linux/drivers/net/wireless/ath/ath9k/pci.c
Stanislaw Gruszka d4930086bd ath9k: skip ->config_pci_powersave() if PCIe port has ASPM disabled
We receive many bug reports about system hang during suspend/resume
when ath9k driver is in use. Adrian Chadd remarked that this problem
happens on systems that have ASPM disabled.

To do not hit the bug, skip doing ->config_pci_powersave magic if PCIe
downstream port device, which ath9k device is connected to, has ASPM
disabled.

Bug was introduced by:

commit 53bc7aa08b
Author: Vivek Natarajan <vnatarajan@atheros.com>
Date:   Mon Apr 5 14:48:04 2010 +0530

    ath9k: Add support for newer AR9285 chipsets.

Patch should address:
https://bugzilla.kernel.org/show_bug.cgi?id=37462
https://bugzilla.kernel.org/show_bug.cgi?id=37082
https://bugzilla.redhat.com/show_bug.cgi?id=697157

however I did not receive confirmation about that, except from Camilo
Mesias, whose system stops hang regularly with this patch (but still
hangs from time to time, but this is probably some other bug).

Tested-by: Camilo Mesias <camilo@mesias.co.uk>
Cc: stable@kernel.org # 2.6.35+
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-08-01 13:46:46 -04:00

