layerscape: reverse changes to ndo_get_stats64

The NXP LSDK kernel backported changes for interface ndo_get_stats64
functions from mainline, this causes a compile error with
backports/mac80211, which expects the original 4.9 defintion.

As reversing the ndo_get_stats64 change signifcantly reduces the size of
patch 601, the patches that were aggregated into it have been
disaggregated.

Signed-off-by: Mathew McBride <matt@traverse.com.au>

target/linux/layerscape/patches-4.9/001-net-centralize-net_device-min-max-MTU-checking.patch

@@ -0,0 +1,78 @@
+From 95b8bbff6ecf0692747622af16d917a67313f8cc Mon Sep 17 00:00:00 2001
+From: Jarod Wilson <jarod@redhat.com>
+Date: Fri, 7 Oct 2016 22:04:33 -0400
+Subject: [PATCH] net: centralize net_device min/max MTU checking
+
+While looking into an MTU issue with sfc, I started noticing that almost
+every NIC driver with an ndo_change_mtu function implemented almost
+exactly the same range checks, and in many cases, that was the only
+practical thing their ndo_change_mtu function was doing. Quite a few
+drivers have either 68, 64, 60 or 46 as their minimum MTU value checked,
+and then various sizes from 1500 to 65535 for their maximum MTU value. We
+can remove a whole lot of redundant code here if we simple store min_mtu
+and max_mtu in net_device, and check against those in net/core/dev.c's
+dev_set_mtu().
+
+In theory, there should be zero functional change with this patch, it just
+puts the infrastructure in place. Subsequent patches will attempt to start
+using said infrastructure, with theoretically zero change in
+functionality.
+
+CC: netdev@vger.kernel.org
+Signed-off-by: Jarod Wilson <jarod@redhat.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ include/linux/netdevice.h |  4 ++++
+ net/core/dev.c            | 13 +++++++++++--
+ 2 files changed, 15 insertions(+), 2 deletions(-)
+
+diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
+index 780e7171f548..2082b7d02a77 100644
+--- a/include/linux/netdevice.h
++++ b/include/linux/netdevice.h
+@@ -1507,6 +1507,8 @@ enum netdev_priv_flags {
+  *	@if_port:	Selectable AUI, TP, ...
+  *	@dma:		DMA channel
+  *	@mtu:		Interface MTU value
++ *	@min_mtu:	Interface Minimum MTU value
++ *	@max_mtu:	Interface Maximum MTU value
+  *	@type:		Interface hardware type
+  *	@hard_header_len: Maximum hardware header length.
+  *	@min_header_len:  Minimum hardware header length
+@@ -1728,6 +1730,8 @@ struct net_device {
+ 	unsigned char		dma;
+ 
+ 	unsigned int		mtu;
++	unsigned int		min_mtu;
++	unsigned int		max_mtu;
+ 	unsigned short		type;
+ 	unsigned short		hard_header_len;
+ 	unsigned short		min_header_len;
+diff --git a/net/core/dev.c b/net/core/dev.c
+index 2e04fd188081..c7ec56e8659a 100644
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -6524,9 +6524,18 @@ int dev_set_mtu(struct net_device *dev, int new_mtu)
+ 	if (new_mtu == dev->mtu)
+ 		return 0;
+ 
+-	/*	MTU must be positive.	 */
+-	if (new_mtu < 0)
++	/* MTU must be positive, and in range */
++	if (new_mtu < 0 || new_mtu < dev->min_mtu) {
++		net_err_ratelimited("%s: Invalid MTU %d requested, hw min %d\n",
++				    dev->name, new_mtu, dev->min_mtu);
+ 		return -EINVAL;
++	}
++
++	if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
++		net_err_ratelimited("%s: Invalid MTU %d requested, hw max %d\n",
++				    dev->name, new_mtu, dev->min_mtu);
++		return -EINVAL;
++	}
+ 
+ 	if (!netif_device_present(dev))
+ 		return -ENODEV;
+-- 
+2.11.1
+

