blob: 1264253cc07bc749845af3bf8d925ce43e31c772 [file] [log] [blame] [edit]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2014 IBM Corp.
*/
#include <linux/pci.h>
#include <misc/cxl.h>
#include "cxl.h"
static int cxl_pci_probe_mode(struct pci_bus *bus)
{
return PCI_PROBE_NORMAL;
}
static int cxl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
{
return -ENODEV;
}
static void cxl_teardown_msi_irqs(struct pci_dev *pdev)
{
/*
* MSI should never be set but need still need to provide this call
* back.
*/
}
static bool cxl_pci_enable_device_hook(struct pci_dev *dev)
{
struct pci_controller *phb;
struct cxl_afu *afu;
struct cxl_context *ctx;
phb = pci_bus_to_host(dev->bus);
afu = (struct cxl_afu *)phb->private_data;
if (!cxl_ops->link_ok(afu->adapter, afu)) {
dev_warn(&dev->dev, "%s: Device link is down, refusing to enable AFU\n", __func__);
return false;
}
dev->dev.archdata.dma_offset = PAGE_OFFSET;
/*
* Allocate a context to do cxl things too. If we eventually do real
* DMA ops, we'll need a default context to attach them to
*/
ctx = cxl_dev_context_init(dev);
if (IS_ERR(ctx))
return false;
dev->dev.archdata.cxl_ctx = ctx;
return (cxl_ops->afu_check_and_enable(afu) == 0);
}
static void cxl_pci_disable_device(struct pci_dev *dev)
{
struct cxl_context *ctx = cxl_get_context(dev);
if (ctx) {
if (ctx->status == STARTED) {
dev_err(&dev->dev, "Default context started\n");
return;
}
dev->dev.archdata.cxl_ctx = NULL;
cxl_release_context(ctx);
}
}
static resource_size_t cxl_pci_window_alignment(struct pci_bus *bus,
unsigned long type)
{
return 1;
}
static void cxl_pci_reset_secondary_bus(struct pci_dev *dev)
{
/* Should we do an AFU reset here ? */
}
static int cxl_pcie_cfg_record(u8 bus, u8 devfn)
{
return (bus << 8) + devfn;
}
static inline struct cxl_afu *pci_bus_to_afu(struct pci_bus *bus)
{
struct pci_controller *phb = bus ? pci_bus_to_host(bus) : NULL;
return phb ? phb->private_data : NULL;
}
static void cxl_afu_configured_put(struct cxl_afu *afu)
{
atomic_dec_if_positive(&afu->configured_state);
}
static bool cxl_afu_configured_get(struct cxl_afu *afu)
{
return atomic_inc_unless_negative(&afu->configured_state);
}
static inline int cxl_pcie_config_info(struct pci_bus *bus, unsigned int devfn,
struct cxl_afu *afu, int *_record)
{
int record;
record = cxl_pcie_cfg_record(bus->number, devfn);
if (record > afu->crs_num)
return PCIBIOS_DEVICE_NOT_FOUND;
*_record = record;
return 0;
}
static int cxl_pcie_read_config(struct pci_bus *bus, unsigned int devfn,
int offset, int len, u32 *val)
{
int rc, record;
struct cxl_afu *afu;
u8 val8;
u16 val16;
u32 val32;
afu = pci_bus_to_afu(bus);
/* Grab a reader lock on afu. */
if (afu == NULL || !cxl_afu_configured_get(afu))
return PCIBIOS_DEVICE_NOT_FOUND;
rc = cxl_pcie_config_info(bus, devfn, afu, &record);
if (rc)
goto out;
switch (len) {
case 1:
rc = cxl_ops->afu_cr_read8(afu, record, offset, &val8);
*val = val8;
break;
case 2:
rc = cxl_ops->afu_cr_read16(afu, record, offset, &val16);
*val = val16;
break;
case 4:
rc = cxl_ops->afu_cr_read32(afu, record, offset, &val32);
*val = val32;
break;
default:
WARN_ON(1);
}
out:
cxl_afu_configured_put(afu);
return rc ? PCIBIOS_DEVICE_NOT_FOUND : 0;
}
static int cxl_pcie_write_config(struct pci_bus *bus, unsigned int devfn,
int offset, int len, u32 val)
{
int rc, record;
struct cxl_afu *afu;
afu = pci_bus_to_afu(bus);
/* Grab a reader lock on afu. */
if (afu == NULL || !cxl_afu_configured_get(afu))
return PCIBIOS_DEVICE_NOT_FOUND;
rc = cxl_pcie_config_info(bus, devfn, afu, &record);
