seq_num = rtas_ret[1];
} while (rtas_busy_delay(rc));
- if (rc == 0) /* Success */
+ /*
+ * 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) = (%d)\n",
- func, num_irqs, 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;
}
rtas_disable_msi(pdev);
}
-static int check_req_msi(struct pci_dev *pdev, int nvec)
+static int check_req(struct pci_dev *pdev, int nvec, char *prop_name)
{
struct device_node *dn;
struct pci_dn *pdn;
dn = pdn->node;
- req_msi = of_get_property(dn, "ibm,req#msi", NULL);
+ req_msi = of_get_property(dn, prop_name, NULL);
if (!req_msi) {
- pr_debug("rtas_msi: No ibm,req#msi on %s\n", dn->full_name);
+ pr_debug("rtas_msi: No %s on %s\n", prop_name, dn->full_name);
return -ENOENT;
}
if (*req_msi < nvec) {
- pr_debug("rtas_msi: ibm,req#msi requests < %d MSIs\n", nvec);
- return -ENOSPC;
+ 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;
+
+ /* Found our PE and assume 8 at that point. */
+
+ dn = pci_device_to_OF_node(dev);
+ if (!dn)
+ return NULL;
+
+ dn = find_device_pe(dn);
+ 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)
- pr_debug("rtas_msi: MSI-X untested, trying anyway.\n");
+ rc = check_req_msix(pdev, nvec);
+ else
+ rc = check_req_msi(pdev, nvec);
- return 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, int type)
struct pci_dn *pdn;
int hwirq, virq, i, rc;
struct msi_desc *entry;
+ struct msi_msg msg;
pdn = get_pdn(pdev);
if (!pdn)
return -ENODEV;
+ if (type == PCI_CAP_ID_MSIX && check_msix_entries(pdev))
+ return -EINVAL;
+
/*
* Try the new more explicit firmware interface, if that fails fall
* back to the old interface. The old interface is known to never
if (type == PCI_CAP_ID_MSI) {
rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
- if (rc != nvec) {
+ if (rc < 0) {
pr_debug("rtas_msi: trying the old firmware call.\n");
rc = rtas_change_msi(pdn, RTAS_CHANGE_FN, nvec);
}
if (rc != nvec) {
pr_debug("rtas_msi: rtas_change_msi() failed\n");
-
- /*
- * In case of an error it's not clear whether the device is
- * left with MSI enabled or not, so we explicitly disable.
- */
- goto out_free;
+ return rc;
}
i = 0;
list_for_each_entry(entry, &pdev->msi_list, list) {
- hwirq = rtas_query_irq_number(pdn, i);
+ hwirq = rtas_query_irq_number(pdn, i++);
if (hwirq < 0) {
- rc = hwirq;
pr_debug("rtas_msi: error (%d) getting hwirq\n", rc);
- goto out_free;
+ return hwirq;
}
virq = irq_create_mapping(NULL, hwirq);
if (virq == NO_IRQ) {
pr_debug("rtas_msi: Failed mapping hwirq %d\n", hwirq);
- rc = -ENOSPC;
- goto out_free;
+ return -ENOSPC;
}
dev_dbg(&pdev->dev, "rtas_msi: allocated virq %d\n", virq);
set_irq_msi(virq, entry);
+
+ /* Read config space back so we can restore after reset */
+ read_msi_msg(virq, &msg);
+ entry->msg = msg;
+
unmask_msi_irq(virq);
}
return 0;
-
- out_free:
- rtas_teardown_msi_irqs(pdev);
- return rc;
}
static void rtas_msi_pci_irq_fixup(struct pci_dev *pdev)
}
/* No MSI -> MSIs can't have been assigned by fw, leave LSI */
- if (check_req_msi(pdev, 1)) {
- dev_dbg(&pdev->dev, "rtas_msi: no req#msi, nothing to do.\n");
+ 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;
}
git.openpandora.org / pandora-kernel.git / blobdiff