forked from Minki/linux
b72c1f6514
This moves the quirk itself to pci_64.c as to get built on all ppc64 platforms (the only ones with a pci_dn), factors the two implementations of get_pdn() into a single pci_get_dn() and use the quirk to do 32-bit MSIs on IODA based powernv platforms. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
501 lines
11 KiB
C
501 lines
11 KiB
C
/*
|
|
* Copyright 2006 Jake Moilanen <moilanen@austin.ibm.com>, IBM Corp.
|
|
* Copyright 2006-2007 Michael Ellerman, 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; version 2 of the
|
|
* License.
|
|
*
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/msi.h>
|
|
|
|
#include <asm/rtas.h>
|
|
#include <asm/hw_irq.h>
|
|
#include <asm/ppc-pci.h>
|
|
|
|
static int query_token, change_token;
|
|
|
|
#define RTAS_QUERY_FN 0
|
|
#define RTAS_CHANGE_FN 1
|
|
#define RTAS_RESET_FN 2
|
|
#define RTAS_CHANGE_MSI_FN 3
|
|
#define RTAS_CHANGE_MSIX_FN 4
|
|
#define RTAS_CHANGE_32MSI_FN 5
|
|
|
|
/* RTAS Helpers */
|
|
|
|
static int rtas_change_msi(struct pci_dn *pdn, u32 func, u32 num_irqs)
|
|
{
|
|
u32 addr, seq_num, rtas_ret[3];
|
|
unsigned long buid;
|
|
int rc;
|
|
|
|
addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
|
|
buid = pdn->phb->buid;
|
|
|
|
seq_num = 1;
|
|
do {
|
|
if (func == RTAS_CHANGE_MSI_FN || func == RTAS_CHANGE_MSIX_FN ||
|
|
func == RTAS_CHANGE_32MSI_FN)
|
|
rc = rtas_call(change_token, 6, 4, rtas_ret, addr,
|
|
BUID_HI(buid), BUID_LO(buid),
|
|
func, num_irqs, seq_num);
|
|
else
|
|
rc = rtas_call(change_token, 6, 3, rtas_ret, addr,
|
|
BUID_HI(buid), BUID_LO(buid),
|
|
func, num_irqs, seq_num);
|
|
|
|
seq_num = rtas_ret[1];
|
|
} while (rtas_busy_delay(rc));
|
|
|
|
/*
|
|
* If the RTAS call succeeded, return the number of irqs allocated.
|
|
* If not, make sure we return a negative error code.
|
|
*/
|
|
if (rc == 0)
|
|
rc = rtas_ret[0];
|
|
else if (rc > 0)
|
|
rc = -rc;
|
|
|
|
pr_debug("rtas_msi: ibm,change_msi(func=%d,num=%d), got %d rc = %d\n",
|
|
func, num_irqs, rtas_ret[0], rc);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static void rtas_disable_msi(struct pci_dev *pdev)
|
|
{
|
|
struct pci_dn *pdn;
|
|
|
|
pdn = pci_get_pdn(pdev);
|
|
if (!pdn)
|
|
return;
|
|
|
|
/*
|
|
* disabling MSI with the explicit interface also disables MSI-X
|
|
*/
|
|
if (rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, 0) != 0) {
|
|
/*
|
|
* may have failed because explicit interface is not
|
|
* present
|
|
*/
|
|
if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0) {
|
|
pr_debug("rtas_msi: Setting MSIs to 0 failed!\n");
|
|
}
|
|
}
|
|
}
|
|
|
|
static int rtas_query_irq_number(struct pci_dn *pdn, int offset)
|
|
{
|
|
u32 addr, rtas_ret[2];
|
|
unsigned long buid;
|
|
int rc;
|
|
|
|
addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
|
|
buid = pdn->phb->buid;
|
|
|
|
do {
|
|
rc = rtas_call(query_token, 4, 3, rtas_ret, addr,
|
|
BUID_HI(buid), BUID_LO(buid), offset);
|
|
} while (rtas_busy_delay(rc));
|
|
|
|
if (rc) {
|
|
pr_debug("rtas_msi: error (%d) querying source number\n", rc);
|
|
return rc;
|
|
}
|
|
|
|
return rtas_ret[0];
|
|
}
|
|
|
|
static void rtas_teardown_msi_irqs(struct pci_dev *pdev)
|
|
{
|
|
struct msi_desc *entry;
|
|
|
|
list_for_each_entry(entry, &pdev->msi_list, list) {
|
|
if (entry->irq == NO_IRQ)
|
|
continue;
|
|
|
|
