[PATCH v10 04/10] PCI: endpoint: Add pci-epf-ntb.h for the shared NTB control layout

[Koichiro Den <den@valinux.co.jp>]

Currently, pci-epf-ntb.c and pci-epf-vntb.c each define struct
epf_ntb_ctrl, and ntb_hw_epf.c mirrors the same layout with hard-coded
register offsets.

Move the shared struct and macros to include/linux/pci-epf-ntb.h. The
vNTB "reserved" field takes the pci-epf-ntb.c name mw1_offset, which is
what ntb_hw_epf.c reads at that offset.

No functional changes.

Suggested-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Koichiro Den <den@valinux.co.jp>
---
Changes since v7:
  - No changes.

 MAINTAINERS                                   |   1 +
 drivers/pci/endpoint/functions/pci-epf-ntb.c  |  85 ++++--------
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 131 +++++++-----------
 include/linux/pci-epf-ntb.h                   |  48 +++++++
 4 files changed, 128 insertions(+), 137 deletions(-)
 create mode 100644 include/linux/pci-epf-ntb.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 93abbb315065..ebdbc54c72d9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19934,6 +19934,7 @@ F:	drivers/ntb/
 F:	drivers/pci/endpoint/functions/pci-epf-*ntb.c
 F:	include/linux/ntb.h
 F:	include/linux/ntb_transport.h
+F:	include/linux/pci-epf-ntb.h
 F:	tools/testing/selftests/ntb/
 
 NTB INTEL DRIVER
diff --git a/drivers/pci/endpoint/functions/pci-epf-ntb.c b/drivers/pci/endpoint/functions/pci-epf-ntb.c
index 5314aca2188a..925cf46219d7 100644
--- a/drivers/pci/endpoint/functions/pci-epf-ntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-ntb.c
@@ -41,27 +41,13 @@
 
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
+#include <linux/pci-epf-ntb.h>
 
 static struct workqueue_struct *kpcintb_workqueue;
 
-#define COMMAND_CONFIGURE_DOORBELL	1
-#define COMMAND_TEARDOWN_DOORBELL	2
-#define COMMAND_CONFIGURE_MW		3
-#define COMMAND_TEARDOWN_MW		4
-#define COMMAND_LINK_UP			5
-#define COMMAND_LINK_DOWN		6
-
-#define COMMAND_STATUS_OK		1
-#define COMMAND_STATUS_ERROR		2
-
-#define LINK_STATUS_UP			BIT(0)
-
 #define SPAD_COUNT			64
 #define DB_COUNT			4
 #define NTB_MW_OFFSET			2
-#define DB_COUNT_MASK			GENMASK(15, 0)
-#define MSIX_ENABLE			BIT(16)
-#define MAX_DB_COUNT			32
 #define MAX_MW				4
 
 enum epf_ntb_bar {
@@ -104,23 +90,6 @@ struct epf_ntb_epc {
 	const struct pci_epc_features *epc_features;
 };
 
-struct epf_ntb_ctrl {
-	u32	command;
-	u32	argument;
-	u16	command_status;
-	u16	link_status;
-	u32	topology;
-	u64	addr;
-	u64	size;
-	u32	num_mws;
-	u32	mw1_offset;
-	u32	spad_offset;
-	u32	spad_count;
-	u32	db_entry_size;
-	u32	db_data[MAX_DB_COUNT];
-	u32	db_offset[MAX_DB_COUNT];
-} __packed;
-
 static struct pci_epf_header epf_ntb_header = {
 	.vendorid	= PCI_ANY_ID,
 	.deviceid	= PCI_ANY_ID,
@@ -156,9 +125,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
 		is_msix = ntb_epc->is_msix;
 		ctrl = ntb_epc->reg;
 		if (link_up)
-			ctrl->link_status |= LINK_STATUS_UP;
+			ctrl->link_status |= EPF_NTB_LINK_STATUS_UP;
 		else
-			ctrl->link_status &= ~LINK_STATUS_UP;
+			ctrl->link_status &= ~EPF_NTB_LINK_STATUS_UP;
 		irq_type = is_msix ? PCI_IRQ_MSIX : PCI_IRQ_MSI;
 		ret = pci_epc_raise_irq(epc, func_no, vfunc_no, irq_type, 1);
 		if (ret) {
@@ -562,9 +531,9 @@ static int epf_ntb_configure_db(struct epf_ntb *ntb,
 	ntb_epc = ntb->epc[type];
 	epc = ntb_epc->epc;
 
