diff --git a/Documentation/ABI/testing/sysfs-class-cxl b/Documentation/ABI/testing/sysfs-class-cxl index 5941ff38d4a3..9ea01068a16c 100644 --- a/Documentation/ABI/testing/sysfs-class-cxl +++ b/Documentation/ABI/testing/sysfs-class-cxl @@ -146,3 +146,10 @@ Description: read/write user or factory image to be loaded. Default is to reload on PERST whichever image the card has loaded. + +What: /sys/class/cxl//reset +Date: October 2014 +Contact: linuxppc-dev@lists.ozlabs.org +Description: write only + Writing 1 will issue a PERST to card which may cause the card + to reload the FPGA depending on load_image_on_perst. diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h index 518c4c6e6151..6a6a487464c5 100644 --- a/drivers/misc/cxl/cxl.h +++ b/drivers/misc/cxl/cxl.h @@ -489,6 +489,7 @@ int cxl_alloc_irq_ranges(struct cxl_irq_ranges *irqs, struct cxl *adapter, unsig void cxl_release_irq_ranges(struct cxl_irq_ranges *irqs, struct cxl *adapter); int cxl_setup_irq(struct cxl *adapter, unsigned int hwirq, unsigned int virq); int cxl_update_image_control(struct cxl *adapter); +int cxl_reset(struct cxl *adapter); /* common == phyp + powernv */ struct cxl_process_element_common { diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c index a4a4e0217eed..428ea8ba25fc 100644 --- a/drivers/misc/cxl/pci.c +++ b/drivers/misc/cxl/pci.c @@ -21,6 +21,7 @@ #include #include /* for struct pci_controller */ #include +#include #include "cxl.h" @@ -741,6 +742,42 @@ static void cxl_remove_afu(struct cxl_afu *afu) device_unregister(&afu->dev); } +int cxl_reset(struct cxl *adapter) +{ + struct pci_dev *dev = to_pci_dev(adapter->dev.parent); + int rc; + int i; + u32 val; + + dev_info(&dev->dev, "CXL reset\n"); + + for (i = 0; i < adapter->slices; i++) + cxl_remove_afu(adapter->afu[i]); + + /* pcie_warm_reset requests a fundamental pci reset which includes a + * PERST assert/deassert. PERST triggers a loading of the image + * if "user" or "factory" is selected in sysfs */ + if ((rc = pci_set_pcie_reset_state(dev, pcie_warm_reset))) { + dev_err(&dev->dev, "cxl: pcie_warm_reset failed\n"); + return rc; + } + + /* the PERST done above fences the PHB. So, reset depends on EEH + * to unbind the driver, tell Sapphire to reinit the PHB, and rebind + * the driver. Do an mmio read explictly to ensure EEH notices the + * fenced PHB. Retry for a few seconds before giving up. */ + i = 0; + while (((val = mmio_read32be(adapter->p1_mmio)) != 0xffffffff) && + (i < 5)) { + msleep(500); + i++; + } + + if (val != 0xffffffff) + dev_err(&dev->dev, "cxl: PERST failed to trigger EEH\n"); + + return rc; +} static int cxl_map_adapter_regs(struct cxl *adapter, struct pci_dev *dev) { diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c index ed4ad461143c..adf1f6d84913 100644 --- a/drivers/misc/cxl/sysfs.c +++ b/drivers/misc/cxl/sysfs.c @@ -56,6 +56,23 @@ static ssize_t image_loaded_show(struct device *device, return scnprintf(buf, PAGE_SIZE, "factory\n"); } +static ssize_t reset_adapter_store(struct device *device, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct cxl *adapter = to_cxl_adapter(device); + int rc; + int val; + + rc = sscanf(buf, "%i", &val); + if ((rc != 1) || (val != 1)) + return -EINVAL; + + if ((rc = cxl_reset(adapter))) + return rc; + return count; +} + static ssize_t load_image_on_perst_show(struct device *device, struct device_attribute *attr, char *buf) @@ -100,6 +117,7 @@ static struct device_attribute adapter_attrs[] = { __ATTR_RO(base_image), __ATTR_RO(image_loaded), __ATTR_RW(load_image_on_perst), + __ATTR(reset, S_IWUSR, NULL, reset_adapter_store), };