sfc: Extend MTD driver for use with new NICs

In new NICs flash is managed by firmware and we will use high-level
operations on partitions rather than direct SPI commands.  Add support
for multiple MTD partitions per flash device and remove the direct
link between MTD and SPI devices.  Maintain a list of MTD partitions
in struct efx_nic.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sfc/mtd.c b/drivers/net/sfc/mtd.c
index 820c233..3121e24 100644
--- a/drivers/net/sfc/mtd.c
+++ b/drivers/net/sfc/mtd.c
@@ -11,26 +11,58 @@
 #include <linux/module.h>
 #include <linux/mtd/mtd.h>
 #include <linux/delay.h>
+#include <linux/rtnetlink.h>
 
 #define EFX_DRIVER_NAME "sfc_mtd"
 #include "net_driver.h"
 #include "spi.h"
 #include "efx.h"
+#include "falcon.h"
 
 #define EFX_SPI_VERIFY_BUF_LEN 16
 
-struct efx_mtd {
-	const struct efx_spi_device *spi;
+struct efx_mtd_partition {
 	struct mtd_info mtd;
+	size_t offset;
+	const char *type_name;
 	char name[IFNAMSIZ + 20];
 };
 
+struct efx_mtd_ops {
+	int (*read)(struct mtd_info *mtd, loff_t start, size_t len,
+		    size_t *retlen, u8 *buffer);
+	int (*erase)(struct mtd_info *mtd, loff_t start, size_t len);
+	int (*write)(struct mtd_info *mtd, loff_t start, size_t len,
+		     size_t *retlen, const u8 *buffer);
+	int (*sync)(struct mtd_info *mtd);
+};
+
+struct efx_mtd {
+	struct list_head node;
+	struct efx_nic *efx;
+	const struct efx_spi_device *spi;
+	const char *name;
+	const struct efx_mtd_ops *ops;
+	size_t n_parts;
+	struct efx_mtd_partition part[0];
+};
+
+#define efx_for_each_partition(part, efx_mtd)			\
+	for ((part) = &(efx_mtd)->part[0];			\
+	     (part) != &(efx_mtd)->part[(efx_mtd)->n_parts];	\
+	     (part)++)
+
+#define to_efx_mtd_partition(mtd)				\
+	container_of(mtd, struct efx_mtd_partition, mtd)
+
+static int falcon_mtd_probe(struct efx_nic *efx);
+
 /* SPI utilities */
 
 static int efx_spi_slow_wait(struct efx_mtd *efx_mtd, bool uninterruptible)
 {
 	const struct efx_spi_device *spi = efx_mtd->spi;
-	struct efx_nic *efx = spi->efx;
+	struct efx_nic *efx = efx_mtd->efx;
 	u8 status;
 	int rc, i;
 
@@ -39,7 +71,7 @@
 		__set_current_state(uninterruptible ?
 				    TASK_UNINTERRUPTIBLE : TASK_INTERRUPTIBLE);
 		schedule_timeout(HZ / 10);
-		rc = falcon_spi_cmd(spi, SPI_RDSR, -1, NULL,
+		rc = falcon_spi_cmd(efx, spi, SPI_RDSR, -1, NULL,
 				    &status, sizeof(status));
 		if (rc)
 			return rc;
@@ -52,32 +84,35 @@
 	return -ETIMEDOUT;
 }
 
-static int efx_spi_unlock(const struct efx_spi_device *spi)
+static int
+efx_spi_unlock(struct efx_nic *efx, const struct efx_spi_device *spi)
 {
 	const u8 unlock_mask = (SPI_STATUS_BP2 | SPI_STATUS_BP1 |
 				SPI_STATUS_BP0);
 	u8 status;
 	int rc;
 
-	rc = falcon_spi_cmd(spi, SPI_RDSR, -1, NULL, &status, sizeof(status));
+	rc = falcon_spi_cmd(efx, spi, SPI_RDSR, -1, NULL,
+			    &status, sizeof(status));
 	if (rc)
 		return rc;
 
 	if (!(status & unlock_mask))
 		return 0; /* already unlocked */
 
-	rc = falcon_spi_cmd(spi, SPI_WREN, -1, NULL, NULL, 0);
+	rc = falcon_spi_cmd(efx, spi, SPI_WREN, -1, NULL, NULL, 0);
 	if (rc)
 		return rc;
-	rc = falcon_spi_cmd(spi, SPI_SST_EWSR, -1, NULL, NULL, 0);
+	rc = falcon_spi_cmd(efx, spi, SPI_SST_EWSR, -1, NULL, NULL, 0);
 	if (rc)
 		return rc;
 
 	status &= ~unlock_mask;
-	rc = falcon_spi_cmd(spi, SPI_WRSR, -1, &status, NULL, sizeof(status));
+	rc = falcon_spi_cmd(efx, spi, SPI_WRSR, -1, &status,
+			    NULL, sizeof(status));
 	if (rc)
 		return rc;
-	rc = falcon_spi_wait_write(spi);
+	rc = falcon_spi_wait_write(efx, spi);
 	if (rc)
 		return rc;
 
