linux/drivers/cxl/cxl.h
Nathan Chancellor be185c2988 cxl/core: Remove cxld_const_init in cxl_decoder_alloc()
Commit 48667f6761 ("cxl/core: Split decoder setup into alloc + add")
aimed to fix a large stack frame warning but from v5 to v6, it
introduced a new instance of the warning due to allocating
cxld_const_init on the stack, which was done due to the use of const on
the nr_target member of the cxl_decoder struct. With ARCH=arm
allmodconfig minus CONFIG_KASAN:

GCC 11.2.0:

drivers/cxl/core/bus.c: In function ‘cxl_decoder_alloc’:
drivers/cxl/core/bus.c:523:1: error: the frame size of 1032 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
  523 | }
      | ^
cc1: all warnings being treated as errors

Clang 12.0.1:

drivers/cxl/core/bus.c:486:21: error: stack frame size of 1056 bytes in function 'cxl_decoder_alloc' [-Werror,-Wframe-larger-than=]
struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets)
                    ^
1 error generated.

Revert that part of the change, which makes the stack frame of
cxl_decoder_alloc() much more reasonable.

Fixes: 48667f6761 ("cxl/core: Split decoder setup into alloc + add")
Link: https://github.com/ClangBuiltLinux/linux/issues/1539
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20211210213627.2477370-1-nathan@kernel.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-01-04 17:29:31 -08:00

