blob: 85bb66d7f93354edcf09e342cabe5438885b4a82 [file] [log] [blame]
/*
* Support PCI/PCIe on PowerNV platforms
*
* Currently supports only P5IOC2
*
* Copyright 2011 Benjamin Herrenschmidt, IBM Corp.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/msi.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/machdep.h>
#include <asm/ppc-pci.h>
#include <asm/opal.h>
#include <asm/iommu.h>
#include <asm/tce.h>
#include <asm/abs_addr.h>
#include "powernv.h"
#include "pci.h"
/* Delay in usec */
#define PCI_RESET_DELAY_US 3000000
#define cfg_dbg(fmt...) do { } while(0)
//#define cfg_dbg(fmt...) printk(fmt)
#ifdef CONFIG_PCI_MSI
static int pnv_msi_check_device(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;
return (phb && phb->msi_map) ? 0 : -ENODEV;
}
static unsigned int pnv_get_one_msi(struct pnv_phb *phb)
{
unsigned int id;
spin_lock(&phb->lock);
id = find_next_zero_bit(phb->msi_map, phb->msi_count, phb->msi_next);
if (id >= phb->msi_count && phb->msi_next)
id = find_next_zero_bit(phb->msi_map, phb->msi_count, 0);
if (id >= phb->msi_count) {
spin_unlock(&phb->lock);
return 0;
}
__set_bit(id, phb->msi_map);
spin_unlock(&phb->lock);
return id + phb->msi_base;
}
static void pnv_put_msi(struct pnv_phb *phb, unsigned int hwirq)
{
unsigned int id;
if (WARN_ON(hwirq < phb->msi_base ||
hwirq >= (phb->msi_base + phb->msi_count)))
return;
id = hwirq - phb->msi_base;
spin_lock(&phb->lock);
__clear_bit(id, phb->msi_map);
spin_unlock(&phb->lock);
}
static 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;
unsigned int hwirq, virq;
int rc;
if (WARN_ON(!phb))
return -ENODEV;
list_for_each_entry(entry, &pdev->msi_list, list) {
if (!entry->msi_attrib.is_64 && !phb->msi32_support) {
pr_warn("%s: Supports only 64-bit MSIs\n",
pci_name(pdev));
return -ENXIO;
}
hwirq = pnv_get_one_msi(phb);
if (!hwirq) {
pr_warn("%s: Failed to find a free MSI\n",
pci_name(pdev));
return -ENOSPC;
}
virq = irq_create_mapping(NULL, hwirq);
if (virq == NO_IRQ) {
pr_warn("%s: Failed to map MSI to linux irq\n",
pci_name(pdev));
pnv_put_msi(phb, hwirq);
return -ENOMEM;
}
rc = phb->msi_setup(phb, pdev, hwirq, entry->msi_attrib.is_64,
&msg);
if (rc) {
pr_warn("%s: Failed to setup MSI\n", pci_name(pdev));
irq_dispose_mapping(virq);
pnv_put_msi(phb, hwirq);
return rc;
}
irq_set_msi_desc(virq, entry);
write_msi_msg(virq, &msg);
}
return 0;
}
static 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;
if (WARN_ON(!phb))
return;
list_for_each_entry(entry, &pdev->msi_list, list) {
if (entry->irq == NO_IRQ)
continue;
irq_set_msi_desc(entry->irq, NULL);
pnv_put_msi(phb, virq_to_hw(entry->irq));
irq_dispose_mapping(entry->irq);
}
}
#endif /* CONFIG_PCI_MSI */
static void pnv_pci_config_check_eeh(struct pnv_phb *phb, struct pci_bus *bus,
u32 bdfn)
{
s64 rc;
u8 fstate;
u16 pcierr;
u32 pe_no;
/* Get PE# if we support IODA */
pe_no = phb->bdfn_to_pe ? phb->bdfn_to_pe(phb, bus, bdfn & 0xff) : 0;
/* Read freeze status */
rc = opal_pci_eeh_freeze_status(phb->opal_id, pe_no, &fstate, &pcierr,
NULL);
if (rc) {