@@ -87,6 +122,7 @@
 static int efx_spi_erase(struct efx_mtd *efx_mtd, loff_t start, size_t len)
 {
 	const struct efx_spi_device *spi = efx_mtd->spi;
+	struct efx_nic *efx = efx_mtd->efx;
 	unsigned pos, block_len;
 	u8 empty[EFX_SPI_VERIFY_BUF_LEN];
 	u8 buffer[EFX_SPI_VERIFY_BUF_LEN];
@@ -98,13 +134,14 @@
 	if (spi->erase_command == 0)
 		return -EOPNOTSUPP;
 
-	rc = efx_spi_unlock(spi);
+	rc = efx_spi_unlock(efx, spi);
 	if (rc)
 		return rc;
-	rc = falcon_spi_cmd(spi, SPI_WREN, -1, NULL, NULL, 0);
+	rc = falcon_spi_cmd(efx, spi, SPI_WREN, -1, NULL, NULL, 0);
 	if (rc)
 		return rc;
-	rc = falcon_spi_cmd(spi, spi->erase_command, start, NULL, NULL, 0);
+	rc = falcon_spi_cmd(efx, spi, spi->erase_command, start, NULL,
+			    NULL, 0);
 	if (rc)
 		return rc;
 	rc = efx_spi_slow_wait(efx_mtd, false);
@@ -113,7 +150,8 @@
 	memset(empty, 0xff, sizeof(empty));
 	for (pos = 0; pos < len; pos += block_len) {
 		block_len = min(len - pos, sizeof(buffer));
-		rc = falcon_spi_read(spi, start + pos, block_len, NULL, buffer);
+		rc = falcon_spi_read(efx, spi, start + pos, block_len,
+				     NULL, buffer);
 		if (rc)
 			return rc;
 		if (memcmp(empty, buffer, block_len))
@@ -130,36 +168,12 @@
 
 /* MTD interface */
 
-static int efx_mtd_read(struct mtd_info *mtd, loff_t start, size_t len,
-			size_t *retlen, u8 *buffer)
-{
-	struct efx_mtd *efx_mtd = mtd->priv;
-	const struct efx_spi_device *spi = efx_mtd->spi;
-	struct efx_nic *efx = spi->efx;
-	int rc;
-
-	rc = mutex_lock_interruptible(&efx->spi_lock);
-	if (rc)
-		return rc;
-	rc = falcon_spi_read(spi, FALCON_FLASH_BOOTCODE_START + start,
-			     len, retlen, buffer);
-	mutex_unlock(&efx->spi_lock);
-	return rc;
-}
-
 static int efx_mtd_erase(struct mtd_info *mtd, struct erase_info *erase)
 {
 	struct efx_mtd *efx_mtd = mtd->priv;
-	struct efx_nic *efx = efx_mtd->spi->efx;
 	int rc;
 
-	rc = mutex_lock_interruptible(&efx->spi_lock);
-	if (rc)
-		return rc;
-	rc = efx_spi_erase(efx_mtd, FALCON_FLASH_BOOTCODE_START + erase->addr,
-			   erase->len);
-	mutex_unlock(&efx->spi_lock);
-
+	rc = efx_mtd->ops->erase(mtd, erase->addr, erase->len);
 	if (rc == 0) {
 		erase->state = MTD_ERASE_DONE;
 	} else {
@@ -170,100 +184,212 @@
 	return rc;
 }
 
