arch/powerpc/platforms/4xx/msi.c

   1 /*
   2  * Adding PCI-E MSI support for PPC4XX SoCs.
   3  *
   4  * Copyright (c) 2010, Applied Micro Circuits Corporation
   5  * Authors:     Tirumala R Marri <tmarri@apm.com>
   6  *              Feng Kan <fkan@apm.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <linux/irq.h>
  25 #include <linux/pci.h>
  26 #include <linux/msi.h>
  27 #include <linux/of_platform.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/export.h>
  30 #include <linux/kernel.h>
  31 #include <asm/prom.h>
  32 #include <asm/hw_irq.h>
  33 #include <asm/ppc-pci.h>
  34 #include <asm/dcr.h>
  35 #include <asm/dcr-regs.h>
  36 #include <asm/msi_bitmap.h>
  37
  38 #define PEIH_TERMADH    0x00
  39 #define PEIH_TERMADL    0x08
  40 #define PEIH_MSIED      0x10
  41 #define PEIH_MSIMK      0x18
  42 #define PEIH_MSIASS     0x20
  43 #define PEIH_FLUSH0     0x30
  44 #define PEIH_FLUSH1     0x38
  45 #define PEIH_CNTRST     0x48
  46
  47 static int msi_irqs;
  48
  49 struct ppc4xx_msi {
  50         u32 msi_addr_lo;
  51         u32 msi_addr_hi;
  52         void __iomem *msi_regs;
  53         int *msi_virqs;
  54         struct msi_bitmap bitmap;
  55         struct device_node *msi_dev;
  56 };
  57
  58 static struct ppc4xx_msi ppc4xx_msi;
  59
  60 static int ppc4xx_msi_init_allocator(struct platform_device *dev,
  61                 struct ppc4xx_msi *msi_data)
  62 {
  63         int err;
  64
  65         err = msi_bitmap_alloc(&msi_data->bitmap, msi_irqs,
  66                               dev->dev.of_node);
  67         if (err)
  68                 return err;
  69
  70         err = msi_bitmap_reserve_dt_hwirqs(&msi_data->bitmap);
  71         if (err < 0) {
  72                 msi_bitmap_free(&msi_data->bitmap);
  73                 return err;
  74         }
  75
  76         return 0;
  77 }
  78
  79 static int ppc4xx_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  80 {
  81         int int_no = -ENOMEM;
  82         unsigned int virq;
  83         struct msi_msg msg;
  84         struct msi_desc *entry;
  85         struct ppc4xx_msi *msi_data = &ppc4xx_msi;
  86
  87         dev_dbg(&dev->dev, "PCIE-MSI:%s called. vec %x type %d\n",
  88                 __func__, nvec, type);
  89         if (type == PCI_CAP_ID_MSIX)
  90                 pr_debug("ppc4xx msi: MSI-X untested, trying anyway.\n");
  91
  92         msi_data->msi_virqs = kmalloc_array(msi_irqs, sizeof(int), GFP_KERNEL);
  93         if (!msi_data->msi_virqs)
  94                 return -ENOMEM;
  95
  96         for_each_pci_msi_entry(entry, dev) {
  97                 int_no = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
  98                 if (int_no >= 0)
  99                         break;
 100                 if (int_no < 0) {
 101                         pr_debug("%s: fail allocating msi interrupt\n",
 102                                         __func__);
 103                 }
 104                 virq = irq_of_parse_and_map(msi_data->msi_dev, int_no);
 105                 if (!virq) {
 106                         dev_err(&dev->dev, "%s: fail mapping irq\n", __func__);
 107                         msi_bitmap_free_hwirqs(&msi_data->bitmap, int_no, 1);
 108                         return -ENOSPC;
 109                 }
 110                 dev_dbg(&dev->dev, "%s: virq = %d\n", __func__, virq);
 111
 112                 /* Setup msi address space */
 113                 msg.address_hi = msi_data->msi_addr_hi;
 114                 msg.address_lo = msi_data->msi_addr_lo;
 115
 116                 irq_set_msi_desc(virq, entry);
 117                 msg.data = int_no;
 118                 pci_write_msi_msg(virq, &msg);
 119         }
 120         return 0;
 121 }
 122
 123 void ppc4xx_teardown_msi_irqs(struct pci_dev *dev)
 124 {
 125         struct msi_desc *entry;
 126         struct ppc4xx_msi *msi_data = &ppc4xx_msi;
 127         irq_hw_number_t hwirq;
 128
 129         dev_dbg(&dev->dev, "PCIE-MSI: tearing down msi irqs\n");
 130
 131         for_each_pci_msi_entry(entry, dev) {
 132                 if (!entry->irq)
 133                         continue;
 134                 hwirq = virq_to_hw(entry->irq);
 135                 irq_set_msi_desc(entry->irq, NULL);
 136                 irq_dispose_mapping(entry->irq);
 137                 msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
 138         }
 139 }
 140
 141 static int ppc4xx_setup_pcieh_hw(struct platform_device *dev,
 142                                  struct resource res, struct ppc4xx_msi *msi)
 143 {
 144         const u32 *msi_data;
 145         const u32 *msi_mask;
 146         const u32 *sdr_addr;
 147         dma_addr_t msi_phys;
 148         void *msi_virt;
 149         int err;
 150
 151         sdr_addr = of_get_property(dev->dev.of_node, "sdr-base", NULL);
 152         if (!sdr_addr)
 153                 return -EINVAL;
 154