target/linux/layerscape/patches-4.9/303-add-devm_alloc_percpu-support.patch

@@ -0,0 +1,125 @@
+From d33bde3c487c722541ad359e1d22090a78df0c77 Mon Sep 17 00:00:00 2001
+From: Zhao Qiang <qiang.zhao@nxp.com>
+Date: Tue, 11 Jul 2017 16:47:18 +0800
+Subject: [PATCH] add devm_alloc_percpu support
+
+Signed-off-by: Zhao Qiang <qiang.zhao@nxp.com>
+---
+ drivers/base/devres.c  | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++
+ include/linux/device.h | 19 +++++++++++++++
+ 2 files changed, 85 insertions(+)
+
+diff --git a/drivers/base/devres.c b/drivers/base/devres.c
+index 8fc654f0807b..71d577025285 100644
+--- a/drivers/base/devres.c
++++ b/drivers/base/devres.c
+@@ -10,6 +10,7 @@
+ #include <linux/device.h>
+ #include <linux/module.h>
+ #include <linux/slab.h>
++#include <linux/percpu.h>
+ 
+ #include "base.h"
+ 
+@@ -985,3 +986,68 @@ void devm_free_pages(struct device *dev, unsigned long addr)
+ 			       &devres));
+ }
+ EXPORT_SYMBOL_GPL(devm_free_pages);
++
++static void devm_percpu_release(struct device *dev, void *pdata)
++{
++	void __percpu *p;
++
++	p = *(void __percpu **)pdata;
++	free_percpu(p);
++}
++
++static int devm_percpu_match(struct device *dev, void *data, void *p)
++{
++	struct devres *devr = container_of(data, struct devres, data);
++
++	return *(void **)devr->data == p;
++}
++
++/**
++ * __devm_alloc_percpu - Resource-managed alloc_percpu
++ * @dev: Device to allocate per-cpu memory for
++ * @size: Size of per-cpu memory to allocate
++ * @align: Alignment of per-cpu memory to allocate
++ *
++ * Managed alloc_percpu. Per-cpu memory allocated with this function is
++ * automatically freed on driver detach.
++ *
++ * RETURNS:
++ * Pointer to allocated memory on success, NULL on failure.
++ */
++void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
++		size_t align)
++{
++	void *p;
++	void __percpu *pcpu;
++
++	pcpu = __alloc_percpu(size, align);
++	if (!pcpu)
++		return NULL;
++
++	p = devres_alloc(devm_percpu_release, sizeof(void *), GFP_KERNEL);
++	if (!p) {
++		free_percpu(pcpu);
++		return NULL;
++	}
++
++	*(void __percpu **)p = pcpu;
++
++	devres_add(dev, p);
++
++	return pcpu;
++}
++EXPORT_SYMBOL_GPL(__devm_alloc_percpu);
++
++/**
++ * devm_free_percpu - Resource-managed free_percpu
++ * @dev: Device this memory belongs to
++ * @pdata: Per-cpu memory to free
++ *
++ * Free memory allocated with devm_alloc_percpu().
++ */
++void devm_free_percpu(struct device *dev, void __percpu *pdata)
++{
++	WARN_ON(devres_destroy(dev, devm_percpu_release, devm_percpu_match,
++			       (void *)pdata));
++}
++EXPORT_SYMBOL_GPL(devm_free_percpu);
+diff --git a/include/linux/device.h b/include/linux/device.h
+index bc41e87a969b..0a2135cbddc9 100644
+--- a/include/linux/device.h
++++ b/include/linux/device.h
+@@ -686,6 +686,25 @@ void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
+ int devm_add_action(struct device *dev, void (*action)(void *), void *data);
+ void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
+ 
++/**
++ * devm_alloc_percpu - Resource-managed alloc_percpu
++ * @dev: Device to allocate per-cpu memory for
++ * @type: Type to allocate per-cpu memory for
++ *
++ * Managed alloc_percpu. Per-cpu memory allocated with this function is
++ * automatically freed on driver detach.
++ *
++ * RETURNS:
++ * Pointer to allocated memory on success, NULL on failure.
++ */
++#define devm_alloc_percpu(dev, type)      \
++	((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
++						      __alignof__(type)))
++
++void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
++				   size_t align);
++void devm_free_percpu(struct device *dev, void __percpu *pdata);
++
+ static inline int devm_add_action_or_reset(struct device *dev,
+ 					   void (*action)(void *), void *data)
+ {
+-- 
+2.11.1
+

