[PATCH v4 1/8] cxl/mem: Move some definitions to mem.h

From: Dan Williams
Date: Fri May 14 2021 - 01:21:54 EST


In preparation for sharing cxl.h with other generic CXL consumers,
move / consolidate some of the memory device specifics to mem.h.

The motivation for moving out of cxl.h is to maintain least privilege
access to memory-device details since cxl.h is used in multiple files.
The motivation for moving definitions into a new mem.h header is for
code readability and organization. I.e. minimize implementation details
when reading data structures and other definitions.

Reviewed-by: Ben Widawsky <ben.widawsky@xxxxxxxxx>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/cxl/cxl.h | 57 -------------------------------------
drivers/cxl/mem.c | 21 +-------------
drivers/cxl/mem.h | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 82 insertions(+), 77 deletions(-)
create mode 100644 drivers/cxl/mem.h

diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 6f14838c2d25..2e3bdacb32e7 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -34,62 +34,5 @@
#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__ */
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 2acc6173da36..53933d7d8d12 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -13,6 +13,7 @@
#include <linux/io-64-nonatomic-lo-hi.h>
#include "pci.h"
#include "cxl.h"
+#include "mem.h"

/**
* DOC: cxl mem
@@ -30,12 +31,6 @@
* - Handle and manage error conditions.
*/

-/*
- * An entire PCI topology full of devices should be enough for any
- * config
- */
-#define CXL_MEM_MAX_DEVS 65536
-
#define cxl_doorbell_busy(cxlm) \
(readl((cxlm)->mbox_regs + CXLDEV_MBOX_CTRL_OFFSET) & \
CXLDEV_MBOX_CTRL_DOORBELL)
@@ -92,20 +87,6 @@ struct mbox_cmd {
#define CXL_MBOX_SUCCESS 0
};

-/**
- * struct cxl_memdev - CXL bus object representing a Type-3 Memory Device
- * @dev: driver core device object
- * @cdev: char dev core object for ioctl operations
- * @cxlm: pointer to the parent device driver data
- * @id: id number of this memdev instance.
- */
-struct cxl_memdev {
- struct device dev;
- struct cdev cdev;
- struct cxl_mem *cxlm;
- int id;
-};
-
static int cxl_mem_major;
static DEFINE_IDA(cxl_memdev_ida);
static DECLARE_RWSEM(cxl_memdev_rwsem);
diff --git a/drivers/cxl/mem.h b/drivers/cxl/mem.h
new file mode 100644
index 000000000000..451db0984b92
--- /dev/null
+++ b/drivers/cxl/mem.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright(c) 2020-2021 Intel Corporation. */
+#ifndef __CXL_MEM_H__
+#define __CXL_MEM_H__
+
+/* 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)
+
+/*
+ * An entire PCI topology full of devices should be enough for any
+ * config
+ */
+#define CXL_MEM_MAX_DEVS 65536
+
+/**
+ * struct cxl_memdev - CXL bus object representing a Type-3 Memory Device
+ * @dev: driver core device object
+ * @cdev: char dev core object for ioctl operations
+ * @cxlm: pointer to the parent device driver data
+ * @id: id number of this memdev instance.
+ */
+struct cxl_memdev {
+ struct device dev;
+ struct cdev cdev;
+ struct cxl_mem *cxlm;
+ int id;
+};
+
+/**
+ * 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_cmds: 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;
+};
+#endif /* __CXL_MEM_H__ */