mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 03:10:12 +00:00
![Ben Widawsky](/assets/img/avatar_default.png)
CXL devices identified by the memory-device class code must implement the Device Command Interface (described in 8.2.9 of the CXL 2.0 spec). While the driver already maintains a list of commands it supports, there is still a need to be able to distinguish between commands that the driver knows about from commands that are optionally supported by the hardware. The Command Effects Log (CEL) is specified in the CXL 2.0 specification. The CEL is one of two types of logs, the other being vendor specific. They are distinguished in hardware/spec via UUID. The CEL is useful for 2 things: 1. Determine which optional commands are supported by the CXL device. 2. Enumerate any vendor specific commands The CEL is used by the driver to determine which commands are available in the hardware and therefore which commands userspace is allowed to execute. The set of enabled commands might be a subset of commands which are advertised in UAPI via CXL_MEM_SEND_COMMAND IOCTL. With the CEL enabling comes a internal flag to indicate a base set of commands that are enabled regardless of CEL. Such commands are required for basic interaction with the hardware and thus can be useful in debug cases, for example if the CEL is corrupted. The implementation leaves the statically defined table of commands and supplements it with a bitmap to determine commands that are enabled. This organization was chosen for the following reasons: - Smaller memory footprint. Doesn't need a table per device. - Reduce memory allocation complexity. - Fixed command IDs to opcode mapping for all devices makes development and debugging easier. - Certain helpers are easily achievable, like cxl_for_each_cmd(). Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> (v3) Link: https://lore.kernel.org/r/20210217040958.1354670-7-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
95 lines
3.4 KiB
C
95 lines
3.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/* Copyright(c) 2020 Intel Corporation. */
|
|
|
|
#ifndef __CXL_H__
|
|
#define __CXL_H__
|
|
|
|
#include <linux/bitfield.h>
|
|
#include <linux/bitops.h>
|
|
#include <linux/io.h>
|
|
|
|
/* 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
|
|
|
|
/* CXL 2.0 8.2.8.5.1.1 Memory Device Status Register */
|
|
#define CXLMDEV_STATUS_OFFSET 0x0
|
|
#define CXLMDEV_DEV_FATAL BIT(0)
|
|
#define CXLMDEV_FW_HALT BIT(1)
|
|
#define CXLMDEV_STATUS_MEDIA_STATUS_MASK GENMASK(3, 2)
|
|
#define CXLMDEV_MS_NOT_READY 0
|
|
#define CXLMDEV_MS_READY 1
|
|
#define CXLMDEV_MS_ERROR 2
|
|
#define CXLMDEV_MS_DISABLED 3
|
|
#define CXLMDEV_READY(status) \
|
|
(FIELD_GET(CXLMDEV_STATUS_MEDIA_STATUS_MASK, status) == \
|
|
CXLMDEV_MS_READY)
|
|
#define CXLMDEV_MBOX_IF_READY BIT(4)
|
|
#define CXLMDEV_RESET_NEEDED_MASK GENMASK(7, 5)
|
|
#define CXLMDEV_RESET_NEEDED_NOT 0
|
|
#define CXLMDEV_RESET_NEEDED_COLD 1
|
|
#define CXLMDEV_RESET_NEEDED_WARM 2
|
|
#define CXLMDEV_RESET_NEEDED_HOT 3
|
|
#define CXLMDEV_RESET_NEEDED_CXL 4
|
|
#define CXLMDEV_RESET_NEEDED(status) \
|
|
(FIELD_GET(CXLMDEV_RESET_NEEDED_MASK, status) != \
|
|
CXLMDEV_RESET_NEEDED_NOT)
|
|
|
|
struct cxl_memdev;
|
|
/**
|
|
* struct cxl_mem - A CXL memory device
|
|
* @pdev: The PCI device associated with this CXL device.
|
|
* @regs: IO mappings to the device's MMIO
|
|
* @status_regs: CXL 2.0 8.2.8.3 Device Status Registers
|
|
* @mbox_regs: CXL 2.0 8.2.8.4 Mailbox Registers
|
|
* @memdev_regs: CXL 2.0 8.2.8.5 Memory Device Registers
|
|
* @payload_size: Size of space for payload
|
|
* (CXL 2.0 8.2.8.4.3 Mailbox Capabilities Register)
|
|
* @mbox_mutex: Mutex to synchronize mailbox access.
|
|
* @firmware_version: Firmware version for the memory device.
|
|
* @enabled_commands: Hardware commands found enabled in CEL.
|
|
* @pmem_range: Persistent memory capacity information.
|
|
* @ram_range: Volatile memory capacity information.
|
|
*/
|
|
struct cxl_mem {
|
|
struct pci_dev *pdev;
|
|
void __iomem *regs;
|
|
struct cxl_memdev *cxlmd;
|
|
|
|
void __iomem *status_regs;
|
|
void __iomem *mbox_regs;
|
|
void __iomem *memdev_regs;
|
|
|
|
size_t payload_size;
|
|
struct mutex mbox_mutex; /* Protects device mailbox and firmware */
|
|
char firmware_version[0x10];
|
|
unsigned long *enabled_cmds;
|
|
|
|
struct range pmem_range;
|
|
struct range ram_range;
|
|
};
|
|
|
|
extern struct bus_type cxl_bus_type;
|
|
#endif /* __CXL_H__ */
|