net: ll_temac: Prepare indirect register access for multicast support

With .ndo_set_rx_mode/temac_set_multicast_list() being called in atomic
context (holding addr_list_lock), and temac_set_multicast_list() needing
to access temac indirect registers, the mutex used to synchronize indirect
register is a no-no.

Replace it with a spinlock, and avoid sleeping in
temac_indirect_busywait().

To avoid excessive holding of the lock, which is now a spinlock, the
temac_device_reset() function is changed to only hold the lock for short
periods.  With timeouts, it could be holding the spinlock for more than
2 seconds.

Signed-off-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Esben Haabendal 2019-05-23 14:02:20 +02:00 коммит произвёл David S. Miller
Родитель ddc0bf34f9
Коммит 1bd33bf0fe
4 изменённых файлов: 181 добавлений и 91 удалений

Просмотреть файл

@ -361,7 +361,7 @@ struct temac_local {
/* For synchronization of indirect register access. Must be
* shared mutex between interfaces in same TEMAC block.
*/
struct mutex *indirect_mutex;
spinlock_t *indirect_lock;
u32 options; /* Current options word */
int last_link;
unsigned int temac_features;
@ -388,8 +388,9 @@ struct temac_local {
/* xilinx_temac.c */
int temac_indirect_busywait(struct temac_local *lp);
u32 temac_indirect_in32(struct temac_local *lp, int reg);
u32 temac_indirect_in32_locked(struct temac_local *lp, int reg);
void temac_indirect_out32(struct temac_local *lp, int reg, u32 value);
void temac_indirect_out32_locked(struct temac_local *lp, int reg, u32 value);
/* xilinx_temac_mdio.c */
int temac_mdio_setup(struct temac_local *lp, struct platform_device *pdev);