330 lines
10 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/* Copyright(c) 2020 Intel Corporation. */
#ifndef __CXL_H__
#define __CXL_H__
#include <linux/libnvdimm.h>
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/io.h>
/**
* DOC: cxl objects
*
* The CXL core objects like ports, decoders, and regions are shared
* between the subsystem drivers cxl_acpi, cxl_pci, and core drivers
* (port-driver, region-driver, nvdimm object-drivers... etc).
*/
/* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/
#define CXL_CM_OFFSET 0x1000
#define CXL_CM_CAP_HDR_OFFSET 0x0
#define CXL_CM_CAP_HDR_ID_MASK GENMASK(15, 0)
#define CM_CAP_HDR_CAP_ID 1
#define CXL_CM_CAP_HDR_VERSION_MASK GENMASK(19, 16)
#define CM_CAP_HDR_CAP_VERSION 1
#define CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK GENMASK(23, 20)
#define CM_CAP_HDR_CACHE_MEM_VERSION 1
#define CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24)
#define CXL_CM_CAP_PTR_MASK GENMASK(31, 20)
#define CXL_CM_CAP_CAP_ID_HDM 0x5
#define CXL_CM_CAP_CAP_HDM_VERSION 1
/* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
#define CXL_HDM_DECODER_CAP_OFFSET 0x0
#define CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
#define CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
#define CXL_HDM_DECODER0_BASE_LOW_OFFSET 0x10
#define CXL_HDM_DECODER0_BASE_HIGH_OFFSET 0x14
#define CXL_HDM_DECODER0_SIZE_LOW_OFFSET 0x18
#define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET 0x1c
#define CXL_HDM_DECODER0_CTRL_OFFSET 0x20
static inline int cxl_hdm_decoder_count(u32 cap_hdr)
{
int val = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, cap_hdr);
return val ? val * 2 : 1;
}
/* CXL 2.0 8.2.8.1 Device Capabilities Array Register */
#define CXLDEV_CAP_ARRAY_OFFSET 0x0
#define CXLDEV_CAP_ARRAY_CAP_ID 0
#define CXLDEV_CAP_ARRAY_ID_MASK GENMASK_ULL(15, 0)
#define CXLDEV_CAP_ARRAY_COUNT_MASK GENMASK_ULL(47, 32)
/* CXL 2.0 8.2.8.2 CXL Device Capability Header Register */
#define CXLDEV_CAP_HDR_CAP_ID_MASK GENMASK(15, 0)
/* CXL 2.0 8.2.8.2.1 CXL Device Capabilities */
#define CXLDEV_CAP_CAP_ID_DEVICE_STATUS 0x1
#define CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX 0x2
#define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
#define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
/* CXL 2.0 8.2.8.4 Mailbox Registers */
#define CXLDEV_MBOX_CAPS_OFFSET 0x00
#define CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
#define CXLDEV_MBOX_CTRL_OFFSET 0x04
#define CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
#define CXLDEV_MBOX_CMD_OFFSET 0x08
#define CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
#define CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
#define CXLDEV_MBOX_STATUS_OFFSET 0x10
#define CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
#define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
#define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
/*
* Using struct_group() allows for per register-block-type helper routines,
* without requiring block-type agnostic code to include the prefix.
*/
struct cxl_regs {
/*
* Common set of CXL Component register block base pointers
* @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
*/
struct_group_tagged(cxl_component_regs, component,
void __iomem *hdm_decoder;
);
/*
* Common set of CXL Device register block base pointers
* @status: CXL 2.0 8.2.8.3 Device Status Registers
* @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
* @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
*/
struct_group_tagged(cxl_device_regs, device_regs,
void __iomem *status, *mbox, *memdev;
);
};
struct cxl_reg_map {
bool valid;
unsigned long offset;
unsigned long size;
};
struct cxl_component_reg_map {
struct cxl_reg_map hdm_decoder;
};
struct cxl_device_reg_map {
struct cxl_reg_map status;
struct cxl_reg_map mbox;
struct cxl_reg_map memdev;
};
/**
* struct cxl_register_map - DVSEC harvested register block mapping parameters
* @base: virtual base of the register-block-BAR + @block_offset
* @block_offset: offset to start of register block in @barno
* @reg_type: see enum cxl_regloc_type
* @barno: PCI BAR number containing the register block
* @component_map: cxl_reg_map for component registers
* @device_map: cxl_reg_maps for device registers
*/
struct cxl_register_map {
void __iomem *base;
u64 block_offset;
u8 reg_type;
u8 barno;
union {
struct cxl_component_reg_map component_map;
struct cxl_device_reg_map device_map;
};
};
void cxl_probe_component_regs(struct device *dev, void __iomem *base,
struct cxl_component_reg_map *map);
void cxl_probe_device_regs(struct device *dev, void __iomem *base,
struct cxl_device_reg_map *map);
int cxl_map_component_regs(struct pci_dev *pdev,
struct cxl_component_regs *regs,
struct cxl_register_map *map);
int cxl_map_device_regs(struct pci_dev *pdev,
struct cxl_device_regs *regs,
struct cxl_register_map *map);
#define CXL_RESOURCE_NONE ((resource_size_t) -1)
#define CXL_TARGET_STRLEN 20
/*
* cxl_decoder flags that define the type of memory / devices this