irq_set_msi_desc(entry->irq, NULL);
|
|
irq_dispose_mapping(entry->irq);
|
|
}
|
|
|
|
rtas_disable_msi(pdev);
|
|
}
|
|
|
|
static int check_req(struct pci_dev *pdev, int nvec, char *prop_name)
|
|
{
|
|
struct device_node *dn;
|
|
struct pci_dn *pdn;
|
|
const u32 *req_msi;
|
|
|
|
pdn = pci_get_pdn(pdev);
|
|
if (!pdn)
|
|
return -ENODEV;
|
|
|
|
dn = pdn->node;
|
|
|
|
req_msi = of_get_property(dn, prop_name, NULL);
|
|
if (!req_msi) {
|
|
pr_debug("rtas_msi: No %s on %s\n", prop_name, dn->full_name);
|
|
return -ENOENT;
|
|
}
|
|
|
|
if (*req_msi < nvec) {
|
|
pr_debug("rtas_msi: %s requests < %d MSIs\n", prop_name, nvec);
|
|
|
|
if (*req_msi == 0) /* Be paranoid */
|
|
return -ENOSPC;
|
|
|
|
return *req_msi;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int check_req_msi(struct pci_dev *pdev, int nvec)
|
|
{
|
|
return check_req(pdev, nvec, "ibm,req#msi");
|
|
}
|
|
|
|
static int check_req_msix(struct pci_dev *pdev, int nvec)
|
|
{
|
|
return check_req(pdev, nvec, "ibm,req#msi-x");
|
|
}
|
|
|
|
/* Quota calculation */
|
|
|
|
static struct device_node *find_pe_total_msi(struct pci_dev *dev, int *total)
|
|
{
|
|
struct device_node *dn;
|
|
const u32 *p;
|
|
|
|
dn = of_node_get(pci_device_to_OF_node(dev));
|
|
while (dn) {
|
|
p = of_get_property(dn, "ibm,pe-total-#msi", NULL);
|
|
if (p) {
|
|
pr_debug("rtas_msi: found prop on dn %s\n",
|
|
dn->full_name);
|
|
*total = *p;
|
|
return dn;
|
|
}
|
|
|
|
dn = of_get_next_parent(dn);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static struct device_node *find_pe_dn(struct pci_dev *dev, int *total)
|
|
{
|
|
struct device_node *dn;
|
|
struct eeh_dev *edev;
|
|
|
|
/* Found our PE and assume 8 at that point. */
|
|
|
|
dn = pci_device_to_OF_node(dev);
|
|
if (!dn)
|
|
return NULL;
|
|
|
|
/* Get the top level device in the PE */
|
|
edev = of_node_to_eeh_dev(dn);
|
|
if (edev->pe)
|
|
edev = list_first_entry(&edev->pe->edevs, struct eeh_dev, list);
|
|
dn = eeh_dev_to_of_node(edev);
|
|
if (!dn)
|
|
return NULL;
|
|
|
|
/* We actually want the parent */
|
|
dn = of_get_parent(dn);
|
|
if (!dn)
|
|
return NULL;
|
|
|
|
/* Hardcode of 8 for old firmwares */
|
|
*total = 8;
|
|
pr_debug("rtas_msi: using PE dn %s\n", dn->full_name);
|
|
|
|
return dn;
|
|
}
|
|
|
|
struct msi_counts {
|
|
struct device_node *requestor;
|
|
int num_devices;
|
|
int request;
|
|
int quota;
|
|
int spare;
|
|
int over_quota;
|
|
};
|
|
|
|
static void *count_non_bridge_devices(struct device_node *dn, void *data)
|
|
{
|
|
struct msi_counts *counts = data;
|
|
const u32 *p;
|
|
u32 class;
|
|
|
|
pr_debug("rtas_msi: counting %s\n", dn->full_name);
|
|
|
|
p = of_get_property(dn, "class-code", NULL);
|
|
class = p ? *p : 0;
|
|
|
|
if ((class >> 8) != PCI_CLASS_BRIDGE_PCI)
|
|
counts->num_devices++;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void *count_spare_msis(struct device_node *dn, void *data)
|
|
{
|
|
struct msi_counts *counts = data;
|
|
const u32 *p;
|
|
int req;
|
|
|
|
if (dn == counts->requestor)
|
|
req = counts->request;
|
|
else {
|
|
/* We don't know if a driver will try to use MSI or MSI-X,
|
|
* so we just have to punt and use the larger of the two. */
|
|
req = 0;
|
|
p = of_get_property(dn, "ibm,req#msi", NULL);
|
|
if (p)
|
|
req = *p;
|
|
|
|
p = of_get_property(dn, "ibm,req#msi-x", NULL);
|
|
if (p)
|
|
req = max(req, (int)*p);
