[PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

[PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

[Frank Li]

Remove unused field: epf_db_phy.
Remove __iomem before epf_db.
Change epf_db to u32* from void *
Remove duplicate check if (readl(ntb->epf_db + i * 4)).
Using sizeof(u32) instead of number 4 at all place.

Clean up sparse build warning:
  Using  epf_db[i] instead of readl() because epf_db is located in local
  memory and allocated by dma_alloc_coherent(). Sparse build warning when
  there are not __iomem at readl().
  Added __iomem force type convert in vntb_epf_peer_spad_read\write() and
  vntb_epf_spad_read\write(). This require strong order at read and write.

Replace pci_epc_mem_free_addr() with pci_epf_free_space() at error handle
path to match pci_epf_alloc_space().

Cleanup warning found by scripts/kernel-doc
Fix indentation of the struct epf_ntb_ctrl
Consolidate term
  host, host1 to HOST
  vhost, vHost, Vhost, VHOST2 to VHOST

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 157 ++++++++++--------
 1 file changed, 90 insertions(+), 67 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 1466dd1904175..acea753af29ed 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -11,7 +11,7 @@
  * Author: Kishon Vijay Abraham I <kishon@ti.com>
  */
 
-/**
+/*
  * +------------+         +---------------------------------------+
  * |            |         |                                       |
  * +------------+         |                        +--------------+
@@ -99,20 +99,20 @@ enum epf_ntb_bar {
  *       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];
+	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 {
@@ -136,8 +136,7 @@ struct epf_ntb {
 
 	struct epf_ntb_ctrl *reg;
 
-	phys_addr_t epf_db_phy;
-	void __iomem *epf_db;
+	u32 *epf_db;
 
 	phys_addr_t vpci_mw_phy[MAX_MW];
 	void __iomem *vpci_mw_addr[MAX_MW];
@@ -156,12 +155,14 @@ static struct pci_epf_header epf_ntb_header = {
 };
 
 /**
- * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
+ * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
  * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @link_up: true or false indicating Link is UP or Down
  *
  * Once NTB function in HOST invoke ntb_link_enable(),
- * this NTB function driver will trigger a link event to vhost.
+ * this NTB function driver will trigger a link event to VHOST.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
 {
@@ -175,9 +176,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
 }
 
 /**
- * epf_ntb_configure_mw() - Configure the Outbound Address Space for vhost
- *   to access the memory window of host
- * @ntb: NTB device that facilitates communication between host and vhost
+ * epf_ntb_configure_mw() - Configure the Outbound Address Space for VHOST
+ *   to access the memory window of HOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @mw: Index of the memory window (either 0, 1, 2 or 3)
  *
  *                          EP Outbound Window
@@ -194,7 +195,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
  * |        |              |           |
  * |        |              |           |
  * +--------+              +-----------+
- *  VHost                   PCI EP
+ *  VHOST                   PCI EP
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
 {
@@ -219,7 +222,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
 
 /**
  * epf_ntb_teardown_mw() - Teardown the configured OB ATU
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @mw: Index of the memory window (either 0, 1, 2 or 3)
  *
  * Teardown the configured OB ATU configured in epf_ntb_configure_mw() using
@@ -234,12 +237,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb *ntb, u32 mw)
 }
 
 /**
- * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
+ * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
  * @work: work_struct for the epf_ntb_epc
  *
  * Workqueue function that gets invoked for the two epf_ntb_epc
  * periodically (once every 5ms) to see if it has received any commands
- * from NTB host. The host can send commands to configure doorbell or
+ * from NTB HOST. The HOST can send commands to configure doorbell or
  * configure memory window or to update link status.
  */
 static void epf_ntb_cmd_handler(struct work_struct *work)
@@ -254,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
 
 	for (i = 1; i < ntb->db_count; i++) {
-		if (readl(ntb->epf_db + i * 4)) {
-			if (readl(ntb->epf_db + i * 4))
-				ntb->db |= 1 << (i - 1);
-
+		if (ntb->epf_db[i]) {
 			ntb_db_event(&ntb->ntb, i);
-			writel(0, ntb->epf_db + i * 4);
+			ntb->epf_db[i] = 0;
 		}
 	}
 
@@ -321,8 +321,8 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 
 /**
  * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
- * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound
- *	     address.
+ * @ntb: EPC associated with one of the HOST which holds peer's outbound
+ *	 address.
  *
  * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
  * self scratchpad region (removes inbound ATU configuration). While BAR0 is
@@ -331,8 +331,10 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
  * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
  *
  * Please note the self scratchpad region and config region is combined to
- * a single region and mapped using the same BAR. Also note HOST2's peer
- * scratchpad is HOST1's self scratchpad.
+ * a single region and mapped using the same BAR. Also note VHOST's peer
+ * scratchpad is HOST's self scratchpad.
+ *
+ * Returns: void
  */
 static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
 {
@@ -347,13 +349,15 @@ static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
- * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
+ * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
  * self scratchpad region.
  *
  * Please note the self scratchpad region and config region is combined to
  * a single region and mapped using the same BAR.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
 {
@@ -380,7 +384,7 @@ static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
 /**
  * epf_ntb_config_spad_bar_free() - Free the physical memory associated with
  *   config + scratchpad region
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
 {
@@ -393,11 +397,13 @@ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
 /**
  * epf_ntb_config_spad_bar_alloc() - Allocate memory for config + scratchpad
  *   region
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Allocate the Local Memory mentioned in the above diagram. The size of
  * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD REGION
  * is obtained from "spad-count" configfs entry.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 {
@@ -424,7 +430,7 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 	spad_count = ntb->spad_count;
 
 	ctrl_size = sizeof(struct epf_ntb_ctrl);
-	spad_size = 2 * spad_count * 4;
+	spad_size = 2 * spad_count * sizeof(u32);
 
 	if (!align) {
 		ctrl_size = roundup_pow_of_two(ctrl_size);
@@ -454,7 +460,7 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 	ctrl->num_mws = ntb->num_mws;
 	ntb->spad_size = spad_size;
 
-	ctrl->db_entry_size = 4;
+	ctrl->db_entry_size = sizeof(u32);
 
 	for (i = 0; i < ntb->db_count; i++) {
 		ntb->reg->db_data[i] = 1 + i;
@@ -465,11 +471,13 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 }
 
 /**
- * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Configure MSI/MSI-X capability for each interface with number of
  * interrupts equal to "db_count" configfs entry.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 {
@@ -511,18 +519,22 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_db_bar_init() - Configure Doorbell window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 {
 	const struct pci_epc_features *epc_features;
-	u32 align;
 	struct device *dev = &ntb->epf->dev;
-	int ret;
 	struct pci_epf_bar *epf_bar;
-	void __iomem *mw_addr;
 	enum pci_barno barno;
-	size_t size = 4 * ntb->db_count;
+	void *mw_addr;
+	size_t size;
+	u32 align;
+	int ret;
+
+	size = sizeof(u32) * ntb->db_count;
 
 	epc_features = pci_epc_get_features(ntb->epf->epc,
 					    ntb->epf->func_no,
@@ -557,14 +569,14 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 	return ret;
 
 err_alloc_peer_mem:
-	pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr, mw_addr, epf_bar->size);
+	pci_epf_free_space(ntb->epf, mw_addr, barno, 0);
 	return -1;
 }
 
 /**
  * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
  *   allocated in peer's outbound address space
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
 {
@@ -580,8 +592,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_mw_bar_init() - Configure Memory window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
 {
@@ -629,7 +642,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_mw_bar_clear() - Clear Memory window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
 {
@@ -652,7 +665,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces
  */
@@ -665,7 +678,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
 /**
  * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
  * constructs (scratchpad region, doorbell, memorywindow)
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
 {
@@ -706,11 +721,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_init() - Initialize NTB interface
- * @ntb: NTB device that facilitates communication between HOST and vHOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper to initialize a particular EPC interface and start the workqueue
- * to check for commands from host. This function will write to the
+ * to check for commands from HOST. This function will write to the
  * EP controller HW for configuring it.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_epc_init(struct epf_ntb *ntb)
 {
@@ -777,7 +794,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper to cleanup all NTB interfaces.
  */
@@ -934,6 +951,8 @@ static const struct config_item_type ntb_group_type = {
  *
  * Add configfs directory specific to NTB. This directory will hold
  * NTB specific properties like db_count, spad_count, num_mws etc.,
+ *
+ * Returns: Pointer to config_group
  */
 static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
 					    struct config_group *group)
@@ -1084,11 +1103,11 @@ static int vntb_epf_link_enable(struct ntb_dev *ntb,
 static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
-	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4;
+	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
 	u32 val;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
-	val = readl(base + off + ct + idx * 4);
+	val = readl(base + off + ct + idx * sizeof(u32));
 	return val;
 }
 
@@ -1096,10 +1115,10 @@ static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
-	int off = ctrl->spad_offset, ct = ctrl->spad_count * 4;
-	void __iomem *base = ntb->reg;
+	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
+	void __iomem *base = (void __iomem *)ntb->reg;
 
-	writel(val, base + off + ct + idx * 4);
+	writel(val, base + off + ct + idx * sizeof(u32));
 	return 0;
 }
 
@@ -1108,10 +1127,10 @@ static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 	u32 val;
 
-	val = readl(base + off + idx * 4);
+	val = readl(base + off + idx * sizeof(u32));
 	return val;
 }
 
@@ -1120,9 +1139,9 @@ static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
-	writel(val, base + off + idx * 4);
+	writel(val, base + off + idx * sizeof(u32));
 	return 0;
 }
 
@@ -1275,6 +1294,8 @@ static struct pci_driver vntb_pci_driver = {
  * Invoked when a primary interface or secondary interface is bound to EPC
  * device. This function will succeed only when EPC is bound to both the
  * interfaces.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_bind(struct pci_epf *epf)
 {
@@ -1359,6 +1380,8 @@ static struct pci_epf_ops epf_ntb_ops = {
  *
  * Probe NTB function driver when endpoint function bus detects a NTB
  * endpoint function.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_probe(struct pci_epf *epf)
 {
-- 
2.35.1

[PATCH v13 1/6] PCI: endpoint: pci-epf-vntb: Clean up kernel_doc warning

[Frank Li]

From: Frank Li <frank.li@nxp.com>

Cleanup warning found by scripts/kernel-doc
Consolidate term
    host, host1 to HOST
    vhost, vHost, Vhost, VHOST2 to VHOST

Signed-off-by: Frank Li <frank.li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 83 ++++++++++++-------
 1 file changed, 54 insertions(+), 29 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 0ea85e1d292e..c0115bcb3b5e 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -11,7 +11,7 @@
  * Author: Kishon Vijay Abraham I <kishon@ti.com>
  */
 
-/**
+/*
  * +------------+         +---------------------------------------+
  * |            |         |                                       |
  * +------------+         |                        +--------------+
@@ -156,12 +156,14 @@ static struct pci_epf_header epf_ntb_header = {
 };
 
 /**
- * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
+ * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
  * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @link_up: true or false indicating Link is UP or Down
  *
  * Once NTB function in HOST invoke ntb_link_enable(),
- * this NTB function driver will trigger a link event to vhost.
+ * this NTB function driver will trigger a link event to VHOST.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
 {
@@ -175,9 +177,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
 }
 
 /**
- * epf_ntb_configure_mw() - Configure the Outbound Address Space for vhost
- *   to access the memory window of host
- * @ntb: NTB device that facilitates communication between host and vhost
+ * epf_ntb_configure_mw() - Configure the Outbound Address Space for VHOST
+ *   to access the memory window of HOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @mw: Index of the memory window (either 0, 1, 2 or 3)
  *
  *                          EP Outbound Window
@@ -194,7 +196,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
  * |        |              |           |
  * |        |              |           |
  * +--------+              +-----------+
- *  VHost                   PCI EP
+ *  VHOST                   PCI EP
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
 {
@@ -219,7 +223,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
 
 /**
  * epf_ntb_teardown_mw() - Teardown the configured OB ATU
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @mw: Index of the memory window (either 0, 1, 2 or 3)
  *
  * Teardown the configured OB ATU configured in epf_ntb_configure_mw() using
@@ -234,12 +238,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb *ntb, u32 mw)
 }
 
