arch/powerpc/platforms/wsp/msi.c

   1 /*
   2  * Copyright 2011 Michael Ellerman, IBM Corp.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/pci.h>
  12 #include <linux/msi.h>
  13 #include <linux/irq.h>
  14 #include <linux/interrupt.h>
  15
  16 #include "msi.h"
  17 #include "ics.h"
  18 #include "wsp_pci.h"
  19
  20 /* Magic addresses for 32 & 64-bit MSIs with hardcoded MVE 0 */
  21 #define MSI_ADDR_32             0xFFFF0000ul
  22 #define MSI_ADDR_64             0x1000000000000000ul
  23
  24 int wsp_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  25 {
  26         struct pci_controller *phb;
  27         struct msi_desc *entry;
  28         struct msi_msg msg;
  29         unsigned int virq;
  30         int hwirq;
  31
  32         phb = pci_bus_to_host(dev->bus);
  33         if (!phb)
  34                 return -ENOENT;
  35
  36         entry = list_first_entry(&dev->msi_list, struct msi_desc, list);
  37         if (entry->msi_attrib.is_64) {
  38                 msg.address_lo = 0;
  39                 msg.address_hi = MSI_ADDR_64 >> 32;
  40         } else {
  41                 msg.address_lo = MSI_ADDR_32;
  42                 msg.address_hi = 0;
  43         }
  44
  45         list_for_each_entry(entry, &dev->msi_list, list) {
  46                 hwirq = wsp_ics_alloc_irq(phb->dn, 1);
  47                 if (hwirq < 0) {
  48                         dev_warn(&dev->dev, "wsp_msi: hwirq alloc failed!\n");
  49                         return hwirq;
  50                 }
  51
  52                 virq = irq_create_mapping(NULL, hwirq);
  53                 if (virq == NO_IRQ) {
  54                         dev_warn(&dev->dev, "wsp_msi: virq alloc failed!\n");
  55                         return -1;
  56                 }
  57
  58                 dev_dbg(&dev->dev, "wsp_msi: allocated irq %#x/%#x\n",
  59                         hwirq, virq);
  60
  61                 wsp_ics_set_msi_chip(virq);
  62                 irq_set_msi_desc(virq, entry);
  63                 msg.data = hwirq & XIVE_ADDR_MASK;
  64                 write_msi_msg(virq, &msg);
  65         }
  66
  67         return 0;
  68 }
  69
  70 void wsp_teardown_msi_irqs(struct pci_dev *dev)
  71 {
  72         struct pci_controller *phb;
  73         struct msi_desc *entry;
  74         int hwirq;
  75
  76         phb = pci_bus_to_host(dev->bus);
  77
  78         dev_dbg(&dev->dev, "wsp_msi: tearing down msi irqs\n");
  79
  80         list_for_each_entry(entry, &dev->msi_list, list) {
  81                 if (entry->irq == NO_IRQ)
  82                         continue;
  83
  84                 irq_set_msi_desc(entry->irq, NULL);
  85                 wsp_ics_set_std_chip(entry->irq);
  86
  87                 hwirq = virq_to_hw(entry->irq);
  88                 /* In this order to avoid racing with irq_create_mapping() */
  89                 irq_dispose_mapping(entry->irq);
  90                 wsp_ics_free_irq(phb->dn, hwirq);
  91         }
  92 }
  93
  94 void wsp_setup_phb_msi(struct pci_controller *phb)
  95 {
  96         /* Create a single MVE at offset 0 that matches everything */
  97         out_be64(phb->cfg_data + PCIE_REG_IODA_ADDR, PCIE_REG_IODA_AD_TBL_MVT);
  98         out_be64(phb->cfg_data + PCIE_REG_IODA_DATA0, 1ull << 63);
  99
 100         ppc_md.setup_msi_irqs = wsp_setup_msi_irqs;
 101         ppc_md.teardown_msi_irqs = wsp_teardown_msi_irqs;
 102 }