* decoder supports as well as configuration lock status See "CXL 2.0
* 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
*/
#define CXL_DECODER_F_RAM BIT(0)
#define CXL_DECODER_F_PMEM BIT(1)
#define CXL_DECODER_F_TYPE2 BIT(2)
#define CXL_DECODER_F_TYPE3 BIT(3)
#define CXL_DECODER_F_LOCK BIT(4)
#define CXL_DECODER_F_MASK GENMASK(4, 0)
enum cxl_decoder_type {
CXL_DECODER_ACCELERATOR = 2,
CXL_DECODER_EXPANDER = 3,
};
/*
* Current specification goes up to 8, double that seems a reasonable
* software max for the foreseeable future
*/
#define CXL_DECODER_MAX_INTERLEAVE 16
/**
* struct cxl_decoder - CXL address range decode configuration
* @dev: this decoder's device
* @id: kernel device name id
* @range: address range considered by this decoder
* @interleave_ways: number of cxl_dports in this decode
* @interleave_granularity: data stride per dport
* @target_type: accelerator vs expander (type2 vs type3) selector
* @flags: memory type capabilities and locking
* @nr_targets: number of elements in @target
* @target: active ordered target list in current decoder configuration
*/
struct cxl_decoder {
struct device dev;
int id;
struct range range;
int interleave_ways;
int interleave_granularity;
enum cxl_decoder_type target_type;
unsigned long flags;
int nr_targets;
struct cxl_dport *target[];
};
/**
* enum cxl_nvdimm_brige_state - state machine for managing bus rescans
* @CXL_NVB_NEW: Set at bridge create and after cxl_pmem_wq is destroyed
* @CXL_NVB_DEAD: Set at brige unregistration to preclude async probing
* @CXL_NVB_ONLINE: Target state after successful ->probe()
* @CXL_NVB_OFFLINE: Target state after ->remove() or failed ->probe()
*/
enum cxl_nvdimm_brige_state {
CXL_NVB_NEW,
CXL_NVB_DEAD,
CXL_NVB_ONLINE,
CXL_NVB_OFFLINE,
};
struct cxl_nvdimm_bridge {
int id;
struct device dev;
struct cxl_port *port;
struct nvdimm_bus *nvdimm_bus;
struct nvdimm_bus_descriptor nd_desc;
struct work_struct state_work;
enum cxl_nvdimm_brige_state state;
};
struct cxl_nvdimm {
struct device dev;
struct cxl_memdev *cxlmd;
struct nvdimm *nvdimm;
};
struct cxl_walk_context {
struct device *dev;
struct pci_bus *root;
struct cxl_port *port;
int error;
int count;
};
/**
* struct cxl_port - logical collection of upstream port devices and
* downstream port devices to construct a CXL memory
* decode hierarchy.
* @dev: this port's device
* @uport: PCI or platform device implementing the upstream port capability
* @id: id for port device-name
* @dports: cxl_dport instances referenced by decoders
* @decoder_ida: allocator for decoder ids
* @component_reg_phys: component register capability base address (optional)
*/
struct cxl_port {
struct device dev;
struct device *uport;
int id;
struct list_head dports;
struct ida decoder_ida;
resource_size_t component_reg_phys;
};
/**
* struct cxl_dport - CXL downstream port
* @dport: PCI bridge or firmware device representing the downstream link
* @port_id: unique hardware identifier for dport in decoder target list
* @component_reg_phys: downstream port component registers
* @port: reference to cxl_port that contains this downstream port
* @list: node for a cxl_port's list of cxl_dport instances
*/
struct cxl_dport {
struct device *dport;
int port_id;
resource_size_t component_reg_phys;
struct cxl_port *port;
struct list_head list;
};
struct cxl_port *to_cxl_port(struct device *dev);
struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport,
resource_size_t component_reg_phys,
struct cxl_port *parent_port);
int cxl_add_dport(struct cxl_port *port, struct device *dport, int port_id,
resource_size_t component_reg_phys);
struct cxl_decoder *to_cxl_decoder(struct device *dev);
bool is_root_decoder(struct device *dev);
struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets);
int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
extern struct bus_type cxl_bus_type;
struct cxl_driver {
const char *name;
int (*probe)(struct device *dev);
void (*remove)(struct device *dev);
struct device_driver drv;
int id;
};
static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
{
return container_of(drv, struct cxl_driver, drv);
}
int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
const char *modname);
#define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
void cxl_driver_unregister(struct cxl_driver *cxl_drv);
#define CXL_DEVICE_NVDIMM_BRIDGE 1
#define CXL_DEVICE_NVDIMM 2
#define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
#define CXL_MODALIAS_FMT "cxl:t%d"
struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
struct cxl_port *port);
struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
bool is_cxl_nvdimm(struct device *dev);
bool is_cxl_nvdimm_bridge(struct device *dev);
int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd);
struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd);
/*
* Unit test builds overrides this to __weak, find the 'strong' version
* of these symbols in tools/testing/cxl/.
*/
#ifndef __mock
#define __mock static
#endif
#endif /* __CXL_H__ */