389 lines
10 KiB
C

/*
* Copyright (c) 2008-2011 Atheros Communications Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <linux/nl80211.h>
#include <linux/pci.h>
#include <linux/pci-aspm.h>
#include <linux/ath9k_platform.h>
#include "ath9k.h"
static DEFINE_PCI_DEVICE_TABLE(ath_pci_id_table) = {
{ PCI_VDEVICE(ATHEROS, 0x0023) }, /* PCI */
{ PCI_VDEVICE(ATHEROS, 0x0024) }, /* PCI-E */
{ PCI_VDEVICE(ATHEROS, 0x0027) }, /* PCI */
{ PCI_VDEVICE(ATHEROS, 0x0029) }, /* PCI */
{ PCI_VDEVICE(ATHEROS, 0x002A) }, /* PCI-E */
{ PCI_VDEVICE(ATHEROS, 0x002B) }, /* PCI-E */
{ PCI_VDEVICE(ATHEROS, 0x002C) }, /* PCI-E 802.11n bonded out */
{ PCI_VDEVICE(ATHEROS, 0x002D) }, /* PCI */
{ PCI_VDEVICE(ATHEROS, 0x002E) }, /* PCI-E */
{ PCI_VDEVICE(ATHEROS, 0x0030) }, /* PCI-E AR9300 */
{ PCI_VDEVICE(ATHEROS, 0x0032) }, /* PCI-E AR9485 */
{ 0 }
};
/* return bus cachesize in 4B word units */
static void ath_pci_read_cachesize(struct ath_common *common, int *csz)
{
struct ath_softc *sc = (struct ath_softc *) common->priv;
u8 u8tmp;
pci_read_config_byte(to_pci_dev(sc->dev), PCI_CACHE_LINE_SIZE, &u8tmp);
*csz = (int)u8tmp;
/*
* This check was put in to avoid "unpleasant" consequences if
* the bootrom has not fully initialized all PCI devices.
* Sometimes the cache line size register is not set
*/
if (*csz == 0)
*csz = DEFAULT_CACHELINE >> 2; /* Use the default size */
}
static bool ath_pci_eeprom_read(struct ath_common *common, u32 off, u16 *data)
{
struct ath_softc *sc = (struct ath_softc *) common->priv;
struct ath9k_platform_data *pdata = sc->dev->platform_data;
if (pdata) {
if (off >= (ARRAY_SIZE(pdata->eeprom_data))) {
ath_err(common,
"%s: eeprom read failed, offset %08x is out of range\n",
__func__, off);
}
*data = pdata->eeprom_data[off];
} else {
struct ath_hw *ah = (struct ath_hw *) common->ah;
common->ops->read(ah, AR5416_EEPROM_OFFSET +
(off << AR5416_EEPROM_S));
if (!ath9k_hw_wait(ah,
AR_EEPROM_STATUS_DATA,
AR_EEPROM_STATUS_DATA_BUSY |
AR_EEPROM_STATUS_DATA_PROT_ACCESS, 0,
AH_WAIT_TIMEOUT)) {
return false;
}
*data = MS(common->ops->read(ah, AR_EEPROM_STATUS_DATA),
AR_EEPROM_STATUS_DATA_VAL);
}
return true;
}
/*
* Bluetooth coexistance requires disabling ASPM.
*/
static void ath_pci_bt_coex_prep(struct ath_common *common)
{
struct ath_softc *sc = (struct ath_softc *) common->priv;
struct pci_dev *pdev = to_pci_dev(sc->dev);
u8 aspm;
if (!pci_is_pcie(pdev))
return;
pci_read_config_byte(pdev, ATH_PCIE_CAP_LINK_CTRL, &aspm);
aspm &= ~(ATH_PCIE_CAP_LINK_L0S | ATH_PCIE_CAP_LINK_L1);
pci_write_config_byte(pdev, ATH_PCIE_CAP_LINK_CTRL, aspm);
}
static void ath_pci_extn_synch_enable(struct ath_common *common)
{
struct ath_softc *sc = (struct ath_softc *) common->priv;
struct pci_dev *pdev = to_pci_dev(sc->dev);
u8 lnkctl;
pci_read_config_byte(pdev, sc->sc_ah->caps.pcie_lcr_offset, &lnkctl);
lnkctl |= PCI_EXP_LNKCTL_ES;
pci_write_config_byte(pdev, sc->sc_ah->caps.pcie_lcr_offset, lnkctl);
}
static void ath_pci_aspm_init(struct ath_common *common)
{
struct ath_softc *sc = (struct ath_softc *) common->priv;
struct ath_hw *ah = sc->sc_ah;
struct pci_dev *pdev = to_pci_dev(sc->dev);
struct pci_dev *parent;
int pos;
u8 aspm;
if (!pci_is_pcie(pdev))
return;
parent = pdev->bus->self;
if (WARN_ON(!parent))
return;
pos = pci_pcie_cap(parent);
pci_read_config_byte(parent, pos + PCI_EXP_LNKCTL, &aspm);
if (aspm & (PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1)) {
ah->aspm_enabled = true;
/* Initialize PCIe PM and SERDES registers. */
ath9k_hw_configpcipowersave(ah, 0, 0);
}
}
static const struct ath_bus_ops ath_pci_bus_ops = {
.ath_bus_type = ATH_PCI,
.read_cachesize = ath_pci_read_cachesize,
.eeprom_read = ath_pci_eeprom_read,
.bt_coex_prep = ath_pci_bt_coex_prep,
.extn_synch_en = ath_pci_extn_synch_enable,
.aspm_init = ath_pci_aspm_init,
};
static int ath_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
void __iomem *mem;
struct ath_softc *sc;
struct ieee80211_hw *hw;
u8 csz;
u16 subsysid;
u32 val;
int ret = 0;
char hw_name[64];
if (pci_enable_device(pdev))
return -EIO;
ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
if (ret) {
printk(KERN_ERR "ath9k: 32-bit DMA not available\n");
goto err_dma;
}
ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
if (ret) {
printk(KERN_ERR "ath9k: 32-bit DMA consistent "
"DMA enable failed\n");
goto err_dma;
}
/*
* Cache line size is used to size and align various
* structures used to communicate with the hardware.
*/
pci_read_config_byte(pdev, PCI_CACHE_LINE_SIZE, &csz);
if (csz == 0) {
/*
