qemu-e2k/include/hw/cxl/cxl.h

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hw/cxl/component: Introduce CXL components (8.1.x, 8.2.5) A CXL 2.0 component is any entity in the CXL topology. All components have a analogous function in PCIe. Except for the CXL host bridge, all have a PCIe config space that is accessible via the common PCIe mechanisms. CXL components are enumerated via DVSEC fields in the extended PCIe header space. CXL components will minimally implement some subset of CXL.mem and CXL.cache registers defined in 8.2.5 of the CXL 2.0 specification. Two headers and a utility library are introduced to support the minimum functionality needed to enumerate components. The cxl_pci header manages bits associated with PCI, specifically the DVSEC and related fields. The cxl_component.h variant has data structures and APIs that are useful for drivers implementing any of the CXL 2.0 components. The library takes care of making use of the DVSEC bits and the CXL.[mem|cache] registers. Per spec, the registers are little endian. None of the mechanisms required to enumerate a CXL capable hostbridge are introduced at this point. Note that the CXL.mem and CXL.cache registers used are always 4B wide. It's possible in the future that this constraint will not hold. Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Adam Manzanares <a.manzanares@samsung.com> Message-Id: <20220429144110.25167-3-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:27 +02:00
/*
* QEMU CXL Support
*
* Copyright (c) 2020 Intel
*
* This work is licensed under the terms of the GNU GPL, version 2. See the
* COPYING file in the top-level directory.
*/
#ifndef CXL_H
#define CXL_H
hw/cxl/host: Add support for CXL Fixed Memory Windows. The concept of these is introduced in [1] in terms of the description the CEDT ACPI table. The principal is more general. Unlike once traffic hits the CXL root bridges, the host system memory address routing is implementation defined and effectively static once observable by standard / generic system software. Each CXL Fixed Memory Windows (CFMW) is a region of PA space which has fixed system dependent routing configured so that accesses can be routed to the CXL devices below a set of target root bridges. The accesses may be interleaved across multiple root bridges. For QEMU we could have fully specified these regions in terms of a base PA + size, but as the absolute address does not matter it is simpler to let individual platforms place the memory regions. ExampleS: -cxl-fixed-memory-window targets.0=cxl.0,size=128G -cxl-fixed-memory-window targets.0=cxl.1,size=128G -cxl-fixed-memory-window targets.0=cxl0,targets.1=cxl.1,size=256G,interleave-granularity=2k Specifies * 2x 128G regions not interleaved across root bridges, one for each of the root bridges with ids cxl.0 and cxl.1 * 256G region interleaved across root bridges with ids cxl.0 and cxl.1 with a 2k interleave granularity. When system software enumerates the devices below a given root bridge it can then decide which CFMW to use. If non interleave is desired (or possible) it can use the appropriate CFMW for the root bridge in question. If there are suitable devices to interleave across the two root bridges then it may use the 3rd CFMS. A number of other designs were considered but the following constraints made it hard to adapt existing QEMU approaches to this particular problem. 1) The size must be known before a specific architecture / board brings up it's PA memory map. We need to set up an appropriate region. 2) Using links to the host bridges provides a clean command line interface but these links cannot be established until command line devices have been added. Hence the two step process used here of first establishing the size, interleave-ways and granularity + caching the ids of the host bridges and then, once available finding the actual host bridges so they can be used later to support interleave decoding. [1] CXL 2.0 ECN: CEDT CFMWS & QTG DSM (computeexpresslink.org / specifications) Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com> Acked-by: Markus Armbruster <armbru@redhat.com> # QAPI Schema Message-Id: <20220429144110.25167-28-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:52 +02:00
#include "qapi/qapi-types-machine.h"
#include "qapi/qapi-visit-machine.h"
hw/cxl/host: Add support for CXL Fixed Memory Windows. The concept of these is introduced in [1] in terms of the description the CEDT ACPI table. The principal is more general. Unlike once traffic hits the CXL root bridges, the host system memory address routing is implementation defined and effectively static once observable by standard / generic system software. Each CXL Fixed Memory Windows (CFMW) is a region of PA space which has fixed system dependent routing configured so that accesses can be routed to the CXL devices below a set of target root bridges. The accesses may be interleaved across multiple root bridges. For QEMU we could have fully specified these regions in terms of a base PA + size, but as the absolute address does not matter it is simpler to let individual platforms place the memory regions. ExampleS: -cxl-fixed-memory-window targets.0=cxl.0,size=128G -cxl-fixed-memory-window targets.0=cxl.1,size=128G -cxl-fixed-memory-window targets.0=cxl0,targets.1=cxl.1,size=256G,interleave-granularity=2k Specifies * 2x 128G regions not interleaved across root bridges, one for each of the root bridges with ids cxl.0 and cxl.1 * 256G region interleaved across root bridges with ids cxl.0 and cxl.1 with a 2k interleave granularity. When system software enumerates the devices below a given root bridge it can then decide which CFMW to use. If non interleave is desired (or possible) it can use the appropriate CFMW for the root bridge in question. If there are suitable devices to interleave across the two root bridges then it may use the 3rd CFMS. A number of other designs were considered but the following constraints made it hard to adapt existing QEMU approaches to this particular problem. 