-	if (!db_count || db_count > MAX_DB_COUNT) {
+	if (!db_count || db_count > EPF_NTB_MAX_DB_COUNT) {
 		dev_err(&epc->dev, "DB count %d out of range (1 - %d)\n",
-			db_count, MAX_DB_COUNT);
+			db_count, EPF_NTB_MAX_DB_COUNT);
 		return -EINVAL;
 	}
 
@@ -648,50 +617,52 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 	dev = &ntb->epf->dev;
 
 	switch (command) {
-	case COMMAND_CONFIGURE_DOORBELL:
-		db_count = argument & DB_COUNT_MASK;
-		is_msix = argument & MSIX_ENABLE;
+	case EPF_NTB_COMMAND_CONFIGURE_DOORBELL:
+		db_count = argument & EPF_NTB_DB_COUNT_MASK;
+		is_msix = argument & EPF_NTB_MSIX_ENABLE;
 		ret = epf_ntb_configure_db(ntb, type, db_count, is_msix);
 		if (ret < 0)
-			ctrl->command_status = COMMAND_STATUS_ERROR;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_ERROR;
 		else
-			ctrl->command_status = COMMAND_STATUS_OK;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_TEARDOWN_DOORBELL:
+	case EPF_NTB_COMMAND_TEARDOWN_DOORBELL:
 		epf_ntb_teardown_db(ntb, type);
-		ctrl->command_status = COMMAND_STATUS_OK;
+		ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_CONFIGURE_MW:
+	case EPF_NTB_COMMAND_CONFIGURE_MW:
 		ret = epf_ntb_configure_mw(ntb, type, argument);
 		if (ret < 0)
-			ctrl->command_status = COMMAND_STATUS_ERROR;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_ERROR;
 		else
-			ctrl->command_status = COMMAND_STATUS_OK;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_TEARDOWN_MW:
+	case EPF_NTB_COMMAND_TEARDOWN_MW:
 		epf_ntb_teardown_mw(ntb, type, argument);
-		ctrl->command_status = COMMAND_STATUS_OK;
+		ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_LINK_UP:
+	case EPF_NTB_COMMAND_LINK_UP:
 		ntb_epc->linkup = true;
 		if (ntb->epc[PRIMARY_INTERFACE]->linkup &&
 		    ntb->epc[SECONDARY_INTERFACE]->linkup) {
 			ret = epf_ntb_link_up(ntb, true);
 			if (ret < 0)
-				ctrl->command_status = COMMAND_STATUS_ERROR;
+				ctrl->command_status =
+					EPF_NTB_COMMAND_STATUS_ERROR;
 			else
-				ctrl->command_status = COMMAND_STATUS_OK;
+				ctrl->command_status =
+					EPF_NTB_COMMAND_STATUS_OK;
 			goto reset_handler;
 		}
-		ctrl->command_status = COMMAND_STATUS_OK;
+		ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_LINK_DOWN:
+	case EPF_NTB_COMMAND_LINK_DOWN:
 		ntb_epc->linkup = false;
 		ret = epf_ntb_link_up(ntb, false);
 		if (ret < 0)
-			ctrl->command_status = COMMAND_STATUS_ERROR;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_ERROR;
 		else
-			ctrl->command_status = COMMAND_STATUS_OK;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
 	default:
 		dev_err(dev, "%s intf UNKNOWN command: %d\n",
@@ -1298,9 +1269,9 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb,
 	func_no = ntb_epc->func_no;
 	vfunc_no = ntb_epc->vfunc_no;
 
