net: Add SIOCGI2CPB ioctl & add page/bank fields to ifi2creq

This commit adds page & bank fields to ifi2creq in preparation
for adding CMIS support for 400g optics to ifconfig.
The new ioctl SIOCGI2CPB is added, so that drivers can distinguish
between callers asking for page/bank selection and legacy callers
that simply failed to zero out all ifi2creq fields.

The mlx5en(4) driver and iflib(4) driver frameork have been updated
to use this new SIOCGI2CPB ioctl and support page/bank operations.
A follow-on patchset will add support to ifconfig for reporting
data from CMIS optics.

This has been tested on Nvidia ConnectX-7 and Broadcom Thor2 (using
out of tree driver) based NICs.

Differential Revision: https://reviews.freebsd.org/D55912
Sponsored by: Netflix Inc.
Reviewed by: kib

sys/dev/mlx5/mlx5_en/mlx5_en_main.c

@@ -3728,6 +3728,8 @@ mlx5e_ioctl(if_t ifp, u_long command, caddr_t data)
 		break;
 
 	case SIOCGI2C:
+		/* fallthru */
+	case SIOCGI2CPB:
 		ifr = (struct ifreq *)data;
 
 		/*
@@ -3737,6 +3739,9 @@ mlx5e_ioctl(if_t ifp, u_long command, caddr_t data)
 		error = copyin(ifr_data_get_ptr(ifr), &i2c, sizeof(i2c));
 		if (error)
 			break;
+		/* ensure page and bank are 0 for legacy SIOCGI2C ioctls */
+		if (command == SIOCGI2C)
+			i2c.page = i2c.bank = 0;
 
 		if (i2c.len > sizeof(i2c.data)) {
 			error = EINVAL;
@@ -3778,8 +3783,17 @@ mlx5e_ioctl(if_t ifp, u_long command, caddr_t data)
 			error = EINVAL;
 			goto err_i2c;
 		}
+
+		if (i2c.bank != 0) {
+			mlx5_en_err(ifp,
+			    "Query eeprom failed, Invalid Bank: %X\n",
+			    i2c.bank);
+			error = EINVAL;
+			goto err_i2c;
+		}
+
 		error = mlx5_query_eeprom(priv->mdev,
-		    read_addr, MLX5_EEPROM_LOW_PAGE,
+		    read_addr, i2c.page,
 		    (uint32_t)i2c.offset, (uint32_t)i2c.len, module_num,
 		    (uint32_t *)i2c.data, &size_read);
 		if (error) {
@@ -3791,7 +3805,7 @@ mlx5e_ioctl(if_t ifp, u_long command, caddr_t data)
 
 		if (i2c.len > MLX5_EEPROM_MAX_BYTES) {
 			error = mlx5_query_eeprom(priv->mdev,
-			    read_addr, MLX5_EEPROM_LOW_PAGE,
+			    read_addr, i2c.page,
 			    (uint32_t)(i2c.offset + size_read),
 			    (uint32_t)(i2c.len - size_read), module_num,
 			    (uint32_t *)(i2c.data + size_read), &size_read);

sys/net/if.h

@@ -604,8 +604,9 @@ struct ifi2creq {
 	uint8_t dev_addr;	/* i2c address (0xA0, 0xA2) */
 	uint8_t offset;		/* read offset */
 	uint8_t len;		/* read length */
-	uint8_t spare0;
-	uint32_t spare1;
+	uint8_t page;		/* CMIS page number (0 for legacy) */
+	uint8_t bank;		/* CMIS bank number (0 for legacy) */
+	uint8_t spare[3];	/* reserved for future use */
 	uint8_t data[8];	/* read buffer */
 }; 
 

sys/net/iflib.c

@@ -4468,8 +4468,11 @@ iflib_if_ioctl(if_t ifp, u_long command, caddr_t data)
 		err = ifmedia_ioctl(ifp, ifr, ctx->ifc_mediap, command);
 		break;
 	case SIOCGI2C:
+		/* FALLTHROUGH */
+	case SIOCGI2CPB:
 	{
 		struct ifi2creq i2c;
+		if_shared_ctx_t sctx = ctx->ifc_sctx;
 
 		err = copyin(ifr_data_get_ptr(ifr), &i2c, sizeof(i2c));
 		if (err != 0)
@@ -4482,6 +4485,12 @@ iflib_if_ioctl(if_t ifp, u_long command, caddr_t data)
 			err = EINVAL;
 			break;
 		}
+		if (command == SIOCGI2C) {
+			i2c.page = i2c.bank = 0;
+		} else if ((sctx->isc_flags & IFLIB_I2C_PAGE_BANK) == 0) {
+			err = EINVAL;
+			break;
+		}
 
 		if ((err = IFDI_I2C_REQ(ctx, &i2c)) == 0)
 			err = copyout(&i2c, ifr_data_get_ptr(ifr),

sys/net/iflib.h

@@ -348,7 +348,10 @@ typedef enum {
  * Driver needs frames padded to some minimum length
  */
 #define IFLIB_NEED_ETHER_PAD	0x100
-#define	IFLIB_SPARE7		0x200
+/*
+ * Driver understands page/bank i2c reads
+ */
+#define	IFLIB_I2C_PAGE_BANK	0x200
 #define	IFLIB_SPARE6		0x400
 #define	IFLIB_SPARE5		0x800
 #define	IFLIB_SPARE4		0x1000

sys/sys/sockio.h

@@ -150,5 +150,6 @@
 #define	SIOCGUMBINFO	_IOWR('i', 157, struct ifreq)	/* get MBIM info */
 #define	SIOCSUMBPARAM	 _IOW('i', 158, struct ifreq)	/* set MBIM param */
 #define	SIOCGUMBPARAM	_IOWR('i', 159, struct ifreq)	/* get MBIM param */
+#define	SIOCGI2CPB	_IOWR('i', 160, struct ifreq)	/* get I2C data   */
 
 #endif /* !_SYS_SOCKIO_H_ */