linux/drivers/net/dsa/bcm_sf2.h
Florian Fainelli 4f101c4779 net: dsa: bcm_sf2: Fix race condition while unmasking interrupts
We kept shadow copies of which interrupt sources we have enabled and
disabled, but due to an order bug in how intrl2_mask_clear was defined,
we could run into the following scenario:

CPU0					CPU1
intrl2_1_mask_clear(..)
sets INTRL2_CPU_MASK_CLEAR
					bcm_sf2_switch_1_isr
					read INTRL2_CPU_STATUS and masks with stale
					irq1_mask value
updates irq1_mask value

Which would make us loop again and again trying to process and interrupt
we are not clearing since our copy of whether it was enabled before
still indicates it was not. Fix this by updating the shadow copy first,
and then unasking at the HW level.

Fixes: 246d7f773c ("net: dsa: add Broadcom SF2 switch driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-25 16:49:25 -07:00

230 lines
5.4 KiB
C

/*
* Broadcom Starfighter2 private context
*
* Copyright (C) 2014, Broadcom Corporation
*
* 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.
*/
#ifndef __BCM_SF2_H
#define __BCM_SF2_H
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/types.h>
#include <linux/bitops.h>
#include <linux/if_vlan.h>
#include <net/dsa.h>
#include "bcm_sf2_regs.h"
struct bcm_sf2_hw_params {
u16 top_rev;
u16 core_rev;
u16 gphy_rev;
u32 num_gphy;
u8 num_acb_queue;
u8 num_rgmii;
u8 num_ports;
u8 fcb_pause_override:1;
u8 acb_packets_inflight:1;
};
#define BCM_SF2_REGS_NAME {\
"core", "reg", "intrl2_0", "intrl2_1", "fcb", "acb" \
}
#define BCM_SF2_REGS_NUM 6
struct bcm_sf2_port_status {
unsigned int link;
struct ethtool_eee eee;
u32 vlan_ctl_mask;
u16 pvid;
struct net_device *bridge_dev;
};
struct bcm_sf2_arl_entry {
u8 port;
u8 mac[ETH_ALEN];
u16 vid;
u8 is_valid:1;
u8 is_age:1;
u8 is_static:1;
};
struct bcm_sf2_vlan {
u16 members;
u16 untag;
};
static inline void bcm_sf2_mac_from_u64(u64 src, u8 *dst)
{
unsigned int i;
for (i = 0; i < ETH_ALEN; i++)
dst[ETH_ALEN - 1 - i] = (src >> (8 * i)) & 0xff;
}
static inline u64 bcm_sf2_mac_to_u64(const u8 *src)
{
unsigned int i;
u64 dst = 0;
for (i = 0; i < ETH_ALEN; i++)
dst |= (u64)src[ETH_ALEN - 1 - i] << (8 * i);
return dst;
}
static inline void bcm_sf2_arl_to_entry(struct bcm_sf2_arl_entry *ent,
u64 mac_vid, u32 fwd_entry)
{
memset(ent, 0, sizeof(*ent));
ent->port = fwd_entry & PORTID_MASK;
ent->is_valid = !!(fwd_entry & ARL_VALID);
ent->is_age = !!(fwd_entry & ARL_AGE);
ent->is_static = !!(fwd_entry & ARL_STATIC);
bcm_sf2_mac_from_u64(mac_vid, ent->mac);
ent->vid = mac_vid >> VID_SHIFT;
}
static inline void bcm_sf2_arl_from_entry(u64 *mac_vid, u32 *fwd_entry,
const struct bcm_sf2_arl_entry *ent)
{
*mac_vid = bcm_sf2_mac_to_u64(ent->mac);
*mac_vid |= (u64)(ent->vid & VID_MASK) << VID_SHIFT;
*fwd_entry = ent->port & PORTID_MASK;
if (ent->is_valid)
*fwd_entry |= ARL_VALID;
if (ent->is_static)
