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authorBjorn Helgaas <bhelgaas@google.com>2018-08-15 22:59:06 +0300
committerBjorn Helgaas <bhelgaas@google.com>2018-08-15 22:59:06 +0300
commit3a48dc6fc260c9cac302a9ffaeab95359431c485 (patch)
tree7dc85ea850ef81c756b55e2bdec5b7b6146f535e /drivers/pci/quirks.c
parente7aaf90f9d9dbbba54f67c653a1c56c2bf117268 (diff)
parent7695e73f3db4576ef3ce05063c28e9a673425763 (diff)
downloadlinux-3a48dc6fc260c9cac302a9ffaeab95359431c485.tar.xz
Merge branch 'pci/virtualization'
- To avoid bus errors, enable PASID only if entire path supports End-End TLP prefixes (Sinan Kaya) - Unify slot and bus reset functions and remove hotplug knowledge from callers (Sinan Kaya) - Add Function-Level Reset quirks for Intel and Samsung NVMe devices to fix guest reboot issues (Alex Williamson) - Add function 1 DMA alias quirk for Marvell 88SS9183 PCIe SSD Controller (Bjorn Helgaas) * pci/virtualization: PCI: Add function 1 DMA alias quirk for Marvell 88SS9183 PCI: Delay after FLR of Intel DC P3700 NVMe PCI: Disable Samsung SM961/PM961 NVMe before FLR PCI: Export pcie_has_flr() PCI: Rename pci_try_reset_bus() to pci_reset_bus() PCI: Deprecate pci_reset_bus() and pci_reset_slot() functions PCI: Unify try slot and bus reset API PCI: Hide pci_reset_bridge_secondary_bus() from drivers IB/hfi1: Use pci_try_reset_bus() for initiating PCI Secondary Bus Reset PCI: Handle error return from pci_reset_bridge_secondary_bus() PCI/IOV: Tidy pci_sriov_set_totalvfs() PCI: Enable PASID only if entire path supports End-End TLP prefixes # Conflicts: # drivers/pci/hotplug/pciehp_hpc.c
Diffstat (limited to 'drivers/pci/quirks.c')
-rw-r--r--drivers/pci/quirks.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 6b635022f2fe..b2e6c02385e5 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -25,6 +25,7 @@
#include <linux/sched.h>
#include <linux/ktime.h>
#include <linux/mm.h>
+#include <linux/nvme.h>
#include <linux/platform_data/x86/apple.h>
#include <linux/pm_runtime.h>
#include <linux/switchtec.h>
@@ -3667,6 +3668,108 @@ static int reset_chelsio_generic_dev(struct pci_dev *dev, int probe)
#define PCI_DEVICE_ID_INTEL_IVB_M_VGA 0x0156
#define PCI_DEVICE_ID_INTEL_IVB_M2_VGA 0x0166
+/*
+ * The Samsung SM961/PM961 controller can sometimes enter a fatal state after
+ * FLR where config space reads from the device return -1. We seem to be
+ * able to avoid this condition if we disable the NVMe controller prior to
+ * FLR. This quirk is generic for any NVMe class device requiring similar
+ * assistance to quiesce the device prior to FLR.
+ *
+ * NVMe specification: https://nvmexpress.org/resources/specifications/
+ * Revision 1.0e:
+ * Chapter 2: Required and optional PCI config registers
+ * Chapter 3: NVMe control registers
+ * Chapter 7.3: Reset behavior
+ */
+static int nvme_disable_and_flr(struct pci_dev *dev, int probe)
+{
+ void __iomem *bar;
+ u16 cmd;
+ u32 cfg;
+
+ if (dev->class != PCI_CLASS_STORAGE_EXPRESS ||
+ !pcie_has_flr(dev) || !pci_resource_start(dev, 0))
+ return -ENOTTY;
+
+ if (probe)
+ return 0;
+
+ bar = pci_iomap(dev, 0, NVME_REG_CC + sizeof(cfg));
+ if (!bar)
+ return -ENOTTY;
+
+ pci_read_config_word(dev, PCI_COMMAND, &cmd);
+ pci_write_config_word(dev, PCI_COMMAND, cmd | PCI_COMMAND_MEMORY);
+
+ cfg = readl(bar + NVME_REG_CC);
+
+ /* Disable controller if enabled */
+ if (cfg & NVME_CC_ENABLE) {
+ u32 cap = readl(bar + NVME_REG_CAP);
+ unsigned long timeout;
+
+ /*
+ * Per nvme_disable_ctrl() skip shutdown notification as it
+ * could complete commands to the admin queue. We only intend
+ * to quiesce the device before reset.
+ */
+ cfg &= ~(NVME_CC_SHN_MASK | NVME_CC_ENABLE);
+
+ writel(cfg, bar + NVME_REG_CC);
+
+ /*
+ * Some controllers require an additional delay here, see
+ * NVME_QUIRK_DELAY_BEFORE_CHK_RDY. None of those are yet
+ * supported by this quirk.
+ */
+
+ /* Cap register provides max timeout in 500ms increments */
+ timeout = ((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
+
+ for (;;) {
+ u32 status = readl(bar + NVME_REG_CSTS);
+
+ /* Ready status becomes zero on disable complete */
+ if (!(status & NVME_CSTS_RDY))
+ break;
+
+ msleep(100);
+
+ if (time_after(jiffies, timeout)) {
+ pci_warn(dev, "Timeout waiting for NVMe ready status to clear after disable\n");
+ break;
+ }
+ }
+ }
+
+ pci_iounmap(dev, bar);
+
+ pcie_flr(dev);
+
+ return 0;
+}
+
+/*
+ * Intel DC P3700 NVMe controller will timeout waiting for ready status
+ * to change after NVMe enable if the driver starts interacting with the
+ * device too soon after FLR. A 250ms delay after FLR has heuristically
+ * proven to produce reliably working results for device assignment cases.
+ */
+static int delay_250ms_after_flr(struct pci_dev *dev, int probe)
+{
+ if (!pcie_has_flr(dev))
+ return -ENOTTY;
+
+ if (probe)
+ return 0;
+
+ pcie_flr(dev);
+
+ msleep(250);
+
+ return 0;
+}
+
static const struct pci_dev_reset_methods pci_dev_reset_methods[] = {
{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82599_SFP_VF,
reset_intel_82599_sfp_virtfn },
@@ -3674,6 +3777,8 @@ static const struct pci_dev_reset_methods pci_dev_reset_methods[] = {
reset_ivb_igd },
{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IVB_M2_VGA,
reset_ivb_igd },
+ { PCI_VENDOR_ID_SAMSUNG, 0xa804, nvme_disable_and_flr },
+ { PCI_VENDOR_ID_INTEL, 0x0953, delay_250ms_after_flr },
{ PCI_VENDOR_ID_CHELSIO, PCI_ANY_ID,
reset_chelsio_generic_dev },
{ 0 }
@@ -3743,6 +3848,9 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x917a,
/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c78 */
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x9182,
quirk_dma_func1_alias);
+/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c134 */
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x9183,
+ quirk_dma_func1_alias);
/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c46 */
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x91a0,
quirk_dma_func1_alias);