|
|
}
|
|
|
|
if (req < counts->quota)
|
|
counts->spare += counts->quota - req;
|
|
else if (req > counts->quota)
|
|
counts->over_quota++;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int msi_quota_for_device(struct pci_dev *dev, int request)
|
|
{
|
|
struct device_node *pe_dn;
|
|
struct msi_counts counts;
|
|
int total;
|
|
|
|
pr_debug("rtas_msi: calc quota for %s, request %d\n", pci_name(dev),
|
|
request);
|
|
|
|
pe_dn = find_pe_total_msi(dev, &total);
|
|
if (!pe_dn)
|
|
pe_dn = find_pe_dn(dev, &total);
|
|
|
|
if (!pe_dn) {
|
|
pr_err("rtas_msi: couldn't find PE for %s\n", pci_name(dev));
|
|
goto out;
|
|
}
|
|
|
|
pr_debug("rtas_msi: found PE %s\n", pe_dn->full_name);
|
|
|
|
memset(&counts, 0, sizeof(struct msi_counts));
|
|
|
|
/* Work out how many devices we have below this PE */
|
|
traverse_pci_devices(pe_dn, count_non_bridge_devices, &counts);
|
|
|
|
if (counts.num_devices == 0) {
|
|
pr_err("rtas_msi: found 0 devices under PE for %s\n",
|
|
pci_name(dev));
|
|
goto out;
|
|
}
|
|
|
|
counts.quota = total / counts.num_devices;
|
|
if (request <= counts.quota)
|
|
goto out;
|
|
|
|
/* else, we have some more calculating to do */
|
|
counts.requestor = pci_device_to_OF_node(dev);
|
|
counts.request = request;
|
|
traverse_pci_devices(pe_dn, count_spare_msis, &counts);
|
|
|
|
/* If the quota isn't an integer multiple of the total, we can
|
|
* use the remainder as spare MSIs for anyone that wants them. */
|
|
counts.spare += total % counts.num_devices;
|
|
|
|
/* Divide any spare by the number of over-quota requestors */
|
|
if (counts.over_quota)
|
|
counts.quota += counts.spare / counts.over_quota;
|
|
|
|
/* And finally clamp the request to the possibly adjusted quota */
|
|
request = min(counts.quota, request);
|
|
|
|
pr_debug("rtas_msi: request clamped to quota %d\n", request);
|
|
out:
|
|
of_node_put(pe_dn);
|
|
|
|
return request;
|
|
}
|
|
|
|
static int rtas_msi_check_device(struct pci_dev *pdev, int nvec, int type)
|
|
{
|
|
int quota, rc;
|
|
|
|
if (type == PCI_CAP_ID_MSIX)
|
|
rc = check_req_msix(pdev, nvec);
|
|
else
|
|
rc = check_req_msi(pdev, nvec);
|
|
|
|
if (rc)
|
|
return rc;
|
|
|
|
quota = msi_quota_for_device(pdev, nvec);
|
|
|
|
if (quota && quota < nvec)
|
|
return quota;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int check_msix_entries(struct pci_dev *pdev)
|
|
{
|
|
struct msi_desc *entry;
|
|
int expected;
|
|
|
|
/* There's no way for us to express to firmware that we want
|
|
* a discontiguous, or non-zero based, range of MSI-X entries.
|
|
* So we must reject such requests. */
|
|
|
|
expected = 0;
|
|
list_for_each_entry(entry, &pdev->msi_list, list) {
|
|
if (entry->msi_attrib.entry_nr != expected) {
|
|
pr_debug("rtas_msi: bad MSI-X entries.\n");
|
|
return -EINVAL;
|
|
}
|
|
expected++;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rtas_setup_msi_irqs(struct pci_dev *pdev, int nvec_in, int type)
|
|
{
|
|
struct pci_dn *pdn;
|
|
int hwirq, virq, i, rc;
|
|
struct msi_desc *entry;
|
|
struct msi_msg msg;
|
|
int nvec = nvec_in;
|
|
|
|
pdn = pci_get_pdn(pdev);
|
|
if (!pdn)
|
|
return -ENODEV;
|
|
|
|
if (type == PCI_CAP_ID_MSIX && check_msix_entries(pdev))
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Firmware currently refuse any non power of two allocation
|
|
* so we round up if the quota will allow it.
