WSL2-Linux-Kernel/arch/powerpc/platforms/powernv/pci.c

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C
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Support PCI/PCIe on PowerNV platforms
*
* Copyright 2011 Benjamin Herrenschmidt, IBM Corp.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/msi.h>
#include <linux/iommu.h>
#include <linux/sched/mm.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/machdep.h>
#include <asm/msi_bitmap.h>
#include <asm/ppc-pci.h>
#include <asm/pnv-pci.h>
#include <asm/opal.h>
#include <asm/iommu.h>
#include <asm/tce.h>
#include <asm/firmware.h>
#include <asm/eeh_event.h>
#include <asm/eeh.h>
#include "powernv.h"
#include "pci.h"
static DEFINE_MUTEX(tunnel_mutex);
int pnv_pci_get_slot_id(struct device_node *np, uint64_t *id)
{
struct device_node *parent = np;
u32 bdfn;
u64 phbid;
int ret;
ret = of_property_read_u32(np, "reg", &bdfn);
if (ret)
return -ENXIO;
bdfn = ((bdfn & 0x00ffff00) >> 8);
while ((parent = of_get_parent(parent))) {
if (!PCI_DN(parent)) {
of_node_put(parent);
break;
}
if (!of_device_is_compatible(parent, "ibm,ioda2-phb")) {
of_node_put(parent);
continue;
}
ret = of_property_read_u64(parent, "ibm,opal-phbid", &phbid);
if (ret) {
of_node_put(parent);
return -ENXIO;
}
*id = PCI_SLOT_ID(phbid, bdfn);
return 0;
}
return -ENODEV;
}
EXPORT_SYMBOL_GPL(pnv_pci_get_slot_id);
int pnv_pci_get_device_tree(uint32_t phandle, void *buf, uint64_t len)
{
int64_t rc;
if (!opal_check_token(OPAL_GET_DEVICE_TREE))
return -ENXIO;
rc = opal_get_device_tree(phandle, (uint64_t)buf, len);
if (rc < OPAL_SUCCESS)
return -EIO;
return rc;
}
EXPORT_SYMBOL_GPL(pnv_pci_get_device_tree);
int pnv_pci_get_presence_state(uint64_t id, uint8_t *state)
{
int64_t rc;
if (!opal_check_token(OPAL_PCI_GET_PRESENCE_STATE))
return -ENXIO;
rc = opal_pci_get_presence_state(id, (uint64_t)state);
if (rc != OPAL_SUCCESS)
return -EIO;
return 0;
}
EXPORT_SYMBOL_GPL(pnv_pci_get_presence_state);
int pnv_pci_get_power_state(uint64_t id, uint8_t *state)
{
int64_t rc;
if (!opal_check_token(OPAL_PCI_GET_POWER_STATE))
return -ENXIO;
rc = opal_pci_get_power_state(id, (uint64_t)state);
if (rc != OPAL_SUCCESS)
return -EIO;
return 0;
}
EXPORT_SYMBOL_GPL(pnv_pci_get_power_state);
int pnv_pci_set_power_state(uint64_t id, uint8_t state, struct opal_msg *msg)
{
struct opal_msg m;
int token, ret;
int64_t rc;
if (!opal_check_token(OPAL_PCI_SET_POWER_STATE))
return -ENXIO;
token = opal_async_get_token_interruptible();
if (unlikely(token < 0))
return token;
rc = opal_pci_set_power_state(token, id, (uint64_t)&state);
if (rc == OPAL_SUCCESS) {
ret = 0;
goto exit;
} else if (rc != OPAL_ASYNC_COMPLETION) {
ret = -EIO;
goto exit;
}
ret = opal_async_wait_response(token, &m);
if (ret < 0)
goto exit;
if (msg) {
ret = 1;
memcpy(msg, &m, sizeof(m));
}
exit:
opal_async_release_token(token);
return ret;
}
EXPORT_SYMBOL_GPL(pnv_pci_set_power_state);
int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
{
struct pci_controller *hose = pci_bus_to_host(pdev->bus);
struct pnv_phb *phb = hose->private_data;
struct msi_desc *entry;
struct msi_msg msg;
int hwirq;
unsigned int virq;
int rc;
if (WARN_ON(!phb) || !phb->msi_bmp.bitmap)
return -ENODEV;
if (pdev->no_64bit_msi && !phb->msi32_support)
return -ENODEV;
for_each_pci_msi_entry(entry, pdev) {
if (!entry->msi_attrib.is_64 && !phb->msi32_support) {
pr_warn("%s: Supports only 64-bit MSIs\n",
pci_name(pdev));
return -ENXIO;
}
hwirq = msi_bitmap_alloc_hwirqs(&phb->msi_bmp, 1);
if (hwirq < 0) {
pr_warn("%s: Failed to find a free MSI\n",
pci_name(pdev));
return -ENOSPC;
}
virq = irq_create_mapping(NULL, phb->msi_base + hwirq);
if (!virq) {
pr_warn("%s: Failed to map MSI to linux irq\n",
pci_name(pdev));
msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, 1);
return -ENOMEM;
}
rc = phb->msi_setup(phb, pdev, phb->msi_base + hwirq,
virq, entry->msi_attrib.is_64, &msg);
if (rc) {
pr_warn("%s: Failed to setup MSI\n", pci_name(pdev));
irq_dispose_mapping(virq);
msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, 1);
return rc;
}
irq_set_msi_desc(virq, entry);
pci_write_msi_msg(virq, &msg);
}
return 0;
}
void pnv_teardown_msi_irqs(struct pci_dev *pdev)
{
struct pci_controller *hose = pci_bus_to_host(pdev->bus);
struct pnv_phb *phb = hose->private_data;
struct msi_desc *entry;