 /**
- * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
+ * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
  * @work: work_struct for the epf_ntb_epc
  *
  * Workqueue function that gets invoked for the two epf_ntb_epc
  * periodically (once every 5ms) to see if it has received any commands
- * from NTB host. The host can send commands to configure doorbell or
+ * from NTB HOST. The HOST can send commands to configure doorbell or
  * configure memory window or to update link status.
  */
 static void epf_ntb_cmd_handler(struct work_struct *work)
@@ -321,8 +325,8 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 
 /**
  * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
- * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound
- *	     address.
+ * @ntb: EPC associated with one of the HOST which holds peer's outbound
+ *	 address.
  *
  * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
  * self scratchpad region (removes inbound ATU configuration). While BAR0 is
@@ -331,8 +335,10 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
  * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
  *
  * Please note the self scratchpad region and config region is combined to
- * a single region and mapped using the same BAR. Also note HOST2's peer
- * scratchpad is HOST1's self scratchpad.
+ * a single region and mapped using the same BAR. Also note VHOST's peer
+ * scratchpad is HOST's self scratchpad.
+ *
+ * Returns: void
  */
 static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
 {
@@ -347,13 +353,15 @@ static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
- * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
+ * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
  * self scratchpad region.
  *
  * Please note the self scratchpad region and config region is combined to
  * a single region and mapped using the same BAR.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
 {
@@ -380,7 +388,7 @@ static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
 /**
  * epf_ntb_config_spad_bar_free() - Free the physical memory associated with
  *   config + scratchpad region
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
 {
@@ -393,11 +401,13 @@ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
 /**
  * epf_ntb_config_spad_bar_alloc() - Allocate memory for config + scratchpad
  *   region
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Allocate the Local Memory mentioned in the above diagram. The size of
  * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD REGION
  * is obtained from "spad-count" configfs entry.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 {
@@ -465,11 +475,13 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 }
 
 /**
- * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Configure MSI/MSI-X capability for each interface with number of
  * interrupts equal to "db_count" configfs entry.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 {
@@ -511,7 +523,9 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_db_bar_init() - Configure Doorbell window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 {
@@ -566,7 +580,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb, int num_mws);
 /**
  * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
  *   allocated in peer's outbound address space
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
 {
@@ -582,8 +596,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_mw_bar_init() - Configure Memory window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
 {
@@ -639,7 +654,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_mw_bar_clear() - Clear Memory window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb, int num_mws)
 {
@@ -662,7 +677,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb, int num_mws)
 
 /**
  * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces
  */
@@ -675,7 +690,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
 /**
  * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
  * constructs (scratchpad region, doorbell, memorywindow)
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
 {
@@ -716,11 +733,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_init() - Initialize NTB interface
- * @ntb: NTB device that facilitates communication between HOST and vHOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper to initialize a particular EPC interface and start the workqueue
- * to check for commands from host. This function will write to the
+ * to check for commands from HOST. This function will write to the
  * EP controller HW for configuring it.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_epc_init(struct epf_ntb *ntb)
 {
@@ -787,7 +806,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper to cleanup all NTB interfaces.
  */
@@ -951,6 +970,8 @@ static const struct config_item_type ntb_group_type = {
  *
  * Add configfs directory specific to NTB. This directory will hold
  * NTB specific properties like db_count, spad_count, num_mws etc.,
+ *
+ * Returns: Pointer to config_group
  */
 static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
 					    struct config_group *group)
@@ -1292,6 +1313,8 @@ static struct pci_driver vntb_pci_driver = {
  * Invoked when a primary interface or secondary interface is bound to EPC
  * device. This function will succeed only when EPC is bound to both the
  * interfaces.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_bind(struct pci_epf *epf)
 {
@@ -1377,6 +1400,8 @@ static struct pci_epf_ops epf_ntb_ops = {
  *
  * Probe NTB function driver when endpoint function bus detects a NTB
  * endpoint function.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_probe(struct pci_epf *epf)
 {
-- 
2.34.1

[PATCH v13 2/6] PCI: endpoint: pci-epf-vntb: Fix indentation of the struct epf_ntb_ctrl

[Frank Li]

From: Frank Li <frank.li@nxp.com>

Indentation of the struct epf_ntb_ctrl align with other struct

Signed-off-by: Frank Li <frank.li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 28 +++++++++----------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index c0115bcb3b5e..1863006cc36c 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -99,20 +99,20 @@ enum epf_ntb_bar {
  *       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];
+	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 {
-- 
2.34.1

[PATCH v13 3/6] PCI: endpoint: pci-epf-vntb: fix call pci_epc_mem_free_addr at err path

[Frank Li]

From: Frank Li <frank.li@nxp.com>

Replace pci_epc_mem_free_addr() with pci_epf_free_space() at error handle
path to match pci_epf_alloc_space().

Signed-off-by: Frank Li <frank.li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 1863006cc36c..191924a83454 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -571,7 +571,7 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 	return ret;
 
 err_alloc_peer_mem:
-	pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr, mw_addr, epf_bar->size);
+	pci_epf_free_space(ntb->epf, mw_addr, barno, 0);
 	return -1;
 }
 
-- 
2.34.1

[PATCH v13 4/6] PCI: endpoint: pci-epf-vntb: remove unused field epf_db_phy

[Frank Li]

From: Frank Li <frank.li@nxp.com>

None use epf_db_phy and remove it.

Signed-off-by: Frank Li <frank.li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 191924a83454..ee66101cb5c4 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -136,7 +136,6 @@ struct epf_ntb {
 
 	struct epf_ntb_ctrl *reg;
 
-	phys_addr_t epf_db_phy;
 	void __iomem *epf_db;
 
 	phys_addr_t vpci_mw_phy[MAX_MW];
-- 
2.34.1

[PATCH v13 5/6] PCI: endpoint: pci-epf-vntb: replace hardcode 4 with sizeof(u32)

[Frank Li]

From: Frank Li <frank.li@nxp.com>

ntb span entry item size is sizeof(u32).

Signed-off-by: Frank Li <frank.li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 24 +++++++++----------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index ee66101cb5c4..54616281da9e 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -257,12 +257,12 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
 
 	for (i = 1; i < ntb->db_count; i++) {
-		if (readl(ntb->epf_db + i * 4)) {
-			if (readl(ntb->epf_db + i * 4))
+		if (readl(ntb->epf_db + i * sizeof(u32))) {
+			if (readl(ntb->epf_db + i * sizeof(u32)))
 				ntb->db |= 1 << (i - 1);
 
 			ntb_db_event(&ntb->ntb, i);
-			writel(0, ntb->epf_db + i * 4);
+			writel(0, ntb->epf_db + i * sizeof(u32));
 		}
 	}
 
@@ -433,7 +433,7 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 	spad_count = ntb->spad_count;
 
 	ctrl_size = sizeof(struct epf_ntb_ctrl);
-	spad_size = 2 * spad_count * 4;
+	spad_size = 2 * spad_count * sizeof(u32);
 
 	if (!align) {
 		ctrl_size = roundup_pow_of_two(ctrl_size);
@@ -463,7 +463,7 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 	ctrl->num_mws = ntb->num_mws;
 	ntb->spad_size = spad_size;
 
-	ctrl->db_entry_size = 4;
+	ctrl->db_entry_size = sizeof(u32);
 
 	for (i = 0; i < ntb->db_count; i++) {
 		ntb->reg->db_data[i] = 1 + i;
@@ -535,7 +535,7 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 	struct pci_epf_bar *epf_bar;
 	void __iomem *mw_addr;
 	enum pci_barno barno;
-	size_t size = 4 * ntb->db_count;
+	size_t size = sizeof(u32) * ntb->db_count;
 
 	epc_features = pci_epc_get_features(ntb->epf->epc,
 					    ntb->epf->func_no,
@@ -1121,11 +1121,11 @@ static int vntb_epf_link_enable(struct ntb_dev *ntb,
 static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
-	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4;
+	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
 	u32 val;
 	void __iomem *base = ntb->reg;
 
-	val = readl(base + off + ct + idx * 4);
+	val = readl(base + off + ct + idx * sizeof(u32));
 	return val;
 }
 
@@ -1133,10 +1133,10 @@ static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
-	int off = ctrl->spad_offset, ct = ctrl->spad_count * 4;
+	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
 	void __iomem *base = ntb->reg;
 
-	writel(val, base + off + ct + idx * 4);
+	writel(val, base + off + ct + idx * sizeof(u32));
 	return 0;
 }
 
@@ -1148,7 +1148,7 @@ static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx)
 	void __iomem *base = ntb->reg;
 	u32 val;
 
-	val = readl(base + off + idx * 4);
+	val = readl(base + off + idx * sizeof(u32));
 	return val;
 }
 
@@ -1159,7 +1159,7 @@ static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32
 	int off = ctrl->spad_offset;
 	void __iomem *base = ntb->reg;
 
-	writel(val, base + off + idx * 4);
+	writel(val, base + off + idx * sizeof(u32));
 	return 0;
 }
 
-- 
2.34.1

[PATCH v13 6/6] PCI: endpoint: pci-epf-vntb: fix sparse build warning

[Frank Li]

From: Frank Li <frank.li@nxp.com>

Using  epf_db[i] instead of readl() because epf_db is located in local
memory and allocated by dma_alloc_coherent().

Sparse build warning when there are not __iomem at readl().
Added __iomem force type convert in vntb_epf_peer_spad_read\write()
and vntb_epf_spad_read\write(). This require strong order at read and
write.

Signed-off-by: Frank Li <frank.li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 27 +++++++++----------
 1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 54616281da9e..9f1ec6788e51 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -136,7 +136,7 @@ struct epf_ntb {
 
 	struct epf_ntb_ctrl *reg;
 
-	void __iomem *epf_db;
+	u32 *epf_db;
 
 	phys_addr_t vpci_mw_phy[MAX_MW];
 	void __iomem *vpci_mw_addr[MAX_MW];
@@ -257,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
 
 	for (i = 1; i < ntb->db_count; i++) {
-		if (readl(ntb->epf_db + i * sizeof(u32))) {
-			if (readl(ntb->epf_db + i * sizeof(u32)))
-				ntb->db |= 1 << (i - 1);
-
+		if (ntb->epf_db[i]) {
 			ntb_db_event(&ntb->ntb, i);
-			writel(0, ntb->epf_db + i * sizeof(u32));
+			ntb->epf_db[i] = 0;
 		}
 	}
 
@@ -529,13 +526,15 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 {
 	const struct pci_epc_features *epc_features;
-	u32 align;
 	struct device *dev = &ntb->epf->dev;
-	int ret;
 	struct pci_epf_bar *epf_bar;
-	void __iomem *mw_addr;
 	enum pci_barno barno;
-	size_t size = sizeof(u32) * ntb->db_count;
+	void *mw_addr;
+	size_t size;
+	u32 align;
+	int ret;
+
+	size = sizeof(u32) * ntb->db_count;
 
 	epc_features = pci_epc_get_features(ntb->epf->epc,
 					    ntb->epf->func_no,
@@ -1123,7 +1122,7 @@ static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
 	u32 val;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
 	val = readl(base + off + ct + idx * sizeof(u32));
 	return val;
@@ -1134,7 +1133,7 @@ static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
 	writel(val, base + off + ct + idx * sizeof(u32));
 	return 0;
@@ -1145,7 +1144,7 @@ static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 	u32 val;
 
 	val = readl(base + off + idx * sizeof(u32));
@@ -1157,7 +1156,7 @@ static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
 	writel(val, base + off + idx * sizeof(u32));
 	return 0;
-- 
2.34.1

RE: [EXT] [PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

[Frank Li]

> -----Original Message-----
> From: Frank Li <Frank.Li@nxp.com>
> Sent: Friday, October 7, 2022 2:13 PM
> To: imx@lists.linux.dev; Jon Mason <jdmason@kudzu.us>; Dave Jiang
> <dave.jiang@intel.com>; Allen Hubbe <allenbh@gmail.com>; Kishon Vijay
> Abraham I <kishon@ti.com>; Lorenzo Pieralisi <lpieralisi@kernel.org>;
> Krzysztof Wilczyński <kw@linux.com>; Manivannan Sadhasivam
> <mani@kernel.org>; Bjorn Helgaas <bhelgaas@google.com>; open list:NTB
> DRIVER CORE <ntb@lists.linux.dev>; open list:PCI ENDPOINT SUBSYSTEM
> <linux-pci@vger.kernel.org>; open list <linux-kernel@vger.kernel.org>
> Subject: [EXT] [PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

[Frank Li] sorry! Please forget this patch, which below old series. 
Please check v13's patches.
 
