nfp: add support for resources

Resource table is an array placed in a well defined location
in device's memory which describes device resources and contains
locks which have to be acquired to use them.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/Makefile

@@ -4,6 +4,7 @@ nfp-objs := \
 	    nfpcore/nfp6000_pcie.o \
 	    nfpcore/nfp_cppcore.o \
 	    nfpcore/nfp_cpplib.o \
+	    nfpcore/nfp_resource.o \
 	    nfpcore/nfp_target.o \
 	    nfp_main.o \
 	    nfp_net_common.o \

drivers/net/ethernet/netronome/nfp/nfpcore/crc32.h

@@ -0,0 +1,65 @@
+/*
+ * 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 NFP_CRC32_H
+#define NFP_CRC32_H
+
+#include <linux/kernel.h>
+#include <linux/crc32.h>
+
+/**
+ * crc32_posix_end() - Finalize POSIX CRC32 working state
+ * @crc:	Current CRC32 working state
+ * @total_len:	Total length of data that was CRC32'd
+ *
+ * Return: Final POSIX CRC32 value
+ */
+static inline u32 crc32_posix_end(u32 crc, size_t total_len)
+{
+	/* Extend with the length of the string. */
+	while (total_len != 0) {
+		u8 c = total_len & 0xff;
+
+		crc = crc32_be(crc, &c, 1);
+		total_len >>= 8;
+	}
+
+	return ~crc;
+}
+
+static inline u32 crc32_posix(const void *buff, size_t len)
+{
+	return crc32_posix_end(crc32_be(0, buff, len), len);
+}
+
+#endif /* NFP_CRC32_H */

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

@@ -0,0 +1,88 @@
+/*
+ * 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.h
+ * Interface for NFP device access and query functions.
+ */
+
+#ifndef __NFP_H__
+#define __NFP_H__
+
+#include <linux/device.h>
+
+#include "nfp_cpp.h"
+
+/* Implemented in nfp_resource.c */
+
+#define NFP_RESOURCE_TBL_TARGET		NFP_CPP_TARGET_MU
+#define NFP_RESOURCE_TBL_BASE		0x8100000000ULL
+
+/* NFP Resource Table self-identifier */
+#define NFP_RESOURCE_TBL_NAME		"nfp.res"
+#define NFP_RESOURCE_TBL_KEY		0x00000000 /* Special key for entry 0 */
+
+/* All other keys are CRC32-POSIX of the 8-byte identification string */
+
+/* ARM/PCI vNIC Interfaces 0..3 */
+#define NFP_RESOURCE_VNIC_PCI_0		"vnic.p0"
+#define NFP_RESOURCE_VNIC_PCI_1		"vnic.p1"
+#define NFP_RESOURCE_VNIC_PCI_2		"vnic.p2"
+#define NFP_RESOURCE_VNIC_PCI_3		"vnic.p3"
+
+/* NFP Hardware Info Database */
+#define NFP_RESOURCE_NFP_HWINFO		"nfp.info"
+
+/* Service Processor */
+#define NFP_RESOURCE_NSP		"nfp.sp"
+
+/* Netronone Flow Firmware Table */
+#define NFP_RESOURCE_NFP_NFFW		"nfp.nffw"
+
+/* MAC Statistics Accumulator */
+#define NFP_RESOURCE_MAC_STATISTICS	"mac.stat"
+
+struct nfp_resource *
+nfp_resource_acquire(struct nfp_cpp *cpp, const char *name);
+
+void nfp_resource_release(struct nfp_resource *res);
+
+u32 nfp_resource_cpp_id(struct nfp_resource *res);
+
+const char *nfp_resource_name(struct nfp_resource *res);
+
+u64 nfp_resource_address(struct nfp_resource *res);
+
+u64 nfp_resource_size(struct nfp_resource *res);
+
+#endif /* !__NFP_H__ */

