net: stmmac: mostly remove "buf_sz"

The "buf_sz" parameter is not used in the stmmac driver - there is one
place where the value of buf_sz is validated, and two places where it
is written. It is otherwise unused.

Remove these accesses. However, leave the module parameter in place as
removing it could cause module load to fail, breaking user setups.

Signed-off-by: Russell King (Oracle) <[email protected]>
Reviewed-by: Furong Xu <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Russell King (Oracle)

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -101,6 +101,7 @@ static int tc = TC_DEFAULT;
 module_param(tc, int, 0644);
 MODULE_PARM_DESC(tc, "DMA threshold control value");
 
+/* This is unused */
 #define	DEFAULT_BUFSIZE	1536
 static int buf_sz = DEFAULT_BUFSIZE;
 module_param(buf_sz, int, 0644);
@@ -218,8 +219,6 @@ static void stmmac_verify_args(void)
 {
 	if (unlikely(watchdog < 0))
 		watchdog = TX_TIMEO;
-	if (unlikely((buf_sz < DEFAULT_BUFSIZE) || (buf_sz > BUF_SIZE_16KiB)))
-		buf_sz = DEFAULT_BUFSIZE;
 	if (unlikely((pause < 0) || (pause > 0xffff)))
 		pause = PAUSE_TIME;
 
@@ -4028,7 +4027,6 @@ static int __stmmac_open(struct net_device *dev,
 		}
 	}
 
-	buf_sz = dma_conf->dma_buf_sz;
 	for (int i = 0; i < MTL_MAX_TX_QUEUES; i++)
 		if (priv->dma_conf.tx_queue[i].tbs & STMMAC_TBS_EN)
 			dma_conf->tx_queue[i].tbs = priv->dma_conf.tx_queue[i].tbs;
@@ -7989,9 +7987,6 @@ static int __init stmmac_cmdline_opt(char *str)
 		} else if (!strncmp(opt, "phyaddr:", 8)) {
 			if (kstrtoint(opt + 8, 0, &phyaddr))
 				goto err;
-		} else if (!strncmp(opt, "buf_sz:", 7)) {
-			if (kstrtoint(opt + 7, 0, &buf_sz))
-				goto err;
 		} else if (!strncmp(opt, "tc:", 3)) {
 			if (kstrtoint(opt + 3, 0, &tc))
 				goto err;