-static int efx_mtd_write(struct mtd_info *mtd, loff_t start,
-			 size_t len, size_t *retlen, const u8 *buffer)
+static void efx_mtd_sync(struct mtd_info *mtd)
 {
 	struct efx_mtd *efx_mtd = mtd->priv;
+	struct efx_nic *efx = efx_mtd->efx;
+	int rc;
+
+	rc = efx_mtd->ops->sync(mtd);
+	if (rc)
+		EFX_ERR(efx, "%s sync failed (%d)\n", efx_mtd->name, rc);
+}
+
+static void efx_mtd_remove_partition(struct efx_mtd_partition *part)
+{
+	int rc;
+
+	for (;;) {
+		rc = del_mtd_device(&part->mtd);
+		if (rc != -EBUSY)
+			break;
+		ssleep(1);
+	}
+	WARN_ON(rc);
+}
+
+static void efx_mtd_remove_device(struct efx_mtd *efx_mtd)
+{
+	struct efx_mtd_partition *part;
+
+	efx_for_each_partition(part, efx_mtd)
+		efx_mtd_remove_partition(part);
+	list_del(&efx_mtd->node);
+	kfree(efx_mtd);
+}
+
+static void efx_mtd_rename_device(struct efx_mtd *efx_mtd)
+{
+	struct efx_mtd_partition *part;
+
+	efx_for_each_partition(part, efx_mtd)
+		snprintf(part->name, sizeof(part->name),
+			 "%s %s", efx_mtd->efx->name,
+			 part->type_name);
+}
+
+static int efx_mtd_probe_device(struct efx_nic *efx, struct efx_mtd *efx_mtd)
+{
+	struct efx_mtd_partition *part;
+
+	efx_mtd->efx = efx;
+
+	efx_mtd_rename_device(efx_mtd);
+
+	efx_for_each_partition(part, efx_mtd) {
+		part->mtd.writesize = 1;
+
+		part->mtd.owner = THIS_MODULE;
+		part->mtd.priv = efx_mtd;
+		part->mtd.name = part->name;
+		part->mtd.erase = efx_mtd_erase;
+		part->mtd.read = efx_mtd->ops->read;
+		part->mtd.write = efx_mtd->ops->write;
+		part->mtd.sync = efx_mtd_sync;
+
+		if (add_mtd_device(&part->mtd))
+			goto fail;
+	}
+
+	list_add(&efx_mtd->node, &efx->mtd_list);
+	return 0;
+
+fail:
+	while (part != &efx_mtd->part[0]) {
+		--part;
+		efx_mtd_remove_partition(part);
+	}
+	/* add_mtd_device() returns 1 if the MTD table is full */
+	return -ENOMEM;
+}
+
+void efx_mtd_remove(struct efx_nic *efx)
+{
+	struct efx_mtd *efx_mtd, *next;
+
+	WARN_ON(efx_dev_registered(efx));
+
+	list_for_each_entry_safe(efx_mtd, next, &efx->mtd_list, node)
+		efx_mtd_remove_device(efx_mtd);
+}
+
+void efx_mtd_rename(struct efx_nic *efx)
+{
+	struct efx_mtd *efx_mtd;
+
+	ASSERT_RTNL();
+
+	list_for_each_entry(efx_mtd, &efx->mtd_list, node)
+		efx_mtd_rename_device(efx_mtd);
+}
+
+int efx_mtd_probe(struct efx_nic *efx)
+{
+	return falcon_mtd_probe(efx);
+}
+
+/* Implementation of MTD operations for Falcon */
+
+static int falcon_mtd_read(struct mtd_info *mtd, loff_t start,
+			   size_t len, size_t *retlen, u8 *buffer)
+{
+	struct efx_mtd_partition *part = to_efx_mtd_partition(mtd);
+	struct efx_mtd *efx_mtd = mtd->priv;
 	const struct efx_spi_device *spi = efx_mtd->spi;
-	struct efx_nic *efx = spi->efx;
+	struct efx_nic *efx = efx_mtd->efx;
 	int rc;
 
 	rc = mutex_lock_interruptible(&efx->spi_lock);
 	if (rc)
 		return rc;
-	rc = falcon_spi_write(spi, FALCON_FLASH_BOOTCODE_START + start,
-			      len, retlen, buffer);
+	rc = falcon_spi_read(efx, spi, part->offset + start, len,
+			     retlen, buffer);
 	mutex_unlock(&efx->spi_lock);
 	return rc;
 }
 
-static void efx_mtd_sync(struct mtd_info *mtd)
+static int falcon_mtd_erase(struct mtd_info *mtd, loff_t start, size_t len)
+{
+	struct efx_mtd_partition *part = to_efx_mtd_partition(mtd);
+	struct efx_mtd *efx_mtd = mtd->priv;
+	struct efx_nic *efx = efx_mtd->efx;
+	int rc;
+
+	rc = mutex_lock_interruptible(&efx->spi_lock);
+	if (rc)
+		return rc;
+	rc = efx_spi_erase(efx_mtd, part->offset + start, len);
+	mutex_unlock(&efx->spi_lock);
+	return rc;
+}
+
+static int falcon_mtd_write(struct mtd_info *mtd, loff_t start,
+			    size_t len, size_t *retlen, const u8 *buffer)
+{
+	struct efx_mtd_partition *part = to_efx_mtd_partition(mtd);
+	struct efx_mtd *efx_mtd = mtd->priv;
+	const struct efx_spi_device *spi = efx_mtd->spi;
+	struct efx_nic *efx = efx_mtd->efx;
+	int rc;
+
+	rc = mutex_lock_interruptible(&efx->spi_lock);
+	if (rc)
+		return rc;
+	rc = falcon_spi_write(efx, spi, part->offset + start, len,
+			      retlen, buffer);
+	mutex_unlock(&efx->spi_lock);
+	return rc;
+}
+
+static int falcon_mtd_sync(struct mtd_info *mtd)
 {
 	struct efx_mtd *efx_mtd = mtd->priv;
-	struct efx_nic *efx = efx_mtd->spi->efx;
+	struct efx_nic *efx = efx_mtd->efx;
 	int rc;
 