powerpc/MSI: Fix race condition in tearing down MSI interrupts This fixes a race which can result in the same virtual IRQ number being assigned to two different MSI interrupts. The most visible consequence of that is usually a warning and stack trace from the sysfs code about an attempt to create a duplicate entry in sysfs. The race happens when one CPU (say CPU 0) is disposing of an MSI while another CPU (say CPU 1) is setting up an MSI. CPU 0 calls (for example) pnv_teardown_msi_irqs(), which calls msi_bitmap_free_hwirqs() to indicate that the MSI (i.e. its hardware IRQ number) is no longer in use. Then, before CPU 0 gets to calling irq_dispose_mapping() to free up the virtal IRQ number, CPU 1 comes in and calls msi_bitmap_alloc_hwirqs() to allocate an MSI, and gets the same hardware IRQ number that CPU 0 just freed. CPU 1 then calls irq_create_mapping() to get a virtual IRQ number, which sees that there is currently a mapping for that hardware IRQ number and returns the corresponding virtual IRQ number (which is the same virtual IRQ number that CPU 0 was using). CPU 0 then calls irq_dispose_mapping() and frees that virtual IRQ number. Now, if another CPU comes along and calls irq_create_mapping(), it is likely to get the virtual IRQ number that was just freed, resulting in the same virtual IRQ number apparently being used for two different hardware interrupts. To fix this race, we just move the call to msi_bitmap_free_hwirqs() to after the call to irq_dispose_mapping(). Since virq_to_hw() doesn't work for the virtual IRQ number after irq_dispose_mapping() has been called, we need to call it before irq_dispose_mapping() and remember the result for the msi_bitmap_free_hwirqs() call. The pattern of calling msi_bitmap_free_hwirqs() before irq_dispose_mapping() appears in 5 places under arch/powerpc, and appears to have originated in commit 05af7bd2d75e ("[POWERPC] MPIC U3/U4 MSI backend") from 2007. Fixes: 05af7bd2d75e ("[POWERPC] MPIC U3/U4 MSI backend") Cc: stable@vger.kernel.org # v2.6.22+ Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-09-10 07:36:21 +03:00
irq_hw_number_t hwirq;
if (WARN_ON(!phb))
return;
for_each_pci_msi_entry(entry, pdev) {
if (!entry->irq)
continue;
powerpc/MSI: Fix race condition in tearing down MSI interrupts This fixes a race which can result in the same virtual IRQ number being assigned to two different MSI interrupts. The most visible consequence of that is usually a warning and stack trace from the sysfs code about an attempt to create a duplicate entry in sysfs. The race happens when one CPU (say CPU 0) is disposing of an MSI while another CPU (say CPU 1) is setting up an MSI. CPU 0 calls (for example) pnv_teardown_msi_irqs(), which calls msi_bitmap_free_hwirqs() to indicate that the MSI (i.e. its hardware IRQ number) is no longer in use. Then, before CPU 0 gets to calling irq_dispose_mapping() to free up the virtal IRQ number, CPU 1 comes in and calls msi_bitmap_alloc_hwirqs() to allocate an MSI, and gets the same hardware IRQ number that CPU 0 just freed. CPU 1 then calls irq_create_mapping() to get a virtual IRQ number, which sees that there is currently a mapping for that hardware IRQ number and returns the corresponding virtual IRQ number (which is the same virtual IRQ number that CPU 0 was using). CPU 0 then calls irq_dispose_mapping() and frees that virtual IRQ number. Now, if another CPU comes along and calls irq_create_mapping(), it is likely to get the virtual IRQ number that was just freed, resulting in the same virtual IRQ number apparently being used for two different hardware interrupts. To fix this race, we just move the call to msi_bitmap_free_hwirqs() to after the call to irq_dispose_mapping(). Since virq_to_hw() doesn't work for the virtual IRQ number after irq_dispose_mapping() has been called, we need to call it before irq_dispose_mapping() and remember the result for the msi_bitmap_free_hwirqs() call. The pattern of calling msi_bitmap_free_hwirqs() before irq_dispose_mapping() appears in 5 places under arch/powerpc, and appears to have originated in commit 05af7bd2d75e ("[POWERPC] MPIC U3/U4 MSI backend") from 2007. Fixes: 05af7bd2d75e ("[POWERPC] MPIC U3/U4 MSI backend") Cc: stable@vger.kernel.org # v2.6.22+ Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-09-10 07:36:21 +03:00
hwirq = virq_to_hw(entry->irq);
irq_set_msi_desc(entry->irq, NULL);
irq_dispose_mapping(entry->irq);
powerpc/MSI: Fix race condition in tearing down MSI interrupts This fixes a race which can result in the same virtual IRQ number being assigned to two different MSI interrupts. The most visible consequence of that is usually a warning and stack trace from the sysfs code about an attempt to create a duplicate entry in sysfs. The race happens when one CPU (say CPU 0) is disposing of an MSI while another CPU (say CPU 1) is setting up an MSI. CPU 0 calls (for example) pnv_teardown_msi_irqs(), which calls msi_bitmap_free_hwirqs() to indicate that the MSI (i.e. its hardware IRQ number) is no longer in use. Then, before CPU 0 gets to calling irq_dispose_mapping() to free up the virtal IRQ number, CPU 1 comes in and calls msi_bitmap_alloc_hwirqs() to