target/linux/layerscape/patches-4.9/601-net-readd-skb_recycle.patch

@@ -0,0 +1,66 @@
+From 9527ee5eb436ad773acc7320b372a5f4825a920d Mon Sep 17 00:00:00 2001
+From: Madalin Bucur <madalin.bucur@freescale.com>
+Date: Tue, 5 Jan 2016 12:12:07 +0200
+Subject: [PATCH] net: readd skb_recycle()
+
+Adding back skb_recycle() as it's used by the DPAA Ethernet driver.
+This was removed from the upstream kernel because it was lacking users.
+
+Signed-off-by: Madalin Bucur <madalin.bucur@freescale.com>
+---
+ include/linux/skbuff.h |  1 +
+ net/core/skbuff.c      | 26 ++++++++++++++++++++++++++
+ 2 files changed, 27 insertions(+)
+
+diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
+index 32810f279f8e..a52a6fb0ac2e 100644
+--- a/include/linux/skbuff.h
++++ b/include/linux/skbuff.h
+@@ -902,6 +902,7 @@ void kfree_skb(struct sk_buff *skb);
+ void kfree_skb_list(struct sk_buff *segs);
+ void skb_tx_error(struct sk_buff *skb);
+ void consume_skb(struct sk_buff *skb);
++void skb_recycle(struct sk_buff *skb);
+ void  __kfree_skb(struct sk_buff *skb);
+ extern struct kmem_cache *skbuff_head_cache;
+ 
+diff --git a/net/core/skbuff.c b/net/core/skbuff.c
+index fe008f1bd930..ab1038083df2 100644
+--- a/net/core/skbuff.c
++++ b/net/core/skbuff.c
+@@ -825,6 +825,32 @@ void napi_consume_skb(struct sk_buff *skb, int budget)
+ }
+ EXPORT_SYMBOL(napi_consume_skb);
+ 
++/**
++ * 	skb_recycle - clean up an skb for reuse
++ * 	@skb: buffer
++ *
++ * 	Recycles the skb to be reused as a receive buffer. This
++ * 	function does any necessary reference count dropping, and
++ * 	cleans up the skbuff as if it just came from __alloc_skb().
++ */
++void skb_recycle(struct sk_buff *skb)
++{
++	struct skb_shared_info *shinfo;
++	u8 head_frag = skb->head_frag;
++
++	skb_release_head_state(skb);
++
++	shinfo = skb_shinfo(skb);
++	memset(shinfo, 0, offsetof(struct skb_shared_info, dataref));
++	atomic_set(&shinfo->dataref, 1);
++
++	memset(skb, 0, offsetof(struct sk_buff, tail));
++	skb->data = skb->head + NET_SKB_PAD;
++	skb->head_frag = head_frag;
++	skb_reset_tail_pointer(skb);
++}
++EXPORT_SYMBOL(skb_recycle);
++
+ /* Make sure a field is enclosed inside headers_start/headers_end section */
+ #define CHECK_SKB_FIELD(field) \
+ 	BUILD_BUG_ON(offsetof(struct sk_buff, field) <		\
+-- 
+2.11.1
+

target/linux/layerscape/patches-4.9/602-linux-core-export-copy_skb_header-function.patch

