when using MSIIR1. + + msi-address-64: + $ref: /schemas/types.yaml#/definitions/uint64 + description: + 64-bit PCI address of the MSIIR register. The MSIIR register is used for + MSI messaging. The address of MSIIR in PCI address space is the MSI + message address. + + This property may be used in virtualized environments where the hypervisor + has created an alternate mapping for the MSIR block. See the top-level + description for an explanation. + +required: + - compatible + - reg + - interrupts + +unevaluatedProperties: false + +examples: + - | + msi@41600 { + compatible = "fsl,mpc8610-msi", "fsl,mpic-msi"; + reg = <0x41600 0x80>; + msi-available-ranges = <0 0x100>; + interrupts = <0xe0 0>, <0xe1 0>, <0xe2 0>, <0xe3 0>, + <0xe4 0>, <0xe5 0>, <0xe6 0>, <0xe7 0>; + }; + + - | + msi@41600 { + compatible = "fsl,mpic-msi-v4.3"; + reg = <0x41600 0x200 0x44148 4>; + interrupts = <0xe0 0 0 0>, <0xe1 0 0 0>, <0xe2 0 0 0>, <0xe3 0 0 0>, + <0xe4 0 0 0>, <0xe5 0 0 0>, <0xe6 0 0 0>, <0xe7 0 0 0>, + <0x100 0 0 0>, <0x101 0 0 0>, <0x102 0 0 0>, <0x103 0 0 0>, + <0x104 0 0 0>, <0x105 0 0 0>, <0x106 0 0 0>, <0x107 0 0 0>; + }; + +... diff --git a/Documentation/devicetree/bindings/powerpc/fsl/msi-pic.txt b/Documentation/devicetree/bindings/powerpc/fsl/msi-pic.txt deleted file mode 100644 index f8d2b7fe06d695971d48ba21ab67e5b72a212fe9..0000000000000000000000000000000000000000 --- a/Documentation/devicetree/bindings/powerpc/fsl/msi-pic.txt +++ /dev/null @@ -1,111 +0,0 @@ -* Freescale MSI interrupt controller - -Required properties: -- compatible : compatible list, may contain one or two entries - The first is "fsl,CHIP-msi", where CHIP is the processor(mpc8610, mpc8572, - etc.) and the second is "fsl,mpic-msi" or "fsl,ipic-msi" or - "fsl,mpic-msi-v4.3" depending on the parent type and version. If mpic - version is 4.3, the number of MSI registers is increased to 16, MSIIR1 is - provided to access these 16 registers, and compatible "fsl,mpic-msi-v4.3" - should be used. The first entry is optional; the second entry is - required. - -- reg : It may contain one or two regions. The first region should contain - the address and the length of the shared message interrupt register set. - The second region should contain the address of aliased MSIIR or MSIIR1 - register for platforms that have such an alias, if using MSIIR1, the second - region must be added because different MSI group has different MSIIR1 offset. - -- interrupts : each one of the interrupts here is one entry per 32 MSIs, - and routed to the host interrupt controller. the interrupts should - be set as edge sensitive. If msi-available-ranges is present, only - the interrupts that correspond to available ranges shall be present. - -Optional properties: -- msi-available-ranges: use <start count> style section to define which - msi interrupt can be used in the 256 msi interrupts. This property is - optional, without this, all the MSI interrupts can be used. - Each available range must begin and end on a multiple of 32 (i.e. - no splitting an individual MSI register or the associated PIC interrupt). - MPIC v4.3 does not support this property because the 32 interrupts of an - individual register are not continuous when using MSIIR1. - -- msi-address-64: 64-bit PCI address of the MSIIR register. The MSIIR register - is used for MSI messaging. The address of MSIIR in PCI address space is - the MSI message address. - - This property may be used in virtualized environments where the hypervisor - has created an alternate mapping for the MSIR block. See below for an - explanation. - - -Example: - msi@41600 { - compatible = "fsl,mpc8610-msi", "fsl,mpic-msi"; - reg = <0x41600 0x80>; - msi-available-ranges = <0 0x100>; - interrupts = < - 0xe0 0 - 0xe1 0 - 0xe2 0 - 0xe3 0 - 0xe4 0 - 0xe5 0 - 0xe6 0 - 0xe7 0>; - interrupt-parent = <&mpic>; - }; - - msi@41600 { - compatible = "fsl,mpic-msi-v4.3"; - reg = <0x41600 0x200 0x44148 4>; - interrupts = < - 0xe0 0 0 0 - 0xe1 0 0 0 - 0xe2 0 0 0 - 0xe3 0 0 0 - 0xe4 0 0 0 - 0xe5 0 0 0 - 0xe6 0 0 0 - 0xe7 0 0 0 - 0x100 0 0 0 - 0x101 0 0 0 - 0x102 0 0 0 - 0x103 0 0 0 - 0x104 0 0 0 - 0x105 0 0 0 - 0x106 0 0 0 - 0x107 0 0 0>; - }; - -The Freescale hypervisor and msi-address-64 -------------------------------------------- -Normally, PCI devices have access to all of CCSR via an ATMU mapping. The -Freescale MSI driver calculates the address of MSIIR (in the MSI register -block) and sets that address as the MSI message address. - -In a virtualized environment, the hypervisor may need to create an IOMMU -mapping for MSIIR. The Freescale ePAPR hypervisor has this requirement -because of hardware limitations of the Peripheral Access Management Unit -(PAMU), which is currently the only IOMMU that the hypervisor supports. -The ATMU is programmed with the guest physical address, and the PAMU -intercepts transactions and reroutes them to the true physical address. - -In the PAMU, each PCI controller is given only one primary window. The -PAMU restricts DMA operations so that they can only occur within a window. -Because PCI devices must be able to DMA to memory, the primary window must -be used to cover all of the guest's memory space. - -PAMU primary windows can be divided into 256 subwindows, and each -subwindow can have its own address mapping ("guest physical" to "true -physical"). However, each subwindow has to have the same alignment, which -means they cannot be located at just any address. Because of these -restrictions, it is usually impossible to create a 4KB subwindow that -covers MSIIR where it's normally located. - -Therefore, the hypervisor has to create a subwindow inside the same -primary window used for memory, but mapped to the MSIR block (where MSIIR -lives). The first subwindow after the end of guest memory is used for -this. The address specified in the msi-address-64 property is the PCI -address of MSIIR. The hypervisor configures the PAMU to map that address to -the true physical address of MSIIR. --- base-commit: 2014c95afecee3e76ca4a56956a936e23283f05b change-id: 20250226-msipic-yaml-76e3f00bf5ee Best regards, -- J. Neuschäfer <j...@posteo.net>