allocate an MSI, and gets the same hardware IRQ number that CPU 0 just freed. CPU 1 then calls irq_create_mapping() to get a virtual IRQ number, which sees that there is currently a mapping for that hardware IRQ number and returns the corresponding virtual IRQ number (which is the same virtual IRQ number that CPU 0 was using). CPU 0 then calls irq_dispose_mapping() and frees that virtual IRQ number. Now, if another CPU comes along and calls irq_create_mapping(), it is likely to get the virtual IRQ number that was just freed, resulting in the same virtual IRQ number apparently being used for two different hardware interrupts. To fix this race, we just move the call to msi_bitmap_free_hwirqs() to after the call to irq_dispose_mapping(). Since virq_to_hw() doesn't work for the virtual IRQ number after irq_dispose_mapping() has been called, we need to call it before irq_dispose_mapping() and remember the result for the msi_bitmap_free_hwirqs() call. The pattern of calling msi_bitmap_free_hwirqs() before irq_dispose_mapping() appears in 5 places under arch/powerpc, and appears to have originated in commit 05af7bd2d75e ("[POWERPC] MPIC U3/U4 MSI backend") from 2007. Fixes: 05af7bd2d75e ("[POWERPC] MPIC U3/U4 MSI backend") Cc: stable@vger.kernel.org # v2.6.22+ Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-09-10 07:36:21 +03:00
msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq - phb->msi_base, 1);
}
}
/* Nicely print the contents of the PE State Tables (PEST). */
static void pnv_pci_dump_pest(__be64 pestA[], __be64 pestB[], int pest_size)
{
__be64 prevA = ULONG_MAX, prevB = ULONG_MAX;
bool dup = false;
int i;
for (i = 0; i < pest_size; i++) {
__be64 peA = be64_to_cpu(pestA[i]);
__be64 peB = be64_to_cpu(pestB[i]);
if (peA != prevA || peB != prevB) {
if (dup) {
pr_info("PE[..%03x] A/B: as above\n", i-1);
dup = false;
}
prevA = peA;
prevB = peB;
if (peA & PNV_IODA_STOPPED_STATE ||
peB & PNV_IODA_STOPPED_STATE)
pr_info("PE[%03x] A/B: %016llx %016llx\n",
i, peA, peB);
} else if (!dup && (peA & PNV_IODA_STOPPED_STATE ||
peB & PNV_IODA_STOPPED_STATE)) {
dup = true;
}
}
}
static void pnv_pci_dump_p7ioc_diag_data(struct pci_controller *hose,
struct OpalIoPhbErrorCommon *common)
{
struct OpalIoP7IOCPhbErrorData *data;
data = (struct OpalIoP7IOCPhbErrorData *)common;
pr_info("P7IOC PHB#%x Diag-data (Version: %d)\n",
hose->global_number, be32_to_cpu(common->version));
if (data->brdgCtl)
pr_info("brdgCtl: %08x\n",
be32_to_cpu(data->brdgCtl));
if (data->portStatusReg || data->rootCmplxStatus ||
data->busAgentStatus)
pr_info("UtlSts: %08x %08x %08x\n",
be32_to_cpu(data->portStatusReg),
be32_to_cpu(data->rootCmplxStatus),
be32_to_cpu(data->busAgentStatus));
if (data->deviceStatus || data->slotStatus ||
data->linkStatus || data->devCmdStatus ||
data->devSecStatus)
pr_info("RootSts: %08x %08x %08x %08x %08x\n",
be32_to_cpu(data->deviceStatus),
be32_to_cpu(data->slotStatus),
be32_to_cpu(data->linkStatus),
be32_to_cpu(data->devCmdStatus),
be32_to_cpu(data->devSecStatus));
if (data->rootErrorStatus || data->uncorrErrorStatus ||
data->corrErrorStatus)
pr_info("RootErrSts: %08x %08x %08x\n",
be32_to_cpu(data->rootErrorStatus),
be32_to_cpu(data->uncorrErrorStatus),
be32_to_cpu(data->corrErrorStatus));
if (data->tlpHdr1 || data->tlpHdr2 ||
data->tlpHdr3 || data->tlpHdr4)
pr_info("RootErrLog: %08x %08x %08x %08x\n",
be32_to_cpu(data->tlpHdr1),
be32_to_cpu(data->tlpHdr2),
be32_to_cpu(data->tlpHdr3),
be32_to_cpu(data->tlpHdr4));
if (data->sourceId || data->errorClass ||
data->correlator)
pr_info("RootErrLog1: %08x %016llx %016llx\n",
be32_to_cpu(data->sourceId),
be64_to_cpu(data->errorClass),
be64_to_cpu(data->correlator));
if (data->p7iocPlssr || data->p7iocCsr)
pr_info("PhbSts: %016llx %016llx\n",
be64_to_cpu(data->p7iocPlssr),
be64_to_cpu(data->p7iocCsr));
if (data->lemFir)
pr_info("Lem: %016llx %016llx %016llx\n",
be64_to_cpu(data->lemFir),
be64_to_cpu(data->lemErrorMask),
be64_to_cpu(data->lemWOF));
if (data->phbErrorStatus)
pr_info("PhbErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbErrorStatus),
be64_to_cpu(data->phbFirstErrorStatus),
be64_to_cpu(data->phbErrorLog0),
be64_to_cpu(data->phbErrorLog1));
if (data->mmioErrorStatus)
pr_info("OutErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->mmioErrorStatus),
be64_to_cpu(data->mmioFirstErrorStatus),
be64_to_cpu(data->mmioErrorLog0),
be64_to_cpu(data->mmioErrorLog1));
if (data->dma0ErrorStatus)
pr_info("InAErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->dma0ErrorStatus),
be64_to_cpu(data->dma0FirstErrorStatus),
be64_to_cpu(data->dma0ErrorLog0),
be64_to_cpu(data->dma0ErrorLog1));
if (data->dma1ErrorStatus)
pr_info("InBErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->dma1ErrorStatus),
