Initial import

1 files changed, 526 insertions, 0 deletions

diff --git a/arch/mips/cavium-octeon/executive/cvmx-helper-rgmii.c b/arch/mips/cavium-octeon/executive/cvmx-helper-rgmii.c
new file mode 100644
index 000000000..f59c88ee9
--- /dev/null
+++ b/arch/mips/cavium-octeon/executive/cvmx-helper-rgmii.c
@@ -0,0 +1,526 @@
+/***********************license start***************
+ * Author: Cavium Networks
+ *
+ * Contact: support@caviumnetworks.com
+ * This file is part of the OCTEON SDK
+ *
+ * Copyright (c) 2003-2008 Cavium Networks
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, Version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
+ * NONINFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this file; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ * or visit http://www.gnu.org/licenses/.
+ *
+ * This file may also be available under a different license from Cavium.
+ * Contact Cavium Networks for more information
+ ***********************license end**************************************/
+
+/*
+ * Functions for RGMII/GMII/MII initialization, configuration,
+ * and monitoring.
+ */
+#include <asm/octeon/octeon.h>
+
+#include <asm/octeon/cvmx-config.h>
+
+
+#include <asm/octeon/cvmx-mdio.h>
+#include <asm/octeon/cvmx-pko.h>
+#include <asm/octeon/cvmx-helper.h>
+#include <asm/octeon/cvmx-helper-board.h>
+
+#include <asm/octeon/cvmx-npi-defs.h>
+#include <asm/octeon/cvmx-gmxx-defs.h>
+#include <asm/octeon/cvmx-asxx-defs.h>
+#include <asm/octeon/cvmx-dbg-defs.h>
+
+void __cvmx_interrupt_gmxx_enable(int interface);
+void __cvmx_interrupt_asxx_enable(int block);
+
+/**
+ * Probe RGMII ports and determine the number present
+ *
+ * @interface: Interface to probe
+ *
+ * Returns Number of RGMII/GMII/MII ports (0-4).
+ */
+int __cvmx_helper_rgmii_probe(int interface)
+{
+	int num_ports = 0;
+	union cvmx_gmxx_inf_mode mode;
+	mode.u64 = cvmx_read_csr(CVMX_GMXX_INF_MODE(interface));
+
+	if (mode.s.type) {
+		if (OCTEON_IS_MODEL(OCTEON_CN38XX)
+		    || OCTEON_IS_MODEL(OCTEON_CN58XX)) {
+			cvmx_dprintf("ERROR: RGMII initialize called in "
+				     "SPI interface\n");
+		} else if (OCTEON_IS_MODEL(OCTEON_CN31XX)
+			   || OCTEON_IS_MODEL(OCTEON_CN30XX)
+			   || OCTEON_IS_MODEL(OCTEON_CN50XX)) {
+			/*
+			 * On these chips "type" says we're in
+			 * GMII/MII mode. This limits us to 2 ports
+			 */
+			num_ports = 2;
+		} else {
+			cvmx_dprintf("ERROR: Unsupported Octeon model in %s\n",
+				     __func__);
+		}
+	} else {
+		if (OCTEON_IS_MODEL(OCTEON_CN38XX)
+		    || OCTEON_IS_MODEL(OCTEON_CN58XX)) {
+			num_ports = 4;
+		} else if (OCTEON_IS_MODEL(OCTEON_CN31XX)
+			   || OCTEON_IS_MODEL(OCTEON_CN30XX)
+			   || OCTEON_IS_MODEL(OCTEON_CN50XX)) {
+			num_ports = 3;
+		} else {
+			cvmx_dprintf("ERROR: Unsupported Octeon model in %s\n",
+				     __func__);
+		}
+	}
+	return num_ports;
+}
+
+/**
+ * Put an RGMII interface in loopback mode. Internal packets sent
+ * out will be received back again on the same port. Externally
+ * received packets will echo back out.
+ *
+ * @port:   IPD port number to loop.