@@ -0,0 +1,47 @@
+From eae03a91605fd7dccb1de11053efee87db398df3 Mon Sep 17 00:00:00 2001
+From: Zhang Ying-22455 <ying.zhang22455@nxp.com>
+Date: Fri, 1 Sep 2017 14:56:01 +0800
+Subject: [PATCH] linux/core: export copy_skb_header() function
+
+Signed-off-by: Camelia Groza camelia.groza@nxp.com
+---
+ include/linux/skbuff.h | 1 +
+ net/core/skbuff.c      | 3 ++-
+ 2 files changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
+index a52a6fb0ac2e..a0385f9bdd4e 100644
+--- a/include/linux/skbuff.h
++++ b/include/linux/skbuff.h
+@@ -3063,6 +3063,7 @@ static inline void skb_free_datagram_locked(struct sock *sk,
+ }
+ int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags);
+ int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len);
++void copy_skb_header(struct sk_buff *new, const struct sk_buff *old);
+ int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len);
+ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to,
+ 			      int len, __wsum csum);
+diff --git a/net/core/skbuff.c b/net/core/skbuff.c
+index ab1038083df2..2684c49b9805 100644
+--- a/net/core/skbuff.c
++++ b/net/core/skbuff.c
+@@ -1082,7 +1082,7 @@ static void skb_headers_offset_update(struct sk_buff *skb, int off)
+ 	skb->inner_mac_header += off;
+ }
+ 
+-static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
++void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
+ {
+ 	__copy_skb_header(new, old);
+ 
+@@ -1090,6 +1090,7 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
+ 	skb_shinfo(new)->gso_segs = skb_shinfo(old)->gso_segs;
+ 	skb_shinfo(new)->gso_type = skb_shinfo(old)->gso_type;
+ }
++EXPORT_SYMBOL(copy_skb_header);
+ 
+ static inline int skb_alloc_rx_flag(const struct sk_buff *skb)
+ {
+-- 
+2.11.1
+

target/linux/layerscape/patches-4.9/603-sdk_dpaa-update-the-xmit-timestamp-to-avoid-watchdog.patch

@@ -0,0 +1,60 @@
+From 3d33284eb087deb7f62639a2d2c03b9d0a3eeb34 Mon Sep 17 00:00:00 2001
+From: Camelia Groza <camelia.groza@nxp.com>
+Date: Mon, 11 Sep 2017 17:20:41 +0800
+Subject: [PATCH] sdk_dpaa: update the xmit timestamp to avoid watchdog
+ timeouts
+
+[core-linux part]
+
+Update txq0's trans_start in order to prevent the netdev watchdog from
+triggering too quickly. Since we set the LLTX flag, the stack won't update
+the jiffies for other tx queues. Prevent the watchdog from checking the
+other tx queues by adding the NETIF_HW_ACCEL_MQ flag.
+
+Signed-off-by: Camelia Groza <camelia.groza@nxp.com>
+---
+ include/linux/netdev_features.h | 2 ++
+ net/sched/sch_generic.c         | 7 +++++++
+ 2 files changed, 9 insertions(+)
+
+diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
+index 9c6c8ef2e9e7..90b4107ebeff 100644
+--- a/include/linux/netdev_features.h
++++ b/include/linux/netdev_features.h
+@@ -74,6 +74,7 @@ enum {
+ 	NETIF_F_BUSY_POLL_BIT,		/* Busy poll */
+ 
+ 	NETIF_F_HW_TC_BIT,		/* Offload TC infrastructure */
++	NETIF_F_HW_ACCEL_MQ_BIT,	/* Hardware-accelerated multiqueue */
+ 
+ 	/*
+ 	 * Add your fresh new feature above and remember to update
+@@ -136,6 +137,7 @@ enum {
+ #define NETIF_F_HW_L2FW_DOFFLOAD	__NETIF_F(HW_L2FW_DOFFLOAD)
+ #define NETIF_F_BUSY_POLL	__NETIF_F(BUSY_POLL)
+ #define NETIF_F_HW_TC		__NETIF_F(HW_TC)
++#define NETIF_F_HW_ACCEL_MQ	__NETIF_F(HW_ACCEL_MQ)
+ 
+ #define for_each_netdev_feature(mask_addr, bit)	\
+ 	for_each_set_bit(bit, (unsigned long *)mask_addr, NETDEV_FEATURE_COUNT)
+diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
+index 6cfb6e9038c2..3fab16cb7c58 100644
+--- a/net/sched/sch_generic.c
++++ b/net/sched/sch_generic.c
+@@ -309,6 +309,13 @@ static void dev_watchdog(unsigned long arg)
+ 					txq->trans_timeout++;
+ 					break;
+ 				}
++
++				/* Devices with HW_ACCEL_MQ have multiple txqs
++				 * but update only the first one's transmission
++				 * timestamp so avoid checking the rest.
++				 */
++				if (dev->features & NETIF_F_HW_ACCEL_MQ)
++					break;
+ 			}
+ 
+ 			if (some_queue_timedout) {
+-- 
+2.11.1
+