1) The size must be known before a specific architecture / board brings up it's PA memory map. We need to set up an appropriate region. 2) Using links to the host bridges provides a clean command line interface but these links cannot be established until command line devices have been added. Hence the two step process used here of first establishing the size, interleave-ways and granularity + caching the ids of the host bridges and then, once available finding the actual host bridges so they can be used later to support interleave decoding. [1] CXL 2.0 ECN: CEDT CFMWS & QTG DSM (computeexpresslink.org / specifications) Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com> Acked-by: Markus Armbruster <armbru@redhat.com> # QAPI Schema Message-Id: <20220429144110.25167-28-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:52 +02:00
#include "hw/pci/pci_bridge.h"
#include "hw/pci/pci_host.h"
hw/cxl/component: Introduce CXL components (8.1.x, 8.2.5) A CXL 2.0 component is any entity in the CXL topology. All components have a analogous function in PCIe. Except for the CXL host bridge, all have a PCIe config space that is accessible via the common PCIe mechanisms. CXL components are enumerated via DVSEC fields in the extended PCIe header space. CXL components will minimally implement some subset of CXL.mem and CXL.cache registers defined in 8.2.5 of the CXL 2.0 specification. Two headers and a utility library are introduced to support the minimum functionality needed to enumerate components. The cxl_pci header manages bits associated with PCI, specifically the DVSEC and related fields. The cxl_component.h variant has data structures and APIs that are useful for drivers implementing any of the CXL 2.0 components. The library takes care of making use of the DVSEC bits and the CXL.[mem|cache] registers. Per spec, the registers are little endian. None of the mechanisms required to enumerate a CXL capable hostbridge are introduced at this point. Note that the CXL.mem and CXL.cache registers used are always 4B wide. It's possible in the future that this constraint will not hold. Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Adam Manzanares <a.manzanares@samsung.com> Message-Id: <20220429144110.25167-3-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:27 +02:00
#include "cxl_pci.h"
#include "cxl_component.h"
#include "cxl_device.h"
hw/cxl/component: Introduce CXL components (8.1.x, 8.2.5) A CXL 2.0 component is any entity in the CXL topology. All components have a analogous function in PCIe. Except for the CXL host bridge, all have a PCIe config space that is accessible via the common PCIe mechanisms. CXL components are enumerated via DVSEC fields in the extended PCIe header space. CXL components will minimally implement some subset of CXL.mem and CXL.cache registers defined in 8.2.5 of the CXL 2.0 specification. Two headers and a utility library are introduced to support the minimum functionality needed to enumerate components. The cxl_pci header manages bits associated with PCI, specifically the DVSEC and related fields. The cxl_component.h variant has data structures and APIs that are useful for drivers implementing any of the CXL 2.0 components. The library takes care of making use of the DVSEC bits and the CXL.[mem|cache] registers. Per spec, the registers are little endian. None of the mechanisms required to enumerate a CXL capable hostbridge are introduced at this point. Note that the CXL.mem and CXL.cache registers used are always 4B wide. It's possible in the future that this constraint will not hold. Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Adam Manzanares <a.manzanares@samsung.com> Message-Id: <20220429144110.25167-3-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:27 +02:00
#define CXL_COMPONENT_REG_BAR_IDX 0
#define CXL_DEVICE_REG_BAR_IDX 2
#define CXL_WINDOW_MAX 10
hw/cxl/host: Add support for CXL Fixed Memory Windows. The concept of these is introduced in [1] in terms of the description the CEDT ACPI table. The principal is more general. Unlike once traffic hits the CXL root bridges, the host system memory address routing is implementation defined and effectively static once observable by standard / generic system software. Each CXL Fixed Memory Windows (CFMW) is a region of PA space which has fixed system dependent routing configured so that accesses can be routed to the CXL devices below a set of target root bridges. The accesses may be interleaved across multiple root bridges. For QEMU we could have fully specified these regions in terms of a base PA + size, but as the absolute address does not matter it is simpler to let individual platforms place the memory regions. ExampleS: -cxl-fixed-memory-window targets.0=cxl.0,size=128G -cxl-fixed-memory-window targets.0=cxl.1,size=128G -cxl-fixed-memory-window targets.0=cxl0,targets.1=cxl.1,size=256G,interleave-granularity=2k Specifies * 2x 128G regions not interleaved across root bridges, one for each of the root bridges with ids cxl.0 and cxl.1 * 256G region interleaved across root bridges with ids cxl.0 and cxl.1 with a 2k interleave granularity. When system software enumerates the devices below a given root bridge it can then decide which CFMW to use. If non interleave is desired (or possible) it can use the appropriate CFMW for the root bridge in question. If there are suitable devices to interleave across the two root bridges then it may use the 3rd CFMS. A number of other designs were considered but the following constraints made it hard to adapt existing QEMU approaches to this particular problem. 