arch/powerpc/sysdev/ppc4xx_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/bootmem.h>
  26 #include <linux/pci.h>
  27 #include <linux/msi.h>
  28 #include <linux/of_platform.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/export.h>
  31 #include <linux/kernel.h>
  32 #include <asm/prom.h>
  33 #include <asm/hw_irq.h>
  34 #include <asm/ppc-pci.h>
  35 #include <asm/dcr.h>
  36 #include <asm/dcr-regs.h>
  37 #include <asm/msi_bitmap.h>
  38
  39 #define PEIH_TERMADH    0x00
  40 #define PEIH_TERMADL    0x08
  41 #define PEIH_MSIED      0x10
  42 #define PEIH_MSIMK      0x18
  43 #define PEIH_MSIASS     0x20
  44 #define PEIH_FLUSH0     0x30
  45 #define PEIH_FLUSH1     0x38
  46 #define PEIH_CNTRST     0x48
  47
  48 static int msi_irqs;
  49
  50 struct ppc4xx_msi {
  51         u32 msi_addr_lo;
  52         u32 msi_addr_hi;
  53         void __iomem *msi_regs;
  54         int *msi_virqs;
  55         struct msi_bitmap bitmap;
  56         struct device_node *msi_dev;
  57 };
  58
  59 static struct ppc4xx_msi ppc4xx_msi;
  60
  61 static int ppc4xx_msi_init_allocator(struct platform_device *dev,
  62                 struct ppc4xx_msi *msi_data)
  63 {
  64         int err;
  65
  66         err = msi_bitmap_alloc(&msi_data->bitmap, msi_irqs,
  67                               dev->dev.of_node);
  68         if (err)
  69                 return err;
  70
  71         err = msi_bitmap_reserve_dt_hwirqs(&msi_data->bitmap);
  72         if (err < 0) {
  73                 msi_bitmap_free(&msi_data->bitmap);
  74                 return err;
  75         }
  76
  77         return 0;
  78 }
  79
  80 static int ppc4xx_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  81 {
  82         int int_no = -ENOMEM;
  83         unsigned int virq;
  84         struct msi_msg msg;
  85         struct msi_desc *entry;
  86         struct ppc4xx_msi *msi_data = &ppc4xx_msi;
  87
  88         msi_data->msi_virqs = kmalloc((msi_irqs) * sizeof(int),
  89                                             GFP_KERNEL);
  90         if (!msi_data->msi_virqs)
  91                 return -ENOMEM;
  92
  93         list_for_each_entry(entry, &dev->msi_list, list) {
  94                 int_no = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
  95                 if (int_no >= 0)
  96                         break;
  97                 if (int_no < 0) {
  98                         pr_debug("%s: fail allocating msi interrupt\n",
  99                                         __func__);
 100                 }
 101                 virq = irq_of_parse_and_map(msi_data->msi_dev, int_no);
 102                 if (virq == NO_IRQ) {
 103                         dev_err(&dev->dev, "%s: fail mapping irq\n", __func__);
 104                         msi_bitmap_free_hwirqs(&msi_data->bitmap, int_no, 1);
 105                         return -ENOSPC;
 106                 }
 107                 dev_dbg(&dev->dev, "%s: virq = %d\n", __func__, virq);
 108
 109                 /* Setup msi address space */
 110                 msg.address_hi = msi_data->msi_addr_hi;
 111                 msg.address_lo = msi_data->msi_addr_lo;
 112
 113                 irq_set_msi_desc(virq, entry);
 114                 msg.data = int_no;
 115                 write_msi_msg(virq, &msg);
 116         }
 117         return 0;
 118 }
 119
 120 void ppc4xx_teardown_msi_irqs(struct pci_dev *dev)
 121 {
 122         struct msi_desc *entry;
 123         struct ppc4xx_msi *msi_data = &ppc4xx_msi;
 124
 125         dev_dbg(&dev->dev, "PCIE-MSI: tearing down msi irqs\n");
 126
 127         list_for_each_entry(entry, &dev->msi_list, list) {
 128                 if (entry->irq == NO_IRQ)
 129                         continue;
 130                 irq_set_msi_desc(entry->irq, NULL);
 131                 msi_bitmap_free_hwirqs(&msi_data->bitmap,
 132                                 virq_to_hw(entry->irq), 1);
 133                 irq_dispose_mapping(entry->irq);
 134         }
 135 }
 136
 137 static int ppc4xx_msi_check_device(struct pci_dev *pdev, int nvec, int type)
 138 {
 139         dev_dbg(&pdev->dev, "PCIE-MSI:%s called. vec %x type %d\n",
 140                 __func__, nvec, type);
 141         if (type == PCI_CAP_ID_MSIX)
 142                 pr_debug("ppc4xx msi: MSI-X untested, trying anyway.\n");
 143
 144         return 0;
 145 }
 146
 147 static int ppc4xx_setup_pcieh_hw(struct platform_device *dev,
 148                                  struct resource res, struct ppc4xx_msi *msi)
 149 {
 150         const u32 *msi_data;
 151         const u32 *msi_mask;