+ */
+void cvmx_helper_rgmii_internal_loopback(int port)
+{
+	int interface = (port >> 4) & 1;
+	int index = port & 0xf;
+	uint64_t tmp;
+
+	union cvmx_gmxx_prtx_cfg gmx_cfg;
+	gmx_cfg.u64 = 0;
+	gmx_cfg.s.duplex = 1;
+	gmx_cfg.s.slottime = 1;
+	gmx_cfg.s.speed = 1;
+	cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 1);
+	cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x200);
+	cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0x2000);
+	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64);
+	tmp = cvmx_read_csr(CVMX_ASXX_PRT_LOOP(interface));
+	cvmx_write_csr(CVMX_ASXX_PRT_LOOP(interface), (1 << index) | tmp);
+	tmp = cvmx_read_csr(CVMX_ASXX_TX_PRT_EN(interface));
+	cvmx_write_csr(CVMX_ASXX_TX_PRT_EN(interface), (1 << index) | tmp);
+	tmp = cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface));
+	cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface), (1 << index) | tmp);
+	gmx_cfg.s.en = 1;
+	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64);
+}
+
+/**
+ * Workaround ASX setup errata with CN38XX pass1
+ *
+ * @interface: Interface to setup
+ * @port:      Port to setup (0..3)
+ * @cpu_clock_hz:
+ *		    Chip frequency in Hertz
+ *
+ * Returns Zero on success, negative on failure
+ */
+static int __cvmx_helper_errata_asx_pass1(int interface, int port,
+					  int cpu_clock_hz)
+{
+	/* Set hi water mark as per errata GMX-4 */
+	if (cpu_clock_hz >= 325000000 && cpu_clock_hz < 375000000)
+		cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 12);
+	else if (cpu_clock_hz >= 375000000 && cpu_clock_hz < 437000000)
+		cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 11);
+	else if (cpu_clock_hz >= 437000000 && cpu_clock_hz < 550000000)
+		cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 10);
+	else if (cpu_clock_hz >= 550000000 && cpu_clock_hz < 687000000)
+		cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 9);
+	else
+		cvmx_dprintf("Illegal clock frequency (%d). "
+			"CVMX_ASXX_TX_HI_WATERX not set\n", cpu_clock_hz);
+	return 0;
+}
+
+/**
+ * Configure all of the ASX, GMX, and PKO regsiters required
+ * to get RGMII to function on the supplied interface.
+ *
+ * @interface: PKO Interface to configure (0 or 1)
+ *
+ * Returns Zero on success
+ */
+int __cvmx_helper_rgmii_enable(int interface)
+{
+	int num_ports = cvmx_helper_ports_on_interface(interface);
+	int port;
+	struct cvmx_sysinfo *sys_info_ptr = cvmx_sysinfo_get();
+	union cvmx_gmxx_inf_mode mode;
+	union cvmx_asxx_tx_prt_en asx_tx;
+	union cvmx_asxx_rx_prt_en asx_rx;
+
+	mode.u64 = cvmx_read_csr(CVMX_GMXX_INF_MODE(interface));
+
+	if (mode.s.en == 0)
+		return -1;
+	if ((OCTEON_IS_MODEL(OCTEON_CN38XX) ||
+	     OCTEON_IS_MODEL(OCTEON_CN58XX)) && mode.s.type == 1)
+		/* Ignore SPI interfaces */
+		return -1;
+
+	/* Configure the ASX registers needed to use the RGMII ports */
+	asx_tx.u64 = 0;
+	asx_tx.s.prt_en = cvmx_build_mask(num_ports);
+	cvmx_write_csr(CVMX_ASXX_TX_PRT_EN(interface), asx_tx.u64);
+
+	asx_rx.u64 = 0;
+	asx_rx.s.prt_en = cvmx_build_mask(num_ports);
+	cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface), asx_rx.u64);
+
+	/* Configure the GMX registers needed to use the RGMII ports */
+	for (port = 0; port < num_ports; port++) {
+		/* Setting of CVMX_GMXX_TXX_THRESH has been moved to
+		   __cvmx_helper_setup_gmx() */
+
+		if (cvmx_octeon_is_pass1())
+			__cvmx_helper_errata_asx_pass1(interface, port,
+						       sys_info_ptr->
+						       cpu_clock_hz);
+		else {
+			/*
+			 * Configure more flexible RGMII preamble
+			 * checking. Pass 1 doesn't support this
+			 * feature.
+			 */
+			union cvmx_gmxx_rxx_frm_ctl frm_ctl;
+			frm_ctl.u64 =
+			    cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL
+					  (port, interface));
+			/* New field, so must be compile time */
+			frm_ctl.s.pre_free = 1;
+			cvmx_write_csr(CVMX_GMXX_RXX_FRM_CTL(port, interface),
+				       frm_ctl.u64);
+		}
+
+		/*
+		 * Each pause frame transmitted will ask for about 10M
+		 * bit times before resume.  If buffer space comes
+		 * available before that time has expired, an XON
+		 * pause frame (0 time) will be transmitted to restart
+		 * the flow.