> 
> Caution: EXT Email
> 
> Remove unused field: epf_db_phy.
> Remove __iomem before epf_db.
> Change epf_db to u32* from void *
> Remove duplicate check if (readl(ntb->epf_db + i * 4)).
> Using sizeof(u32) instead of number 4 at all place.
> 
> Clean up sparse build warning:
>   Using  epf_db[i] instead of readl() because epf_db is located in local
>   memory and allocated by dma_alloc_coherent(). Sparse build warning
> when
>   there are not __iomem at readl().
>   Added __iomem force type convert in vntb_epf_peer_spad_read\write()
> and
>   vntb_epf_spad_read\write(). This require strong order at read and write.
> 
> Replace pci_epc_mem_free_addr() with pci_epf_free_space() at error handle
> path to match pci_epf_alloc_space().
> 
> Cleanup warning found by scripts/kernel-doc
> Fix indentation of the struct epf_ntb_ctrl
> Consolidate term
>   host, host1 to HOST
>   vhost, vHost, Vhost, VHOST2 to VHOST
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/pci/endpoint/functions/pci-epf-vntb.c | 157 ++++++++++--------
>  1 file changed, 90 insertions(+), 67 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 1466dd1904175..acea753af29ed 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -11,7 +11,7 @@
>   * Author: Kishon Vijay Abraham I <kishon@ti.com>
>   */
> 
> -/**
> +/*
>   * +------------+         +---------------------------------------+
>   * |            |         |                                       |
>   * +------------+         |                        +--------------+
> @@ -99,20 +99,20 @@ enum epf_ntb_bar {
>   *       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];
> +       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 {
> @@ -136,8 +136,7 @@ struct epf_ntb {
> 
>         struct epf_ntb_ctrl *reg;
> 
> -       phys_addr_t epf_db_phy;
> -       void __iomem *epf_db;
> +       u32 *epf_db;
> 
>         phys_addr_t vpci_mw_phy[MAX_MW];
>         void __iomem *vpci_mw_addr[MAX_MW];
> @@ -156,12 +155,14 @@ static struct pci_epf_header epf_ntb_header = {
>  };
> 
>  /**
> - * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
> + * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
>   * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @link_up: true or false indicating Link is UP or Down
>   *
>   * Once NTB function in HOST invoke ntb_link_enable(),
> - * this NTB function driver will trigger a link event to vhost.
> + * this NTB function driver will trigger a link event to VHOST.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
>  {
> @@ -175,9 +176,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
>  }
> 
>  /**
> - * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> vhost
> - *   to access the memory window of host
> - * @ntb: NTB device that facilitates communication between host and vhost
> + * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> VHOST
> + *   to access the memory window of HOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @mw: Index of the memory window (either 0, 1, 2 or 3)
>   *
>   *                          EP Outbound Window
> @@ -194,7 +195,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
>   * |        |              |           |
>   * |        |              |           |
>   * +--------+              +-----------+
> - *  VHost                   PCI EP
> + *  VHOST                   PCI EP
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
>  {
> @@ -219,7 +222,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb,
> u32 mw)
> 
>  /**
>   * epf_ntb_teardown_mw() - Teardown the configured OB ATU
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @mw: Index of the memory window (either 0, 1, 2 or 3)
>   *
>   * Teardown the configured OB ATU configured in epf_ntb_configure_mw()
> using
> @@ -234,12 +237,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb
> *ntb, u32 mw)
>  }
> 
>  /**
> - * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
> + * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
>   * @work: work_struct for the epf_ntb_epc
>   *
>   * Workqueue function that gets invoked for the two epf_ntb_epc
>   * periodically (once every 5ms) to see if it has received any commands
> - * from NTB host. The host can send commands to configure doorbell or
> + * from NTB HOST. The HOST can send commands to configure doorbell or
>   * configure memory window or to update link status.
>   */
>  static void epf_ntb_cmd_handler(struct work_struct *work)
> @@ -254,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
>         ntb = container_of(work, struct epf_ntb, cmd_handler.work);
> 
>         for (i = 1; i < ntb->db_count; i++) {
> -               if (readl(ntb->epf_db + i * 4)) {
> -                       if (readl(ntb->epf_db + i * 4))
> -                               ntb->db |= 1 << (i - 1);
> -
> +               if (ntb->epf_db[i]) {
>                         ntb_db_event(&ntb->ntb, i);
> -                       writel(0, ntb->epf_db + i * 4);
> +                       ntb->epf_db[i] = 0;
>                 }
>         }
> 
> @@ -321,8 +321,8 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
> 
>  /**
>   * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
> - * @ntb_epc: EPC associated with one of the HOST which holds peer's
> outbound
> - *          address.
> + * @ntb: EPC associated with one of the HOST which holds peer's outbound
> + *      address.
>   *
>   * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
>   * self scratchpad region (removes inbound ATU configuration). While BAR0
> is
> @@ -331,8 +331,10 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
>   * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
>   *
>   * Please note the self scratchpad region and config region is combined to
> - * a single region and mapped using the same BAR. Also note HOST2's peer
> - * scratchpad is HOST1's self scratchpad.
> + * a single region and mapped using the same BAR. Also note VHOST's peer
> + * scratchpad is HOST's self scratchpad.
> + *
> + * Returns: void
>   */
>  static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -347,13 +349,15 @@ static void epf_ntb_config_sspad_bar_clear(struct
> epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
> - * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
> + * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
>   * self scratchpad region.
>   *
>   * Please note the self scratchpad region and config region is combined to
>   * a single region and mapped using the same BAR.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
>  {
> @@ -380,7 +384,7 @@ static int epf_ntb_config_sspad_bar_set(struct
> epf_ntb *ntb)
>  /**
>   * epf_ntb_config_spad_bar_free() - Free the physical memory associated
> with
>   *   config + scratchpad region
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
>  {
> @@ -393,11 +397,13 @@ static void epf_ntb_config_spad_bar_free(struct
> epf_ntb *ntb)
>  /**
>   * epf_ntb_config_spad_bar_alloc() - Allocate memory for config +
> scratchpad
>   *   region
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Allocate the Local Memory mentioned in the above diagram. The size of
>   * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD
> REGION
>   * is obtained from "spad-count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
>  {
> @@ -424,7 +430,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
>         spad_count = ntb->spad_count;
> 
>         ctrl_size = sizeof(struct epf_ntb_ctrl);
> -       spad_size = 2 * spad_count * 4;
> +       spad_size = 2 * spad_count * sizeof(u32);
> 
>         if (!align) {
>                 ctrl_size = roundup_pow_of_two(ctrl_size);
> @@ -454,7 +460,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
>         ctrl->num_mws = ntb->num_mws;
>         ntb->spad_size = spad_size;
> 
> -       ctrl->db_entry_size = 4;
> +       ctrl->db_entry_size = sizeof(u32);
> 
>         for (i = 0; i < ntb->db_count; i++) {
>                 ntb->reg->db_data[i] = 1 + i;
> @@ -465,11 +471,13 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
>  }
> 
>  /**
> - * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Configure MSI/MSI-X capability for each interface with number of
>   * interrupts equal to "db_count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
>  {
> @@ -511,18 +519,22 @@ static int epf_ntb_configure_interrupt(struct
> epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_db_bar_init() - Configure Doorbell window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
>  {
>         const struct pci_epc_features *epc_features;
> -       u32 align;
>         struct device *dev = &ntb->epf->dev;
> -       int ret;
>         struct pci_epf_bar *epf_bar;
> -       void __iomem *mw_addr;
>         enum pci_barno barno;
> -       size_t size = 4 * ntb->db_count;
> +       void *mw_addr;
> +       size_t size;
> +       u32 align;
> +       int ret;
> +
> +       size = sizeof(u32) * ntb->db_count;
> 
>         epc_features = pci_epc_get_features(ntb->epf->epc,
>                                             ntb->epf->func_no,
> @@ -557,14 +569,14 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
>         return ret;
> 
>  err_alloc_peer_mem:
> -       pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr, mw_addr,
> epf_bar->size);
> +       pci_epf_free_space(ntb->epf, mw_addr, barno, 0);
>         return -1;
>  }
> 
>  /**
>   * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
>   *   allocated in peer's outbound address space
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -580,8 +592,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_mw_bar_init() - Configure Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
>  {
> @@ -629,7 +642,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_mw_bar_clear() - Clear Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -652,7 +665,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb
> *ntb)
> 
>  /**
>   * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB
> interfaces
>   */
> @@ -665,7 +678,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
>  /**
>   * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
>   * constructs (scratchpad region, doorbell, memorywindow)
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
>  {
> @@ -706,11 +721,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_epc_init() - Initialize NTB interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper to initialize a particular EPC interface and start the workqueue
> - * to check for commands from host. This function will write to the
> + * to check for commands from HOST. This function will write to the
>   * EP controller HW for configuring it.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_epc_init(struct epf_ntb *ntb)
>  {
> @@ -777,7 +794,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper to cleanup all NTB interfaces.
>   */
> @@ -934,6 +951,8 @@ static const struct config_item_type ntb_group_type
> = {
>   *
>   * Add configfs directory specific to NTB. This directory will hold
>   * NTB specific properties like db_count, spad_count, num_mws etc.,
> + *
> + * Returns: Pointer to config_group
>   */
>  static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
>                                             struct config_group *group)
> @@ -1084,11 +1103,11 @@ static int vntb_epf_link_enable(struct ntb_dev
> *ntb,
>  static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
>  {
>         struct epf_ntb *ntb = ntb_ndev(ndev);
> -       int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4;
> +       int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
>         u32 val;
> -       void __iomem *base = ntb->reg;
> +       void __iomem *base = (void __iomem *)ntb->reg;
> 
> -       val = readl(base + off + ct + idx * 4);
> +       val = readl(base + off + ct + idx * sizeof(u32));
>         return val;
>  }
> 
> @@ -1096,10 +1115,10 @@ static int vntb_epf_spad_write(struct ntb_dev
> *ndev, int idx, u32 val)
>  {
>         struct epf_ntb *ntb = ntb_ndev(ndev);
>         struct epf_ntb_ctrl *ctrl = ntb->reg;
> -       int off = ctrl->spad_offset, ct = ctrl->spad_count * 4;
> -       void __iomem *base = ntb->reg;
> +       int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
> +       void __iomem *base = (void __iomem *)ntb->reg;
> 
> -       writel(val, base + off + ct + idx * 4);
> +       writel(val, base + off + ct + idx * sizeof(u32));
>         return 0;
>  }
> 
> @@ -1108,10 +1127,10 @@ static u32 vntb_epf_peer_spad_read(struct
> ntb_dev *ndev, int pidx, int idx)
>         struct epf_ntb *ntb = ntb_ndev(ndev);
>         struct epf_ntb_ctrl *ctrl = ntb->reg;
>         int off = ctrl->spad_offset;
> -       void __iomem *base = ntb->reg;
> +       void __iomem *base = (void __iomem *)ntb->reg;
>         u32 val;
> 
> -       val = readl(base + off + idx * 4);
> +       val = readl(base + off + idx * sizeof(u32));
>         return val;
>  }
> 
> @@ -1120,9 +1139,9 @@ static int vntb_epf_peer_spad_write(struct
> ntb_dev *ndev, int pidx, int idx, u32
>         struct epf_ntb *ntb = ntb_ndev(ndev);
>         struct epf_ntb_ctrl *ctrl = ntb->reg;
>         int off = ctrl->spad_offset;
> -       void __iomem *base = ntb->reg;
> +       void __iomem *base = (void __iomem *)ntb->reg;
> 
> -       writel(val, base + off + idx * 4);
> +       writel(val, base + off + idx * sizeof(u32));
>         return 0;
>  }
> 
> @@ -1275,6 +1294,8 @@ static struct pci_driver vntb_pci_driver = {
>   * Invoked when a primary interface or secondary interface is bound to EPC
>   * device. This function will succeed only when EPC is bound to both the
>   * interfaces.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_bind(struct pci_epf *epf)
>  {
> @@ -1359,6 +1380,8 @@ static struct pci_epf_ops epf_ntb_ops = {
>   *
>   * Probe NTB function driver when endpoint function bus detects a NTB
>   * endpoint function.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_probe(struct pci_epf *epf)
>  {
> --
> 2.35.1

RE: [PATCH v13 1/6] PCI: endpoint: pci-epf-vntb: Clean up kernel_doc warning

[Frank Li]

> -----Original Message-----
> From: Frank Li
> Sent: Friday, October 7, 2022 2:14 PM
> To: imx@lists.linux.dev; Jon Mason <jdmason@kudzu.us>; Dave Jiang
> <dave.jiang@intel.com>; Allen Hubbe <allenbh@gmail.com>; Kishon Vijay
> Abraham I <kishon@ti.com>; Lorenzo Pieralisi <lpieralisi@kernel.org>;
> Krzysztof Wilczyński <kw@linux.com>; Manivannan Sadhasivam
> <mani@kernel.org>; Bjorn Helgaas <bhelgaas@google.com>; open list:NTB
> DRIVER CORE <ntb@lists.linux.dev>; open list:PCI ENDPOINT SUBSYSTEM
> <linux-pci@vger.kernel.org>; open list <linux-kernel@vger.kernel.org>
> Subject: [PATCH v13 1/6] PCI: endpoint: pci-epf-vntb: Clean up kernel_doc
> warning

[Frank Li] Friendly ping.  