-	if (!ntb->db_count || ntb->db_count > MAX_DB_COUNT) {
+	if (!ntb->db_count || ntb->db_count > EPF_NTB_MAX_DB_COUNT) {
 		dev_err(dev, "DB count %d out of range (1 - %d)\n",
-			ntb->db_count, MAX_DB_COUNT);
+			ntb->db_count, EPF_NTB_MAX_DB_COUNT);
 		return -EINVAL;
 	}
 
diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 1a0ce31e680c..3adbaa9d85db 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -47,27 +47,14 @@
 #include <linux/pci-ep-msi.h>
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
+#include <linux/pci-epf-ntb.h>
 #include <linux/ntb.h>
 
 static struct workqueue_struct *kpcintb_workqueue;
 
-#define COMMAND_CONFIGURE_DOORBELL	1
-#define COMMAND_TEARDOWN_DOORBELL	2
-#define COMMAND_CONFIGURE_MW		3
-#define COMMAND_TEARDOWN_MW		4
-#define COMMAND_LINK_UP			5
-#define COMMAND_LINK_DOWN		6
-
-#define COMMAND_STATUS_OK		1
-#define COMMAND_STATUS_ERROR		2
-
-#define LINK_STATUS_UP			BIT(0)
-
 #define SPAD_COUNT			64
 #define DB_COUNT			4
 #define NTB_MW_OFFSET			2
-#define DB_COUNT_MASK			GENMASK(15, 0)
-#define MSIX_ENABLE			BIT(16)
 #define MAX_MW				4
 
 /* Limit per-work execution to avoid monopolizing kworker on doorbell storms. */
@@ -90,47 +77,6 @@ enum epf_irq_slot {
 };
 
 #define MIN_DB_COUNT			(EPF_IRQ_DB_START + 1)
-#define MAX_DB_COUNT			32
-
-/*
- * +--------------------------------------------------+ Base
- * |                                                  |
- * |                                                  |
- * |                                                  |
- * |          Common Control Register                 |
- * |                                                  |
- * |                                                  |
- * |                                                  |
- * +-----------------------+--------------------------+ Base+spad_offset
- * |                       |                          |
- * |    Peer Spad Space    |    Spad Space            |
- * |                       |                          |
- * |                       |                          |
- * +-----------------------+--------------------------+ Base+spad_offset
- * |                       |                          |     +spad_count * 4
- * |                       |                          |
- * |     Spad Space        |   Peer Spad Space        |
- * |                       |                          |
- * +-----------------------+--------------------------+
- *       Virtual PCI             PCIe Endpoint
- *       NTB Driver               NTB Driver
- */
-struct epf_ntb_ctrl {
-	u32 command;
-	u32 argument;
-	u16 command_status;
-	u16 link_status;
-	u32 topology;
-	u64 addr;
-	u64 size;
-	u32 num_mws;
-	u32 reserved;
-	u32 spad_offset;
-	u32 spad_count;
-	u32 db_entry_size;
-	u32 db_data[MAX_DB_COUNT];
-	u32 db_offset[MAX_DB_COUNT];
-} __packed;
 
 struct epf_ntb {
 	struct ntb_dev *ntb;
@@ -195,9 +141,9 @@ static void epf_ntb_update_link(struct epf_ntb *ntb)
 
 	/* The link is usable only after both sides have enabled it. */
 	if (ntb->host_link_enabled && ntb->vhost_link_enabled)
-		link_status |= LINK_STATUS_UP;
+		link_status |= EPF_NTB_LINK_STATUS_UP;
 	else
-		link_status &= ~LINK_STATUS_UP;
+		link_status &= ~EPF_NTB_LINK_STATUS_UP;
 