+		 */
+		cvmx_write_csr(CVMX_GMXX_TXX_PAUSE_PKT_TIME(port, interface),
+			       20000);
+		cvmx_write_csr(CVMX_GMXX_TXX_PAUSE_PKT_INTERVAL
+			       (port, interface), 19000);
+
+		if (OCTEON_IS_MODEL(OCTEON_CN50XX)) {
+			cvmx_write_csr(CVMX_ASXX_TX_CLK_SETX(port, interface),
+				       16);
+			cvmx_write_csr(CVMX_ASXX_RX_CLK_SETX(port, interface),
+				       16);
+		} else {
+			cvmx_write_csr(CVMX_ASXX_TX_CLK_SETX(port, interface),
+				       24);
+			cvmx_write_csr(CVMX_ASXX_RX_CLK_SETX(port, interface),
+				       24);
+		}
+	}
+
+	__cvmx_helper_setup_gmx(interface, num_ports);
+
+	/* enable the ports now */
+	for (port = 0; port < num_ports; port++) {
+		union cvmx_gmxx_prtx_cfg gmx_cfg;
+		cvmx_helper_link_autoconf(cvmx_helper_get_ipd_port
+					  (interface, port));
+		gmx_cfg.u64 =
+		    cvmx_read_csr(CVMX_GMXX_PRTX_CFG(port, interface));
+		gmx_cfg.s.en = 1;
+		cvmx_write_csr(CVMX_GMXX_PRTX_CFG(port, interface),
+			       gmx_cfg.u64);
+	}
+	__cvmx_interrupt_asxx_enable(interface);
+	__cvmx_interrupt_gmxx_enable(interface);
+
+	return 0;
+}
+
+/**
+ * Return the link state of an IPD/PKO port as returned by
+ * auto negotiation. The result of this function may not match
+ * Octeon's link config if auto negotiation has changed since
+ * the last call to cvmx_helper_link_set().
+ *
+ * @ipd_port: IPD/PKO port to query
+ *
+ * Returns Link state
+ */
+cvmx_helper_link_info_t __cvmx_helper_rgmii_link_get(int ipd_port)
+{
+	int interface = cvmx_helper_get_interface_num(ipd_port);
+	int index = cvmx_helper_get_interface_index_num(ipd_port);
+	union cvmx_asxx_prt_loop asxx_prt_loop;
+
+	asxx_prt_loop.u64 = cvmx_read_csr(CVMX_ASXX_PRT_LOOP(interface));
+	if (asxx_prt_loop.s.int_loop & (1 << index)) {
+		/* Force 1Gbps full duplex on internal loopback */
+		cvmx_helper_link_info_t result;
+		result.u64 = 0;
+		result.s.full_duplex = 1;
+		result.s.link_up = 1;
+		result.s.speed = 1000;
+		return result;
+	} else
+		return __cvmx_helper_board_link_get(ipd_port);
+}
+
+/**
+ * Configure an IPD/PKO port for the specified link state. This
+ * function does not influence auto negotiation at the PHY level.
+ * The passed link state must always match the link state returned
+ * by cvmx_helper_link_get(). It is normally best to use
+ * cvmx_helper_link_autoconf() instead.
+ *
+ * @ipd_port:  IPD/PKO port to configure
+ * @link_info: The new link state
+ *
+ * Returns Zero on success, negative on failure
+ */
+int __cvmx_helper_rgmii_link_set(int ipd_port,
+				 cvmx_helper_link_info_t link_info)
+{
+	int result = 0;
+	int interface = cvmx_helper_get_interface_num(ipd_port);
+	int index = cvmx_helper_get_interface_index_num(ipd_port);
+	union cvmx_gmxx_prtx_cfg original_gmx_cfg;
+	union cvmx_gmxx_prtx_cfg new_gmx_cfg;
+	union cvmx_pko_mem_queue_qos pko_mem_queue_qos;
+	union cvmx_pko_mem_queue_qos pko_mem_queue_qos_save[16];
+	union cvmx_gmxx_tx_ovr_bp gmx_tx_ovr_bp;
+	union cvmx_gmxx_tx_ovr_bp gmx_tx_ovr_bp_save;
+	int i;
+
+	/* Ignore speed sets in the simulator */
+	if (cvmx_sysinfo_get()->board_type == CVMX_BOARD_TYPE_SIM)
+		return 0;
+
+	/* Read the current settings so we know the current enable state */
+	original_gmx_cfg.u64 =
+	    cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
+	new_gmx_cfg = original_gmx_cfg;
+
+	/* Disable the lowest level RX */
+	cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface),
+		       cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface)) &