target/linux/layerscape/patches-4.9/706-fsl-dpaa-use-4-9-ndo-get-stats64.patch

@@ -0,0 +1,112 @@
+From: Mathew McBride <matt@traverse.com.au>
+Date: Tue, 24 Oct 2017 11:30:00 +1100
+Subject: [PATCH] dpaa: backport use of 4.9 ndo_get_stats64
+
+This patch changes the declarations of ndo_get_stats64 handlers
+to the previous struct rtnl_link_stats64 * return type instead of
+the mainline void return.
+
+Suggested-by: Adrien Gallouët <adrien@gallouet.fr>
+Signed-off-by: Mathew McBride <matt@traverse.com.au>
+
+---
+ drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_common.c |    5 +++--
+ drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_common.h |    4 ++--
+ drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c            |    3 ++-
+ drivers/staging/fsl-dpaa2/ethsw/switch.c                  |    4 ++--
+ drivers/staging/fsl-dpaa2/evb/evb.c                       |    4 ++--
+ 5 files changed, 11 insertions(+), 9 deletions(-)
+
+--- a/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c
++++ b/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c
+@@ -1296,7 +1296,7 @@ static int dpaa2_eth_set_addr(struct net
+ /** Fill in counters maintained by the GPP driver. These may be different from
+  * the hardware counters obtained by ethtool.
+  */
+-static void dpaa2_eth_get_stats(struct net_device *net_dev,
++static struct rtnl_link_stats64 *dpaa2_eth_get_stats(struct net_device *net_dev,
+ 				struct rtnl_link_stats64 *stats)
+ {
+ 	struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
+@@ -1312,6 +1312,7 @@ static void dpaa2_eth_get_stats(struct n
+ 		for (j = 0; j < num; j++)
+ 			netstats[j] += cpustats[j];
+ 	}
++	return stats;
+ }
+ 
+ static int dpaa2_eth_change_mtu(struct net_device *net_dev, int mtu)
+--- a/drivers/staging/fsl-dpaa2/ethsw/switch.c
++++ b/drivers/staging/fsl-dpaa2/ethsw/switch.c
+@@ -1094,7 +1094,7 @@ static int ethsw_port_fdb_del(struct ndm
+ 	return 0;
+ }
+ 
+-void ethsw_port_get_stats(struct net_device *netdev,
++struct rtnl_link_stats64 *ethsw_port_get_stats(struct net_device *netdev,
+ 			  struct rtnl_link_stats64 *storage)
+ {
+ 	struct ethsw_port_priv	*port_priv = netdev_priv(netdev);
+@@ -1154,7 +1154,7 @@ void ethsw_port_get_stats(struct net_dev
+ 	if (err)
+ 		goto error;
+ 
+-	return;
++	return storage;
+ 
+ error:
+ 	netdev_err(netdev, "dpsw_if_get_counter err %d\n", err);
+--- a/drivers/staging/fsl-dpaa2/evb/evb.c
++++ b/drivers/staging/fsl-dpaa2/evb/evb.c
+@@ -765,7 +765,7 @@ static int evb_dellink(struct net_device
+ 	return 0;
+ }
+ 
+-void evb_port_get_stats(struct net_device *netdev,
++struct rtnl_link_stats64 *evb_port_get_stats(struct net_device *netdev,
+ 			struct rtnl_link_stats64 *storage)
+ {
+ 	struct evb_port_priv	*port_priv = netdev_priv(netdev);
+@@ -842,7 +842,7 @@ void evb_port_get_stats(struct net_devic
+ 	if (unlikely(err))
+ 		goto error;
+ 
+-	return;
++	return storage;
+ 
+ error:
+ 	netdev_err(netdev, "dpdmux_if_get_counter err %d\n", err);
+--- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_common.c
++++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_common.c
+@@ -239,8 +239,8 @@ EXPORT_SYMBOL(dpa_timeout);
+  * Calculates the statistics for the given device by adding the statistics
+  * collected by each CPU.
+  */
+-void __cold
+-dpa_get_stats64(struct net_device *net_dev,
++struct rtnl_link_stats64 __cold
++*dpa_get_stats64(struct net_device *net_dev,
+ 		struct rtnl_link_stats64 *stats)
+ {
+ 	struct dpa_priv_s *priv = netdev_priv(net_dev);
+@@ -258,6 +258,7 @@ dpa_get_stats64(struct net_device *net_d
+ 		for (j = 0; j < numstats; j++)
+ 			netstats[j] += cpustats[j];
+ 	}
++	return stats;
+ }
+ EXPORT_SYMBOL(dpa_get_stats64);
+ 
+--- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_common.h
++++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_common.h
+@@ -140,8 +140,8 @@ int dpa_netdev_init(struct net_device *n
+ int __cold dpa_start(struct net_device *net_dev);
+ int __cold dpa_stop(struct net_device *net_dev);
+ void __cold dpa_timeout(struct net_device *net_dev);
+-void __cold
+-dpa_get_stats64(struct net_device *net_dev,
++struct rtnl_link_stats64 __cold
++*dpa_get_stats64(struct net_device *net_dev,
+ 		struct rtnl_link_stats64 *stats);
+ int dpa_change_mtu(struct net_device *net_dev, int new_mtu);
+ int dpa_ndo_init(struct net_device *net_dev);