 	WRITE_ONCE(ntb->reg->link_status, link_status);
 }
@@ -368,45 +314,47 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 	dev = &ntb->epf->dev;
 
 	switch (command) {
-	case COMMAND_CONFIGURE_DOORBELL:
+	case EPF_NTB_COMMAND_CONFIGURE_DOORBELL:
 		epc_features = pci_epc_get_features(ntb->epf->epc,
 						    ntb->epf->func_no,
 						    ntb->epf->vfunc_no);
-		if (((argument & MSIX_ENABLE) && !epc_features->msix_capable) ||
-		    (!(argument & MSIX_ENABLE) && !epc_features->msi_capable)) {
-			ctrl->command_status = COMMAND_STATUS_ERROR;
+		if (((argument & EPF_NTB_MSIX_ENABLE) &&
+		     !epc_features->msix_capable) ||
+		    (!(argument & EPF_NTB_MSIX_ENABLE) &&
+		     !epc_features->msi_capable)) {
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_ERROR;
 			break;
 		}
-		ntb->peer_msix = argument & MSIX_ENABLE;
-		ctrl->command_status = COMMAND_STATUS_OK;
+		ntb->peer_msix = argument & EPF_NTB_MSIX_ENABLE;
+		ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_TEARDOWN_DOORBELL:
-		ctrl->command_status = COMMAND_STATUS_OK;
+	case EPF_NTB_COMMAND_TEARDOWN_DOORBELL:
+		ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_CONFIGURE_MW:
+	case EPF_NTB_COMMAND_CONFIGURE_MW:
 		ret = epf_ntb_configure_mw(ntb, argument);
 		if (ret < 0)
-			ctrl->command_status = COMMAND_STATUS_ERROR;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_ERROR;
 		else
-			ctrl->command_status = COMMAND_STATUS_OK;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_TEARDOWN_MW:
+	case EPF_NTB_COMMAND_TEARDOWN_MW:
 		epf_ntb_teardown_mw(ntb, argument);
-		ctrl->command_status = COMMAND_STATUS_OK;
+		ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
-	case COMMAND_LINK_UP:
+	case EPF_NTB_COMMAND_LINK_UP:
 		ret = epf_ntb_set_link_enabled(ntb, true);
 		if (ret < 0)
-			ctrl->command_status = COMMAND_STATUS_ERROR;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_ERROR;
 		else
-			ctrl->command_status = COMMAND_STATUS_OK;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		goto reset_handler;
-	case COMMAND_LINK_DOWN:
+	case EPF_NTB_COMMAND_LINK_DOWN:
 		ret = epf_ntb_set_link_enabled(ntb, false);
 		if (ret < 0)
-			ctrl->command_status = COMMAND_STATUS_ERROR;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_ERROR;
 		else
-			ctrl->command_status = COMMAND_STATUS_OK;
+			ctrl->command_status = EPF_NTB_COMMAND_STATUS_OK;
 		break;
 	default:
 		dev_err(dev, "UNKNOWN command: %d\n", command);
@@ -518,6 +466,28 @@ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
  *   region
  * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
+ * +--------------------------------------------------+ Base
+ * |                                                  |
+ * |                                                  |
+ * |                                                  |
+ * |          Common Control Register                 |
+ * |                                                  |
+ * |                                                  |
+ * |                                                  |
+ * +-----------------------+--------------------------+ Base+spad_offset
+ * |                       |                          |
+ * |    Peer Spad Space    |    Spad Space            |
+ * |                       |                          |
+ * |                       |                          |
+ * +-----------------------+--------------------------+ Base+spad_offset
+ * |                       |                          |     +spad_count * 4
+ * |                       |                          |
+ * |     Spad Space        |   Peer Spad Space        |
+ * |                       |                          |
+ * +-----------------------+--------------------------+
+ *       Virtual PCI             PCIe Endpoint
+ *       NTB Driver               NTB Driver
+ *
  * Allocate the Local Memory mentioned in the above diagram. The size of
  * CONFIG REGION is sizeof(struct epf_ntb_ctrl), plus space for the MSI-X
  * Table and PBA if supported. The size of SCRATCHPAD REGION is obtained
@@ -602,9 +572,10 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 		return -EINVAL;
 	}
 