+				     ~(1 << index));
+
+	memset(pko_mem_queue_qos_save, 0, sizeof(pko_mem_queue_qos_save));
+	/* Disable all queues so that TX should become idle */
+	for (i = 0; i < cvmx_pko_get_num_queues(ipd_port); i++) {
+		int queue = cvmx_pko_get_base_queue(ipd_port) + i;
+		cvmx_write_csr(CVMX_PKO_REG_READ_IDX, queue);
+		pko_mem_queue_qos.u64 = cvmx_read_csr(CVMX_PKO_MEM_QUEUE_QOS);
+		pko_mem_queue_qos.s.pid = ipd_port;
+		pko_mem_queue_qos.s.qid = queue;
+		pko_mem_queue_qos_save[i] = pko_mem_queue_qos;
+		pko_mem_queue_qos.s.qos_mask = 0;
+		cvmx_write_csr(CVMX_PKO_MEM_QUEUE_QOS, pko_mem_queue_qos.u64);
+	}
+
+	/* Disable backpressure */
+	gmx_tx_ovr_bp.u64 = cvmx_read_csr(CVMX_GMXX_TX_OVR_BP(interface));
+	gmx_tx_ovr_bp_save = gmx_tx_ovr_bp;
+	gmx_tx_ovr_bp.s.bp &= ~(1 << index);
+	gmx_tx_ovr_bp.s.en |= 1 << index;
+	cvmx_write_csr(CVMX_GMXX_TX_OVR_BP(interface), gmx_tx_ovr_bp.u64);
+	cvmx_read_csr(CVMX_GMXX_TX_OVR_BP(interface));
+
+	/*
+	 * Poll the GMX state machine waiting for it to become
+	 * idle. Preferably we should only change speed when it is
+	 * idle. If it doesn't become idle we will still do the speed
+	 * change, but there is a slight chance that GMX will
+	 * lockup.
+	 */
+	cvmx_write_csr(CVMX_NPI_DBG_SELECT,
+		       interface * 0x800 + index * 0x100 + 0x880);
+	CVMX_WAIT_FOR_FIELD64(CVMX_DBG_DATA, union cvmx_dbg_data, data & 7,
+			==, 0, 10000);
+	CVMX_WAIT_FOR_FIELD64(CVMX_DBG_DATA, union cvmx_dbg_data, data & 0xf,
+			==, 0, 10000);
+
+	/* Disable the port before we make any changes */
+	new_gmx_cfg.s.en = 0;
+	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), new_gmx_cfg.u64);
+	cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
+
+	/* Set full/half duplex */
+	if (cvmx_octeon_is_pass1())
+		/* Half duplex is broken for 38XX Pass 1 */
+		new_gmx_cfg.s.duplex = 1;
+	else if (!link_info.s.link_up)
+		/* Force full duplex on down links */
+		new_gmx_cfg.s.duplex = 1;
+	else
+		new_gmx_cfg.s.duplex = link_info.s.full_duplex;
+
+	/* Set the link speed. Anything unknown is set to 1Gbps */
+	if (link_info.s.speed == 10) {
+		new_gmx_cfg.s.slottime = 0;
+		new_gmx_cfg.s.speed = 0;
+	} else if (link_info.s.speed == 100) {
+		new_gmx_cfg.s.slottime = 0;
+		new_gmx_cfg.s.speed = 0;
+	} else {
+		new_gmx_cfg.s.slottime = 1;
+		new_gmx_cfg.s.speed = 1;
+	}
+
+	/* Adjust the clocks */
+	if (link_info.s.speed == 10) {
+		cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 50);
+		cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x40);
+		cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0);
+	} else if (link_info.s.speed == 100) {
+		cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 5);
+		cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x40);
+		cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0);
+	} else {
+		cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 1);
+		cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x200);
+		cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0x2000);
+	}
+
+	if (OCTEON_IS_MODEL(OCTEON_CN30XX) || OCTEON_IS_MODEL(OCTEON_CN50XX)) {
+		if ((link_info.s.speed == 10) || (link_info.s.speed == 100)) {
+			union cvmx_gmxx_inf_mode mode;
+			mode.u64 = cvmx_read_csr(CVMX_GMXX_INF_MODE(interface));
+
+	/*
+	 * Port	 .en  .type  .p0mii  Configuration
+	 * ----	 ---  -----  ------  -----------------------------------------
+	 *  X	   0	 X	X    All links are disabled.