pr_warning("PCI %d: Failed to read EEH status for PE#%d,"
" err %lld\n", phb->hose->global_number, pe_no, rc);
return;
}
cfg_dbg(" -> EEH check, bdfn=%04x PE%d fstate=%x\n",
bdfn, pe_no, fstate);
if (fstate != 0) {
rc = opal_pci_eeh_freeze_clear(phb->opal_id, pe_no,
OPAL_EEH_ACTION_CLEAR_FREEZE_ALL);
if (rc) {
pr_warning("PCI %d: Failed to clear EEH freeze state"
" for PE#%d, err %lld\n",
phb->hose->global_number, pe_no, rc);
}
}
}
static int pnv_pci_read_config(struct pci_bus *bus,
unsigned int devfn,
int where, int size, u32 *val)
{
struct pci_controller *hose = pci_bus_to_host(bus);
struct pnv_phb *phb = hose->private_data;
u32 bdfn = (((uint64_t)bus->number) << 8) | devfn;
s64 rc;
if (hose == NULL)
return PCIBIOS_DEVICE_NOT_FOUND;
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: {
u16 v16;
rc = opal_pci_config_read_half_word(phb->opal_id, bdfn, where,
&v16);
*val = (rc == OPAL_SUCCESS) ? v16 : 0xffff;
break;
}
case 4: {
u32 v32;
rc = opal_pci_config_read_word(phb->opal_id, bdfn, where, &v32);
*val = (rc == OPAL_SUCCESS) ? v32 : 0xffffffff;
break;
}
default:
return PCIBIOS_FUNC_NOT_SUPPORTED;
}
cfg_dbg("pnv_pci_read_config bus: %x devfn: %x +%x/%x -> %08x\n",
bus->number, devfn, where, size, *val);
/* Check if the PHB got frozen due to an error (no response) */
pnv_pci_config_check_eeh(phb, bus, bdfn);
return PCIBIOS_SUCCESSFUL;
}
static int pnv_pci_write_config(struct pci_bus *bus,
unsigned int devfn,
int where, int size, u32 val)
{
struct pci_controller *hose = pci_bus_to_host(bus);
struct pnv_phb *phb = hose->private_data;
u32 bdfn = (((uint64_t)bus->number) << 8) | devfn;
if (hose == NULL)
return PCIBIOS_DEVICE_NOT_FOUND;
cfg_dbg("pnv_pci_write_config bus: %x devfn: %x +%x/%x -> %08x\n",
bus->number, 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;
}
/* Check if the PHB got frozen due to an error (no response) */
pnv_pci_config_check_eeh(phb, bus, bdfn);
return PCIBIOS_SUCCESSFUL;
}
struct pci_ops pnv_pci_ops = {
.read = pnv_pci_read_config,
.write = pnv_pci_write_config,
};
static int pnv_tce_build(struct iommu_table *tbl, long index, long npages,
unsigned long uaddr, enum dma_data_direction direction,
struct dma_attrs *attrs)
{
u64 proto_tce;
u64 *tcep;
u64 rpn;
proto_tce = TCE_PCI_READ; // Read allowed
if (direction != DMA_TO_DEVICE)
proto_tce |= TCE_PCI_WRITE;
tcep = ((u64 *)tbl->it_base) + index;
while (npages--) {
/* can't move this out since we might cross LMB boundary */
rpn = (virt_to_abs(uaddr)) >> TCE_SHIFT;
*tcep = proto_tce | (rpn & TCE_RPN_MASK) << TCE_RPN_SHIFT;
uaddr += TCE_PAGE_SIZE;
tcep++;
}
return 0;
}
static void pnv_tce_free(struct iommu_table *tbl, long index, long npages)
{
u64 *tcep = ((u64 *)tbl->it_base) + index;
while (npages--)
*(tcep++) = 0;
}
void pnv_pci_setup_iommu_table(struct iommu_table *tbl,
void *tce_mem, u64 tce_size,
u64 dma_offset)
{
tbl->it_blocksize = 16;
tbl->it_base = (unsigned long)tce_mem;
tbl->it_offset = dma_offset >> IOMMU_PAGE_SHIFT;
tbl->it_index = 0;
tbl->it_size = tce_size >> 3;
tbl->it_busno = 0;
tbl->it_type = TCE_PCI;
}
