nfp: add CPP access core

Command Push Pull is the name of NFP's network on a chip.
PCIe PF can access the interconnect through a number of mappings
controlled via Base Access Registers.  BARs allow the PF to issue
pretty much any command or address any memory on the chip.

Add appropriate logic and a handful of helper for simple operations
like reading scalars from memories.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/Makefile

 obj-$(CONFIG_NFP)	+= nfp.o
 
 nfp-objs := \
+	    nfpcore/nfp6000_pcie.o \
+	    nfpcore/nfp_cppcore.o \
+	    nfpcore/nfp_cpplib.o \
+	    nfpcore/nfp_target.o \
 	    nfp_main.o \
 	    nfp_net_common.o \
 	    nfp_net_ethtool.o \

drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000/nfp6000.h

+/*
+ * Copyright (C) 2015-2017 Netronome Systems, Inc.
+ *
+ * This software is dual licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree or the BSD 2-Clause License provided below.  You have the
+ * option to license this software under the complete terms of either license.
+ *
+ * The BSD 2-Clause License:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      1. Redistributions of source code must retain the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer.
+ *
+ *      2. Redistributions in binary form must reproduce the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer in the documentation and/or other materials
+ *         provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef NFP6000_NFP6000_H
+#define NFP6000_NFP6000_H
+
+#include <linux/errno.h>
+#include <linux/types.h>
+
+/* CPP Target IDs */
+#define NFP_CPP_TARGET_INVALID          0
+#define NFP_CPP_TARGET_NBI              1
+#define NFP_CPP_TARGET_QDR              2
+#define NFP_CPP_TARGET_ILA              6
+#define NFP_CPP_TARGET_MU               7
+#define NFP_CPP_TARGET_PCIE             9
+#define NFP_CPP_TARGET_ARM              10
+#define NFP_CPP_TARGET_CRYPTO           12
+#define NFP_CPP_TARGET_ISLAND_XPB       14      /* Shared with CAP */
+#define NFP_CPP_TARGET_ISLAND_CAP       14      /* Shared with XPB */
+#define NFP_CPP_TARGET_CT_XPB           14
+#define NFP_CPP_TARGET_LOCAL_SCRATCH    15
+#define NFP_CPP_TARGET_CLS              NFP_CPP_TARGET_LOCAL_SCRATCH
+
+#define NFP_ISL_EMEM0			24
+
+#define NFP_MU_ADDR_ACCESS_TYPE_MASK	3ULL
+#define NFP_MU_ADDR_ACCESS_TYPE_DIRECT	2ULL
+
+#define PUSHPULL(_pull, _push)		((_pull) << 4 | (_push) << 0)
+#define PUSH_WIDTH(_pushpull)		pushpull_width((_pushpull) >> 0)
+#define PULL_WIDTH(_pushpull)		pushpull_width((_pushpull) >> 4)
+
+static inline int pushpull_width(int pp)
+{
+	pp &= 0xf;
+
+	if (pp == 0)
+		return -EINVAL;
+	return 2 << pp;
+}
+
+static inline int nfp_cppat_mu_locality_lsb(int mode, bool addr40)
+{
+	switch (mode) {
+	case 0 ... 3:
+		return addr40 ? 38 : 30;
+	default:
+		return -EINVAL;
+	}
+}
+
+int nfp_target_pushpull(u32 cpp_id, u64 address);
+int nfp_target_cpp(u32 cpp_island_id, u64 cpp_island_address,
+		   u32 *cpp_target_id, u64 *cpp_target_address,
+		   const u32 *imb_table);
+
+#endif /* NFP6000_NFP6000_H */

drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000/nfp_xpb.h

+/*
+ * Copyright (C) 2015-2017 Netronome Systems, Inc.
+ *
+ * This software is dual licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree or the BSD 2-Clause License provided below.  You have the
+ * option to license this software under the complete terms of either license.
+ *
+ * The BSD 2-Clause License:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      1. Redistributions of source code must retain the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer.
+ *
+ *      2. Redistributions in binary form must reproduce the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer in the documentation and/or other materials
+ *         provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * nfp_xpb.h
+ * Author: Jason McMullan <jason.mcmullan@netronome.com>
+ */
+
+#ifndef NFP6000_XPB_H
+#define NFP6000_XPB_H
+
+/* For use with NFP6000 Databook "XPB Addressing" section
+ */
+#define NFP_XPB_OVERLAY(island)  (((island) & 0x3f) << 24)
+
+#define NFP_XPB_ISLAND(island)   (NFP_XPB_OVERLAY(island) + 0x60000)
+
+#define NFP_XPB_ISLAND_of(offset) (((offset) >> 24) & 0x3F)
+
+/* For use with NFP6000 Databook "XPB Island and Device IDs" chapter
+ */
+#define NFP_XPB_DEVICE(island, slave, device) \
+	(NFP_XPB_OVERLAY(island) | \
+	 (((slave) & 3) << 22) | \
+	 (((device) & 0x3f) << 16))
+
+#endif /* NFP6000_XPB_H */

drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.h

+/*
+ * Copyright (C) 2015-2017 Netronome Systems, Inc.
+ *
+ * This software is dual licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree or the BSD 2-Clause License provided below.  You have the
+ * option to license this software under the complete terms of either license.
+ *
+ * The BSD 2-Clause License:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      1. Redistributions of source code must retain the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer.
+ *
+ *      2. Redistributions in binary form must reproduce the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer in the documentation and/or other materials
+ *         provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * nfp6000_pcie.h
+ * Author: Jason McMullan <jason.mcmullan@netronome.com>
+ */
+
+#ifndef NFP6000_PCIE_H
+#define NFP6000_PCIE_H
+
+#include "nfp_cpp.h"
+
+struct nfp_cpp *nfp_cpp_from_nfp6000_pcie(struct pci_dev *pdev);
+
+#endif /* NFP6000_PCIE_H */

drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cpplib.c

+/*
+ * Copyright (C) 2015-2017 Netronome Systems, Inc.
+ *
+ * This software is dual licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree or the BSD 2-Clause License provided below.  You have the
+ * option to license this software under the complete terms of either license.
+ *
+ * The BSD 2-Clause License:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      1. Redistributions of source code must retain the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer.
+ *
+ *      2. Redistributions in binary form must reproduce the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer in the documentation and/or other materials
+ *         provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * nfp_cpplib.c
+ * Library of functions to access the NFP's CPP bus
+ * Authors: Jakub Kicinski <jakub.kicinski@netronome.com>
+ *          Jason McMullan <jason.mcmullan@netronome.com>
+ *          Rolf Neugebauer <rolf.neugebauer@netronome.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+
+#include "nfp_cpp.h"
+#include "nfp6000/nfp6000.h"
+#include "nfp6000/nfp_xpb.h"
+
+/* NFP6000 PL */
+#define NFP_PL_DEVICE_ID			0x00000004
+#define   NFP_PL_DEVICE_ID_MASK			GENMASK(7, 0)
+
+#define NFP6000_ARM_GCSR_SOFTMODEL0		0x00400144
+
+/**
+ * nfp_cpp_readl() - Read a u32 word from a CPP location
+ * @cpp:	CPP device handle
+ * @cpp_id:	CPP ID for operation
+ * @address:	Address for operation
+ * @value:	Pointer to read buffer
+ *
+ * Return: length of the io, or -ERRNO
+ */
+int nfp_cpp_readl(struct nfp_cpp *cpp, u32 cpp_id,
+		  unsigned long long address, u32 *value)
+{
+	u8 tmp[4];
+	int err;
+
+	err = nfp_cpp_read(cpp, cpp_id, address, tmp, sizeof(tmp));
+	*value = get_unaligned_le32(tmp);
+
+	return err;
+}
+
+/**
+ * nfp_cpp_writel() - Write a u32 word to a CPP location
+ * @cpp:	CPP device handle
+ * @cpp_id:	CPP ID for operation
+ * @address:	Address for operation
+ * @value:	Value to write
+ *
+ * Return: length of the io, or -ERRNO
+ */
+int nfp_cpp_writel(struct nfp_cpp *cpp, u32 cpp_id,
+		   unsigned long long address, u32 value)
+{
+	u8 tmp[4];
+
+	put_unaligned_le32(value, tmp);
+	return nfp_cpp_write(cpp, cpp_id, address, tmp, sizeof(tmp));
+}
+
+/**
+ * nfp_cpp_readq() - Read a u64 word from a CPP location
+ * @cpp:	CPP device handle
+ * @cpp_id:	CPP ID for operation
+ * @address:	Address for operation
+ * @value:	Pointer to read buffer
+ *
+ * Return: length of the io, or -ERRNO
+ */
+int nfp_cpp_readq(struct nfp_cpp *cpp, u32 cpp_id,
+		  unsigned long long address, u64 *value)
+{
+	u8 tmp[8];
+	int err;
+
+	err = nfp_cpp_read(cpp, cpp_id, address, tmp, sizeof(tmp));
+	*value = get_unaligned_le64(tmp);
+
+	return err;
+}
+
+/**
+ * nfp_cpp_writeq() - Write a u64 word to a CPP location
+ * @cpp:	CPP device handle
