MIPS: Add Cavium OCTEON PCI support.

This patch adds support for PCI and PCIe to the base Cavium OCTEON
processor support.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

3 files changed, 215 insertions, 0 deletions

diff --git a/arch/mips/cavium-octeon/executive/Makefile b/arch/mips/cavium-octeon/executive/Makefile
index 80d6cb26766b..2fd66db6939e 100644
--- a/arch/mips/cavium-octeon/executive/Makefile
+++ b/arch/mips/cavium-octeon/executive/Makefile
@@ -11,3 +11,4 @@
 
 obj-y += cvmx-bootmem.o cvmx-l2c.o cvmx-sysinfo.o octeon-model.o
 
+obj-$(CONFIG_PCI) += cvmx-helper-errata.o cvmx-helper-jtag.o
diff --git a/arch/mips/cavium-octeon/executive/cvmx-helper-errata.c b/arch/mips/cavium-octeon/executive/cvmx-helper-errata.c
new file mode 100644
index 000000000000..8fb82057cd80
--- /dev/null
+++ b/arch/mips/cavium-octeon/executive/cvmx-helper-errata.c
@@ -0,0 +1,70 @@
+/***********************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**************************************/
+
+/**
+ *
+ * Fixes and workaround for Octeon chip errata. This file
+ * contains functions called by cvmx-helper to workaround known
+ * chip errata. For the most part, code doesn't need to call
+ * these functions directly.
+ *
+ */
+#include <asm/octeon/octeon.h>
+
+#include <asm/octeon/cvmx-helper-jtag.h>
+
+/**
+ * Due to errata G-720, the 2nd order CDR circuit on CN52XX pass
+ * 1 doesn't work properly. The following code disables 2nd order
+ * CDR for the specified QLM.
+ *
+ * @qlm:    QLM to disable 2nd order CDR for.
+ */
+void __cvmx_helper_errata_qlm_disable_2nd_order_cdr(int qlm)
+{
+	int lane;
+	cvmx_helper_qlm_jtag_init();
+	/* We need to load all four lanes of the QLM, a total of 1072 bits */
+	for (lane = 0; lane < 4; lane++) {
+		/*
+		 * Each lane has 268 bits. We need to set
+		 * cfg_cdr_incx<67:64> = 3 and cfg_cdr_secord<77> =
+		 * 1. All other bits are zero. Bits go in LSB first,
+		 * so start off with the zeros for bits <63:0>.
+		 */
+		cvmx_helper_qlm_jtag_shift_zeros(qlm, 63 - 0 + 1);
+		/* cfg_cdr_incx<67:64>=3 */
+		cvmx_helper_qlm_jtag_shift(qlm, 67 - 64 + 1, 3);
+		/* Zeros for bits <76:68> */
+		cvmx_helper_qlm_jtag_shift_zeros(qlm, 76 - 68 + 1);
+		/* cfg_cdr_secord<77>=1 */
+		cvmx_helper_qlm_jtag_shift(qlm, 77 - 77 + 1, 1);
+		/* Zeros for bits <267:78> */
+		cvmx_helper_qlm_jtag_shift_zeros(qlm, 267 - 78 + 1);
+	}
+	cvmx_helper_qlm_jtag_update(qlm);
+}
diff --git a/arch/mips/cavium-octeon/executive/cvmx-helper-jtag.c b/arch/mips/cavium-octeon/executive/cvmx-helper-jtag.c
new file mode 100644
index 000000000000..c1c54890bae0
--- /dev/null
+++ b/arch/mips/cavium-octeon/executive/cvmx-helper-jtag.c
@@ -0,0 +1,144 @@
+
+/***********************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**************************************/
+
+/**
+ *
+ * Helper utilities for qlm_jtag.
+ *
+ */
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-helper-jtag.h>
+
+
+/**
+ * Initialize the internal QLM JTAG logic to allow programming