static struct iommu_table * __devinit
pnv_pci_setup_bml_iommu(struct pci_controller *hose)
{
struct iommu_table *tbl;
const __be64 *basep;
const __be32 *sizep;
basep = of_get_property(hose->dn, "linux,tce-base", NULL);
sizep = of_get_property(hose->dn, "linux,tce-size", NULL);
if (basep == NULL || sizep == NULL) {
pr_err("PCI: %s has missing tce entries !\n", hose->dn->full_name);
return NULL;
}
tbl = kzalloc_node(sizeof(struct iommu_table), GFP_KERNEL, hose->node);
if (WARN_ON(!tbl))
return NULL;
pnv_pci_setup_iommu_table(tbl, __va(be64_to_cpup(basep)),
be32_to_cpup(sizep), 0);
iommu_init_table(tbl, hose->node);
return tbl;
}
static void __devinit pnv_pci_dma_fallback_setup(struct pci_controller *hose,
struct pci_dev *pdev)
{
struct device_node *np = pci_bus_to_OF_node(hose->bus);
struct pci_dn *pdn;
if (np == NULL)
return;
pdn = PCI_DN(np);
if (!pdn->iommu_table)
pdn->iommu_table = pnv_pci_setup_bml_iommu(hose);
if (!pdn->iommu_table)
return;
set_iommu_table_base(&pdev->dev, pdn->iommu_table);
}
static void __devinit 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;
/* If we have no phb structure, try to setup a fallback based on
* the device-tree (RTAS PCI for example)
*/
if (phb && phb->dma_dev_setup)
phb->dma_dev_setup(phb, pdev);
else
pnv_pci_dma_fallback_setup(hose, pdev);
}
static int pnv_pci_probe_mode(struct pci_bus *bus)
{
struct pci_controller *hose = pci_bus_to_host(bus);
const __be64 *tstamp;
u64 now, target;
/* We hijack this as a way to ensure we have waited long
* enough since the reset was lifted on the PCI bus
*/
if (bus != hose->bus)
return PCI_PROBE_NORMAL;
tstamp = of_get_property(hose->dn, "reset-clear-timestamp", NULL);
if (!tstamp || !*tstamp)
return PCI_PROBE_NORMAL;
now = mftb() / tb_ticks_per_usec;
target = (be64_to_cpup(tstamp) / tb_ticks_per_usec)
+ PCI_RESET_DELAY_US;
pr_devel("pci %04d: Reset target: 0x%llx now: 0x%llx\n",
hose->global_number, target, now);
if (now < target)
msleep((target - now + 999) / 1000);
return PCI_PROBE_NORMAL;
}
void __init pnv_pci_init(void)
{
struct device_node *np;
pci_set_flags(PCI_CAN_SKIP_ISA_ALIGN);
/* We do not want to just probe */
pci_probe_only = 0;
/* OPAL absent, try POPAL first then RTAS detection of PHBs */
if (!firmware_has_feature(FW_FEATURE_OPAL)) {
#ifdef CONFIG_PPC_POWERNV_RTAS
init_pci_config_tokens();
find_and_init_phbs();
#endif /* CONFIG_PPC_POWERNV_RTAS */
} else {
/* OPAL is here, do our normal stuff */
/* Look for p5ioc2 IO-Hubs */
for_each_compatible_node(np, NULL, "ibm,p5ioc2")
pnv_pci_init_p5ioc2_hub(np);
}
/* Setup the linkage between OF nodes and PHBs */
pci_devs_phb_init();
/* Configure IOMMU DMA hooks */
ppc_md.pci_dma_dev_setup = pnv_pci_dma_dev_setup;
ppc_md.tce_build = pnv_tce_build;
ppc_md.tce_free = pnv_tce_free;
ppc_md.pci_probe_mode = pnv_pci_probe_mode;
set_pci_dma_ops(&dma_iommu_ops);
/* Configure MSIs */
#ifdef CONFIG_PCI_MSI
ppc_md.msi_check_device = pnv_msi_check_device;
ppc_md.setup_msi_irqs = pnv_setup_msi_irqs;
ppc_md.teardown_msi_irqs = pnv_teardown_msi_irqs;
#endif
}