* Linux 2.4.18 (at least) writes the cache line size
* register as a 16-bit wide register which is wrong.
* We must have this setup properly for rx buffer
* DMA to work so force a reasonable value here if it
* comes up zero.
*/
csz = L1_CACHE_BYTES / sizeof(u32);
pci_write_config_byte(pdev, PCI_CACHE_LINE_SIZE, csz);
}
/*
* The default setting of latency timer yields poor results,
* set it to the value used by other systems. It may be worth
* tweaking this setting more.
*/
pci_write_config_byte(pdev, PCI_LATENCY_TIMER, 0xa8);
pci_set_master(pdev);
/*
* Disable the RETRY_TIMEOUT register (0x41) to keep
* PCI Tx retries from interfering with C3 CPU state.
*/
pci_read_config_dword(pdev, 0x40, &val);
if ((val & 0x0000ff00) != 0)
pci_write_config_dword(pdev, 0x40, val & 0xffff00ff);
ret = pci_request_region(pdev, 0, "ath9k");
if (ret) {
dev_err(&pdev->dev, "PCI memory region reserve error\n");
ret = -ENODEV;
goto err_region;
}
mem = pci_iomap(pdev, 0, 0);
if (!mem) {
printk(KERN_ERR "PCI memory map error\n") ;
ret = -EIO;
goto err_iomap;
}
hw = ieee80211_alloc_hw(sizeof(struct ath_softc), &ath9k_ops);
if (!hw) {
dev_err(&pdev->dev, "No memory for ieee80211_hw\n");
ret = -ENOMEM;
goto err_alloc_hw;
}
SET_IEEE80211_DEV(hw, &pdev->dev);
pci_set_drvdata(pdev, hw);
sc = hw->priv;
sc->hw = hw;
sc->dev = &pdev->dev;
sc->mem = mem;
/* Will be cleared in ath9k_start() */
sc->sc_flags |= SC_OP_INVALID;
ret = request_irq(pdev->irq, ath_isr, IRQF_SHARED, "ath9k", sc);
if (ret) {
dev_err(&pdev->dev, "request_irq failed\n");
goto err_irq;
}
sc->irq = pdev->irq;
pci_read_config_word(pdev, PCI_SUBSYSTEM_ID, &subsysid);
ret = ath9k_init_device(id->device, sc, subsysid, &ath_pci_bus_ops);
if (ret) {
dev_err(&pdev->dev, "Failed to initialize device\n");
goto err_init;
}
ath9k_hw_name(sc->sc_ah, hw_name, sizeof(hw_name));
wiphy_info(hw->wiphy, "%s mem=0x%lx, irq=%d\n",
hw_name, (unsigned long)mem, pdev->irq);
return 0;
err_init:
free_irq(sc->irq, sc);
err_irq:
ieee80211_free_hw(hw);
err_alloc_hw:
pci_iounmap(pdev, mem);
err_iomap:
pci_release_region(pdev, 0);
err_region:
/* Nothing */
err_dma:
pci_disable_device(pdev);
return ret;
}
static void ath_pci_remove(struct pci_dev *pdev)
{
struct ieee80211_hw *hw = pci_get_drvdata(pdev);
struct ath_softc *sc = hw->priv;
void __iomem *mem = sc->mem;
if (!is_ath9k_unloaded)
sc->sc_ah->ah_flags |= AH_UNPLUGGED;
ath9k_deinit_device(sc);
free_irq(sc->irq, sc);
ieee80211_free_hw(sc->hw);
pci_iounmap(pdev, mem);
pci_disable_device(pdev);
pci_release_region(pdev, 0);
}
#ifdef CONFIG_PM
static int ath_pci_suspend(struct device *device)
{
struct pci_dev *pdev = to_pci_dev(device);
struct ieee80211_hw *hw = pci_get_drvdata(pdev);
struct ath_softc *sc = hw->priv;
ath9k_hw_set_gpio(sc->sc_ah, sc->sc_ah->led_pin, 1);
/* The device has to be moved to FULLSLEEP forcibly.
* Otherwise the chip never moved to full sleep,
* when no interface is up.
*/
ath9k_hw_setpower(sc->sc_ah, ATH9K_PM_FULL_SLEEP);
return 0;
}
static int ath_pci_resume(struct device *device)
{
struct pci_dev *pdev = to_pci_dev(device);
struct ieee80211_hw *hw = pci_get_drvdata(pdev);
struct ath_softc *sc = hw->priv;
u32 val;
/*
* Suspend/Resume resets the PCI configuration space, so we have to
* re-disable the RETRY_TIMEOUT register (0x41) to keep
* PCI Tx retries from interfering with C3 CPU state
*/
pci_read_config_dword(pdev, 0x40, &val);
if ((val & 0x0000ff00) != 0)
pci_write_config_dword(pdev, 0x40, val & 0xffff00ff);
/* Enable LED */
ath9k_hw_cfg_output(sc->sc_ah, sc->sc_ah->led_pin,
AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
ath9k_hw_set_gpio(sc->sc_ah, sc->sc_ah->led_pin, 1);
/*
* Reset key cache to sane defaults (all entries cleared) instead of
* semi-random values after suspend/resume.
*/
ath9k_ps_wakeup(sc);
ath9k_init_crypto(sc);
ath9k_ps_restore(sc);
sc->ps_idle = true;
ath_radio_disable(sc, hw);
return 0;
}
static const struct dev_pm_ops ath9k_pm_ops = {
.suspend = ath_pci_suspend,
.resume = ath_pci_resume,
.freeze = ath_pci_suspend,
.thaw = ath_pci_resume,
.poweroff = ath_pci_suspend,
.restore = ath_pci_resume,
};
#define ATH9K_PM_OPS (&ath9k_pm_ops)
#else /* !CONFIG_PM */
#define ATH9K_PM_OPS NULL
#endif /* !CONFIG_PM */
MODULE_DEVICE_TABLE(pci, ath_pci_id_table);
static struct pci_driver ath_pci_driver = {
.name = "ath9k",
.id_table = ath_pci_id_table,
.probe = ath_pci_probe,
.remove = ath_pci_remove,
.driver.pm = ATH9K_PM_OPS,
};
int ath_pci_init(void)
{
return pci_register_driver(&ath_pci_driver);
}
void ath_pci_exit(void)
{
pci_unregister_driver(&ath_pci_driver);
}