*fwd_entry |= ARL_STATIC;
if (ent->is_age)
*fwd_entry |= ARL_AGE;
}
struct bcm_sf2_priv {
/* Base registers, keep those in order with BCM_SF2_REGS_NAME */
void __iomem *core;
void __iomem *reg;
void __iomem *intrl2_0;
void __iomem *intrl2_1;
void __iomem *fcb;
void __iomem *acb;
/* spinlock protecting access to the indirect registers */
spinlock_t indir_lock;
int irq0;
int irq1;
u32 irq0_stat;
u32 irq0_mask;
u32 irq1_stat;
u32 irq1_mask;
/* Mutex protecting access to the MIB counters */
struct mutex stats_mutex;
struct bcm_sf2_hw_params hw_params;
struct bcm_sf2_port_status port_sts[DSA_MAX_PORTS];
/* Mask of ports enabled for Wake-on-LAN */
u32 wol_ports_mask;
/* MoCA port location */
int moca_port;
/* Bitmask of ports having an integrated PHY */
unsigned int int_phy_mask;
/* Master and slave MDIO bus controller */
unsigned int indir_phy_mask;
struct device_node *master_mii_dn;
struct mii_bus *slave_mii_bus;
struct mii_bus *master_mii_bus;
/* Cache of programmed VLANs */
struct bcm_sf2_vlan vlans[VLAN_N_VID];
};
struct bcm_sf2_hw_stats {
const char *string;
u16 reg;
u8 sizeof_stat;
};
#define SF2_IO_MACRO(name) \
static inline u32 name##_readl(struct bcm_sf2_priv *priv, u32 off) \
{ \
return __raw_readl(priv->name + off); \
} \
static inline void name##_writel(struct bcm_sf2_priv *priv, \
u32 val, u32 off) \
{ \
__raw_writel(val, priv->name + off); \
} \
/* Accesses to 64-bits register requires us to latch the hi/lo pairs
* using the REG_DIR_DATA_{READ,WRITE} ancillary registers. The 'indir_lock'
* spinlock is automatically grabbed and released to provide relative
* atomiticy with latched reads/writes.
*/
#define SF2_IO64_MACRO(name) \
static inline u64 name##_readq(struct bcm_sf2_priv *priv, u32 off) \
{ \
u32 indir, dir; \
spin_lock(&priv->indir_lock); \
dir = __raw_readl(priv->name + off); \
indir = reg_readl(priv, REG_DIR_DATA_READ); \
spin_unlock(&priv->indir_lock); \
return (u64)indir << 32 | dir; \
} \
static inline void name##_writeq(struct bcm_sf2_priv *priv, u64 val, \
u32 off) \
{ \
spin_lock(&priv->indir_lock); \
reg_writel(priv, upper_32_bits(val), REG_DIR_DATA_WRITE); \
__raw_writel(lower_32_bits(val), priv->name + off); \
spin_unlock(&priv->indir_lock); \
}
#define SWITCH_INTR_L2(which) \
static inline void intrl2_##which##_mask_clear(struct bcm_sf2_priv *priv, \
u32 mask) \
{ \
priv->irq##which##_mask &= ~(mask); \
intrl2_##which##_writel(priv, mask, INTRL2_CPU_MASK_CLEAR); \
} \
static inline void intrl2_##which##_mask_set(struct bcm_sf2_priv *priv, \
u32 mask) \
{ \
intrl2_## which##_writel(priv, mask, INTRL2_CPU_MASK_SET); \
priv->irq##which##_mask |= (mask); \
} \
SF2_IO_MACRO(core);
SF2_IO_MACRO(reg);
SF2_IO64_MACRO(core);
SF2_IO_MACRO(intrl2_0);
SF2_IO_MACRO(intrl2_1);
SF2_IO_MACRO(fcb);
SF2_IO_MACRO(acb);
SWITCH_INTR_L2(0);
SWITCH_INTR_L2(1);
#endif /* __BCM_SF2_H */