sfc: Add a function pointer to abstract write of host time into NIC shared memory

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

drivers/net/ethernet/sfc/net_driver.h

@@ -1117,6 +1117,7 @@ struct efx_nic_type {
 			 size_t *retlen, const u8 *buffer);
 	int (*mtd_sync)(struct mtd_info *mtd);
 #endif
+	void (*ptp_write_host_time)(struct efx_nic *efx, u32 host_time);
 
 	int revision;
 	unsigned int txd_ptr_tbl_base;

drivers/net/ethernet/sfc/ptp.c

@@ -390,8 +390,7 @@ static void efx_ptp_send_times(struct efx_nic *efx,
 		host_time = (now.ts_real.tv_sec << MC_NANOSECOND_BITS |
 			     now.ts_real.tv_nsec);
 		/* Update host time in NIC memory */
-		_efx_writed(efx, cpu_to_le32(host_time),
-			    FR_CZ_MC_TREG_SMEM + MC_SMEM_P0_PTP_TIME_OFST);
+		efx->type->ptp_write_host_time(efx, host_time);
 	}
 	*last_time = now;
 }

drivers/net/ethernet/sfc/siena.c

@@ -853,6 +853,19 @@ static int siena_mtd_probe(struct efx_nic *efx)
 
 #endif /* CONFIG_SFC_MTD */
 
+/**************************************************************************
+ *
+ * PTP
+ *
+ **************************************************************************
+ */
+
+static void siena_ptp_write_host_time(struct efx_nic *efx, u32 host_time)
+{
+	_efx_writed(efx, cpu_to_le32(host_time),
+		    FR_CZ_MC_TREG_SMEM + MC_SMEM_P0_PTP_TIME_OFST);
+}
+
 /**************************************************************************
  *
  * Revision-dependent attributes used by efx.c and nic.c
@@ -943,6 +956,7 @@ const struct efx_nic_type siena_a0_nic_type = {
 	.mtd_write = efx_mcdi_mtd_write,
 	.mtd_sync = efx_mcdi_mtd_sync,
 #endif
+	.ptp_write_host_time = siena_ptp_write_host_time,
 
 	.revision = EFX_REV_SIENA_A0,
 	.txd_ptr_tbl_base = FR_BZ_TX_DESC_PTR_TBL,