be64_to_cpu(data->dma1FirstErrorStatus),
be64_to_cpu(data->dma1ErrorLog0),
be64_to_cpu(data->dma1ErrorLog1));
pnv_pci_dump_pest(data->pestA, data->pestB, OPAL_P7IOC_NUM_PEST_REGS);
}
static void pnv_pci_dump_phb3_diag_data(struct pci_controller *hose,
struct OpalIoPhbErrorCommon *common)
{
struct OpalIoPhb3ErrorData *data;
data = (struct OpalIoPhb3ErrorData*)common;
pr_info("PHB3 PHB#%x Diag-data (Version: %d)\n",
hose->global_number, be32_to_cpu(common->version));
if (data->brdgCtl)
pr_info("brdgCtl: %08x\n",
be32_to_cpu(data->brdgCtl));
if (data->portStatusReg || data->rootCmplxStatus ||
data->busAgentStatus)
pr_info("UtlSts: %08x %08x %08x\n",
be32_to_cpu(data->portStatusReg),
be32_to_cpu(data->rootCmplxStatus),
be32_to_cpu(data->busAgentStatus));
if (data->deviceStatus || data->slotStatus ||
data->linkStatus || data->devCmdStatus ||
data->devSecStatus)
pr_info("RootSts: %08x %08x %08x %08x %08x\n",
be32_to_cpu(data->deviceStatus),
be32_to_cpu(data->slotStatus),
be32_to_cpu(data->linkStatus),
be32_to_cpu(data->devCmdStatus),
be32_to_cpu(data->devSecStatus));
if (data->rootErrorStatus || data->uncorrErrorStatus ||
data->corrErrorStatus)
pr_info("RootErrSts: %08x %08x %08x\n",
be32_to_cpu(data->rootErrorStatus),
be32_to_cpu(data->uncorrErrorStatus),
be32_to_cpu(data->corrErrorStatus));
if (data->tlpHdr1 || data->tlpHdr2 ||
data->tlpHdr3 || data->tlpHdr4)
pr_info("RootErrLog: %08x %08x %08x %08x\n",
be32_to_cpu(data->tlpHdr1),
be32_to_cpu(data->tlpHdr2),
be32_to_cpu(data->tlpHdr3),
be32_to_cpu(data->tlpHdr4));
if (data->sourceId || data->errorClass ||
data->correlator)
pr_info("RootErrLog1: %08x %016llx %016llx\n",
be32_to_cpu(data->sourceId),
be64_to_cpu(data->errorClass),
be64_to_cpu(data->correlator));
if (data->nFir)
pr_info("nFir: %016llx %016llx %016llx\n",
be64_to_cpu(data->nFir),
be64_to_cpu(data->nFirMask),
be64_to_cpu(data->nFirWOF));
if (data->phbPlssr || data->phbCsr)
pr_info("PhbSts: %016llx %016llx\n",
be64_to_cpu(data->phbPlssr),
be64_to_cpu(data->phbCsr));
if (data->lemFir)
pr_info("Lem: %016llx %016llx %016llx\n",
be64_to_cpu(data->lemFir),
be64_to_cpu(data->lemErrorMask),
be64_to_cpu(data->lemWOF));
if (data->phbErrorStatus)
pr_info("PhbErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbErrorStatus),
be64_to_cpu(data->phbFirstErrorStatus),
be64_to_cpu(data->phbErrorLog0),
be64_to_cpu(data->phbErrorLog1));
if (data->mmioErrorStatus)
pr_info("OutErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->mmioErrorStatus),
be64_to_cpu(data->mmioFirstErrorStatus),
be64_to_cpu(data->mmioErrorLog0),
be64_to_cpu(data->mmioErrorLog1));
if (data->dma0ErrorStatus)
pr_info("InAErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->dma0ErrorStatus),
be64_to_cpu(data->dma0FirstErrorStatus),
be64_to_cpu(data->dma0ErrorLog0),
be64_to_cpu(data->dma0ErrorLog1));
if (data->dma1ErrorStatus)
pr_info("InBErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->dma1ErrorStatus),
be64_to_cpu(data->dma1FirstErrorStatus),
be64_to_cpu(data->dma1ErrorLog0),
be64_to_cpu(data->dma1ErrorLog1));
pnv_pci_dump_pest(data->pestA, data->pestB, OPAL_PHB3_NUM_PEST_REGS);
}
static void pnv_pci_dump_phb4_diag_data(struct pci_controller *hose,
struct OpalIoPhbErrorCommon *common)
{
struct OpalIoPhb4ErrorData *data;
data = (struct OpalIoPhb4ErrorData*)common;
pr_info("PHB4 PHB#%d Diag-data (Version: %d)\n",
hose->global_number, be32_to_cpu(common->version));
if (data->brdgCtl)
pr_info("brdgCtl: %08x\n",
be32_to_cpu(data->brdgCtl));
if (data->deviceStatus || data->slotStatus ||
data->linkStatus || data->devCmdStatus ||
data->devSecStatus)
pr_info("RootSts: %08x %08x %08x %08x %08x\n",
be32_to_cpu(data->deviceStatus),
be32_to_cpu(data->slotStatus),
be32_to_cpu(data->linkStatus),
be32_to_cpu(data->devCmdStatus),
be32_to_cpu(data->devSecStatus));
if (data->rootErrorStatus || data->uncorrErrorStatus ||
data->corrErrorStatus)
pr_info("RootErrSts: %08x %08x %08x\n",
be32_to_cpu(data->rootErrorStatus),
be32_to_cpu(data->uncorrErrorStatus),
be32_to_cpu(data->corrErrorStatus));
if (data->tlpHdr1 || data->tlpHdr2 ||
data->tlpHdr3 || data->tlpHdr4)
pr_info("RootErrLog: %08x %08x %08x %08x\n",
be32_to_cpu(data->tlpHdr1),
be32_to_cpu(data->tlpHdr2),
be32_to_cpu(data->tlpHdr3),
be32_to_cpu(data->tlpHdr4));
if (data->sourceId)
pr_info("sourceId: %08x\n", be32_to_cpu(data->sourceId));
if (data->nFir)
pr_info("nFir: %016llx %016llx %016llx\n",
be64_to_cpu(data->nFir),
be64_to_cpu(data->nFirMask),
be64_to_cpu(data->nFirWOF));
if (data->phbPlssr || data->phbCsr)
pr_info("PhbSts: %016llx %016llx\n",
be64_to_cpu(data->phbPlssr),
be64_to_cpu(data->phbCsr));
if (data->lemFir)
pr_info("Lem: %016llx %016llx %016llx\n",
be64_to_cpu(data->lemFir),
be64_to_cpu(data->lemErrorMask),
