When passing through PE to guest, that's possibly in frozen
state. The driver for the pass-through devices on guest side
can't be loaded successfully as reported. We already had one
gate in eeh_dev_open() to clear PE frozen state accordingly,
but that's not enough because the function is only called at
QEMU startup for once.
The patch adds another gate in eeh_pe_set_option() so that the
PE frozen state can be cleared at QEMU restart time.
Signed-off-by: Gavin Shan <gws...@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/eeh.h | 1 +
arch/powerpc/kernel/eeh.c | 60 ++++++++++++++++++++++--------------------
2 files changed, 33 insertions(+), 28 deletions(-)
diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index 1951d07..9bf4a5e 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -281,6 +281,7 @@ void eeh_add_device_late(struct pci_dev *);
void eeh_add_device_tree_late(struct pci_bus *);
void eeh_add_sysfs_files(struct pci_bus *);
void eeh_remove_device(struct pci_dev *);
+int eeh_unfreeze_pe(struct eeh_pe *pe, bool sw_state);
int eeh_dev_open(struct pci_dev *pdev);
void eeh_dev_release(struct pci_dev *pdev);
struct eeh_pe *eeh_iommu_group_to_pe(struct iommu_group *group);
diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
index 09bcf95..9678e16 100644
--- a/arch/powerpc/kernel/eeh.c
+++ b/arch/powerpc/kernel/eeh.c
@@ -1164,6 +1164,31 @@ void eeh_remove_device(struct pci_dev *dev)
edev->mode &= ~EEH_DEV_SYSFS;
}
+int eeh_unfreeze_pe(struct eeh_pe *pe, bool sw_state)
+{
+ int ret;
+
+ ret = eeh_pci_enable(pe, EEH_OPT_THAW_MMIO);
+ if (ret) {
+ pr_warn("%s: Failure %d enabling IO on PHB#%x-PE#%x\n",
+ __func__, ret, pe->phb->global_number, pe->addr);
+ return ret;
+ }
+
+ ret = eeh_pci_enable(pe, EEH_OPT_THAW_DMA);
+ if (ret) {
+ pr_warn("%s: Failure %d enabling DMA on PHB#%x-PE#%x\n",
+ __func__, ret, pe->phb->global_number, pe->addr);
+ return ret;
+ }
+
+ /* Clear software isolated state */
+ if (sw_state && (pe->state & EEH_PE_ISOLATED))
+ eeh_pe_state_clear(pe, EEH_PE_ISOLATED);
+
+ return ret;
+}
+
/**
* eeh_dev_open - Increase count of pass through devices for PE
* @pdev: PCI device
@@ -1176,7 +1201,6 @@ void eeh_remove_device(struct pci_dev *dev)
int eeh_dev_open(struct pci_dev *pdev)
{
struct eeh_dev *edev;
- int flag = (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE);
int ret = -ENODEV;
mutex_lock(&eeh_dev_mutex);
@@ -1196,31 +1220,9 @@ int eeh_dev_open(struct pci_dev *pdev)
* in frozen PE won't work properly. Clear the frozen state
* in advance.
*/
- ret = eeh_ops->get_state(edev->pe, NULL);
- if (ret > 0 && ret != EEH_STATE_NOT_SUPPORT &&
- (ret & flag) != flag) {
- ret = eeh_ops->set_option(edev->pe, EEH_OPT_THAW_MMIO);
- if (ret) {
- pr_warn("%s: Failure %d enabling MMIO "
- "for PHB#%x-PE#%x\n",
- __func__, ret, edev->phb->global_number,
- edev->pe->addr);
- goto out;
- }
-
- ret = eeh_ops->set_option(edev->pe, EEH_OPT_THAW_DMA);
- if (ret) {
- pr_warn("%s: Failure %d enabling DMA "
- "for PHB#%x-PE#%x\n",
- __func__, ret, edev->phb->global_number,
- edev->pe->addr);
- goto out;
- }
- }
-
- /* Clear software isolated state */
- if (edev->pe->state & EEH_PE_ISOLATED)
- eeh_pe_state_clear(edev->pe, EEH_PE_ISOLATED);
+ ret = eeh_unfreeze_pe(edev->pe, true);
+ if (ret)
+ goto out;
/* Increase PE's pass through count */
atomic_inc(&edev->pe->pass_dev_cnt);
@@ -1338,8 +1340,10 @@ int eeh_pe_set_option(struct eeh_pe *pe, int option)
*/
switch (option) {
case EEH_OPT_ENABLE:
- if (eeh_enabled())
+ if (eeh_enabled()) {
+ ret = eeh_unfreeze_pe(pe, true);
break;
+ }
ret = -EIO;
break;
case EEH_OPT_DISABLE:
@@ -1351,7 +1355,7 @@ int eeh_pe_set_option(struct eeh_pe *pe, int option)
break;
}
- ret = eeh_ops->set_option(pe, option);
+ ret = eeh_pci_enable(pe, option);
break;
default:
pr_debug("%s: Option %d out of range (%d, %d)\n",
--
1.8.3.2
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