target/linux/layerscape/patches-4.9/820-base-soc-Introduce-soc_device_match-interface.patch

@@ -0,0 +1,162 @@
+From c97db7cc7778e34a53b42d58c766f0ec0e30d580 Mon Sep 17 00:00:00 2001
+From: Arnd Bergmann <arnd@arndb.de>
+Date: Wed, 21 Sep 2016 14:57:19 +0800
+Subject: [PATCH] base: soc: Introduce soc_device_match() interface
+
+We keep running into cases where device drivers want to know the exact
+version of the a SoC they are currently running on. In the past, this has
+usually been done through a vendor specific API that can be called by a
+driver, or by directly accessing some kind of version register that is
+not part of the device itself but that belongs to a global register area
+of the chip.
+
+Common reasons for doing this include:
+
+- A machine is not using devicetree or similar for passing data about
+  on-chip devices, but just announces their presence using boot-time
+  platform devices, and the machine code itself does not care about the
+  revision.
+
+- There is existing firmware or boot loaders with existing DT binaries
+  with generic compatible strings that do not identify the particular
+  revision of each device, but the driver knows which SoC revisions
+  include which part.
+
+- A prerelease version of a chip has some quirks and we are using the same
+  version of the bootloader and the DT blob on both the prerelease and the
+  final version. An update of the DT binding seems inappropriate because
+  that would involve maintaining multiple copies of the dts and/or
+  bootloader.
+
+This patch introduces the soc_device_match() interface that is meant to
+work like of_match_node() but instead of identifying the version of a
+device, it identifies the SoC itself using a vendor-agnostic interface.
+
+Unlike of_match_node(), we do not do an exact string compare but instead
+use glob_match() to allow wildcards in strings.
+
+Signed-off-by: Arnd Bergmann <arnd@arndb.de>
+Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
+Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
+Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/base/Kconfig    |  1 +
+ drivers/base/soc.c      | 66 +++++++++++++++++++++++++++++++++++++++++++++++++
+ include/linux/sys_soc.h |  3 +++
+ 3 files changed, 70 insertions(+)
+
+diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
+index fdf44cac08e6..991b21e1f89b 100644
+--- a/drivers/base/Kconfig
++++ b/drivers/base/Kconfig
+@@ -235,6 +235,7 @@ config GENERIC_CPU_AUTOPROBE
+ 
+ config SOC_BUS
+ 	bool
++	select GLOB
+ 
+ source "drivers/base/regmap/Kconfig"
+ 
+diff --git a/drivers/base/soc.c b/drivers/base/soc.c
+index 028cef377fd4..04ee597fc3a3 100644
+--- a/drivers/base/soc.c
++++ b/drivers/base/soc.c
+@@ -13,6 +13,7 @@
+ #include <linux/spinlock.h>