 	mutex_lock(&efx->spi_lock);
 	rc = efx_spi_slow_wait(efx_mtd, true);
 	mutex_unlock(&efx->spi_lock);
-
-	if (rc)
-		EFX_ERR(efx, "%s sync failed (%d)\n", efx_mtd->name, rc);
-	return;
+	return rc;
 }
 
-void efx_mtd_remove(struct efx_nic *efx)
-{
-	if (efx->spi_flash && efx->spi_flash->mtd) {
-		struct efx_mtd *efx_mtd = efx->spi_flash->mtd;
-		int rc;
+static struct efx_mtd_ops falcon_mtd_ops = {
+	.read	= falcon_mtd_read,
+	.erase	= falcon_mtd_erase,
+	.write	= falcon_mtd_write,
+	.sync	= falcon_mtd_sync,
+};
 
-		for (;;) {
-			rc = del_mtd_device(&efx_mtd->mtd);
-			if (rc != -EBUSY)
-				break;
-			ssleep(1);
-		}
-		WARN_ON(rc);
-		kfree(efx_mtd);
-	}
-}
-
-void efx_mtd_rename(struct efx_nic *efx)
-{
-	if (efx->spi_flash && efx->spi_flash->mtd) {
-		struct efx_mtd *efx_mtd = efx->spi_flash->mtd;
-		snprintf(efx_mtd->name, sizeof(efx_mtd->name),
-			 "%s sfc_flash_bootrom", efx->name);
-	}
-}
-
-int efx_mtd_probe(struct efx_nic *efx)
+static int falcon_mtd_probe(struct efx_nic *efx)
 {
 	struct efx_spi_device *spi = efx->spi_flash;
 	struct efx_mtd *efx_mtd;
+	int rc;
+
+	ASSERT_RTNL();
 
 	if (!spi || spi->size <= FALCON_FLASH_BOOTCODE_START)
 		return -ENODEV;
 
-	efx_mtd = kzalloc(sizeof(*efx_mtd), GFP_KERNEL);
+	efx_mtd = kzalloc(sizeof(*efx_mtd) + sizeof(efx_mtd->part[0]),
+			  GFP_KERNEL);
 	if (!efx_mtd)
 		return -ENOMEM;
 
 	efx_mtd->spi = spi;
-	spi->mtd = efx_mtd;
+	efx_mtd->name = "flash";
+	efx_mtd->ops = &falcon_mtd_ops;
 
-	efx_mtd->mtd.type = MTD_NORFLASH;
-	efx_mtd->mtd.flags = MTD_CAP_NORFLASH;
-	efx_mtd->mtd.size = spi->size - FALCON_FLASH_BOOTCODE_START;
-	efx_mtd->mtd.erasesize = spi->erase_size;
-	efx_mtd->mtd.writesize = 1;
-	efx_mtd_rename(efx);
+	efx_mtd->n_parts = 1;
+	efx_mtd->part[0].mtd.type = MTD_NORFLASH;
+	efx_mtd->part[0].mtd.flags = MTD_CAP_NORFLASH;
+	efx_mtd->part[0].mtd.size = spi->size - FALCON_FLASH_BOOTCODE_START;
+	efx_mtd->part[0].mtd.erasesize = spi->erase_size;
+	efx_mtd->part[0].offset = FALCON_FLASH_BOOTCODE_START;
+	efx_mtd->part[0].type_name = "sfc_flash_bootrom";
 
-	efx_mtd->mtd.owner = THIS_MODULE;
-	efx_mtd->mtd.priv = efx_mtd;
-	efx_mtd->mtd.name = efx_mtd->name;
-	efx_mtd->mtd.erase = efx_mtd_erase;
-	efx_mtd->mtd.read = efx_mtd_read;
-	efx_mtd->mtd.write = efx_mtd_write;
-	efx_mtd->mtd.sync = efx_mtd_sync;
-
-	if (add_mtd_device(&efx_mtd->mtd)) {
+	rc = efx_mtd_probe_device(efx, efx_mtd);
+	if (rc)
 		kfree(efx_mtd);
-		spi->mtd = NULL;
-		/* add_mtd_device() returns 1 if the MTD table is full */
-		return -ENOMEM;
-	}
-
-	return 0;
+	return rc;
 }