diff options
| -rw-r--r-- | arch/powerpc/platforms/pseries/Makefile | 1 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pseries/msi.c | 270 |
2 files changed, 271 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile index 90235d5..ae1fc92 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 0000000..6063ea2 --- /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); |