+ * @cpp_id:	CPP ID for operation
+ * @address:	Address for operation
+ * @value:	Value to write
+ *
+ * Return: length of the io, or -ERRNO
+ */
+int nfp_cpp_writeq(struct nfp_cpp *cpp, u32 cpp_id,
+		   unsigned long long address, u64 value)
+{
+	u8 tmp[8];
+
+	put_unaligned_le64(value, tmp);
+	return nfp_cpp_write(cpp, cpp_id, address, tmp, sizeof(tmp));
+}
+
+/* NOTE: This code should not use nfp_xpb_* functions,
+ * as those are model-specific
+ */
+int nfp_cpp_model_autodetect(struct nfp_cpp *cpp, u32 *model)
+{
+	const u32 arm_id = NFP_CPP_ID(NFP_CPP_TARGET_ARM, 0, 0);
+	u32 reg;
+	int err;
+
+	err = nfp_cpp_readl(cpp, arm_id, NFP6000_ARM_GCSR_SOFTMODEL0, model);
+	if (err < 0)
+		return err;
+
+	/* The PL's PluDeviceID revision code is authoratative */
+	*model &= ~0xff;
+	err = nfp_xpb_readl(cpp, NFP_XPB_DEVICE(1, 1, 16) + NFP_PL_DEVICE_ID,
+			    &reg);
+	if (err < 0)
+		return err;
+
+	*model |= (NFP_PL_DEVICE_ID_MASK & reg) - 0x10;
+
+	return 0;
+}
+
+static u8 nfp_bytemask(int width, u64 addr)
+{
+	if (width == 8)
+		return 0xff;
+	else if (width == 4)
+		return 0x0f << (addr & 4);
+	else if (width == 2)
+		return 0x03 << (addr & 6);
+	else if (width == 1)
+		return 0x01 << (addr & 7);
+	else
+		return 0;
+}
+
+int nfp_cpp_explicit_read(struct nfp_cpp *cpp, u32 cpp_id,
+			  u64 addr, void *buff, size_t len, int width_read)
+{
+	struct nfp_cpp_explicit *expl;
+	char *tmp = buff;
+	int err, i, incr;
+	u8 byte_mask;
+
+	if (len & (width_read - 1))
+		return -EINVAL;
+
+	expl = nfp_cpp_explicit_acquire(cpp);
+	if (!expl)
+		return -EBUSY;
+
+	incr = min_t(int, 16 * width_read, 128);
+	incr = min_t(int, incr, len);
+
+	/* Translate a NFP_CPP_ACTION_RW to action 0 */
+	if (NFP_CPP_ID_ACTION_of(cpp_id) == NFP_CPP_ACTION_RW)
+		cpp_id = NFP_CPP_ID(NFP_CPP_ID_TARGET_of(cpp_id), 0,
+				    NFP_CPP_ID_TOKEN_of(cpp_id));
+
+	byte_mask = nfp_bytemask(width_read, addr);
+
+	nfp_cpp_explicit_set_target(expl, cpp_id,
+				    incr / width_read - 1, byte_mask);
+	nfp_cpp_explicit_set_posted(expl, 1, 0, NFP_SIGNAL_PUSH,
+				    0, NFP_SIGNAL_NONE);
+
+	for (i = 0; i < len; i += incr, addr += incr, tmp += incr) {
+		if (i + incr > len) {
+			incr = len - i;
+			nfp_cpp_explicit_set_target(expl, cpp_id,
+						    incr / width_read - 1,
+						    0xff);
+		}
+
+		err = nfp_cpp_explicit_do(expl, addr);
+		if (err < 0)
+			goto exit_release;
+
+		err = nfp_cpp_explicit_get(expl, tmp, incr);
+		if (err < 0)
+			goto exit_release;
+	}
+	err = len;
+exit_release:
+	nfp_cpp_explicit_release(expl);
+
+	return err;
+}
+
+int nfp_cpp_explicit_write(struct nfp_cpp *cpp, u32 cpp_id, u64 addr,
+			   const void *buff, size_t len, int width_write)
+{
+	struct nfp_cpp_explicit *expl;
+	const char *tmp = buff;
+	int err, i, incr;
+	u8 byte_mask;
+
+	if (len & (width_write - 1))
+		return -EINVAL;
+
+	expl = nfp_cpp_explicit_acquire(cpp);
+	if (!expl)
+		return -EBUSY;
+
+	incr = min_t(int, 16 * width_write, 128);
+	incr = min_t(int, incr, len);
+
+	/* Translate a NFP_CPP_ACTION_RW to action 1 */
+	if (NFP_CPP_ID_ACTION_of(cpp_id) == NFP_CPP_ACTION_RW)
+		cpp_id = NFP_CPP_ID(NFP_CPP_ID_TARGET_of(cpp_id), 1,
+				    NFP_CPP_ID_TOKEN_of(cpp_id));
+
+	byte_mask = nfp_bytemask(width_write, addr);
+
+	nfp_cpp_explicit_set_target(expl, cpp_id,
+				    incr / width_write - 1, byte_mask);
+	nfp_cpp_explicit_set_posted(expl, 1, 0, NFP_SIGNAL_PULL,
+				    0, NFP_SIGNAL_NONE);
+
+	for (i = 0; i < len; i += incr, addr += incr, tmp += incr) {
+		if (i + incr > len) {
+			incr = len - i;
+			nfp_cpp_explicit_set_target(expl, cpp_id,
+						    incr / width_write - 1,
+						    0xff);
+		}
+
+		err = nfp_cpp_explicit_put(expl, tmp, incr);
+		if (err < 0)
+			goto exit_release;
+
+		err = nfp_cpp_explicit_do(expl, addr);
+		if (err < 0)
+			goto exit_release;
+	}
+	err = len;
+exit_release:
+	nfp_cpp_explicit_release(expl);
+
+	return err;
+}