 152         const u32 *sdr_addr;
 153         dma_addr_t msi_phys;
 154         void *msi_virt;
 155
 156         sdr_addr = of_get_property(dev->dev.of_node, "sdr-base", NULL);
 157         if (!sdr_addr)
 158                 return -1;
 159
 160         mtdcri(SDR0, *sdr_addr, upper_32_bits(res.start));      /*HIGH addr */
 161         mtdcri(SDR0, *sdr_addr + 1, lower_32_bits(res.start));  /* Low addr */
 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 problem failed\n");
 170                 return -ENOMEM;
 171         }
 172         dev_dbg(&dev->dev, "PCIE-MSI: msi register mapped 0x%x 0x%x\n",
 173                 (u32) (msi->msi_regs + PEIH_TERMADH), (u32) (msi->msi_regs));
 174
 175         msi_virt = dma_alloc_coherent(&dev->dev, 64, &msi_phys, GFP_KERNEL);
 176         if (!msi_virt)
 177                 return -ENOMEM;
 178         msi->msi_addr_hi = upper_32_bits(msi_phys);
 179         msi->msi_addr_lo = lower_32_bits(msi_phys & 0xffffffff);
 180         dev_dbg(&dev->dev, "PCIE-MSI: msi address high 0x%x, low 0x%x\n",
 181                 msi->msi_addr_hi, msi->msi_addr_lo);
 182
 183         /* Progam the Interrupt handler Termination addr registers */
 184         out_be32(msi->msi_regs + PEIH_TERMADH, msi->msi_addr_hi);
 185         out_be32(msi->msi_regs + PEIH_TERMADL, msi->msi_addr_lo);
 186
 187         msi_data = of_get_property(dev->dev.of_node, "msi-data", NULL);
 188         if (!msi_data)
 189                 return -1;
 190         msi_mask = of_get_property(dev->dev.of_node, "msi-mask", NULL);
 191         if (!msi_mask)
 192                 return -1;
 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
 202 static int ppc4xx_of_msi_remove(struct platform_device *dev)
 203 {
 204         struct ppc4xx_msi *msi = dev->dev.platform_data;
 205         int i;
 206         int virq;
 207
 208         for (i = 0; i < msi_irqs; i++) {
 209                 virq = msi->msi_virqs[i];
 210                 if (virq != NO_IRQ)
 211                         irq_dispose_mapping(virq);
 212         }
 213
 214         if (msi->bitmap.bitmap)
 215                 msi_bitmap_free(&msi->bitmap);
 216         iounmap(msi->msi_regs);
 217         of_node_put(msi->msi_dev);
 218         kfree(msi);
 219
 220         return 0;
 221 }
 222
 223 static int ppc4xx_msi_probe(struct platform_device *dev)
 224 {
 225         struct ppc4xx_msi *msi;
 226         struct resource res;
 227         int err = 0;
 228
 229         dev_dbg(&dev->dev, "PCIE-MSI: Setting up MSI support...\n");
 230
 231         msi = kzalloc(sizeof(struct ppc4xx_msi), GFP_KERNEL);
 232         if (!msi) {
 233                 dev_err(&dev->dev, "No memory for MSI structure\n");
 234                 return -ENOMEM;
 235         }
 236         dev->dev.platform_data = msi;
 237
 238         /* Get MSI ranges */
 239         err = of_address_to_resource(dev->dev.of_node, 0, &res);
 240         if (err) {
 241                 dev_err(&dev->dev, "%s resource error!\n",
 242                         dev->dev.of_node->full_name);
 243                 goto error_out;
 244         }
 245
 246         msi_irqs = of_irq_count(dev->dev.of_node);
 247         if (!msi_irqs)
 248                 return -ENODEV;
 249
 250         if (ppc4xx_setup_pcieh_hw(dev, res, msi))
 251                 goto error_out;
 252
 253         err = ppc4xx_msi_init_allocator(dev, msi);
 254         if (err) {
 255                 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
 256                 goto error_out;
 257         }
 258         ppc4xx_msi = *msi;
 259
 260         ppc_md.setup_msi_irqs = ppc4xx_setup_msi_irqs;
 261         ppc_md.teardown_msi_irqs = ppc4xx_teardown_msi_irqs;
 262         ppc_md.msi_check_device = ppc4xx_msi_check_device;
 263         return err;
 264
 265 error_out:
 266         ppc4xx_of_msi_remove(dev);
 267         return err;
 268 }
 269 static const struct of_device_id ppc4xx_msi_ids[] = {
 270         {
 271                 .compatible = "amcc,ppc4xx-msi",
 272         },
 273         {}
 274 };
 275 static struct platform_driver ppc4xx_msi_driver = {
 276         .probe = ppc4xx_msi_probe,
 277         .remove = ppc4xx_of_msi_remove,
 278         .driver = {
 279                    .name = "ppc4xx-msi",
 280                    .owner = THIS_MODULE,
 281                    .of_match_table = ppc4xx_msi_ids,
 282                    },
 283
 284 };
 285
 286 static __init int ppc4xx_msi_init(void)
 287 {
 288         return platform_driver_register(&ppc4xx_msi_driver);
 289 }
 290
 291 subsys_initcall(ppc4xx_msi_init);