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

@@ -0,0 +1,279 @@
+/*
+ * 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_resource.c
+ * Author: Jakub Kicinski <jakub.kicinski@netronome.com>
+ *         Jason McMullan <jason.mcmullan@netronome.com>
+ */
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "crc32.h"
+#include "nfp.h"
+#include "nfp_cpp.h"
+#include "nfp6000/nfp6000.h"
+
+#define NFP_RESOURCE_ENTRY_NAME_SZ	8
+
+/**
+ * struct nfp_resource_entry - Resource table entry
+ * @owner:		NFP CPP Lock, interface owner
+ * @key:		NFP CPP Lock, posix_crc32(name, 8)
+ * @region:		Memory region descriptor
+ * @name:		ASCII, zero padded name
+ * @reserved
+ * @cpp_action:		CPP Action
+ * @cpp_token:		CPP Token
+ * @cpp_target:		CPP Target ID
+ * @page_offset:	256-byte page offset into target's CPP address
+ * @page_size:		size, in 256-byte pages
+ */
+struct nfp_resource_entry {
+	struct nfp_resource_entry_mutex {
+		u32 owner;
+		u32 key;
+	} mutex;
+	struct nfp_resource_entry_region {
+		u8  name[NFP_RESOURCE_ENTRY_NAME_SZ];
+		u8  reserved[5];
+		u8  cpp_action;
+		u8  cpp_token;
+		u8  cpp_target;
+		u32 page_offset;
+		u32 page_size;
+	} region;
+};
+
+#define NFP_RESOURCE_TBL_SIZE		4096
+#define NFP_RESOURCE_TBL_ENTRIES	(NFP_RESOURCE_TBL_SIZE /	\
+					 sizeof(struct nfp_resource_entry))
+
+struct nfp_resource {
+	char name[NFP_RESOURCE_ENTRY_NAME_SZ + 1];
+	u32 cpp_id;
+	u64 addr;
+	u64 size;
+	struct nfp_cpp_mutex *mutex;
+};
+
+static int nfp_cpp_resource_find(struct nfp_cpp *cpp, struct nfp_resource *res)
+{
+	char name_pad[NFP_RESOURCE_ENTRY_NAME_SZ] = {};
+	struct nfp_resource_entry entry;
+	u32 cpp_id, key;
+	int ret, i;
+
+	cpp_id = NFP_CPP_ID(NFP_RESOURCE_TBL_TARGET, 3, 0);  /* Atomic read */
+
+	strncpy(name_pad, res->name, sizeof(name_pad));
+
+	/* Search for a matching entry */
+	key = NFP_RESOURCE_TBL_KEY;
+	if (memcmp(name_pad, NFP_RESOURCE_TBL_NAME "\0\0\0\0\0\0\0\0", 8))
+		key = crc32_posix(name_pad, sizeof(name_pad));
+
+	for (i = 0; i < NFP_RESOURCE_TBL_ENTRIES; i++) {
+		u64 addr = NFP_RESOURCE_TBL_BASE +
+			sizeof(struct nfp_resource_entry) * i;
+
+		ret = nfp_cpp_read(cpp, cpp_id, addr, &entry, sizeof(entry));
+		if (ret != sizeof(entry))
+			return -EIO;
+
+		if (entry.mutex.key != key)
+			continue;
+
+		/* Found key! */
+		res->mutex =
+			nfp_cpp_mutex_alloc(cpp,
+					    NFP_RESOURCE_TBL_TARGET, addr, key);
+		res->cpp_id = NFP_CPP_ID(entry.region.cpp_target,
+					 entry.region.cpp_action,
+					 entry.region.cpp_token);
+		res->addr = (u64)entry.region.page_offset << 8;
+		res->size = (u64)entry.region.page_size << 8;
+
+		return 0;
+	}
+
+	return -ENOENT;
+}
+
+static int
+nfp_resource_try_acquire(struct nfp_cpp *cpp, struct nfp_resource *res,
+			 struct nfp_cpp_mutex *dev_mutex)
+{
+	int err;
+
+	if (nfp_cpp_mutex_lock(dev_mutex))
+		return -EINVAL;
+
+	err = nfp_cpp_resource_find(cpp, res);
