kernel/drivers/misc/cxl/base.c, branch linux-5.1.y

Revert "cxl: Allow a default context to be associated with an external pci_dev"

2018-07-02T13:54:33Z

Remove abandonned capi support for the Mellanox CX4. This reverts commit a19bd79e31769626d288cc016e21a31b6f47bf6f. Signed-off-by: Frederic Barrat Acked-by: Andrew Donnellan Signed-off-by: Michael Ellerman

Revert "cxl: Add preliminary workaround for CX4 interrupt limitation"

2018-07-02T13:54:31Z

Remove abandonned capi support for the Mellanox CX4. This reverts commit cbce0917e2e47d4bf5aa3b5fd6b1247f33e1a126. Signed-off-by: Alastair D'Silva Acked-by: Andrew Donnellan Signed-off-by: Michael Ellerman

Revert "cxl: Add support for interrupts on the Mellanox CX4"

2018-07-02T13:54:30Z

Remove abandonned capi support for the Mellanox CX4. This reverts commit a2f67d5ee8d950caaa7a6144cf0bfb256500b73e. Signed-off-by: Alastair D'Silva Acked-by: Andrew Donnellan Signed-off-by: Michael Ellerman

cxl: Add support for interrupts on the Mellanox CX4

2016-07-14T10:27:08Z

The Mellanox CX4 in cxl mode uses a hybrid interrupt model, where interrupts are routed from the networking hardware to the XSL using the MSIX table, and from there will be transformed back into an MSIX interrupt using the cxl style interrupts (i.e. using IVTE entries and ranges to map a PE and AFU interrupt number to an MSIX address). We want to hide the implementation details of cxl interrupts as much as possible. To this end, we use a special version of the MSI setup & teardown routines in the PHB while in cxl mode to allocate the cxl interrupts and configure the IVTE entries in the process element. This function does not configure the MSIX table - the CX4 card uses a custom format in that table and it would not be appropriate to fill that out in generic code. The rest of the functionality is similar to the "Full MSI-X mode" described in the CAIA, and this could be easily extended to support other adapters that use that mode in the future. The interrupts will be associated with the default context. If the maximum number of interrupts per context has been limited (e.g. by the mlx5 driver), it will automatically allocate additional kernel contexts to associate extra interrupts as required. These contexts will be started using the same WED that was used to start the default context. Signed-off-by: Ian Munsie Reviewed-by: Andrew Donnellan Signed-off-by: Michael Ellerman

cxl: Add preliminary workaround for CX4 interrupt limitation

2016-07-14T10:27:02Z

The Mellanox CX4 has a hardware limitation where only 4 bits of the AFU interrupt number can be passed to the XSL when sending an interrupt, limiting it to only 15 interrupts per context (AFU interrupt number 0 is invalid). In order to overcome this, we will allocate additional contexts linked to the default context as extra address space for the extra interrupts - this will be implemented in the next patch. This patch adds the preliminary support to allow this, by way of adding a linked list in the context structure that we use to keep track of the contexts dedicated to interrupts, and an API to simultaneously iterate over the related context structures, AFU interrupt numbers and hardware interrupt numbers. The point of using a single API to iterate these is to hide some of the details of the iteration from external code, and to reduce the number of APIs that need to be exported via base.c to allow built in code to call. Signed-off-by: Ian Munsie Reviewed-by: Frederic Barrat Reviewed-by: Andrew Donnellan Signed-off-by: Michael Ellerman

cxl: Allow a default context to be associated with an external pci_dev

2016-07-14T10:26:52Z

The cxl kernel API has a concept of a default context associated with each PCI device under the virtual PHB. The Mellanox CX4 will also use the cxl kernel API, but it does not use a virtual PHB - rather, the AFU appears as a physical function as a peer to the networking functions. In order to allow the kernel API to work with those networking functions, we will need to associate a default context with them as well. To this end, refactor the corresponding code to do this in vphb.c and export it so that it can be called from the PHB code. Signed-off-by: Ian Munsie Reviewed-by: Frederic Barrat Reviewed-by: Andrew Donnellan Signed-off-by: Michael Ellerman

cxl: Move cxl_afu_get / cxl_afu_put to base

2016-07-14T10:26:36Z

The Mellanox CX4 uses a model where the AFU is one physical function of the device, and is used by other peer physical functions of the same device. This will require those other devices to grab a reference on the AFU when they are initialised to make sure that it does not go away during their lifetime. Move the AFU refcount functions to base.c so they can be called from the PHB code. Signed-off-by: Ian Munsie Reviewed-by: Andrew Donnellan Reviewed-by: Frederic Barrat Signed-off-by: Michael Ellerman

cxl: Use for_each_compatible_node() macro

2016-07-14T10:26:25Z

Use for_each_compatible_node() macro instead of open coding it. Generated by Coccinelle. Signed-off-by: Wei Yongjun Reviewed-by: Andrew Donnellan Acked-by: Ian Munsie Signed-off-by: Michael Ellerman

cxl: make base more explicitly non-modular

2016-07-08T12:22:58Z

The Kconfig/Makefile currently controlling compilation of this code is: drivers/misc/cxl/Kconfig:config CXL_BASE drivers/misc/cxl/Kconfig: bool drivers/misc/cxl/Makefile:obj-$(CONFIG_CXL_BASE) += base.o ...meaning that it currently is not being built as a module by anyone. Lets convert the one module_init into device_initcall so that when reading the driver it more clear that it is builtin-only. Since module_init translates to device_initcall in the non-modular case, the init ordering remains unchanged with this commit. We don't replace module.h with init.h since the file is doing other modular stuff (module_get/put) even though it is built-in. Cc: Ian Munsie Cc: Michael Neuling Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Paul Gortmaker Acked-by: Ian Munsie Signed-off-by: Michael Ellerman

cxl: Parse device tree and create cxl device(s) at boot

2016-03-09T12:39:59Z

Add new entry point to scan the device tree at boot in a guest, looking for cxl devices. Co-authored-by: Christophe Lombard Signed-off-by: Frederic Barrat Signed-off-by: Christophe Lombard Reviewed-by: Manoj Kumar Acked-by: Ian Munsie Signed-off-by: Michael Ellerman