if (rc)
goto out;
switch (len) {
case 1:
rc = cxl_ops->afu_cr_write8(afu, record, offset, val & 0xff);
break;
case 2:
rc = cxl_ops->afu_cr_write16(afu, record, offset, val & 0xffff);
break;
case 4:
rc = cxl_ops->afu_cr_write32(afu, record, offset, val);
break;
default:
WARN_ON(1);
}
out:
cxl_afu_configured_put(afu);
return rc ? PCIBIOS_SET_FAILED : 0;
}
static struct pci_ops cxl_pcie_pci_ops =
{
.read = cxl_pcie_read_config,
.write = cxl_pcie_write_config,
};
static struct pci_controller_ops cxl_pci_controller_ops =
{
.probe_mode = cxl_pci_probe_mode,
.enable_device_hook = cxl_pci_enable_device_hook,
.disable_device = cxl_pci_disable_device,
.release_device = cxl_pci_disable_device,
.window_alignment = cxl_pci_window_alignment,
.reset_secondary_bus = cxl_pci_reset_secondary_bus,
.setup_msi_irqs = cxl_setup_msi_irqs,
.teardown_msi_irqs = cxl_teardown_msi_irqs,
};
int cxl_pci_vphb_add(struct cxl_afu *afu)
{
struct pci_controller *phb;
struct device_node *vphb_dn;
struct device *parent;
/*
* If there are no AFU configuration records we won't have anything to
* expose under the vPHB, so skip creating one, returning success since
* this is still a valid case. This will also opt us out of EEH
* handling since we won't have anything special to do if there are no
* kernel drivers attached to the vPHB, and EEH handling is not yet
* supported in the peer model.
*/
if (!afu->crs_num)
return 0;
/* The parent device is the adapter. Reuse the device node of
* the adapter.
* We don't seem to care what device node is used for the vPHB,
* but tools such as lsvpd walk up the device parents looking
* for a valid location code, so we might as well show devices
* attached to the adapter as being located on that adapter.
*/
parent = afu->adapter->dev.parent;
vphb_dn = parent->of_node;
/* Alloc and setup PHB data structure */
phb = pcibios_alloc_controller(vphb_dn);
if (!phb)
return -ENODEV;
/* Setup parent in sysfs */
phb->parent = parent;
/* Setup the PHB using arch provided callback */
phb->ops = &cxl_pcie_pci_ops;
phb->cfg_addr = NULL;
phb->cfg_data = NULL;
phb->private_data = afu;
phb->controller_ops = cxl_pci_controller_ops;
/* Scan the bus */
pcibios_scan_phb(phb);
if (phb->bus == NULL)
return -ENXIO;
/* Set release hook on root bus */
pci_set_host_bridge_release(to_pci_host_bridge(phb->bus->bridge),
pcibios_free_controller_deferred,
(void *) phb);
/* Claim resources. This might need some rework as well depending
* whether we are doing probe-only or not, like assigning unassigned
* resources etc...
*/
pcibios_claim_one_bus(phb->bus);
/* Add probed PCI devices to the device model */
pci_bus_add_devices(phb->bus);
afu->phb = phb;
return 0;
}
void cxl_pci_vphb_remove(struct cxl_afu *afu)
{
struct pci_controller *phb;
/* If there is no configuration record we won't have one of these */
if (!afu || !afu->phb)
return;
phb = afu->phb;
afu->phb = NULL;
pci_remove_root_bus(phb->bus);
/*
* We don't free phb here - that's handled by
* pcibios_free_controller_deferred()
*/
}
bool cxl_pci_is_vphb_device(struct pci_dev *dev)
{
struct pci_controller *phb;
phb = pci_bus_to_host(dev->bus);
return (phb->ops == &cxl_pcie_pci_ops);
}
struct cxl_afu *cxl_pci_to_afu(struct pci_dev *dev)
{
struct pci_controller *phb;
phb = pci_bus_to_host(dev->bus);
return (struct cxl_afu *)phb->private_data;
}
EXPORT_SYMBOL_GPL(cxl_pci_to_afu);
unsigned int cxl_pci_to_cfg_record(struct pci_dev *dev)
{
return cxl_pcie_cfg_record(dev->bus->number, dev->devfn);
}
EXPORT_SYMBOL_GPL(cxl_pci_to_cfg_record);