> 
> From: Frank Li <frank.li@nxp.com>
> 
> Cleanup warning found by scripts/kernel-doc
> Consolidate term
>     host, host1 to HOST
>     vhost, vHost, Vhost, VHOST2 to VHOST
> 
> Signed-off-by: Frank Li <frank.li@nxp.com>
> ---
>  drivers/pci/endpoint/functions/pci-epf-vntb.c | 83 ++++++++++++-------
>  1 file changed, 54 insertions(+), 29 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 0ea85e1d292e..c0115bcb3b5e 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -11,7 +11,7 @@
>   * Author: Kishon Vijay Abraham I <kishon@ti.com>
>   */
> 
> -/**
> +/*
>   * +------------+         +---------------------------------------+
>   * |            |         |                                       |
>   * +------------+         |                        +--------------+
> @@ -156,12 +156,14 @@ static struct pci_epf_header epf_ntb_header = {
>  };
> 
>  /**
> - * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
> + * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
>   * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @link_up: true or false indicating Link is UP or Down
>   *
>   * Once NTB function in HOST invoke ntb_link_enable(),
> - * this NTB function driver will trigger a link event to vhost.
> + * this NTB function driver will trigger a link event to VHOST.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
>  {
> @@ -175,9 +177,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
>  }
> 
>  /**
> - * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> vhost
> - *   to access the memory window of host
> - * @ntb: NTB device that facilitates communication between host and vhost
> + * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> VHOST
> + *   to access the memory window of HOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @mw: Index of the memory window (either 0, 1, 2 or 3)
>   *
>   *                          EP Outbound Window
> @@ -194,7 +196,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
>   * |        |              |           |
>   * |        |              |           |
>   * +--------+              +-----------+
> - *  VHost                   PCI EP
> + *  VHOST                   PCI EP
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
>  {
> @@ -219,7 +223,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb,
> u32 mw)
> 
>  /**
>   * epf_ntb_teardown_mw() - Teardown the configured OB ATU
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @mw: Index of the memory window (either 0, 1, 2 or 3)
>   *
>   * Teardown the configured OB ATU configured in epf_ntb_configure_mw()
> using
> @@ -234,12 +238,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb
> *ntb, u32 mw)
>  }
> 
>  /**
> - * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
> + * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
>   * @work: work_struct for the epf_ntb_epc
>   *
>   * Workqueue function that gets invoked for the two epf_ntb_epc
>   * periodically (once every 5ms) to see if it has received any commands
> - * from NTB host. The host can send commands to configure doorbell or
> + * from NTB HOST. The HOST can send commands to configure doorbell or
>   * configure memory window or to update link status.
>   */
>  static void epf_ntb_cmd_handler(struct work_struct *work)
> @@ -321,8 +325,8 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
> 
>  /**
>   * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
> - * @ntb_epc: EPC associated with one of the HOST which holds peer's
> outbound
> - *	     address.
> + * @ntb: EPC associated with one of the HOST which holds peer's outbound
> + *	 address.
>   *
>   * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
>   * self scratchpad region (removes inbound ATU configuration). While BAR0
> is
> @@ -331,8 +335,10 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
>   * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
>   *
>   * Please note the self scratchpad region and config region is combined to
> - * a single region and mapped using the same BAR. Also note HOST2's peer
> - * scratchpad is HOST1's self scratchpad.
> + * a single region and mapped using the same BAR. Also note VHOST's peer
> + * scratchpad is HOST's self scratchpad.
> + *
> + * Returns: void
>   */
>  static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -347,13 +353,15 @@ static void epf_ntb_config_sspad_bar_clear(struct
> epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
> - * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
> + * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
>   * self scratchpad region.
>   *
>   * Please note the self scratchpad region and config region is combined to
>   * a single region and mapped using the same BAR.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
>  {
> @@ -380,7 +388,7 @@ static int epf_ntb_config_sspad_bar_set(struct
> epf_ntb *ntb)
>  /**
>   * epf_ntb_config_spad_bar_free() - Free the physical memory associated
> with
>   *   config + scratchpad region
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
>  {
> @@ -393,11 +401,13 @@ static void epf_ntb_config_spad_bar_free(struct
> epf_ntb *ntb)
>  /**
>   * epf_ntb_config_spad_bar_alloc() - Allocate memory for config +
> scratchpad
>   *   region
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Allocate the Local Memory mentioned in the above diagram. The size of
>   * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD
> REGION
>   * is obtained from "spad-count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
>  {
> @@ -465,11 +475,13 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
>  }
> 
>  /**
> - * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Configure MSI/MSI-X capability for each interface with number of
>   * interrupts equal to "db_count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
>  {
> @@ -511,7 +523,9 @@ static int epf_ntb_configure_interrupt(struct epf_ntb
> *ntb)
> 
>  /**
>   * epf_ntb_db_bar_init() - Configure Doorbell window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
>  {
> @@ -566,7 +580,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb
> *ntb, int num_mws);
>  /**
>   * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
>   *   allocated in peer's outbound address space
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -582,8 +596,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_mw_bar_init() - Configure Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
>  {
> @@ -639,7 +654,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_mw_bar_clear() - Clear Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb, int num_mws)
>  {
> @@ -662,7 +677,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb
> *ntb, int num_mws)
> 
>  /**
>   * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB
> interfaces
>   */
> @@ -675,7 +690,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
>  /**
>   * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
>   * constructs (scratchpad region, doorbell, memorywindow)
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
>  {
> @@ -716,11 +733,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_epc_init() - Initialize NTB interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper to initialize a particular EPC interface and start the workqueue
> - * to check for commands from host. This function will write to the
> + * to check for commands from HOST. This function will write to the
>   * EP controller HW for configuring it.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_epc_init(struct epf_ntb *ntb)
>  {
> @@ -787,7 +806,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper to cleanup all NTB interfaces.
>   */
> @@ -951,6 +970,8 @@ static const struct config_item_type ntb_group_type
> = {
>   *
>   * Add configfs directory specific to NTB. This directory will hold
>   * NTB specific properties like db_count, spad_count, num_mws etc.,
> + *
> + * Returns: Pointer to config_group
>   */
>  static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
>  					    struct config_group *group)
> @@ -1292,6 +1313,8 @@ static struct pci_driver vntb_pci_driver = {
>   * Invoked when a primary interface or secondary interface is bound to EPC
>   * device. This function will succeed only when EPC is bound to both the
>   * interfaces.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_bind(struct pci_epf *epf)
>  {
> @@ -1377,6 +1400,8 @@ static struct pci_epf_ops epf_ntb_ops = {
>   *
>   * Probe NTB function driver when endpoint function bus detects a NTB
>   * endpoint function.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_probe(struct pci_epf *epf)
>  {
> --
> 2.34.1

Re: [PATCH v13 1/6] PCI: endpoint: pci-epf-vntb: Clean up kernel_doc warning

[Bjorn Helgaas]

On Fri, Oct 07, 2022 at 03:13:21PM -0400, Frank Li wrote:
> From: Frank Li <frank.li@nxp.com>
> 
> Cleanup warning found by scripts/kernel-doc
> Consolidate term
>     host, host1 to HOST
>     vhost, vHost, Vhost, VHOST2 to VHOST

When you post a series of several patches, it's nice if you include a
[0/n] cover letter to tie them all together.  Regrettably, this is not
very well covered in the documentation, but here's a pointer:

  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/5.Posting.rst?id=v6.0#n334

And if you look at the archives, you'll see lots of examples:

  https://lore.kernel.org/linux-pci/

RE: [EXT] Re: [PATCH v13 1/6] PCI: endpoint: pci-epf-vntb: Clean up kernel_doc warning

[Frank Li]

> -----Original Message-----
> From: Bjorn Helgaas <helgaas@kernel.org>
> Sent: Wednesday, October 19, 2022 11:26 AM
> To: Frank Li <frank.li@nxp.com>
> Cc: imx@lists.linux.dev; Jon Mason <jdmason@kudzu.us>; Dave Jiang
> <dave.jiang@intel.com>; Allen Hubbe <allenbh@gmail.com>; Kishon Vijay
> Abraham I <kishon@ti.com>; Lorenzo Pieralisi <lpieralisi@kernel.org>;
> Krzysztof Wilczyński <kw@linux.com>; Manivannan Sadhasivam
> <mani@kernel.org>; Bjorn Helgaas <bhelgaas@google.com>; open list:NTB
> DRIVER CORE <ntb@lists.linux.dev>; open list:PCI ENDPOINT SUBSYSTEM
> <linux-pci@vger.kernel.org>; open list <linux-kernel@vger.kernel.org>
> Subject: [EXT] Re: [PATCH v13 1/6] PCI: endpoint: pci-epf-vntb: Clean up
> kernel_doc warning
> 
> Caution: EXT Email
> 
> On Fri, Oct 07, 2022 at 03:13:21PM -0400, Frank Li wrote:
> > From: Frank Li <frank.li@nxp.com>
> >
> > Cleanup warning found by scripts/kernel-doc
> > Consolidate term
> >     host, host1 to HOST
> >     vhost, vHost, Vhost, VHOST2 to VHOST
> 
> When you post a series of several patches, it's nice if you include a
> [0/n] cover letter to tie them all together.  Regrettably, this is not
> very well covered in the documentation, but here's a pointer:

[Frank Li] Strange, cover letter missed in PCI mail list.  Let me repost it.

> 
> 
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit.ker
> nel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Ftorvalds%2Flinux.git%2F
> tree%2FDocumentation%2Fprocess%2F5.Posting.rst%3Fid%3Dv6.0%23n334&
> amp;data=05%7C01%7CFrank.Li%40nxp.com%7C02ecb68ec2024b8ad43208d
> ab1ee9c8d%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6380179
> 35642690987%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQ
> IjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;
> sdata=%2BgCDqyYli65%2FVW7eUAC8ZrSAprNVa2QhqcCChsZCF0w%3D&amp
> ;reserved=0
> 
> And if you look at the archives, you'll see lots of examples:
> 
> 
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.k
> ernel.org%2Flinux-
> pci%2F&amp;data=05%7C01%7CFrank.Li%40nxp.com%7C02ecb68ec2024b8a
> d43208dab1ee9c8d%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C
> 638017935642690987%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwM
> DAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7
> C&amp;sdata=FG4SbxNVF66T8ka82DJdB2JmyOeQbyAIstINr%2Bp8UQg%3D&
> amp;reserved=0

Re: [PATCH v13 6/6] PCI: endpoint: pci-epf-vntb: fix sparse build warning

[Lorenzo Pieralisi]

On Fri, Oct 07, 2022 at 03:13:26PM -0400, Frank Li wrote:
> From: Frank Li <frank.li@nxp.com>
> 
> Using  epf_db[i] instead of readl() because epf_db is located in local
> memory and allocated by dma_alloc_coherent().
> 
> Sparse build warning when there are not __iomem at readl().
> Added __iomem force type convert in vntb_epf_peer_spad_read\write()
> and vntb_epf_spad_read\write(). This require strong order at read and
> write.

