net: mvpp2: Improve data types and use min()

Change the data type of the variable freq in mvpp2_rx_time_coal_set()
and mvpp2_tx_time_coal_set() to u32 because port->priv->tclk also has
the data type u32.

Change the data type of the function parameter clk_hz in
mvpp2_usec_to_cycles() and mvpp2_cycles_to_usec() to u32 accordingly
and remove the following Coccinelle/coccicheck warning reported by
do_div.cocci:

  WARNING: do_div() does a 64-by-32 division, please consider using div64_ul instead

Use min() to simplify the code and improve its readability.

Compile-tested only.
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240711154741.174745-1-thorsten.blum@toblux.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c

@@ -2766,29 +2766,29 @@ static void mvpp2_tx_pkts_coal_set(struct mvpp2_port *port,
 	}
 }
 
-static u32 mvpp2_usec_to_cycles(u32 usec, unsigned long clk_hz)
+static u32 mvpp2_usec_to_cycles(u32 usec, u32 clk_hz)
 {
 	u64 tmp = (u64)clk_hz * usec;
 
 	do_div(tmp, USEC_PER_SEC);
 
-	return tmp > U32_MAX ? U32_MAX : tmp;
+	return min(tmp, U32_MAX);
 }
 
-static u32 mvpp2_cycles_to_usec(u32 cycles, unsigned long clk_hz)
+static u32 mvpp2_cycles_to_usec(u32 cycles, u32 clk_hz)
 {
 	u64 tmp = (u64)cycles * USEC_PER_SEC;
 
 	do_div(tmp, clk_hz);
 
-	return tmp > U32_MAX ? U32_MAX : tmp;
+	return min(tmp, U32_MAX);
 }
 
 /* Set the time delay in usec before Rx interrupt */
 static void mvpp2_rx_time_coal_set(struct mvpp2_port *port,
 				   struct mvpp2_rx_queue *rxq)
 {
-	unsigned long freq = port->priv->tclk;
+	u32 freq = port->priv->tclk;
 	u32 val = mvpp2_usec_to_cycles(rxq->time_coal, freq);
 
 	if (val > MVPP2_MAX_ISR_RX_THRESHOLD) {
@@ -2804,7 +2804,7 @@ static void mvpp2_rx_time_coal_set(struct mvpp2_port *port,
 
 static void mvpp2_tx_time_coal_set(struct mvpp2_port *port)
 {
-	unsigned long freq = port->priv->tclk;
+	u32 freq = port->priv->tclk;
 	u32 val = mvpp2_usec_to_cycles(port->tx_time_coal, freq);
 
 	if (val > MVPP2_MAX_ISR_TX_THRESHOLD) {