be64_to_cpu(data->lemWOF));
if (data->phbErrorStatus)
pr_info("PhbErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbErrorStatus),
be64_to_cpu(data->phbFirstErrorStatus),
be64_to_cpu(data->phbErrorLog0),
be64_to_cpu(data->phbErrorLog1));
if (data->phbTxeErrorStatus)
pr_info("PhbTxeErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbTxeErrorStatus),
be64_to_cpu(data->phbTxeFirstErrorStatus),
be64_to_cpu(data->phbTxeErrorLog0),
be64_to_cpu(data->phbTxeErrorLog1));
if (data->phbRxeArbErrorStatus)
pr_info("RxeArbErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbRxeArbErrorStatus),
be64_to_cpu(data->phbRxeArbFirstErrorStatus),
be64_to_cpu(data->phbRxeArbErrorLog0),
be64_to_cpu(data->phbRxeArbErrorLog1));
if (data->phbRxeMrgErrorStatus)
pr_info("RxeMrgErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbRxeMrgErrorStatus),
be64_to_cpu(data->phbRxeMrgFirstErrorStatus),
be64_to_cpu(data->phbRxeMrgErrorLog0),
be64_to_cpu(data->phbRxeMrgErrorLog1));
if (data->phbRxeTceErrorStatus)
pr_info("RxeTceErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbRxeTceErrorStatus),
be64_to_cpu(data->phbRxeTceFirstErrorStatus),
be64_to_cpu(data->phbRxeTceErrorLog0),
be64_to_cpu(data->phbRxeTceErrorLog1));
if (data->phbPblErrorStatus)
pr_info("PblErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbPblErrorStatus),
be64_to_cpu(data->phbPblFirstErrorStatus),
be64_to_cpu(data->phbPblErrorLog0),
be64_to_cpu(data->phbPblErrorLog1));
if (data->phbPcieDlpErrorStatus)
pr_info("PcieDlp: %016llx %016llx %016llx\n",
be64_to_cpu(data->phbPcieDlpErrorLog1),
be64_to_cpu(data->phbPcieDlpErrorLog2),
be64_to_cpu(data->phbPcieDlpErrorStatus));
if (data->phbRegbErrorStatus)
pr_info("RegbErr: %016llx %016llx %016llx %016llx\n",
be64_to_cpu(data->phbRegbErrorStatus),
be64_to_cpu(data->phbRegbFirstErrorStatus),
be64_to_cpu(data->phbRegbErrorLog0),
be64_to_cpu(data->phbRegbErrorLog1));
pnv_pci_dump_pest(data->pestA, data->pestB, OPAL_PHB4_NUM_PEST_REGS);
}
void pnv_pci_dump_phb_diag_data(struct pci_controller *hose,
unsigned char *log_buff)
{
struct OpalIoPhbErrorCommon *common;
if (!hose || !log_buff)
return;
common = (struct OpalIoPhbErrorCommon *)log_buff;
switch (be32_to_cpu(common->ioType)) {
case OPAL_PHB_ERROR_DATA_TYPE_P7IOC:
pnv_pci_dump_p7ioc_diag_data(hose, common);
break;
case OPAL_PHB_ERROR_DATA_TYPE_PHB3:
pnv_pci_dump_phb3_diag_data(hose, common);
break;
case OPAL_PHB_ERROR_DATA_TYPE_PHB4:
pnv_pci_dump_phb4_diag_data(hose, common);
break;
default:
pr_warn("%s: Unrecognized ioType %d\n",
__func__, be32_to_cpu(common->ioType));
}
}
static void pnv_pci_handle_eeh_config(struct pnv_phb *phb, u32 pe_no)
{
unsigned long flags, rc;
int has_diag, ret = 0;
spin_lock_irqsave(&phb->lock, flags);
/* Fetch PHB diag-data */
rc = opal_pci_get_phb_diag_data2(phb->opal_id, phb->diag_data,
phb->diag_data_size);
has_diag = (rc == OPAL_SUCCESS);
/* If PHB supports compound PE, to handle it */
if (phb->unfreeze_pe) {
ret = phb->unfreeze_pe(phb,
pe_no,
OPAL_EEH_ACTION_CLEAR_FREEZE_ALL);
} else {
rc = opal_pci_eeh_freeze_clear(phb->opal_id,
pe_no,
OPAL_EEH_ACTION_CLEAR_FREEZE_ALL);
if (rc) {
pr_warn("%s: Failure %ld clearing frozen "
"PHB#%x-PE#%x\n",
__func__, rc, phb->hose->global_number,
pe_no);
ret = -EIO;
}
}
/*
* For now, let's only display the diag buffer when we fail to clear
* the EEH status. We'll do more sensible things later when we have
* proper EEH support. We need to make sure we don't pollute ourselves
* with the normal errors generated when probing empty slots
*/
if (has_diag && ret)
pnv_pci_dump_phb_diag_data(phb->hose, phb->diag_data);
spin_unlock_irqrestore(&phb->lock, flags);
}
static void pnv_pci_config_check_eeh(struct pci_dn *pdn)
{
struct pnv_phb *phb = pdn->phb->private_data;
u8 fstate = 0;
__be16 pcierr = 0;
unsigned int pe_no;
s64 rc;
/*
* Get the PE#. During the PCI probe stage, we might not
* setup that yet. So all ER errors should be mapped to
* reserved PE.
*/
pe_no = pdn->pe_number;
if (pe_no == IODA_INVALID_PE) {
pe_no = phb->ioda.reserved_pe_idx;
}
/*
* Fetch frozen state. If the PHB support compound PE,
* we need handle that case.
*/
if (phb->get_pe_state) {
fstate = phb->get_pe_state(phb, pe_no);
} else {
rc = opal_pci_eeh_freeze_status(phb->opal_id,
pe_no,
&fstate,
&pcierr,
NULL);
if (rc) {
pr_warn("%s: Failure %lld getting PHB#%x-PE#%x state\n",
__func__, rc, phb->hose->global_number, pe_no);
return;
}
}
pr_devel(" -> EEH check, bdfn=%04x PE#%x fstate=%x\n",
(pdn->busno << 8) | (pdn->devfn), pe_no, fstate);
/* Clear the frozen state if applicable */
if (fstate == OPAL_EEH_STOPPED_MMIO_FREEZE ||
fstate == OPAL_EEH_STOPPED_DMA_FREEZE ||
fstate == OPAL_EEH_STOPPED_MMIO_DMA_FREEZE) {
/*
* If PHB supports compound PE, freeze it for
* consistency.