Просмотреть файл

@ -53,6 +53,7 @@
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/processor.h>
#include <linux/platform_data/xilinx-ll-temac.h>
#include "ll_temac.h"
@ -84,51 +85,118 @@ static void _temac_iow_le(struct temac_local *lp, int offset, u32 value)
return iowrite32(value, lp->regs + offset);
}
static bool hard_acs_rdy(struct temac_local *lp)
{
return temac_ior(lp, XTE_RDY0_OFFSET) & XTE_RDY0_HARD_ACS_RDY_MASK;
}
static bool hard_acs_rdy_or_timeout(struct temac_local *lp, ktime_t timeout)
{
ktime_t cur = ktime_get();
return hard_acs_rdy(lp) || ktime_after(cur, timeout);
}
/* Poll for maximum 20 ms. This is similar to the 2 jiffies @ 100 Hz
* that was used before, and should cover MDIO bus speed down to 3200
* Hz.
*/
#define HARD_ACS_RDY_POLL_NS (20 * NSEC_PER_MSEC)
/**
* temac_indirect_busywait - Wait for current indirect register access
* to complete.
*/
int temac_indirect_busywait(struct temac_local *lp)
{
unsigned long end = jiffies + 2;
ktime_t timeout = ktime_add_ns(ktime_get(), HARD_ACS_RDY_POLL_NS);
while (!(temac_ior(lp, XTE_RDY0_OFFSET) & XTE_RDY0_HARD_ACS_RDY_MASK)) {
if (time_before_eq(end, jiffies)) {
WARN_ON(1);
return -ETIMEDOUT;
}
usleep_range(500, 1000);
}
return 0;
spin_until_cond(hard_acs_rdy_or_timeout(lp, timeout));
if (WARN_ON(!hard_acs_rdy(lp)))
return -ETIMEDOUT;
else
return 0;
}
/**
* temac_indirect_in32
*
* lp->indirect_mutex must be held when calling this function
* temac_indirect_in32 - Indirect register read access. This function
* must be called without lp->indirect_lock being held.
*/
u32 temac_indirect_in32(struct temac_local *lp, int reg)
{
u32 val;
if (temac_indirect_busywait(lp))
return -ETIMEDOUT;
temac_iow(lp, XTE_CTL0_OFFSET, reg);
if (temac_indirect_busywait(lp))
return -ETIMEDOUT;
val = temac_ior(lp, XTE_LSW0_OFFSET);
unsigned long flags;
int val;
spin_lock_irqsave(lp->indirect_lock, flags);
val = temac_indirect_in32_locked(lp, reg);
spin_unlock_irqrestore(lp->indirect_lock, flags);
return val;
}
/**
* temac_indirect_out32
*
* lp->indirect_mutex must be held when calling this function
* temac_indirect_in32_locked - Indirect register read access. This
* function must be called with lp->indirect_lock being held. Use
* this together with spin_lock_irqsave/spin_lock_irqrestore to avoid
* repeated lock/unlock and to ensure uninterrupted access to indirect
* registers.
*/
u32 temac_indirect_in32_locked(struct temac_local *lp, int reg)
{
/* This initial wait should normally not spin, as we always
* try to wait for indirect access to complete before
* releasing the indirect_lock.
*/
if (WARN_ON(temac_indirect_busywait(lp)))
return -ETIMEDOUT;
/* Initiate read from indirect register */
temac_iow(lp, XTE_CTL0_OFFSET, reg);
/* Wait for indirect register access to complete. We really
* should not see timeouts, and could even end up causing
* problem for following indirect access, so let's make a bit
* of WARN noise.
*/
if (WARN_ON(temac_indirect_busywait(lp)))
return -ETIMEDOUT;
/* Value is ready now */
return temac_ior(lp, XTE_LSW0_OFFSET);
}
/**
* temac_indirect_out32 - Indirect register write access. This function
* must be called without lp->indirect_lock being held.
*/
void temac_indirect_out32(struct temac_local *lp, int reg, u32 value)
{
if (temac_indirect_busywait(lp))
unsigned long flags;
spin_lock_irqsave(lp->indirect_lock, flags);
temac_indirect_out32_locked(lp, reg, value);
spin_unlock_irqrestore(lp->indirect_lock, flags);
}
/**
* temac_indirect_out32_locked - Indirect register write access. This
* function must be called with lp->indirect_lock being held. Use
* this together with spin_lock_irqsave/spin_lock_irqrestore to avoid
* repeated lock/unlock and to ensure uninterrupted access to indirect
* registers.
*/
void temac_indirect_out32_locked(struct temac_local *lp, int reg, u32 value)
{
/* As in temac_indirect_in32_locked(), we should normally not
* spin here. And if it happens, we actually end up silently