-	if (ntb->db_count < MIN_DB_COUNT || ntb->db_count > MAX_DB_COUNT) {
+	if (ntb->db_count < MIN_DB_COUNT ||
+	    ntb->db_count > EPF_NTB_MAX_DB_COUNT) {
 		dev_err(dev, "DB count %d out of range (%d - %d)\n",
-			ntb->db_count, MIN_DB_COUNT, MAX_DB_COUNT);
+			ntb->db_count, MIN_DB_COUNT, EPF_NTB_MAX_DB_COUNT);
 		return -EINVAL;
 	}
 
@@ -1258,7 +1229,7 @@ static ssize_t epf_ntb_db_count_store(struct config_item *item,
 	if (ret)
 		return ret;
 
-	if (val < MIN_DB_COUNT || val > MAX_DB_COUNT)
+	if (val < MIN_DB_COUNT || val > EPF_NTB_MAX_DB_COUNT)
 		return -EINVAL;
 
 	WRITE_ONCE(ntb->db_count, val);
@@ -1456,7 +1427,7 @@ static int vntb_epf_db_vector_count(struct ntb_dev *ntb)
 	 *
 	 * Report only usable per-vector doorbell interrupts.
 	 */
-	if (db_count < MIN_DB_COUNT || db_count > MAX_DB_COUNT)
+	if (db_count < MIN_DB_COUNT || db_count > EPF_NTB_MAX_DB_COUNT)
 		return 0;
 
 	return db_count - EPF_IRQ_DB_START;
diff --git a/include/linux/pci-epf-ntb.h b/include/linux/pci-epf-ntb.h
new file mode 100644
index 000000000000..0c02d709aa08
--- /dev/null
+++ b/include/linux/pci-epf-ntb.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Control region layout shared by the PCI endpoint NTB function drivers
+ * (pci-epf-ntb, pci-epf-vntb) and the host side ntb_hw_epf driver.
+ */
+
+#ifndef __LINUX_PCI_EPF_NTB_H
+#define __LINUX_PCI_EPF_NTB_H
+
+#include <linux/bits.h>
+#include <linux/types.h>
+
+#define EPF_NTB_COMMAND_CONFIGURE_DOORBELL	1
+#define EPF_NTB_COMMAND_TEARDOWN_DOORBELL	2
+#define EPF_NTB_COMMAND_CONFIGURE_MW		3
+#define EPF_NTB_COMMAND_TEARDOWN_MW		4
+#define EPF_NTB_COMMAND_LINK_UP			5
+#define EPF_NTB_COMMAND_LINK_DOWN		6
+
+/* EPF_NTB_COMMAND_CONFIGURE_DOORBELL argument */
+#define EPF_NTB_DB_COUNT_MASK			GENMASK(15, 0)
+#define EPF_NTB_MSIX_ENABLE			BIT(16)
+
+#define EPF_NTB_COMMAND_STATUS_OK		1
+#define EPF_NTB_COMMAND_STATUS_ERROR		2
+
+#define EPF_NTB_LINK_STATUS_UP			BIT(0)
+
+#define EPF_NTB_MAX_DB_COUNT			32
+
+struct epf_ntb_ctrl {
+	u32 command;
+	u32 argument;
+	u16 command_status;
+	u16 link_status;
+	u32 topology;
+	u64 addr;
+	u64 size;
+	u32 num_mws;
+	u32 mw1_offset;
+	u32 spad_offset;
+	u32 spad_count;
+	u32 db_entry_size;
+	u32 db_data[EPF_NTB_MAX_DB_COUNT];
+	u32 db_offset[EPF_NTB_MAX_DB_COUNT];
+} __packed;
+
+#endif /* __LINUX_PCI_EPF_NTB_H */
-- 
2.54.0