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-rw-r--r--arch/powerpc/platforms/pseries/Makefile1
-rw-r--r--arch/powerpc/platforms/pseries/msi.c270
2 files changed, 271 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index 90235d598751..ae1fc92dc1c9 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_SCANLOG) += scanlog.o
obj-$(CONFIG_EEH) += eeh.o eeh_cache.o eeh_driver.o eeh_event.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_PCI) += pci.o pci_dlpar.o
+obj-$(CONFIG_PCI_MSI) += msi.o
obj-$(CONFIG_HOTPLUG_CPU) += hotplug-cpu.o
diff --git a/arch/powerpc/platforms/pseries/msi.c b/arch/powerpc/platforms/pseries/msi.c
new file mode 100644
index 000000000000..6063ea2f67ad
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/msi.c
@@ -0,0 +1,270 @@
+/*
+ * 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
+
+static struct pci_dn *get_pdn(struct pci_dev *pdev)
+{
+ struct device_node *dn;
+ struct pci_dn *pdn;
+
+ dn = pci_device_to_OF_node(pdev);
+ if (!dn) {
+ dev_dbg(&pdev->dev, "rtas_msi: No OF device node\n");
+ return NULL;
+ }
+
+ pdn = PCI_DN(dn);
+ if (!pdn) {
+ dev_dbg(&pdev->dev, "rtas_msi: No PCI DN\n");
+ return NULL;
+ }
+
+ return pdn;
+}
+
+/* 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)
+ 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 (rc == 0) /* Success */
+ rc = rtas_ret[0];
+
+ pr_debug("rtas_msi: ibm,change_msi(func=%d,num=%d) = (%d)\n",
+ func, num_irqs, rc);
+
+ return rc;
+}
+
+static void rtas_disable_msi(struct pci_dev *pdev)
+{
+ struct pci_dn *pdn;
+
+ pdn = get_pdn(pdev);
+ if (!pdn)
+ return;
+
+ 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;
+
+ set_irq_msi(entry->irq, NULL);
+ irq_dispose_mapping(entry->irq);
+ }
+
+ rtas_disable_msi(pdev);
+}
+
+static int check_req_msi(struct pci_dev *pdev, int nvec)
+{
+ struct device_node *dn;
+ struct pci_dn *pdn;
+ const u32 *req_msi;
+
+ pdn = get_pdn(pdev);
+ if (!pdn)
+ return -ENODEV;
+
+ dn = pdn->node;
+
+ req_msi = of_get_property(dn, "ibm,req#msi", NULL);
+ if (!req_msi) {
+ pr_debug("rtas_msi: No ibm,req#msi on %s\n", dn->full_name);
+ return -ENOENT;
+ }
+
+ if (*req_msi < nvec) {
+ pr_debug("rtas_msi: ibm,req#msi requests < %d MSIs\n", nvec);
+ return -ENOSPC;
+ }
+
+ return 0;
+}
+
+static int rtas_msi_check_device(struct pci_dev *pdev, int nvec, int type)
+{
+ if (type == PCI_CAP_ID_MSIX)
+ pr_debug("rtas_msi: MSI-X untested, trying anyway.\n");
+
+ return check_req_msi(pdev, nvec);
+}
+
+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;
+
+ pdn = get_pdn(pdev);
+ if (!pdn)
+ return -ENODEV;
+
+ /*
+ * 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.
+ */
+ if (type == PCI_CAP_ID_MSI) {
+ rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
+
+ if (rc != nvec) {
+ 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) {
+ 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;
+ }
+
+ i = 0;
+ list_for_each_entry(entry, &pdev->msi_list, list) {
+ 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;
+ }
+
+ 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;
+ }
+
+ dev_dbg(&pdev->dev, "rtas_msi: allocated virq %d\n", virq);
+ set_irq_msi(virq, entry);
+ 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 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)) {
+ dev_dbg(&pdev->dev, "rtas_msi: no req#msi, 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);