cxlflash: Base support for IBM CXL Flash Adapter
SCSI device driver to support filesystem access on the IBM CXL Flash adapter.
Supported-by: Stephen Bates <stephen.bates@pmcs.com>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
new file mode 100644
index 0000000..5f43608
--- /dev/null
+++ b/drivers/scsi/cxlflash/common.h
@@ -0,0 +1,180 @@
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
+ * Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2015 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _CXLFLASH_COMMON_H
+#define _CXLFLASH_COMMON_H
+
+#include <linux/list.h>
+#include <linux/types.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_device.h>
+
+
+#define MAX_CONTEXT CXLFLASH_MAX_CONTEXT /* num contexts per afu */
+
+#define CXLFLASH_BLOCK_SIZE 4096 /* 4K blocks */
+#define CXLFLASH_MAX_XFER_SIZE 16777216 /* 16MB transfer */
+#define CXLFLASH_MAX_SECTORS (CXLFLASH_MAX_XFER_SIZE/512) /* SCSI wants
+ max_sectors
+ in units of
+ 512 byte
+ sectors
+ */
+
+#define NUM_RRQ_ENTRY 16 /* for master issued cmds */
+#define MAX_RHT_PER_CONTEXT (PAGE_SIZE / sizeof(struct sisl_rht_entry))
+
+/* AFU command retry limit */
+#define MC_RETRY_CNT 5 /* sufficient for SCSI check and
+ certain AFU errors */
+
+/* Command management definitions */
+#define CXLFLASH_NUM_CMDS (2 * CXLFLASH_MAX_CMDS) /* Must be a pow2 for
+ alignment and more
+ efficient array
+ index derivation
+ */
+
+#define CXLFLASH_MAX_CMDS 16
+#define CXLFLASH_MAX_CMDS_PER_LUN CXLFLASH_MAX_CMDS
+
+
+static inline void check_sizes(void)
+{
+ BUILD_BUG_ON_NOT_POWER_OF_2(CXLFLASH_NUM_CMDS);
+}
+
+/* AFU defines a fixed size of 4K for command buffers (borrow 4K page define) */
+#define CMD_BUFSIZE SIZE_4K
+
+/* flags in IOA status area for host use */
+#define B_DONE 0x01
+#define B_ERROR 0x02 /* set with B_DONE */
+#define B_TIMEOUT 0x04 /* set with B_DONE & B_ERROR */
+
+enum cxlflash_lr_state {
+ LINK_RESET_INVALID,
+ LINK_RESET_REQUIRED,
+ LINK_RESET_COMPLETE
+};
+
+enum cxlflash_init_state {
+ INIT_STATE_NONE,
+ INIT_STATE_PCI,
+ INIT_STATE_AFU,
+ INIT_STATE_SCSI
+};
+
+/*
+ * Each context has its own set of resource handles that is visible
+ * only from that context.
+ */
+
+struct cxlflash_cfg {
+ struct afu *afu;
+ struct cxl_context *mcctx;
+
+ struct pci_dev *dev;
+ struct pci_device_id *dev_id;
+ struct Scsi_Host *host;
+
+ ulong cxlflash_regs_pci;
+
+ wait_queue_head_t eeh_waitq;
+
+ struct work_struct work_q;
+ enum cxlflash_init_state init_state;
+ enum cxlflash_lr_state lr_state;
+ int lr_port;
+
+ struct cxl_afu *cxl_afu;
+
+ struct pci_pool *cxlflash_cmd_pool;
+ struct pci_dev *parent_dev;
+
+ wait_queue_head_t tmf_waitq;
+ bool tmf_active;
+ u8 err_recovery_active:1;
+};
+
+struct afu_cmd {
+ struct sisl_ioarcb rcb; /* IOARCB (cache line aligned) */
+ struct sisl_ioasa sa; /* IOASA must follow IOARCB */
+ spinlock_t slock;
+ struct completion cevent;
+ char *buf; /* per command buffer */
+ struct afu *parent;
+ int slot;
+ atomic_t free;
+
+ u8 cmd_tmf:1;
+
+ /* As per the SISLITE spec the IOARCB EA has to be 16-byte aligned.
+ * However for performance reasons the IOARCB/IOASA should be
+ * cache line aligned.
+ */
+} __aligned(cache_line_size());
+
+struct afu {
+ /* Stuff requiring alignment go first. */
+
+ u64 rrq_entry[NUM_RRQ_ENTRY]; /* 128B RRQ */
+ /*
+ * Command & data for AFU commands.
+ */
+ struct afu_cmd cmd[CXLFLASH_NUM_CMDS];
+
+ /* Beware of alignment till here. Preferably introduce new
+ * fields after this point
+ */
+
+ /* AFU HW */
+ struct cxl_ioctl_start_work work;
+ struct cxlflash_afu_map *afu_map; /* entire MMIO map */
+ struct sisl_host_map *host_map; /* MC host map */
+ struct sisl_ctrl_map *ctrl_map; /* MC control map */
+
+ ctx_hndl_t ctx_hndl; /* master's context handle */
+ u64 *hrrq_start;
+ u64 *hrrq_end;
+ u64 *hrrq_curr;
+ bool toggle;
+ bool read_room;
+ atomic64_t room;
+ u64 hb;
+ u32 cmd_couts; /* Number of command checkouts */
+ u32 internal_lun; /* User-desired LUN mode for this AFU */
+
+ char version[8];
+ u64 interface_version;
+
+ struct cxlflash_cfg *parent; /* Pointer back to parent cxlflash_cfg */
+
+};
+
+static inline u64 lun_to_lunid(u64 lun)
+{
+ u64 lun_id;
+
+ int_to_scsilun(lun, (struct scsi_lun *)&lun_id);
+ return swab64(lun_id);
+}
+
+int cxlflash_send_cmd(struct afu *, struct afu_cmd *);
+void cxlflash_wait_resp(struct afu *, struct afu_cmd *);
+int cxlflash_afu_reset(struct cxlflash_cfg *);
+struct afu_cmd *cxlflash_cmd_checkout(struct afu *);
+void cxlflash_cmd_checkin(struct afu_cmd *);
+int cxlflash_afu_sync(struct afu *, ctx_hndl_t, res_hndl_t, u8);
+#endif /* ifndef _CXLFLASH_COMMON_H */