This commit log is unreadable sorry and this patch fixes multiple things
and even rearrange local variables in a way that is completely
unrelated to the patch aim itself.

If you are fixing sparse warning reports the warnings and fix them
one by one.

Could you please pay attention to these details ? I don't have time
to do it for you, sorry.

Thanks,
Lorenzo

> Signed-off-by: Frank Li <frank.li@nxp.com>
> ---
>  drivers/pci/endpoint/functions/pci-epf-vntb.c | 27 +++++++++----------
>  1 file changed, 13 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 54616281da9e..9f1ec6788e51 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -136,7 +136,7 @@ struct epf_ntb {
>  
>  	struct epf_ntb_ctrl *reg;
>  
> -	void __iomem *epf_db;
> +	u32 *epf_db;
>  
>  	phys_addr_t vpci_mw_phy[MAX_MW];
>  	void __iomem *vpci_mw_addr[MAX_MW];
> @@ -257,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
>  	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
>  
>  	for (i = 1; i < ntb->db_count; i++) {
> -		if (readl(ntb->epf_db + i * sizeof(u32))) {
> -			if (readl(ntb->epf_db + i * sizeof(u32)))
> -				ntb->db |= 1 << (i - 1);
> -
> +		if (ntb->epf_db[i]) {
>  			ntb_db_event(&ntb->ntb, i);
> -			writel(0, ntb->epf_db + i * sizeof(u32));
> +			ntb->epf_db[i] = 0;
>  		}
>  	}
>  
> @@ -529,13 +526,15 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
>  static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
>  {
>  	const struct pci_epc_features *epc_features;
> -	u32 align;
>  	struct device *dev = &ntb->epf->dev;
> -	int ret;
>  	struct pci_epf_bar *epf_bar;
> -	void __iomem *mw_addr;
>  	enum pci_barno barno;
> -	size_t size = sizeof(u32) * ntb->db_count;
> +	void *mw_addr;
> +	size_t size;
> +	u32 align;
> +	int ret;
> +
> +	size = sizeof(u32) * ntb->db_count;
>  
>  	epc_features = pci_epc_get_features(ntb->epf->epc,
>  					    ntb->epf->func_no,
> @@ -1123,7 +1122,7 @@ static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
>  	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
>  	u32 val;
> -	void __iomem *base = ntb->reg;
> +	void __iomem *base = (void __iomem *)ntb->reg;
>  
>  	val = readl(base + off + ct + idx * sizeof(u32));
>  	return val;
> @@ -1134,7 +1133,7 @@ static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val)
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
>  	struct epf_ntb_ctrl *ctrl = ntb->reg;
>  	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
> -	void __iomem *base = ntb->reg;
> +	void __iomem *base = (void __iomem *)ntb->reg;
>  
>  	writel(val, base + off + ct + idx * sizeof(u32));
>  	return 0;
> @@ -1145,7 +1144,7 @@ static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx)
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
>  	struct epf_ntb_ctrl *ctrl = ntb->reg;
>  	int off = ctrl->spad_offset;
> -	void __iomem *base = ntb->reg;
> +	void __iomem *base = (void __iomem *)ntb->reg;
>  	u32 val;
>  
>  	val = readl(base + off + idx * sizeof(u32));
> @@ -1157,7 +1156,7 @@ static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
>  	struct epf_ntb_ctrl *ctrl = ntb->reg;
>  	int off = ctrl->spad_offset;
> -	void __iomem *base = ntb->reg;
> +	void __iomem *base = (void __iomem *)ntb->reg;
>  
>  	writel(val, base + off + idx * sizeof(u32));
>  	return 0;
> -- 
> 2.34.1
> 

RE: [EXT] Re: [PATCH v13 6/6] PCI: endpoint: pci-epf-vntb: fix sparse build warning

[Frank Li]

> -----Original Message-----
> From: Lorenzo Pieralisi <lpieralisi@kernel.org>
> Sent: Thursday, October 27, 2022 5:43 AM
> To: Frank Li <frank.li@nxp.com>
> Cc: imx@lists.linux.dev; Jon Mason <jdmason@kudzu.us>; Dave Jiang
> <dave.jiang@intel.com>; Allen Hubbe <allenbh@gmail.com>; Kishon Vijay
> Abraham I <kishon@ti.com>; Krzysztof Wilczyński <kw@linux.com>;
> Manivannan Sadhasivam <mani@kernel.org>; Bjorn Helgaas
> <bhelgaas@google.com>; open list:NTB DRIVER CORE <ntb@lists.linux.dev>;
> open list:PCI ENDPOINT SUBSYSTEM <linux-pci@vger.kernel.org>; open list
> <linux-kernel@vger.kernel.org>
> Subject: [EXT] Re: [PATCH v13 6/6] PCI: endpoint: pci-epf-vntb: fix sparse
> build warning
> 
> Caution: EXT Email
> 
> On Fri, Oct 07, 2022 at 03:13:26PM -0400, Frank Li wrote:
> > From: Frank Li <frank.li@nxp.com>
> >
> > Using  epf_db[i] instead of readl() because epf_db is located in local
> > memory and allocated by dma_alloc_coherent().
> >
> > Sparse build warning when there are not __iomem at readl().
> > Added __iomem force type convert in vntb_epf_peer_spad_read\write()
> > and vntb_epf_spad_read\write(). This require strong order at read and
> > write.
> 
> This commit log is unreadable sorry and this patch fixes multiple things
> and even rearrange local variables in a way that is completely
> unrelated to the patch aim itself.

[Frank Li] Not everyone is English native speaker.  If you think it is bad, 
Please give me what you want to change to? 

Abut rearrange local variable, It is my fault when split patch. 

> 
> If you are fixing sparse warning reports the warnings and fix them
> one by one.

[Frank Li] Error in vntb_epf_peer_spad_write is the same as vntb_epf_peer_spad_read
All are the same type error. Did you still prefer fixed one by one? 

> 
> Could you please pay attention to these details ? I don't have time
> to do it for you, sorry.

[Frank Li] Do you have other comments about other patches? 

> 
> Thanks,
> Lorenzo
> 
> > Signed-off-by: Frank Li <frank.li@nxp.com>
> > ---
> >  drivers/pci/endpoint/functions/pci-epf-vntb.c | 27 +++++++++----------
> >  1 file changed, 13 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> > index 54616281da9e..9f1ec6788e51 100644
> > --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> > +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> > @@ -136,7 +136,7 @@ struct epf_ntb {
> >
> >       struct epf_ntb_ctrl *reg;
> >
> > -     void __iomem *epf_db;
> > +     u32 *epf_db;
> >
> >       phys_addr_t vpci_mw_phy[MAX_MW];
> >       void __iomem *vpci_mw_addr[MAX_MW];
> > @@ -257,12 +257,9 @@ static void epf_ntb_cmd_handler(struct
> work_struct *work)
> >       ntb = container_of(work, struct epf_ntb, cmd_handler.work);
> >
> >       for (i = 1; i < ntb->db_count; i++) {
> > -             if (readl(ntb->epf_db + i * sizeof(u32))) {
> > -                     if (readl(ntb->epf_db + i * sizeof(u32)))
> > -                             ntb->db |= 1 << (i - 1);
> > -
> > +             if (ntb->epf_db[i]) {
> >                       ntb_db_event(&ntb->ntb, i);
> > -                     writel(0, ntb->epf_db + i * sizeof(u32));
> > +                     ntb->epf_db[i] = 0;
> >               }
> >       }
> >
> > @@ -529,13 +526,15 @@ static int epf_ntb_configure_interrupt(struct
> epf_ntb *ntb)
> >  static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
> >  {
> >       const struct pci_epc_features *epc_features;
> > -     u32 align;
> >       struct device *dev = &ntb->epf->dev;
> > -     int ret;
> >       struct pci_epf_bar *epf_bar;
> > -     void __iomem *mw_addr;
> >       enum pci_barno barno;
> > -     size_t size = sizeof(u32) * ntb->db_count;
> > +     void *mw_addr;
> > +     size_t size;
> > +     u32 align;
> > +     int ret;
> > +
> > +     size = sizeof(u32) * ntb->db_count;
> >
> >       epc_features = pci_epc_get_features(ntb->epf->epc,
> >                                           ntb->epf->func_no,
> > @@ -1123,7 +1122,7 @@ static u32 vntb_epf_spad_read(struct ntb_dev
> *ndev, int idx)
> >       struct epf_ntb *ntb = ntb_ndev(ndev);
> >       int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
> >       u32 val;
> > -     void __iomem *base = ntb->reg;
> > +     void __iomem *base = (void __iomem *)ntb->reg;
> >
> >       val = readl(base + off + ct + idx * sizeof(u32));
> >       return val;
> > @@ -1134,7 +1133,7 @@ static int vntb_epf_spad_write(struct ntb_dev
> *ndev, int idx, u32 val)
> >       struct epf_ntb *ntb = ntb_ndev(ndev);
> >       struct epf_ntb_ctrl *ctrl = ntb->reg;
> >       int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
> > -     void __iomem *base = ntb->reg;
> > +     void __iomem *base = (void __iomem *)ntb->reg;
> >
> >       writel(val, base + off + ct + idx * sizeof(u32));
> >       return 0;
> > @@ -1145,7 +1144,7 @@ static u32 vntb_epf_peer_spad_read(struct
> ntb_dev *ndev, int pidx, int idx)
> >       struct epf_ntb *ntb = ntb_ndev(ndev);
> >       struct epf_ntb_ctrl *ctrl = ntb->reg;
> >       int off = ctrl->spad_offset;
> > -     void __iomem *base = ntb->reg;
> > +     void __iomem *base = (void __iomem *)ntb->reg;
> >       u32 val;
> >
> >       val = readl(base + off + idx * sizeof(u32));
> > @@ -1157,7 +1156,7 @@ static int vntb_epf_peer_spad_write(struct
> ntb_dev *ndev, int pidx, int idx, u32
> >       struct epf_ntb *ntb = ntb_ndev(ndev);
> >       struct epf_ntb_ctrl *ctrl = ntb->reg;
> >       int off = ctrl->spad_offset;
> > -     void __iomem *base = ntb->reg;
> > +     void __iomem *base = (void __iomem *)ntb->reg;
> >
> >       writel(val, base + off + idx * sizeof(u32));
> >       return 0;
> > --
> > 2.34.1
> >

Re: [PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

[Lorenzo Pieralisi]

On Thu, Oct 06, 2022 at 02:25:01PM +0000, Frank Li wrote:

[...]

> [Frank Li] @Bjorn Helgaas, ping
> Patches[1-4] was already picked  by irqchip. 
> I think patch[5-6] should go through pci subsystem. 
> Any additional comments?

Yes. Don't mix clean-ups with new features. This patch
should be split it does too many things at once, group
the clean ups in different patches and send them as
a separate series.