+	 *  0	   1	 X	0    Port 0 is RGMII
+	 *  0	   1	 X	1    Port 0 is MII
+	 *  1	   1	 0	X    Ports 1 and 2 are configured as RGMII ports.
+	 *  1	   1	 1	X    Port 1: GMII/MII; Port 2: disabled. GMII or
+	 *			     MII port is selected by GMX_PRT1_CFG[SPEED].
+	 */
+
+			/* In MII mode, CLK_CNT = 1. */
+			if (((index == 0) && (mode.s.p0mii == 1))
+			    || ((index != 0) && (mode.s.type == 1))) {
+				cvmx_write_csr(CVMX_GMXX_TXX_CLK
+					       (index, interface), 1);
+			}
+		}
+	}
+
+	/* Do a read to make sure all setup stuff is complete */
+	cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
+
+	/* Save the new GMX setting without enabling the port */
+	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), new_gmx_cfg.u64);
+
+	/* Enable the lowest level RX */
+	cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface),
+		       cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface)) | (1 <<
+									index));
+
+	/* Re-enable the TX path */
+	for (i = 0; i < cvmx_pko_get_num_queues(ipd_port); i++) {
+		int queue = cvmx_pko_get_base_queue(ipd_port) + i;
+		cvmx_write_csr(CVMX_PKO_REG_READ_IDX, queue);
+		cvmx_write_csr(CVMX_PKO_MEM_QUEUE_QOS,
+			       pko_mem_queue_qos_save[i].u64);
+	}
+
+	/* Restore backpressure */
+	cvmx_write_csr(CVMX_GMXX_TX_OVR_BP(interface), gmx_tx_ovr_bp_save.u64);
+
+	/* Restore the GMX enable state. Port config is complete */
+	new_gmx_cfg.s.en = original_gmx_cfg.s.en;
+	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), new_gmx_cfg.u64);
+
+	return result;
+}
+
+/**
+ * Configure a port for internal and/or external loopback. Internal loopback
+ * causes packets sent by the port to be received by Octeon. External loopback
+ * causes packets received from the wire to sent out again.
+ *
+ * @ipd_port: IPD/PKO port to loopback.
+ * @enable_internal:
+ *		   Non zero if you want internal loopback
+ * @enable_external:
+ *		   Non zero if you want external loopback
+ *
+ * Returns Zero on success, negative on failure.
+ */
+int __cvmx_helper_rgmii_configure_loopback(int ipd_port, int enable_internal,
+					   int enable_external)
+{
+	int interface = cvmx_helper_get_interface_num(ipd_port);
+	int index = cvmx_helper_get_interface_index_num(ipd_port);
+	int original_enable;
+	union cvmx_gmxx_prtx_cfg gmx_cfg;
+	union cvmx_asxx_prt_loop asxx_prt_loop;
+
+	/* Read the current enable state and save it */
+	gmx_cfg.u64 = cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
+	original_enable = gmx_cfg.s.en;
+	/* Force port to be disabled */
+	gmx_cfg.s.en = 0;
+	if (enable_internal) {
+		/* Force speed if we're doing internal loopback */
+		gmx_cfg.s.duplex = 1;
+		gmx_cfg.s.slottime = 1;
+		gmx_cfg.s.speed = 1;
+		cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 1);
+		cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x200);
+		cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0x2000);
+	}
+	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64);
+
+	/* Set the loopback bits */
+	asxx_prt_loop.u64 = cvmx_read_csr(CVMX_ASXX_PRT_LOOP(interface));
+	if (enable_internal)
+		asxx_prt_loop.s.int_loop |= 1 << index;
+	else
+		asxx_prt_loop.s.int_loop &= ~(1 << index);
+	if (enable_external)
+		asxx_prt_loop.s.ext_loop |= 1 << index;
+	else
+		asxx_prt_loop.s.ext_loop &= ~(1 << index);
+	cvmx_write_csr(CVMX_ASXX_PRT_LOOP(interface), asxx_prt_loop.u64);
+
+	/* Force enables in internal loopback */
+	if (enable_internal) {
+		uint64_t tmp;
+		tmp = cvmx_read_csr(CVMX_ASXX_TX_PRT_EN(interface));
+		cvmx_write_csr(CVMX_ASXX_TX_PRT_EN(interface),
+			       (1 << index) | tmp);
+		tmp = cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface));
+		cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface),
+			       (1 << index) | tmp);
+		original_enable = 1;
+	}
+
+	/* Restore the enable state */
+	gmx_cfg.s.en = original_enable;
+	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64);
+	return 0;
+}