/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
 */
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/sysctl.h>
#include <linux/string.h>
#include <linux/socket.h>
#include <linux/errno.h>
#include <linux/fcntl.h>
#include <linux/in.h>
#include <linux/if_ether.h>	/* For the statistics structure. */
#include <linux/slab.h>
#include <linux/uaccess.h>

#include <asm/io.h>

#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>

#include <net/ip.h>
#include <net/arp.h>

#include <net/ax25.h>
#include <net/netrom.h>

/*
 *	Only allow IP over NET/ROM frames through if the netrom device is up.
 */

int nr_rx_ip(struct sk_buff *skb, struct net_device *dev)
{
	struct net_device_stats *stats = &dev->stats;

	if (!netif_running(dev)) {
		stats->rx_dropped++;
		return 0;
	}

	stats->rx_packets++;
	stats->rx_bytes += skb->len;

	skb->protocol = htons(ETH_P_IP);

	/* Spoof incoming device */
	skb->dev      = dev;
	skb->mac_header = skb->network_header;
	skb_reset_network_header(skb);
	skb->pkt_type = PACKET_HOST;

	netif_rx(skb);

	return 1;
}

static int nr_header(struct sk_buff *skb, struct net_device *dev,
		     unsigned short type,
		     const void *daddr, const void *saddr, unsigned int len)
{
	unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);

	memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len);
	buff[6] &= ~AX25_CBIT;
	buff[6] &= ~AX25_EBIT;
	buff[6] |= AX25_SSSID_SPARE;
	buff    += AX25_ADDR_LEN;

	if (daddr != NULL)
		memcpy(buff, daddr, dev->addr_len);
	buff[6] &= ~AX25_CBIT;
	buff[6] |= AX25_EBIT;
	buff[6] |= AX25_SSSID_SPARE;
	buff    += AX25_ADDR_LEN;

	*buff++ = sysctl_netrom_network_ttl_initialiser;

	*buff++ = NR_PROTO_IP;
	*buff++ = NR_PROTO_IP;
	*buff++ = 0;
	*buff++ = 0;
	*buff++ = NR_PROTOEXT;

	if (daddr != NULL)
		return 37;

	return -37;
}

static int __must_check nr_set_mac_address(struct net_device *dev, void *addr)
{
	struct sockaddr *sa = addr;
	int err;

	if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
		return 0;

	if (dev->flags & IFF_UP) {
		err = ax25_listen_register((ax25_address *)sa->sa_data, NULL);
		if (err)
			return err;

		ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
	}

	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);

	return 0;
}

static int nr_open(struct net_device *dev)
{
	int err;

	err = ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
	if (err)
		return err;

	netif_start_queue(dev);

	return 0;
}

static int nr_close(struct net_device *dev)
{
	ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
	netif_stop_queue(dev);
	return 0;
}

static netdev_tx_t nr_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct net_device_stats *stats = &dev->stats;
	unsigned int len = skb->len;

	if (!nr_route_frame(skb, NULL)) {
		kfree_skb(skb);
		stats->tx_errors++;
		return NETDEV_TX_OK;
	}

	stats->tx_packets++;
	stats->tx_bytes += len;

	return NETDEV_TX_OK;
}

static const struct header_ops nr_header_ops = {
	.create	= nr_header,
};

static const struct net_device_ops nr_netdev_ops = {
	.ndo_open		= nr_open,
	.ndo_stop		= nr_close,
	.ndo_start_xmit		= nr_xmit,
	.ndo_set_mac_address    = nr_set_mac_address,
};

void nr_setup(struct net_device *dev)
{
	dev->mtu		= NR_MAX_PACKET_SIZE;
	dev->netdev_ops		= &nr_netdev_ops;
	dev->header_ops		= &nr_header_ops;
	dev->hard_header_len	= NR_NETWORK_LEN + NR_TRANSPORT_LEN;
	dev->addr_len		= AX25_ADDR_LEN;
	dev->type		= ARPHRD_NETROM;

	/* New-style flags. */
	dev->flags		= IFF_NOARP;
}
eas Herrmann &lt;aherrmann@suse.com&gt;</td><td class='right'>2016-07-22 17:14:11 +0200</td></tr>
<tr><th>committer</th><td>Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;</td><td class='right'>2016-07-22 23:51:06 +0200</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=da7d3abe1c9e5ebac2cf86f97e9e89888a5e2094'>da7d3abe1c9e5ebac2cf86f97e9e89888a5e2094</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=da7d3abe1c9e5ebac2cf86f97e9e89888a5e2094'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=da7d3abe1c9e5ebac2cf86f97e9e89888a5e2094'>6eb238c4de38b21cf594ed3f2a18ce11fd70a2e2</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=ae2c1ca686d4b80258a442fa7f3edc71fd0ebb39'>ae2c1ca686d4b80258a442fa7f3edc71fd0ebb39</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=da7d3abe1c9e5ebac2cf86f97e9e89888a5e2094&amp;id2=ae2c1ca686d4b80258a442fa7f3edc71fd0ebb39'>diff</a>)</td></tr></table>
<div class='commit-subject'>Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency"</div><div class='commit-msg'>This reverts commit 790d849bf811a8ab5d4cd2cce0f6fda92f6aebf2.

Using a v4.7-rc7 kernel on a HP ProLiant triggered following messages

 pcc-cpufreq: (v1.10.00) driver loaded with frequency limits: 1200 MHz, 2800 MHz
 cpufreq: ondemand governor failed, too long transition latency of HW, fallback to performance governor

The last line was shown for each CPU in the system.
Testing v4.5 (where commit 790d849b was integrated) triggered
similar messages. Same behaviour on a 2nd HP Proliant system.

So commit 790d849bf (cpufreq: pcc-cpufreq: update default value of
cpuinfo_transition_latency) causes the system to use performance
governor which, I guess, was not the intention of the patch.

Enabling debug output in pcc-cpufreq provides following verbose output:

 pcc-cpufreq: (v1.10.00) driver loaded with frequency limits: 1200 MHz, 2800 MHz
 pcc_get_offset: for CPU 0: pcc_cpu_data input_offset: 0x44, pcc_cpu_data output_offset: 0x48
 init: policy-&gt;max is 2800000, policy-&gt;min is 1200000
 get: get_freq for CPU 0
 get: SUCCESS: (virtual) output_offset for cpu 0 is 0xffffc9000d7c0048, contains a value of: 0xff06. Speed is: 168000 MHz
 cpufreq: ondemand governor failed, too long transition latency of HW, fallback to performance governor
 target: CPU 0 should go to target freq: 2800000 (virtual) input_offset is 0xffffc9000d7c0044
 target: was SUCCESSFUL for cpu 0

I am asking to revert 790d849bf to re-enable usage of ondemand
governor with pcc-cpufreq.

Fixes: 790d849bf (cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency)
CC: &lt;stable@vger.kernel.org&gt; # 4.5+
Signed-off-by: Andreas Herrmann &lt;aherrmann@suse.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=da7d3abe1c9e5ebac2cf86f97e9e89888a5e2094'>Diffstat</a></div><table summary='diffstat' class='diffstat'>