Lorenzo

> > Remove unused field: epf_db_phy.
> > Remove __iomem before epf_db.
> > Change epf_db to u32* from void *
> > Remove duplicate check if (readl(ntb->epf_db + i * 4)).
> > Using sizeof(u32) instead of number 4 at all place.
> > 
> > Clean up sparse build warning:
> >   Using  epf_db[i] instead of readl() because epf_db is located in local
> >   memory and allocated by dma_alloc_coherent(). Sparse build warning
> > when
> >   there are not __iomem at readl().
> >   Added __iomem force type convert in vntb_epf_peer_spad_read\write()
> > and
> >   vntb_epf_spad_read\write(). This require strong order at read and write.
> > 
> > Replace pci_epc_mem_free_addr() with pci_epf_free_space() at error handle
> > path to match pci_epf_alloc_space().
> > 
> > Cleanup warning found by scripts/kernel-doc
> > Fix indentation of the struct epf_ntb_ctrl
> > Consolidate term
> >   host, host1 to HOST
> >   vhost, vHost, Vhost, VHOST2 to VHOST
> > 
> > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > ---
> >  drivers/pci/endpoint/functions/pci-epf-vntb.c | 157 ++++++++++--------
> >  1 file changed, 90 insertions(+), 67 deletions(-)
> > 
> > diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> > b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> > index 1466dd1904175..acea753af29ed 100644
> > --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> > +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> > @@ -11,7 +11,7 @@
> >   * Author: Kishon Vijay Abraham I <kishon@ti.com>
> >   */
> > 
> > -/**
> > +/*
> >   * +------------+         +---------------------------------------+
> >   * |            |         |                                       |
> >   * +------------+         |                        +--------------+
> > @@ -99,20 +99,20 @@ enum epf_ntb_bar {
> >   *       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];
> > +	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 {
> > @@ -136,8 +136,7 @@ struct epf_ntb {
> > 
> >  	struct epf_ntb_ctrl *reg;
> > 
> > -	phys_addr_t epf_db_phy;
> > -	void __iomem *epf_db;
> > +	u32 *epf_db;
> > 
> >  	phys_addr_t vpci_mw_phy[MAX_MW];
> >  	void __iomem *vpci_mw_addr[MAX_MW];
> > @@ -156,12 +155,14 @@ static struct pci_epf_header epf_ntb_header = {
> >  };
> > 
> >  /**
> > - * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
> > + * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
> >   * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   * @link_up: true or false indicating Link is UP or Down
> >   *
> >   * Once NTB function in HOST invoke ntb_link_enable(),
> > - * this NTB function driver will trigger a link event to vhost.
> > + * this NTB function driver will trigger a link event to VHOST.
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
> >  {
> > @@ -175,9 +176,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> > link_up)
> >  }
> > 
> >  /**
> > - * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> > vhost
> > - *   to access the memory window of host
> > - * @ntb: NTB device that facilitates communication between host and vhost
> > + * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> > VHOST
> > + *   to access the memory window of HOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   * @mw: Index of the memory window (either 0, 1, 2 or 3)
> >   *
> >   *                          EP Outbound Window
> > @@ -194,7 +195,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> > link_up)
> >   * |        |              |           |
> >   * |        |              |           |
> >   * +--------+              +-----------+
> > - *  VHost                   PCI EP
> > + *  VHOST                   PCI EP
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
> >  {
> > @@ -219,7 +222,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb,
> > u32 mw)
> > 
> >  /**
> >   * epf_ntb_teardown_mw() - Teardown the configured OB ATU
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   * @mw: Index of the memory window (either 0, 1, 2 or 3)
> >   *
> >   * Teardown the configured OB ATU configured in epf_ntb_configure_mw()
> > using
> > @@ -234,12 +237,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb
> > *ntb, u32 mw)
> >  }
> > 
> >  /**
> > - * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
> > + * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
> >   * @work: work_struct for the epf_ntb_epc
> >   *
> >   * Workqueue function that gets invoked for the two epf_ntb_epc
> >   * periodically (once every 5ms) to see if it has received any commands
> > - * from NTB host. The host can send commands to configure doorbell or
> > + * from NTB HOST. The HOST can send commands to configure doorbell or
> >   * configure memory window or to update link status.
> >   */
> >  static void epf_ntb_cmd_handler(struct work_struct *work)
> > @@ -254,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct
> > *work)
> >  	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
> > 
> >  	for (i = 1; i < ntb->db_count; i++) {
> > -		if (readl(ntb->epf_db + i * 4)) {
> > -			if (readl(ntb->epf_db + i * 4))
> > -				ntb->db |= 1 << (i - 1);
> > -
> > +		if (ntb->epf_db[i]) {
> >  			ntb_db_event(&ntb->ntb, i);
> > -			writel(0, ntb->epf_db + i * 4);
> > +			ntb->epf_db[i] = 0;
> >  		}
> >  	}
> > 
> > @@ -321,8 +321,8 @@ static void epf_ntb_cmd_handler(struct work_struct
> > *work)
> > 
> >  /**
> >   * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
> > - * @ntb_epc: EPC associated with one of the HOST which holds peer's
> > outbound
> > - *	     address.
> > + * @ntb: EPC associated with one of the HOST which holds peer's outbound
> > + *	 address.
> >   *
> >   * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
> >   * self scratchpad region (removes inbound ATU configuration). While BAR0
> > is
> > @@ -331,8 +331,10 @@ static void epf_ntb_cmd_handler(struct work_struct
> > *work)
> >   * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
> >   *
> >   * Please note the self scratchpad region and config region is combined to
> > - * a single region and mapped using the same BAR. Also note HOST2's peer
> > - * scratchpad is HOST1's self scratchpad.
> > + * a single region and mapped using the same BAR. Also note VHOST's peer
> > + * scratchpad is HOST's self scratchpad.
> > + *
> > + * Returns: void
> >   */
> >  static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
> >  {
> > @@ -347,13 +349,15 @@ static void epf_ntb_config_sspad_bar_clear(struct
> > epf_ntb *ntb)
> > 
> >  /**
> >   * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   *
> > - * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
> > + * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
> >   * self scratchpad region.
> >   *
> >   * Please note the self scratchpad region and config region is combined to
> >   * a single region and mapped using the same BAR.
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
> >  {
> > @@ -380,7 +384,7 @@ static int epf_ntb_config_sspad_bar_set(struct
> > epf_ntb *ntb)
> >  /**
> >   * epf_ntb_config_spad_bar_free() - Free the physical memory associated
> > with
> >   *   config + scratchpad region
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   */
> >  static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
> >  {
> > @@ -393,11 +397,13 @@ static void epf_ntb_config_spad_bar_free(struct
> > epf_ntb *ntb)
> >  /**
> >   * epf_ntb_config_spad_bar_alloc() - Allocate memory for config +
> > scratchpad
> >   *   region
> > - * @ntb: NTB device that facilitates communication between HOST1 and
> > HOST2
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   *
> >   * Allocate the Local Memory mentioned in the above diagram. The size of
> >   * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD
> > REGION
> >   * is obtained from "spad-count" configfs entry.
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
> >  {
> > @@ -424,7 +430,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> > epf_ntb *ntb)
> >  	spad_count = ntb->spad_count;
> > 
> >  	ctrl_size = sizeof(struct epf_ntb_ctrl);
> > -	spad_size = 2 * spad_count * 4;
> > +	spad_size = 2 * spad_count * sizeof(u32);
> > 
> >  	if (!align) {
> >  		ctrl_size = roundup_pow_of_two(ctrl_size);
> > @@ -454,7 +460,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> > epf_ntb *ntb)
> >  	ctrl->num_mws = ntb->num_mws;
> >  	ntb->spad_size = spad_size;
> > 
> > -	ctrl->db_entry_size = 4;
> > +	ctrl->db_entry_size = sizeof(u32);
> > 
> >  	for (i = 0; i < ntb->db_count; i++) {
> >  		ntb->reg->db_data[i] = 1 + i;
> > @@ -465,11 +471,13 @@ static int epf_ntb_config_spad_bar_alloc(struct
> > epf_ntb *ntb)
> >  }
> > 
> >  /**
> > - * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   *
> >   * Configure MSI/MSI-X capability for each interface with number of
> >   * interrupts equal to "db_count" configfs entry.
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
> >  {
> > @@ -511,18 +519,22 @@ static int epf_ntb_configure_interrupt(struct
> > epf_ntb *ntb)
> > 
> >  /**
> >   * epf_ntb_db_bar_init() - Configure Doorbell window BARs
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
> >  {
> >  	const struct pci_epc_features *epc_features;
> > -	u32 align;
> >  	struct device *dev = &ntb->epf->dev;
> > -	int ret;
> >  	struct pci_epf_bar *epf_bar;
> > -	void __iomem *mw_addr;
> >  	enum pci_barno barno;
> > -	size_t size = 4 * ntb->db_count;
> > +	void *mw_addr;
> > +	size_t size;
> > +	u32 align;
> > +	int ret;
> > +
> > +	size = sizeof(u32) * ntb->db_count;
> > 
> >  	epc_features = pci_epc_get_features(ntb->epf->epc,
> >  					    ntb->epf->func_no,
> > @@ -557,14 +569,14 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
> >  	return ret;
> > 
> >  err_alloc_peer_mem:
> > -	pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr,
> > mw_addr, epf_bar->size);
> > +	pci_epf_free_space(ntb->epf, mw_addr, barno, 0);
> >  	return -1;
> >  }
> > 
> >  /**
> >   * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
> >   *   allocated in peer's outbound address space
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   */
> >  static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
> >  {
> > @@ -580,8 +592,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
> > 
> >  /**
> >   * epf_ntb_mw_bar_init() - Configure Memory window BARs
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
> >  {
> > @@ -629,7 +642,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
> > 
> >  /**
> >   * epf_ntb_mw_bar_clear() - Clear Memory window BARs
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   */
> >  static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
> >  {
> > @@ -652,7 +665,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb
> > *ntb)
> > 
> >  /**
> >   * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   *
> >   * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB
> > interfaces
> >   */
> > @@ -665,7 +678,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
> >  /**
> >   * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
> >   * constructs (scratchpad region, doorbell, memorywindow)
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
> >  {
> > @@ -706,11 +721,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
> > 
> >  /**
> >   * epf_ntb_epc_init() - Initialize NTB interface
> > - * @ntb: NTB device that facilitates communication between HOST and
> > vHOST2
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   *
> >   * Wrapper to initialize a particular EPC interface and start the workqueue
> > - * to check for commands from host. This function will write to the
> > + * to check for commands from HOST. This function will write to the
> >   * EP controller HW for configuring it.
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_epc_init(struct epf_ntb *ntb)
> >  {
> > @@ -777,7 +794,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
> > 
> >  /**
> >   * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
> > - * @ntb: NTB device that facilitates communication between HOST1 and
> > HOST2
> > + * @ntb: NTB device that facilitates communication between HOST and
> > VHOST
> >   *
> >   * Wrapper to cleanup all NTB interfaces.
> >   */
> > @@ -934,6 +951,8 @@ static const struct config_item_type ntb_group_type
> > = {
> >   *
> >   * Add configfs directory specific to NTB. This directory will hold
> >   * NTB specific properties like db_count, spad_count, num_mws etc.,
> > + *
> > + * Returns: Pointer to config_group
> >   */
> >  static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
> >  					    struct config_group *group)
> > @@ -1084,11 +1103,11 @@ static int vntb_epf_link_enable(struct ntb_dev
> > *ntb,
> >  static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
> >  {
> >  	struct epf_ntb *ntb = ntb_ndev(ndev);
> > -	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4;
> > +	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count *
> > sizeof(u32);
> >  	u32 val;
> > -	void __iomem *base = ntb->reg;
> > +	void __iomem *base = (void __iomem *)ntb->reg;
> > 
> > -	val = readl(base + off + ct + idx * 4);
> > +	val = readl(base + off + ct + idx * sizeof(u32));
> >  	return val;
> >  }
> > 
> > @@ -1096,10 +1115,10 @@ static int vntb_epf_spad_write(struct ntb_dev
> > *ndev, int idx, u32 val)
> >  {
> >  	struct epf_ntb *ntb = ntb_ndev(ndev);
> >  	struct epf_ntb_ctrl *ctrl = ntb->reg;
> > -	int off = ctrl->spad_offset, ct = ctrl->spad_count * 4;
> > -	void __iomem *base = ntb->reg;
> > +	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
> > +	void __iomem *base = (void __iomem *)ntb->reg;
> > 
> > -	writel(val, base + off + ct + idx * 4);
> > +	writel(val, base + off + ct + idx * sizeof(u32));
> >  	return 0;
> >  }
> > 
> > @@ -1108,10 +1127,10 @@ static u32 vntb_epf_peer_spad_read(struct
> > ntb_dev *ndev, int pidx, int idx)
> >  	struct epf_ntb *ntb = ntb_ndev(ndev);
> >  	struct epf_ntb_ctrl *ctrl = ntb->reg;
> >  	int off = ctrl->spad_offset;
> > -	void __iomem *base = ntb->reg;
> > +	void __iomem *base = (void __iomem *)ntb->reg;
> >  	u32 val;
> > 
> > -	val = readl(base + off + idx * 4);
> > +	val = readl(base + off + idx * sizeof(u32));
> >  	return val;
> >  }
> > 
> > @@ -1120,9 +1139,9 @@ static int vntb_epf_peer_spad_write(struct
> > ntb_dev *ndev, int pidx, int idx, u32
> >  	struct epf_ntb *ntb = ntb_ndev(ndev);
> >  	struct epf_ntb_ctrl *ctrl = ntb->reg;
> >  	int off = ctrl->spad_offset;
> > -	void __iomem *base = ntb->reg;
> > +	void __iomem *base = (void __iomem *)ntb->reg;
> > 
> > -	writel(val, base + off + idx * 4);
> > +	writel(val, base + off + idx * sizeof(u32));
> >  	return 0;
> >  }
> > 
> > @@ -1275,6 +1294,8 @@ static struct pci_driver vntb_pci_driver = {
> >   * Invoked when a primary interface or secondary interface is bound to EPC
> >   * device. This function will succeed only when EPC is bound to both the
> >   * interfaces.
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_bind(struct pci_epf *epf)
> >  {
> > @@ -1359,6 +1380,8 @@ static struct pci_epf_ops epf_ntb_ops = {
> >   *
> >   * Probe NTB function driver when endpoint function bus detects a NTB
> >   * endpoint function.
> > + *
> > + * Returns: Zero for success, or an error code in case of failure
> >   */
> >  static int epf_ntb_probe(struct pci_epf *epf)
> >  {
> > --
> > 2.35.1
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