+ #include <linux/sys_soc.h>
+ #include <linux/err.h>
++#include <linux/glob.h>
+ 
+ static DEFINE_IDA(soc_ida);
+ 
+@@ -168,3 +169,68 @@ static int __init soc_bus_register(void)
+ 	return bus_register(&soc_bus_type);
+ }
+ core_initcall(soc_bus_register);
++
++static int soc_device_match_one(struct device *dev, void *arg)
++{
++	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev);
++	const struct soc_device_attribute *match = arg;
++
++	if (match->machine &&
++	    !glob_match(match->machine, soc_dev->attr->machine))
++		return 0;
++
++	if (match->family &&
++	    !glob_match(match->family, soc_dev->attr->family))
++		return 0;
++
++	if (match->revision &&
++	    !glob_match(match->revision, soc_dev->attr->revision))
++		return 0;
++
++	if (match->soc_id &&
++	    !glob_match(match->soc_id, soc_dev->attr->soc_id))
++		return 0;
++
++	return 1;
++}
++
++/*
++ * soc_device_match - identify the SoC in the machine
++ * @matches: zero-terminated array of possible matches
++ *
++ * returns the first matching entry of the argument array, or NULL
++ * if none of them match.
++ *
++ * This function is meant as a helper in place of of_match_node()
++ * in cases where either no device tree is available or the information
++ * in a device node is insufficient to identify a particular variant
++ * by its compatible strings or other properties. For new devices,
++ * the DT binding should always provide unique compatible strings
++ * that allow the use of of_match_node() instead.
++ *
++ * The calling function can use the .data entry of the
++ * soc_device_attribute to pass a structure or function pointer for
++ * each entry.
++ */
++const struct soc_device_attribute *soc_device_match(
++	const struct soc_device_attribute *matches)
++{
++	int ret = 0;
++
++	if (!matches)
++		return NULL;
++
++	while (!ret) {
++		if (!(matches->machine || matches->family ||
++		      matches->revision || matches->soc_id))
++			break;
++		ret = bus_for_each_dev(&soc_bus_type, NULL, (void *)matches,
++				       soc_device_match_one);
++		if (!ret)
++			matches++;
++		else
++			return matches;
++	}
++	return NULL;
++}
++EXPORT_SYMBOL_GPL(soc_device_match);
+diff --git a/include/linux/sys_soc.h b/include/linux/sys_soc.h
+index 2739ccb69571..9f5eb06f9fd8 100644
+--- a/include/linux/sys_soc.h
++++ b/include/linux/sys_soc.h
+@@ -13,6 +13,7 @@ struct soc_device_attribute {
+ 	const char *family;
+ 	const char *revision;
+ 	const char *soc_id;
++	const void *data;
+ };
+ 
+ /**
+@@ -34,4 +35,6 @@ void soc_device_unregister(struct soc_device *soc_dev);
+  */
+ struct device *soc_device_to_device(struct soc_device *soc);
+ 
++const struct soc_device_attribute *soc_device_match(
++	const struct soc_device_attribute *matches);
+ #endif /* __SOC_BUS_H */
+-- 
+2.11.1
+