+	if (err)
+		goto err_unlock_dev;
+
+	err = nfp_cpp_mutex_trylock(res->mutex);
+	if (err)
+		goto err_res_mutex_free;
+
+	nfp_cpp_mutex_unlock(dev_mutex);
+
+	return 0;
+
+err_res_mutex_free:
+	nfp_cpp_mutex_free(res->mutex);
+err_unlock_dev:
+	nfp_cpp_mutex_unlock(dev_mutex);
+
+	return err;
+}
+
+/**
+ * nfp_resource_acquire() - Acquire a resource handle
+ * @cpp:	NFP CPP handle
+ * @name:	Name of the resource
+ *
+ * NOTE: This function locks the acquired resource
+ *
+ * Return: NFP Resource handle, or ERR_PTR()
+ */
+struct nfp_resource *
+nfp_resource_acquire(struct nfp_cpp *cpp, const char *name)
+{
+	unsigned long warn_at = jiffies + 15 * HZ;
+	struct nfp_cpp_mutex *dev_mutex;
+	struct nfp_resource *res;
+	int err;
+
+	res = kzalloc(sizeof(*res), GFP_KERNEL);
+	if (!res)
+		return ERR_PTR(-ENOMEM);
+
+	strncpy(res->name, name, NFP_RESOURCE_ENTRY_NAME_SZ);
+
+	dev_mutex = nfp_cpp_mutex_alloc(cpp, NFP_RESOURCE_TBL_TARGET,
+					NFP_RESOURCE_TBL_BASE,
+					NFP_RESOURCE_TBL_KEY);
+	if (!dev_mutex) {
+		kfree(res);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	for (;;) {
+		err = nfp_resource_try_acquire(cpp, res, dev_mutex);
+		if (!err)
+			break;
+		if (err != -EBUSY)
+			goto err_free;
+
+		err = msleep_interruptible(1);
+		if (err != 0) {
+			err = -ERESTARTSYS;
+			goto err_free;
+		}
+
+		if (time_is_before_eq_jiffies(warn_at)) {
+			warn_at = jiffies + 60 * HZ;
+			nfp_warn(cpp, "Warning: waiting for NFP resource %s\n",
+				 name);
+		}
+	}
+
+	nfp_cpp_mutex_free(dev_mutex);
+
+	return res;
+
+err_free:
+	nfp_cpp_mutex_free(dev_mutex);
+	kfree(res);
+	return ERR_PTR(err);
+}
+
+/**
+ * nfp_resource_release() - Release a NFP Resource handle
+ * @res:	NFP Resource handle
+ *
+ * NOTE: This function implictly unlocks the resource handle
+ */
+void nfp_resource_release(struct nfp_resource *res)
+{
+	nfp_cpp_mutex_unlock(res->mutex);
+	nfp_cpp_mutex_free(res->mutex);
+	kfree(res);
+}
+
+/**
+ * nfp_resource_cpp_id() - Return the cpp_id of a resource handle
+ * @res:	NFP Resource handle
+ *
+ * Return: NFP CPP ID
+ */
+u32 nfp_resource_cpp_id(struct nfp_resource *res)
+{
+	return res->cpp_id;
+}
+
+/**
+ * nfp_resource_name() - Return the name of a resource handle
+ * @res:	NFP Resource handle
+ *
+ * Return: const char pointer to the name of the resource
+ */
+const char *nfp_resource_name(struct nfp_resource *res)
+{
+	return res->name;
+}
+
+/**
+ * nfp_resource_address() - Return the address of a resource handle
+ * @res:	NFP Resource handle
+ *
+ * Return: Address of the resource
+ */
+u64 nfp_resource_address(struct nfp_resource *res)
+{
+	return res->addr;
+}
+
+/**
+ * nfp_resource_size() - Return the size in bytes of a resource handle
+ * @res:	NFP Resource handle
+ *
+ * Return: Size of the resource in bytes
+ */
+u64 nfp_resource_size(struct nfp_resource *res)
+{
+	return res->size;
+}