1) The size must be known before a specific architecture / board brings up it's PA memory map. We need to set up an appropriate region. 2) Using links to the host bridges provides a clean command line interface but these links cannot be established until command line devices have been added. Hence the two step process used here of first establishing the size, interleave-ways and granularity + caching the ids of the host bridges and then, once available finding the actual host bridges so they can be used later to support interleave decoding. [1] CXL 2.0 ECN: CEDT CFMWS & QTG DSM (computeexpresslink.org / specifications) Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com> Acked-by: Markus Armbruster <armbru@redhat.com> # QAPI Schema Message-Id: <20220429144110.25167-28-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:52 +02:00
typedef struct CXLFixedWindow {
uint64_t size;
char **targets;
struct PXBDev *target_hbs[8];
uint8_t num_targets;
uint8_t enc_int_ways;
uint8_t enc_int_gran;
/* Todo: XOR based interleaving */
MemoryRegion mr;
hwaddr base;
} CXLFixedWindow;
typedef struct CXLState {
bool is_enabled;
MemoryRegion host_mr;
unsigned int next_mr_idx;
hw/cxl/host: Add support for CXL Fixed Memory Windows. The concept of these is introduced in [1] in terms of the description the CEDT ACPI table. The principal is more general. Unlike once traffic hits the CXL root bridges, the host system memory address routing is implementation defined and effectively static once observable by standard / generic system software. Each CXL Fixed Memory Windows (CFMW) is a region of PA space which has fixed system dependent routing configured so that accesses can be routed to the CXL devices below a set of target root bridges. The accesses may be interleaved across multiple root bridges. For QEMU we could have fully specified these regions in terms of a base PA + size, but as the absolute address does not matter it is simpler to let individual platforms place the memory regions. ExampleS: -cxl-fixed-memory-window targets.0=cxl.0,size=128G -cxl-fixed-memory-window targets.0=cxl.1,size=128G -cxl-fixed-memory-window targets.0=cxl0,targets.1=cxl.1,size=256G,interleave-granularity=2k Specifies * 2x 128G regions not interleaved across root bridges, one for each of the root bridges with ids cxl.0 and cxl.1 * 256G region interleaved across root bridges with ids cxl.0 and cxl.1 with a 2k interleave granularity. When system software enumerates the devices below a given root bridge it can then decide which CFMW to use. If non interleave is desired (or possible) it can use the appropriate CFMW for the root bridge in question. If there are suitable devices to interleave across the two root bridges then it may use the 3rd CFMS. A number of other designs were considered but the following constraints made it hard to adapt existing QEMU approaches to this particular problem. 1) The size must be known before a specific architecture / board brings up it's PA memory map. We need to set up an appropriate region. 2) Using links to the host bridges provides a clean command line interface but these links cannot be established until command line devices have been added. Hence the two step process used here of first establishing the size, interleave-ways and granularity + caching the ids of the host bridges and then, once available finding the actual host bridges so they can be used later to support interleave decoding. [1] CXL 2.0 ECN: CEDT CFMWS & QTG DSM (computeexpresslink.org / specifications) Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com> Acked-by: Markus Armbruster <armbru@redhat.com> # QAPI Schema Message-Id: <20220429144110.25167-28-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:52 +02:00
GList *fixed_windows;
CXLFixedMemoryWindowOptionsList *cfmw_list;
} CXLState;
struct CXLHost {
PCIHostState parent_obj;
CXLComponentState cxl_cstate;
};
#define TYPE_PXB_CXL_HOST "pxb-cxl-host"
OBJECT_DECLARE_SIMPLE_TYPE(CXLHost, PXB_CXL_HOST)
#define TYPE_CXL_USP "cxl-upstream"
typedef struct CXLUpstreamPort CXLUpstreamPort;
DECLARE_INSTANCE_CHECKER(CXLUpstreamPort, CXL_USP, TYPE_CXL_USP)
CXLComponentState *cxl_usp_to_cstate(CXLUpstreamPort *usp);
hw/cxl/component: Introduce CXL components (8.1.x, 8.2.5) A CXL 2.0 component is any entity in the CXL topology. All components have a analogous function in PCIe. Except for the CXL host bridge, all have a PCIe config space that is accessible via the common PCIe mechanisms. CXL components are enumerated via DVSEC fields in the extended PCIe header space. CXL components will minimally implement some subset of CXL.mem and CXL.cache registers defined in 8.2.5 of the CXL 2.0 specification. Two headers and a utility library are introduced to support the minimum functionality needed to enumerate components. The cxl_pci header manages bits associated with PCI, specifically the DVSEC and related fields. The cxl_component.h variant has data structures and APIs that are useful for drivers implementing any of the CXL 2.0 components. The library takes care of making use of the DVSEC bits and the CXL.[mem|cache] registers. Per spec, the registers are little endian. None of the mechanisms required to enumerate a CXL capable hostbridge are introduced at this point. Note that the CXL.mem and CXL.cache registers used are always 4B wide. It's possible in the future that this constraint will not hold. Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Adam Manzanares <a.manzanares@samsung.com> Message-Id: <20220429144110.25167-3-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-04-29 16:40:27 +02:00
#endif