+ * of the JTAG chain by the cvmx_helper_qlm_jtag_*() functions.
+ * These functions should only be used at the direction of Cavium
+ * Networks. Programming incorrect values into the JTAG chain
+ * can cause chip damage.
+ */
+void cvmx_helper_qlm_jtag_init(void)
+{
+	union cvmx_ciu_qlm_jtgc jtgc;
+	uint32_t clock_div = 0;
+	uint32_t divisor = cvmx_sysinfo_get()->cpu_clock_hz / (25 * 1000000);
+	divisor = (divisor - 1) >> 2;
+	/* Convert the divisor into a power of 2 shift */
+	while (divisor) {
+		clock_div++;
+		divisor = divisor >> 1;
+	}
+
+	/*
+	 * Clock divider for QLM JTAG operations.  eclk is divided by
+	 * 2^(CLK_DIV + 2)
+	 */
+	jtgc.u64 = 0;
+	jtgc.s.clk_div = clock_div;
+	jtgc.s.mux_sel = 0;
+	if (OCTEON_IS_MODEL(OCTEON_CN52XX))
+		jtgc.s.bypass = 0x3;
+	else
+		jtgc.s.bypass = 0xf;
+	cvmx_write_csr(CVMX_CIU_QLM_JTGC, jtgc.u64);
+	cvmx_read_csr(CVMX_CIU_QLM_JTGC);
+}
+
+/**
+ * Write up to 32bits into the QLM jtag chain. Bits are shifted
+ * into the MSB and out the LSB, so you should shift in the low
+ * order bits followed by the high order bits. The JTAG chain is
+ * 4 * 268 bits long, or 1072.
+ *
+ * @qlm:    QLM to shift value into
+ * @bits:   Number of bits to shift in (1-32).
+ * @data:   Data to shift in. Bit 0 enters the chain first, followed by
+ *               bit 1, etc.
+ *
+ * Returns The low order bits of the JTAG chain that shifted out of the
+ *         circle.
+ */
+uint32_t cvmx_helper_qlm_jtag_shift(int qlm, int bits, uint32_t data)
+{
+	union cvmx_ciu_qlm_jtgd jtgd;
+	jtgd.u64 = 0;
+	jtgd.s.shift = 1;
+	jtgd.s.shft_cnt = bits - 1;
+	jtgd.s.shft_reg = data;
+	if (!OCTEON_IS_MODEL(OCTEON_CN56XX_PASS1_X))
+		jtgd.s.select = 1 << qlm;
+	cvmx_write_csr(CVMX_CIU_QLM_JTGD, jtgd.u64);
+	do {
+		jtgd.u64 = cvmx_read_csr(CVMX_CIU_QLM_JTGD);
+	} while (jtgd.s.shift);
+	return jtgd.s.shft_reg >> (32 - bits);
+}
+
+/**
+ * Shift long sequences of zeros into the QLM JTAG chain. It is
+ * common to need to shift more than 32 bits of zeros into the
+ * chain. This function is a convience wrapper around
+ * cvmx_helper_qlm_jtag_shift() to shift more than 32 bits of
+ * zeros at a time.
+ *
+ * @qlm:    QLM to shift zeros into
+ * @bits:
+ */
+void cvmx_helper_qlm_jtag_shift_zeros(int qlm, int bits)
+{
+	while (bits > 0) {
+		int n = bits;
+		if (n > 32)
+			n = 32;
+		cvmx_helper_qlm_jtag_shift(qlm, n, 0);
+		bits -= n;
+	}
+}
+
+/**
+ * Program the QLM JTAG chain into all lanes of the QLM. You must
+ * have already shifted in 268*4, or 1072 bits into the JTAG
+ * chain. Updating invalid values can possibly cause chip damage.
+ *
+ * @qlm:    QLM to program
+ */
+void cvmx_helper_qlm_jtag_update(int qlm)
+{
+	union cvmx_ciu_qlm_jtgd jtgd;
+
+	/* Update the new data */
+	jtgd.u64 = 0;
+	jtgd.s.update = 1;
+	if (!OCTEON_IS_MODEL(OCTEON_CN56XX_PASS1_X))
+		jtgd.s.select = 1 << qlm;
+	cvmx_write_csr(CVMX_CIU_QLM_JTGD, jtgd.u64);
+	do {
+		jtgd.u64 = cvmx_read_csr(CVMX_CIU_QLM_JTGD);
+	} while (jtgd.s.update);
+}