*/
if (phb->freeze_pe)
phb->freeze_pe(phb, pe_no);
pnv_pci_handle_eeh_config(phb, pe_no);
}
}
int pnv_pci_cfg_read(struct pci_dn *pdn,
int where, int size, u32 *val)
{
struct pnv_phb *phb = pdn->phb->private_data;
u32 bdfn = (pdn->busno << 8) | pdn->devfn;
s64 rc;
switch (size) {
case 1: {
u8 v8;
rc = opal_pci_config_read_byte(phb->opal_id, bdfn, where, &v8);
*val = (rc == OPAL_SUCCESS) ? v8 : 0xff;
break;
}
case 2: {
__be16 v16;
rc = opal_pci_config_read_half_word(phb->opal_id, bdfn, where,
&v16);
*val = (rc == OPAL_SUCCESS) ? be16_to_cpu(v16) : 0xffff;
break;
}
case 4: {
__be32 v32;
rc = opal_pci_config_read_word(phb->opal_id, bdfn, where, &v32);
*val = (rc == OPAL_SUCCESS) ? be32_to_cpu(v32) : 0xffffffff;
break;
}
default:
return PCIBIOS_FUNC_NOT_SUPPORTED;
}
pr_devel("%s: bus: %x devfn: %x +%x/%x -> %08x\n",
__func__, pdn->busno, pdn->devfn, where, size, *val);
return PCIBIOS_SUCCESSFUL;
}
int pnv_pci_cfg_write(struct pci_dn *pdn,
int where, int size, u32 val)
{
struct pnv_phb *phb = pdn->phb->private_data;
u32 bdfn = (pdn->busno << 8) | pdn->devfn;
pr_devel("%s: bus: %x devfn: %x +%x/%x -> %08x\n",
__func__, pdn->busno, pdn->devfn, where, size, val);
switch (size) {
case 1:
opal_pci_config_write_byte(phb->opal_id, bdfn, where, val);
break;
case 2:
opal_pci_config_write_half_word(phb->opal_id, bdfn, where, val);
break;
case 4:
opal_pci_config_write_word(phb->opal_id, bdfn, where, val);
break;
default:
return PCIBIOS_FUNC_NOT_SUPPORTED;
}
return PCIBIOS_SUCCESSFUL;
}
#if CONFIG_EEH
static bool pnv_pci_cfg_check(struct pci_dn *pdn)
{
struct eeh_dev *edev = NULL;
struct pnv_phb *phb = pdn->phb->private_data;
/* EEH not enabled ? */
if (!(phb->flags & PNV_PHB_FLAG_EEH))
return true;
2014-04-24 12:00:19 +04:00
/* PE reset or device removed ? */
edev = pdn->edev;
2014-04-24 12:00:19 +04:00
if (edev) {
if (edev->pe &&
(edev->pe->state & EEH_PE_CFG_BLOCKED))
2014-04-24 12:00:19 +04:00
return false;
if (edev->mode & EEH_DEV_REMOVED)
return false;
}
return true;
}
#else
static inline pnv_pci_cfg_check(struct pci_dn *pdn)
{
return true;
}
#endif /* CONFIG_EEH */
static int pnv_pci_read_config(struct pci_bus *bus,
unsigned int devfn,
int where, int size, u32 *val)
{
struct pci_dn *pdn;
struct pnv_phb *phb;
int ret;
*val = 0xFFFFFFFF;
pdn = pci_get_pdn_by_devfn(bus, devfn);
if (!pdn)
return PCIBIOS_DEVICE_NOT_FOUND;
if (!pnv_pci_cfg_check(pdn))
return PCIBIOS_DEVICE_NOT_FOUND;
ret = pnv_pci_cfg_read(pdn, where, size, val);
phb = pdn->phb->private_data;
if (phb->flags & PNV_PHB_FLAG_EEH && pdn->edev) {
if (*val == EEH_IO_ERROR_VALUE(size) &&
eeh_dev_check_failure(pdn->edev))
return PCIBIOS_DEVICE_NOT_FOUND;
} else {
pnv_pci_config_check_eeh(pdn);
}
return ret;
}
static int pnv_pci_write_config(struct pci_bus *bus,
unsigned int devfn,
int where, int size, u32 val)
{
struct pci_dn *pdn;
struct pnv_phb *phb;
int ret;
pdn = pci_get_pdn_by_devfn(bus, devfn);
if (!pdn)
return PCIBIOS_DEVICE_NOT_FOUND;
if (!pnv_pci_cfg_check(pdn))
return PCIBIOS_DEVICE_NOT_FOUND;
ret = pnv_pci_cfg_write(pdn, where, size, val);
phb = pdn->phb->private_data;
if (!(phb->flags & PNV_PHB_FLAG_EEH))
pnv_pci_config_check_eeh(pdn);
return ret;
}
struct pci_ops pnv_pci_ops = {
.read = pnv_pci_read_config,
.write = pnv_pci_write_config,
};
struct iommu_table *pnv_pci_table_alloc(int nid)
{
struct iommu_table *tbl;
tbl = kzalloc_node(sizeof(struct iommu_table), GFP_KERNEL, nid);
if (!tbl)
return NULL;
INIT_LIST_HEAD_RCU(&tbl->it_group_list);
kref_init(&tbl->it_kref);
return tbl;
}
