This patch adds an interface on sysfs for userspace to request a card bitstream reload. It sets the appropriate register and try to perform a fundamental reset on the PCIe slot for the card to reload the bitstream from the chosen partition.
Signed-off-by: Kleber Sacilotto de Souza <[email protected]> --- Documentation/ABI/testing/sysfs-driver-genwqe | 9 +++ drivers/misc/genwqe/card_base.c | 90 +++++++++++++++++++++++++ drivers/misc/genwqe/card_sysfs.c | 25 +++++++ include/uapi/linux/genwqe/genwqe_card.h | 1 + 4 files changed, 125 insertions(+), 0 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-driver-genwqe b/Documentation/ABI/testing/sysfs-driver-genwqe index 1870737..64ac6d5 100644 --- a/Documentation/ABI/testing/sysfs-driver-genwqe +++ b/Documentation/ABI/testing/sysfs-driver-genwqe @@ -25,6 +25,15 @@ Date: Oct 2013 Contact: [email protected] Description: Interface to set the next bitstream to be used. +What: /sys/class/genwqe/genwqe<n>_card/reload_bitstream +Date: May 2014 +Contact: [email protected] +Description: Interface to trigger a PCIe card reset to reload the bitstream. + sudo sh -c 'echo 1 > \ + /sys/class/genwqe/genwqe0_card/reload_bitstream' + If successfully, the card will come back with the bitstream set + on 'next_bitstream'. + What: /sys/class/genwqe/genwqe<n>_card/tempsens Date: Oct 2013 Contact: [email protected] diff --git a/drivers/misc/genwqe/card_base.c b/drivers/misc/genwqe/card_base.c index 74d51c9..e6cc3e1 100644 --- a/drivers/misc/genwqe/card_base.c +++ b/drivers/misc/genwqe/card_base.c @@ -761,6 +761,89 @@ static u64 genwqe_fir_checking(struct genwqe_dev *cd) } /** + * genwqe_pci_fundamental_reset() - trigger a PCIe fundamental reset on the slot + * + * Note: pci_set_pcie_reset_state() is not implemented on all archs, so this + * reset method will not work in all cases. + * + * Return: 0 on success or error code from pci_set_pcie_reset_state() + */ +static int genwqe_pci_fundamental_reset(struct pci_dev *pci_dev) +{ + int rc; + + /* + * lock pci config space access from userspace, + * save state and issue PCIe fundamental reset + */ + pci_cfg_access_lock(pci_dev); + pci_save_state(pci_dev); + rc = pci_set_pcie_reset_state(pci_dev, pcie_warm_reset); + if (!rc) { + /* keep PCIe reset asserted for 250ms */ + msleep(250); + pci_set_pcie_reset_state(pci_dev, pcie_deassert_reset); + /* Wait for 2s to reload flash and train the link */ + msleep(2000); + } + pci_restore_state(pci_dev); + pci_cfg_access_unlock(pci_dev); + return rc; +} + +/* + * genwqe_reload_bistream() - reload card bitstream + * + * Set the appropriate register and call fundamental reset to reaload the card + * bitstream. + * + * Return: 0 on success, error code otherwise + */ +static int genwqe_reload_bistream(struct genwqe_dev *cd) +{ + struct pci_dev *pci_dev = cd->pci_dev; + int rc; + + dev_info(&pci_dev->dev, + "[%s] resetting card for bitstream reload\n", + __func__); + + genwqe_stop(cd); + + /* + * Cause a CPLD reprogram with the 'next_bitstream' + * partition on PCIe hot or fundamental reset + */ + __genwqe_writeq(cd, IO_SLC_CFGREG_SOFTRESET, + (cd->softreset & 0xcull) | 0x70ull); + + rc = genwqe_pci_fundamental_reset(pci_dev); + if (rc) { + /* + * A fundamental reset failure can be caused + * by lack of support on the arch, so we just + * log the error and try to start the card + * again. + */ + dev_err(&pci_dev->dev, + "[%s] err: failed to reset card for bitstream reload\n", + __func__); + } + + rc = genwqe_start(cd); + if (rc) { + dev_err(&pci_dev->dev, + "[%s] err: cannot start card services! (err=%d)\n", + __func__, rc); + return rc; + } + dev_info(&pci_dev->dev, + "[%s] card reloaded\n", __func__); + return 0; +} + + +/** * genwqe_health_thread() - Health checking thread * * This thread is only started for the PF of the card. @@ -846,6 +929,13 @@ static int genwqe_health_thread(void *data) } } + if (cd->card_state == GENWQE_CARD_RELOAD_BITSTREAM) { + /* Userspace requested card bitstream reload */ + rc = genwqe_reload_bistream(cd); + if (rc) + goto fatal_error; + } + cd->last_gfir = gfir; cond_resched(); } diff --git a/drivers/misc/genwqe/card_sysfs.c b/drivers/misc/genwqe/card_sysfs.c index a72a992..7232e40 100644 --- a/drivers/misc/genwqe/card_sysfs.c +++ b/drivers/misc/genwqe/card_sysfs.c @@ -223,6 +223,30 @@ static ssize_t next_bitstream_store(struct device *dev, } static DEVICE_ATTR_RW(next_bitstream); +static ssize_t reload_bitstream_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int reload; + struct genwqe_dev *cd = dev_get_drvdata(dev); + + if (kstrtoint(buf, 0, &reload) < 0) + return -EINVAL; + + if (reload == 0x1) { + if (cd->card_state == GENWQE_CARD_UNUSED || + cd->card_state == GENWQE_CARD_USED) + cd->card_state = GENWQE_CARD_RELOAD_BITSTREAM; + else + return -EIO; + } else { + return -EINVAL; + } + + return count; +} +static DEVICE_ATTR_WO(reload_bitstream); + /* * Create device_attribute structures / params: name, mode, show, store * additional flag if valid in VF @@ -239,6 +263,7 @@ static struct attribute *genwqe_attributes[] = { &dev_attr_status.attr, &dev_attr_freerunning_timer.attr, &dev_attr_queue_working_time.attr, + &dev_attr_reload_bitstream.attr, NULL, }; diff --git a/include/uapi/linux/genwqe/genwqe_card.h b/include/uapi/linux/genwqe/genwqe_card.h index 795e957..4fc065f 100644 --- a/include/uapi/linux/genwqe/genwqe_card.h +++ b/include/uapi/linux/genwqe/genwqe_card.h @@ -328,6 +328,7 @@ enum genwqe_card_state { GENWQE_CARD_UNUSED = 0, GENWQE_CARD_USED = 1, GENWQE_CARD_FATAL_ERROR = 2, + GENWQE_CARD_RELOAD_BITSTREAM = 3, GENWQE_CARD_STATE_MAX, }; -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