* ignoring the write request. Ouch.
*/
if (WARN_ON(temac_indirect_busywait(lp)))
return;
/* Initiate write to indirect register */
temac_iow(lp, XTE_LSW0_OFFSET, value);
temac_iow(lp, XTE_CTL0_OFFSET, CNTLREG_WRITE_ENABLE_MASK | reg);
temac_indirect_busywait(lp);
/* As in temac_indirect_in32_locked(), we should not see timeouts
* here. And if it happens, we continue before the write has
* completed. Not good.
*/
WARN_ON(temac_indirect_busywait(lp));
}
/**
@ -344,20 +412,21 @@ out:
static void temac_do_set_mac_address(struct net_device *ndev)
{
struct temac_local *lp = netdev_priv(ndev);
unsigned long flags;
/* set up unicast MAC address filter set its mac address */
mutex_lock(lp->indirect_mutex);
temac_indirect_out32(lp, XTE_UAW0_OFFSET,
(ndev->dev_addr[0]) |
(ndev->dev_addr[1] << 8) |
(ndev->dev_addr[2] << 16) |
(ndev->dev_addr[3] << 24));
spin_lock_irqsave(lp->indirect_lock, flags);
temac_indirect_out32_locked(lp, XTE_UAW0_OFFSET,
(ndev->dev_addr[0]) |
(ndev->dev_addr[1] << 8) |
(ndev->dev_addr[2] << 16) |
(ndev->dev_addr[3] << 24));
/* There are reserved bits in EUAW1
* so don't affect them Set MAC bits [47:32] in EUAW1 */
temac_indirect_out32(lp, XTE_UAW1_OFFSET,
(ndev->dev_addr[4] & 0x000000ff) |
(ndev->dev_addr[5] << 8));
mutex_unlock(lp->indirect_mutex);
temac_indirect_out32_locked(lp, XTE_UAW1_OFFSET,
(ndev->dev_addr[4] & 0x000000ff) |
(ndev->dev_addr[5] << 8));
spin_unlock_irqrestore(lp->indirect_lock, flags);
}
static int temac_init_mac_address(struct net_device *ndev, const void *address)
@ -383,42 +452,56 @@ static int temac_set_mac_address(struct net_device *ndev, void *p)
static void temac_set_multicast_list(struct net_device *ndev)
{
struct temac_local *lp = netdev_priv(ndev);
u32 multi_addr_msw, multi_addr_lsw, val;
u32 multi_addr_msw, multi_addr_lsw;
int i;
unsigned long flags;
bool promisc_mode_disabled = false;
mutex_lock(lp->indirect_mutex);
if (ndev->flags & (IFF_ALLMULTI | IFF_PROMISC) ||
netdev_mc_count(ndev) > MULTICAST_CAM_TABLE_NUM) {
if (ndev->flags & (IFF_PROMISC | IFF_ALLMULTI) ||
(netdev_mc_count(ndev) > MULTICAST_CAM_TABLE_NUM)) {
temac_indirect_out32(lp, XTE_AFM_OFFSET, XTE_AFM_EPPRM_MASK);
dev_info(&ndev->dev, "Promiscuous mode enabled.\n");
} else if (!netdev_mc_empty(ndev)) {
return;
}
spin_lock_irqsave(lp->indirect_lock, flags);
if (!netdev_mc_empty(ndev)) {
struct netdev_hw_addr *ha;
i = 0;
netdev_for_each_mc_addr(ha, ndev) {
if (i >= MULTICAST_CAM_TABLE_NUM)
if (WARN_ON(i >= MULTICAST_CAM_TABLE_NUM))
break;
multi_addr_msw = ((ha->addr[3] << 24) |
(ha->addr[2] << 16) |
(ha->addr[1] << 8) |
(ha->addr[0]));
temac_indirect_out32(lp, XTE_MAW0_OFFSET,
multi_addr_msw);
temac_indirect_out32_locked(lp, XTE_MAW0_OFFSET,
multi_addr_msw);
multi_addr_lsw = ((ha->addr[5] << 8) |
(ha->addr[4]) | (i << 16));
temac_indirect_out32(lp, XTE_MAW1_OFFSET,
multi_addr_lsw);
temac_indirect_out32_locked(lp, XTE_MAW1_OFFSET,
multi_addr_lsw);
i++;
}
} else {
val = temac_indirect_in32(lp, XTE_AFM_OFFSET);
temac_indirect_out32(lp, XTE_AFM_OFFSET,
val & ~XTE_AFM_EPPRM_MASK);
temac_indirect_out32(lp, XTE_MAW0_OFFSET, 0);
temac_indirect_out32(lp, XTE_MAW1_OFFSET, 0);
dev_info(&ndev->dev, "Promiscuous mode disabled.\n");
temac_indirect_out32_locked(lp, XTE_MAW0_OFFSET, 0);
temac_indirect_out32_locked(lp, XTE_MAW1_OFFSET, i << 16);
}
}
mutex_unlock(lp->indirect_mutex);
/* Enable address filter block if currently disabled */
if (temac_indirect_in32_locked(lp, XTE_AFM_OFFSET)
& XTE_AFM_EPPRM_MASK) {
temac_indirect_out32_locked(lp, XTE_AFM_OFFSET, 0);
promisc_mode_disabled = true;
}
spin_unlock_irqrestore(lp->indirect_lock, flags);
if (promisc_mode_disabled)
dev_info(&ndev->dev, "Promiscuous mode disabled.\n");
}
static struct temac_option {
@ -509,17 +592,19 @@ static u32 temac_setoptions(struct net_device *ndev, u32 options)
struct temac_local *lp = netdev_priv(ndev);
struct temac_option *tp = &temac_options[0];
int reg;
unsigned long flags;
mutex_lock(lp->indirect_mutex);