void pnv_pci_dma_dev_setup(struct pci_dev *pdev)
{
struct pci_controller *hose = pci_bus_to_host(pdev->bus);
struct pnv_phb *phb = hose->private_data;
#ifdef CONFIG_PCI_IOV
struct pnv_ioda_pe *pe;
struct pci_dn *pdn;
/* Fix the VF pdn PE number */
if (pdev->is_virtfn) {
pdn = pci_get_pdn(pdev);
WARN_ON(pdn->pe_number != IODA_INVALID_PE);
list_for_each_entry(pe, &phb->ioda.pe_list, list) {
if (pe->rid == ((pdev->bus->number << 8) |
(pdev->devfn & 0xff))) {
pdn->pe_number = pe->pe_number;
pe->pdev = pdev;
break;
}
}
}
#endif /* CONFIG_PCI_IOV */
if (phb && phb->dma_dev_setup)
phb->dma_dev_setup(phb, pdev);
}
void pnv_pci_dma_bus_setup(struct pci_bus *bus)
{
struct pci_controller *hose = bus->sysdata;
struct pnv_phb *phb = hose->private_data;
struct pnv_ioda_pe *pe;
list_for_each_entry(pe, &phb->ioda.pe_list, list) {
if (!(pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL)))
continue;
if (!pe->pbus)
continue;
if (bus->number == ((pe->rid >> 8) & 0xFF)) {
pe->pbus = bus;
break;
}
}
}
struct device_node *pnv_pci_get_phb_node(struct pci_dev *dev)
{
struct pci_controller *hose = pci_bus_to_host(dev->bus);
return of_node_get(hose->dn);
}
EXPORT_SYMBOL(pnv_pci_get_phb_node);
int pnv_pci_set_tunnel_bar(struct pci_dev *dev, u64 addr, int enable)
{
__be64 val;
struct pci_controller *hose;
struct pnv_phb *phb;
u64 tunnel_bar;
int rc;
if (!opal_check_token(OPAL_PCI_GET_PBCQ_TUNNEL_BAR))
return -ENXIO;
if (!opal_check_token(OPAL_PCI_SET_PBCQ_TUNNEL_BAR))
return -ENXIO;
hose = pci_bus_to_host(dev->bus);
phb = hose->private_data;
mutex_lock(&tunnel_mutex);
rc = opal_pci_get_pbcq_tunnel_bar(phb->opal_id, &val);
if (rc != OPAL_SUCCESS) {
rc = -EIO;
goto out;
}
tunnel_bar = be64_to_cpu(val);
if (enable) {
/*
* Only one device per PHB can use atomics.
* Our policy is first-come, first-served.
*/
if (tunnel_bar) {
if (tunnel_bar != addr)
rc = -EBUSY;
else
rc = 0; /* Setting same address twice is ok */
goto out;
}
} else {
/*
* The device that owns atomics and wants to release
* them must pass the same address with enable == 0.
*/
if (tunnel_bar != addr) {
rc = -EPERM;
goto out;
}
addr = 0x0ULL;
}
rc = opal_pci_set_pbcq_tunnel_bar(phb->opal_id, addr);
rc = opal_error_code(rc);
out:
mutex_unlock(&tunnel_mutex);
return rc;
}
EXPORT_SYMBOL_GPL(pnv_pci_set_tunnel_bar);
void pnv_pci_shutdown(void)
{
struct pci_controller *hose;
list_for_each_entry(hose, &hose_list, list_node)
if (hose->controller_ops.shutdown)
hose->controller_ops.shutdown(hose);
}
/* Fixup wrong class code in p7ioc and p8 root complex */
static void pnv_p7ioc_rc_quirk(struct pci_dev *dev)
{
dev->class = PCI_CLASS_BRIDGE_PCI << 8;
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_IBM, 0x3b9, pnv_p7ioc_rc_quirk);
void __init pnv_pci_init(void)
{
struct device_node *np;
pci_add_flags(PCI_CAN_SKIP_ISA_ALIGN);
/* If we don't have OPAL, eg. in sim, just skip PCI probe */
if (!firmware_has_feature(FW_FEATURE_OPAL))
return;
/* Look for IODA IO-Hubs. */
for_each_compatible_node(np, NULL, "ibm,ioda-hub") {
pnv_pci_init_ioda_hub(np);
}
/* Look for ioda2 built-in PHB3's */
for_each_compatible_node(np, NULL, "ibm,ioda2-phb")
pnv_pci_init_ioda2_phb(np);
/* Look for ioda3 built-in PHB4's, we treat them as IODA2 */
for_each_compatible_node(np, NULL, "ibm,ioda3-phb")
pnv_pci_init_ioda2_phb(np);
/* Look for NPU PHBs */
for_each_compatible_node(np, NULL, "ibm,ioda2-npu-phb")
pnv_pci_init_npu_phb(np);
/*
* Look for NPU2 PHBs which we treat mostly as NPU PHBs with
* the exception of TCE kill which requires an OPAL call.