 155         msi_data = of_get_property(dev->dev.of_node, "msi-data", NULL);
 156         if (!msi_data)
 157                 return -EINVAL;
 158
 159         msi_mask = of_get_property(dev->dev.of_node, "msi-mask", NULL);
 160         if (!msi_mask)
 161                 return -EINVAL;
 162
 163         msi->msi_dev = of_find_node_by_name(NULL, "ppc4xx-msi");
 164         if (!msi->msi_dev)
 165                 return -ENODEV;
 166
 167         msi->msi_regs = of_iomap(msi->msi_dev, 0);
 168         if (!msi->msi_regs) {
 169                 dev_err(&dev->dev, "of_iomap failed\n");
 170                 err = -ENOMEM;
 171                 goto node_put;
 172         }
 173         dev_dbg(&dev->dev, "PCIE-MSI: msi register mapped 0x%x 0x%x\n",
 174                 (u32) (msi->msi_regs + PEIH_TERMADH), (u32) (msi->msi_regs));
 175
 176         msi_virt = dma_alloc_coherent(&dev->dev, 64, &msi_phys, GFP_KERNEL);
 177         if (!msi_virt) {
 178                 err = -ENOMEM;
 179                 goto iounmap;
 180         }
 181         msi->msi_addr_hi = upper_32_bits(msi_phys);
 182         msi->msi_addr_lo = lower_32_bits(msi_phys & 0xffffffff);
 183         dev_dbg(&dev->dev, "PCIE-MSI: msi address high 0x%x, low 0x%x\n",
 184                 msi->msi_addr_hi, msi->msi_addr_lo);
 185
 186         mtdcri(SDR0, *sdr_addr, upper_32_bits(res.start));      /*HIGH addr */
 187         mtdcri(SDR0, *sdr_addr + 1, lower_32_bits(res.start));  /* Low addr */
 188
 189         /* Progam the Interrupt handler Termination addr registers */
 190         out_be32(msi->msi_regs + PEIH_TERMADH, msi->msi_addr_hi);
 191         out_be32(msi->msi_regs + PEIH_TERMADL, msi->msi_addr_lo);
 192
 193         /* Program MSI Expected data and Mask bits */
 194         out_be32(msi->msi_regs + PEIH_MSIED, *msi_data);
 195         out_be32(msi->msi_regs + PEIH_MSIMK, *msi_mask);
 196
 197         dma_free_coherent(&dev->dev, 64, msi_virt, msi_phys);
 198
 199         return 0;
 200
 201 iounmap:
 202         iounmap(msi->msi_regs);
 203 node_put:
 204         of_node_put(msi->msi_dev);
 205         return err;
 206 }
 207
 208 static int ppc4xx_of_msi_remove(struct platform_device *dev)
 209 {
 210         struct ppc4xx_msi *msi = dev->dev.platform_data;
 211         int i;
 212         int virq;
 213
 214         for (i = 0; i < msi_irqs; i++) {
 215                 virq = msi->msi_virqs[i];
 216                 if (virq)
 217                         irq_dispose_mapping(virq);
 218         }
 219
 220         if (msi->bitmap.bitmap)
 221                 msi_bitmap_free(&msi->bitmap);
 222         iounmap(msi->msi_regs);
 223         of_node_put(msi->msi_dev);
 224
 225         return 0;
 226 }
 227
 228 static int ppc4xx_msi_probe(struct platform_device *dev)
 229 {
 230         struct ppc4xx_msi *msi;
 231         struct resource res;
 232         int err = 0;
 233         struct pci_controller *phb;
 234
 235         dev_dbg(&dev->dev, "PCIE-MSI: Setting up MSI support...\n");
 236
 237         msi = devm_kzalloc(&dev->dev, sizeof(*msi), GFP_KERNEL);
 238         if (!msi)
 239                 return -ENOMEM;
 240         dev->dev.platform_data = msi;
 241
 242         /* Get MSI ranges */
 243         err = of_address_to_resource(dev->dev.of_node, 0, &res);
 244         if (err) {
 245                 dev_err(&dev->dev, "%pOF resource error!\n", dev->dev.of_node);
 246                 return err;
 247         }
 248
 249         msi_irqs = of_irq_count(dev->dev.of_node);
 250         if (!msi_irqs)
 251                 return -ENODEV;
 252
 253         err = ppc4xx_setup_pcieh_hw(dev, res, msi);
 254         if (err)
 255                 return err;
 256
 257         err = ppc4xx_msi_init_allocator(dev, msi);
 258         if (err) {
 259                 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
 260                 goto error_out;
 261         }
 262         ppc4xx_msi = *msi;
 263
 264         list_for_each_entry(phb, &hose_list, list_node) {
 265                 phb->controller_ops.setup_msi_irqs = ppc4xx_setup_msi_irqs;
 266                 phb->controller_ops.teardown_msi_irqs = ppc4xx_teardown_msi_irqs;
 267         }
 268         return 0;
 269
 270 error_out:
 271         ppc4xx_of_msi_remove(dev);
 272         return err;
 273 }
 274 static const struct of_device_id ppc4xx_msi_ids[] = {
 275         {
 276                 .compatible = "amcc,ppc4xx-msi",
 277         },
 278         {}
 279 };
 280 static struct platform_driver ppc4xx_msi_driver = {
 281         .probe = ppc4xx_msi_probe,
 282         .remove = ppc4xx_of_msi_remove,
 283         .driver = {
 284                    .name = "ppc4xx-msi",
 285                    .of_match_table = ppc4xx_msi_ids,
 286                    },
 287
 288 };
 289
 290 static __init int ppc4xx_msi_init(void)
 291 {
 292         return platform_driver_register(&ppc4xx_msi_driver);
 293 }
 294
 295 subsys_initcall(ppc4xx_msi_init);