spin_lock_irqsave(lp->indirect_lock, flags);
while (tp->opt) {
reg = temac_indirect_in32(lp, tp->reg) & ~tp->m_or;
if (options & tp->opt)
reg = temac_indirect_in32_locked(lp, tp->reg) & ~tp->m_or;
if (options & tp->opt) {
reg |= tp->m_or;
temac_indirect_out32(lp, tp->reg, reg);
temac_indirect_out32_locked(lp, tp->reg, reg);
}
tp++;
}
spin_unlock_irqrestore(lp->indirect_lock, flags);
lp->options |= options;
mutex_unlock(lp->indirect_mutex);
return 0;
}
@ -530,6 +615,7 @@ static void temac_device_reset(struct net_device *ndev)
struct temac_local *lp = netdev_priv(ndev);
u32 timeout;
u32 val;
unsigned long flags;
/* Perform a software reset */
@ -538,7 +624,6 @@ static void temac_device_reset(struct net_device *ndev)
dev_dbg(&ndev->dev, "%s()\n", __func__);
mutex_lock(lp->indirect_mutex);
/* Reset the receiver and wait for it to finish reset */
temac_indirect_out32(lp, XTE_RXC1_OFFSET, XTE_RXC1_RXRST_MASK);
timeout = 1000;
@ -564,8 +649,11 @@ static void temac_device_reset(struct net_device *ndev)
}
/* Disable the receiver */
val = temac_indirect_in32(lp, XTE_RXC1_OFFSET);
temac_indirect_out32(lp, XTE_RXC1_OFFSET, val & ~XTE_RXC1_RXEN_MASK);
spin_lock_irqsave(lp->indirect_lock, flags);
val = temac_indirect_in32_locked(lp, XTE_RXC1_OFFSET);
temac_indirect_out32_locked(lp, XTE_RXC1_OFFSET,
val & ~XTE_RXC1_RXEN_MASK);
spin_unlock_irqrestore(lp->indirect_lock, flags);
/* Reset Local Link (DMA) */
lp->dma_out(lp, DMA_CONTROL_REG, DMA_CONTROL_RST);
@ -585,12 +673,12 @@ static void temac_device_reset(struct net_device *ndev)
"temac_device_reset descriptor allocation failed\n");
}
temac_indirect_out32(lp, XTE_RXC0_OFFSET, 0);
temac_indirect_out32(lp, XTE_RXC1_OFFSET, 0);
temac_indirect_out32(lp, XTE_TXC_OFFSET, 0);
temac_indirect_out32(lp, XTE_FCC_OFFSET, XTE_FCC_RXFLO_MASK);
mutex_unlock(lp->indirect_mutex);
spin_lock_irqsave(lp->indirect_lock, flags);
temac_indirect_out32_locked(lp, XTE_RXC0_OFFSET, 0);
temac_indirect_out32_locked(lp, XTE_RXC1_OFFSET, 0);
temac_indirect_out32_locked(lp, XTE_TXC_OFFSET, 0);
temac_indirect_out32_locked(lp, XTE_FCC_OFFSET, XTE_FCC_RXFLO_MASK);
spin_unlock_irqrestore(lp->indirect_lock, flags);
/* Sync default options with HW
* but leave receiver and transmitter disabled. */
@ -614,13 +702,14 @@ static void temac_adjust_link(struct net_device *ndev)
struct phy_device *phy = ndev->phydev;
u32 mii_speed;
int link_state;
unsigned long flags;
/* hash together the state values to decide if something has changed */
link_state = phy->speed | (phy->duplex << 1) | phy->link;
mutex_lock(lp->indirect_mutex);
if (lp->last_link != link_state) {
mii_speed = temac_indirect_in32(lp, XTE_EMCFG_OFFSET);
spin_lock_irqsave(lp->indirect_lock, flags);
mii_speed = temac_indirect_in32_locked(lp, XTE_EMCFG_OFFSET);
mii_speed &= ~XTE_EMCFG_LINKSPD_MASK;
switch (phy->speed) {
@ -630,11 +719,12 @@ static void temac_adjust_link(struct net_device *ndev)
}
/* Write new speed setting out to TEMAC */
temac_indirect_out32(lp, XTE_EMCFG_OFFSET, mii_speed);
temac_indirect_out32_locked(lp, XTE_EMCFG_OFFSET, mii_speed);
spin_unlock_irqrestore(lp->indirect_lock, flags);
lp->last_link = link_state;
phy_print_status(phy);
}
mutex_unlock(lp->indirect_mutex);
}
#ifdef CONFIG_64BIT
@ -1096,17 +1186,17 @@ static int temac_probe(struct platform_device *pdev)
/* Setup mutex for synchronization of indirect register access */
if (pdata) {
if (!pdata->indirect_mutex) {
if (!pdata->indirect_lock) {
dev_err(&pdev->dev,
"indirect_mutex missing in platform_data\n");
"indirect_lock missing in platform_data\n");
return -EINVAL;
}
lp->indirect_mutex = pdata->indirect_mutex;
lp->indirect_lock = pdata->indirect_lock;
} else {
lp->indirect_mutex = devm_kmalloc(&pdev->dev,
sizeof(*lp->indirect_mutex),
GFP_KERNEL);
mutex_init(lp->indirect_mutex);
lp->indirect_lock = devm_kmalloc(&pdev->dev,
sizeof(*lp->indirect_lock),
GFP_KERNEL);
spin_lock_init(lp->indirect_lock);
}
/* map device registers */

