1/***********************license start***************
2 * Author: Cavium Networks
3 *
4 * Contact: support@caviumnetworks.com
5 * This file is part of the OCTEON SDK
6 *
7 * Copyright (c) 2003-2008 Cavium Networks
8 *
9 * This file is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License, Version 2, as
11 * published by the Free Software Foundation.
12 *
13 * This file is distributed in the hope that it will be useful, but
14 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
15 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
16 * NONINFRINGEMENT.  See the GNU General Public License for more
17 * details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this file; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 * or visit http://www.gnu.org/licenses/.
23 *
24 * This file may also be available under a different license from Cavium.
25 * Contact Cavium Networks for more information
26 ***********************license end**************************************/
27
28/**
29 *
30 * Fixes and workaround for Octeon chip errata. This file
31 * contains functions called by cvmx-helper to workaround known
32 * chip errata. For the most part, code doesn't need to call
33 * these functions directly.
34 *
35 */
36#include <linux/module.h>
37
38#include <asm/octeon/octeon.h>
39
40#include <asm/octeon/cvmx-helper-jtag.h>
41
42/**
43 * Due to errata G-720, the 2nd order CDR circuit on CN52XX pass
44 * 1 doesn't work properly. The following code disables 2nd order
45 * CDR for the specified QLM.
46 *
47 * @qlm:    QLM to disable 2nd order CDR for.
48 */
49void __cvmx_helper_errata_qlm_disable_2nd_order_cdr(int qlm)
50{
51	int lane;
52	cvmx_helper_qlm_jtag_init();
53	/* We need to load all four lanes of the QLM, a total of 1072 bits */
54	for (lane = 0; lane < 4; lane++) {
55		/*
56		 * Each lane has 268 bits. We need to set
57		 * cfg_cdr_incx<67:64> = 3 and cfg_cdr_secord<77> =
58		 * 1. All other bits are zero. Bits go in LSB first,
59		 * so start off with the zeros for bits <63:0>.
60		 */
61		cvmx_helper_qlm_jtag_shift_zeros(qlm, 63 - 0 + 1);
62		/* cfg_cdr_incx<67:64>=3 */
63		cvmx_helper_qlm_jtag_shift(qlm, 67 - 64 + 1, 3);
64		/* Zeros for bits <76:68> */
65		cvmx_helper_qlm_jtag_shift_zeros(qlm, 76 - 68 + 1);
66		/* cfg_cdr_secord<77>=1 */
67		cvmx_helper_qlm_jtag_shift(qlm, 77 - 77 + 1, 1);
68		/* Zeros for bits <267:78> */
69		cvmx_helper_qlm_jtag_shift_zeros(qlm, 267 - 78 + 1);
70	}
71	cvmx_helper_qlm_jtag_update(qlm);
72}
73EXPORT_SYMBOL(__cvmx_helper_errata_qlm_disable_2nd_order_cdr);
74