|
|
*/
|
|
if (type == PCI_CAP_ID_MSIX) {
|
|
int m = roundup_pow_of_two(nvec);
|
|
int quota = msi_quota_for_device(pdev, m);
|
|
|
|
if (quota >= m)
|
|
nvec = m;
|
|
}
|
|
|
|
/*
|
|
* Try the new more explicit firmware interface, if that fails fall
|
|
* back to the old interface. The old interface is known to never
|
|
* return MSI-Xs.
|
|
*/
|
|
again:
|
|
if (type == PCI_CAP_ID_MSI) {
|
|
if (pdn->force_32bit_msi)
|
|
rc = rtas_change_msi(pdn, RTAS_CHANGE_32MSI_FN, nvec);
|
|
else
|
|
rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
|
|
|
|
if (rc < 0 && !pdn->force_32bit_msi) {
|
|
pr_debug("rtas_msi: trying the old firmware call.\n");
|
|
rc = rtas_change_msi(pdn, RTAS_CHANGE_FN, nvec);
|
|
}
|
|
} else
|
|
rc = rtas_change_msi(pdn, RTAS_CHANGE_MSIX_FN, nvec);
|
|
|
|
if (rc != nvec) {
|
|
if (nvec != nvec_in) {
|
|
nvec = nvec_in;
|
|
goto again;
|
|
}
|
|
pr_debug("rtas_msi: rtas_change_msi() failed\n");
|
|
return rc;
|
|
}
|
|
|
|
i = 0;
|
|
list_for_each_entry(entry, &pdev->msi_list, list) {
|
|
hwirq = rtas_query_irq_number(pdn, i++);
|
|
if (hwirq < 0) {
|
|
pr_debug("rtas_msi: error (%d) getting hwirq\n", rc);
|
|
return hwirq;
|
|
}
|
|
|
|
virq = irq_create_mapping(NULL, hwirq);
|
|
|
|
if (virq == NO_IRQ) {
|
|
pr_debug("rtas_msi: Failed mapping hwirq %d\n", hwirq);
|
|
return -ENOSPC;
|
|
}
|
|
|
|
dev_dbg(&pdev->dev, "rtas_msi: allocated virq %d\n", virq);
|
|
irq_set_msi_desc(virq, entry);
|
|
|
|
/* Read config space back so we can restore after reset */
|
|
read_msi_msg(virq, &msg);
|
|
entry->msg = msg;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void rtas_msi_pci_irq_fixup(struct pci_dev *pdev)
|
|
{
|
|
/* No LSI -> leave MSIs (if any) configured */
|
|
if (pdev->irq == NO_IRQ) {
|
|
dev_dbg(&pdev->dev, "rtas_msi: no LSI, nothing to do.\n");
|
|
return;
|
|
}
|
|
|
|
/* No MSI -> MSIs can't have been assigned by fw, leave LSI */
|
|
if (check_req_msi(pdev, 1) && check_req_msix(pdev, 1)) {
|
|
dev_dbg(&pdev->dev, "rtas_msi: no req#msi/x, nothing to do.\n");
|
|
return;
|
|
}
|
|
|
|
dev_dbg(&pdev->dev, "rtas_msi: disabling existing MSI.\n");
|
|
rtas_disable_msi(pdev);
|
|
}
|
|
|
|
static int rtas_msi_init(void)
|
|
{
|
|
query_token = rtas_token("ibm,query-interrupt-source-number");
|
|
change_token = rtas_token("ibm,change-msi");
|
|
|
|
if ((query_token == RTAS_UNKNOWN_SERVICE) ||
|
|
(change_token == RTAS_UNKNOWN_SERVICE)) {
|
|
pr_debug("rtas_msi: no RTAS tokens, no MSI support.\n");
|
|
return -1;
|
|
}
|
|
|
|
pr_debug("rtas_msi: Registering RTAS MSI callbacks.\n");
|
|
|
|
WARN_ON(ppc_md.setup_msi_irqs);
|
|
ppc_md.setup_msi_irqs = rtas_setup_msi_irqs;
|
|
ppc_md.teardown_msi_irqs = rtas_teardown_msi_irqs;
|
|
ppc_md.msi_check_device = rtas_msi_check_device;
|
|
|
|
WARN_ON(ppc_md.pci_irq_fixup);
|
|
ppc_md.pci_irq_fixup = rtas_msi_pci_irq_fixup;
|
|
|
|
return 0;
|
|
}
|
|
arch_initcall(rtas_msi_init);
|
|
|