Просмотреть файл

@ -25,14 +25,15 @@ static int temac_mdio_read(struct mii_bus *bus, int phy_id, int reg)
{
struct temac_local *lp = bus->priv;
u32 rc;
unsigned long flags;
/* Write the PHY address to the MIIM Access Initiator register.
* When the transfer completes, the PHY register value will appear
* in the LSW0 register */
mutex_lock(lp->indirect_mutex);
spin_lock_irqsave(lp->indirect_lock, flags);
temac_iow(lp, XTE_LSW0_OFFSET, (phy_id << 5) | reg);
rc = temac_indirect_in32(lp, XTE_MIIMAI_OFFSET);
mutex_unlock(lp->indirect_mutex);
rc = temac_indirect_in32_locked(lp, XTE_MIIMAI_OFFSET);
spin_unlock_irqrestore(lp->indirect_lock, flags);
dev_dbg(lp->dev, "temac_mdio_read(phy_id=%i, reg=%x) == %x\n",
phy_id, reg, rc);
@ -43,6 +44,7 @@ static int temac_mdio_read(struct mii_bus *bus, int phy_id, int reg)
static int temac_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 val)
{
struct temac_local *lp = bus->priv;
unsigned long flags;
dev_dbg(lp->dev, "temac_mdio_write(phy_id=%i, reg=%x, val=%x)\n",
phy_id, reg, val);
@ -50,10 +52,10 @@ static int temac_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 val)
/* First write the desired value into the write data register
* and then write the address into the access initiator register
*/
mutex_lock(lp->indirect_mutex);
temac_indirect_out32(lp, XTE_MGTDR_OFFSET, val);
temac_indirect_out32(lp, XTE_MIIMAI_OFFSET, (phy_id << 5) | reg);
mutex_unlock(lp->indirect_mutex);
spin_lock_irqsave(lp->indirect_lock, flags);
temac_indirect_out32_locked(lp, XTE_MGTDR_OFFSET, val);
temac_indirect_out32_locked(lp, XTE_MIIMAI_OFFSET, (phy_id << 5) | reg);
spin_unlock_irqrestore(lp->indirect_lock, flags);
return 0;
}
@ -87,9 +89,7 @@ int temac_mdio_setup(struct temac_local *lp, struct platform_device *pdev)
/* Enable the MDIO bus by asserting the enable bit and writing
* in the clock config */
mutex_lock(lp->indirect_mutex);
temac_indirect_out32(lp, XTE_MC_OFFSET, 1 << 6 | clk_div);
mutex_unlock(lp->indirect_mutex);
bus = devm_mdiobus_alloc(&pdev->dev);
if (!bus)
@ -116,10 +116,8 @@ int temac_mdio_setup(struct temac_local *lp, struct platform_device *pdev)
if (rc)
return rc;
mutex_lock(lp->indirect_mutex);
dev_dbg(lp->dev, "MDIO bus registered; MC:%x\n",
temac_indirect_in32(lp, XTE_MC_OFFSET));
mutex_unlock(lp->indirect_mutex);
return 0;
}

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@ -4,6 +4,7 @@
#include <linux/if_ether.h>
#include <linux/phy.h>
#include <linux/spinlock.h>
struct ll_temac_platform_data {
bool txcsum; /* Enable/disable TX checksum */
@ -21,7 +22,7 @@ struct ll_temac_platform_data {
* TEMAC IP block, the same mutex should be passed here, as
* they share the same DCR bus bridge.
*/
struct mutex *indirect_mutex;
spinlock_t *indirect_lock;
/* DMA channel control setup */
u8 tx_irq_timeout; /* TX Interrupt Delay Time-out */
u8 tx_irq_count; /* TX Interrupt Coalescing Threshold Count */