*/
for_each_compatible_node(np, NULL, "ibm,ioda2-npu2-phb")
pnv_pci_init_npu_phb(np);
/* Look for NPU2 OpenCAPI PHBs */
for_each_compatible_node(np, NULL, "ibm,ioda2-npu2-opencapi-phb")
pnv_pci_init_npu2_opencapi_phb(np);
/* Configure IOMMU DMA hooks */
set_pci_dma_ops(&dma_iommu_ops);
}
powerpc/powernv/pseries: Rework device adding to IOMMU groups The powernv platform registers IOMMU groups and adds devices to them from the pci_controller_ops::setup_bridge() hook except one case when virtual functions (SRIOV VFs) are added from a bus notifier. The pseries platform registers IOMMU groups from the pci_controller_ops::dma_bus_setup() hook and adds devices from the pci_controller_ops::dma_dev_setup() hook. The very same bus notifier used for powernv does not add devices for pseries though as __of_scan_bus() adds devices first, then it does the bus/dev DMA setup. Both platforms use iommu_add_device() which takes a device and expects it to have a valid IOMMU table struct with an iommu_table_group pointer which in turn points the iommu_group struct (which represents an IOMMU group). Although the helper seems easy to use, it relies on some pre-existing device configuration and associated data structures which it does not really need. This simplifies iommu_add_device() to take the table_group pointer directly. Pseries already has a table_group pointer handy and the bus notified is not used anyway. For powernv, this copies the existing bus notifier, makes it work for powernv only which means an easy way of getting to the table_group pointer. This was tested on VFs but should also support physical PCI hotplug. Since iommu_add_device() receives the table_group pointer directly, pseries does not do TCE cache invalidation (the hypervisor does) nor allow multiple groups per a VFIO container (in other words sharing an IOMMU table between partitionable endpoints), this removes iommu_table_group_link from pseries. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 11:52:21 +03:00
static int pnv_tce_iommu_bus_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
struct pci_dev *pdev;
struct pci_dn *pdn;
struct pnv_ioda_pe *pe;
struct pci_controller *hose;
struct pnv_phb *phb;
switch (action) {
case BUS_NOTIFY_ADD_DEVICE:
pdev = to_pci_dev(dev);
pdn = pci_get_pdn(pdev);
hose = pci_bus_to_host(pdev->bus);
phb = hose->private_data;
WARN_ON_ONCE(!phb);
if (!pdn || pdn->pe_number == IODA_INVALID_PE || !phb)
return 0;
pe = &phb->ioda.pe_array[pdn->pe_number];
powerpc/powernv/sriov: Register IOMMU groups for VFs The compound IOMMU group rework moved iommu_register_group() together in pnv_pci_ioda_setup_iommu_api() (which is a part of ppc_md.pcibios_fixup). As the result, pnv_ioda_setup_bus_iommu_group() does not create groups any more, it only adds devices to groups. This works fine for boot time devices. However IOMMU groups for SRIOV's VFs were added by pnv_ioda_setup_bus_iommu_group() so this got broken: pnv_tce_iommu_bus_notifier() expects a group to be registered for VF and it is not. This adds missing group registration and adds a NULL pointer check into the bus notifier so we won't crash if there is no group, although it is not expected to happen now because of the change above. Example oops seen prior to this patch: $ echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/sriov_numvfs Unable to handle kernel paging request for data at address 0x00000030 Faulting instruction address: 0xc0000000004a6018 Oops: Kernel access of bad area, sig: 11 [#1] LE SMP NR_CPUS=2048 NUMA PowerNV CPU: 46 PID: 7006 Comm: bash Not tainted 4.15-ish NIP: c0000000004a6018 LR: c0000000004a6014 CTR: 0000000000000000 REGS: c000008fc876b400 TRAP: 0300 Not tainted (4.15-ish) MSR: 900000000280b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CFAR: c000000000d0be20 DAR: 0000000000000030 DSISR: 40000000 SOFTE: 1 ... NIP sysfs_do_create_link_sd.isra.0+0x68/0x150 LR sysfs_do_create_link_sd.isra.0+0x64/0x150 Call Trace: pci_dev_type+0x0/0x30 (unreliable) iommu_group_add_device+0x8c/0x600 iommu_add_device+0xe8/0x180 pnv_tce_iommu_bus_notifier+0xb0/0xf0 notifier_call_chain+0x9c/0x110 blocking_notifier_call_chain+0x64/0xa0 device_add+0x524/0x7d0 pci_device_add+0x248/0x450 pci_iov_add_virtfn+0x294/0x3e0 pci_enable_sriov+0x43c/0x580 mlx5_core_sriov_configure+0x15c/0x2f0 [mlx5_core] sriov_numvfs_store+0x180/0x240 dev_attr_store+0x3c/0x60 sysfs_kf_write+0x64/0x90 kernfs_fop_write+0x1ac/0x240 __vfs_write+0x3c/0x70 vfs_write+0xd8/0x220 SyS_write+0x6c/0x110 system_call+0x58/0x6c Fixes: 0bd971676e68 ("powerpc/powernv/npu: Add compound IOMMU groups") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reported-by: Santwana Samantray <santwana.samantray@in.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18 08:58:01 +03:00
if (!pe->table_group.group)
return 0;
powerpc/powernv/pseries: Rework device adding to IOMMU groups The powernv platform registers IOMMU groups and adds devices to them from the pci_controller_ops::setup_bridge() hook except one case when virtual functions (SRIOV VFs) are added from a bus notifier. The pseries platform registers IOMMU groups from the pci_controller_ops::dma_bus_setup() hook and adds devices from the pci_controller_ops::dma_dev_setup() hook. The very same bus notifier used for powernv does not add devices for pseries though as __of_scan_bus() adds devices first, then it does the bus/dev DMA setup. Both platforms use iommu_add_device() which takes a device and expects it to have a valid IOMMU table struct with an iommu_table_group pointer which in turn points the iommu_group struct (which represents an IOMMU group). Although the helper seems easy to use, it relies on some pre-existing device configuration and associated data structures which it does not really need. This simplifies iommu_add_device() to take the table_group pointer directly. Pseries already has a table_group pointer handy and the bus notified is not used anyway. For powernv, this copies the existing bus notifier, makes it work for powernv only which means an easy way of getting to the table_group pointer. This was tested on VFs but should also support physical PCI hotplug. Since iommu_add_device() receives the table_group pointer directly, pseries does not do TCE cache invalidation (the hypervisor does) nor allow multiple groups per a VFIO container (in other words sharing an IOMMU table between partitionable endpoints), this removes iommu_table_group_link from pseries. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 11:52:21 +03:00
iommu_add_device(&pe->table_group, dev);
return 0;
case BUS_NOTIFY_DEL_DEVICE:
iommu_del_device(dev);
return 0;
default:
return 0;
}
}
static struct notifier_block pnv_tce_iommu_bus_nb = {
.notifier_call = pnv_tce_iommu_bus_notifier,
};
static int __init pnv_tce_iommu_bus_notifier_init(void)
{
bus_register_notifier(&pci_bus_type, &pnv_tce_iommu_bus_nb);
return 0;
}
machine_subsys_initcall_sync(powernv, pnv_tce_iommu_bus_notifier_init);