RE: [PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

[Frank Li]

> -----Original Message-----
> From: Frank Li
> Sent: Thursday, September 22, 2022 11:14 AM
> To: maz@kernel.org; tglx@linutronix.de; robh+dt@kernel.org;
> krzysztof.kozlowski+dt@linaro.org; shawnguo@kernel.org;
> s.hauer@pengutronix.de; kw@linux.com; bhelgaas@google.com
> Cc: linux-kernel@vger.kernel.org; devicetree@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; linux-pci@vger.kernel.org; Peng Fan
> <peng.fan@nxp.com>; Aisheng Dong <aisheng.dong@nxp.com>;
> jdmason@kudzu.us; kernel@pengutronix.de; festevam@gmail.com; dl-linux-
> imx <linux-imx@nxp.com>; kishon@ti.com; lorenzo.pieralisi@arm.com;
> ntb@lists.linux.dev; lznuaa@gmail.com; imx@lists.linux.dev;
> manivannan.sadhasivam@linaro.org
> Subject: [PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up
> 

[Frank Li] @Bjorn Helgaas, ping
Patches[1-4] was already picked  by irqchip. 
I think patch[5-6] should go through pci subsystem. 
Any additional comments?


> Remove unused field: epf_db_phy.
> Remove __iomem before epf_db.
> Change epf_db to u32* from void *
> Remove duplicate check if (readl(ntb->epf_db + i * 4)).
> Using sizeof(u32) instead of number 4 at all place.
> 
> Clean up sparse build warning:
>   Using  epf_db[i] instead of readl() because epf_db is located in local
>   memory and allocated by dma_alloc_coherent(). Sparse build warning
> when
>   there are not __iomem at readl().
>   Added __iomem force type convert in vntb_epf_peer_spad_read\write()
> and
>   vntb_epf_spad_read\write(). This require strong order at read and write.
> 
> Replace pci_epc_mem_free_addr() with pci_epf_free_space() at error handle
> path to match pci_epf_alloc_space().
> 
> Cleanup warning found by scripts/kernel-doc
> Fix indentation of the struct epf_ntb_ctrl
> Consolidate term
>   host, host1 to HOST
>   vhost, vHost, Vhost, VHOST2 to VHOST
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/pci/endpoint/functions/pci-epf-vntb.c | 157 ++++++++++--------
>  1 file changed, 90 insertions(+), 67 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 1466dd1904175..acea753af29ed 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -11,7 +11,7 @@
>   * Author: Kishon Vijay Abraham I <kishon@ti.com>
>   */
> 
> -/**
> +/*
>   * +------------+         +---------------------------------------+
>   * |            |         |                                       |
>   * +------------+         |                        +--------------+
> @@ -99,20 +99,20 @@ enum epf_ntb_bar {
>   *       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];
> +	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 {
> @@ -136,8 +136,7 @@ struct epf_ntb {
> 
>  	struct epf_ntb_ctrl *reg;
> 
> -	phys_addr_t epf_db_phy;
> -	void __iomem *epf_db;
> +	u32 *epf_db;
> 
>  	phys_addr_t vpci_mw_phy[MAX_MW];
>  	void __iomem *vpci_mw_addr[MAX_MW];
> @@ -156,12 +155,14 @@ static struct pci_epf_header epf_ntb_header = {
>  };
> 
>  /**
> - * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
> + * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
>   * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @link_up: true or false indicating Link is UP or Down
>   *
>   * Once NTB function in HOST invoke ntb_link_enable(),
> - * this NTB function driver will trigger a link event to vhost.
> + * this NTB function driver will trigger a link event to VHOST.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
>  {
> @@ -175,9 +176,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
>  }
> 
>  /**
> - * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> vhost
> - *   to access the memory window of host
> - * @ntb: NTB device that facilitates communication between host and vhost
> + * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> VHOST
> + *   to access the memory window of HOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @mw: Index of the memory window (either 0, 1, 2 or 3)
>   *
>   *                          EP Outbound Window
> @@ -194,7 +195,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
>   * |        |              |           |
>   * |        |              |           |
>   * +--------+              +-----------+
> - *  VHost                   PCI EP
> + *  VHOST                   PCI EP
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
>  {
> @@ -219,7 +222,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb,
> u32 mw)
> 
>  /**
>   * epf_ntb_teardown_mw() - Teardown the configured OB ATU
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   * @mw: Index of the memory window (either 0, 1, 2 or 3)
>   *
>   * Teardown the configured OB ATU configured in epf_ntb_configure_mw()
> using
> @@ -234,12 +237,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb
> *ntb, u32 mw)
>  }
> 
>  /**
> - * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
> + * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
>   * @work: work_struct for the epf_ntb_epc
>   *
>   * Workqueue function that gets invoked for the two epf_ntb_epc
>   * periodically (once every 5ms) to see if it has received any commands
> - * from NTB host. The host can send commands to configure doorbell or
> + * from NTB HOST. The HOST can send commands to configure doorbell or
>   * configure memory window or to update link status.
>   */
>  static void epf_ntb_cmd_handler(struct work_struct *work)
> @@ -254,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
>  	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
> 
>  	for (i = 1; i < ntb->db_count; i++) {
> -		if (readl(ntb->epf_db + i * 4)) {
> -			if (readl(ntb->epf_db + i * 4))
> -				ntb->db |= 1 << (i - 1);
> -
> +		if (ntb->epf_db[i]) {
>  			ntb_db_event(&ntb->ntb, i);
> -			writel(0, ntb->epf_db + i * 4);
> +			ntb->epf_db[i] = 0;
>  		}
>  	}
> 
> @@ -321,8 +321,8 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
> 
>  /**
>   * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
> - * @ntb_epc: EPC associated with one of the HOST which holds peer's
> outbound
> - *	     address.
> + * @ntb: EPC associated with one of the HOST which holds peer's outbound
> + *	 address.
>   *
>   * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
>   * self scratchpad region (removes inbound ATU configuration). While BAR0
> is
> @@ -331,8 +331,10 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
>   * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
>   *
>   * Please note the self scratchpad region and config region is combined to
> - * a single region and mapped using the same BAR. Also note HOST2's peer
> - * scratchpad is HOST1's self scratchpad.
> + * a single region and mapped using the same BAR. Also note VHOST's peer
> + * scratchpad is HOST's self scratchpad.
> + *
> + * Returns: void
>   */
>  static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -347,13 +349,15 @@ static void epf_ntb_config_sspad_bar_clear(struct
> epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
> - * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
> + * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
>   * self scratchpad region.
>   *
>   * Please note the self scratchpad region and config region is combined to
>   * a single region and mapped using the same BAR.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
>  {
> @@ -380,7 +384,7 @@ static int epf_ntb_config_sspad_bar_set(struct
> epf_ntb *ntb)
>  /**
>   * epf_ntb_config_spad_bar_free() - Free the physical memory associated
> with
>   *   config + scratchpad region
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
>  {
> @@ -393,11 +397,13 @@ static void epf_ntb_config_spad_bar_free(struct
> epf_ntb *ntb)
>  /**
>   * epf_ntb_config_spad_bar_alloc() - Allocate memory for config +
> scratchpad
>   *   region
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Allocate the Local Memory mentioned in the above diagram. The size of
>   * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD
> REGION
>   * is obtained from "spad-count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
>  {
> @@ -424,7 +430,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
>  	spad_count = ntb->spad_count;
> 
>  	ctrl_size = sizeof(struct epf_ntb_ctrl);
> -	spad_size = 2 * spad_count * 4;
> +	spad_size = 2 * spad_count * sizeof(u32);
> 
>  	if (!align) {
>  		ctrl_size = roundup_pow_of_two(ctrl_size);
> @@ -454,7 +460,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
>  	ctrl->num_mws = ntb->num_mws;
>  	ntb->spad_size = spad_size;
> 
> -	ctrl->db_entry_size = 4;
> +	ctrl->db_entry_size = sizeof(u32);
> 
>  	for (i = 0; i < ntb->db_count; i++) {
>  		ntb->reg->db_data[i] = 1 + i;
> @@ -465,11 +471,13 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
>  }
> 
>  /**
> - * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Configure MSI/MSI-X capability for each interface with number of
>   * interrupts equal to "db_count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
>  {
> @@ -511,18 +519,22 @@ static int epf_ntb_configure_interrupt(struct
> epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_db_bar_init() - Configure Doorbell window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
>  {
>  	const struct pci_epc_features *epc_features;
> -	u32 align;
>  	struct device *dev = &ntb->epf->dev;
> -	int ret;
>  	struct pci_epf_bar *epf_bar;
> -	void __iomem *mw_addr;
>  	enum pci_barno barno;
> -	size_t size = 4 * ntb->db_count;
> +	void *mw_addr;
> +	size_t size;
> +	u32 align;
> +	int ret;
> +
> +	size = sizeof(u32) * ntb->db_count;
> 
>  	epc_features = pci_epc_get_features(ntb->epf->epc,
>  					    ntb->epf->func_no,
> @@ -557,14 +569,14 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
>  	return ret;
> 
>  err_alloc_peer_mem:
> -	pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr,
> mw_addr, epf_bar->size);
> +	pci_epf_free_space(ntb->epf, mw_addr, barno, 0);
>  	return -1;
>  }
> 
>  /**
>   * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
>   *   allocated in peer's outbound address space
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -580,8 +592,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_mw_bar_init() - Configure Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
>  {
> @@ -629,7 +642,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_mw_bar_clear() - Clear Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   */
>  static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
>  {
> @@ -652,7 +665,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb
> *ntb)
> 
>  /**
>   * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB
> interfaces
>   */
> @@ -665,7 +678,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
>  /**
>   * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
>   * constructs (scratchpad region, doorbell, memorywindow)
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
>  {
> @@ -706,11 +721,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_epc_init() - Initialize NTB interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper to initialize a particular EPC interface and start the workqueue
> - * to check for commands from host. This function will write to the
> + * to check for commands from HOST. This function will write to the
>   * EP controller HW for configuring it.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_epc_init(struct epf_ntb *ntb)
>  {
> @@ -777,7 +794,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
> 
>  /**
>   * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
>   *
>   * Wrapper to cleanup all NTB interfaces.
>   */
> @@ -934,6 +951,8 @@ static const struct config_item_type ntb_group_type
> = {
>   *
>   * Add configfs directory specific to NTB. This directory will hold
>   * NTB specific properties like db_count, spad_count, num_mws etc.,
> + *
> + * Returns: Pointer to config_group
>   */
>  static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
>  					    struct config_group *group)
> @@ -1084,11 +1103,11 @@ static int vntb_epf_link_enable(struct ntb_dev
> *ntb,
>  static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
>  {
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
> -	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4;
> +	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count *
> sizeof(u32);
>  	u32 val;
> -	void __iomem *base = ntb->reg;
> +	void __iomem *base = (void __iomem *)ntb->reg;
> 
> -	val = readl(base + off + ct + idx * 4);
> +	val = readl(base + off + ct + idx * sizeof(u32));
>  	return val;
>  }
> 
> @@ -1096,10 +1115,10 @@ static int vntb_epf_spad_write(struct ntb_dev
> *ndev, int idx, u32 val)
>  {
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
>  	struct epf_ntb_ctrl *ctrl = ntb->reg;
> -	int off = ctrl->spad_offset, ct = ctrl->spad_count * 4;
> -	void __iomem *base = ntb->reg;
> +	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
> +	void __iomem *base = (void __iomem *)ntb->reg;
> 
> -	writel(val, base + off + ct + idx * 4);
> +	writel(val, base + off + ct + idx * sizeof(u32));
>  	return 0;
>  }
> 
> @@ -1108,10 +1127,10 @@ static u32 vntb_epf_peer_spad_read(struct
> ntb_dev *ndev, int pidx, int idx)
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
>  	struct epf_ntb_ctrl *ctrl = ntb->reg;
>  	int off = ctrl->spad_offset;
> -	void __iomem *base = ntb->reg;
> +	void __iomem *base = (void __iomem *)ntb->reg;
>  	u32 val;
> 
> -	val = readl(base + off + idx * 4);
> +	val = readl(base + off + idx * sizeof(u32));
>  	return val;
>  }
> 
> @@ -1120,9 +1139,9 @@ static int vntb_epf_peer_spad_write(struct
> ntb_dev *ndev, int pidx, int idx, u32
>  	struct epf_ntb *ntb = ntb_ndev(ndev);
>  	struct epf_ntb_ctrl *ctrl = ntb->reg;
>  	int off = ctrl->spad_offset;
> -	void __iomem *base = ntb->reg;
> +	void __iomem *base = (void __iomem *)ntb->reg;
> 
> -	writel(val, base + off + idx * 4);
> +	writel(val, base + off + idx * sizeof(u32));
>  	return 0;
>  }
> 
> @@ -1275,6 +1294,8 @@ static struct pci_driver vntb_pci_driver = {
>   * Invoked when a primary interface or secondary interface is bound to EPC
>   * device. This function will succeed only when EPC is bound to both the
>   * interfaces.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_bind(struct pci_epf *epf)
>  {
> @@ -1359,6 +1380,8 @@ static struct pci_epf_ops epf_ntb_ops = {
>   *
>   * Probe NTB function driver when endpoint function bus detects a NTB
>   * endpoint function.
> + *
> + * Returns: Zero for success, or an error code in case of failure
>   */
>  static int epf_ntb_probe(struct pci_epf *epf)
>  {
> --
> 2.35.1

[PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

[Frank Li]

Remove unused field: epf_db_phy.
Remove __iomem before epf_db.
Change epf_db to u32* from void *
Remove duplicate check if (readl(ntb->epf_db + i * 4)).
Using sizeof(u32) instead of number 4 at all place.

Clean up sparse build warning:
  Using  epf_db[i] instead of readl() because epf_db is located in local
  memory and allocated by dma_alloc_coherent(). Sparse build warning when
  there are not __iomem at readl().
  Added __iomem force type convert in vntb_epf_peer_spad_read\write() and
  vntb_epf_spad_read\write(). This require strong order at read and write.

Replace pci_epc_mem_free_addr() with pci_epf_free_space() at error handle
path to match pci_epf_alloc_space().

Cleanup warning found by scripts/kernel-doc
Fix indentation of the struct epf_ntb_ctrl
Consolidate term
  host, host1 to HOST
  vhost, vHost, Vhost, VHOST2 to VHOST

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 157 ++++++++++--------
 1 file changed, 90 insertions(+), 67 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 1466dd1904175..acea753af29ed 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -11,7 +11,7 @@
  * Author: Kishon Vijay Abraham I <kishon@ti.com>
  */
 
-/**
+/*
  * +------------+         +---------------------------------------+
  * |            |         |                                       |
  * +------------+         |                        +--------------+
@@ -99,20 +99,20 @@ enum epf_ntb_bar {
  *       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];
+	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 {
@@ -136,8 +136,7 @@ struct epf_ntb {
 
 	struct epf_ntb_ctrl *reg;
 
-	phys_addr_t epf_db_phy;
-	void __iomem *epf_db;
+	u32 *epf_db;
 
 	phys_addr_t vpci_mw_phy[MAX_MW];
 	void __iomem *vpci_mw_addr[MAX_MW];
@@ -156,12 +155,14 @@ static struct pci_epf_header epf_ntb_header = {
 };
 
 /**
- * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
+ * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
  * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @link_up: true or false indicating Link is UP or Down
  *
  * Once NTB function in HOST invoke ntb_link_enable(),
- * this NTB function driver will trigger a link event to vhost.
+ * this NTB function driver will trigger a link event to VHOST.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
 {
@@ -175,9 +176,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
 }
 
 /**
- * epf_ntb_configure_mw() - Configure the Outbound Address Space for vhost
- *   to access the memory window of host
- * @ntb: NTB device that facilitates communication between host and vhost
+ * epf_ntb_configure_mw() - Configure the Outbound Address Space for VHOST
+ *   to access the memory window of HOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @mw: Index of the memory window (either 0, 1, 2 or 3)
  *
  *                          EP Outbound Window
@@ -194,7 +195,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
  * |        |              |           |
  * |        |              |           |
  * +--------+              +-----------+
- *  VHost                   PCI EP
+ *  VHOST                   PCI EP
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
 {
@@ -219,7 +222,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
 
 /**
  * epf_ntb_teardown_mw() - Teardown the configured OB ATU
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  * @mw: Index of the memory window (either 0, 1, 2 or 3)
  *
  * Teardown the configured OB ATU configured in epf_ntb_configure_mw() using
@@ -234,12 +237,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb *ntb, u32 mw)
 }
 
 /**
- * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
+ * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
  * @work: work_struct for the epf_ntb_epc
  *
  * Workqueue function that gets invoked for the two epf_ntb_epc
  * periodically (once every 5ms) to see if it has received any commands
- * from NTB host. The host can send commands to configure doorbell or
+ * from NTB HOST. The HOST can send commands to configure doorbell or
  * configure memory window or to update link status.
  */
 static void epf_ntb_cmd_handler(struct work_struct *work)
@@ -254,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
 
 	for (i = 1; i < ntb->db_count; i++) {
-		if (readl(ntb->epf_db + i * 4)) {
-			if (readl(ntb->epf_db + i * 4))
-				ntb->db |= 1 << (i - 1);
-
+		if (ntb->epf_db[i]) {
 			ntb_db_event(&ntb->ntb, i);
-			writel(0, ntb->epf_db + i * 4);
+			ntb->epf_db[i] = 0;
 		}
 	}
 
@@ -321,8 +321,8 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 
 /**
  * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
- * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound
- *	     address.
+ * @ntb: EPC associated with one of the HOST which holds peer's outbound
+ *	 address.
  *
  * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
  * self scratchpad region (removes inbound ATU configuration). While BAR0 is
@@ -331,8 +331,10 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
  * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
  *
  * Please note the self scratchpad region and config region is combined to
- * a single region and mapped using the same BAR. Also note HOST2's peer
- * scratchpad is HOST1's self scratchpad.
+ * a single region and mapped using the same BAR. Also note VHOST's peer
+ * scratchpad is HOST's self scratchpad.
+ *
+ * Returns: void
  */
 static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
 {
@@ -347,13 +349,15 @@ static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
- * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
+ * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
  * self scratchpad region.
  *
  * Please note the self scratchpad region and config region is combined to
  * a single region and mapped using the same BAR.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
 {
@@ -380,7 +384,7 @@ static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
 /**
  * epf_ntb_config_spad_bar_free() - Free the physical memory associated with
  *   config + scratchpad region
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
 {
@@ -393,11 +397,13 @@ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
 /**
  * epf_ntb_config_spad_bar_alloc() - Allocate memory for config + scratchpad
  *   region
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Allocate the Local Memory mentioned in the above diagram. The size of
  * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD REGION
  * is obtained from "spad-count" configfs entry.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 {
@@ -424,7 +430,7 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 	spad_count = ntb->spad_count;
 
 	ctrl_size = sizeof(struct epf_ntb_ctrl);
-	spad_size = 2 * spad_count * 4;
+	spad_size = 2 * spad_count * sizeof(u32);
 
 	if (!align) {
 		ctrl_size = roundup_pow_of_two(ctrl_size);
@@ -454,7 +460,7 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 	ctrl->num_mws = ntb->num_mws;
 	ntb->spad_size = spad_size;
 
-	ctrl->db_entry_size = 4;
+	ctrl->db_entry_size = sizeof(u32);
 
 	for (i = 0; i < ntb->db_count; i++) {
 		ntb->reg->db_data[i] = 1 + i;
@@ -465,11 +471,13 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 }
 
 /**
- * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Configure MSI/MSI-X capability for each interface with number of
  * interrupts equal to "db_count" configfs entry.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 {
@@ -511,18 +519,22 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_db_bar_init() - Configure Doorbell window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 {
 	const struct pci_epc_features *epc_features;
-	u32 align;
 	struct device *dev = &ntb->epf->dev;
-	int ret;
 	struct pci_epf_bar *epf_bar;
-	void __iomem *mw_addr;
 	enum pci_barno barno;
-	size_t size = 4 * ntb->db_count;
+	void *mw_addr;
+	size_t size;
+	u32 align;
+	int ret;
+
+	size = sizeof(u32) * ntb->db_count;
 
 	epc_features = pci_epc_get_features(ntb->epf->epc,
 					    ntb->epf->func_no,
@@ -557,14 +569,14 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 	return ret;
 
 err_alloc_peer_mem:
-	pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr, mw_addr, epf_bar->size);
+	pci_epf_free_space(ntb->epf, mw_addr, barno, 0);
 	return -1;
 }
 
 /**
  * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
  *   allocated in peer's outbound address space
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
 {
@@ -580,8 +592,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_mw_bar_init() - Configure Memory window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
 {
@@ -629,7 +642,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_mw_bar_clear() - Clear Memory window BARs
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  */
 static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
 {
@@ -652,7 +665,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces
  */
@@ -665,7 +678,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
 /**
  * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
  * constructs (scratchpad region, doorbell, memorywindow)
- * @ntb: NTB device that facilitates communication between HOST and vHOST
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
 {
@@ -706,11 +721,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_init() - Initialize NTB interface
- * @ntb: NTB device that facilitates communication between HOST and vHOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper to initialize a particular EPC interface and start the workqueue
- * to check for commands from host. This function will write to the
+ * to check for commands from HOST. This function will write to the
  * EP controller HW for configuring it.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_epc_init(struct epf_ntb *ntb)
 {
@@ -777,7 +794,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
 
 /**
  * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
  *
  * Wrapper to cleanup all NTB interfaces.
  */
@@ -934,6 +951,8 @@ static const struct config_item_type ntb_group_type = {
  *
  * Add configfs directory specific to NTB. This directory will hold
  * NTB specific properties like db_count, spad_count, num_mws etc.,
+ *
+ * Returns: Pointer to config_group
  */
 static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
 					    struct config_group *group)
@@ -1084,11 +1103,11 @@ static int vntb_epf_link_enable(struct ntb_dev *ntb,
 static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
-	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4;
+	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
 	u32 val;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
-	val = readl(base + off + ct + idx * 4);
+	val = readl(base + off + ct + idx * sizeof(u32));
 	return val;
 }
 
@@ -1096,10 +1115,10 @@ static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
-	int off = ctrl->spad_offset, ct = ctrl->spad_count * 4;
-	void __iomem *base = ntb->reg;
+	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
+	void __iomem *base = (void __iomem *)ntb->reg;
 
-	writel(val, base + off + ct + idx * 4);
+	writel(val, base + off + ct + idx * sizeof(u32));
 	return 0;
 }
 
@@ -1108,10 +1127,10 @@ static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 	u32 val;
 
-	val = readl(base + off + idx * 4);
+	val = readl(base + off + idx * sizeof(u32));
 	return val;
 }
 
@@ -1120,9 +1139,9 @@ static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
-	writel(val, base + off + idx * 4);
+	writel(val, base + off + idx * sizeof(u32));
 	return 0;
 }
 
@@ -1275,6 +1294,8 @@ static struct pci_driver vntb_pci_driver = {
  * Invoked when a primary interface or secondary interface is bound to EPC
  * device. This function will succeed only when EPC is bound to both the
  * interfaces.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_bind(struct pci_epf *epf)
 {
@@ -1359,6 +1380,8 @@ static struct pci_epf_ops epf_ntb_ops = {
  *
  * Probe NTB function driver when endpoint function bus detects a NTB
  * endpoint function.
+ *
+ * Returns: Zero for success, or an error code in case of failure
  */
 static int epf_ntb_probe(struct pci_epf *epf)
 {
-- 
2.35.1